Synthesis of aliphatic polyesters by a chain‐extending reaction with octamethylcyclotetrasilazane and hexaphenylcyclotrisilazane as chain extenders
Synthesis of aliphatic polyesters by a chain‐extending reaction with octamethylcyclotetrasilazane and hexaphenylcyclotrisilazane as chain extenders
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DOI：
10.1002/app.20330
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发表时间：
2004-06
影响因子：
3
通讯作者：
Jing‐bo Zhao;Xiao-Feng Wu;Wantai Yang
中科院分区：
文献类型：
--
作者：
Jing‐bo Zhao;Xiao-Feng Wu;Wantai Yang
以己二酸或丁二酸为原料，与过量的二甘醇、乙二醇或丁二醇缩聚，合成了聚己二醇己二酸酯(PDEGA)、聚己二酸乙二醇酯(PEA)和聚丁二酸丁二醇酯(PBS)等脂肪族端基聚酯，其相对分子质量为1247~1948年。以八甲基环四硅氮烷(OMCT)或六苯基环三硅氮烷(HPCT)为扩链剂，通过扩链反应合成了高相对分子质量的聚酯。凝胶渗透色谱(GPC)表征表明，扩链PDEGA的分子量为12,644~32,870，分子量为22,786~70,048；扩链PEA的分子量为11,368，分子量为19,877；扩链PBS的分子量为9823~39,873，分子量为18,823~137,192。对扩链聚酯进行了核磁共振氢谱、红外光谱和差示扫描量热谱的表征。扩链聚乙二醇乙二醇酯的1H-核磁共振谱中7.37ppm和7.67ppm处的多个峰以及扩链PbS的红外光谱中3051.1和1593.4 cm−-1处的多个峰证明了扩链反应得到的聚酯中的SiPh2结构。DSC研究表明，扩链反应引入的SiPh2基团降低了聚酯链的规整性，从而使扩链PBS和PEA的熔点较原来的HO端基PBS和PEA有所降低。©2004威利期刊公司应用波利姆科学杂志92：3333-3337,2004
Aliphatic HO-terminated polyesters such as poly(diethylene glycol adipate) (PDEGA), poly(ethylene adipate) (PEA), and poly(butylene succinate) (PBS) with molecular weight from 1247 to 1948 were synthesized through condensation polymerization from adipic acid or butanedioic acid with excess diethylene glycol, ethylene glycol, or butylene glycol. From the HO-terminated polyesters, polyesters with high molecular weight were synthesized by a chain-extending reaction with octamethylcyclotetrasilazane (OMCT) or hexaphenylcyclotrisilazane (HPCT) as chain-extenders. Gel permeation chromatography (GPC) characterization shows that the Mn of chain-extended PDEGA is from 12,644 to 32,870, Mw is from 22,786 to 70,048; Mn of chain-extended PEA is 11,368, Mw is 19,877; and the Mn of chain-extended PBS is from 9823 to 39,873, Mw is from 18,823 to 137,192. The chain-extended polyesters were also characterized by 1H-NMR spectrum, IR spectra, and DSC spectra. The multiple peaks at 7.37 and 7.67 ppm in the 1H-NMR spectrum of chain-extended PDEGA and peaks at 3051.1 and 1593.4 cm−1 in the IR spectrum of the chain-extended PBS show the evidence of the SiPh2 structure in the polyesters obtained from the chain-extending reaction. DSC study shows that the bulky SiPh2 units introduced by the chain-extending reaction lower the regularity of the polyester chains, so the melting point of the chain-extended PBS and PEA decreases compared to that of the original HO-terminated PBS and PEA. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3333–3337, 2004