Search

Ethylene‐octene copolymer (EOC, three EOCs with different octene content used in this study) and propene‐ethylene copolymer (EPC, three EPCs with different ethylene content used in this study) can have effects on the crystallization dynamics, crystal structure, and foaming properties of ethylene‐vinyl acetate copolymer (EVA). For unfoamed EVA/EOC and unfoamed EVA/EPC blends, both EVA/EOC and EVA/EPC blends show phase separation structure. The foam cells in EVA/EOC blends have better uniformity compared to those in EVA/EPC blends, which result from the better compatibility of EVA and EOC than EVA and EPC obtained from the morphology analysis. For the blends with different crystallization ability of EOC or EPC, the blends with lower crystallinity has more uniform cell distribution than blends with higher crystallinity, due to the crystallization zone cause heterogeneous crosslinking and foaming of the blend. Both EOC and EPC can impart higher elasticity to EVA foamed materials. EOC was found to be more suitable for blending with EVA for foamed materials, offering the potential to obtain EVA/EOC foamed materials with excellent performance. Highlights: Ethylene‐octene copolymer with higher octene content has better effect on foaming property of ethylene‐vinyl acetate copolymer than ethylene‐propylene copolymer.Ethylene‐propylene copolymer can decrease the foaming temperature of ethylene‐vinyl acetate copolymer.A mechanism of foaming for ethylene‐vinyl acetate copolymer/semi‐crystallized polymer blends is proposed.Achieved in‐depth understanding of structure–property relationship about ethylene‐vinyl Acetate copolymer/polyolefin elastomer foamed material. [ABSTRACT FROM AUTHOR]

In this study, an innovative approach is developed for fabricating formamidinium lead triiodide (FAPbI3) quantum dots (QDs) by substitution of octadecene (ODE). The results showcase the formation of superior‐quality FAPbI3 QD films, boasting enhanced photoluminescence (PL) and transport properties. Specifically, ODE has been replaced with octene (OCE), a shorter linear alpha olefin. Comparisons are drawn between the novel synthesis method and the conventional ODE‐based QD films, scrutinizing their optical properties and applicability in QD solar cells. The outcomes highlight distinctions in temperature‐dependent PL emission characteristics, revealing an unprecedented absolute PL QY of up to 84%, a notable improvement from the 70% achieved with ODE, along with enhanced transport properties. Furthermore, the performance of both systems in QD solar cells is evaluated for two values of layer thickness, 100 and 200 nm, to investigate the transport properties at the device level. The results exhibit a remarkable improvement from 200% to 150% in average power conversion efficiency (PCE) and consistently higher values for open‐circuit voltage and short‐circuit current density for the OCE‐based solar cell compared to an ODE‐based counterpart for both thickness values, reaching a striking 6.7% PCE for the best‐performing device despite the nonideal conditions. [ABSTRACT FROM AUTHOR]

An approach towards incorporating varied degrees of steric profiles around the ligand's backbone, which were envisaged to alter the catalytic paths leading to targeted 1-C8/1-C6 olefin products, were explored. Cr-pre-catalysts designed with PNP ligands comprising a fused aryl moiety were delivered at a relatively higher C8 olefin selectivity (up to 74.6 wt% and C8/C6 of 3.4) when the N-connection to the aromatic unit was placed at the 2-position. A relatively higher C6 olefin selectivity (up to 33.7 wt% and C8/C6 of 1.9) was achieved with the PNP unit anchored at the 1- or 6-position. Based on detailed catalytic studies, we confirm the fact that by introducing a controlled degree of bulkiness on the N-site through a judicious selection of the N-aryl moiety of different sizes, the selectivity of the targeted olefin product could be tuned in a rational manner. [ABSTRACT FROM AUTHOR]

The sampling of odorous emissions is a fundamental step in correctly quantifying odour concentration. Its importance was strongly emphasized in the recent Italian legislation (MASE, 2023), which describes strict constraints for conducting olfactometric sampling. In particular, for point sources, it is necessary to assess the variability of the source to evaluate any spikes in emissivity and then sample consistently with the trend of this emissivity. Therefore, this study aims to conduct a field sampling campaign that meets the criteria mentioned in the Italian recent directive, combining olfactometric sampling with continuous monitoring of the source using portable PID instrumentation. The results obtained during this preliminary monitoring campaign highlight that the variability in VOC emissions is not strictly correlated with potential variability in terms of odour concentration. Indeed, despite the variations observed in continuous measuring at the source, the odour concentration measurements remained stable throughout the monitoring period. Chemical speciation of samples identified high concentrations of propene, varying in accordance with PID reading, while the odour potential was primarily due to lower concentrations of octene and nonene, which remained relatively constant. These results indicate that continuous monitoring emission variability does not necessarily translate into odour concentration variability. [ABSTRACT FROM AUTHOR]

A ethylene - octene copolymer (OBC)/waste polystyrene (WPS) compatibilizing masterbatch was prepared through the Friedel-Crafts alkylation reaction. The effects of anhydrous; AlCl3 dossage on the grafting rate of WPS and the properties of the masterbatch and the effects of the masterbatch dosage on the comprehensive performance of ethylene -propylene-diene rubber (EPDM) were investigated. The results indicated that WPS could react with OBC to form an OBC-g-WPS graft copolymer. There was no gelation at an anhydrous AlCl3 dosage of 0. 4 and a WPS grafting rate of 25. 3 wt%, resulting in the best comprehensive properties of the masterbatch. When this compatibilizing masterbatch was used for EPDM, the resultant rubber exhibited higher tensile strength, higher tear strength, and better heat aging resistance than pure EPDM vulcanized rubber, and its performance was also better than that of the EPDM containing the same amount of an OBC/WPS physical blend. Scanning electron microscopy indicated that WPS was uniformly dispersed in the vulcanized EPDM rubber with the addition of the OBC/WPS compatibilizing masterbatch. [ABSTRACT FROM AUTHOR]

Application of molecular electron density theory (MEDT) to investigate the [5+2] cycloaddition reaction between oxidopyrylium and ethervinylether, we discovered that oxidopyrylium is an electrophile and ethervinylether is a nucleophile by an examination of conceptual DFT indices. Analysis of energetical parameters shows clearly that this cycloaddition is both regio- and stereoselective, which is extremely consistent with the experience. Topological analysis of the electron localization function (ELF) has shown that this [5+2] cycloaddition is achieved by a two-step, single-step mechanism along the most favored route. Aside from that, docking outcomes show that the (1–20) oxabicyclo[3.2.1]octene derivatives have a significant anti-HIV potential. [ABSTRACT FROM AUTHOR]

