文献类型：期刊文献

英文题名：In Situ synthesis of multiblock copolymers of poly(?-caprolactone) with different poly(ether diols) based polyurethane by reactive extrusion

作者：Weng, Shengguang[1];Xia, Zhean[1];Chen, Jianding[1];Gong, Luanluan[1];Xu, Ruijun[1]

机构：[1]E China Univ Sci & Technol, Sch Mat Sci & Engn, Key Lab Ultrafine Mat, Shanghai Key Lab Adv Polymer Mat,Minist Educ, Shanghai 200237, Peoples R China

年份：2012

卷号：124

期号：5

起止页码：3765

外文期刊名：JOURNAL OF APPLIED POLYMER SCIENCE

收录：;EI(收录号：20121114851660);WOS:【SCI-EXPANDED(收录号:WOS:000300971400029)】；

基金：Contract grant sponsor: Shanghai International Science and Technology Cooperation Funding; contract grant number: 06SR07103.Contract grant sponsor: Shanghai Leading Academic Discipline Project; contract grant number: B502.Contract grant sponsor: Shanghai Key Laboratory Project; contract grant number: 08DZ2230500.

语种：英文

外文关键词：block copolymers; polyurethanes; reactive extrusion; ring-opening polymerization

摘要：Polyurethanes with multiblock copolymers of poly(?-caprolactone) (PCL) and poly(tetramethylene oxide) glycol (PTMG) or poly(ethylene glycol) (PEG) as a soft segment were synthesized in situ via reactive extrusion from ?-caprolactone (CL) and 4,4'-diphenylmethane diisocyanate (MDI). The titanium alkoxide mixture generated from an ester-exchange reaction between titanium propoxide [Ti(OPr)4], and excessive PTMG or PEG was used as an initiator and catalyst. Compared to the reported fabrication of polycaprolactone-based polyurethane (PCLU), the in situ reactive extrusion preparation not only explored a new rapid route for the fabrication of PCLU but also offered a simplified, controllable approach for the production of PCLU in a successive mass scale. A series of PTMGPCLUs and PEGPCLUs with different PCL block-average degrees of polymerization (DPn's) were prepared by only an adjustment of the relative concentration of CL in the reaction system, with a certain constant molar ratio of MDI to titanium alkoxide. 1H-NMR, gel permeation chromatography, and differential scanning calorimetry results indicate that all of the CL monomers were converted in the polymerization, and the molecular weight of the copolymers was about 8 x 10(4) g/mol with a polydispersity index of approximate 2.4. With an increase in the PCL block-average DPn in PTMGPCLU from 25 to 40, the tensile strength increased from 16.5 to 22.7 MPa, and the melting point increased from 46.1 to 49.5 degrees C. It was also verified by PEGPCLU prepared with organic Ti of lowered content in the initiator mixture that the mechanical properties could be greatly affected and dropped with decreasing content of organic Ti in the initiator mixture. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012