A semiconducting pyrrole-styrene block copolymer film was electrochemically synthesized in nitromethane. The product polymer was confirmed to be a copolymer of pyrrole and styrene and not a composite or a blend of PPy and PSt through electrochemical, spectral, and dissolving experiments.

The partially disentangled poly(vinyl chloride) (PVC) samples were prepared by freezeextracting from dilute PVC/THF solutions. The conformation of these samples was investigated by infrared and Raman spectroscopy. The structural relaxation behaviors were studied by differential scanning calorimeter (DSC). The results showed that the PVC samples prepared from dilute solutions with concentrations lower than 0.25% were in the expanded state with fewer entanglements. The conformation and structural relaxation of PVC depended strongly on the entanglements in polymers, and the structural relaxation rate increased with decreasing chain entanglements, which is in good agreement with the modeling predictions.

Poly(vinyl chloride) (PVC) samples for the conformation and structural relaxation studies were prepared by freeze-extracting the solutions in various solvents and with varying concentrations. The partially disentangled PVC samples could be obtained by freeze-extracting very dilute PVC/tetrahydrofuran (THF) and PVC/dimethyl phthalate (DMP) solution (0.05 wt %), while the PVC sample remains in an entangled state after freeze-extracting the concentrated solutions in THF and in DMP. Surprisingly, the extent of interpenetration of PVC chain decreases, even in concentrated solution in dioctyl phthalate (DOP) (5 wt %), which is contrary to accepted theories. DSC and infrared spectroscopic studies showed that a higher ordered conformation could be achieved for the disentangled specimens recovered from concentrated solution in DOP than for the entangled samples prepared from THF and DMP. DSC heating curves showed strong and sharp endothermal peaks for the disentangled polymer after sub-Tg annealing. The structural relaxation behavior of the disentangled PVC freeze-extracted from DOP solutions is more predominant, which is in good agreement with the modeling predictions.

The laser-induced chemical reactions on the surface of a polymer film were investigated by surface-enhanced Raman scattering (SERS) using chemically deposited silver as the SERS activating layer on the surface of the film. The silver-catalyzed pyrolysis at the outermost surface of the polyacrylonitrile film under laser radiations with different wavelengths was investigated by this SERS technique. The extremely low carbonization temperature at room temperature under laser implies several responsible mechanisms.