In the article, an ionic liquid catalytic system based on diethylamine hydrochloride and aluminum chloride (AlCl3), which meets the concepts of "Green Chemistry," is synthesized as an object of study. The process of 1 - octene oligomerization was carried out in the presence of synthesized ionic liquid catalyst systems. The structure, chemical composition and physicochemical properties of fractions obtained by oligomerization were studied. As a result of experimental studies, fractions above 3500C were obtained and have high quality indicators. [ABSTRACT FROM AUTHOR]

In this work, new partially substituted derivatives of octa(3-thiopropyl)silsesquioxane (SSQ-8SH) were synthesized. The article compares the thiol-ene reaction using two methods: radical mechanism, thermally initiated (AIBN), and in the presence of a photoinitiator (DMPA). Both the crystalline and the oil forms of SSQ-8SH were functionalized. Olefins with nonpolar alkyl groups (hexene, octene, and octadecene) and vinyltrimethoxysilane, allyl glycidyl ether, allyl 2,2,3,3,4,4,5,5-octafluoropentylether, allyl methacrylate, and styrene were used in the reactions, allowing to obtain seven new derivatives. All compounds were characterized using spectroscopic (1H NMR and 29Si NMR) and spectrometric (MALDI-TOF-MS) methods. The influence of functional groups on the water contact angle value was determined. The functionalization of the compound led to a contact angle value above 95° (SSQ-4SH-4OD). Density measurements and thermogravimetric analysis (TGA) were carried out for all compounds. The highest onset temperature (357.4 °C) and temperature at the maximum mass loss rate (377.3 °C) were observed for SSQ-SH-4OD. The addition of alkyl groups significantly decreased the density of compounds with increasing chain length (1.198 g/cm3; 1.162 g/cm3; 1.095 g/cm3 for hexene, octene, and octadecene, respectively). Silsesquioxanes have potential applications in various materials, such as UV-curable resins, allowing to modify, for example, their surface properties. Modification of a commercial photocurable resin with selected derivatives was carried out to determine the impact on physicochemical properties (TGA, WCA). [ABSTRACT FROM AUTHOR]

Four highly oxidized pimarane diterpenoids were isolated from Kaempferia takensis rhizomes. Kaemtakols A–C possess a tetracyclic ring with either a fused tetrahydropyran or tetrahydrofuran motif. Kaemtakol D has an unusual rearranged A/B ring spiro-bridged pimarane framework with a C-10 spirocyclic junction and an adjacent 1-methyltricyclo[3.2.1.02,7]octene ring. Structural characterization was achieved using spectroscopic analysis, DP4 + and ECD calculations, as well as X-ray crystallography, and their putative biosynthetic pathways have been proposed. Kaemtakol B showed significant potency in inhibiting nitric oxide production with an IC50 value of 0.69 μM. Molecular docking provided some perspectives on the action of kaemtakol B on iNOS protein. [ABSTRACT FROM AUTHOR]

The shape memory (SM) polymers with superior SM properties were successfully fabricated based on melt blending of natural rubber (NR) and ethylene octene copolymer (EOC) at various crystallinity of EOC phase. The differential scanning calorimetry analysis, mechanical properties, temperature scanning stress relaxation, and shape memory properties were studied. Results revealed that the mechanical and thermal properties of the prepared NR/EOC blends improved as a function of amount of ethylene fraction in the EOC phase. The ethylene segment of EOC in the NR/EOC blend is triggered as a stimulus-sensitive domain. The shape memory properties in terms of shape fixity and shape recovery efficiencies of the blends tended to increase with the increasing of crystalline segments in the blends. The shape memory properties of the prepared blends substantially exceed the best performance (close to 100%) by blending the NR/EOC at 50/50 parts by weight, having 62%–80% of ethylene content in the EOC phase, which corresponds to approximately 3°–16° of crystallinity of EOC phase in the blends. [ABSTRACT FROM AUTHOR]

Blending octene random copolymer (ORC) with other polymers is a promising approach to improving ORC mechanical properties, such as tensile strength and elongation. In this study, octene block copolymer (OBC) with lower density than ORC and high-density polyethylene (HDPE) were used to blend with ORC. The effect of both OBC and HDPE on ORC was analyzed using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and small-angle X-ray scattering (SAXS). For ORC/OBC blends, a small amount of OBC can improve the crystallization ability of ORC. Meanwhile, for ORC/HDPE blends, the crystallization ability of ORC was significantly suppressed, attributed to good compatibility between ORC and HDPE as indicated by the homogeneous morphology and the disappearance of the α transition peak of ORC in ORC/HDPE blends. Therefore, the tensile strength and elongation of ORC/HDPE blends are significantly higher than those of ORC/OBC blends. For ORC/OBC/HDPE ternary blends, we found that when ORC:OBC:HDPE are at a ratio of 70:15:15, cocrystallization is achieved. Although HDPE improves the compatibility of ORC and OBC, the three-phase structure of the ternary blends can be observed through SAXS when HDPE and OBC exceed 30 wt%. Blending HDPE and OBC (≤30 wt%) could improve the mechanical property of ORC. [ABSTRACT FROM AUTHOR]

With the development of degradation technologies such as chemical‐catalysis and bio‐catalysis, starch‐polyethylene (PE) composites have been revitalized as industrial packaging materials. However, starch and PE suffer from interfacial incompatibility. In this study, poly(octene ethylene) grafted glycidyl methacrylate (POE‐g‐GMA) was added at relatively low amounts (0–7 wt%) to construct robust structures between thermoplastic starch (TPS) and low‐density polyethylene (LDPE). Tensile strength increased by 36.39% with the addition of 1 wt% POE‐g‐GMA. Meanwhile, a smooth surface was observed by SEM, and a fibrillar cross‐linked structure appeared on the fractural surface of the blend. POE‐g‐GMA formed a stable "bridge" at the interface between TPS and LDPE, which increased the thermal stability of the blend as well. The crystallinity of LDPE increased from 20.5% (without addition) to 32.8% (with 1 wt% addition), whereas the average crystallite size decreased slightly. The optimal POE‐g‐GMA content was found to be 1 wt% based on mechanical and thermal measurements. The results of this study can provide a reference for improving the interfacial compatibility of biopolymers and fossil‐fuel‐based polymers. [ABSTRACT FROM AUTHOR]

