新型甲基丙烯酸甲酯功能聚合物的制备及性能

Preparation and properties of novel functional polymer of methyl methacrylate

针对聚甲基丙烯酸甲酯(PMMA)热稳定性不佳、易燃烧的问题,制备新型PMMA功能聚合物,赋予其优良的耐热性和阻燃性.首先实施了甲基丙烯酸甲酯与乙烯基咪唑的自由基共聚合反应,制得侧链含有咪唑基团的功能聚合物;进一步利用1-氯丁烷和次磷酸钠对其进行化学修饰,将含磷、氮元素引入聚合物中,成功制备了耐热性能优良的甲基丙烯酸甲酯聚合物.结果表明:当甲基丙烯酸甲酯与乙烯基咪唑的摩尔比例由9∶1减小为5∶5时,共聚反应的单体转化率降低了约20%.采用傅里叶红外光谱(FTIR)和核磁共振氢谱(1H NMR)等技术对改性前后的共聚物进行了详细表征.分析结果显示:聚合所得共聚物含有咪唑基团,证明共聚反应成功进行;改性共聚物含有磷、氮元素,表明共聚物具有阻燃基团,这与燃烧实验结果一致;共聚物热稳定性显著提高,且燃烧性能明显降低.

Low thermal stability and inflammability restricts the application of poly（methyl methacrylate）（PMMA）in some special fields. Firstly,the free radical copolymerization of methyl methacrylate and vinyl imidazole were carried out to synthesize functional polymer containing the imidazole group in the side chains of PMMA. Secondly,the resultant copolymer was directly subject to chemical modification with 1-butyl chloride and sodium hypophosphite,and the flame retardant group was thus introduced into the macromolecular chains. The final polymer with excellent heat resistance was successfully prepared. The results showed that the molar ratio of methyl methacrylate to vinyl imidazole was reduced from 9 ∶ 1 to 5 ∶ 5,the monomer conversion decreased ca. 20%. The chemical structure of the original and modified copolymer was confirmed by FTIR and1 H NMR. The results show that the copolymer possesses imidazole group,which proves that the copolymerization of methyl methacrylate and vinyl imidazole is successfully conducted. The modified copolymers contain phosphorus and nitrogen elements, which indicate that the copolymers have flame-retardant groups. Furthermore,this result is in accordance with the results of combustion experiments.The thermal stability of the copolymers is significantly improved and the combustion performance is obviously decreased.