聚乙烯醇大分子单体及其功能微球的制备

Study on the preparation of poly(vinyl alcohol)macromer and functional microspheres

由氨基乙醛二甲基缩醛与丙烯酰氯反应得到N-丙烯酰胺基乙醛二甲基缩醛(NAAADA),在酸性介质中使其与聚乙烯醇(PVA)发生缩醛交换反应,制得了PVA大分子单体(PVA-NAAADA)。用傅里叶红外(FT-IR)、核磁共振(1 H-NMR)对PVA-NAAADA的化学结构进行表征;并以制备的PVA-NAAADA及2-丙烯酰胺-2-甲基丙磺酸(AMPS)为共聚单体,经反相悬浮法制备了具有pH敏感性的交联型PVA功能微球,通过光学显微镜观察了微球的大小与形貌。结果表明:所制备的微球粒径较均一,单分散性良好,在pH=7.0的缓冲溶液中对5-氟尿嘧啶的释药率最大可达到72.3%,具有显著的pH敏感性。

The intermediate N-acrylamidoacetaldehyde dimethyl acetal（NAAADA）was synthesized used aminoacet- aldehyde dimethyl acetal with acryloyl chloride. Poly（vinyl alcohol） （PVA） macromer（PVA-NAAADA） was synthesized by acetal exchange reaction of NAAADA and PVA in acidic medium. The structure of PVA-NAAADA was characterized by FT-IR and 1H NMR. A series of pH-sensitive crosslinked PVA microspheres were prepared by inverse suspension poly- merization of PVA-NAAADA and 2 acrylamide-2-methylpropanesulfonie acid. The results from optical microscope observa tion showed that PVA microspheres with pH sensitivity had uniform size. Moreover,the release ratio of 5-Fluorouracil（5- Fu）from PVA microspheres reached 72.3 % in pH= 7.0 buffer solution.