A short and efficient synthetic access to functionalized compounds displaying major structural elements of the natural product populusone is elaborated by exploiting a diastereoselective Mukaiyama aldol addition followed by a triflic anhydride-induced oxa-Michael addition to construct the sensitive 2-oxa-bicyclo[2.2.2]octene unit as an enol triflate, which is directly used in a subsequent Suzuki cross-coupling. While attempts to close the strained 10-membered ring by means of Ru-catalyzed ring-closing metathesis were not successful, the developed synthetic scheme opens a rapid synthetic access to advanced intermediates, which may allow the completion of the total synthesis of populusone in the future. [ABSTRACT FROM AUTHOR]

Irradiation of 1‐(penta‐3,4‐dienoyl)indole derivatives in the presence of an aromatic ketone by a high‐pressure mercury lamp through Pyrex glass gave two types of cyclized products stereoselectively in high combined yields. The major product was a tetracyclic indoline derivative containing anti‐Bredt‐type azabicyclo[4.2.0]octene moiety produced via photo [2+2] cycloaddition between indole and a distal double bond of allene, accompanied by a small amount of proximal [2+2] adduct. Among a range of aromatic ketones screened, 3′,4′‐methylenedioxyacetophenone was found to sensitize the substrate most effectively. [ABSTRACT FROM AUTHOR]

The selective hydrogenation of octyne in a mixed 1‐octyne/1‐octene feed was investigated by employing Pd/Al2O3 and PdAg/Al2O3 catalysts coated with 1‐butyl‐3‐methylimidazolium dicyanamide ([BMIM][DCA]) as SCILLs (Solid Catalysts with an Ionic Liquid Layer). All SCILLs were compared to an organically modified, 1‐ethylimidazole (EIM) coated catalyst to determine if there is a SCILL effect. Results of the catalysis showed that both uncoated catalysts were highly active (100 % 1‐octyne and 1‐octene conversion) in the hydrogenation reactions with dominant selectivity towards octane. No increase of 1‐octene in the reactor outflow (octene gain) was noted. Coating 1Pd/Al2O3 with [BMIM][DCA] at four monolayers (ML) corresponding to a surface loading of 45 wt% still gave 100 % octyne conversion but now with a 54 % 1‐octene gain, as no octene was converted. Coating 1Pd9Ag/Al2O3 with only a single monolayer of [BMIM][DCA] (14 wt%) was sufficient to give a 1‐octene gain of 84 % at an octyne conversion of 91 %. Time‐on‐stream reactions for the uncoated and SCILL systems showed stable operation during the experiments. [ABSTRACT FROM AUTHOR]

• A bottom-up approach has been developed to readily immobilize TEMPO catalytic redox sites on the pore surface of porous aromatic framework. • The porous PAF-TEMPO catalyst with homogeneously dense distributed TEMPO groups facilitates high efficiency of the electrocatalysis. • The established catalytic system can deliver water-based oxidation to avoid the use of toxic oxidants or additives for green chemical processes. • The electrocatalysis can achieve oxidation of cyclooctene to valuable epoxycyclooctene in 89.7 % yield and 90.3 % selectivity. The development of economically viable and environmentally benign oxidation reaction systems with high selectivity and efficiency is a key focus in synthetic chemistry. Utilizing water as an oxygen source, alongside an anodic system for converting water to oxygenated compounds, represents an atom-economical and sustainable strategy for highly selectively synthesizing epoxides. Herein, we synthesized a novel porous aromatic framework with TEMPO radicals uniformly immobilized on the pore surface by a synthetic bottom-up approach (PAF-TEMPO). Strategically grafting TEMPO catalytic sites, which results in a highly dense and uniform dispersion, promotes extensive reactant contact, thereby enhancing catalytic efficiency. The PAF-TEMPO catalyst demonstrated efficient electrocatalytic activity for cyclooctene oxidation to cyclooctene oxide, achieving 89.7 % yield and 90.3 % selectivity with good recyclability. This work will give inspiration for novel electrocatalyst design and development of green and sustainable catalytic systems. A TEMPO-functionalized porous aromatic framework has been readily synthesized as electrocatalyst for oxidation of cyclooctene to cyclooctene oxide, achieving 89.7 % yield and 90.3 % selectivity with good recyclability. [Display omitted] [ABSTRACT FROM AUTHOR]

The role of cyclodextrins in accelerating the reaction rate in biphasic hydroformylation: Cyclodextrins facilitate the transport of the substrate 1-octene from the organic bulk phase to the liquid–liquid interface and simultaneously remove the product nonanal from the interfacial region. [Display omitted] • Water based biphasic hydroformylation assisted by cyclodextrins. • Examined for the first time using an in-situ image-based boroscopic technology. • RAME-β cyclodextrins increased the a LL by 84 % • Kinetic study showed that RAME-β cyclodextrins reduce the rate limiting effect of the nonanal concentration. • Increasing RAME-β cyclodextrins concentration decrease dependency of the reaction rates on the conversion progress. Water based biphasic hydroformylation assisted by cyclodextrins is known for enhanced reaction rates in comparison to the non-assisted biphasic hydroformylation. In this paper, the liquid–liquid interface of the hydroformylation of 1–octene, enhanced by randomly methylated-β cyclodextrins (RAME-β cyclodextrins), was examined for the first time using an in-situ image-based boroscopic technology. This technique enables the observation of the liquid–liquid interfacial area (a LL) during the reaction and under reaction conditions, facilitating an explicit analysis of the droplet population. In this study defined mixtures of the reaction components with RAME-β cyclodextrins increased the a LL by 84 %. A kinetic study showed that RAME-β cyclodextrins reduce the rate limiting effect of the nonanal concentration in the two phasic water/octene system on the interphase. The kinetic expression shows consequently higher reaction rates for this three-phase conversion, leading to a 387 % increase in aldehyde yield. When comparing four different amounts of RAME-β cyclodextrins (n CD :n Rh(acac)(CO)2 = 0 / 12:1 / 24:1 / 50:1), we observed a decreasing dependency of the reaction rates on the conversion progress and therefore on the nonanal formation for higher cyclodextrin concentrations. A recovery test of the aqueous phase involving nonanal and 1-octene reveals a drastically increased concentration of 1029 % 1-octene (c octene = 1.08 10-3 mg mg−1) and 13676 % nonanal (c nonanal = 14.41 10–3 mg mg−1) after the addition of 0.002 mol RAME–β cyclodextrins. These findings affirm that RAME-β cyclodextrins primarily remove nonanal from the interfacial region while facilitating an increased availability of 1-octene for the surface bound reaction. [ABSTRACT FROM AUTHOR]

