共查询到20条相似文献,搜索用时 78 毫秒
1.
本文总结了将乙炔基、乙烯基、丙烯基、氨基、马来欧亚胺基、氰酸酯基、环氧基等活性基团引入聚芳醚砜链端的方法。引用参考文献27篇。 相似文献
2.
本文总结了将乙炔基、乙烯基、丙烯基、氨基、马来酰亚胺基、氰酸酯基、环氧基等活性基团引入聚芳醚砜链端的方法。引用参考文献27篇。 相似文献
3.
含环氧端基酚酞聚芳醚腈的合成及表征 总被引:1,自引:0,他引:1
环氧树脂(ER)的冲击韧性和耐开裂性较差,因此,提高其抗冲强度而不显著影响力学性能和耐热性能是重要的研究课题.对于ER的增韧,以前主要采用液态橡胶.近年来,人们开始研究使用高性能热塑性树脂增韧ER[1~3].聚醚腈(PCE)是目前机械强度最高的热塑性... 相似文献
4.
5.
6.
7.
8.
本文系统研究了全氟己基乙基甲基丙烯酸酯(C6氟酯)的催化调聚体系及阻聚体系的反应条件。在催化调聚体系中,当催化剂为复合催化剂铜粉+4-甲基吡啶,反应温度介于120~130℃,四氟乙烯与五氟碘乙烷的摩尔比为1:4时,产物中6碳原子的氟碳链含量多、分子量分布窄、调聚转化率高。在阻聚体系中,复合阻聚剂ZJ-701+MQ的阻聚效果最好。当复合阻聚剂ZJ-701与MQ质量比为1:3,浓度为350 mg·kg-1时,C6氟酯的转换率最小,阻聚效果也最好。对催化调聚体系和阻聚体系反应条件的优化,显著提高C6氟酯的产率,降低了原材料的消耗成本。该工艺路线易操控、成本低廉且转化率高,有利于工业生产。 相似文献
9.
含环氧基聚二甲基硅氧烷及其硫化过程的分子运动 总被引:2,自引:0,他引:2
采用扭辩分析法详细研究了含环氧基聚二甲基硅氧烷在110-230K范围内的的分子运动情况,讨论了氧基团对聚二甲基硅氧烷主链的玻璃化转变温度,次级转变温度、烷融温度及粘流浊国度等动态力学性能的影响。 相似文献
10.
11.
SynthesisandPropertiesof Aryloxy-terminatedPolydimethylsiloxanesLinGuoliang;JiangZhiyuang;HongManshui(CollegeofChemistryandCh... 相似文献
12.
N. A. Belov A. N. Tarasenkov N. A. Tebeneva N. G. Vasilenko G. A. Shandryuk Yu. P. Yampolskii A. M. Muzafarov 《Polymer Science Series B》2018,60(3):405-413
Novel membrane materials—three-dimensional polydimethylsiloxane networks with nonaggregated metal atoms (Fe, Zr)—have been synthesized using commercial siloxane rubber SKTN and polyfunctional metallosiloxane as a crosslinking agent. For the resulting composites, the permeability, diffusion, and solubility coefficients for a wide range of gases have been determined. It has been found that the permeability coefficients for most of the gases are close to values previously obtained for linear siloxanes; however, the permeability and Р(С4Н10)/Р(СН4) selectivity for n-butane are significantly higher. It has been shown that the differences in the permeability coefficients are attributed to higher solubility coefficients of gases in the synthesized composites. 相似文献
13.
V. V. Gorodov P. A. Tikhonov M. I. Buzin V. G. Vasil’ev S. A. Milenin D. I. Shragin V. S. Papkov A. M. Muzafarov 《Polymer Science Series B》2018,60(3):290-298
4-(Dimethylvinylsilyl)benzoic acid is obtained by organolithium synthesis. Polydimethylsiloxanes containing silicon hydride groups are modified by introducing benzoic acid fragments via the hydrosilylation reaction. The thermal and rheological properties of the copolymers formed are studied. It is found that a rise in the content of benzoic acid results in a shift in the glass-transition temperature to a higher temperature region and the copolymers do not crystallize. Benzoic acid fragments improve the intermolecular interaction of polydimethylsiloxane chains more strongly than the ones of undecenoic acid. 相似文献
14.
Yun Yan GAO Chang Jiang YOU Jin Ping CHEN Yong Yong LIU Bao Wen ZHANG Yi LI* Technical Institute of Physics Chemistry Chinese Academy of Sciences Beijing 《中国化学快报》2002,13(12)
The photochemistry of the vitamin D family and their precursors has been the subject of extensive studies for many years1-4. Most of the studies focus on the photoisomer- ization of 7-dehydrocholesterol and that of tachysterol to previtamin D3, which is of commercial importance in the synthesis of vitamin D34, 5. Recently the cis/trans isomerization of vitamin D analogs (Scheme 1) draws attention because of its importance in the synthesis of hydroxylated vitamin D metabolites6. However, o… 相似文献
15.
报道了 732树脂固载三氯化铁催化合成苯酚 ,研究了反应温度、双氧水浓度、反应物投料比、反应时间和催化剂用量对反应的影响及催化剂的重复使用性能。 相似文献
16.
Yong Bin HAN Jin Ping CHEN Bai Ning LIU Guo Qiang YANG Yi LI 《中国化学快报》2006,17(2):159-162
1α-Hydroxyvitamin D3 1 (1α-hydroxycholecalciferol) is a biologically active form ofvitamin D3 2 which exhibits a much broader spectrum of biological activities thanvitamin D3 . 1,2 Recently a number of analogues have been found to have specificenhanceme… 相似文献
17.
Fe-MSU-1介孔分子筛的合成及其催化苯酚羟基化性能 总被引:1,自引:0,他引:1
以月桂醇聚氧乙烯醚为模板剂,在中性条件下成功合成了Fe-MSU-1介孔分子筛.采用X射线衍射、傅里叶变换红外光谱、紫外-可见吸收光谱、电子自旋共振谱、透射电镜、低温N2吸附和电感耦合等离子体原子发射光谱对样品进行了表征.考察了Fe-MSU-1分子筛在苯酚羟基化反应中的催化性能以及工艺条件对苯酚羟基化反应的影响.结果表明,Fe3 离子进入了分子筛骨架,Fe-MSU-1分子筛具有均一的蠕虫状介孔结构,平均孔径约为2.9nm.在焙烧后的Fe-MSU-1样品中,Fe3 主要以四配位的形式存在,无骨架外Fe2O3物种形成.以水为溶剂,在苯酚/H2O2摩尔比为3,反应温度353K,反应时间7h的条件下,苯酚和H2O2的转化率以及苯二酚的选择性分别达到20.4%,96.9%和99.6%. 相似文献
18.
19.