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Genom ringöppningssampolymerisation av utvalda epoxider och anhydrider möjliggjordes en enkel strategi för att syntetisera funktionella sampolymerer. Sampolymererna hade förmågan att bilda tvärbundna material, och var dessutom benägna för både hydrolytisk och enzymatisk nedbrytning. Användning av organokatalysatorn PPNCl gjorde det möjligt att bilda sampolymerer genom alternerande ringöppning av epoxider och anhydrider. Utbytet var högt, och polymererna nådde molekylvikter i intervallet 0,7–7,6 kg mol-1. De omättade bindningarna i sampolymerernas sidokedjor gav dem förmågan att bilda tvärbundna nätverk. Graden av tvärbindning dikterades av sampolymerernas molekylära struktur och molekylvikt. De termiska egenskaperna hos sampolymererna reglerades genom att variera anhydriden, där strukturella skillnader mellan de valda anhydriderna hade en inverkan Tg och T5%. Tvärbindningsreaktionen resulterade i en ökning av både Tg och T5% i förhållande till de ursprungliga linjära sampolymererna. De klyvbara estergrupperna i sampolymerkedjorna gjorde det möjligt för sampolymererna att genomgå både hydrolytisk och enzymatisk nedbrytning. De nedbrutna sampolymererna påvisade en förändring i molekylvikt och dispersitet, samt en ökad viktminskning. De nedbrutna tvärbundna materialen visade på större svällning och lägre gelinnehåll än de initiala värdena före nedbrytning. Dessa resultat ger en ökad förståelse kring hur strukturen hos epoxid/anhydrid-baserade sampolyestrar påverkar deras egenskaper, så som förmågan att bilda tvärbundna material samt deras nedbrytbarhet. Förhoppningen är att denna studie ska gynna utvecklingen av nya material inom denna klass av polyestrar, och vara till hjälp för att förutse deras potentiella tillämpningar. The ring-opening copolymerization of selected epoxides and anhydrides enabled a simple strategy to synthesize functional copolymers with the ability to form crosslinked materials and prone to hydrolytic and enzymatic degradation pathways. The synthesis utilized PPNCl as an organocatalyst and allowed the formation of copolymer chains by alternating ring-opening of epoxides and anhydrides in high yield and molar mass in the range of 0.7-7.6 kg mol-1. The pendant unsaturated bonds in the copolymer chains endowed the copolymers with the ability to form crosslinking networks. The degree of crosslinking was dictated by the molecular structure and molar mass of the copolymers. The thermal properties of the copolymers were regulated by varying the anhydrides, the difference in the structure of each anhydride influence the Tg and T5%. Crosslinking reaction indeed increased the Tg and T5% from the native copolymers. The presence of ester as cleavable groups in the copolymer chains allowed the copolymers to undergo hydrolytic and enzymatic degradation. The degraded copolymers showed a change in molar mass and dispersity and increased mass loss. The degraded crosslinked materials showed higher swelling ratio and lower gel content than the initial values before degradation. These results deliver a better understanding of the structure-property relationships, the ability to form crosslinked materials, and the degradation behavior of epoxides/anhydrides-based copolyesters. They should favor the design of new materials belonging to this class of polyesters and to envisage their potential applications.

Ammonium pertechnetate reacts in mixtures of trifluoromethanesulfonic anhydride and trifluoromethanesulfonic acid under final formation of ammonium pentakis(trifluoromethanesulfonato)oxidotechnetate(V), (NH$_{4}$)$_{2}$ [TcO(OTf) $_{5}$]. The reaction proceeds only at exact concentrations and under the exclusion of air and moisture via pertechnetyl trifluoromethanesulfonate, [TcO$_{3}$(OTf)], and intermediate Tc$^{VI}$ species. $^{99}$Tc nuclear magnetic resonance (NMR) has been used to study the Tc$^{VII}$ compound and electron paramagnetic resonance (EPR), $^{99}$Tc NMR and X-ray absorption near-edge structure (XANES) experiments indicate the presence of the reduced technetium species. In moist air, (NH$_{4}$)2[TcO(OTf)5] slowly hydrolyses under formation of the tetrameric oxidotechnetate(V) (NH$_{4}$)$_{4}$ [{TcO(TcO$_{4}$)$_{4}$}$_{4}$] ���10 H$_{2}$O. Single-crystal X-ray crystallography was used to determine the solid-state structures. Additionally, UV/Vis absorption and IR spectra as well as quantum chemical calculations confirm the identity of the species.

The title compounds, C8H14O4 and C16H26O7, are precursors to dendrimers. The strong and weak hydrogen bonds in their extended structures are described., In 2,2,5-trimethyl-1,3-dioxane-5-carb­oxy­lic acid, C8H14O4, the carboxyl group occupies an equatorial position on the 1,3-dioxane ring. In the crystal, O—H⋯O hydrogen bonds form chains of mol­ecules, which are linked into a three-dimensional network by C—H⋯O hydrogen bonds. The asymmetric unit of 2,2,5-trimethyl-1,3-dioxane-5-carb­oxy­lic anhydride, C16H26O7, consists of two independent mol­ecules, which are linked by C—H⋯O hydrogen bonds. In the crystal, these units are connected into corrugated layers two mol­ecules thick and parallel to the ab plane by additional C—H⋯O hydrogen bonds.

New derivatives were synthesised by reaction of amino-containing aromatic sulphonamides with mono-, bi-, and tricyclic anhydrides. These sulphonamides were investigated as human carbonic anhydrases (hCAs, EC 4.2.1.1) I, II, IX, and XII inhibitors. hCA I was inhibited with inhibition constants (Kis) ranging from 49 to &gt, 10,000 nM. The physiologically dominant hCA II was significantly inhibited by most of the sulphonamide with the Kis ranging between 2.4 and 4515 nM. hCA IX and hCA XII were inhibited by these sulphonamides in the range of 9.7 to 7766 nM and 14 to 316 nM, respectively. The structure–activity relationships (SAR) are rationalised with the help of molecular docking studies.

Bitkiler tedavi edici özellikleri sebebiyle insan sağlığında oldukça önemli bir yere sahiptir. Bu yüzden bitki yapısını keşfetmek bitki kimyasında önemli çalışmalardan olmuştur. Bitkilerden elde edilen birçok ikincil metabolitlerin teröpatik faydalarının olduğu tespit edilmiştir. Saponinler, flavanoidler ve terpenler gibi ikincil metabolitlerin göstermiş olduğu biyolojik aktiviteler ve teröpatik faydalar, bitkilerin insan sağlığında tedavi edici özelliği olduğunu ortaya koymuştur. Bu çalışmada, triterpen içeren, saponin türevi olan gypsogenin eldesini ve elde edilen bu saf aglikon üzerinde yeni türevlendirme çalışmaları ile daha etkin bileşiklerin sentez çalışmaları gerçekleştirilmiştir. Bu sebeple gypsogenin bileşiğinin eldesi için, helva yapımında kullanımı tercih edilen, saponin, reçine ve şeker içeren Gypsophila arrostii bitki köklerinin su ekstresinden yararlanılmıştır. Halk arasında "Çöven suyu" olarak adlandırılan bu su ektresine bazik ve asidik hidroliz işlemleri uygulanarak aglikona bağlı şeker kısımlar koparılmış ce daha sonra gypsogenin bileşiğinin elde edilmesi amacıyla DCM ile ekstraksiyon yapılarak ve elde edilen DCM fazının kolon kromotografisi ile saflaştırılma işlemleri gerçekleştirilmiştir. Ardından gypsogenin aglikonun 3 numaralı karbonuna (C-3) bağlı hidroksil grubu ile farklı anhidritler arasında esterleşme tepkimesi gerçekleştirilmiştir. Elde edilen yeni semi-sentetik bileşiklerin saflaştırıldıktan sonra yapılarının aydınlatılması için erime noktası tayini ve çeşitli spektroskopik analizler (FT-IR, LC-MS, 1H NMR, APT NMR) kullanılmıştır., Plants have a very important place in human health due to their therapeutic properties. Therefore, exploring plant structure has been one of the important studies in plant chemistry. Many secondary metabolites obtained from plants have been found to have therapeutic benefits. The biological activities and therapeutic benefits of secondary metabolites such as saponin, flovanoids, and terpene have proven that plants have therapeutic properties in human health. In this study, the synthesis of more effective compounds with triterpene-containing, saponin derivative gypsogenin and new derivatization studies on this pure aglycone were carried out. For this reason, water extract of Gypsophila arrostii plant roots containing saponin, resin and sugar, which is preferred to be used in halva production, was used to obtain the gypsogenin compound. Basic and acidic hydrolysis processes were applied to this water extract, which is popularly called "Çöven juice", and sugar parts bound to aglycone were removed. Afterwards, in order to obtain pure gypsogenin compound, purification of the gypsogenin compound obtained by column chromatography of this extract extracted with DCM and water was carried out. Then, reaction of anhydride derivatives with hydroxyl group bound to carbon number 3 (C-3) of gypsogenin aglycon was carried out. Many spectroscopic analysis (CC, melting point, FT-IR, UV, 1H NMR ve APT NMR, LC-MS) applied for purification of obtaining new semi- synthetic compounds and their structures.

