AbstractShapememory polymers (SMPs) are selfadjusting, smart materials in which shape changes can be accurately controlled at specific, tailored temperatures. In this study, the glass transition temperature (Tg) is adjusted between 28 and 55C through synthesis of copolymers of methyl acrylate (MA), methyl methacrylate (MMA), and isobornyl acrylate (IBoA). Acrylate compositions with both crosslinker densities and photoinitiator concentrations optimized at fractions of a mole percent demonstrate fully recoverable strains at 807% for a Tg of 28C, at 663% for a Tg of 37C, and at 553% for a Tg of 55C. A new compound, 4,4di(acryloyloxy)benzil (referred to hereafter as Xini) in which both polymerizable and initiating functionalities are incorporated in the same molecule, was synthesized and polymerized into acrylate shapememory polymers, which were thermomechanically characterized yielding fully recoverable strains above 500%. The materials synthesized in this work were compared to an industry standard thermoplastic SMP, Mitsubishi's MM5510, which showed failure strains of similar magnitude, but without full shape recovery: residual strain after a single shapememory cycle caused largescale disfiguration. The materials in this study are intended to enable future applications where both recoverable highstrain capacity and the ability to accurately and independently position Tg are required.
