Biaxially oriented polyamide film
AssigneePhillips Petroleum Company
InventorsH. Wayne Hill, Jr., Jerry O. Reed
Life of this patent
Estimating the term…
Abstract
A biaxially-oriented amorphous polyamide film and the preparation thereof are described. The film exhibits good physical and optical properties. In a specific embodiment, the amorphous polyamide is a product of the polymerization of 2,2-bis(4-aminocyclohexyl)propane with a mixture of adipic acid and azelaic acid. The polymer is extruded as a sheet and biaxially oriented under described conditions to produce a clear film having a high glass transition temperature and improved elongation properties.
Claims19
An amorphous biaxially-stretched film having a thickness in the range of about 0.02 mm to about 0.3 mm formed from an essentially amorphous polyamide which is the product of the condensation polymerization of 2,2-bis(4-aminocyclohexyl)propane with a mixture of adipic acid and azelaic acid.
The film of claim 2 which is the product of biaxial orientation of an extruded sheet of an amorphous polyamide at a temperature within the range of from about 5.degree. C. to about 20.degree. C. above the glass transition temperature of the polyamide.
An amorphous biaxially-stretched film having a thickness in the range of about 0.02 mm to about 0.3 mm consisting essentially of an essentially amorphous polyamide which is the product of the condensation polymerization of 2,2-bis(4-aminocyclohexyl)propane with a mixture of adipic acid and azelaic acid.
A process for preparing an amorphous film having a glass transition temperature of from about 174.degree. C. to about 185.degree. C., a haze value of below about 1.5 percent and a tensile strength of at least about 100 MPa, the process comprising
- extruding an amorphous polyamide which is the product of the condensation polymerization of adipic acid, azelaic acid and 2,2-bis(4-aminocyclohexyl)propane into a sheet;
- and
- biaxially orienting the extruded sheet at a temperature in the range of about 5.degree. C. to about 20.degree. C. above the sheet glass transition temperature of the polyamide and at a draw ratio of at least about 1.5 in each direction.
Dependencies are inferred from the claim text.