Abstract: The present application provides a high temperature resistant semi-aromatic polyamide resin and a preparation method thereof, a composition, and an article. Polymeric monomers of the polyamide resin include a diamine monomer and a diacid monomer, where the diamine monomer includes a diamine monomer A1 and a diamine monomer A2, and the diacid monomer includes a diacid monomer B1 and a diacid monomer B2. The carbon atom number CA1 of the diamine monomer A1 and the carbon atom number CA2 of the diamine monomer A2 satisfy that CA1?CA2?4, the diacid monomer B1 is selected from aromatic dicarboxylic acids with a carbon atom number of 7-12 and derivatives thereof, and the diacid monomer B2 is selected from aliphatic dicarboxylic acids with a carbon atom number of 4-18.

Abstract: The present disclosure provides a semi-aromatic copolyamide, its preparation method, compositions, and a molded product thereof. The semi-aromatic copolyamide is formed from raw materials including diacid monomers and diamine monomers. The diacid monomers include aromatic diacid or derivatives of the aromatic diacid and aliphatic diacid. The diamine monomers include decamethylene diamine and pentamethylene diamine. The molar ratio of the decamethylene diamine to the pentamethylene diamine is in a range of 1:1 to 30:1.

Abstract: The present invention provides a process for producing a high temperature resistant polyamide, the high temperature resistant polyamide and the use thereof. The process comprises: optionally concentrating a polyamide salt solution, and then conducting the following operations: heating and pressurizing to a pressure of P1, and maintaining the pressure, wherein the temperature of the system is T1 at the end of the pressure-maintenance; depressurizing to a pressure of P2, wherein the temperature of the system is T2 at the end of the depressurization; and evacuating, whereby a polyamide melt is obtained; wherein P1 is 0.8-4 MPa, T1 is 250-290° C., T1<T2 and (T2?T1)/(P1?P2)=5-75. The process for producing a high temperature resistant polyamide according to the present invention is simple to operate and reduces energy consumption.