Abstract: A production method for an optical transmission element, wherein a cylindrical transparent resin is used as a core wire, a monomer becoming a polymer different in refractive index from the core wire after polymerized or a mixture of a monomer and a polymer is bonded to the outer periphery of the core wire and the monomer is diffused from the outer periphery of the core wire to thereby form the monomer inside the core wire at a proper concentration distribution, and then the monomer is further polymerized to the core wire to provide a distribution layer having different refractive indexes from the center toward the outer periphery, whereby it is possible to provide a graded index type optical transmission element at low costs with a simple facility.

Abstract: A production method for an optical transmission element (1), wherein a cylindrical transparent resin is used as a core wire, a monomer becoming a polymer different in refractive index from the core wire after polymerized or a mixture of a monomer and a polymer (2) is bonded to the outer periphery of the core wire and the monomer is diffused from the outer periphery of the core wire to thereby form the monomer inside the core wire at a proper concentration distribution, and then the monomer is further polymerized to the core wire to provide a distribution layer having different refractive indexes from the center toward the outer periphery, whereby it is possible to provide a graded index type optical transmission element at low costs with a simple facility.

Abstract: Disclosed is a resin composition comprising a copolymer [I] having a number average molecular weight of at least 15,000, which comprises at least 30 mole % of the following recurring units [A]: ##STR1## and a compound [II] having a number average molecular weight of at least 1,000, which is comprised of perfluoroalkylether recurring units [D]. This resin composition is used as a cladding of a core-clad optical fiber.

Abstract: An acrylonitrile polymer film is disclosed which film comprising a polymer containing higher than 80% by weight of acrylonitrile units, having higher than 300,000 of weight average molecular weight, and having molar fraction Ne for the segment of polymerization initiator bonded to the terminal of the polymer satisfying the following equation:Mw.times.Ne.ltoreq.

Abstract: Disclosed is a resin composition comprising a copolymer [I] having a number average molecular weight of at least 15,000, which comprises at least 30 mole % of the following recurring units [A]: ##STR1## and a compound [II] having a number average molecular weight of at least 1,000, which is comprised of perfluoroalkylether recurring units [D]. This resin composition is used as a cladding of a core-clad optical fiber.

Abstract: Disclosed is method for producing a rubber modified thermoplastic reins which comprises carrying out all or a part of the following setps (I) - (VI):(I) a step of mixing the following (A), (B), (C) and thermoplastic resin (2):(A) a latex of graft rubber polymer (1),(B) an organic agent which is capable of dissolving thermoplastic resin (2) and has a solubility in water of 5% by weight or less at a temperature at which (A), (B), (C) and thermoplastic resin (2) are mixed, amount of the organic agent being 10-600% by weight of polymer (4) which is the sum of graft rubber polymer (1) and thermoplastic resin (2) and(C) a water soluble agent capable of coagulating latex (A), amount of this agent being 10% by weight or less of graft rubber polymer (1),(II) a step of separating and removing aqueous phase from a two-phase mixture obtained in the mixing step (I),(III) a step of mixing the mixture from which the aqueous phase has been removed at step (II) and the whole or a part of thermoplastic resin (3),(IV) a step of

Abstract: Disclosed herein is a particulate polymer prepared by the agglomeration of polymer particles contained in a polymer latex. The particulate polymer is composed of primary particles having particle sizes of at least 20 .mu.m and/or secondary particles formed by the agglomeration of at least some of the primary particles and is in the form of a compact mass substantially free of voids. The particulate polymer is prepared by coagulating the polymer latex in the presence of a coagulant and an organic liquid having low solubility in water. The particulate polymer has a high bulk specific gravity and contains few fine particles. It is thus easy to handle and allows the consumption of energy to be reduced in the drying step.

Abstract: A plastic core-plastic cladding optical fiber is described wherein the core is composed of a copolymer of a perfluorodioxole represented by the following formula: ##STR1## wherein R and R' independently represent F or CF.sub.3, with at least one other ethylenically unsaturated monomer substantially free of CH bonds and the copolymer has no first order transition temperature as determined by the differential scanning colorimetry (DSC) and has a second order transition temperature not lower than 100.degree. C. as determined by DSC.

Abstract: Emulsion polymerization type thermoplastic resin of high performance can be produced by the following methods: namely, a method which comprises removing an aqueous phase from a two-phase mixture comprising a latex of polymer (1) produced by emulsion polymerization, a water soluble agent (2) in an amount of 10% by weight or less of said polymer (1) which is capable of coagulating the latex of polymer (1) and an organic agent (3) in an amount of 0.1 to 6 times the weight of said polymer (1) which is capable of dissolving both an uncrosslinked polymer contained in said polymer (1) and thermoplastic polymer (4) mentioned hereinbelow and has a solubility in water of 5% by weight or less at 25.degree. C.

Abstract: A method for coagulation of a polymer latex by feeding the polymer latex to an extruder having a base plate and a plurality of fine tubes fixed to said base plate and extending therefrom, said fine tubes being mutually spaced by at least 1 mm and protruding from said base plate by at least 3 mm, and discharging said polymer latex through said fine tubes into a coagulation solution to coagulate the latex.

