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通过4-溴苯甲醇和三甲基硅基乙炔的Sonagashira偶联反应与三甲基硅基的脱除反应,合成4-乙炔基苯甲醇.以4-乙炔基苯甲醇为引发剂,以有机氮杂环化合物DBU为催化剂,常温常压下进行丙交酯的活性开环聚合反应,采用1H-NMR和GPC对产物结构、分子量与分子量分布进行表征分析,结果表明,合成以了苯乙炔为端基的聚乳酸大分子单体PA-PLLA-3k、PA-PLLA-4k、PA-PDLA-3k和PA-PDLA-4k,实现了分子量的有效控制.以[Rh(nbd)Cl]2/Et3N为催化剂,实现了大分子单体的均聚,得到以聚乳酸为侧链的聚苯乙炔poly-(PA-PLLA)-3k,poly(PA-PLLA)-4k,poly(PA-PDLA)-3k和poly(PA-PDLA)-4k.采用GPC、GPC-MALLS和1H-NMR对聚苯乙炔进行表征分析,结果表明poly(PA-PLLA)和poly(PA-PDLA)均具有较高的分子量,分子链呈线形柔性链形态.CD和UV-Vis光谱分析表明poly(PA-PLLA)和poly(PA-PDLA)主链均形成了螺旋构象,而且Cotton效应的方向受大分子单体手性的影响,大分子单体的手性相同,聚苯乙炔主链Cotton效应的方向相同,大分子单体的手性相反,聚苯乙炔主链Cotton效应的方向相反;在不同溶剂中聚苯乙炔主链螺旋构象的规整程度不同;聚苯乙炔螺旋构象的稳定性随着温度的提高而降低.
The 4-ethynylbenzyl alcohol was synthesized by the Sonagashira coupling reaction of 4-bromobenzyl alcohol and trimethylsilylacetylene with the removal of trimethylsilyl.Using 4-ethynylbenzyl alcohol as initiator, The structure, molecular weight and molecular weight distribution of the products were characterized by 1H-NMR and GPC. The results showed that the synthesis of phenylacetylene as PA-PLLA-4k, PA-PDLA-3k and PA-PDLA-4k were successfully synthesized by using poly (L-lactic acid) (PA-PLLA) -3k, poly (PA-PLLA) -4k, poly (PA-PDLA) with polylactic acid as the side chain was synthesized by the copolymerization of acrylic acid with Et3N as catalyst. (PA-PLLA) and poly (PA-PDLA) -4k.The poly (phenylene vinylene) was characterized by GPC, GPC-MALLS and 1H- Molecular weight and molecular chain were linear flexible chain shape.CD and UV-Vis spectral analysis showed that the poly (PA-PLLA) and poly (PA-PDLA) backbone formed a spiral conformation, and Cotton effect direction by the macromonomer monomer Sexual effects , The chirality of the macromonomer is the same, the direction of the cotton effect of the polyphenylenevinylene backbone is the same, the chirality of the macromonomer is opposite, and the cotton effect of the polyphenylenevinylene main chain is opposite; in the different solvents, the polyphenylenevinylene backbone The degree of regularity of the helical conformation is different; the stability of the polyphenylacetylene helix conformation decreases with increasing temperature.