Polyvinyl alcohol films
Реферат: Compositions comprise a polyvinyl alcohol having a melting point of 375 DEG to 425 DEG F., a residual ester content, calculated as polyvinyl ester, of 25 to 40% by weight, and a 4% aqueous solution viscosity of 4 to 45 centipoises at 20 DEG C., 10 to 40 parts by weight per 100 parts of polyvinyl alcohol of a plasticizer which is completely compatible and substantially non-volatile at the melting temperature of the polyvinyl alcohol, and not more than 0.5 weight per cent of moisture. The polyvinyl alcohol preferably contains less than 1.0 weight per cent of ash, or is neutralized with phosphoric, citric, malic or tartaric acid or an alkali metal phosphate. Specified plasticizers are glycerol, ethylene glycol, sorbitol, condensates of ethylene oxide with phenols, furfuryl alcohol, tetrahydrofurfuryl alcohol and urea, tributyl phosphate, tributoxyethyl phosphate, dimethylformamide, N-hydroxyethyl formamide and trimethylolpropane. The compositions may also contain antioxidants, e.g. butylated hydroxyanisole, butylated hydroxytoluene, sodium benzoate, calcium stearate, lactose and salts of copper, nickel, cobalt and tin; and lubricants and antisticking agents. The compositions may be used to form polyvinyl alcohol tubes and sheets by blow extrusion. Examples describe compositions comprising partially hydrolsed polyvinyl acetate and (1) to (3) a phenol/ethylene oxide condensate, (4) a phenol/ethylene oxide condensate and a slip agent, (5) a phenol/ethylene oxide condensate, polyvinyl alcohol, glycerol and butylated hydroxytoluene, (6) a phenol/ethylene oxide condensate, triethylene glycol and butylated hydroxytoluene, (7) ethylene oxide condensates with phenol and sorbitol and butylated hydroxytoluene, (8) a phenol/ethylene oxide condensate and polyethylene glycol, and (9) trimethylol propane and butylated hydroxytoluene.
Polyvinyl alcohol-based resin composition and melt-molded article using said composition
Номер патента: US20230174765A1. Автор: Masahiko Taniguchi,Satoshi IKUBO. Владелец: Mitsubishi Chemical Corp. Дата публикации: 2023-06-08.