Thermoplastic materials and article made therefrom
AssigneeNippon Zeon Co., Ltd.
InventorsNobukazu Takahashi, Teiji Kohara, Tadao Natsuume
Life of this patent
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Abstract
The present invention provides a thermoplastic composition excellent in heat resistance and water resistance which comprises a thermoplastic saturated norbornene polymer which has a number-average molecular weight (Mn) of 50,000-500,000 and a weight-average molecular weight (Mw) of 100,000-2,000,000 which are measured by high performance liquid chromatography, and a molecular weight distribution (Mw/Mn) of 2.2 or more, and a volatile content of at most 0.3% by weight. The composition is suitable for optical materials, electroconductive composite materials and optical recording media.
Claims19
A film or sheet article having a tensile strength of at least 800 kg/cm.sup.2 and substantially free from microvoids, which is obtained by molding a thermoplastic composition comprising a thermoplastic saturated norbornene polymer which has a number-average molecular weight (Mn) of 50,000 to 500,000 and a weight-average molecular weight (Mw) of 100,000 to 2,000,000 which are measured by high performance liquid chromatography, and a molecular weight distribution (Mw/Mn) of at least 2.2, wherein said thermoplastic saturated norbornene polymer has a maximum volatile content of 0.1% by weight.
A thermoplastic composition for films or sheets which is obtained by pelletizing, by melt extrusion, a thermoplastic composition comprising a thermoplastic saturated norbornene polymer which has a number-average molecular weight (Mn) of 50,000 to 500,000 and a weight-average molecular weight (Mw) of 100,000 to 2,000,000 which are measured by high performance liquid chromatography, and a molecular weight distribution (Mw/Mn) of at least 2.2, and a maximum volatile content of 0.3% by weight, and drying the obtained pellets at a maximum temperature of 5.degree. C. below the glass transition temperature (Tg) of said polymer.
A process for producing a film or sheet article having a tensile strength of 800 kg/cm.sup.2 or more and free from microvoids;
- said process comprising steps of
- (1) pelletizing by melt-extrusion a thermoplastic composition comprising thermoplastic saturated norbornene polymer having a number average molecular weight (Mn) of 50,000 to 500,000 and a weight-average molecular weight (Mw) of 100,000 to 2,000,000 when measured by high performance liquid chromatography, and a molecular weight distribution (Mw/Mn) of 2.2 or more;
- said composition having a volatile content of at most 0.3% by weight,
- (2) drying thus pelletized composition at a temperature lower by at least 5.degree. C. than the glass transition temperature (Tg) of said polymer, and
- (3) forming said film or sheet article from thus dried pellets.
Dependencies are inferred from the claim text.