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以三氧六环为交联剂的COPNA树脂的合成与性能研究 总被引:4,自引:0,他引:4
以三氧六环为交联剂,萘、萘酚、蒽及其混合物为单体,可在对甲苯磺酸或三氯乙醚催化下,在80~160℃下反应得到未交联的缩合多核芳香烃树脂。对聚合反应机理作了一定的研究,并提出了聚合机理。以萘酚或萘为单体的树脂的交联较为困难,而在萘中加入蒽,不但可大大提高反应速率,也可使所得树脂的交联变得容易。交联后树脂在氮气中的热降解起始温度在400℃左右。 相似文献
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Radiation-initiated copolymerization of solid trioxane (TOX) with tetrahydrofuran (THF) was investigated. The effects of radiation dose, THF concentration, and post-polymerization temperature and duration on copolymer yield and THF incorporation were studied. These results are compared with the results of TOX homopolymerization under identical conditions. Copolymer yield was lower than that of homopolymer. Only a fraction of charged THF entered into the polymer chain. THF content and radiation dose also altered the MW of the copolymer but it showed better thermal stability. The initial reaction rates of the copolymerization were determined and from these the activation energy was found to be 36.2 kcal mol?1. 相似文献
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甲酸甲酯与三聚甲醛偶联合成乙醇酸甲酯 Ⅱ.硫酸/金属羰基化合物对收率的影响 总被引:1,自引:0,他引:1
研究了硫酸/金属羰基化合物对甲酸甲酯与三聚甲醛偶联合成乙醇酸甲酯反应的催化作用,结果乙醇酸甲酯和甲氧基乙酸甲酯的收率均有提高;用甲醇分解偶联反应母液,进一步提高了产品收率,优选出较佳的配比,用10ml硫酸、3.12gAg2SO4(I)所形成的硫酸/金属羰基化合物作催化剂,与45ml甲酸甲酯和12g三聚甲醛进行偶联反应,在甲醇分解偶联反应母液后,得到乙醇酸甲酯和甲氧基乙酸甲酯的摩收率分别为59.82%和34.39%,超过国外研究结果。 相似文献
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三聚甲醛和环氧乙烷的本体共聚 总被引:3,自引:2,他引:1
研究了三聚甲醛与环氧乙烷的本体共聚,讨论了共单体环氧乙烷的用量、催化剂用量、聚合时间及聚合温度对共聚甲醛的收率及产物热稳定部分的影响;同时比较了共单体环氧乙烷和二氧五环对共聚的效果。结果表明,成本较低的环氧乙烷与三聚甲醛的共聚产物,其热碱稳定部分较高、分子量也较大。因此这一条共聚路线是较有利的工艺路线。 相似文献
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Copolymers (polyoxymethylene) were prepared by cationic copolymerization of 1,3,5‐trioxane (TOX) with 1,3‐dioxolane (DOX) in the presence of Maghnite‐H+ (Mag‐H+) in solution. Maghnite is a Montmorillonite sheet silicate clay, with exchanged protons to produce Mag‐H+. Various techniques, including 1H‐NMR, 13C‐NMR, FT‐IR spectroscopy, and Ubbelohde viscometer were used to elucidate structural characteristics properties of the resulting copolymers. The influence of the amount of catalyst, of dioxolane (DOX), temperature, solvent, and time of copolymerization on yield and on intrinsic viscosity of copolymers was studied. The yield of copolymerization depends on the amount of Mag‐H+ used and the reaction time. We also propose mechanisms involved in the synthesis of copolymer (polyoxymethylene). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
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