Polyamideimide and preparation method thereof

Abstract

The invention provides a polyamideimide preparation method. The method includes: adding aromatic diamine, maleimide carboxylic acid and organic alkaline catalysts into a non-proton nitrogen-containingpolar organic solvent, stirring, heating to perform reflux reaction, drying after reaction to obtain an amino acid powder monomer with an imide group; adding the amino acid powder monomer, a hypophosphite catalyst and deionized water into a high-pressure polymerization reactor to realize self-condensation polymerization, completing the reaction to obtain suspension of a polyamideimide prepolymer,drying, performing vacuum solid-phase viscosity increasing to obtain polyamideimide in different molecular weights. The method is simple in process route, effective in organic solvent recovery, low in cost, free of equivalence ratio control of monomers and the like and easy to industrialize. The invention further provides polyamideimide prepared according to the method. The polyamideimide has great forming processing characteristics and has advantages of high strength, high modulus, high heat resistance and the like.

Description

technical field [0001] The invention belongs to the field of polymer materials, in particular to a polyamide-imide and a preparation method thereof. Background technique [0002] Polyamide-imide (PAI for short) is a high-temperature resistant thermoplastic engineering plastic with excellent performance. Because the molecular main chain contains both heat-resistant imide groups and flexible amide groups, PAI products not only have the properties of polyimide, such as heat resistance, low creep, high strength, high modulus, and solvent resistance. At the same time, it has excellent mechanical properties and molding processing properties of polyamide. It can be processed by conventional injection molding, extrusion, molding and other processes. Therefore, it is widely used in aerospace, military equipment, chemical equipment, electronic equipment and other fields. development prospects. [0003] At present, the PAI used in molding materials usually adopts the acid chloride me...

AI Technical Summary

Problems solved by technology

The production of PAI by the acid chloride method has been industrialized and the technology is relatively mature, but there are the following problems: (1) The key raw material trimellitic anhydride acid chloride is expensive and has poor storage stability. Determined as a substance of very high concern; (2) the acid chloride route involves the pre-polymerization, powder formation, thermal imidization and other process steps of polyamic acid, the route is long, and the difficulty of product performance stability control increases; (3) the acid chloride method is The HCl gas released during the production process will pollute the environment, corrode equipment and increase production costs

This method first uses gum rosin as raw material to prepare maleopimaric acid chloride, and then prepares PAI by melt polymerization with 1,6-hexamethylenediamine; Higher, not conducive to the synthesis of high molecular weight PAI

The document One-pot synthesis of linear and branched poly(amideaspartimide)s with good solubility in organic solvents introduces a method for preparing PAI using 4,4'-diaminodiphenylmethane and 4-maleimidobenzoic acid as raw materials , the process of this method is simple, but the whole reaction process is carried out in an organic solvent, the solvent consumption is large and the solvent recovery is difficult, and the molecular weight and distribution of the product are not easy to adjust

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