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Acrylate Monomers (acrylate + monomer)
Selected AbstractsWell-defined amphiphilic graft copolymer consisting of hydrophilic poly(acrylic acid) backbone and hydrophobic poly(vinyl acetate) side chainsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 22 2009Yaogong Li Abstract A series of well-defined amphiphilic graft copolymers containing hydrophilic poly(acrylic acid) (PAA) backbone and hydrophobic poly(vinyl acetate) (PVAc) side chains were synthesized via sequential reversible addition-fragmentation chain transfer (RAFT) polymerization followed by selective hydrolysis of poly(tert -butyl acrylate) backbone. A new Br-containing acrylate monomer, tert -butyl 2-((2-bromopropanoyloxy)methyl) acrylate, was first prepared, which can be polymerized via RAFT in a controlled way to obtain a well-defined homopolymer with narrow molecular weight distribution (Mw/Mn = 1.08). This homopolymer was transformed into xanthate-functionalized macromolecular chain transfer agent by reacting with o -ethyl xanthic acid potassium salt. Grafting-from strategy was employed to synthesize PtBA- g -PVAc well-defined graft copolymers with narrow molecular weight distributions (Mw/Mn < 1.40) via RAFT of vinyl acetate using macromolecular chain transfer agent. The final PAA- g -PVAc amphiphilic graft copolymers were obtained by selective acidic hydrolysis of PtBA backbone in acidic environment without affecting the side chains. The critical micelle concentrations in aqueous media were determined by fluorescence probe technique. The micelle morphologies were found to be spheres. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6032,6043, 2009 [source] Organosoluble star polymers from a cyclodextrin coreJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 21 2005Khaled Karaky Abstract Well-defined star polymers were synthesized with a combination of the core-first method and atom transfer radical polymerization. The control of the architecture of the macroinitiator based on ,-cyclodextrin bearing functional bromide groups was determined by 13C NMR, fast atom bombardment mass spectrometry, and elemental analysis. In a second step, the polymerization of the tert -butyl acrylate monomer was optimized to avoid a star,star coupling reaction and allowed the synthesis of a well-defined organosoluble polymer star. The determination of the macromolecular dimensions of these new star polymers by size exclusion chromatography/light scattering was in agreement with the structure of armed star polymers in a large range of predicted molecular weights. This article describes a new approach to polyelectrolyte star polymers by postmodification of poly(tert -butyl acrylate) by acrylic arm hydrolysis in a water-soluble system. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5186,5194, 2005 [source] Effects of hydrophilic monomer types on poly(styrene-acrylate)/montmorillonite nanocomposites made by in-site emulsion polymerization,POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 6 2009Fa-Ai Zhang Abstract Organic modified montmorillonite (OMMT) was made of pristine montmorillonite (MMT) treated with cetyl trimethylammonium bromide (CTAB). Two kinds of nanocomposites, poly(styrene-acrylate)/MMT (P(S-A)/MMT) and poly (styrene-acrylate)/OMMT (P(S-A)/OMMT) were prepared from styrene (St), hydrophilic acrylate monomer, and MMT (or OMMT) by in-site emulsion polymerization. Effects of different monomers, , -hydroxyethyl methacrylate (HEMA), acrylic acid (AA), methacryclic acid (MAA) on the thermal stability of the two nanocomposites were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TG). The structures of the nanocomposites were characterized by infrared spectroscopy (IR) and X-ray diffraction (XRD). The morphology of the nanocomposite was observed by transmission electron microscope (TEM). The results showed that the thermal stabilities of the two composites were enhanced by the addition of HEMA, AA, or MAA. The P(S-A)/OMMT nanocomposite showed higher thermal stability than that of the P(S-A)/MMT nanocomposite. In particular, HEMA improved the thermal stability of the P(S-A)/OMMT nanocomposite, which is more efficient than methacrylic acid (MA) and AA. Copyright © 2009 John Wiley & Sons, Ltd. [source] Perfluorocyclobutyl-containing Amphiphilic Block Copolymers Synthesized by RAFT PolymerizationCHINESE JOURNAL OF CHEMISTRY, Issue 11 2009Yongjun Chen Abstract Amphiphilic block copolymers containing hydrophobic perfluorocyclobutyl-based (PFCB) polyacrylate and hydrophilic poly(ethylene glycol) (PEG) segments were prepared via reversible addition-fragmentation chain transfer (RAFT) polymerization. The PFCB-containing acrylate monomer, p -(2-(p -tolyloxy)perfluorocyclobutoxy)-phenyl acrylate, was first synthesized from commercially available compounds in good yields, and this kind of acrylate monomer can be homopolymerized by free radical polymerization or RAFT polymerization. Kinetic study showed the 2,2,-azobis(isobutyronitrile) (AIBN) initiated and cumyl dithiobenzoate (CDB) mediated RAFT polymerization was in a living fashion, as suggested by the fact that the number-average molecular weights (Mn) increased linearly with the conversions of the monomer, while the polydispersity indices kept less than 1.10. The block polymers with narrow molecular weight distributions (Mw/Mn,1.21) were prepared through RAFT polymerization using PEG monomethyl ether capped with 4-cyanopentanoic acid dithiobenzoate end group as the macro chain transfer agent (mPEG-CTA). The length of the hydrophobic segment can be tuned by the feed ratio of the PFCB-based acrylate monomer and the extending of the polymerization time. The micellization behavior of the block copolymers in aqueous media was investigated by the fluorescence probe technique. [source] Studies on synthesis and characterization of a novel acrylic aromatic amide oligomer of aminolysed endproducts generated from pet waste with hydrazine monohydrate and its