An
acrylamide derivative of the following general formula (I) is used to prepare a
polymer or
copolymer:wherein R1 represents a
hydrogen atom, a straight-chain or branched
alkyl group containing 1 to 4 carbon atoms or a C3-6 cycloalkyl group, R2 and R3 each independently represent an alkylene group containing 1 to 6 carbon atoms or R2 and R3 may be combined to form a ring, X represents a
hydrogen atom, an amino group, a hydroxyl group, a
halogen atom, a carboxyl group or a -COOR4 group wherein R4 represents a C1-6 straight-chain or branched
alkyl, C3-6 cycloalkyl, phenyl, substituted phenyl, benzyl or substituted
benzyl group, and Y represents an amino group, a
halogen atom, a carboxyl group or a -COOR4 group wherein R4 represents a C1-6 straight-chain or branched
alkyl, C3-6 cycloalkyl, phenyl, substituted phenyl, benzyl or substituted
benzyl group. The thus obtained
polymer or
copolymer is a
polymer or hydrogel incorporating many functional groups while maintaining the sensitive
temperature response.