IPDI和PEG对乳酸直接熔融缩聚物的扩链改性  

Chain extension and modification of polylactic acid homopolymer synthesized via direct melt copolycondensation by IPDI/PEG

作　　者：樊国栋[1] 杨海燕[1] 贾发瑞 张昭[1] 

机构地区：[1]陕西科技大学化学与化工学院,陕西西安710021 [2]陕西彩虹光电材料总公司研究开发部,陕西咸阳712000

出　　处：《合成树脂及塑料》2009年第2期43-46,共4页China Synthetic Resin and Plastics

基　　金：陕西省科技攻关资助项目(2008K07-32);陕西省咸阳市科技计划资助项目(XK07011-2);陕西科技大学研究生创新基金资助

摘　　要：以乳酸为原料,锌酸亚锡[Sn(Oct)_2]为催化剂,在170℃,0.09 MPa下反应8 h,直接熔融缩聚合成聚乳酸(PLA)均聚物。当w[Sn(Oct)_2]为0.8%时,PLA均聚物的黏均分子量(M_η)最大。将其与异佛尔酮二异氰酸酯(IPDI)反应,当n(—OH)/n(—NCO)为1.5时,在176℃,0.09 MPa下反应13 min,得到PLA共聚物的M_η最大。PLA共聚物与不同数均分子量的聚乙二醇(PEG)共聚合成PLA-PEG(PLEG)系列。用凝胶渗透色谱仪、傅里叶变换红外光谱仪、差示扫描量热仪、接触角测试仪等表征聚合物。结果表明:PLEG-6000的聚合程度最好;PLEG-800的玻璃化转变温度最小,且亲水性能最好。Polylactic acid （PLA） homopolymer was synthesized via melt copolycondensation from lactic acid in the presence of Sn（Oct）2 as catalyst under the conditions of temperature of 170 ℃, pressure of 0.09 MPa and reaction time of 8 hours. When Sn（Oct）2 content was 0.8%, the visco-average molecular mass （Mn） of the PLA homopolymer reached its maximum value. In the case of reacting the PLA homopolymer with isophorone diisocyanate （IPDI） at 176℃, 0.09 MPa and n（--OH）/n（--NCO） ratio of 1.5 for 13 min, the resultant PLA copolymer also possessed the maximum Mn. A series of copolymers of PLA and polyethylene glycol （PLEG） were synthesized via the reaction of the PLA homopolymer with PEG having diverse number-average molecular mass. All the homo-and copolymers so prepared were characterized by gel permeation chromatography （GPC）, Fourier transform infrared spectroscopy （FFIR）, differential scanning calorimetry （DSC） and contact angle analysis. The results indicate that the PLEG-6000 copolymer has the optimum polymerization degree and the PLEG-800 copolymer has the minimum glass transition temperature （Ts） and the optimum hydrophilicity among the polymers.

关 键 词：聚乳酸-聚乙二醇 异佛尔酮二异氰酸酯 直接熔融缩聚 扩链 

分 类 号：TQ316.334[化学工程—高聚物工业]