Application Of Maleic Anhydride Copolymer Derivatives In The Hydrophilic Modification Of Material Surfaces

Hydrophobic surfaces with low surface energy cause various problems such as dyeing,printing,painting,biofouling and fogging.Therefore,the hydrophilic modification of material surfaces attracts wide attention.In this thesis,the hydrophilic modification of polyethylene terephthalate（PET）and polypropylene（PP）nonwoven surfaces and anti-fogging modification of glass surfaces based on maleic anhydride copolymers and their derivatives are investigated as follows:（1）Commercially available isobutylene-maleic anhydride copolymer（PIBMA）and styrene-maleic anhydride copolymer（PSMA）prepared by self-stabilized precipitation polymerization and its esterification product PSMA-g-C₈H₁₇OH were used to modify PET and PP nonwoven fabrics by“impregnation-high temperature cross-linking”in organic and aqueous solution systems,respectively.Scanning electron microscopy（SEM）and weight gain rate tests demonstrated the formation of a polymeric coating layer on the surfaces of PET and PP nonwoven fibers.Atomic force microscopy（AFM）was utilized to determine the thickness of the coating layer,which was339 and 254 nm for PET and PP nonwoven fibers modified with 1 wt%PSMA alkali hydrolysis solution,respectively.PSMA alkaline hydrolysate in combination with adipic acid dihydrazide（ADH）was found to be the most effective in improving the surface hydrophilicity of PET and PP nonwoven fabrics by water contact angle and surface wetting tests.When the concentration of PSMA in aqueous solution was 1 wt%,the 60 s water contact angle reached 0 for PET nonwoven and 20°for PP nonwoven.Wetting tests showed that water droplets on the surface of PET nonwovens were completely wetted in 30 s,while 257 s were required for PP nonwovens.Durability tests showed that the polymer coatings of PET and PP nonwoven fabrics modified with 1 wt%PSMA alkaline hydrolysate and ADH aqueous solution were durable,with water contact angles being 26°and 68°on the surfaces of PET and PP nonwoven fabrics,respectively,after 12 h immersion in deionized water.Thermogravimetric analysis（TGA）showed no significant changes in the thermal properties of the modified PET and PP nonwoven fabrics.（2）2-Chloroethyl vinyl ether-maleic anhydride copolymer（PCVEM）and N,N-dimethyl-N-perfluorohexyl sulfonyl malondiamine(R_f)were prepared.By grafting R_fonto PCVEM,amphoteric macromolecular fluorosurfactants with different grafting percentages,denoted as PCVEM-0.125R_f,PCVEM-0.25R_fand PCVEM-0.5R_f,were obtained.The surface tension of their aqueous solutions was the lowest at p H=7.5,reaching about 18 m N/m.At this p H,coatings with different polymer concentrations and different number of layers were prepared on glass slide surfaces by layer-by-layer self-assembly（LBL）using PCVEM-R_fand polyethyleneimine（PEI）aqueous solutions.The water/oil contact angle test results showed that PCVEM-0.125R_f/PEI,PCVEM-0.25R_f/PEI and PCVEM-0.5R_f/PEI modified slides achieved water contact angles of 28°,38°and 46°,respectively.The rapid thermal fogging experiment showed that the PCVEM-0.125R_f/PEI-1.5-3modified slides had the best anti-fogging effect.In the self-cleaning test,the surface of PCVEM/PEI-modified slides was difficult to be cleaned after being contaminated by silicone oil,while the surface of PCVEM-R_f/PEI-modified slides had anti-fogging and self-cleaning properties.Antibacterial experiments showed that the surface of PCVEM-R_fmodified slides had more than 98%antibacterial rate against both E.coli and S.aureus.In this thesis,methods for the hydrophilic modification of PET,PP and glass surfaces based on maleic anhydride copolymers and derivatives have been established,which are significant for overcoming many problems caused by low surface energy hydrophobic surfaces.