摘要：为研究一种新型两性聚电解质渗透汽化膜分离材料,利用沸腾、高速搅拌的无皂乳液聚合法合成纳米聚丙烯酰胺-丙烯酸,经Hoffman降解制备纳米聚乙烯铵-丙烯酸钠。利用红外光谱、扫描电镜和激光粒度分析仪对纳米聚乙烯铵-丙烯酸钠进行结构表征,测试不同pH值时聚乙烯铵-丙烯酸钠膜的耐水性。对不同浓度、不同有机物-水体系中的溶胀度和吸水速率进行测试。结果表明:聚乙烯铵-丙烯酸钠粒径在24 nm左右、pH≈5(接近等电点)时,聚乙烯铵-丙烯酸钠膜的耐水性最好,适合乙醇、丙酮中水的分离。

关键词： 乳液聚合；纳米聚乙烯铵-丙烯酸钠；两性聚电解质；渗透汽化膜

Abstract： In order to develop a new type of polyamphoteric electrolyte pervaporation membrane materials， nano-sized polyacrylamide-acrylic acid （PAM-AA） particles were prepared using the soap-free emulsion polymerization method and boiling at high temperature and became nano-sized polyethylene ammonium-sodium acrylate（PVAM-SA） particles by Hoffman degradation reaction. The structure of PAM-SA was characterized using Fourier transform infrared spectroscopy （FTIR） and scanning electron microscopy （SEM） and laser particle size analysis. The water-resistant properties of the PVAM -SA polyampholite membrane under defferent pH values were studied. The degree of swelling and water-absorbent rate of the PVAM -SA polyampholite membrane were tested in de f ferent organic-water system， with a series of concentrations. The results showed that the size of PVAM-SA particles were about 24 nm. The water-resistant properties of the PVAM-SA polyampholite membrane were better for ethanol-water system and acetone-water system at pH≈5 （near the isoelectric point）. 

Keywords： emulsion polymerization； nano-sized polyethylene amm on ium-sodium acrylateparticles； polyampholyte； pervaporation membranes