Abstract:
Provided are a chloroprene rubber that is less adhesive to rolls and gives a vulcanized product superior in physical properties, a production method thereof, a chloroprene rubber composition and a vulcanized product thereof. A chloroprene rubber comprising a steroid skeleton-containing compound. The chloroprene rubber may contain a steroid skeleton-containing compound in an amount of 0.01 to 1 mass %. A vulcanized product is prepared by vulcanizing a composition containing the chloroprene rubber. The chloroprene rubber can be prepared, for example, by emulsion-polymerizing chloroprene alone or chloroprene and other monomers in combination in the presence of a rosin containing a steroid skeleton-containing compound.
Abstract:
Provided are: surface modification method for imparting slidability to surface of elastic body such as vulcanized rubber or thermoplastic elastomer without using expensive self-lubricating resin; surface-modified elastic body with polymer brush formed on its surface; and gasket for injector and injector formed of surface-modified elastic body. The surface modification method applies to surface of thermoplastic elastomer or vulcanized rubber. The surface modification method comprises the step of forming hydroxyl group on surface of to-be-modified object such as rubber so that water contact angle of the surface becomes 8 to 50 degrees smaller than original water contact angle in unmodified condition, the step of forming polymerization initiation site by subjecting the hydroxyl group to action of secondary or tertiary organic halide, and the step of growing polymer brush on the surface of to-be-modified object by subjecting monomer to radical polymerization at the polymerization initiation site acting as a point of initiation.
Abstract:
An object of the present invention is to provide a polychloroprene latex with improved rubber coagulability that gives a film superior in strength by dip molding, a polychloroprene latex composition, and a molded article. The polychloroprene latex is prepared by polymerization of 2-chloro-1,3-butadiene alone or by polymerization of raw monomers at least containing 2-chloro-1,3-butadiene and 2,3-dichloro1,3-butadiene and has a precipitation rate of 5 to 40%, as calculated according to Equation (I). In Equation (I), A is the mass (g) of the dry product, which is obtained by adding 50 ml of saturated aqueous solution of calcium hydroxide at 23° C. to 50 g of a latex having a solid matter concentration adjusted to 45 to 65 mass % at a liquid temperature of 23° C. over 2 minutes, filtering and collecting the generated precipitate with a 80-mesh wire mesh, and drying the precipitate at 110° C. for 3 hours; B is the mass of the latex before the dropwise addition (50 g); and C is the solid matter concentration (mass %) of the latex before the dropwise addition. Precipitation rate ( % ) = A B × C 100 × 100 ( I )
Abstract:
Provided are: surface modification method for imparting slidability to surface of elastic body such as vulcanized rubber or thermoplastic elastomer without using expensive self-lubricating resin; surface-modified elastic body with polymer brush formed on its surface; and gasket for injector and injector formed of surface-modified elastic body. The surface modification method applies to surface of thermoplastic elastomer or vulcanized rubber. The surface modification method comprises the step of forming hydroxyl group on surface of to-be-modified object such as rubber so that water contact angle of the surface becomes 8 to 50 degrees smaller than original water contact angle in unmodified condition, the step of forming polymerization initiation site by subjecting the hydroxyl group to action of secondary or tertiary organic halide, and the step of growing polymer brush on the surface of to-be-modified object by subjecting monomer to radical polymerization at the polymerization initiation site acting as a point of initiation.
Abstract:
Provided are: surface modification method for imparting slidability to surface of elastic body such as vulcanized rubber or thermoplastic elastomer without using expensive self-lubricating resin; surface-modified elastic body with polymer brush formed on its surface; and gasket for injector and injector formed of surface-modified elastic body. The surface modification method applies to surface of thermoplastic elastomer or vulcanized rubber. The surface modification method comprises the step of forming hydroxyl group on surface of to-be-modified object such as rubber so that water contact angle of the surface becomes 8 to 50 degrees smaller than original water contact angle in unmodified condition, the step of forming polymerization initiation site by subjecting the hydroxyl group to action of secondary or tertiary organic halide, and the step of growing polymer brush on the surface of to-be-modified object by subjecting monomer to radical polymerization at the polymerization initiation site acting as a point of initiation.
Abstract:
An object of the present invention is to provide a polychloroprene latex with improved rubber coagulability that gives a film superior in strength by dip molding, a polychloroprene latex composition, and a molded article. The polychloroprene latex is prepared by polymerization of 2-chloro-1,3-butadiene alone or by polymerization of raw monomers at least containing 2 -chloro-1,3-butadiene and 2,3-dichloro 1,3-butadiene and has a precipitation rate of 5 to 40%, as calculated according to Equation (I). In Equation (I), A is the mass (g) of the dry product, which is obtained by adding 50 ml of saturated aqueous solution of calcium hydroxide at 23° C. to 50 g of a latex having a solid matter concentration adjusted to 45 to 65 mass % at a liquid temperature of 23° C. over 2 minutes, filtering and collecting the generated precipitate with a 80 -mesh wire mesh, and drying the precipitate at 110° C. for 3 hours; B is the mass of the latex before the dropwise addition (50 g); and C is the solid matter concentration (mass %) of the latex before the dropwise addition. Precipitation rate ( % ) = A B × C 100 × 100 ( I )
Abstract:
Provided are a chloroprene rubber that is less adhesive to rolls and gives a vulcanized product superior in physical properties, a production method thereof, a chloroprene rubber composition and a vulcanized product thereof. A chloroprene rubber comprising a steroid skeleton-containing compound. The chloroprene rubber may contain a steroid skeleton-containing compound in an amount of 0.01 to 1 mass %. A vulcanized product is prepared by vulcanizing a composition containing the chloroprene rubber. The chloroprene rubber can be prepared, for example, by emulsion-polymerizing chloroprene alone or chloroprene and other monomers in combination in the presence of a rosin containing a steroid skeleton-containing compound.
Abstract:
Disclosed are systems and methods for producing a polymer dispersion based on polychloroprene, comprising steps of polymerizing chloroprene to polychloroprene, adding the polycholoprene dispersion to a stripper column, and removing chloroprene from the polychloroprene dispersion.