选择性接聚乙烯醇枝聚醚氨酯的合成及其血液相容性

合成了α－甲基，ω－（２，３－环氧丙基）－聚乙二醇醚（Ⅱ）．经水解得到悬挂聚乙二醇（ＰＥＧ）枝的丙二醇－２，３（Ⅲ）．用二元醇（Ⅲ）为扩链剂制得了在硬链段上接有ＰＥＧ枝的聚醚氨酯（Ｈ－ＰＥＵ）．以四氢呋喃与少量大分子单体（Ⅱ）进行正离子开环共聚合制得每个链接有约１．３个ＰＥＧ枝的聚丁二醇（Ⅳ），用以合成了在软链段上接有ＰＥＧ枝的聚醚氨酯（Ｓ－ＰＥＵ）．ＥＳＣＡ及抗凝血性研究结果表明，不同位置接枝的ＰＥＵ，其表面都有明显的聚醚链段富集．Ｓ－ＰＥＵ抗凝血复钙时间只比未接枝者增长约２０％，而Ｈ－ＰＥＵ则增约一倍，比Ｓ－ＰＥＵ增约６０％．随ＰＥＧ最增大，复钙时间增长．

SYNTHESIS OF POLY(ETHER-URETHANE) SELECTIVELY GRAFTED ONTO DIFFERENT SEGMENTS WITH PEG HYDROGEL AND ITS ANTITHROMBOGENICITY

?methyl, ω-(1,2-epoxy) propyl poly(ethylene glycol)(Ⅱ) was prepared and hydrolyzed to a glycol(Ⅲ) with a pendent poly(ethylene glycol) (PEG)chain. The glycol(Ⅲ) was used as the chain extender in preparing poly(etherurethane) with PEG grafted onto the hard segments (H-PEU).The macromer(II) cationically copolymerized with tetrahydrofuran to give a copolyether (Ⅳ) grafted with PEG chain. Using copolyether(Ⅳ) with about 1.3grafts per molecule, the S-PEU with PEG grafted onto soft segments was synthesized.The S-PEU as well as H-PEU had a soft segment-rich surface as shown by ESCA study. The recalcification times for S-PEU and H-PEU increased 20% and 100%, respectively, as compared with that of ungrafted PEU. With increasing the PEG content the antithrombogenicity increased.