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Biodegradable bi-functional cellulose derivatives were synthesized to remove widespread underground water cations such as; Ca 2+ , Mg 2+ , Fe 2+ , Pb 2+ , and Cu 2+ . Firstly, graft copolymerization of cellulose with binary monomers such as acrylic acid (AA), and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) with acrylamide (Am) were achieved using potassium persulfate as initiator. Then, cellulose/clay composites were prepared by graft copolymerization of cellulose using different montmorillonite concentrations such as 3, 6 and 9% weight/cellulose weight. The obtained Biodegradable grafted cellulose and their composites were used as adsorbents for the removal of Ca, Mg, Fe, Pb, and Cu ions individually from aqueous solutions. A possible reaction mechanism was deduced and the products were characterized by Fourier transfer infrared (FT-IR), scanning electron microscopy (SEM) and thermal degradation by thermogravimetric analysis (TGA). The results obtained from this study revealed that as the content of clay increases, the uptake of cations increasing and the removal order of the composites were Pb 2+  > Mg 2+  > Fe 2+  > Cu 2+  > Ca 2+ . The biodegradability of grafted cellulose was increased by the addition of clay. [ABSTRACT FROM AUTHOR]

Acrylic copolymers are useful in medical therapeutics. As in dental implants or intraocular lenses, acrylics are present in many medical devices or drug adjuvants. Industrial using of acrylics is still important in painting or textile manufacturing. Scientific research background has proved that acrylic suffer for depolymerized and cross-linking mechanisms under heating and photo-oxidative conditions. Those aging processes could lead to release of unreacted monomers and degradation products. We developed a new RP-HPLC method with good resolution, recovery, linearity, detection and quantification limits that is efficient for acrylic monomers quantification in in vitro and in vivo saline solution matrices. This method allows the detection of copolymer and medical devices degradation products too. Both the limit of quantification and the limit of detection for monomers and degradation products are above cytotoxic concentrations for human epithelial cells. Those biological results confirm the interest of the method for dosage of unreacted acrylics after polymerization and for the research of degradation products in body fluids as aqueous humor. [ABSTRACT FROM AUTHOR]

This paper describes a new method for the grafting of methacrylic acid (MAA) and other acrylic monomers onto wool fabric in aqueous medium. The novelty principally concerns the chemical approach of the redox grafting reaction that was carried out in the presence of sodium perborate (SPB) initiator. Before the grafting reaction was started, the wool fabric was treated first with a freshly prepared ferrous ammonium sulfate (FAS) solution. The so-treated fabric formed, with SPB, an efficacious redox system capable of initiating grafting of methacrylic acid (MAA) and other acrylic monomers onto the wool fabric. The effect of the polymerization conditions on the polymer criteria, namely, graft yield (%GY), homopolymer (%HP), total conversion (%TC), and grafting efficiency (%GE), was studied. These polymer criteria were found to depend spaciously upon concentrations of the Fe 2+ ion (activator), SPB (initiator), and MAA, pH of the polymerization medium, duration and temperature of polymerization. The graft copolymerization reaction has also been carried out in the presence of polymerization activators (e.g. reductant transition metal ions) and an inhibitor (e.g. hydroquinone). A suitable mechanism for the grafting processes has been suggested, in accordance with the experimental results. [ABSTRACT FROM AUTHOR]

An approach to modify the properties of UV curable polyurethane coatings by altering the amount and functionality of acrylic reactive diluents, in order to optimize the coating performance, is demonstrated. Based on the rheology analysis, a model of the rheological behavior of the UV curable materials depending on the amount and type of a reactive diluent in the composition is demonstrated in this study. The relationships between the rheological behavior, the mechanical properties and adhesion of the coatings prepared from polyurethane UV curable compositions containing different amounts and functionalities of acrylic reactive diluents, have been investigated and discussed in this study. Based on the results of the study, the desired properties of UV cured coatings can be modeled and controlled without changing the nature of a particularly selected oligomer, thus maintaining the advantages of its chemical structure in a coating composition. [ABSTRACT FROM AUTHOR]

Abstract: The goal of these studies was to measure and interpret the skin permeability characteristics of 2-hydroxypropyl acrylate (HPA) as a model compound that is completely miscible with water. Methods: In vitro permeation from HPA-H2O binary mixtures through human epidermis and silicone membranes was measured. Thermodynamic activities of HPA and H2O in these mixtures were determined. Permeation was also measured through epidermis and silicone from donor solutions with constant HPA activity but different H2O activities. Water uptake into desiccated human stratum corneum (SC) equilibrated with HPA-H2O mixtures was determined. Results: Steady-state flux of HPA through silicone was a linear function of HPA activity but not HPA concentration. For epidermis on the other hand, flux increased with HPA activity only for HPA activities ≤0.35. At constant HPA activity, flux decreased 4.5-fold as water activity decreased from 1 to 0.8. Incubation of SC with HPA-H2O mixtures resulted in substantial changes in SC water content, dependent on the water activity of the mixture and consistent with measured SC water sorption data. Conclusions: These experiments provide unequivocal evidence of a substantial increase in epidermal barrier function resulting from SC dehydration. Dehydration-related alterations in the SC appear responsible for the observed flux characteristics. [Copyright &y& Elsevier]

