摘要:
A polyethylene composition having excellent melt moldability which substantially comprises an ultrahigh-molecular-weight polyethylene having a molecular weight of, for example, at least about 1,650,000 and a low-molecular-weight to high-molecular-weight polyethylene having a molecular weight of, for example, about 1500 to about 360,000. The composition is produced by a multi-stage polymerization process involving a step of producing the ultrahigh-molecular-weight polyethylene and a step of producing the low-molecular-weight to high-molecular-weight polyethylene.
摘要:
A transparent, heat resistant polyester composition having improved mechanical strength is provided, which comprises (A) 20 to 80% by weight of a polyalkylene terephthalate predominantly comprising ethylene terephthalate and having an intrinsic viscosity of from 0.6 to 1.2 dl/g, and (B) 20 to 80% by weight of a bisphenol-A polycarbonate having an intrinsic viscosity of from 0.6 to 1.2 dl/g, the composition having an intrinsic viscosity of from 0.6 to 1.2 dl/g and a single glass transition temperature of from 80.degree. to 130.degree. C. A polyester laminate may be molded as comprising a layer of the polyester composition and a layer of alkylene terephthalate. The molded polyester laminate can take any form including films and containers.
摘要:
Biaxially oriented films from high molecular weight polyethylene are characterized by a gas permeable structure formed from random-arranged microfibrils. The films have coefficients of static friction and kinetic friction of not more than 1.0. The biaxially oriented films are further characterized by service smoothness as well as tensile (tangent) modulus and tensile strength. The films may be used for lamination, filter, or for packaging for moisture absorbers. The biaxially oriented films may be obtained by extracting a hydrocarbon plasticizer from a sheet formed from the high molecular weight polyethylene and a hydrocarbon plasticizer, stretching the resulting sheet to obtain an oriented film having a specific surface area of at least 70 m.sup.2 /g and a fibril structure, and heating the oriented film under a standard length constraint to reduce the oriented film in specific area by at least 20 m.sup.2 /g.
摘要:
Biaxially oriented films from high molecular weight polyethylene are characterized by a gas permeable structure formed from random-arranged microfibrils. The films have coefficients of static friction and kinetic friction of not more than 1.0. The biaxially oriented films are further characterized by service smoothness as well as tensile (tangent) modulus and tensile strength. The films may be used for lamination, filter, or for packaging for moisture absorbers. The biaxially oriented films may be obtained by extracting a hydrocarbon plasticizer from a sheet formed from the high molecular weight polyethylene and a hydrocarbon plasticizer, stretching the resulting sheet to obtain an oriented film having a specific surface area of at least 70 m.sup.2 /g and a fibril structure, and heating the oriented film under a standard length constraint to reduce the oriented film in specific area by at least 20 m.sup.2 /g.
摘要:
The present invention relates to a novel ethylene/pentene-1 copolymer whose molded film has a good balance between impact resistance and tear properties and high transparency, also is prominently reduced in a variation of the transparency even after subjected to a heat treatment, and further shows high blocking resistance, provided that the copolymer fulfills specific requisites. The invention also relates to a process for the preparation of the above-mentioned ethylene/pentene-1 copolymer and a formulation of the ethylene/pentene-1 copolymer composition using a stabilizer. According to the invention, there can be obtained an ethylene/pentene-1 copolymer composition which is excellent in heat stability in the molding stage, long-term heat stability and weatherability.
摘要:
In accordance with the present invention, there are provided polyester carbonate copolymers obtained by polymerization of a mixture of 20-80% by weight of an alkylene terephthalate oligomer [I] containing ethylene terephthalate as main structural units and having an intrinsic viscosity [.eta.], as measured at 25.degree. C. in o-chlorophenol, of less than 0.6 dl/g, and 20-80% by weight of a carbonate oligomer [II] containing 2,2-bis(4 -hydroxyphenyl)propane as main structural units and having an intrinsic viscosity [.eta.], as measured at 25.degree. C. in o-chlorophenol, of less than 0.6 dl/g, said copolymers having an intrinsic viscosity [.eta.], as measured at 25.degree. C. in o-chlorophenol, of 0.4-1.2 dl/g and a glass transition temperature (Tg) of 80.degree.-140.degree. C. with a single peak, and polyester resin compositions containing said copolymers, said resin composition being excellent in transparency, heat resistance and mechanical strength.