The effect of particle size as well as of coke formation on conversion of intermediate chain length paraffins (C6–C9) to the corresponding olefins was investigated on a promoted Pt catalyst with the model substance n‐octane. Increasing the particle size leads to pore diffusion limitations and thus to a reduction of the activity for paraffin conversion and of the octene selectivity caused by more pronounced formation of consecutive products (aromatics, octadienes). Both effects are adequately predicted by the developed kinetic model. The activity of dehydrogenation declines with the content of coke, but to a lesser extent than the rate of coke formation, which is beneficial regarding the catalyst lifetime. The initial activity is fully recovered by mild coke burn‐off (T < 470 °C). [ABSTRACT FROM AUTHOR]

An efficient gold [Au]‐catalyzed one‐pot synthesis has been developed for the construction of biologically interesting mono‐ and bipyridines by utilizing the commercially available cyclic ketones and propargylamine in a sealed tube. The formation of bipyridine derivative 21 a indicates that annulation followed by retro‐Diels–Alder reaction is occurring with norbornene system. However, keto‐derivatives containing bicyclo[2.2.2]octene system 25 indicate that retro‐Diels–Alder reaction is not facile. Compounds 32 a and 33 a were subjected to ring opening cross‐ metathesis to generate diversity and further functionalization of pyridine derivatives. [ABSTRACT FROM AUTHOR]

Philippe de Clermont (1831–1921) was a French organic chemist, known particularly for his synthesis of tetraethyl pyrophosphate, the first organophosphate cholinesterase inhibitor. This achievement was part of an extensive research about phosphoric ethers using Wurtz’s procedure. This type of synthesis was found to be also appropriate for the preparation of carbonic ethers. Another important consequence was that the reaction between ammonia and an ether composed of a mineral oxacid resulted in the formation of an alcoholic alkali. Clermont also carried extensive research about octene and its derivatives that culminated in the synthesis of a large number of new derivatives, among them octylene oxide acetate, caprylene halides and alcohol, octyl glycol, octyl glycol chlorhydrin, etc. Clermont determined the composition of persulfonic acid, synthesized sulfophenylurea, and a variety of thioureas. He also studied a variety of reactions of pyruvic acid, the composition of pyrogallic acid, synthesized purpurogallin, and a variety of metallic sulfides, in particularly the flesh and green sulfides of manganese and the decomposition reaction of ammonium chloride with metallic sulfides. Likewise, he showed that the production of aurin required the presence of nascent CO2. [ABSTRACT FROM AUTHOR]

This study was designed to investigate the effect of molar ratio of 1-octene and type as well as concentration of Lewis acids on the free radical copolymerization of butyl methacrylate (BMA) with 1-octene. The synthesized copolymers have been substantially described by FTIR, 1H NMR, GPC and DSC. The quantitative 1H NMR and GPC demonstrated that by increase in the molar ratio of 1-octene and Lewis acids to BMA, the incorporation of 1-octene in the copolymer backbone enhanced, Mn reduced and polydispersity became narrower. The maximum incorporation of 1-octene (13.7%) was observed for sample CSC7 having [1-octene/BMA] of 3 mol% and [AlCl3/BMA] of 1.5 mol%. The DSC results confirmed the NMR and GPC outcomes, suggesting a decrease in Tg by increasing 1-octene in the copolymer backbone. Moreover, it is found that temperature has a remarkable influence on the copolymerization behavior. The results also showed that by substituting the acrylate monomer from butyl methacrylate to butyl acrylate, the incorporation of 1-octene increased. [ABSTRACT FROM AUTHOR]

The emergence of SARS-CoV-2, responsible for the global COVID-19 pandemic, requires the rapid development of novel antiviral drugs that would contribute to an effective treatment alongside vaccines. Drug repurposing and development of new molecules targeting numerous viral targets have already led to promising drug candidates. To this end, versatile molecular scaffolds with high functionalization capabilities play a key role. Starting with the clinically used conformationally flexible HIV-1 protease inhibitors that inhibit replication of SARS-CoV-2 and bind major protease 3CLpro, we designed and synthesized a series of rigid bicyclo[2.2.2]octenes fused to N-substituted succinimides to test whether this core scaffold could support the development of non-covalent 3CLpro inhibitors. Inhibition assays confirmed that some compounds can inhibit the SARS-CoV-2 main protease; the most promising compound 11a inhibited 3CLpro in micromolar range (IC50 = 102.2 μM). Molecular simulations of the target-ligand complex in conjunction with dynophore analyses and endpoint free energy calculations provide additional insight and first recommendations for future optimization. The fused bicyclo[2.2.2]octenes can be used as a new potential starting point in the development of non-covalent SARS-CoV-2 3CLpro protease inhibitors and the study also substantiates the potential of this versatile scaffold for the development of biologically active molecules. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] • A micro-kinetic model was constructed for the ethylene oligomerization. • Hexene is formed via a series of ethylene coordination-insertion steps. • Octene is formed via co-oligomerization of ethylene and desorbed butene. We report the kinetics of ethylene oligomerization over the Ni-H-Beta for temperatures ranging between 50 and 100 °C and pressures ranging between 5 and 28 atm. According to our results, the apparent activation energies involved in the formation of butene, hexene, and octene are 44, 78, and 60 kJ.mol−1, respectively. The measured lower apparent activation energy for butene formation relative to hexene and octene is a likely result of the fact that the measured butene formation is not the true (forward) rate of formation of butene but it the net rate because of the consumption of butene in secondary reactions. Analysis of the reaction order indicates that participation of butene in chain-growth reactions takes place via desorption followed by re-adsorption of butene on the catalyst. The results also indicate that hexene undergoes a similar process. In the present paper, we refer to the pathway involving co-oligomerization of butene and hexene as "cascade co-oligomerization". Based on these findings, we proposed a reaction network and modeled reaction rate expressions for ethylene consumption and butene, hexene, and octene formation based on the construction of a micro-kinetic model. We calculated the kinetic parameters involved in the reaction network proposed and found evidence that the formation of octene proceeds mainly via the "cascade co-oligomerization" of re-adsorbed butene with ethylene. [ABSTRACT FROM AUTHOR]

Maleic anhydride grafted ethylene octene copolymer toughened acrylonitrile butadiene styrene/polyamide 6 composites, strengthened with varying amounts of E-glass fibre (EG) were successfully developed via compounding technique. The tribological investigations of compounded composites support excellent wear resistance potential of glass fibre, with 15 wt% EG reinforced composites displaying ∼10 times superior wear resistance. While, mechanical performance evaluation validates the strengthening abilities of EG, with tensile strength and tensile modulus displaying a substantial improvement. The microstructure of worn composite surfaces, characterised by scanning electronic microscopic studies suggest the inherent ability of glass fibre in PA6 matrix to enact the role of reinforcements by choice. [ABSTRACT FROM AUTHOR]

