Solid phase-polymerized polyamide polymer
AssigneeMitsubishi Gas Chemical Company, Inc.
InventorKazumi Tanaka
Life of this patent
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Abstract
A solid phase-polymerized polyamide produced by solid phase polymerization of a melt-polymerized polyamide which has a specific relative viscosity and end group balance and is obtained by polycondensing a diamine component mainly comprising m-xylylenediamine with a dicarboxylic acid component mainly comprising adipic acid in molten state. The solid phase-polymerized polyamide is a medium to high viscosity polymer having a specific relationship between the relative viscosity and the number average molecular weight. With such particular properties, the solid phase-polymerized polyamide contains gels and fish eyes in extremely small amounts, and is suitable as a material particularly for producing bottle, sheet, film and fiber.
Claims18
A solid phase-polymerized polyamide which is produced by solid phase polymerization of a melt-polymerized polyamide obtained by polycondensing in molten state a diamine component containing not less than 80 mol % of m-xylylenediamine with a dicarboxylic acid component containing not less than 80 mol % of adipic acid, said melt-polymerized polyamide satisfying the following formulae (A) and (B):
- 1.83≦a≦2.28 (A)
- 8 μeq/g≦b≦82 μeq/g (B)
- wherein “a” is a relative viscosity measured at 25° C. on a solution of 1 g of said melt-polymerized polyamide in 100 cc of 96% sulfuric acid and “b” is [COOH]−[NH2] wherein [COOH] is a concentration (μeq/g) of end carboxyl groups and [NH2] is a concentration (μeq/g) of end amino groups;
- and said solid phase-polymerized polyamide satisfying the following formulae (C) and (D):
- 16500≦16200×d−c≦20000 (C)
- 2.30≦d≦4.20 (D)
- wherein “d” is a relative viscosity measured at 25° C. on a solution of 1 g of said solid phase-polymerized polyamide in 100 cc of 96% sulfuric acid and “c” is a number average molecular weight calculated from 2×106/([COOH]+[NH2]).
A solid phase-polymerized polyamide satisfying the following formulae (C) and (D):
- 16500≦16200×d−c≦20000 (C)
- 2.30≦d≦4.20 (D)
- wherein “d” is a relative viscosity measured at 25° C. on a solution of 1 g of said solid phase-polymerized polyamide in 100 cc of 96% sulfuric acid and “c” is a number average molecular weight calculated from 2×106/([COOH]+[NH2]), said solid phase-polymerized polyamide being produced by a process comprising the following sequential steps of:
- (1) polycondensing in molten state a diamine component containing not less than 80 mol % of m-xylylene diamine with a dicarboxylic acid component containing not less than 80 mol % of adipic acid, thereby obtaining a melt-polymerized polyamide having a crystallinity of not more than 13% and satisfying the following formulae (A) and (B):
- 1.83≦a≦2.28 (A)
- 8 μeq/g≦b≦82 μeq/g (B)
- wherein “a” is a relative viscosity measured at 25° C. on a solution of 1 g of said melt-polymerized polyamide in 100 cc of 96% sulfuric acid and “b” is [COOH]−[NH2] wherein [COOH] is a concentration (μeq/g) of end carboxyl groups and [NH2] is a concentration (μeq/g) of end amino groups;
- (2) charging said melt-polymerized polyamide into a batchwise heating apparatus and controlling a total water content in said batchwise heating apparatus to not less than 0.2% by weight based on the charged weight of said melt-polymerized polyamide;
- (3) heating said melt-polymerized polyamide to 60 to 160° C. in an atmosphere having an oxygen concentration of not more than 5% by volume without removing water from said batchwise heating apparatus while controlling a maximum temperature of a heat-transfer surface of said batchwise heating apparatus within 120 to 230° C., thereby promoting crystallization of said melt-polymerized polyamide;
- and
- (4) reducing an inner pressure of said batchwise heating apparatus to not more than 66500 Pa when a crystallinity of said melt-polymerized polyamide reaches at least 15%, and then heating further said melt-polymerized polyamide at a temperature at least 15° C. lower than the melting point thereof.
Dependencies are inferred from the claim text.