Copolymerized polyamide resin, method for producing same, resin composition, and molded article formed from the copolymerized polyamide resin or the resin composition

A copolyamide resin composition comprising 100 parts by weight of the copolyamide resin of claim 1, 0 to 30 parts by weight of talc, and 10 to 150 parts by weight of an inorganic filler.

A method of producing a copolyamide resin comprising i) a diamine component comprising two or more diamines, and ii) a dicarboxylic acid component,

• wherein the diamine component comprises 70 mol % or more of a xylylenediamine comprising 20 mol % or more of p-xylylenediamine, and the dicarboxylic acid component comprises 70 mol % or more of a straight-chain aliphatic dicarboxylic acid having 6 to 18 carbon atoms, and
• the method comprises subjecting the diamine component and the dicarboxylic acid component to a polycondensation reaction, in the absence of a solvent, in a batchwise reaction tank equipped with a partial condenser, and conducting the polycondensation reaction by adding the diamine component to the molten dicarboxylic acid component continuously or intermittently while maintaining an inner pressure of the reaction tank at 0.1 MPaG or more and a reaction system at a temperature which allows a whole reaction system to be kept in fluid state, and by heating a vapor phase in the reaction tank to a temperature equal to or higher than a melting point of a nylon salt comprising the diamine component and the dicarboxylic acid component before adding 80% of a total amount of the diamine component.