聚甲基乙撑碳酸酯乳液的制备及应用性能研究

Study on Preparation and Application Properties of Polypropylene Carbonate Emulsions

关键词:  聚甲基乙撑碳酸酯  乳液  乳化剂  乳化工艺

Key Words:polypropylene carbonate  emulsion  emulsifier  emulsification process

摘要:采用不同乳化剂对聚甲基乙撑碳酸酯（PPC）树脂进行乳化，以乳液的乳化率及粒径为考核指标对乳化工艺进行优化。结果表明，优化的乳化剂组合为十六烷基三甲基溴化铵和吐温80，其绝干质量比为3∶1；优化后的乳化工艺为：乳化剂用量15%，内外相体积比3∶4，油相为质量分数25%的PPC树脂/二氯甲烷溶液，皂液温度30 ℃，剪切速率>10 000 r/min，剪切时间4~6 min，添加质量分数2%的聚乙烯醇作为乳液保护胶体。乳化后PPC树脂的热封性能和阻隔性能均有不同程度降低，但能满足高热封压力的应用场景。

Abstract:Emulsification of poly(propylene carbonate) （PPC） resin was investigated using different emulsifiers， with emulsification efficiency and particle size of emulsion serving as evaluation indices for process optimization. The results showed that the optimal emulsifier combination consisted of cetyltrimethylammonium bromide （CTAB） and Tween 80 at an absolute dry mass ratio of 3∶1. The optimized emulsification parameters were determined as follows： emulsifier dosage of 15%， internal-to-external phase volume ratio of 3∶4， oil phase comprising dichloromethane solution containing 25% PPC resin， saponification temperature maintained at 30 ℃， shear rate exceeding 10，000 r/min， shear duration of 4~6 min， with additional incorporation of 2% polyvinyl alcohol as a protective colloid for the emulsion. Post-emulsification analysis revealed discernible reductions in both heat-sealing performance and barrier properties of PPC resin. Nevertheless， the modified material retained sufficient functionality to satisfy application requirements demanding high heat-sealing pressure.