A combinatorial route has been applied in cure kinetics study of epoxy nanocomposites containing multi-walled carbon nanotubes (MWCNTs) based on differential scanning calorimetry and rheokinetic analyses under isothermal conditions. Pristine and amine-modified MWCNTs bearing primary and secondary amines were used at very low concentrations (0.1 and 0.3 wt.% based on epoxy weight). Model-free and model-fitting methods were applied on calorimetric data, and Kamal autocatalytic model revealed good agreement with the experimental data. In case of epoxy filled with amine-modified MWCNTs, activation energy took a value lower than that obtained for sample containing pristine MWCNTs at an identical loading because of less hindrance brought about by curing. Isothermal rheokinetic studies supported formation of a filler network during processing, which hindered epoxy-anhydride cure reaction at higher MWCNTs loadings leading to a highly crosslinked epoxy network.

La pose d’un implant est un acte invasif qui peut induire des dégâts irréversibles au niveau du tissu osseux s’il n’est pas maîtrisé. Il est du devoir du praticien de savoir adapter son protocole de forage en fonction de la qualité des tissus auxquels il est confronté afin d’être le moins traumatique possible. La biologie montre que lors du forage et de l’insertion de l’implant, l’os cortical subit plus de dégâts et concentrent tout le stress des contraintes en regard du col de l’implant. Elle nous montre également que l’os cortical cicatrise moins rapidement que l’os spongieux et subit plus de remodelage et donc de résorption. Tout ceci se traduit par une cratérisation au niveau des premières spires de l’implant. C’est pour répondre à cette problématique qu’a été créé le système Anhydride de MegaGen qui a la grande ambition de vouloir mettre fin au processus de cratérisation en minimisant au maximum les forces au niveau de l’os cortical par un ancrage exclusivement spongieux.

International audience; This is an author-deposited version published in: https://sam.ensam.euThe thermal oxidation of networks based on epoxidized linseed oil cured with an anhydride hardener was studied in the 120e200 C range by means of FTIR spectroscopy and gravimetry. Systems with 1-1 and 1e0.6 epoxy/anhydride stoichiometry were compared. The ageing tests monitored on thin films revealed that non-stoichiometric systems would be intrinsically more oxidizable than stoichiometric ones because of a higher concentration in reactive sites but stoichiometric system displays paradoxically higher levels of mass loss because those later originate from methyl cyclohexane hardener group. In the case of thick samples, the differences in oxygen diffusivity for both systems induce that oxidized layer would be slightly thicker in non-stoichiometric system than in stoichiometric ones would lead to lower in non-stoichiometric systems compared to stoichiometric ones.

Polycaprolactone-g-glycidyl methacrylate (PCL-g-GMA), a reactive interfacial agent for PCL-starch blends, is synthesized using supercritical carbon dioxide (scCO2) as reaction medium and relatively high molecular weight PCL (Mw = 50,000). Higher GMA and radical initiator intakes lead to higher functionalization degrees (FD) for PCL-g-GMA samples. A mathematical model is developed to describe the correlation between monomer and initiator intake and FD values. The model shows an excellent R2-value (0.978), which implies a good fit of the experimental data. Comparison of this model with a similar one for the reaction in the melt clearly indicates a better reaction efficiency in scCO2. Furthermore, GPC results show that less degradation occurred for samples made in scCO2. Finally, the use of the PCL-g-GMA made in scCO2 (as interfacial agent) in ternary blend of PCL/starch/PCL-g-GMA results in better mechanical properties with respect to those obtained by using the same graft-copolymer as prepared in the melt.

Further chemical investigation of two Ligularia virgaurea samples collected in China resulted in the isolation of 21 new compounds, two of which were bakkane-type sesquiterpenoids bearing an anhydride-type ring C, which was a previously unknown partial structure. These samples belonged to the V-type (the major component was virgaurenone) among the five chemotypes found in this species., Tetrahedron, 71(44), pp.8428-8435; 2015

3-Furylfulgides are photochromic compounds showing high thermal stability in their closed forms. However, their photochromic properties in the solid state should be improved further to fabricate molecular devices. Understanding how the size and the flexibility of the non-aromatic alkylidene moiety alter the crystalline state photochromic properties is also important here, as the alkylidene group is directly involved in the photochromic ring closing and opening reactions. The synthesis of four 3-furylfulgides composed of different alkylidene groups (rigid isopropyl, flexible 2-butyl, rigid cyclopentyl and flexible cyclohexyl), their crystal structures and structure–photochromic property correlation in the crystalline state are reported here. Crystallographic data along with reaction cavity volumes calculated using the programCAVITY[Ohashiet al.(1981),J. Am. Chem. Soc.103, 5805–5812] disclosed that fulgides with flexible groups at the ring closing site have more free volume around the reactive area in the crystal lattice, which can provide more space for the atomic movements in the reaction and flexibility can reduce the strain built up in the closedC-isomers by making conformations. According to UV–vis spectroscopic data, a higher yield ofC-isomers and a better fatigue resistance were obtained for the 3-furylfulgide with the largest and flexible cyclohexyl group showing greater photochromic properties in the crystalline state than the fulgide containing the smallest and rigid isopropyl group.

By use of the reversible trimerization of boronic acids, the series of boroxine cages 3-mer, 6-mer, and 12-mer were constructed from rationally designed diboronic acids whose bond angles between two C-B bonds are 60°, 84°, and 117°, respectively. Boroxine cages 6-mer and 12-mer have 1.5 and 2.5 nm sized cavities, respectively.

In order to investigate the effect of potassium addition on the composition of torrefaction condensates, two demineralized wood species were impregnated with different concentrations of K2CO3 and then torrefied at 275 °C up to an anhydrous weight loss (AWL) of 25%. Torrefaction was carried out in both a thermogravimetric analysis (TGA) instrument and a laboratory fixed-bed reactor. Condensates from the fixed bed reactor were collected and analyzed by Gas Chromatography-Mass Spectroscopy (GC–MS). TGA of raw and K2CO3-impregnated biopolymers (cellulose, xylan and lignin) were performed to facilitate interpretation of the results. TGA showed that when potassium content increased in the biomass, shorter torrefaction times were sufficient to obtain the targeted AWL. GC–MS showed, for both wood species, that potassium promotes the formation of acetol and slightly enhances acetic acid yield. The amount of some lignin derivatives (guaiacol, syringol, 4-vinylguaiacol) also rose with potassium addition. Yields of levoglucosan, LAC (1-hydroxy-(1R)-3,6-dioxabicyclo[3.2.1]octan-2-one) and DGP (1,4:3,6-dianhydro-α-d-glucopyranose), as well as furfural and 5-hydroxymethylfurfural, decreased drastically in the presence of potassium. In conclusion, small additions of potassium carbonate deeply affected thermal degradation of wood species and the speciation of torrefaction condensates. (Resume d'auteur)

Fungi residing in mangroves are considered to be a bank of novel bioactive natural products. In the screening for bioactive metabolites from mangrove-derived fungi, the ethyl acetate extract of the fermentation broth of Aspergillus fumigatus JRJ111048, a fungus isolated from the leaves of the mangrove plant Acrostichum specioum endemic to Hainan island, was found to possess insecticidal activity against Spodoptera litura. Bioactivity-guided isolation lead to the discovery of seven metabolites 1–7, including one new anhydride derivative aspergide (1), one new lipid amide 11-methyl-11-hydroxyldodecanoic acid amide (2), and five known compounds; α-ethyl glucoside (3), spiculisporic acid B (4), spiculisporic acid C (5), spiculisporic acid (6), and secospiculisporic acid B (7). Their structures were established by NMR spectroscopic and MS analyses, and by comparison of previously reported data. Insecticidal activity against S. litura and antifungal activity of these compounds were investigated. As a result, the new compound 1 showed potent insecticidal activity against newly hatched larvae of S. litura, and compound 4 displayed weak antifungal activity against Candida albicans.

