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An abrupt phase change is the secret behind a new concept for designing polymeric materials whose stickiness and wettability can be turned on and off by a small change in temperature suggest that such materials could be used in nonsoiling grips for tennis rackets or golf clubs. At room temperature, the grip would not be sticky and so would not pick up dirt, but during use, the warmth of a player's hand would make the handle tacky, improving grip. Other potential uses include industrial coatings and cosmetics. The liquid-crystalline polymer is produced through radical copolymerization in butyl acetate of an acrylate monomer bearing a long fluorinated alkyl side chain (C8F17) and a methacrylate monomer bearing a long alkyl chain (C17H35). The polymer undergoes a reversible phase transition from a nonsticky, highly organized state to a tacky, disorganized state--much like a plate of branched spaghetti--at about 35 C. Temperature dependence can be changed by tinkering with the relative proportion of alkyl monomers and the length of the polymer's side chains
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