水溶性涂布液共聚酯的制备及性能研究

Preparation and Properties of Water Soluble Copolyester for Coating Solution

实验以对苯二甲酸(PTA)、间苯二甲酸(IPA)、间苯二甲酸-5-磺酸钠(5-SSIPA)、乙二醇(EG)、二羟甲基丙酸(DMPA)为基本原料,钛酸四丁酯做催化剂,通过两步法熔融缩聚合成了一种水溶性聚酯(WSPET)。采用六甲氧基甲基三聚氰胺(HMMM)作为反应交联剂,对双向拉伸聚酯(BOPET)薄膜进行涂布改性,制备BOPET/WSPET复合薄膜。探究了不同5-SSIPA、DMPA用量对样品的接触角、热学性能、耐水煮性、光学性能和物理性能的影响。结果表明:随着5-SSIPA用量的增加,水溶性聚酯亲水性增强,玻璃化转变温度升高,耐水煮性能降低。随着DMPA用量增大,水溶性聚酯亲水性增强,耐水煮性能增强,同时复合膜的铅笔硬度、附着力明显提高,但柔韧性降低。当5-SSIPA添加量为50%(相对于IPA物质的量),DMPA添加量为250%(相对于IPA物质的量)时,样品综合性能达到最佳。

In this experiment,water soluble polyester(WSPET)was synthesized by two-step esterification with terephthalic acid(PTA),isophthalic acid(IPA),sodium phthalic acid-5-sulfonate(5-SSIPA),ethylene glycol(EG)and dihydroxymethyl propionic acid(DMPA)as raw materials,tetrabutyl titanate as catalyst.BOPET/WSPET composite membrane was prepared by emulsion crosslinking with hexa(methoxymethyl)melamine(HMMM)as crosslinking agent by the coating method.The effects of different amounts of 5-SSIPA and DMPA on the contact angle,thermal properties,boiling resistance,optical properties and physical properties of the samples were investigated.The result shows that with the increase of the amount of 5-SSIPA,the hydrophilicity of the water-soluble polyester increases,the glass transition temperature increases,and the boiling resistance decreases.With the increase of the amount of DMPA,the hydrophilicity of the water-soluble polyester is enhanced,the boiling resistance is enhanced,and the pencil hardness and adhesion of the composite membrane are significantly improved,but the flexibility is reduced.When the addition amount of 5-SSIPA is 50%(relative to IPA mole ratio)and the addition amount of DMPA is 250%(relative to IPA mole ratio),the comprehensive performance of the sample is the best.