Substantive UV-absorbing, water-soluble, cationic polymers containing cinnamidoalkylamines and benzamidoalkylainines, with `inverse temperature dependant solubility` are described in the present invention. They are water-soluble at ambient conditions and yet they are water-resistant at the temperature of human body as well as in the presence of electrolytes. These properties make these macromolecules useful for personal care as well as fabric care products.The present invention also describes the hair, skin and fabric care compositions containing the said polymers of Formula I wherein, ArCO is an UV-absorbing moiety of an organic sunscreen acid or mixtures of organic sunscreen acids selected from p-methoxy cinnamic acid and p-dimethyl amino benzoic acid; R.sub.2 and R.sub.3 are selected from hydrogen, alkyl and cycloalkyl group containing from 1 to 6 carbon atoms; m is an integer from 5 to 9 and n is an integer between 1 to 5 and m+n=10 ##STR00001##