Effect of the pore surface modification of an inorganic substrate on the plasma-grafting behavior of pore-filling-type organic/inorganic composite membranes

• Published in: Journal of polymer science. Part A, Polymer chemistry Polymer chemistry, 2006-01, Vol.44 (2), p.846-856
• Main Authors: Kai, Teruhiko, Suma, Yasunori, Ono, Shuichiro, Yamaguchi, Takeo, Nakao, Shin-ichi
• Format: Article
• Language: English
• Subjects: Applied sciences; composites; Exact sciences and technology; Exchange resins and membranes; Forms of application and semi-finished materials; graft copolymers; organic/inorganic composite membranes; plasma polymerization; Polymer industry, paints, wood; pore-filling-type membranes; Technology of polymers
• ISSN: 0887-624X; 1099-0518
• DOI: 10.1002/pola.21168

We have investigated the effect of the surface state and surface treatment of the pores of an inorganic substrate on the plasma‐grafting behavior of pore‐filling‐type organic/inorganic composite membranes. Shirasu porous glass (SPG) was used as the inorganic substrate, and methyl acrylate was used as the grafting monomer. The grafting rate increased as the density of silanol on the SPG substrate increased. This result suggests that radicals are generated mainly at the silanol groups on the pore surface by plasma irradiation. The SPG substrates were treated with silane coupling agents used to control the mass of organic material bonded to the pore surface. The thickness of the grafted layer became thinner as the mass of organic material bonded to the pore surface of SPG increased. This decrease in the thickness of the grafted layer could be explained by the decrease in the penetration depth of vacuum ultraviolet rays contained in plasma having a wavelength of less than 160 nm that generated radicals in the pores of the substrate. The thickness of the grafted layer inside the SPG substrates could be controlled through the control of the mass of organic material bonded to the pore surface of the SPG substrate. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 846–856, 2006 The effect of the surface treatment of a porous glass substrate on the plasma‐grafting behavior of pore‐filling‐type organic/inorganic composite membranes was examined. The thickness of a grafted layer with a porous glass substrate was greater than that with a polyethylene substrate. This difference in the grafted layer thickness could be explained by the difference in the penetration depth of vacuum ultraviolet rays contained in plasma having a wavelength of less than 160 nm that generated radicals in the pores of the substrate. The thickness of a grafted layer with a silylated porous glass substrate was between the thicknesses of grafted layers with porous polyethylene and untreated porous glass.