Polymers for High Strength, Nonlinear Optics, and Electrical Conductivity

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Two families of new polymers will be prepared: a) methylenealkoxy-substituted poly(isocyanates) and the unknown poly(isocyanic acid) and b) methylenealkoxy-substituted poly(carbodiimides) and the unknown poly(carbodiimide) ?poly)cyanamide) or poly (guanidine)! as well as copolymers within each family. Because of the highly polar repeat unit, these polymers are expected, upon polarizing in high electric fields, to produce ferroelectric solids akin to poly (vinylidene fluoride). Ferroelectric solidss have applications as peizoelectrics (e.g., transducers such as sensitive microphones) and nonlinear optics (mode converters, modulators, Y-branch interferometers, and directional couplers). Other salient features of this research are: 1.) Poly(isocyanic acid), due to its high degree of hydrogen bonding and the strength of the amide linkage, is expected to be superior to any known synthetic fiber in strength, strength on compression, toughness and oxidative stability. 2.) The substituted poly(carbodiimides) will be prepared in chiral form and depolymerized. Thus, a novel carbodiimide optical resolution procedure based on thermal depolymerization of a chiral poly(carbodiimide will be prepared. The chiral carbodiimide is a fundamentally new functional group. 3.) The parent, unsubstituted poly(carbodiimide), will become conjugated at intermediate protonation levels and will be converted to a highly conducting form upon further protonation via a new concept of protonative positive soliton generation.