The modification of surface properties of polypropylene (PP) substrates has attracted much attention in fundamental science and industrial applications. Primer treatment is one of the most simple and facile surface modification methods. This study used polyethyleneimine (PEI) as a surface activator for bonding polypropylene substrates with ethyl cyanoacrylate (ECA) adhesive. We have understood the effect of various factors such as the open time, solvent composition, optimum concentration and molecular weight of the primer. The bonding strength was maximum when the substrates were bonded immediately on priming. It was also observed that the solvent composition plays a minor role in the development of bond strength. The bond strength of substrates coated with a primer having a PEI concentration as low as 0.05% showed better results and was, in fact, three times better than the unprimed ones. It was also concluded that a low molecular weight PEI performs better than one having a higher molecular weight. DSC results confirmed that an improvement in strength is due to an increase in the molecular weight of the ECA polymer, which occurs in the presence of PEI molecules.

在基础科学和工业应用中，聚丙烯（PP）基材表面性能的改性已引起广泛关注。底漆处理是最简单，最方便的表面修饰方法之一。这项研究使用聚乙烯亚胺（PEI）作为表面活化剂，用氰基丙烯酸乙酯（ECA）粘合剂粘合聚丙烯基材。我们已经了解了各种因素的影响，例如底漆的开放时间，溶剂组成，最佳浓度和分子量。当底漆立即上底粘合时，粘合强度最大。还观察到溶剂组合物在粘结强度的发展中起次要作用。PEI浓度低至0.05％的底漆涂层的基材的粘结强度显示出更好的结果，并且实际上是 是没有底漆的三倍。还得出结论，低分子量PEI的性能优于具有较高分子量的PEI。DSC结果证实强度的提高归因于ECA聚合物分子量的增加，这是在PEI分子存在下发生的。