| As we known, due to its special structures, amphiphilic copolymer possesses much particular specificity, such as in selective solvents, in bulk and at the surface. At present, many hot topics related amphiphilic copolymer have been drawing great attentions focused on nano-materials (L-B membrane), liquid crystal (especially polymeric liquid crystal with pendant segment), biology materials, medicine carrier and separate membrane, polymeric alloy (blender), flocculants on oil industry and adhesives on chemical industry, emulsifier and dispersant on emulsion and dispersion polymerization, and so on. Therefore, amphiphilic copolymer has been the main objective on chemistry, medicine, physics, and life science related. At present, the research on surface properties of amphiphilic copolymer mainly focused on the ability of amphiphilic copolymer to rearrange surface structure in response to atmosphere and self-assemble into micro-porous materials. However, the surface properties, surface composition and morphology of amphiphilic graft copolymer film under the solvent and mixing solvent induced have received little attention. Particularly, utilizing the solvent induced make the surface wettability transformate from the hydrophobic to hydrophilic, the part of which has original creation. By radical solution co-polymerization of macromonomer NPEO-MA with different monomers, amphiphilic graft copolymer polystyrene- graft-nonylphenoxy-poly(ethylene oxide) (PS-g-NPEO) and poly (methyl methacrylate)-graft-nonylphenoxy-poly(ethyleneoxide)(PMMA-g- NPEO) have been synthesized. By precoating evaporating method, amphiphilic graft copolymer film was prepared from different solvents or mixing solvents on PET or BOPP matrix. By means of IR, UV, NMR, SEM, XPS and ATR-FTIR, CA, the structure of amphiphilic graft copolymer and its surface morphology, surface composition and surface wettability were investigated respectively, which expatiate on the relationship among the surface morphology, composition and surface properties, briefly. In PS-g-NPEO system, the formation of the regularly micro porous resulted from amphiphilic graft copolymer film in different condition. With the increasing of NPEO content, the micro porous of graft copolymer film increased and the wettability of polymer film became better. With the increasing of the solution concentration, the diameter of micro porous of graft copolymer films increased, which make the wettability of polymer film better in THF; while in toluene, the influence of the solution concentration on surface morphology was showed weakly, but the relationship of contact angle and concentration was opposite to that in THF, i.e., with the increasing of concentration, the wettability of amphiphilic graft copolymer film became worse. In the same solution concentration,the diameter of micro porous of polymer film in THF was bigger than that of in toluene and the hydrophilic composition in THF was less than that of in toluene. Adopting different matrix such as BOPP or PET, amphiphilic graft copolymer film present different surface properties. In low concentration, the surface of amphiphilic graft copolymer film was smooth on PET, and surface hydrophilic composition was less, which make its surface wettability worse, while on PET, possessing some micro porous and high hydrophilic composition on the surface make its surface wettability better; in high concentration, the influence of matrix on surface morphology, composition and wettability was showed weakly. When in different concentrations, the change trend on surface morphology, composition and wettability of different types amphiphilic graft copolymer (PS-g-MPEO and PS-g-NPEO) was almost same, whereas, the micro porous of graft copolymer (PS-g-NPEO) film was bigger, and surface wettability was better, correspondingly.In PMMA-g-NPEO systems,with the increasing of NPEO content, surface properties of copolymer film became better, particularly, when the bulk content of NPEO reached 38%, surface water contact was less 10o... |
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