The ability of styrene maleic acid copolymers to dissolve lipid membranes into nanosized lipid particles is a facile method of obtaining membrane proteins in solubilized lipid discs while conserving part of their native lipid environment. While the currently used copolymers can readily extract membrane proteins in native nanodiscs, their highly disperse composition is likely to influence the dispersity of the discs as well as the extraction efficiency. In this study, reversible addition-fragmentation chain transfer was used to control the polymer architecture and dispersity of molecular weights with a high-precision. Based on Monte Carlo simulations of the polymerizations, the monomer composition was predicted and allowed a structure function analysis of the polymer architecture, in relation to their ability to assemble into lipid nanoparticles. We show that a higher degree of control of the polymer architecture generates more homogeneous samples. We hypothesize that low dispersity copolymers, with control of polymer architecture are an ideal framework for the rational design of polymers for customized isolation and characterization of integral membrane proteins in native lipid bilayer systems.

Les hétérocycles azotés sont d’une importance considérable dans le domaine pharmaceutique. En effet, ces composés se retrouvent dans de nombreuses structures bioactives brevetées dans les dernières années. Malgré l’utilité de ces motifs, leur synthèse nécessite souvent plusieurs étapes ou encore l’utilisation de matériaux de départ fonctionnalisés. Le présent mémoire décrit de nouvelles méthodologies pour accéder à ces structures de façon douce, chimiosélective et efficace par l’activation d’amides avec l’anhydride trifluorométhanesulfonique. Dans un premier temps, une méthode en deux étapes pour accéder aux 3-aminoindazoles à partir des amides aromatiques correspondants a été développée. La séquence comprend l’activation de l’amide, suivie de l’addition d’une hydrazine protégée pour former un intermédiaire de type amino hydrazone. Cet intermédiaire peut ensuite être cyclisé dans une réaction de type amination de liens C-H en présence d’un catalyseur de palladium pour former le 3-aminoindazole désiré. Plusieurs 3-aminoindazoles ont été ainsi obtenus dans des rendements modérés à bons. Ensuite, une nouvelle méthodologie pour la synthèse des 3-amino imidazo[1,2-a]pyridines a été étudiée. Des amides contenant un motif 2-aminopyridine ont été traités avec l’anhydride trifluorométhanesulfonique afin d’obtenir l’hétérocycle désiré dans d’excellents rendements. Les produits ainsi obtenus ont pu être davantage fonctionnalisés en utilisant des réactions d’arylation de liens C-H catalysées par des composés de ruthénium et de palladium., Nitrogen-containing heterocycles are of considerable importance in the pharmaceutical area. These types of compounds are indeed found in numerous bioactive structures patented in the last few years. Although these motives are useful, their synthesis often necessitates multiple steps or the use of highly functionalized starting materials. The present thesis describes new methodologies to access these synthetically challenging structures in a mild, chemoselective and step-economic fashion by amide activation using trifluoromethanesulfonic anhydride. First, a two-step method to access 3-aminoindazoles from the corresponding aromatic amide has been developed. The sequence includes a one-pot trifluoromethanesulfonic anhydride-mediated amide activation to form the corresponding iminium trifluoromethanesulfonate, followed by the addition of a protected hydrazide to access the amino hydrazone intermediate. This intermediate can then undergo cyclization through a palladium-catalyzed C-H amination reaction to afford the desired 3-aminoindazole. Various 3-aminoindazoles could be obtained in moderate to good yields. Moreover, a new methodology for the synthesis of 3-amino imidazo[1,2-a]pyridines was developed. 2-Aminopyridine-containing amides were treated with trifluoromethanesulfonic anhydride to afford the desired heterocycles in good to excellent yields. The products thus obtained could then be further functionalized using ruthenium and palladium catalyzed C-H arylation reactions.

Aiming to determine a suitable model to describe the curing kinetics of a commercial epoxy/anhydride initiated by a quaternary amine system used for the production of glass reinforced pipes, calorimetric and infrared spectroscopic kinetics data were collected. Several phenomenological, isoconversional and mechanistics kinetics models were revisited and tried. In addition, the time-temperature-transformation diagram, which is fundamental for the design of curing cycles, was assessed from calorimetric and gel time experiments. It was found that the Kamal´s model and a mechanistic model comprising an activation reversible step followed by a propagation step (Mauri et al., 1997) were capable to well describe all the experimental data. The kinetics mechanism appeared to be independent of the initiator concentration as suggested by the constancy of the apparent activation energy obtained by the Kissinger´s method. According to the mechanistic model, the activation step resulted independent on initiator concentration while propagation rate accelerated with increasing it. The presence of glass fiber reinforcement did no affect the curing kinetics of the studied reactive system. Fil: Flores, Hugo Alejandro. Universidad Nacional de Mar del Plata. Facultad de Ingenieria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina Fil: Fasce, Laura Alejandra. Universidad Nacional de Mar del Plata. Facultad de Ingenieria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina Fil: Riccardi, Carmen Cristina. Universidad Nacional de Mar del Plata. Facultad de Ingenieria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina

Epoxy resins are inherently brittle. Thus they are toughened with reactive liquid rubbers or core–shell elastomers. Surface-modified silica nanoparticles, 20 nm in diameter and with a very narrow particle size distribution, are available as concentrates in epoxy resins in industrial quantities since 10 years. Some of the drawbacks of toughening, like lower modulus or a loss in strength can be overcompensated when using nanosilica together with these tougheners. Apparently there exists a synergy as toughness and fatigue performance are increased significantly. In this article the literature published in the last decade is studied with a focus on mechanical properties. Results are compared and the mechanisms responsible for the property improvements are discussed.

