包装用BA/St改性水性聚氨酯及其粘接性能的研究

Study on waterborne polyurethane modified by BA/St for packaging and bonding performance

以丙烯酸丁酯(BA)和苯乙烯(St)为改性剂、双丙酮丙烯酰胺(DAAM)为交联剂,采用自由基引发聚合工艺,制备出高性能的BA/St改性水性聚氨酯(WPU)包装用胶粘剂。采用红外光谱(FT-IR)仪和粒度分析仪对乳液的结构和性能进行了分析,讨论了R值(即-NCO/-OH的物质的量比)、改性剂、St和交联剂用量对胶粘剂粘接强度的影响。试验结果表明:当R=1.1、w(改性剂BA/St)=28%(相对于WPU而言)、w(St)=30%(相对于BA/St而言)和w(DAAM)=2%时,乳液的粘接性能最佳;由该乳液配制的胶粘剂可以满足多种复合软包装膜的使用要求。

With butyl acrylate （BA） and styrene （St） as modifiers,and diacetone acrylamide（DAAM） as cross linker,the high performance waterborne polyurethane（WPU） adhesive modified by BA/St for packaging was prepared by free radical polymerization process. The structure and performance of the emulsion were characterized by Fourier transform infrared spectroscopy（FT-IR） and particle size analyzer. The influences of R value（namely molar ratio of -NCO to -OH）,the contents of modifier,St and DAAM were discussed on bonding strength for the adhesive. The experiment results showed that the bonding performance of emulsion was best when R value was 1.1 ,mass fraction of modifier（BA/St） was 28% in WPU,mass fraction of St was 30% in BA/St and mass fraction of DAAM was 2%. The adhesive which was made from the emulsion could meet application requirement of manifold composite laminated films for soft packaging.