化学气相沉积聚合制备聚溴代对亚苯基二亚甲基及其性能的研究

用化学气相沉积(CVD)聚合法制备了聚溴代对亚苯基二亚甲基(PPX-B r)膜,采用FT-IR和元素分析的方法证实了其化学结构。对膜溶解性和抗化学氧化性能的研究表明,聚溴代对亚苯基二亚甲基膜具有优异的耐溶剂性和抗化学氧化性能。对其热性能的研究表明,溴的引入使得膜的玻璃化转变温度降低,室温柔性增强,热降解性能与聚氯代对亚苯基二亚甲基(PPX-C)相似。与PPX膜相比,溴的引入对膜的亲水性能影响不大,而水汽渗透率明显降低,具有更好的防潮性。

Chemical Vapor Deposition Polymerization and Properties of Poly (Bromo-p-Xylylene-co-p-Xylylene)

Chemical vapor deposition(CVD) polymerization can be used to prepare poly(p-xylylene)(PPX),which shows promising features like absolute conformance to substrate topology,pinhole-free coverage even in thin films,the ability to penetrate and cover complex geometries,and extraordinarily high chemical inertness and purity compared to conventional polymer coating.However,the surface adherence of PPX is limited due to its asymmetrical structure.It will be useful to introduce some polar side-group into the backbone of PPX.Poly(bromo-p-xylylene-co-p-xylylene)(PPX-Br) was prepared by chemical vapor deposition(CVD) polymerization in present work.The chemical structure of the resulted polymer was confirmed by FT-IR and elemental analysis.It is found that PPX-Br membrane has the same good solvent resistant and high chemical oxidation resistant as PPX.Thermogravimetric analysis(TGA) and differential scanning calorimetry(DSC) were used to study the thermal properties of PPXBr and PPX membranes.It is found that the initial degradation temperature and T_g of PPX-Br membranes are reduced with the introduction of bromine group as side groups,which is similar to that of commercial PPX-C.It seems that the hydrophilicity of PPX-Br membranes is similar to that of PPX.The vapor permeability of PPX-Br membranes is reduced significantly compared with PPX.The moisture-proof ability of PPX-Br film is improved.