pH敏感型甲基丙烯酸氨烷基酯共聚物乳液的制备及应用

Preparation and Application of pH Sensitive Emulsion of Aminoalkyl Methacrylate Copolymer

采用乳液聚合法,以甲基丙烯酸二甲氨基乙酯(DM)、甲基丙烯酸甲酯(MMA)、甲基丙烯酸丁酯(BMA)为主要单体,选用阳离子型和非离子型乳化剂为复合乳化剂体系,过硫酸钾作为引发剂,制备了一系列分子链中含有叔胺基的甲基丙烯酸氨烷基酯共聚物乳液。利用傅里叶变换红外光谱仪、差示扫描量热仪等对共聚物结构和玻璃化转变温度(T_g)进行表征,并讨论了单体配比、复合乳化剂及引发剂用量等对乳液稳定性的影响。结果表明,当DM/MMA/MBA质量比为6/3/3,复合乳化剂体系及引发剂用量分别为单体总质量的4.5%和0.65%时,制得的乳液黏度、粒子粒径和滤出物含量总体上最小,乳液最为稳定,共聚物的T_g为40.8℃。该材料可用于pH敏感型包覆材料,用其包衣的药片在人工胃液中20min左右即可完全崩解,具有很好的崩解效果。

A series of aminoalkyl methacrylate copolymer emulsions with tertiary amines in molecular chains were prepared by emulsion polymerization taking dimethylaminoethyl methacrylate(DM),methyl methacrylate(MMA)and butyl methacrylate(BMA)as the main monomers,the cationic and non-ionic emulsifiers were chosen as the compound emulsification system and potassium persulfate as the initiator.The structure and glass transition temperature(Tg)of the copolymers were characterized by Fourier transform infrared spectroscopy and differential scanning calorimetry.The effects of monomer ratio,emulsifier system content and initiator content on the stable performances of the emulsions were also studied.The results show that,when the mass ratio of DM/MMA/MBA is 6/3/3,the contents of the compound emulsification system and initiator are 4.5%and 0.65%of monomers total mass respectively,the viscosity,particle size and filtrate substance content of the emulsion are minimum in total and the most stable emulsion is gained,Tg of the copolymer is 40.8℃.The material can be used as pH sensitive coating material,the tablet coated by the material can disintegrate at about 20 min in artificial gastric juice and has good disintegrant effects.