Hyperbranched polymer with alternating ureido and urethano units was prepared by direct polymerizarion of isophorone diisocyanate(IPDI, A 2) with diethanolamine(DEOA, CB 2) in the absence of catalyst. In the reaction,...Hyperbranched polymer with alternating ureido and urethano units was prepared by direct polymerizarion of isophorone diisocyanate(IPDI, A 2) with diethanolamine(DEOA, CB 2) in the absence of catalyst. In the reaction, one isocyanato group of IPDI reacts fast with amino group of DEOA, generating an intermediate with one isocyanato group and two hydroxyl groups. Now the intermediate formed is a new kind of AB 2 type monomer. Further self-condensation of this AB 2 species leads to hyperbranched poly(urea-urethane). The reaction mechanism was characterized with in situ FTIR. Temperature and concentration have great influence on the polymerization process. When the feed ratio of IPDI to DEOA is equal to \{1∶\}1, no gelation is observed if the reaction temperature within initial several hours is lower than 20 ℃. Cross-linking would occur if the reaction temperature during initial period is high. The degree of branching(DB) of the resulting hyperbranched poly(urea-urethane) is 46.5%-48.5%.展开更多
以丁二酸酐(SA)为交联剂研究了端羟基超支化聚(胺-酯)(HPAE)的交联反应和交联膜的制备。结果表明:SA与HPAE的交联反应分为两个阶段,可以采用溶液法低温涂膜及高温交联得到HPAE/SA交联膜;改变SA的用量可控制膜的交联度,HPAE/SA交联膜的...以丁二酸酐(SA)为交联剂研究了端羟基超支化聚(胺-酯)(HPAE)的交联反应和交联膜的制备。结果表明:SA与HPAE的交联反应分为两个阶段,可以采用溶液法低温涂膜及高温交联得到HPAE/SA交联膜;改变SA的用量可控制膜的交联度,HPAE/SA交联膜的拉伸强度随SA用量的增大而提高,最高可达59.60 M Pa,膜表面的水接触角小于74.3°。展开更多
文摘Hyperbranched polymer with alternating ureido and urethano units was prepared by direct polymerizarion of isophorone diisocyanate(IPDI, A 2) with diethanolamine(DEOA, CB 2) in the absence of catalyst. In the reaction, one isocyanato group of IPDI reacts fast with amino group of DEOA, generating an intermediate with one isocyanato group and two hydroxyl groups. Now the intermediate formed is a new kind of AB 2 type monomer. Further self-condensation of this AB 2 species leads to hyperbranched poly(urea-urethane). The reaction mechanism was characterized with in situ FTIR. Temperature and concentration have great influence on the polymerization process. When the feed ratio of IPDI to DEOA is equal to \{1∶\}1, no gelation is observed if the reaction temperature within initial several hours is lower than 20 ℃. Cross-linking would occur if the reaction temperature during initial period is high. The degree of branching(DB) of the resulting hyperbranched poly(urea-urethane) is 46.5%-48.5%.
文摘以丁二酸酐(SA)为交联剂研究了端羟基超支化聚(胺-酯)(HPAE)的交联反应和交联膜的制备。结果表明:SA与HPAE的交联反应分为两个阶段,可以采用溶液法低温涂膜及高温交联得到HPAE/SA交联膜;改变SA的用量可控制膜的交联度,HPAE/SA交联膜的拉伸强度随SA用量的增大而提高,最高可达59.60 M Pa,膜表面的水接触角小于74.3°。