Polymer nanocomposites based on a layered clay used as nanofiller and copolymers ethylene and vinyl acetate matrix (EVA, the content of vinyl acetate (VA) component 19 wt% and 5 wt%) and ethylene octene copolymer (EOC, 17% and 45% of octene) were prepared. KO Buss kneader and double screw extruder were used. The MMT Na+ and four types of commercial products such as Nanofil N5 and N3000, Cloisite 93A and 30B were used as nanofillers--5 wt% in relation to the content of montmorillonite. The aim was to evaluate the influence of copolymer composition and processing on prepared nanocomposite properties. The morphology of samples was examined by means of X-ray diffraction (XRD) and transmission electronic microscopy TEM. Furthermore, mechanical and especially barrier properties were observed. Despite the fact that the XRD and microscopy results have revealed that complete exfoliation did not take place in any case, mechanical properties as well as the permeability showed that used 5 wt% of clay was enough to achieve the improvement of properties. Cloisite 30B might be the most suitable for the polyethylene/EVA matrix. In case of EOC copolymer the nanofiller Nanofil N3000 and mainly Cloisite 93A seems to be more suitable. The better properties were achieved for the version of EVA with lower VA content and also for EOC 17, but not for each evaluated property., INTRODUCTION Copolymers are systems whereby the presence of two or more monomers in the polymer mixture creates a polymer chain where the individual mers are present in different rank. The [...]

In this work, the [beta]-nucleated isotactic polypropylene (iPP)/ ethylene-octene copolymer (POE) blends demonstrated greatly enhanced impact toughness by adding traces of carbon nanotubes (CNTs) (only 0.05 wt%). When the POE content was 30 wt%, the impact strength of [beta]-nucleated iPP/POE blends with CNTs was as high as 51.7 kJ/[m.sup.2], about 5.6 kJ/[m.sup.2] higher than [beta]-nucleated iPP/POE blends, 15.2 kJ/[m.sup.2] higher than CNTs-filled iPP/POE blends, and almost 19 times of pure iPP sample. This significantly improved impact toughness was considered to be attributed to the shear yielding and multiple-crazing, originating from the presence of abundant [beta]-crystals in the iPP matrix, the enhanced mobility of the molecular chains in the confined amorphous region of iPP lamellae and the homogenous distribution of POE dispersed phase with a small size, indicating the synergistic effect of CNTs, [beta]-nucleating agent and POE on the toughness of iPP., INTRODUCTION As a general plastic, isotactic polypropylene (iPP) is widely used in our daily life from common packaging and textile products to components in cutting-edge automobiles and aircraft, due to [...]

The localization of multiwall carbon nanotubes (MWCNTs) in the immiscible blends of ethylene-1-octene copolymer (EOC) and cyclic olefin copolymer (COC) with the sea-island morphology and electrical conductivity of resulting nanocomposites were investigated. Depending on the feeding orders, as the MWCNTs were located in the COC droplet, the electrical conductivity was obtained as high as 5.71 x [10.sup.-7] S/cm, while the MWCNTs were located in EOC/COC interface, the electrical conductivity increased significantly up to 1.72 x [10.sup.-2] S/cm. The improved electrical conductivity in EOE/COC/MWCNTs nanocomposite is attributed to the interfacial localization of MWCNTs which is resulted from thermodynamic affinity of MWCNTs to COC, as well as an interconnected structure via deformed and swelled COC droplets. Thermodynamic affinity of MWCNTs to COC and established interconnected structure are confirmed by rheological characterization, microscopic observations, dynamic mechanical analysis, and electrical conductivity measurements. Therefore, as a result of selective localization of MWCNTs and well-designed phase morphology, lower rheological and especially electrical percolation thresholds could be obtained in the ternary nanocomposites compared to the binary systems. POLYM. ENG. SCI., 59:447-456, 2019., INTRODUCTION Polymer nanocomposites have attracted a considerable research interest because of their remarkable properties, including enhanced physical properties, electrical, magnetic, optical, and thermal characteristics [1,2]. Carbon nanotubes (CNTs) have proved [...]

Efficient and reliable synthesis of substituted hydrazinylpyridines in thick-wall ACE tubes via nucleophilic substitution of a chlorine substituent in different chloropyridines is presented. Hydrazine hydrate and alkylhydrazines were used as nucleophiles and simple alcohols and diethyl ether were the only organic solvents necessary, making the process environmentally and user friendly, potentially reaching 100% atomic efficiency. In the next step, transformations of succinic anhydride moieties fused to the bicyclo[2.2.2]octene framework into succinimide moieties via nucleophilic substitution of oxygens were conducted. As nucleophiles two of the synthesized hydrazinylpyridines (2-hydrazinyl-3-nitropyridine and 2-hydrazinyl-5-nitropyridine) and also hydrazine hydrate, phenylhydrazine, and 4-nitrophenylhydrazine were used. Reactions were again carried out in ACE tubes and only simple alcohols, diethyl ether, and acetone were needed as solvents. One of the prepared bicyclo[2.2.2]octene adducts displayed water solubility thus being a promising candidate for future studies as a novel bidentate ligand for various metal cations in aqueous solutions or acting as an unprecedented halogen bond acceptor. [ABSTRACT FROM AUTHOR]

UTKO1 is a synthetic analog of a natural tumor cell migration inhibitor, moverastin, isolated from microbial extracts of Aspergillus sp. 7720. UTKO1 was initially developed as a mixture of the stereoisomers. In this study, a concise and unified synthesis of the 4 optically active stereoisomers of UTKO1 was achieved from a known optically pure dihydro-α-ionone through a 5-step sequence. The key transformation in the synthesis was a Nozaki–Hiyama–Kishi (NHK) reaction between an optically active enoltriflate and a known aldehyde to install the chiral allylic hydroxy group at C2′. Simple chromatographic separation of the 2 diastereomers with regard to the allylic hydroxy group was possible by the derivatization into the corresponding acetals with Nemoto's optical resolution reagent, (S)- or (R)-5-allyl-2-oxabicyclo[3.3.0]octene (ALBO). All 4 synthetic stereoisomers of UTKO1 exhibited comparable tumor cell migration inhibitory activity. [ABSTRACT FROM AUTHOR]