Cellulose nanocrystals (CNCs) show promise for enhancing properties of waterborne latexes and coatings. Miniemulsion polymerization is a promising route to obtaining well-controlled latex distributions sufficient to encapsulate CNCs in the monomer phase. Here, we demonstrate the first miniemulsion polymerization resulting in encapsulation of CNCs that incorporates costabilizer, water soluble initiator, and comonomer mixtures, aspects that are important for practical implementation. CNCs were added to the monomer phase as either unmodified (umCNC) or one of two functionalized forms: modified with isocyanatoethyl methacrylate (mCNC, containing a polymerizable vinyl group) or grafted with butyl acrylate/methyl methacrylate copolymer (gmCNC). The gmCNCs were incorporated successfully into acrylic particles. In contrast, the umCNCs were located outside the formed latex particles. Interestingly, the mCNCs coagulated during the polymerization, highlighting the challenge of utilizing polar and reactive acryloyl CNC surface modifiers that lead to migration from the droplet phase. [Display omitted] • Miniemulsion copolymerization is a flexible approach to prepare waterborne latex. • Cellulose nanocrystals (CNCs) were modified with an acrylic functionality. • CNCs were incorporated into latex particles for the first time by miniemulsion [ABSTRACT FROM AUTHOR]

Abstract: Acrylic monomers are a significant part of the global economy, contributing to the manufacture of over a billion tons of diverse polymeric consumer products every year. The development of more efficient, greener methods to manufacture this highly demanded class of compounds is an important goal in the realization of a sustainable chemical industry. The pursuit of environmentally benign production processes has inspired a rich body of industrial and academic research on methods for the catalytic hydration of nitriles, and this review surveys both established and newer methods of generating acrylic amides, acids, and esters from nitrile and cyanohydrin substrates. The review also examines synthetic and mechanistic studies of homogeneously catalyzed nitrile hydration reactions with an emphasis on explicating the parameters that impact catalyst performance. The final section is a discussion of catalyst properties, gleaned from the mechanistic studies, that will be useful in designing the next generation of nitrile hydration catalysts. [Copyright &y& Elsevier]

Abstract: A new styrene derivative monomer, 4-(N-carbazolyl)methyl styrene (CzMS), was synthesized by reacting 4-chloromethyl styrene with carbazole in the presence of sodium hydride. Then, CzMS was homopolymerized and copolymerized with different monomers such as methyl methacrylate (MMA), ethyl methacrylate (EMA), methyl acrylate (MA), ethyl acrylate (EA) and n-butyl acrylate (BA) by free radical polymerization method in N,N-di-methylformamide (DMF) solution at 70±1°C using azobisisobutyronitrile initiator to give the copolymers I–V in good yields. The structure of all the resulted polymers was characterized and confirmed by FT-IR, 1H NMR and 13C NMR spectroscopic techniques. The average molecular weight and glass transition temperature of polymers were determined using gel permeation chromatograph (GPC) and differential scanning calorimeter (DSC) instruments, respectively. It was found that these polymers with carbazole moieties have high thermal stability and the presence of bulk carbazole groups in polymer side chains leads to an increase in the rigidity and glass transition temperature of polymers. [Copyright &y& Elsevier]

Abstract: It has been theorized that, in order to get some positive interaction with the associative thickeners, the surfactants should have, at the end of the hydrophilic sequence, a short hydrophobic group. On the other hand, in order to control the hydrophilic lipophilic balance (HLB), it is wise to use well controlled polymerization procedures to build the block-copolymer. Then, the safer and simplest way to reach such goal is to use the ring-opening living anionic polymerization of butylene oxide (hydrophobic sequence) and then ethylene oxide (hydrophilic sequence); this living block-copolymer is then killed using an alkyl or aryl chloride (or bromide). However, because such surfactants include at the end of the hydrophilic sequence a hydrophobic group, they tend to adopt, when adsorbed onto hydrophobic latex particles, a back-folded conformation. In order to get for them an extended conformation, the hydrophilic sequence should have charges able to repel each other. This was achieved upon preparing block-copolymers of acrylic acid and butylacrylate, using a controlled radical polymerization with reversible addition fragmentation transfer (RAFT) agents, starting with the poly(acrylic acid) (PAA) sequence. Then, the radical fragment coming from the RAFT agent is at the end of the PAA sequence. A few rheological data actually confirm the interest of the concept. [Copyright &y& Elsevier]

