单组分水性聚氨酯复膜胶研制

Develpoment of one-component waterborne polyurethane film-laminating adhesive

溶剂型复膜胶一般为双组分,使用不便,而且含大量有机溶剂影响安全和环保。在软包装等领域,已经越来越多地被水性复膜胶产品替代。水性聚氨酯胶粘剂(WPU)为单组分,性能优良。本课题在丙酮法合成水性聚氨酯的技术基础上,分别采用熔融分散法和预聚体分散法合成WPU复膜胶。通过综合比较,性价比较好的预聚体分散法是合成WPU复膜胶的理想方法。用MDI-2460和TDI的混合异氰酸酯、聚酯多元醇PD-56、中和前预聚体-NCO含量在2.5%～3.0%时,可合成出性能稳定、单组分,对透明PE/PE镀铝、PET镀铝/BOPP、透明PE/黑白膜等复合性能良好,初粘性可达2N/15mm以上的WPU,基本不用熟化即可直接分切。

Generally,the solvent-based film-laminating adhesives are used in the form of two components,thus its ues is inconvenient,meanwhile it brings some safe and environment friendly problems.By comparison to solvent-based adhesives,the waterborne polyurethane （WPU） adhesives,as a environment-friendly material,are used widely in soft packing,which are used in the form of one component and has excellent performance.On the basis of waterborne polyurethane synthesized by acetone method,the one-component waterborne polyurethane was synthesized by prepolymer dispersing process and metl dispering process.Through comparisions of techniches,characters and productive efficiency,prepolymer dispersing process with excellent performance and low cost is superior to metl dispering process.The comprehesive comparison of cost performance indicated that the prepolyme dispersing method is a perfact method of synthesis of WPU film-laminating adhesives.When the NCO group content of the prepolymer is 2.5% to 3% before neutralization the one-component WPU with stable performance and tackness of over 2N/15 mm can be synthesized with the mixture of MDI-2460 and TDI and the polyester polyol PD-56,which has excellent laminating performance for the films,such as transparent PE/aluminized PE,aluminized PET/BOPP and transparent PE/black-white film,and can be slit without curing.