聚对亚苯基二亚甲基薄膜的表面化学改性及其肝素化反应

CHEMICAL SURFACE MODIFICATION AND HEPARINIZATION OF POLY(p-XYLYLENE) MEMBRANES

采用化学气相沉积聚合(CVDP)法制备聚对亚苯基二亚甲基(PPX),再通过与酸酐的化学表面反应将丁酸酰基和马来酰基引入PPX薄膜的表面,制得表面带活性取代基的PPX.改性后的薄膜表面粗糙度略有增加,但仍旧维持在10nm以内.改性后的薄膜水接触角减小,减小幅度达到十几度,表面亲水性大幅度提高.丁二酸酐表面改性后薄膜的抗化学氧化时间不变,马来酸酐表面改性后薄膜的抗氧化时间略有下降,但抗氧化时间都大于30h,仍具有优异的抗化学氧化性能.丁酸酰基和马来酰基取代PPX肝素化反应后膜中的肝素含量在7μg/cm2左右,肝素化后薄膜的抗凝血性能得到明显提高.

Poly （p-xylylene）（ PPX ） membranes were prepared by chemical vapor deposition polymerization. Chemical surface modification of PPX membranes by succinic anhydride and maleic anhydride was carried out. Thus the active substituting groups of carboxyl have been successfully introduced into the surface of PPX membranes. The surface roughness of PPX after modification increases a little but still within 10 nm. The water contact angle after the modification decreases obviously.The antioxidation time of PPX-SM-COCH2CH2COOH is the same as PPX of 35 h, while the time of PPX-SM-COCH = CHCOOH decreases 3 h due to the existence of double bond in the membranes. The heparin content of surface modified PPX after heparinization is near 7 μg/cm^2. The platelet adsorption test shows that the herinized PPX membranes have good blood compatibility. The improvement of blood compatibility is mainly concerned with the surface heparin content and whether the heparin molecules could maintain the anticruor configuration freely.