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21.
紫外光固化材料的技术和市场趋势 总被引:6,自引:0,他引:6
综述了紫外光固化材料在国内外市场的最新发展与应用,讨论了紫外光固化技术的几种新趋势。 相似文献
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A copolymerizable type II photoinitiator 4,4′-diacryloyloxybenzophenone (DABP) based on 4,4′-dihydroxybenzophenone (DHBP) and acryloyl chloride was synthesized, and its structure was confirmed by 1H NMR and real-time infrared spectroscopy. UV–vis absorption spectroscopy of DABP exhibited red-shifted maximal absorption as compared with benzophenone (BP). The kinetics of photopolymerization was studied by real-time infrared spectroscopy. It showed that DABP was a more effective photoinitiator than benzophenone. When this photointiator and amine was used to efficiently initiate polymerization of acrylates and methacrylates, both rate of polymerization and final conversion increased and the induction period was shortened with increase of amine concentration, DABP concentration and light intensity. 相似文献
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Poly(N-isopropylacrylamide) (NIPAAm) gels were formed by photopolymerization of NIPAAm in the absence of a crosslinker using a water solvent at 25°C. Factors affecting formation were the wavelength region of irradiated light, the type of photoinitiators, and the concentrations of the photoinitiator and monomer. A high-pressure mercury lamp (400 W) was used as a light source. An NIPAAm concentration of 10 wt % and irradiation time of 15 h was used for the photopolymerization. The gel (68% yield) was formed when the quartz glass system was used, but no gelation was observed for the Pyrex glass system that transmits light with π > 290 nm. The gel (100% yield) was easily formed, even in the latter system, when 30 mmol/L of hydrogen peroxide and potassium persulfate were used as the photoinitiator. Water soluble photoinitiators such as ferric chloride and sodium anthraquinone-2,7-disulfonate were not effective for the gel formation. Yield of the gel increased with increasing the potassium persulfate concentration (1–30 mmol/L), but it decreased when a high concentration of hydrogen peroxide (60 mmol/L) was used. The gel yield increased with the NIPAAm concentration (5–20 wt %). The degree of swelling of the resultant poly(NIPAAm) gels, which was measured by immersing the gels in water at various temperatures (0–50°C) for 24 h, steeply decreased at about 30°C with increasing temperature, exhibiting a temperature-responsive character. The gels swelled and shrank in water below and above the temperature, respectively. The extent of the character depended on the concentrations of hydrogen peroxide and monomer. The formation mechanism of the gel in the photopolymerization of NIPAAm using hydrogen peroxide photoinitiator was discussed. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:1313–1318, 1997 相似文献
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This paper describes the investigation of photoinitiated polymerization of poly(melamine-co -formaldehyde) acrylate (PMFA) by camphorquinone (CQ) and amines (AMH) by visible light (λ>400 nm). It was shown that as the concentration of CQ and/or AMH increases, the rate of polymerization reaches a maximum and then decreases. The double bond conversion of PMFA was 20–35%, whereas monomer conversion was 90–96%, depending on the polymerization conditions. Addition of inorganic filler up to 70 wt% did not significantly influence the polymerization kinetics. The final hardness of the photocured samples (with 70 wt% filler) was about half that found in a commercial dental restorative composite. The shrinkage of a composite with 70 wt% filler was 2.12%. Dental formulations based on photocuring of PFMA can be considered for clinical applications, after biological and toxicological evaluation. © 1999 Society of Chemical Industry 相似文献
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以邻巯基苯甲酸和异丙苯为原料,以一锅法合成光引发剂2-和4-异丙基-10-硫杂蒽酮异构体混合物。此混合物经IR、MS、^1HNMR和元素分析方法鉴定,并且探讨了反应时间、反应温度、配料比对反应的影响,得到最佳反应条件,提高了产率。 相似文献
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以α -卤代酮和二甲胺为原料 ,用常压法合成 1-对氟苯基 -2 -二甲氨基 -1-丁酮。探讨了合成反应的条件 ,当以α -溴代酮为原料 ,二甲胺 /α -溴代酮 (摩尔比 )为 4 / 1,在溶剂存在下 ,温度为 0± 2℃ ,反应 12h ,产率达92 5% ,并对产物的结构进行了表征 相似文献
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一种新型三芳基硫鎓盐光引发剂的合成 总被引:1,自引:0,他引:1
以二苯醚与等摩尔的对甲氧基苯甲酰氯为原料合成了4-甲氧基-4’-苯氧基二苯甲酮,4-甲氧基-4’-苯氧基二苯甲酮与二苯亚砜在P2O5和CH3SO3H介质中,80℃下反应24h,合成了一种新型的三芳基硫鎓盐,对这种新型三芳基硫鎓盐的结构用^1HNMR及^13C NMR进行了分析表征,并考察了它的光引发性能,发现它是一种很好的阳离子光引发剂。 相似文献
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