Polyamide resin compsn. used in powder coating - contg. carboxyl- and amine-terminated components, which can be pulverised at ambient temp.

摘要

Polyamide resin compsn. suitable for powder coating, contains a polyamide (I) in which min. 70% of the end gps. are carboxylic acid gps. and another polyamide (II) in which min. 70% of the end gps. are amine gps. The compsn. pref. has a relative viscosity of 1.10-1.30 in 0.5% m-cresol soln. The total equiv. of carboxylic acid to amine gps. in (I) and (II) is 40:60 to 60:40. The powder is a prod. of solid phase polymerisation and pref. also contains a polymerisation catalyst. USE/ADVANTAGE - The powder gives a coating of sufficient thickness on the sides of the article to be coated. It is suitable for fluidised sintering and electrostatic coating and gives coatings with good friction, wear, strength and heat resistance. It can be produced by mixing (I) and (II) with low deg. of polymerisation (DP), pulverisation and solid phase polymerisation to the required powder, without the need to use liq. N2 for pulverisation.