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41.
UV curable epoxy acrylates were reinforced with two different organically modified montmorillonites (MMTs) and an unmodified MMT. Conversion and rate of polymerization was monitored by real time infrared spectroscopy (RTIR) and photo-DSC. Microstructures were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and optical clarity. Optical clarity of the films containing clay was quite good as only a slight decrease was observed. Physical properties of the reinforced films were examined by differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), hardness and tensile testing. Enhancements in glass transition temperature (Tg), thermal stability and mechanical properties were observed. The films reinforced with the unmodified MMT exhibit the most significant enhancements in properties. 相似文献
42.
Copolymers of -methyl styrene and 2-ethylhexyl acrylate were prepared in a benzene solution. The presence of the copolymers were confirmed by solubility, IR and NMR tests. The molecular weight and the polydispersity of the polymers were estimated by GPC. The copolymers obtained were blended with paraffinic and naphthenic base oils. The viscosity, the viscosity index (VI) the Q value as well as the stability to shear and oxidation were obtained for these blends. The results are compared with the results obtained with an oil blend containing a commonly used high temperature additive. Two of the copolymers obtained have shown to be good alternatives for specific applications.Presented at the Symposium, 76th CSC Congress, Sherbrooke, Quebec, May 30–June 3, 1993, honoring Professor Donald Patterson on the occasion of his 65th birthday. 相似文献
43.
The microstructure of a series of high conversion copolymers of methyl acrylate (MA) and N-vinylcarbazole (NVC) was characterized by NMR. 1H- and 13C-NMR spectra were assigned by comparison to the homopolymers and by using heteronuclear shift correlation spectroscopy. MA-centered triad distributions were obtained from the carbonyl carbon. Distributions of NVC sequences were determined from aromatic carbons 1 and 8a, and aromatic proton 1 These experimentally determined sequence distributions were compared to those calculated from reactivity ratios approximated from the copolymer compositions. Agreement was very good for low NVC content copolymers. Three signals were particularly useful in providing rapid assessment of the distribution of NVC units within low NVC content copolymers: proton 1 and carbon 1 of NVC and the carbonyl carbon of MA. © 1992 John Wiley & Sons, Inc. 相似文献
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规整链球型含C_(60)聚(丙烯酸β-羟乙酯)的合成及其在水中的自组装 总被引:2,自引:0,他引:2
C60 由于其独特的物理化学性质 ,在生命科学中引起了人们的广泛兴趣 .例如 :水溶性C60 的羧酸衍生物 ,羟基取代C60 ,C60 的氨基酸水溶性衍生的合成已有报道[1~ 3] ,并被用来研究C60 的生物化学及医学活性 .Tokuyama[4 ] 等合成了酶功能化C60及与核酸连接的C60 ,研究并证明了它的细胞毒性及G 选择DNA切割能力等生化活性 .Friedman[5]等合成了水溶性C60 的羧酸衍生物 ,研究了它对HIV 1艾滋病毒的抑制作用 ,此外 ,关于不同C60含量的C60 蛋白质衍生物的合成及性质的研究也有报道[6] .C60 是一个直径为 0 71… 相似文献
46.
The influences of UV light irradiation (313 nm) and diffused daylight on the polymerization of methyl acrylate initiated by the ceric ammonium nitrate without any reducing agent have been studied both in aqueous nitric acid and in pure water. The rate of polymerization was found to be accelerated and the overall activation energy and the induction time were found to be decreased sharply by the UV light irradiation. Under UV light, the rate of polymerization is 8 times as high as the rate in dark. The rate of polymerization was found to attain a maximum with the increase of nitric acid concentration and the rate of polymerization became less sensitive to UV light in the presence of nitric acid whereas the induction period reduced outstandingly. Based on the experimental results, the mechanism is proposed. 相似文献
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合成了丙烯酸三苯基锡酯及其聚合物,通过IR、 ̄1HNMR、 ̄(13)CNMR对其结构进行了表征,推断单体中的锡原子与羰基氧原子间存在分子间的配键,锡原子的配位数是5,而聚合物没有形成锡氧配键。 相似文献
49.
硅基交联聚酸正丁酯反相HPLC固定相的研究 总被引:2,自引:0,他引:2
采用硅胶表面直接交联聚合法,制备了硅基交联聚丙烯酸正丁酯反相高效液相色谱固定相。用红外、扫描电镜和元素分析等方法对固定对进行了表征。考察了固定相对含氧芳烃衍生物的分离。 相似文献
50.