Abstract: In the present work, a thermal-UV dual-cure process was performed on acrylate–oxetane systems. A 1:1 molar mixture of difunctional acrylate–oxetane mixture was prepared starting from 2,2-Bis(4-(3-acryloxy-2-hydroxypropoxy)phenyl)propane (BPADA) and 3-ethyl-3-{[(3-ethyloxetan-3-yl)methoxy]methyl}oxetane (OXT-221, DOX). Following a difunctional oxetane-acrylic monomer (OXAC) was synthesized. Starting from the 1:1 molar mixture a heterogeneous IPN is generated by dual cure process: the obtained material is characterized by DMTA curves with two maximum of tan δ peak; a broad damping effect can be expected. In the case of OXAC dual cured system a homogeneous material with no separation domain is obtained, as evidenced by a single tan δ peak in DMTA curves. [Copyright &y& Elsevier]

α-Methylene-γ-valerolactone (MeMBL) is an attractive, new, acrylic monomer that imparts high thermal stability to polymers. The absence of an economically attractive catalytic process for its preparation has prevented commercial development. Previous methods have used stoichiometric, expensive reagents. We now report a two-step process for its synthesis from a biomass-derived starting material, levulinic acid. The first step is a high yield hydrogenation of levulinic acid to γ-valerolactone (GVL) in nearly quantitative yield using a Ru/C catalyst. The second step is a heterogeneous, gas phase catalytic condensation of formaldehyde with GVL over basic catalysts, prepared from Group 1 and 2 metal salts on silica. While the reaction is very selective to lactone derivatives, the process suffers form rapid catalyst deactivation, however regeneration can be accomplished under relatively mild conditions. Although an isomer of the desired product is highly favored over a wide temperature range, proper choice of catalyst gives the thermodynamically unfavorable, yet desirable product in very high yield. [Copyright &y& Elsevier]

The new functional styrenic monomer, 4-trisylmethyl styrene (TsiMS) [Tsi=trisyl=tris(trimethylsilyl)methyl], was synthesized by reacting 4-chloromethyl styrene (CMS) with trisyllithium (TsiLi) in tetrahydrofuran (THF) solvent in the presence of copper chloride (CuCl). Attempt for the free radical polymerization of TsiMS by α,α′-azobis(isobutyronitrile) (AIBN) as an initiator at 70 ± 1 °C failed for several periods of times. This result showed that the trisyl group is a highly sterically hindered substituent and, subsequently, TsiMS becomes resistant for polymerization. Therefore, for preparation of new methacrylic, acrylic and dienic copolymers of TsiMS, we firstly synthesized the copolymers of CMS with different monomers such as methyl methacrylate (MMA), ethyl methacrylate (EMA), methyl acrylate (MA), ethyl acrylate (EA), n-butyl acrylate (BA) and isoprene (IP) by free radical polymerization method in toluene solution at 70 ± 1 °C using AIBN initiator to give the copolymers I–VI in good yields. The copolymer compositions were obtained using related 1H NMR spectra and the polydispersity indices of the copolymers determined using gel permeation chromatography (GPC). The trisyl groups were then covalently attached to the obtained copolymers as side chains by reaction between excess of TsiLi and benzyl chloride bonds of CMS units, to give the copolymers ITsi–VITsi in 80–92% yields. All the resulted polymers were characterized by FT-IR, 1H NMR and 13C NMR spectroscopic techniques. The solubility of all the copolymers was examined in various polar and non-polar solvents. The glass transition temperature (Tg) of all copolymers was determined by differential scanning calorimetry (DSC) apparatus. The Tg value of copolymers containing bulky trisyl groups was found to increase with incorporation of trisyl groups in polymer structures. The presence of trisyl groups in polymer side chains, create new macromolecules with novel modified properties. [Copyright &y& Elsevier]

The oxidation of ω-(ω-perfluoroalkylalkyl-sulfanyl)-alkyl acrylates to corresponding sulfoxides and sulfones is described in this paper. [Copyright &y& Elsevier]

Initiated chemical vapor deposition (iCVD) was used to deposit poly(hydroxypropyl methacrylate) (PHPMA) thin films from a reactive mixture of hydroxypropyl methacrylate and tert-butyl peroxide (TBPO) vapors. During iCVD, TBPO served as initiator, which allowed fast depositions on cooled substrate surfaces at low filament temperatures. In the presence of initiator, deposition rates up to 83.3 nm/min, were observed. In the studies performed at different substrate temperatures, a direct relation between the deposition rate and the substrate temperature was observed which indicated a surface-kinetics limited regime. Fourier-transform infrared and X-ray photoelectron spectroscopy analyses showed high structural retention of iCVD PHPMA. • Poly(hydroxypropylmethacrylate) (PHPMA) was synthesized by initiated chemical vapor deposition (iCVD). • There is a direct relation between substrate temperature and deposition rate. • iCVD of PHPMA is found to be surface-kinetics limited. • Very high deposition rate of 83.3 nm/min was achieved. [ABSTRACT FROM AUTHOR]