POLYMER GELATOR

摘要

The present invention relates to a polymer gelator which exhibits controllable liquid to gel phase transition behaviour. The polymer may be of formula A-B-L-B-A where A represents a polymer unit which, when polymer (I) is provided in an aqueous medium, exhibits an increase in hydrophobicity upon changing the temperature or pH of said aqueous medium from a first temperature or pH value to a second temperature or pH value. B represents a polymer unit which is more hydrophilic than polymer unit A when said aqueous medium is at said second temperature or pH value. L represents a linking group which is cleavable by hydrolysis, oxidation or reduction. The polymer may be a temperature dependent polymer gelator comprising polymers units C, D and E wherein polymer unit C is poly (2-hydroxypropyl methacrylate) and D is a polymer unit which, when said polymer gelator is provided in an aqueous medium, is more hydrophilic than polymer unit C. Each polymer may be provided in a polymer mixture in combination with a thermo-responsive diblock copolymer incorporating poly (2-hydroxypropyl methacrylate).