Fourier transform infrared (FT-IR) analysis was used to investigate the conformation and the effects on crystals in syndiotactic polystyrene (sPS) subjected to different solvent and/or thermal treatments. It was found that the original helical conformation in sPS cast from a solution of 1,1,2-tetrachloroethane could transform to an all-trans planar conformation as the sPS was heated to temperatures above 200°C. The spectra of sPS showed that the helical conformation chain varied with different casting solvents and the band positions and relative intensities also differed slightly owing to different interactions between the solvent molecule and the σ-type sPS crystalline phase. The solution-casting temperature also had a significant effect on the crystal forms in sPS. Lower temperatures (casting below ∼ 100°C) produced helical crystals while the higher temperatures (casting above 120°C) yielded all-trans crystals. In addition, spectra evidence of different crystals (α- and βcrystals in all-trans conformation) in sPS are discussed and identified in this study.
- Solution cast
- Syndiotactic polystyrene (sPS)