Surface modification of polypropylene nonwoven fabrics by grafting of polydopamine

A nonwoven fabrics based on 3-isopropenyl-alpha,alpha '-dimethylbenzene isocyanate grafting polypropylene (PP-g-TMI) was modified with dopamine both by covalent reaction and by polymer layer deposition involving straightforward self-polymerization (PP-PDA) to improve the hydrophilic property of polypropylene nonwoven fabrics. The functionalized surfaces were characterized by structural and morphological analysis combined with the rheological property to confirm the location and dispersion of PDA. The water contact angle, water absorption ability, and the vapor transmission rate were examined to evaluate the hydrophilicity performance of modified materials. It was found that the aggregated small particles on PP nonwoven fabric could result in a heterogeneous surface, and the modified PP nonwoven fabric with dopamine indicated a lower water contact angle and better hydrophilicity that the water absorption ability nearly soared to ten times that of PP nonwoven fabric without PDA.