Polypropylene surface photografting onto

Choice of sensitizer is related to the base polymer properties. Besides triplet sensitizers, dyes(4, 5), metal salts(11, 12), and radical initiators(7, 11, 12) have been used in photografting. These sensitizers other than triplet sensitizers are, however, not capable of initiating surface photografting onto polyolefins. Although benzoin isopropyl ether has been used for photografting of polypropylene, the reaction conditions seem to be in favor of deep grafting(12). 

Photochemical grafting of monomers/molecules onto substrates continues to show interest in terms of improving property requirements. Dyes have been effectively photografted onto polypropylene and nylon 6 films using 1,2-diphenyl-2,2-dimethoxyethanone while methacrylic acid and acrylamide have been successfully photografted onto polypropylene sheets using benzophenone as a sensitiser in order to modify the surface of the polymer from a hydrophobic to a hydrophilic one. A styrene-2,2,6,6-tetramethyl-4-piperidinyl... 

This paper presents photografting as a surface modification method to provide permanent wettability improvement to deep-groove polypropylene (PP) fibers. We also describe approaches to evaluate the wettability of these fibers and the wicking performance of fiber bundles when polyacrylamide (PAAm) was grafted onto the fibers. In this study, the concentration of the monomer and the UV-exposure time were altered to examine the effects of those variables on fiber hydrophilicity. Results showed lower water contact angle and improved wicking capacity upon modification with PAAm. 

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