Semi-aromatic polyamide and preparation method thereof

Abstract

The invention discloses a semi-aromatic polyamide and a preparation method thereof. The method of the invention uses the aromatic dicarboxylic acid and aliphatic diamine containing 4 to 14 carbon atoms as the raw materials in order to prepare the semi-aromatic polyamide and acquire a new structure of the semi-aromatic polyamide. The semi-aromatic polyamide is prepared by combining high purity semi-aromatic polyamide salt so the polyamine loss is avoided and the mole ratio of the dicarboxylic acid and the diamine can be accurately controlled so as to acquire the high viscosity semi-aromatic polyamide. The monomer is purified in the salifying process, so the melting point, the crystallinity and the mechanical property of the semi-aromatic polyamide are promoted. The pre-polymerized material which has a viscosity eta ranged from 0.06 to 0.3 dl / g tested in 96% sulfuric acid at 25 DEG C by performing the pre-polymerization reaction is acquired. After the tackifying reaction is performed, the viscosity eta of the semi-aromatic aromatic polyamide is ranged from 0.8 to 2.5 dl / g, the melting point of the semi-aromatic aromatic polyamide is ranged from 270 to 330 DEG C, the content of the end carboxyl is ranged from 15 to 80 mol / t and the content of the end amino is ranged from 15 to 80 mol / t.

Description

technical field [0001] The invention relates to the preparation technology of semi-aromatic polyamide. Background technique [0002] Aliphatic polyamides, such as PA6 and PA66, have excellent mechanical strength, heat resistance, chemical resistance, wear resistance and self-lubricating properties, and low coefficient of friction. Their applications include electronic appliances, automotive parts, furniture , building materials and fibers, has become one of the most important engineering plastics. [0003] Semi-aromatic polyamide is a polyamide resin prepared by polycondensation of diamines or dicarboxylic acids with aromatic rings and aliphatic dicarboxylic acids or diamines, and is one of the aromatic polyamides. Due to the introduction of aromatic rings into the main chain of polyamide molecules, the heat resistance and mechanical properties are improved, the water absorption rate is reduced, and it has a more suitable performance / price ratio. It is between general engin...

AI Technical Summary

Problems solved by technology

[0010] In the prior art, there is no report on the preparation of semi-aromatic polyamides from aromatic dicarboxylic acids and aliphatic polyamines containing 4 to 14 carbon atoms.