Characteristics of permeation and separation for aqueous ethanol solutions through methyl methacrylate-dimethylsiloxane graft copolymer membranes

✍ Scribed by Takashi Miyata; Toru Takagi; Takeshi Kadota; Tadashi Uragami

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 710 KB
• Volume: 196
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.1995.021960420

✦ Synopsis

Poly(methy1 methacrylate) with oligodimethylsiloxane grafts (MMA-g-DMS) was prepared by copolymerization of a dimethylsiloxane (DMS) macromonomer with methyl methacrylate (MMA). Two glass transition temperatures (T,) were observed at about 120°C and -127 "C in all graft copolymer membranes. Transmission electron micrographs demonstrate that the MMAg-DMS membranes show microphase separation. When an aqueous solution of 10 wt.-Vo ethanol was applied to permeations through the MMA-g-DMS membranes by pervaporation, the ethanol concentration in the permeate and the permeation rate increased drastically with the DMS content in the copolymer. Especially, while at a DMS content of less than 40 mol-Vo preferentially water permeates from an aqueous solution of 10 wt.-Yo ethanol, the membranes with more than about 40 mol-Yo of DMS show ethanol-permselectivity. The relationship between the microphaseseparated structures and the permeation characteristics for an aqueous ethanol solution is discussed.