Mitsubishi Rayon

Mitsubishi Rayon Co. has developed an acrylic asbestos replacement fiber with a tensile strength of almost 600 MPa (87,000 psi) (78,79). In addition, patents for acrylic asbestos replacement fibers have been obtained by Asahi (80), Wuestefeld (81), REDCO (82), and Hoechst (83). The Hoechst fiber, marketed under the trade name Dolanit (originally Dolan 10), is offered in two forms as shown in Table 4. 

Aloisture Absorbent Synthetic Paper. Processes for making a water absorbent synthetic paper with dimensional stabihty have been developed by several companies. In a process developed by Mitsubishi Rayon, acrylic fiber is insolubilized by hydra2ine and then hydroly2ed with sodium hydroxide. The paper, formed from 100 parts fiber and 200 parts pulp, has a water absorption 28 times its own weight (96). Processes for making hygroscopic fibers have also been reported in the patent Hterature. These fibers are used in moisture absorbing nonwovens for sanitary napkins, filters, and diapers. 

The formaldehyde approach is stiU used by Futamura Chemical (Japan). They make spun-laid viscose nonwovens where the hydroxymethylceUulose xanthate derivative formed from formaldehyde ia the spia bath allows the fibers to bond after layiag. This process was originally developed by Mitsubishi Rayon (30), who later found that the derivative was thermoplastic, and the web could be calender-bonded (120°C) prior to regeneration (31). 

Until 1982, almost all methyl methacrylate produced woddwide was derived from the acetone cyanohydrin (C-3) process. In 1982, Nippon Shokubai Kagaku Kogyo Company introduced an isobutylene-based (C-4) process, which was quickly followed by Mitsubishi Rayon Company in 1983 (66). Japan Methacryhc Monomer Company, a joint venture of Nippon Shokubai and Sumitomo Chemical Company, introduced a C-4-based plant in 1984 (67). Isobutylene processes are less economically attractive in the United States where isobutylene finds use in the synthesis of methyl /i / butyl ether, a pollution-reducing gasoline additive. BASF began operation of an ethylene-based (C-2) plant in Ludwigshafen, Germany, in 1990, but favorable economics appear to be limited to conditions unique to that site. 

Isobutjiene [115-11-7] or tert-huty alcohol can be converted to methacrylic acid in a two-stage, gas-phase oxidation process via methacrolein as an intermediate. The alcohol and isobutjiene may be used interchangeably in the processes since tert-huty alcohol [75-65-0] readily dehydrates to yield isobutjiene under the reaction conditions in the initial oxidation. Variations of this process have been commercialized by Mitsubishi Rayon and by a joint venture of Sumitomo and Nippon Shokubai. Nippon Kayaku, Mitsui Toatsu, and others have also been active in isobutjiene oxidation research. 

Jptt Kokai Tokkyo Koho JP 47023294 (June 29, 1972), M. Yamaguchi and T. Okano (to Mitsubishi Rayon Co., Ltd.). 

Data from the following technical data sheets PAN fibers Amoco Performance Products, Asahi Kasei, BASE Stmctural Materials, Courtaulds-Grafil, Hercules, Mitsubishi Rayon, Toho Beslon, Toray Pitch fibers Amoco Performance Products, Mitsubishi Kasei, Tonen Corp. 

Producers of PAN-based carbon fiber include Toray, Toho Beslon, Mitsubishi Rayon, and Asahi Kasai Carbon in Japan Hercules, Amoco Performance Products, BASE Stmctural Materials, Eortafil (Akzo), and Mitsubishi Rayon in the United States and Akzo, Sigri, and Soficar in Europe. Primary suppHers of high performance pitch-based carbon fibers include Amoco Performance Products, Mitsubishi Kasai, and Tonen Corp. 

ICI Acrylics believes that greater cooperation between companies and a revised approach to life cycle analysis are the keys to the industry s future environmental sustainability. The company has invested over 2m pounds sterling in an on-going monomer recovery project, which encompasses a joint research programme with Mitsubishi Rayon. The project focuses on increasing the efficiency of acrylic depolymerisation and overcoming technical issues such as its use in recycling flame retardant acrylics. ICI ACRYLICS... 

ICI Acrylics activities in chemical recycling of acrylics is discussed. The company is offering a take-back service for scrap PMMA which it chemically recycles back into MMA. Together with Mitsubishi Rayon, it has established a joint venture to develop more efficient depolymerisation... 

---