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Controlled/living polymerization (CLRP) techniques have recently been developed that offer unprecedented opportunities for synthesis of materials with precisely tailored nano‐ and micro‐scale features. This account focuses on significant developments in the field of stimuli‐responsive block copolymers with immediate and future utility in advanced formulation and surface science. Specifically, stable free radial polymerization (SFRP), atom transfer polymerization (ATRP), and reversible addition fragmentation chain transfer (RAFT) polymerization techniques for preparation of responsive micelles and vesicles, stabilized nanoparticles, thin films, polymer brushes, and other ordered structures are described. Conformational changes in response to external stimuli are manifested in changes in physiochemical properties including surface wetting, adsorption, adhesion, lubricity, and permeability.*Paper number 120 in a series entitled Water Soluble Polymers. [ABSTRACT FROM AUTHOR]

Narrowly dispersed, temperature-responsive BAB block copolymers capable of forming physical gels under physiological conditions were synthesized via aqueous reversible addition fragmentation chain transfer (RAFT) polymerization. The use of a difunctional trithiocarbonate facilitates the two-step synthesis of BAB copolymers with symmetrical outer blocks. The outer B blocks of the triblock copolymers consist of poly(N-isopropylacrylamide) (PNIPAM) and the inner A block consists of poly(N,N-dimethylacrylamide). The copolymers form reversible physical gels above the phase transition temperature of PNIPAM at concentrations as low as 7.5 wt % copolymer. Mechanical properties similar to collagen, a naturally occurring polypeptide used as a three-dimensional in vitro cell growth scaffold, have been achieved. Herein, we report the mechanical properties of the gels as a function of solvent, polymer concentration, and inner block length. Structural information about the gels was obtained through pulsed field gradient NMR experiments and confocal microscopy.