Thermal response of poly(ethoxyethyl glycidyl ether) grafted on gold surfaces probed on the basis of temperature-dependent water wettability.

Two series of thiol-modified poly(ethoxyethyl glycidyl ether) with different chain-end groups and molecular weights (PT-PEEGE-SH and Bu-PEEGE-SH), which undergo lower critical solution temperature (LCST)-type phase separation in an aqueous milieu, are grafted onto gold substrates through Au-S bonding. The water wettability of the resultant polymer-tethered surface discontinuously varies with temperature, and this alteration of wettability is reversible according to the variation in temperature of the environment. For all the polymers examined, the transition temperature on surface, TC(surf), the temperature at which half the discontinuous change in surface wettability occurs, increases with the number-average molecular weight (M(n)).