Polyamide-imide

Polyamideimides, called in short form PAI are polymers which comprise both amide and imide groups.

Application

Polyamidoimides with aromatic units in the polymer chain by the pure polyimides the most thermally stable polymers based on carbon. In addition, a high chemical resistance and abrasion resistance is given. Polyamidoimides be as heat-resistant electrical insulation and foil coatings (English Overcoats ) of wire enamels and commonly used as a heat-resistant coating. The Continuous temperature is over 220 ° C.

Production

There is extensive patent literature on the manufacture, however, in most cases, heat-resistant polyamide-imides based on Trimellitsäurederivaten, preferably trimellitic acid anhydride (TMA) and described aromatic diamines and isocyanates.

There are two production routes. Trimellitic anhydride is dissolved in the solvents listed below, and with 4,4 '- diaminodiphenylmethane (MDA ) in the presence of dehydrating agents, or it is 4,4 '- methylene diisocyanate (MDI) is reacted, the isocyanate groups with elimination of carbon dioxide, the amide - form or imide group. Polyamideimide is usually as a solution in N-methylpyrrolidone ( NMP ), dimethylformamide (DMF) or dimethylacetamide (DMAc) put on the market. Well-known manufacturers are Solvay and BASF.