β-Ketophosphonates, with the keto group linked to a bicyclo[3.3.0]oct(a)ene fragment, were synthesized starting from two diacids. These diacids were first transformed into internal anhydrides and one into a diester. The anhydrides and the diester were reacted with the lithium salt of dimethyl methanephosphonate to give two carboxy β-ketophosphonates, an ester β-ketophosphonate and a bis β-ketophosphonate in good yield. The ester β-ketophosphonate, obtained by two routes was used in the E-HEW selective olefination of a prostaglandin aldehyde with an α-side chain to give the 15-keto prostaglandin analogue in good yield. The compounds were characterized by elemental analysis, IR and high resolution 1H- and 13C-NMR spectroscopies. [ABSTRACT FROM AUTHOR]

Olefin metathesis of α‐olefins (C6, C8, C10), α, β‐unsaturated ester, α, β‐ unsaturated acetate and cross‐metathesis of 1‐octene and ethyl 6‐heptenoate were carried out using well‐defined [(≡Si−O−)W(CH3)5] and [(≡Si−O−)Mo(≡CtBu)(CH2tBu)2] pre‐catalysts. During the reaction, it was observed that irrespective of the chain length, linear α‐olefins are almost showing similar TON. We observed that Mo pre‐catalyst performs better with TONs between 700 and 1478 as compared to W with TONs between 213 and 962 at room temperature. Both pre‐catalysts performed equally at 70 °C, with almost similar activity as well as TON (≈1700). We also carried out self‐metathesis of functionalized olefins using both silica‐supported W and Mo pre‐catalysts. It was observed that W pre‐catalyst performs much better than Mo pre‐catalyst for functionalized olefin metathesis reaction in our conditions. Additionally, we noticed that W pre‐catalyst provides selective metathesis product, whereas Mo pre‐catalyst gives a range of products due to the isomerization of the olefinic bond. [ABSTRACT FROM AUTHOR]

The recycled polypropylene (RPP) and ethylene-octene copolymer (POE) were used as the main raw materials. The RPP/POE blends were prepared by melt blending method. The mechanical properties and thermal properties of RPP/POE blends as well as the effect of compatibilizers on the mechanical properties were studied. The results showed that with the increase of POE addition, the tensile strength and impact strength of RPP/POE blends increased at first and then decreased, elongation at break tended to increase first and then stabilize, but the flexural strength decreased gradually. When the addition of POE was 5%, the tensile strength of the blend reached its maximum 16.7 MPa. When the addition of POE exceeded 20%, the elongation at break reached 400%, the impact strength increased to 5 times of that of RPP, and the flexural decreased to 50% that of RPP. Furthermore, the Vicat softening temperature of the blends decreased with an increase of the POE addition, and the introduction of POE had a little influence on the crystal structure of RPP, but had a baffling effect on the crystallization of RPP. Moreover, compared with PP-g-MAH, compatibilizer POE-g-MAH was more suitable for improving the strength and toughness of RPP/POE blends. [ABSTRACT FROM AUTHOR]

Flame‐retardant blends of polyethylene‐octene elastomer (POE) and natural rubber (NR) filled with expandable graphite (EG) were melt‐mixed with azodicarbonamide to prepare elastomeric foams. The effect of the NR incorporation on the properties of EG filled POE foam was investigated. Gel content and microstructure observations revealed that the addition of NR into the POE/EG blend induced change in molecular structure, which produced a finer cellular structure during foaming. The compressive strength and elastomeric recovery of the POE/NR/EG blend foams were found to increase with increasing NR content. Based on the limiting oxygen index and horizontal burning measurements, all the POE/NR/EG blend foams were found to have good flame‐retardant properties. On the other hand, these POE/NR/EG blend foams exhibited higher combustion rates with an increasing NR content under high heat radiation and temperature in a cone calorimeter test. This study demonstrates that the combined use of NR as a modifier and EG as a flame retardant in POE foams provides an effective and practical method of obtaining well‐balanced improvements in cellular structure, mechanical properties, and flame resistance. [ABSTRACT FROM AUTHOR]

Comparative studies (gel permeation chromatography and evaluation of turbulent drag reduction effectiveness on a turbulence rheometer) of ultra-high molecular weight polymers from a series of higher alpha-olefins (hexene, octene, decene, dodecene) used as hydrodynamic drag agents have been carried out. It was found that the activity of hexene in the polymerization on a titanium magnesium catalyst, if all other relevant factors remain unaltered, significantly exceeds the activity of octene, decene, and dodecene (the conversion of hexene in 24 h is almost 1.5 times higher than the conversion of other monomers over the same time), and the rates of polymerization of the latter differ slightly. The average molecular weights of all polymers differ only slightly: ~6 millions Da for polyhexene and ~5 millions Da for all the others. At the same time, the drag reduction effectiveness of the polymers showed a significant dependence on the nature of the initial monomers: the drag reduction effectiveness rapidly diminishes with an increase in the molecular weight of the corresponding alpha-olefin (3–4 times upon transition from polyhexene to polydodecene). [ABSTRACT FROM AUTHOR]

[Display omitted] • Covalent adaptable networks were made from multi-block ethylene/1-octene copolymers. • OBC CANs are robust and reprocessable from dialkylamino disulfide dynamic chemistry. • Crystallinity in OBCs correlates with cross-link density in CANs and thermosets. • Increasing melt index in OBCs decreases cross-link density in CANs and thermosets. Chain shuttling polymerization has facilitated the rapid development of olefin block copolymers (OBCs) such as ethylene/1-octene multi-block copolymers. The properties of OBCs stem from various parameters such as average block length, number of blocks per chain, etc., which lead to complexity associated with establishing structure–property relationships between precursor OBCs and properties of cross-linked OBCs. Additionally, permanent cross-linking of OBCs sacrifices their recyclability, and cross-linked OBCs capable of being reprocessed have seldom been reported. Here, permanently cross-linked OBCs (OBCXs) and dynamically cross-linked OBCs, or OBC covalent adaptable networks (CANs), were synthesized by melt-state reactive processing of neat OBCs with various crystallinities and melt flow indices (MFIs). The OBC CANs are capable of dialkylamino disulfide dynamic chemistry via the grafting of bis(2,2,6,6-tetramethyl-4-piperidyl methacrylate) disulfide, or BiTEMPS methacrylate, cross-linkers onto OBC backbone chains. Thermomechanical characterizations indicate that increasing crystallinity and decreasing MFI in precursor OBCs lead to higher cross-link densities in OBCXs and OBC CANs. Dynamically cross-linking OBCs into CANs also significantly improves their elevated-temperature creep resistance. Stress relaxation results of OBC CANs indicate an increased average relaxation time with greater cross-link density. Distinct from other CANs capable of dialkylamino disulfide chemistry, the stress relaxation behaviors of OBC CANs of higher cross-link density show evident dependence on their network viscoelasticities. In OBC CANs of lower cross-link density, the dynamic chemistry more strongly governs their stress relaxation behaviors. Finally, the OBC CANs exhibit full cross-link density and thermomechanical property recovery after reprocessing, whereas the OBCXs cannot be reprocessed due to their irreversible cross-links. [ABSTRACT FROM AUTHOR]