Bu çalışmada, karides kabuklarından elde edilen kitin asit klorürler, karboksilik asitler ve anhidritle etkileştirildi. Kitin ve yeni sentezlenen maddeler farklı tekniklerle karakterize edildi. Ayrıca kitin ve sentezlenen kitin türevleri ile diyot oluşturularak karakterize edildi. Kitin sırasıyla 3,5-dinitrobenzoil klorür (35DK), ftaloil diklorür (FD), o-asetilsalisiloil klorür (OAK), 4-nitrobenzoil klorür (4NK), 4,5-dikloroftalik asit (45DA), difenik asit (DA), kumarin-3-karboksilik asit (K3KA) ve benzofenon-3,3’,4,4’-tetrakarboksilik dianhidrit (B33’44’TD) maddeleri ile etkileştirildi. Kitin ve yeni sentezlenen maddeler FT-IR, katı faz CCP/MAS NMR, XRD, SEM, TGA, DSC ve iletkenlik ölçümü teknikleri ile karakterize edildi. Kitin ve yeni sentezlenen maddelerin yapılarını belirlemek için FT-IR ve C CP/MAS NMR spektroskopileri kullanılmıştır. FT-IR ve 13C CP/MAS NMR spektrumları esterleşme tepkimesinin gerçekleştiğini göstermiştir. Kitin ve sentezlenen maddelerin kristal boyutları ve kristallik indeksleri XRD analizleri ile karşılaştırıldı. XRD analiz sonuçları sentezlenen maddelerin kitine göre daha düşük kristallik derecesine sahip olduklarını göstermiştir. SEM analizi ile kitin ve sentezlenen maddelerin yüzey morfolojisi belirlendi. Termogravimetrik analiz (TGA) yöntemi ile kitin ve sentezlenen maddelerdeki kütle kaybı artan sıcaklığın bir fonksiyonu olarak belirlendi. Diferansiyel taramalı kalorimetri (DSC) tekniği ile kitin ve sentezlenen maddeler tarafından soğurulan veya salıverilen ısı miktarı sıcaklığın bir fonksiyonu olarak belirlendi. Sentezlenen maddelerin elektriksel iletkenlikleri ölçüldü ve K4NK, K35DK, K45DA, KOAK, KFD, KB33’44’TD maddelerinin yarı iletken özellik gösterdikleri tespit edildi. Ayrıca sentezlenen maddelerin diyotları (Au/polimer/n-Si) yapıldı ve bu diyotların karanlıkta ve aydınlatma altında akım-gerilim (I-V) ölçümleri alındı. Aydınlatma için 100 mW/cm2 şiddetindeki ışık kaynağı kullanıldı. I-V grafiklerinden sentezlenen maddelerin diyotlarının doğrultucu özellik gösterdiği görüldü. Daha sonra, bu diyotlara ilişkin bazı parametreler (idealite faktörü (n), engel yüksekliği (Φb) ve seri direnç (R)) hesaplandı. Son olarak, bu diyotların ışığa karşı duyarlılıkları incelendi ve bu diyotlara ilişkin bazı fotoelektrik özellikler belirlendi. Anahtar kelimeler: Kitin, polimer, sentez, karakterizasyon, asit klorür, anhidrit, schottky diyot, idealite faktörü, engel yüksekliği In this study, chitin obtained from shrimp shells was interacted with acid chlorides, carboxylic acids and anhydride. The chitin and new synthesized materials were characterized with different techniques. In addition, these diodes were characterized by forming diodes with chitin and synthesized chitin derivatives. Chitin was interacted with 3,5-dinitrobenzoyl chloride, phthaloyl dichloride, o-asetylsalicyloyl chloride, 4-nitrobenzoyl chloride, 4,5-dichlorophthalic acid, diphenic acid, coumarin-3-carboxylic acid and benzophenone-3,3’,4,4’-tetracarboxylic dianhydride, respectively. The chitin and the synthesized materials were characterized by FT-IR, solid state 12 C CP/MAS NMR, XRD, SEM, TGA, DSC and conductivity measurement techniques. FT-IR and 13 C CP/MAS NMR spectroscopies were used to determine the structure of chitin and synthesized materials. FT-IR and 13C CP/MAS NMR spectra showed that esterification reaction is realized. Crystal size and crystalline index of the chitin and synthesized materials were compared by XRD analysis. XRD analysis results showed that synthesized materials have lower crystallinity degree according to chitin. Surface morphology of chitin and synthesized materials was determined by SEM analysis. Mass loss in chitin and synthesized materials with thermogravimetric analysis (TGA) method was determined as a function of increasing temperature. The amount of heat absorbed or released by chitin and synthesized materials with differential scanning calorimetry (DSC) technique was determined as a function of temperature. The electrical conductivity of the synthesized materials was measured and it was found that K4NK, K35DK, K45DA, KOAK, KFD, KB33’44’TD are semiconductor. Besides, the diodes of synthesized materials (Au/polymer/n-Si) were constructed, and the current-voltage (I-V) measurements of these diodes in dark and under illumination were taken. It has been used a light source of 100 mW/cm intensity for lighting. It was seen from I-V graphics that the diodes of synthesized materials show rectifier property. Later on, some parameters (ideality factor (n), barier height (Φb) and series resistance (R)) related to these diodes were calculated. Lostly, the susceptibility of these diodes to light was investigated, and some photoelectric properties related to these diodes were determined. s Keywords: Chitin, polymer, synthesis, characterization, acid chloride, anhydride, schottky diode, ideality factor, barrier height Bu çalışma Dicle Üniversitesi Bilimsel Araştırma Projeleri Koordinatörlüğü tarafından ZGEF.15.012 Proje numarasıyla desteklenmiştir.

Bagasse acetate butyrates were prepared homogeneously in 1-butyl-3-methylimidazolium chloride ([C4mim]Cl) ionic liquid from ball-milled sugarcane bagasse by acylation with acetic anhydride and butyric anhydride. The parameters, including reaction temperature, reaction time, feeding method of adding anhydrides, the dosage of total anhydrides to SCB, and the molar ratio of acetic anhydride to butyric anhydride, were considered, and the extent of acylation was measured by weight percent gain (WPG). The results showed the positive effects of reaction duration and total anhydride dosage on WPG and the negative effects of reaction temperature and molar ratio of AA/BA on WPG. The feeding method of acetylation after butyrylation resulted in the increased WPG compared with acetylation before butyrylation. FT-IR and 1H–13C correlation 2D NMR (HSQC) studies provided evidence for acylation. The bagasse acetate butyrates showed increased thermal stability after acylation. This study provides a new way for high value-added utilization of renewable lignocellulosic biomass.

International audience; The global reaction between acetic anhydride and a fatty acid yields, at equilibrium, an asymmetric acetic-aliphatic anhydride in a medium containing finally: acetic-fatty anhydride, acetic anhydride, fatty acid, acetic acid and fatty anhydride. No solvent or catalyst was used to evaluate the impact of the actual reactivity of the anhydrides. The competition between the formation of acetyl and fatty acyl ester functions was evaluated by determining the ratio of acetyl/fatty acyl groups grafted on solid cellulose. The influence of temperature, reaction time, and length of fatty chain on the total degree of substitution and on the ratio of acetyl/fatty acyl ester functions was investigated. For the first time, a correlation has been established between esterification and the length of the aliphatic chain of the fatty acid. Reactivity of the medium decreased with the number of carbons in the fatty acid, raised to the power 2.37.

An efficient protocol has been demonstrated for the synthesis of pthalimides, maleimides and succinimides in excellent yield using trifluoroacetic acid as the reaction medium and promoter.

Impaction bone grafting in revision arthroplasty is a common and successful procedure to restore primary bone stock. Reducing the amount of bone needed to fill large grafts has been a driving force for the use of synthetic materials that can act as extenders or substitutes. To this end, we evaluated the mechanical properties of a new class of biodegradable polymer beads with and without donor bone to determine its suitability for use in impaction grafting. Biodegradable methacrylated anhydride beads were synthesized using thermal polymerization techniques. The mechanical properties of the beads were then tested in an impaction grafting test chamber and compared with morsellised porcine allograft. The beads, porcine allograft and a 50/50 combination all had similar mechanical properties, both in compression and relaxation. Pure polymer beads compacted significantly less than pure allograft and retained macroporosity after impaction. Our results suggest that the biodegradable beads have sufficient mechanical properties to be considered as an impaction grafting substitute or extender. Their ability to fill space whilst retaining macroporosity may be advantageous for tissue ingrowth and remodeling. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.

This work is funded by the EPSRC UK Reaction of Woollins' reagent ― WR , 2,4-bis(phenyl)-1,3-diselenadiphosphetane 2,4-diselenide [{PhP(Se)(μ-Se)}2] ― with aromatic diols in refluxing toluene afforded a series of novel five- to ten-membered phosphorus-selenium heterocycles 1 – 10 with an O–P(Se)–O or O–P(Se)–Se–P(Se)–O or O–P(Se)–O–P(Se)–O linkage in 12–74 % isolated yields. It was found that the diphosphorus species O–P(Se)–Se–P(Se)–O rings could be readily reduced into the monophosphorus species O–P(Se)–O rings in almost quantitative yields via further reaction with another equivalent of corresponding aromatic diol. All new compounds have been characterized by IR, 1H NMR, 13C NMR, 31P NMR, 77Se NMR, mass spectrometry and elemental analysis or accurate mass measurement. Seven representative X-ray structures are reported. Postprint

Photo-crosslinkable, fumaric acid monoethyl ester-functionalized poly(trimethylene carbonate) oligomers were synthesized and copolymerized with N-vinyl pyrrolidone (NVP) and vinyl acetate (VAc) to form biodegradable polymer networks. The copolymerization reactions were much faster than homopolymerization of the fumarate end-groups of the macromers. The hydrophilicity of the networks could by varied by mixing NW and VAc at different ratios. The prepared network extracts were compatible with NIH 3T3 fibroblasts. Release of vitamin B12, used as a model drug, could be tuned by varying network hydrophilicity and macromer molecular weight. A more hydrophilic and less densely crosslinked network resulted in faster release. (C) 2010 Elsevier B.V. All rights reserved.

