环保型丙烯酸酯改性水性聚氨酯胶黏剂的合成研究

Synthesis of Environmental Friendly Acrylate Modified Waterborne Polyurethane Adhesive

水性聚氨酯(WPU)具有挥发性有机化合物(VOC)含量低、应用范围广等优点,但也存在各种耐性、力学性能差等缺点。采用高机械强度的丙烯酸酯对WPU进行改性可以得到综合性能较好的产品。由聚丙二醇(PPG)和异佛尔酮二异氰酸酯(IPDI)为主要原料、1,2—丙二醇为扩链剂、2,2—二羟甲基丙酸(DMPA)和甲基丙烯酸羟丙酯(HPMA)为亲水单体,合成高分子量的聚氨酯预聚体,再用过硫酸钾(KSP)引发软单体丙烯酸丁酯(BA)与硬单体苯乙烯(St)共聚,可制备水性聚氨酯胶黏剂乳液。测试结果表明,当IPDI与PPG的质量比为2∶3,DMPA含量为6%,丙二醇含量为5%,丙烯酸酯混合单体含量为60%,软硬单体质量比为3∶2时,所得丙烯酸酯改性聚氨酯胶黏剂(WPUA)性能良好,其黏结强度明显超过WPU。

Waterborne polyurethane(WPU) has the advantages of low content of volatile organic compounds(VOC) and wide application, but it also has some disadvantages such as poor endurance and mechanical properties. WPU with high mechanical strength acrylic ester can be modified to obtain better comprehensive properties. In this research, the waterborne polyurethane emulsion was prepared by using polypropylene glycol(PPG) and isophorone diisocyanate(IPDI) as main raw materials, 2,2—dihydroxymethylpropionic acid(DMPA) as chain extender, hydroxypropyl methacrylate(HPMA) as the coupling agent, 1,2—propanediol as chain extender. After determining the optimal process, potassium persulfate(KSP) was used to initiate the copolymerization of soft monomer butyl acrylate(BA) and hard monomer styrene(St) to prepare waterborne polyurethane adhesive emulsion. It is revealed that when IPDI∶PPG ratio is 2∶3, DMPA content is 6%;when propylene glycol content is 5%, acrylic mixed monomer content is 60%;when the ratio of hard and soft monomer is 3∶2, the obtained acrylate modified polyurethane adhesive(WPUA) has good performance, and its bond strength is obviously higher than that of WPU.