Polymer nanocomposites based on a layered clay used as nanofiller and copolymers ethylene and vinyl acetate matrix (EVA, the content of vinyl acetate (VA) component 19 wt% and 5 wt%) and ethylene octene copolymer (EOC, 17% and 45% of octene) were prepared. KO Buss kneader and double screw extruder were used. The MMT Na+ and four types of commercial products such as Nanofil N5 and N3000, Cloisite 93A and 30B were used as nanofillers—5 wt% in relation to the content of montmorillonite. The aim was to evaluate the influence of copolymer composition and processing on prepared nanocomposite properties. The morphology of samples was examined by means of X‐ray diffraction (XRD) and transmission electronic microscopy TEM. Furthermore, mechanical and especially barrier properties were observed. Despite the fact that the XRD and microscopy results have revealed that complete exfoliation did not take place in any case, mechanical properties as well as the permeability showed that used 5 wt% of clay was enough to achieve the improvement of properties. Cloisite 30B might be the most suitable for the polyethylene/EVA matrix. In case of EOC copolymer the nanofiller Nanofil N3000 and mainly Cloisite 93A seems to be more suitable. The better properties were achieved for the version of EVA with lower VA content and also for EOC 17, but not for each evaluated property. POLYM. ENG. SCI., 59:2514–2521, 2019. © 2019 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Laboratory studies have been conducted to explore the possibility of obtaining poly-α-olefin oil PAO-20 under flow conditions on the basis of the domestic industrial octene fraction of α-olefins. The features of cationic oligomerization have been revealed by varying the catalyst concentration and the reaction temperature; process parameters to ensure the maximum yield of desired target product have been determined. [ABSTRACT FROM AUTHOR]

Ag/γ-Al2O3 catalysts, containing 5 and 25 wt% Ag, were synthesized by the slurry phase impregnation method. They were tested for the liquid phase continuous flow preferential hydrogenation of octanal in a mixture with octene. The catalysts were characterised by XRD, IR, BET, SEM, TEM and NH3-TPD. These catalysts showed strong preference for octanal hydrogenation, irrespective of reaction temperature or silver loading. A maximum octanal conversion of 90% with selectivity towards octanol of 94% was achieved over 25 wt% Ag/γ-Al2O3 at 180 °C with minimal octene conversion (< 3%). [ABSTRACT FROM AUTHOR]

Commercial metallocene ethylene–octene random copolymer, Resinex PE RXP 1502 (RXP), was grafted with acrylic or crotonic acid in the solution and in the melt to increase the RXP's polarity and adhesion to cellulose-based substrates. Acrylic or crotonic acids were grafted on the RXP macromolecules which were activated with an oxygen–ozone mixture. The formed graft copolymer was tested as additive to a hot melt adhesive (HMA) improving adhesive properties. The most effective procedure was to graft RXP with acrylic acid in the melt, while grafting activated RXP in a toluene solution was less efficient. The melt grafting efficiency is high and varies between 0.77 and 0.97. The RXP polarity after grafting increases significantly, as there is a 15% decrease in the water contact angle and an increase in the surface energy and its polar component by 1.1–1.7 times as compared to the virgin RXP. The heat-fail temperature resistance in peel of RXP grafted with acrylic and/or crotonic acid increased by more than 10°C, while the heat-fail temperatures of adhesive joints in shear tests were similar. The adhesive joint peel strength increased 1.2 times. The cardboard–HMAs based on virgin RXP adhesive joint peel tests exhibit adhesive failure, whereas the cardboard–HMAs containing grafted RXP joints show cohesive failure. [ABSTRACT FROM AUTHOR]

The biphasic catalytic epoxidation of cyclooctene using the ionic liquid (IL) 1,2‐dimethyl‐3‐octyl‐imidazolium perrhenate ([OMMIM]ReO4) as micellar catalyst and H2O2 as oxidant was investigated. Kinetic experiments were carried out in the intrinsic kinetic regime as proved by variation of stirring rate and temperature. Variation of catalyst concentration allowed for determination of the critical micellar concentration (CMC) of the catalytic IL. The effect of substrate concentrations on the reaction rate was also assessed. Based on the experiments, a kinetic model adapted from enzyme catalysis was proposed to account for the micellar reaction environment. The model takes into account the onset of micelle formation at the CMC. The application of the kinetic model illustrated the good agreement with the experimental data. The model will be applied to other micellar epoxidation reactions and for the design of an appropriate reaction setup in the future. Imidazolium perrhenate ionic liquids form micelles in aqueous H2O2 and thus act as micellar catalysts in epoxidation of cyclooctene. Key parameters such as the critical micelle concentration are determined from kinetic experiments in a batch reactor. The kinetic description is based on an adapted enzyme‐kinetic model, taking into account the micellar nature of the active species. [ABSTRACT FROM AUTHOR]

It was shown that the epoxidation of 1-octene by tert-butyl hydroperoxide in the presence of Mo2B is accompanied by the formation of an amorphous oxygen-containing phase on its surface. It was established that this is the phase that catalyzes the reaction and determines its speed and selectivity. [ABSTRACT FROM AUTHOR]

The cracking reactions of 1-octene over H-ZSM-5 zeolite are studied via micro-reactor and off-line spectroscopic techniques for up to 72 h on stream and a temperature range of 473–673 K. 1-Octene is found to react via a two-cycle hydrocarbon pool mechanism, with strong similarities to that reported for methanol-to-hydrocarbons chemistry. This dual-cycle mechanism requires temperatures of 673 K or higher to function with full efficiency, with lower temperatures deactivating portions of the cyclic mechanism, leading to premature deactivation of the catalyst through over-production of coke species. Inelastic neutron scattering is used to study the coke composition, identifying two distinct deactivation mechanisms depending on reaction temperature. The catalyst is also found to slowly progress from an aromatic-heavy to an olefin-heavy product regime even at full efficiency due to progressive blockage of active sites by amorphous carbon-rich coke. Artificial aging of the zeolite, through steam treatment, is found to shift the catalyst lifetime so that it commences at a later stage in this process, resulting in increased light olefin production. The reduced aromatic production also means that deactivation of the catalyst occurs more slowly in steamed catalysts than in fresh ones, after an equivalent time-on-stream. Collectively, these observations connect with the application of ZSM-5 catalysts to facilitate gasoline-to-olefins chemistry in fluidised catalytic cracking unit operations. [Display omitted] • 1-Octene is found to react via a two-cycle hydrocarbon pool mechanism. • The catalyst progresses from an aromatic-heavy to an olefin-heavy product regime. • Artificial aging of the zeolite by steam treatment, increases the catalyst lifetime. [ABSTRACT FROM AUTHOR]

