摘要:
A process for producing a polyethylene material for use in products requiring high mechanical strength and high elastic modulus is disclosed. The process involves the use of a specific class of particulate polyethylenes having an intrinsic viscosity of 5-50 dl/g in decalin at 135.degree. C. and the steps of compression molding, solvent immersing, solid-phase extruding or rolling and finally drawing the material in that order.
摘要:
A process for producing polyethylene materials is disclosed in which particulate polyethylene is drawn at lower temperatures than its melting point, the polymer having an intrinsic viscosity of 5-50 dl/g at 135.degree. C. in decalin and resulting from the polymerization of ethylene at temperatures below the above melting point and with use of a selected catalyst. The polyethylene materials excel in mechanical strength and elastic modulus.
摘要:
An anisotropy-free laminate having much higher strength and stiffness as compared with conventional articles is here disclosed which can be prepared by laminating an orientated ultra-high-molecular-weight polyethylene onto an adhesive layer obtained by modifying an olefin polymer with an unsaturated carboxylic acid and/or its derivative at a temperature lower than the melting point of the orientated ultra-high-molecular-weight polyethylene. The anisotropy-free material having high strength and high stiffness of the present invention can be substituted for various materials such as metals, lumber and FRP, and is also lightweight and excellent in water resistance.
摘要:
The present invention provides a split polyethylene stretched material having a tensile strength of at least 0.7 GPa when twisted in the range of 50-500 times/m, which material is produced by subjecting a polyethylene having an intrinsic viscosity of 5-50 dl/g as measured at 135.degree. C. in decalin, i.e. an ultra-high-molecular-weight polyethylene to stretching and then subjecting the stretched polyethylene to splitting, as well as a process for producing said material. The split polyethylene stretched material according to the present invention has a large surface area and accordingly can be easily laminated to other materials, and has a high strength and flexibility.
摘要:
A process is provided for the continuous production of a high-strength and high-modulus polyethylene material having excellent properties. According to the process, powder composed of ultra-high-molecular-weight polyethylene powder as a principal component is subjected to compression molding, rolling and stretching. The polyethylene powder has an intrinsic viscosity of 5-50 dl/g as measured at 135.degree. C. in decalin. The compression molding is carried out by feeding the polyethylene powder between endless belts arranged in an opposing up-and-down relation, and conveying the polyethylene powder while holding the same between the endless belts and at the same time, continuously compression molding the polyethylene powder at a temperature lower than its melting point by a compressing means provided inside of the endless belts. In at least one of the compression molding step and rolling step, an olefin polymer having a molecular weight lower than the polyolefin polymer is concurrently processed.
摘要:
A thermoplastic elastomer composition prepared by partially crosslinking a composition comprising the following components (A), (B) and (C):(A) 30-70 parts by weight of an ethylene/.alpha.-olefin copolymer prepared by copolymerizing ethylene and an .alpha.-olefin having 3 to 12 carbon atoms in the presence of a catalyst comprising a solid component and an organoaluminum compound which solid component contains at least magnesium and titanium, said ethylene/.alpha.-olefin copolymer having the following properties (I) to (IV):______________________________________ (I) Melt index 0.01-100 g/10 min (II) Density 0.860-0.910 g/cm.sup.3 (III) Maximum peak not lower than 100.degree. C. temperature as measured according to a differential scanning calorimetry (DSC) (IV) Insolubles in boiling not less than 10 wt. % n-hexane ______________________________________ (B) 70-30 parts by weight of a propylene polymer; and(C) 70-200 parts by weight, based on 100 parts by weight of the components (A) and (B), of an ethylene/.alpha.-olefin copolymer rubber.
摘要:
A thermoplastic elastomer composition prepared by partially crosslinking a composition comprising the following components (A), (B), (C) and (D):(A) 10-40% by weight of an ethylene/.alpha.-olefin copolymer prepared by copolymerizing ethylene and an .alpha.-olefin having 3 to 12 carbon atoms in the presence of a catalyst comprising a solid component and an organoaluminum compound which solid component contains at least magnesium and titanium, said ethylene/.alpha.-olefin copolymer having the following properties (I) to (IV):(I) Melt index: 0.01-50 g/10 min(II) Density: 0.860-0.910 g/cm.sup.3(III) Maximum peak temperature as measured according to a differential scanning calorimetry (DSC): not lower than 100.degree. C.(IV) Insolubles in boiling n-hexane: not less than 10 wt. %(B) 15-35% by weight of a propylene polymer;(C) 10-40% by weight of an ethylene/.alpha.-olefin copolymer rubber; and(D) 10-40% by weight of an ethylene/unsaturated monocarboxylic acid ester copolymer in which the carboxylate unit content is 2-10 mol %.
摘要:
A method for producing foamed thermoplastic resin profiles with an outer skin layer of increased hardness and an inner foam structure which may be used in place of wooden articles. The outer skin has a smooth surface and a good appearance, and the inner portion enclosed by the skin has a uniform foam structure. Also, with this method an improved foaming efficiency can be obtained. The method comprises a step of melting and kneading a mixture consisting of a thermoplastic resin and a foaming agent without causing the gasification of the foaming agent, a step of heating the melted and kneaded mixture obtained in the previous step to cause the gasification of the foaming agent without agitating the mixture and under a pressure sufficient to supress the substantial foaming of the mixture, thereby forming an expandable melted resin mixture containing microbubbles which are prevented from gathering and uniting, and a third step of causing the melted resin obtained in the previous step to expand while cooling the resin by leading the resin to a foaming die under low temperature and low pressure conditions.
摘要:
The present invention provides a prepreg obtained by stretching a material including, as a main component, an ultra-high-molecular-weight polyethylene having an intrinsic viscosity of 5-50 dl/g as measured at 135.degree. C. in decalin, to a total draw ratio of at least 20, subjecting the resulting stretched polyethylene material to a splitting treatment, and impregnating the resulting material with a thermosetting resin, and a process for producing said prepreg. The split stretched polyethylene material has improved adhesion to the impregnant resin and can be used as a good base material for prepreg.
摘要:
The present invention provides a prepreg obtained by stretching a material including, as a main component, an ultra-high-molecular-weight polyethylene having an intrinsic viscosity of 5-50 dl/g as measured at 135.degree. C. in decalin, to a total draw ratio of at least 20, subjecting the resulting stretched polyethylene material to a splitting treatment, and impregnating the resulting material with a thermosetting resin. The split stretched polyethylene material has improved adhesion to the impregnant resin and can be used as a good base material for prepreg.