Abstract: The present disclosure discloses a semi-aromatic polyamide and a preparation method therefor. The semi-aromatic polyamide is obtained by polymerization reaction using a diamine, a dibasic acid and a monoacid as main raw materials while adding a special end-capping agent. The semi-aromatic polyamide prepared according to the present disclosure has good thermal stability, a yellowness index of less than 20, a glass transition temperature of 90° C. or above, and a melting point of 300° C. or above, and can be applied to spare parts for fuel pipelines in automobiles, and electronic and electrical industries such as LED panels.

Abstract: The present disclosure provides a production method of a semi-aromatic polyamide, and a semi-aromatic polyamide. Said production method of a semi-aromatic polyamide includes: step 1 of subjecting an initial charge of a diamine and a binary acid in an amine/acid molar ratio of less than 1.0 to form a slurry together with water and a catalyst, and subjecting the slurry to heating and dissolution to form a saline solution; step 2 of dehydrating said saline solution after detecting the composition thereof, detecting the content of diamine in a steam condensate from a dehydration unit, adjusting the amine/acid molar ratio to be larger than 1.0 by a molten diamine and a monoacid as a molecular weight regulator, and performing pre-polymerization; and step 3 of subjecting a pre-polymerization solution to post-polycondensation after vacuum flashing. The semi-aromatic polyamide of the present disclosure has a low gel content, excellent performance and extensive scope of application.

Abstract: The present disclosure provides a production method of a semi-aromatic polyamide, and a semi-aromatic polyamide. Said production method of a semi-aromatic polyamide includes: step 1 of subjecting an initial charge of a diamine and a binary acid in an amine/acid molar ratio of less than 1.0 to form a slurry together with water and a catalyst, and subjecting the slurry to heating and dissolution to form a saline solution; step 2 of dehydrating said saline solution after detecting the composition thereof, detecting the content of diamine in a steam condensate from a dehydration unit, adjusting the amine/acid molar ratio to be larger than 1.0 by a molten diamine and a monoacid as a molecular weight regulator, and performing pre-polymerization; and step 3 of subjecting a pre-polymerization solution to post-polycondensation after vacuum flashing. The semi-aromatic polyamide of the present disclosure has a low gel content, excellent performance and extensive scope of application.