离聚物及其共混体系的研究3.基于配位络合的增容作用

通过将苯乙烯(S)与少量的甲基丙烯酸(MAA)或马来酸酐(MA)共聚及甲基丙烯酸正丁酯(nBMA)与4-乙烯基吡啶(4-VP)共聚,从而在聚苯乙烯(PS)及聚甲基丙烯酸丁酯(PBMA)链上分别引入了功能基团羧酸基(-CO-OH)、酸酐基(-CO-O-CO-)和吡啶基(-N)。通过与锌盐作用获得相应的离聚物(Ionomer)。用红外光谱(IR)表征了共聚物和离聚物的形成;差热分析(DSC)测定共聚物、离聚物和共混物的玻璃化转变温度(Tg)。研究结果表明,随着共聚物中功能基团含量的增加或者共聚物形成离聚物后,其玻璃化转变温度(Tg)提高了;而共聚物的共混物因羧酸基与吡啶基间的质子转移作用而提高了相容性。特别是在引入Zn~(2+)的共混物中,增容作用十分明显,这可归结于BMAVP中的吡啶基和SMAA-Zn~(2+)(或SMA-Zn~(2+))中的Zn~(2+)间的配位络合作用的贡献。

Studies on Ionomers and the Related Blends 3. compatibilization based on Coordination complexation

Copolymers of styrene and different contents of methacrylic acid or maleic anhydride (SMAA or SMA)and copolymers of butyl methacrylate and 4-vinyl pyridine (BMAVP) were synthesized. The blends of SMAA (or SMA) and BMAVP and the blends of the corresponding ionomers (neutralized with Zn~(2+)) by solvent casting were examined by IR and DSC. It has been shown that introducing metal-ions to the blends of copolymers apparently improves the miscibility. This miscibility enhancement can be attributed to the coordinate complexation between the pyridine units of BMAVP and the Zn~(2+) of SMAA-Zn~(2+) (or SMA-Zn~(2+)).