The synthesis of two reactive interfacial agents for starch-polycaprolactone (PCL) blends, PCL-g-glycidyl methacrylate (PCL-g-GMA) and PCL-g-diethyl maleate (PCL-g-DEM) is described. The compounds were prepared by reacting a low molecular weight PCL. (M(w) 3000) with GMA or DEM in the presence of benzoylperoxide (BPO) at 130 degrees C. The effect of important process variables (initiator and monomer intakes) on the functionalization degree (FD) of the GMA and DEM units to the PCL backbone was explored in detail and quantified using multivariable linear regression. The highest FD values (up to 45%) were observed for PCL-g-GMA, at relatively high GMA and BPO intakes. The FD values for PCL-g-DEM were considerably lower (up to 7%). The reactive interfacial agents were tested for their performance in starch-PCL blends. The mechanical properties of the compatibilized blends differ from the uncompatibilized ones and in particular the elastic modulus for the compatibilized blends is significantly higher. At relatively low starch intakes, PCL-g-DEM has at least a comparable performance than PCL-g-GMA. These observations may be explained tentatively on the basis of the distribution of the functional groups (GMA or DEM) along the PCL back-bone. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 114: 23152326,2009

It has been widely recognised that high energy radiation can be effectively applied to the cure of epoxy resins in applications as composite matrices or structural adhesives with improvements in product quality and/or reduction in production costs. In the presence of suitable initiators, polymerisation of epoxies occurs via cationic mechanism, thus restricting the choice of the resin system components to species which do not contain electron donor groups. The present investigation is aimed to identify suitable co-monomers to be formulated with an epoxy resin, resulting in different cure reaction kinetics and application properties of the cured resin. In particular, four different anhydride types, three dicarboxylic and one tetracarboxylic, have been formulated at the same weight ratio with a diglydilether of bisphenol F and a photo-initiator. Resin samples, irradiated at different integrated doses, have been characterised with solubility tests, dynamic-mechanical thermal analysis and three point flexural tests, showing a response which is strongly affected by the specific chemical structure of the anhydride co-monomer. Post-irradiation thermal treatments carried out on samples irradiated at the lower dose suggest different reaction patterns, with different controlling factors depending on the activation mechanism (temperature or γ -rays).

At the molecular level, the functions of helical patterns are often directly associated with the stability of thesearchitectures, (in α-helices). For example, upon removal of such an entity from the protein’s tertiary structure,the peptidic helix becomes flexible and thus inactive. In order to control the rigidity of these architectures,several strategies have been used and the construction of completely artificial well folded molecules known asfoldamers is one them. Our group mainly focuses on helical aromatic oligoamide foldamers and to dateseveral studies have been carried out to investigate factors affecting the helical stability; the influence ofoligomer length, solvent effects and the effect of aliphatic linkers within a helical aromatic sequence.In the present study we investigate the helical propensity of five commonly used aromatic monomers infoldamer synthesis and by using NMR spectroscopy, X-ray crystallography and dynamic chiral HPLC weevaluate their contribution in helical stability. Additionally, inspired by the role of disulfide bonds in proteins wedecided to explore their effect on helical stability. For this reason intra- and inter-molecularly disulfide bondedcompounds were designed and synthesized. Their stability was studied using NMR spectroscopy, chiral HPLCand CD experiments.Finally, the synthesis of mono-disperse helical strings of polymeric dimensions through a convergent, segmenttripling strategy has been developed. This protection/deprotection free synthesis was carried out byconnecting oligomeric blocks via a labile anhydride functionality., Au niveau moléculaire, les fonctions des motifs hélicoïdaux sont souvent associées à la stabilité de cesarchitectures. Par exemple, lorsqu’une hélice α est isolée de la structure tertiaire des protéines, celle-cidevient alors flexible et perd son activité. Afin de contrôler la rigidité de ces architectures, différentesapproches ont été proposées dont la construction d’édifices moléculaires repliés de façon contrôlée : lesfoldamères. Notre équipe s’intéresse aux foldamères d’oligoamide aromatique hélicoïdaux et à l’heureactuelle plusieurs études ont déjà été menées afin de comprendre les facteurs influant la stabilité de telleshélices: la longueur de l’oligomère, le solvant et l’effet de l’introduction d’un espaceur aliphatique dans laséquence. Lors de ce travail nous nous sommes tout d’abord intéressés à la capacité de repliement de cinqmonomères aromatiques couramment utilisés pour la préparation de foldamères. Leur contribution dans lastabilité hélicoïdale du système a été évaluée par RMN, diffraction des rayons-X et HPLC chirale dynamique.Inspirés par le rôle des ponts disulfure dans les protéines, nous avons décidé d’explorer l’effet d’une telleliaison sur la stabilité des hélices d’oligoamide aromatique. Deux composés contenant une liaison disulfureintramoléculaire ou deux liaisons intermoléculaires ont été synthétisés et leur stabilité étudiée par RMN, HPLCChiral et Dichroïsme circulaire.Enfin, la synthèse d’hélices moléculaires de grandes dimensions (assimilables à celles de polymèresmonodisperses) a été réalisée par une approche convergente de triplement de longueur de segment via laformation de liaisons anhydrides entre blocs oligomériques.

We investigated the synthesis of maleic anhydride by oxidehydration of a bio-alcohol, 1-butanol, as a possible alternative to the classical process of n-butane oxidation. A vanadyl pyrophosphate catalyst was used to explore the one-pot reaction, which involved two sequential steps: 1) 1-butanol dehydration to 1-butene, catalysed by acid sites, and 2) the oxidation of butenes to maleic anhydride, catalysed by redox sites. A non-negligible amount of phthalic anhydride was also formed. The effect of different experimental parameters was investigated with chemically sourced 1-butanol, and the results were then confirmed by using genuinely bio-sourced 1-butanol. In the case of bio-1-butanol, however, the purity of the product remarkably affected the yield of maleic anhydride. It was found that the reaction mechanism includes the oxidation of butenes to crotonaldehyde and the oxidation of the latter to either furan or maleic acid, both of which are transformed to produce maleic anhydride.

New dendritic modifiers have been synthesized by amidation of hyperbranched poly(ethylenimine)(PEIs) with 10-undecenoic acid to obtain hyperbranched polymers (HBPs) with different degree of modification. These HBPs have been used as toughness modifiers in a proportion of 10 and 20% in reference to the epoxy resin in diglycidyl ether of bisphenol A (DGEBA)/methyltetrahydrophthalic anhydride (MTHPA) formulations. The curing process has been studied by dynamic scanning calorimetry and by rheometry, which allow the kinetic constants and the gel and vitrification times to be evaluated. The materials obtained have been thermally characterized and their mechanical properties have been evaluated. An increase in impact resistance has been achieved and the T-g of all thermosets prepared was higher than 100 degrees C in spite of the flexible structure of the PEI modifiers. (C) 2015 Elsevier B.V. All rights reserved.

Jeannine H. Powell, Edward M. Johnson II and Peter M. Gannett*Department of Basic Pharmaceutical Sciences, West Virginia University School of Pharmacy,P. O. Box 9530, Morgantown, West Virginia, USA. Tel. (304)-293-1480, Fax (304) 293-2576.*Author to whom correspondence should be addressed; e-mail pgannett@hsc.wvu.eduReceived: 8 May 2000; in revised form 13 November 2000 / Accepted: 14 November 2000 /Published: 18 December 2000Abstract: Methods to reduce the carboxylic acid moiety in 3-carboxy-2,2,5,5-tetramethyl-pyrrolin-1-oxyl to an alcohol as an intermediate toward the corresponding aldehyde havebeen explored and an improved method has been developed.Keywords: Nitroxide, spin label, reduction, carboxylic acid, alcohol, anhydrideIntroductionSpin-labeled nucleic acids have been proposed as probes for the study of DNA conformation anddynamics [1,2]. A potentially very useful moiety is a thymidine analog coupled via an acetylene bridgeto a pyrrolin-N-oxyl molecule [2]. The synthesis of this spin-labeled nucleic acid begins with stablenitroxides described by Rozantsev [3]; further elaboration of these compounds is described in severalsources [2,4]. In our hands, one of the most problematic steps in the overall synthesis is the reductionof the carboxylic acid moiety in 1 to the alcohol 2, which is then oxidized to the aldehyde 3, withoutperturbation of the nitroxide (Figure 1).Here we report several methods we have utilized for theconversion of 1 into 2 and in one instance of 1 into 3.