Abstract: Disclosed is a method for producing a rubber modified thermoplastic resin which comprises carrying out all or a part of the following steps (I)-(VI):(I) a setp of mixing the following (A), (B), (C) and thermoplastic resin (2):(A) a latex of gfart rubber polymer (1),(B) an organic agent which is capable of dissolving thermoplastic resin (2) and has a solubility in water of 5% by weight or less t a temperature at which (A), (B), (C) and thermoplastic resin (2) are mixed, amount of the organic agent being 10-600% by weight of polymer (4) which is the sum of graft rubber polymer (1) and thermoplastic resin (2) and(C) a warer soluble agent capable of coagulating latex (A), amount of this agent being 10% by weight or less of graft rubber polymer (1),(II) a step of separating and removing aqueous phase from a two-phase mixture obtained in the mixing step (I),(III) a step of mixing the mixture from which the aqueous phase hsa been removed at step (II) and the whole or a part of thermoplastic resin (3),(IV) a step of

Abstract: Disclosed herein is a particulate polymer prepared by the agglomeration of polymer particles contained in a polymer latex. The particulate polymer is composed of primary particles having particle sizes of at least 20 .mu.m and/or secondary particles formed by the agglomeration of at least some of the primary particles and is in the form of a compact mass substantially free of voids. The particulate polymer is prepared by coagulating the polymer latex in the presence of a coagulant and an organic liquid having low solubility in water. The particulate polymer has a high bulk specific gravity and contains few fine particles. It is thus easy to handle and allows the consumption of energy to be reduced in the drying step.

Abstract: A spinning solution for acrylonitrile polymers is disclosed, which has a viscosity of 30 to 520 poises (at 50.degree. C.) and which comprises an acrylonitrile polymer having a reduced viscosity of not less than 4.0, a solvent, and water, wherein the water concentration and the polymer concentration fall within the range in the drawing surrounded by straight lines connecting point A (1 wt % and 30 wt % respectively), point B (1 wt % and 10 wt % respectively), and point C (10 wt % and 10 wt % respectively). The spinning solution exhibits satisfactory spinnability in spite of its high polymer concentration and provides void-free acrylonitrile fibers having a highly circular cross-section and excellent mechanical strength.

Abstract: An electrostatic recording material comprising a substrate treated for low electric resistance and a dielectric layer formed on the substrate and composed of a composition comprising an insulating resin having a volume specific resistance of at least 10.sup.12 .OMEGA.cm and a powder of an acrylonitrile-type polymer having a copolymerized acrylonitrile content of at least 95% by weight and containing substantially no ionic groups, said powder having a volume average particle size of from 1.5 to 4 .mu.m and a content of particles having a size exceeding 8 .mu.m as measured by a particle size distribution measuring apparatus, being at most 0.02% by number.

Abstract: Apparatus for coagulation of a polymer latex by feeding the polymer latex to an extruder having a base plate and a plurality of fine tubes fixed to said base plate and extending therefrom, said fine tubes being mutually spaced by at least 1 mm and protruding from said base plate by at least 3 mm, and discharging said polymer latex through said fine tubes into coagulation solution to coagulate the latex and an extruder used for carrying out said method.

Abstract: This invention provides a method and an apparatus for controlling a polymerization reaction. The temperature difference between a target temperature, calculated from the degradation rate of a polymerization initiator, which varies as a function of temperature, and a polymerization reactor temperature is calculated. The difference in polymerization rate between a target polymerization rate previously set and a polymerization rate calculated from a measured heat release value at a certain time in the polymerization process is calculated. The temperature inside the reactor is finely adjusted on the basis of the temperature difference and the difference in polymerization rate.

Abstract: The invention relates to a process for producing a powder of a cationic polymer by spreading on a moveable carrier a layer of an aqueous solution of a vinyl monomer, carrying out continuous polymerization followed by peeling off hydrous polymer from the carrier in a hot state, and cutting said hydrous polymer in a hot state by a shearing stress.

Abstract: Disclosed is a method for producing a rubber modified thermoplastic resin excellent in surface appearance and various properties and high in commercial values which comprises removing an aqueous phase from a two-phase mixture comprises a graft rubber polymer latex (1) obtained by graft polymerization of vinyl monomer on a rubber latex, a thermoplastic resin (2) and an organic agent in an amount of 0.2 to 6 times the weight of all the polymers (3) which is capable of dissolving said thermoplastic resin (2) and has a solubility in water of 5 to 50% by weight at 25.degree. C. and then removing said organic agent and remaining water from the remaining organic phase by a thermal means.

Abstract: Disclosed is a method for producing a rubber modified thermoplastic resin excellent in surface appearance and various properties and high in commercial values which comprises removing an aqueous phase from a two-phase mixture comprising a graft rubber polymer latex (1) obtained by graft polymerization of vinyl monomer on a rubber latex, a thermoplastic resin (2), an organic agent in an amount of 0.1 to 6 times the weight of all the polymers (3) which is capable of dissolving said thermoplastic resin (2) and has a solubility in water of 5% by weight or less at 25.degree. C. and a water soluble agent in an amount of 10% by weight or less of said graft rubber polymer which can coagulate said latex and then removing said organic agent and remaining water from the remaining organic phase by a thermal means.

Abstract: There is disclosed a method for treating an emulsified latex which comprises discharging an emulsified latex containing particles of 1 .mu.m or less in diameter into a coagulation solution from fine tubes which satisfy L/D.gtoreq.0.065 Re (L: length of fine tube, and D: equivalent diameter of fine tube and Re: Reynolds number) at a Reynolds number of 300 or less to coagulate the latex and washing and drying the coagulated latex to obtain a particulate of high bulk specific gravity containing substantially neither fine powders nor coarse particles or a pellet-like product.