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The paper describes the synthesis of N-2/4-toluyl methacrylatoethyl carbamates using 2/4-toluyl isocyanate and 2-hydroxyethyl methacrylate. Homopolymerisation and copolymerisation of these novel monomers with methyl methacrylate was carried out using benzoyl peroxide as an initiator and tetrahydrofuran as solvent. Photopolymerisation of N-4-toluyl methacrylatoethyl carbamate could be carried out without the use of photosensitiser. Structural characterisation of copolymers was done using 1H-NMR. Thermal stability of copolymers was evaluated in a nitrogen atmosphere by dynamic thermogravimetry. 相似文献
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Hamid Javaherian Naghash Ahmad Reza Momeni Hamid Alian Ahmad Reza Massah Shahla Ataie 《Polymer International》2005,54(11):1564-1571
Poly(methyl methacrylate) (PMMA) gels with varying amounts of silicone and solvent and constant amounts of crosslinker were prepared by solution free radical crosslinking copolymerization of methyl methacrylate (MMA), ethylene glycol dimethacrylate (EGDM), tetraethoxysilane (TEOS) and vinyltriethoxysilane (VTES) comonomer systems. They were then studied in benzene at a total monomer concentration of 3.5 mol L?1 and 70 °C. The conversion of monomer, volume swelling ratio, weight fraction and gel point were measured as a function of the reaction time, silicone concentration and benzene content up to the onset of macrogelation. Structural characteristics of the gels were examined by using equilibrium swelling in benzene, gel fraction and Fourier‐transform infrared (FTIR) analysis. The morphology of the copolymers was also investigated by SEM. Based on the obtained results, it was concluded that the FTIR data did not have the capacity to show the presence of the VTES or TEOS moiety in these kinds of copolymers. On the other hand, the variation of weight fraction of gel, Wg, and its equilibrium volume swelling ratio in benzene, qv, exhibited the same behaviour as that of MMA/EGDM copolymers. Also, the dilution of the monomer mixture resulted in an increase in the gel point and swelling degree and a decrease in the percent of conversion and gel fraction. Finally, TEOS is not an ideal silicone compound for reaction in the MMA/EGDM copolymerization system, whereas VTES is a suitable silicone comonomer for this system and it has been proved useful. Copyright © 2005 Society of Chemical Industry 相似文献
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Copolymers of 2-hydroxy ethyl methacrylate-2-vinyl pyridine (H/V) of different composition were synthesized by free radical bulk polymerization using azobisisobutyronitrile (AIBN) as an initiator under nitrogen atmosphere. The copolymer compositions were calculated from 1H NMR spectra. The reactivity ratios for H/V copolymers obtained from a linear Kelen-Tudos method (KT) and nonlinear error-in-variables method (EVM) are rH = 0.50 ± 0.10, rV = 1.04 ± 0.08 and rH = 0.55, rV = 1.06 respectively. The complete spectral assignment of methine, methylene, methyl, carbonyl, and aromatic carbon regions in term of compositional and configurational sequences of H/V copolymers were done with the help of 13C{1H} NMR, distortionless enhancement by polarization transfer (DEPT), two-dimensional heteronuclear single quantum coherence (HSQC) along with total correlated spectroscopy (TOCSY). © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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报道以甲基丙烯酸羟乙酯与甲基丙烯酸甲酯的共聚物为载体膜材料,研制成非酶标记的T4免疫传感器,并对载体膜材料的共聚方法及共聚物共聚比与传感器灵敏度的关系进行了探讨。 相似文献
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MCS接枝共聚物的结构和形态 总被引:4,自引:0,他引:4
将甲基丙烯酸甲酯(MMA)、苯乙烯(S)在氯化聚乙烯(CPE)存在下进行悬浮接枝共聚,获得MCS树脂。本文着重考察了MCS树脂的化学结构及胶粒形态。结果表明,确实发生了接枝共聚。CPE用量、RSH含量、引发剂浓度、反应温度、溶胀时间及聚合转化率对MCS树脂的接枝率、接枝效率均有影响。MCS树脂是接枝共聚物、MMA/S共聚物与MMA均聚物的混合物,橡胶相CPE在MCS树脂中的分散情况为“海岛结构”, 相似文献
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