International audience; The reactions between polycarbonate (PC) and polystyrene-block-poly(ethylene-butylene)-block-polystyrene-grafted-maleic anhydride (SEBS–g–MAH) is a novel, convenient, solvent-free, and easy way to create SEBS–g–PC in order to compatibilize polystyrene and PC blends. This study determines the most efficient catalyst among Tin (II) bis(2-ethylhexanoate) (SnOct2), 1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD), Titanium tetrabutoxide (Ti(OBu)4) and Sodium 4-hydroxybenzenesulfonate dihydrate (SHBS) in the molten state at 220 °C. From 20 to 30 wt% of SEBS-g-MAH (or KFG) chains became insoluble. The size exclusion chromatography analyses showed the formation of a double distribution due to PC chains scission and grafting reactions onto SEBS–g–MAH with the exception of the Ti(BuO)4 use. Fine microstructures with a percolation effect proved the efficiency of both the TBD and the SnOct2. The PC transition temperature decreased in at least 10 °C, confirmed that only SnOct2 and TBD were efficient to catalyze the grafting reactions. No evolution was observed with the SHBS and Ti(OBu)4.

Kao derivat neurotransmitora prisutnog u živčanim sustavima sisavaca, GABOB (γ-amino-β-hidroksibutanska kiselina) se koristi u liječenju epilepsije, shizofrenije i drugih sličnih kliničkih poremećaja. Dodatnu važnost ima kao intermedijer u sintezama spojeva poput karnitina (vitamin Bt), negamicina (antibiotik) ili mikrosklerodermina E, antitumorskog cikličkog peptida. Polazeći od dietil-3-hidroksiglutarata, uvedeno je nekoliko različitih zaštita hidroksilne skupine. Hidrolizom estera i dehidratacijom odgovarajuće dikiseline pripravljeni su ciklički mezo anhidridi. Enantioselektivnom alkoholizom anhidrida u prisutnosti katalizatora na bazi alkaloida dobiveni su kiralni monoesteri u optičkim čistoćama > 90 %. Na slobodnom karboksilnom kraju je potom Curtiusovom pregradnjom uvedena zaštićena amino skupina. Na taj način je dobiven kiralni gradivni blok s tri različite zaštitne skupine.

We provide a comprehensive account of the 1,3-dipolar cycloaddition reactions of azomethine ylides with carbonyl dipolarophiles. Many different azomethine ylides have been studied, including stabilized and non-stabilized ylides. Of the carbonyl dipolarophiles, aldehydes including formaldehyde are the most studied, although there are now examples of cycloadditions with ketones, ketenes and carboxyl systems, in particular isatoic anhydrides and phthalic anhydrides. Intramolecular cycloadditions with esters can also occur under certain circumstances. The oxazolidine cycloadducts undergo a range of reactions triggered by the ring-opening of the oxazolidine ring system.

Coumarin-based dye (Z)-N-(7-cyano-9,9,15,15-tetramethyl-9,10,11,13,14,15-hexahydro-6H-benzo[4'',5'']imidazo[1'',2'':1',2']pyrido[3',4':5,6]pyrano[2,3-f]pyrido[3,2,1-ij]quinolin-6-ylidene)pent-4-ynamide (3) was obtained in 81% yield by reaction between primary imine precursor 1 and pent-4-ynoic anhydride (2) under thermal conditions. The title compound was characterized by elemental analysis, melting point, 1H-NMR, 13C-NMR, FT-IR, mass, UV-vis and fluorescence spectroscopy.

5 páginas, 1 figura, 1 esquema.-- This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license., Coumarin-based dye (Z)-N-(7-cyano-9,9,15,15-tetramethyl-9,10,11,13,14,15-hexahydro-6H-benzo[4'',5'']imidazo[1'',2'':1',2']pyrido[3',4':5,6]pyrano[2,3-f]pyrido[3,2,1-ij]quinolin-6-ylidene)pent-4-ynamide (3) was obtained in 81% yield by reaction between primary imine precursor 1 and pent-4-ynoic anhydride (2) under thermal conditions. The title compound was characterized by elemental analysis, melting point, 1H-NMR, 13C-NMR, FT-IR, mass, UV-vis and fluorescence spectroscopy., The authors thank Ministerio de Ciencia e Innovación−FEDER (CTQ2010−17436; J.B. predoctoral fellowship), Gobierno de Aragón (research group E40), CSIC (project PIE 200980I059) and University of Regensburg (Anschubfinanzierung von Wissenschaftlichen Projekten-2011) for financial support.

The synthesis and characterization of two new aromatic–aliphatic hyperbranched polyesters modified with long and short vinylic chains was reported. These hyperbranched polymers were used as toughening modifiers of epoxy/anhydride thermosets. The curing of mixtures of diglycidyl ether of bisphenol A and hexahydro-4-methylphtalic anhydride with different proportions of both hyperbranched polymers using N,N-benzyldimethylamine as catalyst was investigated by differential scanning calorimetry. The kinetic of curing process was established using an isoconversional integral procedure. The characterization of these materials was done by means of several thermal analysis techniques and their morphology was investigated by electron microscopy. The addition of highly branched structures led to homogeneous morphologies and a more toughening fracture of the thermosets in comparison to the neat epoxy/anhydride material. The modified thermosets presented slightly lower glass transition temperature than the unmodified one and the thermal stability barely changed by the addition of the modifiers.

Bu araştırmada, kimyasal modifikasyon ile değişik molekül ağırlıklarındaki (3,5.105 ve 5,0.105) saf polistirenler (PS), süksinik anhidrit (SA), maleik anhidrit (MA) ve ftalik anhidrit (FA) gibi organik anhidritlerle modifiye edilmiştir. Polistiren kompozitler (KPS) ve epoksi reçinesinin (DGEBA), allilgilisiteter (AGE) ve 2,3-epoksipropilmetakrilat (EPM) ile karışımından oluşan epoksi kompozitleri hazırlanmıştır. Elde edilen bütün malzemelerin yoğunlukları ve ultrasonik darbe-yankı metodu ile ultrasonik hızları ölçülmüştür. Ultrasonik dalga hızlarının ölçülmesinde 35 MHz' lik bilgisayar kontrollü çözümleyici, 60 MHz' lik dijital osiloskop kullanılmıştır. Ultrasonik hız ölçümleri darbe-yankı metodu ile 2,25; 3,5 ve 5 MHz frekanslarında oda sıcaklığında yapılmıştır. Elde edilen yoğunluk ve hız değerlerinden bütün numunelerin esneklik modülleri (L, G, K, E), Poisson oranları (?) ve akustik empedans (Z) değerleri hesaplanmıştır. Böylece kimyasal modifikasyon metodu ile polistirenin aromatik halkasına çeşitli fonksiyonel grupların bağlanmasının ve DGEBA' nın AGE ve EPM modifikatörleri ile modifiye edilmesinin sırasıyla PS ve DGEBA' nın mekanik özelliklerine olan etkisi ultrasonik yöntemle araştırılmıştır. Araştırmada elde edilen verilerden saf polistirenlerin SA, MA ve FA ile modifikasyonunun boyuna ve enine ses dalga hızlarını ve esneklik modülü değerlerini arttırdığı tespit edilmiştir. Ayrıca saf PS ve KPS' lerin çekme testi ve ultrasonik darbe-yankı tekniği ile ölçülen Young modülü değerlerinin birbirine çok yakın olduğu tespit edilmiştir., In this study, the pure polystyrenes (PS) with different molecular weights (3,5.105 and 5,0.105) were modified by the chemical modification with succinic anhydride (SA), maleic anhydride (MA) and phthalic anhydride (PhA). The composites of polystyrene (CPS) and composites of epoxy resin (CDGEBA) that have been formed by mixing epoxy resin with allylglycidylether (AGE) and 2,3-epoxypropyl methacrylate (EPM), were prepared. A computer controlled analyzer with 35 MHz and a digital oscilloscope with 60 MHz were used for measuring the velocities of ultrasonic wave. The measurement of ultrasonic velocity carried out by pulse echo method at frequencies of 2,25; 3,5 and 5 MHz at room temperature. The values of acoustic impedance (Z), Poisson ratio (µ) and coefficients of elasticity (L, G, K, E) of materials were calculated by values of densities and velocities that obtained. Thus, the effect of binding various multifunctional groups to the polystyrene?s aromatic ring through chemical modification and respectively, modificating the DGEBA by AGE and EPM on mechanical characteristics of the PS and DGEBA were investigated using the ultrasonic method. By the results obtained from the investigation it have been established that the longitudinal and shear sound wave velocities and the values of all the elasticity constants of pure polystyrene were increased by modification of polystyrene with SA, MA and PA. Furthermore, it have been established that the values of Young modulus measured by the tensile test and ultrasonic method were closed to each other very much.

