功能化石墨烯改性无胺型水性聚氨酯的制备

Preparation of Functionalized Graphene Modified Amine-Free Waterborne Polyurethane

摘要:

以聚已内酯二元醇（PCL），甲苯二异氰酸酯（TDI），甲基丙烯酸甲酯（MMA）为主要原料，合成水性聚氨酯-丙烯酸酯乳液（WPUA）预聚体，将氧化石墨烯经偶联改性纳米SiO2所得产物与预聚体进行原位聚合，并同时采用羧酸型亲水扩链剂和磺酸型亲水扩链剂，用自乳化法制备了具有无溶剂、零VOC特点的经功能化石墨烯改性的水性聚氨酯-丙烯酸酯复合乳液（SiO2-NH2-go/WPUA），并对功能化石墨烯的用量和复合乳液及其胶膜进行测试和表征。与水性聚氨酯-丙烯酸酯（WPUA）相比，复合乳液（SiO2-NH2-go/WPUA）具有更好的耐温性及胶膜性能，当SiO2-NH2-go质量分数为0.75%时，复合乳液胶膜较未改性乳液胶膜相比，热分解温度提高77.32℃；拉伸强度提高到81.28Mpa;该复合乳液配制的胶黏剂在铝箔/PVC薄膜的T-剥离强度达到15.4N；易氧化物等指标符合药品包装容器标准，表明该水性聚氨酯胶黏剂适用于医药包装。

Abstract:

Using polycaprolactone diol (PCL), toluene diisocyanate (TDI) and methyl methacrylate ( MMA ) as main raw materials, waterborne polyurethane-acrylate emulsion (WPUA ) prepolymer was synthesized. the product obtained by coupling modified nano - SiO2 with graphene oxide was polymerized in situ with the prepolymer. at the same time, carboxylic acid hydrophilic chain extender and sulfonic acid hydrophilic chain extender were used to prepare functionalized graphene-modified waterborne polyurethane-acrylate composite emulsion ( SiO2-NH2-go/ WPUA ) with solvent-free and zero VOC characteristics by self-emulsifying method .Compared with waterborne polyurethane-acrylate ( WPUA ), the composite emulsion ( SiO2-NH2-go/ WPUA) has better temperature resistance and film properties. when the mass fraction of SiO2-NH2-go is 0.75 %, the thermal decomposition temperature of the composite emulsion film is 77.32 ℃ higher than that of the unmodified emulsion film;The tensile strength increased to 81.28 MPa;and the T- peel strength of the adhesive prepared by the composite emulsion reached 15.4 N in aluminum foil / PVC film;Indicators such as easy oxides meet the standards for pharmaceutical packaging containers, indicating that the waterborne polyurethane adhesive is suitable for pharmaceutical packaging.