Reactive molecular dynamics simulations were conducted to investigate the tribological behavior between two amorphous iron oxide substrates with octene molecules confined between them. The results revealed that higher temperatures facilitated the degradation and oxidation of octene molecules, leading to an increased quantity of reaction products such as water and oxidation products like alcohols. Due to the obstructive action of water molecules, the octene and its oxidation products were able to adsorb onto the substrate surfaces, resulting in the formation of a stably adsorbed carbon-based tribofilm at elevated temperatures. In addition, the water layer also significantly reduces friction by preventing direct contact between the carbon-based tribofilm, even though only a small amount of octene molecules are present at the interface. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Per- and polyfluoroalkyl substances (PFAS) are a diverse class of industrial chemicals with widespread environmental occurrence. Exposure to long-chain PFAS is associated with developmental toxicity, prompting their replacement with short-chain and fluoroether compounds. There is growing public concern over the safety of replacement PFAS. Objective: We aimed to group PFAS based on shared toxicity phenotypes. Methods: Zebrafish were developmentally exposed to 4,8-dioxa-3H-perfluorononanoate (ADONA), perfluoro-2- propoxypropanoic acid (GenX Free Acid), perfluoro-3,6-dioxa-4-methyl-7-octene-l-sulfonic acid (PFESA1), perfluorohexanesulfonic acid (PFHxS), perfluorohexanoic acid (PFHxA), perfluoro-n-octanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), or 0.4% dimethyl sulfoxide (DMSO) daily from 0-5 d post fertilization (dpf). At 6 dpf, developmental toxicity and developmental neurotoxicity assays were performed, and targeted analytical chemistry was used to measure media and tissue doses. To test whether aliphatic sulfonic acid PFAS cause the same toxicity phenotypes, perfluorobutanesulfonic acid (PFBS; 4-carbon), perfluoropentanesulfonic acid (PFPeS; 5-carbon), PFHxS (6-carbon), perfluoroheptanesulfonic acid (PFHpS; 7- carbon), and PFOS (8-carbon) were evaluated. Results: PFHxS or PFOS exposure caused failed swim bladder inflation, abnormal ventroflexion of the tail, and hyperactivity at nonteratogenic concentrations. Exposure to PFHxA resulted in a unique hyperactivity signature. ADONA, PFESA1, or PFOA exposure resulted in detectable levels of parent compound in larval tissue but yielded negative toxicity results. GenX was unstable in DMSO, but stable and negative for toxicity when diluted in deionized water. Exposure to PFPeS, PFHxS, PFHpS, or PFOS resulted in a shared toxicity phenotype characterized by body axis and swim bladder defects and hyperactivity. Conclusions: All emerging fluoroether PFAS tested were negative for evaluated outcomes. Two unique toxicity signatures were identified arising from structurally dissimilar PFAS. Among sulfonic acid aliphatic PFAS, chemical potencies were correlated with increasing carbon chain length for developmental neurotoxicity, but not developmental toxicity. This study identified relationships between chemical structures and in vivo phenotypes that may arise from shared mechanisms of PFAS toxicity. These data suggest that developmental neurotoxicity is an important end point to consider for this class of widely occurring environmental chemicals. https://doi.org/10.1289/EHP5843, Introduction Per- and polyfluoroalkyl substances (PFAS) are a structurally diverse class of industrial chemicals that contain aliphatic chains with all or some of the carbons bonded to fluorines (-CnF2n-) and [...]

The article deals with preparation, properties and usage of ethylene‐octene copolymers/clay films. Different properties of two types of ethylene‐octene copolymers (Engage 8540 and Engage 8842) with 17 and 45 wt% of octene (EOC‐17 and EOC‐45) were compared in nanocomposites with two types of clays—Cloisite 93A and Dellite 67. The aim was to evaluate the influence of (nano)filler type on ethylene‐octene nanocomposites properties. Mechanical and thermal properties, morphology, and UV radiation degradation were observed. Furthermore, permeability of three different gasses was determined. EOC nanocomposites perform a higher elongation at break, especially EOC‐45. Dynamic Mechanical Analysis (DMA) showed an increase of E′ modulus of all nanocomposites in a wide range of temperatures compared to pure EOC. Intercalation of nanofillers was studied by transmission electron microscopy (TEM) and X‐ray diffraction (XRD). It has been proved that EOC‐45 has a better dispersion EOC‐17. DSC analysis showed a shift in a crystallization temperature for EOC‐17, where the nanofiller acted as a nucleation agent due to the worse dispersion. Barrier properties were improved by almost 100% by addition of organoclay for all measured gasses; they were best for EOC‐17 nanocomposites due to a higher crystallinity. XRD together with transmission electron microscopy (TEM) showed much better dispersion for EOC‐45 nanocomposites. Fourier transform infrared spectroscopy (FTIR) and accelerated UV aging showed CO peaks for EOC nanocomposites. POLYM. COMPOS., 39:4581–4593, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Abstract Ethylene/1-olefin copolymers with a 1-olefin content >10 wt%, known as polyolefin plastomers (POP) and elastomers (POE), are materials of growing commercial importance. A relevant example are ethylene/1-octene (EO) copolymers. The thermal properties of nine 1-octene based POP/POE were studied by differential scanning calorimetry (DSC). The obtained thermograms were indicative of an asymmetric chemical composition distribution (CCD), triggering further investigations. At first, analytical temperature rising elution fractionation (a-TREF) was employed which gave further evidence of an asymmetric CCD for some samples. Given the low crystallinity of many of the samples, their CCD could, however, only be studied by high temperature high performance liquid chromatography (HT-HPLC). The hypothesis about an asymmetric CCD could be confirmed for all samples. The results were compared with theoretically calculated CCD (Stockmayer distributions) which are symmetrical. In a semiquantitative comparison, the main peak of the experimental CCD was found to be in good agreement with Stockmayer distributions. Graphical abstract Image Highlights • Chemical composition distribution studied by a-TREF, SGIC and TGIC. • Broad chemical composition distributions with characteristic shape found. • SGIC shows broader application range and higher resolution than TGIC. • Experimental results in good agreement with theory but clear differences revealed. [ABSTRACT FROM AUTHOR]