Družba Kema Puconci, d.o.o. je izvozno naravnano podjetje, ki ima tehnološko najsodobnejšo organizirano proizvodnjo kremenovih peskov in materialov za zaključna dela v gradbeništvu. Z inovativno politiko, nenehnimi vlaganji ter odgovornim občutkom za prave priložnosti so se uspeli dvigniti iz povprečja naše panoge. Tako so danes prepoznavna družba v slovenskem in širšem gospodarskem prostoru s pozitivnimi trendi stalne rasti. Proizvodni program, ki zajema pester nabor izdelkov za celovite rešitve v gradbeništvu, nenehno dopolnjujejo in nadgrajujejo z novimi in inovativnimi izdelki. V okviru tega je podjetje dalo pobudo za razvoj nove podlivne malte, ki bi bila uporabna za podlivanje jeklenih konstrukcij, temeljnih plošč strojev in temeljev ter za zalivanje sider in stikov. V diplomskem delu predstavljamo potek in rezultate raziskav na to tematiko. Izvedli smo več sklopov meritev. Merili smo linearne deformacije vzorcev z metodo po Graaf Kaufmannu. Za to metodo smo izdelali po štiri prizmice za vsak vzorec. Dve smo negovali na zraku, dve v vodi. Poleg tega smo merili še razlez, tlačne in upogibne trdnosti, prostorninsko maso sveže malte, čas vezanja. Določali smo tudi zrak v sveži malti. Razmerje cement — pesek smo določali s pomočjo sejalnih analiz. Za osnovo smo izbrali produkt s trga, ki ga proizvaja eno izmed konkurenčnih podjetij. Raziskave smo najprej opravili na tem produktu in ga poimenovali Podlivna malta — izdelek s trga. Nadaljnje raziskave smo opravili iz dveh vidikov formulacije kalcijevega sulfoaluminata (CSA) in sicer enkrat smo CSA formulirali sami z dodatkom anhidrita in aluminatnega cementa, drugič smo ga dodali v obliki gotovega proizvoda s trga. Pri formulaciji CSA-ja z dodatkom alumatnega cementa in anhidrita smo izdelali pet skupin vzorcev. Vzorce smo poimenovali z oznakami A1, A1-C, A2, A3 in A4. Pri formulaciji CSA-ja z dodatkom proizvoda s trga smo uporabljali dodatek Denka CSA#20. Izdelali smo štiri skupine vzorcev in jih poimenovali D1, D2, D5 in D6. Poleg dodatka Denka CSA#20 smo uporabili še dodatek Denka SC-1 (pospešilo) in Denka D200 (zaviralo). Ugotovili smo, da vzorec A3 in vzorec D1 dosegata najboljše rezultate glede linearnih deformacij in trdnosti, vendar dajeta nekoliko slabše rezultate glede časa vezanja. Vzorec A3 pa ima poleg tega še slab razlez. Predlagamo, da se raziskave nadaljujejo v smeri izboljšanja časa vezanja, pri vzorcu A3 pa še v smeri izboljšanja razleza. Po opravljenih laboratorijskih preiskavah je potrebno izračunati lastni ceni obeh izdelkov, na osnovi katerih se bo podjetje lahko odločilo za proizvodnjo katerega izmed njiju. Omejitve diplomskega dela so bila cenovna razmerja, saj je bilo potrebno zagotoviti maksimalno učinkovitost nove formulacije za doseganje ciljnih lastnosti proizvoda ob čim manjšem možnem povečanju lastne cene proizvoda. Te lastnosti so bile povečanje tlačne trdnosti nad 60 MPa, doseganje volumske ekspanzije sveže malte do +0,4 % in eliminacija linearne deformacije (krčenja) v plastičnem stanju. Kema Puconci d.o.o. is an export oriented company that integrates the most modern technological organization in production of quartz sands and materials for final works in construction. With innovative politics, constant investments and a responsible feeling for right choices it succeeds to get out of the average of its branch. So it's a recognized company today in Slovenia and also at a wider economic space with positive trends of permanent growth. The production programme, which includes a diverse palette of products for entire solutions in construction, is constantly supplemented and overbuild with new and innovative products. Under these activities the company initiated a development project of a new type of underpouring compound that is intended for grouting underneath the steel structures, the base plates of machines, for anchoring and joint casting. This diploma work represents the course and results of the research project. Different sets of testing procedures have been implemented. The linear deformation was determined through the Graaf-Kaufmann method. Four specimens of each tested type of product have been prepared for implementation of the Graaf Kaufmann method. Two specimens were conditioned by the standard climatic conditions, while other two specimens were conditioned in water. Besides that, the flowing capabilities, compression and flexural strength, density and setting time were determined. The fresh mortar air content was also determined. The cement-sand ratio was determined based on the sieving analysis. The starting point of our researches was a product that is manufactured by one of the competitors. Initial researches have been done on the competitive product, which was then titled as a »Underpouring compound – the product from market«. Further researches were implemented from calcium-sulphoaluminate (CSA) formulation point of view. In first case the CSA was formulated based on addition of the anhydrite and aluminate cement. In second case the CSA was added as prefabricated product which is available in the market. For the formulation of CSA that was based on the aluminate cement and anhydrite addition five groups of specimens were prepared. The specimens were designated as A1, A1-C, A2, A3 and A4. For the formulation of CSA that was based on the prefabricated product the DENKA CSA#20 additive was used. The DENKA SC-1 (accelerator additive) and DENKA D200 (retarder additive) were both applied in addition to the DENKA CSA#20. It was find out that the A3 and D1 specimens achieved best results regarding linear deformation and strength properties, but the results of the setting time determination were slightly poor. Besides that, the A3 specimen developed poor flowing performance. I am suggesting that research on the setting time improvement shall be continued as well as further research regarding flowing properties improvement in case of the A3 specimen. After the laboratory research completion the cost prices of both formulations shall be calculated, so the company's decision will be done upon which product to manufacturing in the future. The limitations of this diploma work were primarily the cost price ratios, for it was necessary to provide the most efficient formulation that achieves the objectives of the project by less possible increasing of the product's cost price. These objectives were increasing of the product's compressive strength over 60 MPa, achieving the volume expansion of the fresh mortar up to +0,4 % and elimination of the linear deformations (shrinkage) in its plastic phase.

Activation of mannuronic acid esters leads to a conformational mixture of alpha-anomeric triflates, in which the equatorial triflate ((1)C(4), chair) is formed preferentially. This unexpected intermediate clearly opposes the anomeric effect and is mainly stabilized by the electron-withdrawing carboxylate function at C-5. Because the anomeric center carries a significant positive charge, the (1)C(4), mannopyral chair approximates the favored (3)H(4), half-chair oxacarbenium ion conformation. The excellent B-selectivity in glycosytations of mannuronates is postulated to originate from the cooperative action of the triflate counterion and the (stereo)etectronic effects governing oxacarbenium ion stabilization in the transition state leading to the 1,2-cis product.