摘要:
Biaxially oriented films from high molecular weight polyethylene are characterized by a gas permeable structure formed from random-arranged microfibrils. The films have coefficients of static friction and kinetic friction of not more than 1.0. The biaxially oriented films are further characterized by service smoothness as well as tensile (tangent) modulus and tensile strength. The films may be used for lamination, filter, or for packaging for moisture absorbers. The biaxially oriented films may be obtained by extracting a hydrocarbon plasticizer from a sheet formed from the high molecular weight polyethylene and a hydrocarbon plasticizer, stretching the resulting sheet to obtain an oriented film having a specific surface area of at least 70 m.sup.2 /g and a fibril structure, and heating the oriented film under a standard length constraint to reduce the oriented film in specific area by at least 20 m.sup.2 /g.
摘要:
The biaxially oriented films of high molecular weight polyethylene is formed and its surface modified to provide a hydrophilic property to the resulting film. The film is prepared by melt-kneading the high molecular weight polyethylene with an ordinarily solid hydrocarbon plasticizer and a raw fabric sheet is formed from the resulting molten mixture. After the hydrocarbon plasticizer is extracted the resulting unstretched sheet is stretched under conditions providing a stretched film having a specific surface area of 70 m.sup.2 /g or more and a fibril structure. This stretched film is then heated under standard length constraint conditions to reduce the specific surface area of the stretched film by at least 20 m.sup.2 /g to obtain a biaxially oriented film of high molecular weight polyethylene. The surface of the film is thereafter subjected to surface modification by polymerizing a vinyl monomer having a hydrophilic group on the surface of the film whereby the film surface becomes hydrophilic, as measured by a contact angle of the film surface to a water drop at a level of not more than 90.degree.. The biaxially oriented films are further characterized by their excellent gas permeability, surface smoothness, tensile modulus and tensile strength.
摘要:
The present invention relates to a novel ethylene/pentene-1 copolymer whose molded film has a good balance between impact resistance and tear properties and high transparency, also is prominently reduced in a variation of the transparency even after subjected to a heat treatment, and further shows high blocking resistance, provided that the copolymer fulfills specific requisites. The invention also relates to a process for the preparation of the above-mentioned ethylene/pentene-1 copolymer and a formulation of the ethylene/pentene-1 copolymer composition using a stabilizer. According to the invention, there can be obtained an ethylene/pentene-1 copolymer composition which is excellent in heat stability in the molding stage, long-term heat stability and weatherability.
摘要:
In accordance with the present invention, there are provided cycloolefin type random copolymer compositions excellent in heat resistance, chemical resistance, rigidity, impact resistance, etc., which comprise(A) a cycloolefin type random copolymer containing an ethylene component and a cycloolefin component and having an intrinsic viscosity [.eta.] of 0.05-10 dl/g as measured at 135.degree. C. in decalin and a softening temperature (TMA) of not lower than 70.degree. C., and(B) one or more non-rigid copolymers selected from the group consisting of:(i) a cycloolefin type random copolymer containing an ethylene component, at least one other .alpha.-olefin component and a cycloolefin component and having an intrinsic viscosity [.eta.] of 0.01-10 dl/g as measured at 135.degree. C. in decalin and a softening temperature (TMA) of below 70.degree. C.,(ii) a non-crystalline to low crystalline .alpha.-olefin type elastomeric copolymer formed from at least two .alpha.-olefins,(iii) an .alpha.-olefin-diene type elastomeric copolymer formed from at least two .alpha.-olefins and at least one non-conjugated diene, and(iv) an aromatic vinyl type hydrocarbon-conjugated diene copolymer or a hydrogenated product thereof, and optionally(c) an inorganic filler or organic filler.