PURPOSE: To facilitate the production of the subject copolymer from an easily available copolymer consisting of structural ethylene units and structural carboxylic acid units by reacting the copolymer with a diamine and treating the resulting copolymer with a quaternizing agent.
CONSTITUTION: A copolymer consisting of 97.9-59mol% structural ethylene units represented by formula I and 2.1 to 41mol% structural carboxylic acid units represented by formula II is reacted with a diamine represented by formula III in an amount of 0.25-0.97mol per mol of the carboxyl groups of the copolymer. The resulting copolymer is reacted with a quaternizing agent represented by formula IV to effect quaterinizing and esterification, the amount of the compound (IV) being 0.3-0.96mol per mol of the sum of the tertiary amino groups introduced and the carboxyl groups remaining unreacted. The objective copolymer thus obtained contains the units (I) as the main component and further contains ester units represented by formula V, the units (II), and amide units represented by formula VI, and which has a weight- average mol.wt. of 1,000-50,000. In the formulae, R is H or CH3; R2 is a 2-8C alkylene; R3 and R4 each is a 1-4C alkyl; R5 is a 1-18C alkyl or an alkyl substituted with a 6-8C aryl; and X is a halogen, CH3OSO3, or C2H5OSO3.
NAKAYAMA YUTAKA
HOTTA HIROSHI