Polyamide 6 (PA6) was treated in the melt at 230 degrees C in a discontinuous mixer with diethyl maleate (DEM) and dicumyl peroxide (DCP). The grafting of DEM to PA6 chains was investigated by H-1 NMR analysis, and it reached easily up to 4.5 mol %. The grafted diethyl succinate groups (DES) can successively react with terminal ammo groups of different polyamide macromolecules, thus yielding branched polyamide macromolecules. The average degree of branching, determined by titration analysis, is about one per macromolecule under the used experimental conditions and can be improved by further blending with PA6. Thermal analysis of branched PA6 showed lower melting and crystallization temperatures than those of simply processed linear PA6. Blends of unmodified and functionalized polyamide showed a higher viscosity and a more effective shear thinning behavior than the simply processed linear PA6. Experimental evidence was discussed, and a possible reaction mechanism was proposed.

This PhD thesis describes the desymmetrization of easily accessible meso-anhydrides by cinchona alkaloid-mediated opening with benzyl alcohol. This procedure was found to be applicable to a variety of structurally different substrates and leads to the corresponding optically active hemiesters with enantioselectivities of up to 99%. A simple reaction protocol was developed which allows the synthesis of either enantiomer selectively, generally without need of additional purification of the resulting benzyl monoester by chromatography or recrystallization. The synthetic usefulness of the method was demonstrated by the preparation of optically active beta-amino acids through a reaction sequence involving a Curtius degradation as a key step. Their complete deprotection could be accomplished in a single step by simple hydrogenation enabling the isolation of rather sensitive products. As an extension of this work, a general strategy for the synthesis of optically active C2- and C1-symmetric bisoxazolines was developed. Accordingly, eight cyclopentane derivatives were prepared in good overall yields. The catalytic activity of the copper (II) and zinc (II) complexes derived from these eight ligands was tested in the asymmetric Diels-Alder reaction. In addition, the effect of temperature and counterion on the reaction selectivity was also investigated. The catalytic behavior of the copper (II) complexes has also been evaluated in the related hetero Diels-Alder reaction between 1,3-cyclohexadiene and ethyl glyoxalate. The HDA-adducts were always obtained with high diastereoselectivities and promising enantioselectivities. Enantioselective cyclopropanation of styrene was the reaction chosen to determine the efficiency of the [Cu(box)]-(OTf) systems. In this context, enantioselectivities of up to 83 and 87% ee were attained for the trans and cis cyclopropanated products, respectively.

Tetrahydrophthalic (THA) and maleic (MA) anhydrides were grafted onto linear low density polyethylene with comonomer 1-butene and 1-octene (LLDPE) in solution in the presence of benzoyl peroxide (BPO) following experimental designs, where anhydride and BPO concentrations, type of comonomer and reaction time were varied. The formulations were analyzed by Fourier transform infrared spectroscopy (FTIR). In the case of THA modified polyolefins, the time of reaction and the interaction between time of reaction and THA concentration influenced the process, whereas the MA and BPO concentrations influenced the grafting of MA onto polyolefins. THA and MA modified polyolefin samples with similar grafting contents were analized by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). THA and MA functionalized polyolefins presented reduction in the melting temperature of 4.3 °C and 1.4 °C, respectively, comparing with the original polymer. These effects corroborate with the strong reduction in the areas of the diffraction peaks (110) and (200) after the grafting process. Polietileno de baixa densidade (LLDPE) com comonômeros 1-buteno e 1-octeno foram funcionalizados com anidrido tetrahidroftálico (THA) e anidrido maléico (MA) em solução na presença de peróxido de benzoíla (BPO), de acordo com planejamentos fatoriais. As variáveis testadas foram concentração de anidrido, concentração de peróxido, tempo de reação e tipo de comonômero. As formulações foram analisadas por espectroscopia vibracional no infravermelho FTIR. Na funcionalização com THA o efeito principal tempo de reação foi significativo, assim como, a interação deste com a concentração de THA, enquanto que no caso do MA as concentrações de BPO e MA foram significativas. Poliolefinas modificadas com teores semelhantes de THA e MA foram analisadas por calorimetria exploratória diferencial (DSC) e por difração de raios X (XRD). Amostras modificadas com THA e MA apresentaram redução na temperatura de fusão de 4,3 °C e 1,4 °C, respectivamente, com relação ao polímero original. Alterações devido à funcionalização também foram evidenciadas por forte redução nas áreas dos picos de difração relativos aos planos cristalinos (110) e (200), corroborando com os dados de calorimetria exploratória diferencial (DSC).

“Maghnite” a montmorillonite sheet silicate clay, exchanged with protons to produce “H-Maghnite” is an efficient catalyst for polymerization of many vinylic and heterocyclic monomers (Belbachir, M. U.S. Patent. 066969.0101 –2001). The structure compositions of both “Maghnite” and “H-Maghnite” have been developed. This catalyst was used for the polycondensation of the tetrahydrofuran with phthalic anhydride. The polymerization was performed under suitable conditions at temperature (40°C), in presence of acetic anhydride. Experiments revealed that polymerization induced by “H-Maghnite”, proceed in bulk and the conversion increases with increasing “H-Maghnite” proportion. Keywords: Anhydride, Maghnite, Montmorillonite, Phthalic, Tetrahydrofuran. Introduction The use of acid treated clays as a solid source of protons in a number of industrial significant reactions continue because they constitute a widely available, inexpensive solid source of protons, e.g. they were employed as cracking catalysts until the 1960s [1] and are still currently used in industrial processes such as the alkylation of phenols [2] and the dimerization and polymerization of unsaturated hydrocarbons [3]. Montmorillonites have both Bronsted and Lewis acid sites and when exchanged with cations having a high charges density, as protons, produce highly-active catalysts for acid-catalysed reactions [4]. Intercalated organic molecules are mobile and can be highly polarized when situated in the space

The uncatalyzed cure of a commercial tetrafunctional epoxy monomer TGDDM (N,N,N′,N′-tetraglycidyl-4,4′-diaminodiphenylmethane) with hexahydrophthalic anhydride (HHPA), using variable stoichiometric ratios is reported. The reaction was followed by differential scanning calorimetry (DSC). Two kinds of experiments were performed: (1) fresh samples were run at several heating rates, and (2) samples, precured a certain time in an oil bath at constant temperature (i.e., 80 to 120°C), were run at 10°C/min. Two peaks were observed in the case of the epoxy excess but only one for the stoichiometric formulation: the peak at low temperature was attributed to the epoxy copolymerization with the anhydride while the peak at high temperature was attributed to the epoxy homopolymerization. The catalytic effect of the OH groups present in the epoxy monomer on the copolymerization reaction was demonstrated by the decrease in the activation energy of the propagation step when increasing the epoxy excess. There is a catalytic effect of the copolymerization product on the homopolymerization reaction. Our simplest model, proposed previously for a catalyzed epoxy/anhydride system [J. Polym. Sci. Part B: Polym. Phys. Ed., 37, 2799 (1999)], can be used to fit both isothermal and dynamical kinetic data. Fil: Mauri, Adriana Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Riccardi, Carmen Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina

The present thesis deals with the synthesis and the properties of alternating poly(ester amide)s based on a,w-amino alcohols and cyclic anhydrides. The synthesis of the poly(ester amide)s is performed by polycondensation of linear AB-monomers (a-carboxyl-w-hydroxy amides), in some cases additionally by ring-opening polymerization of cyclic ester amides. The correlation between the structure of the poly(ester amide)s and their properties is discussed. Furthermore, mechanistic and kinetic aspects of the ring-opening polymerization of cyclic ester amides are investigated. The synthesis of AB- and ABA-block copolymers using poly(ethylene oxide) macroinitiators is described.

In previous publications we reported the synthesis and characterization of silsesquioxanes derived from the hydrolytic condensation of (3-glycidoxypropyl) trimethoxysilane (GPMS) using diglycidylether of bisphenol A (DGEBA) as a solvent [1,2]. The reaction product has aliphatic epoxy groups supplied by the silsesquioxane and aromatic epoxy groups supplied by the solvent. Solutions containing 0, 25 and 50% aliphatic epoxy groups, were cured with different hardeners: methyltetrahydrophthalic anhydride (MTHPA), ethylenediamine (EDA) and benzyldimethylamine (BDMA). Silsesquioxane-modified epoxy networks showed a significant increase in the elastic modulus in the rubbery state, the abrasion resistance and the development of strain hardening in uniaxial compression tests. Fil: Mauri, Adriana Noemi. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina Fil: Riccardi, Carmen Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Williams, Roberto Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina