This time, the development of membrane formation and membrane application processes will be discussed. During the biotechnology boom of the 1980s, we developed processes that combined enzyme reactions and membranes, and ethanol fermentation and membranes. Ethanol selective permeation membrane is necessary for ethanol fermentation membrane reactor, and membrane distillation method, 1–(Trimethylsilyl)–1–propyne (PTMSP) membrane and silicalite membrane were investigated. In particular, excellent results were obtained with the silicalite membrane. In the 1980s, when the integrated circuit industry was activated and a large amount of trihalomethanes were used, environmental pollution became a problem. Therefore, we developed a separation membrane for trihalomethanes. The developed membrane is a membrane in which a polymer that selectively permeates trihalomethanes is grafted in the pores of a porous support membrane. It was named plasma filling polymerized membrane and a membrane with a new concept. This method later led to a series of membranes that became gate membranes by changing the graft polymer to temperature–responsive polymer of N–Isopropylacrylamide (NIPAM), molecular recognition crown ether–introduced polymer, ethanol recognition polymer, and so on. Furthermore, we introduced this technique to porous microcapsules and developed environment–responsive microcapsules. In principle, particle classification is possible with microfiltration membranes, but in practice even particles smaller than the membrane pores do not permeate the membrane. This is thought to be due to the formation of a particle cake layer, but it was technically difficult to prevent the formation of the cake layer. We took on this challenge and enabled particle classification while preventing cake layer formation. The operating conditions that prevent cake layer formation were also quantified. The final research topic is the development of anti–fouling membranes. Based on research in the biomaterials field, anti–fouling polymers, such as betaine–based polycarboxymethyl betaine (PCMB) and polymethoxyethyl acrylate (PMEA) are used. Membranes were prepared by dynamic membrane method, plasma graft polymerization method, Atom Transfer Radical Polymerization (ATRP) method and Nonsolvent Induced Phase Separation (NIPS) method. The membrane with anti-fouling performance could be created. We also calculated the membrane permeation behavior by molecular dynamics.
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