丙烯腈-醋酸乙烯酯水相沉淀聚合产物的研究

Research on Acrylonitrile-Vinyl Acetate Copolymers Polymerized in Water

采用水相沉淀聚合法制备了摩尔含量为0%~25%醋酸乙烯酯（VA c）的丙烯腈（AN）-醋酸乙烯酯（VAc）共聚物,并采用红外光谱（FT-IR）、元素分析、差热分析（DSC）、X射线衍射（XRD）和乌氏黏度计等方法对聚合产物进行了表征。结果表明,聚合产物中VAc的含量低于投料配比中VAc的含量;随VAc比例的增加,聚合物的熔点降低,分解温度先升高后又降低。VAc的摩尔含量为15%~20%时共聚物的分子量为2.8×10^4~3.1×10^4。VAc摩尔含量为10%时共聚物的分解温度为364℃,而熔融温度仅为222℃。由于第二单体VA c的加入,可使共聚物的熔点降低到分解温度之下。

Fabrication and characterization of melt processable polyacrylonitrile copolymers, which were potentially used as fiber materials, were studied. Poly （acrylonitrile-vinyl acetate） copolymers containing up to 25 mol% of vinyl acetate （VAc）were synthesized using Redox process. The copolymers were characterized using Fourier Transform Infrared Spectroscopy （FT- IR）, Elementary Analysis, Differential Scanning Calorimetry （DSC）, X-ray Diffraction （XRD） and Ubbelohde viscometer. The results show that, the molar ratio of the VAc in copolymers is lower than that of the feed ratio. The melting temperature of copolymers moves to the lower tem- perature while the decomposition temperature of the copolymers goes up and then down with the increase of the VAc molar ratio. The molecular weight of copolymer ranges from 2.8×10^4to 3.1 × 10^4when the molar ratio of VAc is 15% and 20% respectively. The decomposition temperature of eopolymer molar eontaining 10% VAe rises up to 364 C while the melting temperature depresses to 222 C. The incorporation of VAc into the system reduces the inching point, which is lower than the decomposition temperature. These copolymers are potentially useful for melt-pro- cessable PAN fibers.