hydroxamic acid polymers which are comprised of hydroxamic groups and carboxylic acid groups wherein the carboxylic acid groups constitute less than about 3 % of the functional groups . the polymers hereof are also especially useful in biomedical applications because , for example , the low concentration of carboxylic acid groups decreases the incidence of bioincompatibility . additionally , the polymers exhibit anticoagulant activity , urease inhibition activity , metal chelating activity and ion exchange activity .