水性PU嵌段离聚体的合成及其溶液行为研究

摘要

以聚乙二醇(PEG)、异佛尔酮二异氰酸酯(IPDI)和二羟甲基丙酸(DMPA)为共聚单体,二月桂酸二丁基锡(DBTL)为引发剂,三乙胺(TEA)为中和剂,采用溶液聚合法合成得到规整嵌段离聚体.以不同相对分子质量的PEG为软段,采用不同的n(DMPA)∶n(PEG)、n(-NCO)∶n(-OH)比例进行合成,获得了一系列嵌段离聚体.通过粒径、比浓黏度、旋转黏度、电导率和临界聚沉浓度,对离聚体的溶液行为进行了研究.水性PU嵌段离聚体粒径都在200nm左右；比浓黏度大多数都在1 min以内；水性PU嵌段离聚体是剪切变稀的,旋转黏度是转子在40 r/min条件下测得的；随PEG相对分子质量增大,水性PU嵌段离聚体的临界聚沉浓度p(Cc.c)减小.%With PEG/IPDI/DMPA as comonomer, DBTL as initiator, TEA as neutralizing agent, regular block ionomers were synthesized by solution polymerization process. With PEG (with different molecular weight) as soft segment, at different n(DMPA): n( PEG) ,n(-NCO): n(-OH) , a series of block ionomers were obtained. Solution behavior of block ionomers was studied, in terms of the particle size, reduced viscosity, BF viscosity, conductivity and critical congregating concentration (p(Cc. C) ). Particle sizes of all waterborne PU block ionomers were around 200 nm; most of their reduced viscosity was within 1 min; water-borne PU block ionomers were shear thinning systems, the BF viscosity was measured at the speed of 40 rpm; with PEG molecular weight increasing, p(Cc. C) of waterborne PU block ionomers decreased.