photocuring with acrylate monomersJOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2010R. K. Soni Abstract A novel acrylic aromatic amide oligomer was synthesized by using depolymerized end product of PET waste with hydrazine monohydrate. The end product of aminolysed PET waste was synthesized under ambient conditions and was used in the preparation of novel acrylic oligomer with the reaction of acryloyl chloride prepared from acrylic acid. The acrylic oligomer was characterized by spectroscopic techniques, such as FTIR, 1H-NMR, UV, Mass spectrometry, and by other analytical techniques such as, Iodine value, TGA, and DSC. The proposed structure of the oligomer is supported by its spectral analysis and the same is inferred from other techniques. The acrylic oligomer mixed with other acrylate monomers such as methylmethacrylate, ethylhexylacrylate, acrylic acid, and photoinitiator, can be cured by UV radiation and can thus be used as an adhesion promoter on metal/glass surface. This article presents the possibility of using a difunctional aromatic amide oligomer with excellent hydrogen bonding capacity as an alternative to urethane acrylates in radiation curable formulations. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Direct measurements of the addition and recombination of acrylate radicals: Access to propagation and termination rate constants?JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 11 2006J. Lalevée Abstract Acrylate radicals produced by the addition of an aminoalkyl radical to five acrylate monomers were directly observed by transient absorption spectroscopy, which allowed us to easily follow their chemical reactivity. It was possible (1) to characterize their absorption in the visible part of the spectrum, (2) to calculate their absorption properties, (3) to determine the energy barriers of the addition through quantum mechanical calculations, (4) to monitor the kinetics of the subsequent addition to another monomer unit, and (5) to follow the recombination of two acrylate radicals. These two latter points could mimic the propagation and termination reactions of polymerization-propagating acrylate radicals. Methacrylate and acrylonitrile radicals were also studied. The obtained results were in good agreement with the propagation rate constants determined by the well-established pulsed laser polymerization techniques. Our method could likely provide rapid access to both the propagation and termination rate constants in suitable systems and appears to be powerful and promising for studying and comparing the reactivities of different acrylate monomer structures. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3577,3587, 2006 [source] Synthesis of telechelic oligomers by atom transfer radical polymerization: A study of acrylate monomersJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 11 2005Belkacem Otazaghine Abstract Different acrylate oligomers were synthesized by atom transfer radical polymerization in the presence of a transfer agent and CuBr/1,1,4,7,10,10-hexamethyltriethylenetetramine. The functionality in bromine was determined by 1H NMR. These oligomers were coupled in the presence of Cu(0) and the ligand 2,2,-bipyridine. The coupling yield was determined by size exclusion chromatography and NMR analysis and depended on the nature of the monomer and not on the molecular weight. In other words, the preliminary functionalization of the brominated chain end with styrene increased the coupling yield. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2377-2394, 2005 [source] Burning mouth syndrome: the role of contact hypersensitivityORAL DISEASES, Issue 4 2009R Marino Background:, Burning mouth syndrome is a burning sensation or stinging disorder affecting the oral mucosa in the absence of any clinical signs or mucosal lesions. Some studies have suggested that burning mouth syndrome could be caused by the metals used in dental prostheses, as well as by acrylate monomers, additives and flavouring agents, although others have not found any aetiologic role for hypersensitivity to dental materials. Objective:, To evaluate the extent and severity of adverse reactions to dental materials in a group of patients with burning mouth syndrome, and investigate the possible role of contact allergy in its pathogenesis. Materials and methods:, We prospectively studied 124 consecutive patients with burning mouth syndrome (108 males; mean age 57 years, range 41,83), all of whom underwent allergen patch testing between 2004 and 2007. Results:, Sixteen patients (13%) showed positive patch test reactions and were classified as having burning mouth syndrome type 3 or secondary burning mouth syndrome (Lamey's and Scala's classifications). Conclusion:, Although we did not find any significant association between the patients and positive patch test reactions, it would be advisable to include hypersensitivity to dental components when evaluating patients experiencing intermittent oral burning without any clinical signs. [source] Short wavelength light reflecting films from side-chain liquid crystal homopolymers with chiral spacersPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 9 2001J. M. G. Cowie Abstract A series of acrylate monomers with alkoxy tails of varying lengths are synthesised and polymerised. The butoxy analogue had a stable enantiotropic cholesteric liquid crystalline phase which formed a grandjean texture when prepared as a thin film between glass slides. The polymer was mixed with a low molar mass nematic liquid crystal in various proportions and the pitch of the chiral nematic phases were determined using a cano-wedge cell technique. The polymer prepared from (S)-2-(4-butoxyphenyl-4,-benzoyloxy)-1-methyl ethyl acrylate had a pitch length of 113,nm which indicates that the polymer film could be employed in optical devices requiring selective reflection of light with short wavelengths in the region of 170,nm. Copyright © 2001 John Wiley & Sons, Ltd. [source] | ||||||||||