BOPP用水性丙烯酸酯胶黏剂的制备及其性能

Preparation and Properties of the Water-Based Acrylate Adhesive for Biaxially Oriented Polypropylene

为了应对快递行业高速发展带来的双向拉伸聚丙烯(BOPP)用胶黏剂需求的增加,本研究旨在开发一种适用于BOPP膜的水性丙烯酸酯胶黏剂。采用半连续乳液聚合工艺,考察了丙烯酸(AA)、甲基丙烯酸β-羟乙酯(HEMA)两种功能单体对胶黏剂黏度、固含量及粒径的影响规律;并采用拓展流变仪进一步分析了胶黏剂的结构、流变及黏结性能三者关系;评价了该胶黏剂在BOPP基材上的黏结强度。研究结果表明,复合功能单体含量对于乳液粒径影响不明显,乳液粒径维持在250 nm左右;复合功能单体可强化流体分子间的相互作用,使得胶黏剂的黏度增加;流变学和接触角分析表明,含质量分数2%复合功能单体的胶黏剂内聚能最小,分子链柔顺,接触角为92.4°。这些性质有助于胶黏剂在BOPP膜表面浸润,从而提高黏结强度。质量分数2%复合功能单体合成的丙烯酸酯胶黏剂性能最佳,在BOPP膜上的剥离强度达21.44 N/50mm,兼具了低黏、高固特点,易于施工,具有较好的市场应用前景。

To cope with the increasing demands for biaxially oriented polypropylene(BOPP)adhesives brought about by the rapid development of express industry,this study aimed to develop a water-based acrylate adhesive suitable for BOPP films.A semi-continuous emulsion polymerization process was employed to investigate the effects of acrylic acid(AA)andβ-hydroxyethyl methacrylate(HEMA)on the viscosity,solid content,and particle size of the adhesives.The relationships among structures,rheology and adhesive properties of the adhesives were analyzed using an extensional rheometer.Adhesive strength on the BOPP substrate was evaluated.The results indicate that the addition of composite functional monomers has little effect on the emulsion particle size,the particle size of the emulsion is maintained at about 250 nm.The composite functional monomers could enhance the interactions between fluid molecules,leading to an increase of adhesive viscosity.Rheology and contact angle analyses show that the adhesive with a 2%mass fraction composite functional monomer exhibits the lowest cohesive energy,flexible molecular chains,and a contact angle of 92.4°.These properties facilitate the adhesives to infiltrate on the surface of the BOPP film,improving the adhesive strength.The acrylate adhesive synthesized via a 2%mass fraction composite functional monomer possesses the best performances,with a peel strength of 21.44 N/50mm on the BOPP film,low viscosity,and high solid content.It has a good market application prospect.