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1.
Aiqing Zhang Xiangdan Li Changwoon Nah Keejun Hwang Myong‐Hoon Lee 《Journal of polymer science. Part A, Polymer chemistry》2003,41(1):22-29
A soluble aromatic polyimide was chloromethylated via a reaction with chloromethyl methyl ether in the presence of tin(IV) chloride to produce a new starting material for the modification of aromatic polyimides. The chemical structure of the resulting polymer was confirmed by 1H NMR and Fourier transform infrared spectroscopy. The maximum number of chloromethyl groups per repeat unit was 1.81. The chloromethylated polyimide was stable up to 250 °C and soluble in both chloroform and tetrahydrofuran. So that its utilization for further modification could be demonstrated, cinnamic acid was reacted with the formed polyimide, and it produced a new photosensitive polyimide with a cinnamoyl side chain. The photosensitivity of the resulting polyimide was investigated with ultraviolet spectroscopic methods. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 22–29, 2003 相似文献
2.
以可溶性聚酰亚胺为反应底物,经氯甲基化反应制得氯甲基化聚酰亚胺,再以氯甲基为活性反应中心,在聚酰亚胺侧链上接枝聚丙二醇单丁醚(PPG),从而得到PPG侧链修饰聚酰亚胺.所制备的产物结构经红外光谱和核磁共振氢谱得以证实.介电常数及吸附脱附测试结果表明:经过大体积侧链PPG修饰后,聚合物的介电常数明显降低,由3.147降低至2.976;比体积和比表面积增大.同时,所制得的聚合物具有优良的溶解性能,在微电子工业中易于加工应用. 相似文献
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Huang Yingping Kun Yao Miaomiao Xiang Manke Jia Aiqing Zhang 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2019,93(6):1182-1191
Russian Journal of Physical Chemistry A - g-C3N4/BiOBr composites were obtained via solvothermal method. XRD, SEM, FTIR, UV–Vis DRS, BET, and BJH methods were used to characterize the... 相似文献
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将两种具有相似手性联萘空腔的手性卟啉1b和2b作为催化剂,对苯乙烯衍生物及非芳香烯烃底物进行了催化不对称环氧化反应。应用理论计算方法研究了底物同两种催化剂之间的作用机理;应用1H NMR探讨了催化剂的手性空腔结构;结果表明芳香烯烃同催化剂的手性联萘基团之间的p-p相互作用是决定该类催化剂对映选择性的重要因素,同时催化剂手性结构的立体位阻效应使该类催化剂具有良好的ee值。 相似文献
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A new approach to synthesize tolunitriles is reported. Tolunitriles can be prepared by selective ammoxidation of methylbenzyl
chlorides prepared by chloromethylation of toluene. The total yields can reach 83% and the selectivity of tolunitriles is
almost 100%. This approach provides a new path for preparing alkylbenzonitriles and other aromatic nitriles. 相似文献
9.
Synthesis of novel water‐soluble monotosylated ethylenediamines and their application in ruthenium and iridium‐catalyzed transfer hydrogenation of aldehydes are described. Various aldehydes, including electron‐deficient and electron‐rich variants, were reduced with high conversions and chemoselectivity using sodium formate as a hydrogen source in neat water. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
10.
1,5-Dinitroaryl-1,4-pentadien-3-ones were synthesized with ultrasound irradiation in the presence of K(2)CO(3) as catalyst. The reaction mechanism and the factors influencing the product were also discussed. The present procedure is more convenient with shorter reaction time and higher yields compared with conventional methods. 相似文献