Surface enrichment of polypropylene-graft-poly(methyl methacrylate) on polypropylene

To overcome disadvantage of polypropylene induced by its low surface energy, poly(methyl methacrylate) was grafted onto polypropylene and entrapped into polypropylene as macromolecular surface modifier. The effects of copolymer structures, contact dies and content of modifiers on their surface enrichment were studied by attenuated total reflection infrared spectroscopy (ATR-FTIR), contact angle measurements (CDA) and scanning electron microscopy (SEM). Lower content and higher surface energy dies were in favor of the copolymer to enrich on the PP surface. PPw-g-PMMA with low PMMA graft density, long length of PMMA was distributed in PP with smaller phase domains and concentration gradient, especially at lower loadings in blends, which favored its selective enrichment on the surface of PP. The modified material exhibited excellent solvent-resistance. The results indicated that PPw-g-PMMA can transfer to the surface of blends and effectively increase the hydrophilicity of PP, which offer a convenient technique to functionalize the surface of polymers with lasting-effectiveness compared with modification by homopolymers.