Personal care products, particularly hair care products, are made herein by mixing (A) a polymer having defined repeat units of a monomer (e.g. -olefin) maleic anhydride alkyl half-ester or full acid, maleamic acid and maleimide, which is derivatized with an amine, and (B) a compound or polymer having a carboxylic acid functionality. These products exhibit excellent high humidity curl retention properties, as well as an advantageous blend of toughness and cohesiveness, and a strong affinity to natural fibers, when applied to keratin-based fibers, e.g. hair, skin, or textiles, e.g. cotton, wool; and also they are water-soluble and water-resistant.