abstract |
Ultraviolet light stabilizers are chemically bound to anhydride containing polymers or copolymers. The polymeric stabilizers are prepared by the reaction of primary amino or hydrazido-substituted UV absorbers with some or all of the anhydride groups of the polymer or copolymer to form pendant stabilizer substituted imide or amic acid groups. The polymer bound stabilizers are not lost from the polymer system by volatilization, migration, or extraction, even at high temperature. The polymer of this invention may be used as they are or as concentrates to stabilize other polymer systems. |