Temperature and pH sensitive polymers in water ‐ from solution to thin films

A series of temperature and pH sensitive polymers which contain both temperature and pH sensitive components were synthesised by copolymerization of N-isopropylacrylamide (NIP AAm) and acrylamide derivatives containing a spacer and a sensitive headgroup. The cloud point and heat of transition (ΔH PT ) of aqueous solutions of polymers with various compositions were measured by means of DSC. The observed cloud points and ΔH PT values strongly depend on the polymer composition and the pH value. The irradiation of dimethylmaleinimide groups (DMIAAm) bearing copolymers with UV light resulted in crosslinking of the polymers. The prepared thin layers showed fast temperature dependent swelling with transition temperatures similar to the uncrosslinked polymers.

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