Aggregation and precipitation phenomena in N-phenyl poly(iminomethylene)($\Phi$PIM)

Jiun Tang Huang, University of Rhode Island


N-Phenyl poly(iminomethylene), derived from the phenyl isocyanide monomer, has been discovered to be an appropriate model for some biologic systems because it has a helical structure like a living biopolymer. Since the first systematic study of isocyanide polymerization in the 1960s, many chemical reactivities and physical properties of isocyanide polymers have been explained using the assumption that the molecular structure of the polymer has a helical, rigid rod like configuration. The rigid rod like structure seemed to be reinforced when more bulky substituents were on the polymer side chain. As this helical configuration was usually studied when steric hindrance was prevalent in the bulky substituent on the nitrogen atom of the polymer, it has not been clear if less steric hindrance associated with this substituent would still maintain a helical, rigid rod conformation for the polymer. Based on $\sp{13}$C NMR and photon correlation spectral data other workers concluded that the stereoregular 4/1 helical rigid rod structure was an over simplification for their model of sterically unhindered polymers. In this dissertation we use a planar substituent on nitrogen, a phenyl ring, which provides little steric hindrance so studies can examine if the helical, rigid rod like configuration is a viable concept for this polymer. Using several instrumental techniques we conclude that while a helical, rod-like configuration is produced initially upon preparation of the polymer, subsequent dissolution of the polymer in solution disrupts the rod-like order leading to a random coil polymer which is susceptible to aggregation and precipitation. ^

Subject Area

Chemistry, Polymer

Recommended Citation

Jiun Tang Huang, "Aggregation and precipitation phenomena in N-phenyl poly(iminomethylene)($\Phi$PIM)" (1996). Dissertations and Master's Theses (Campus Access). Paper AAI9707385.