聚苯丙抗菌乳液的制备及表征

Preparation and Characterization of Antibacterial Poly Styrene Acrylic Emulsion

将苯乙烯、丙烯酸丁酯、甲基丙烯酸正丁酯及末端带有碳碳双键的功能化聚六亚甲基盐酸胍进行乳液聚合反应,得到具有抗菌性能的聚苯丙乳液。分别考察了单体配比、乳化剂用量、引发剂用量及反应温度对聚苯丙抗菌乳液聚合反应的影响,以获得最佳的聚合条件。结果表明,在引发剂质量分数为0.4%~0.5%,乳化剂质量分数4%~6%,反应温度70~80℃的聚合条件下,可得到颗粒尺寸均匀适中、稳定的乳液。同时,通过红外光谱、透射电镜和激光粒度分析仪等对乳胶粒子的组成和结构进行了表征。并分别采用稀释法和扩散法测试了抗菌乳液对大肠杆菌的抗菌性能。稀释法实验表明,抗菌乳液的最低抑菌浓度可达4×10-6;扩散法实验表明,经提纯后的抗菌乳液的膜片不存在胍盐低聚物的溶出,但对大肠杆菌有明显的抑菌圈,实现了材料抗菌性能的长效性。

Styrene, butyl acrylate, n-butyl methacrylate and polyhexamethylene guanidine hydrochloride, which have functional terminal carbon-carbon double bonds, were used as comonomers to obtain poly styrene-acrylate emulsion possessing antibacterial properties via emulsion polymerization. The influences of monomer ratio, surfactant and initiator amount and reaction temperature on the reaction of emulsiontpolymerization of latex were investigated to obtain optimal polymerization conditions. The results show that the stable emulsion with even particle size was obtained when the polymerization was processed with 0.4% --0.5% of initiator and 2% --6% of emulsifier at 70-- 80 12. The composition and structure of the latex particles were characterized by FT-IR, TEM and laser particle size analyzer. Meantime, the methods of dilution and diffusion were employed to study antibacterial properties of latexes against Escherichia coll. Dilution experiments show that the minimum inhibitory concentration （MIC） of antibacterial latex is low to 4×10^-6; diffusion method experiments demonstrate that a significant inhibition zone appeares and guanidine salt oligomer does not leach from the membrane of purified antibacterial latexes, which renders the membrane antibacterial for a long term.