Melt Blending Modification of Commercial Polystyrene with Its Half Critical Molecular Weight, High Ion Content Ionomer, Poly(styrene–<i>ran</i>–cinnamic Acid) Zn Salt, toward Heat Resistance Improvement
Zixin Yu,
Jie Wang,
Peihua Li,
Dachuan Ding,
Xuan Zheng,
Chuanqun Hu,
Zhinan Gao,
Tao Hu,
Xinghou Gong,
Chonggang Wu
Affiliations
Zixin Yu
Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-weight Materials and Processing, and School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China
Jie Wang
Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-weight Materials and Processing, and School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China
Peihua Li
Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-weight Materials and Processing, and School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China
Dachuan Ding
Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-weight Materials and Processing, and School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China
Xuan Zheng
Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-weight Materials and Processing, and School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China
Chuanqun Hu
Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-weight Materials and Processing, and School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China
Zhinan Gao
Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-weight Materials and Processing, and School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China
Tao Hu
Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-weight Materials and Processing, and School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China
Xinghou Gong
Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-weight Materials and Processing, and School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China
Chonggang Wu
Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-weight Materials and Processing, and School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China
A half-critical weight-average molecular weight ( M ¯ w ) (approximately 21,000 g mol−1), high-ion-content Zn-salt poly(styrene−ran−cinnamic-acid) (SCA−Zn) ionomer was successfully synthesized by styrene−cinnamic-acid (10.8 mol %) copolymerization followed by excess-ZnO melt neutralization. At 220 °C, the SCA−Zn’s viscosity was only approximately 1.5 magnitude orders higher than that of commercial polystyrene (PS) at 102 s−1, and the PS/SCA−Zn (5−40 wt %) melt blends showed apparently fine, two-phased morphologies with blurred interfaces, of which the 95/5 and 90/10 demonstrated Han plots suggesting their near miscibility. These indicate that any PS−(SCA−Zn) processability mismatch was minimized by the SCA−Zn’s half-critical M ¯ w despite its dense ionic cross-links. Meanwhile, the SCA−Zn’s Vicat softening temperature (VST) was maximized by its cross-linking toward 153.1 °C, from that (97.7 °C) of PS, based on its half-critical M ¯ w at which the ultimate glass-transition temperature was approximated. Below approximately 110 °C, the PS/SCA−Zn (0−20 wt %) were seemingly miscible when their VST increased linearly yet slightly with the SCA−Zn fraction due to the dissolution of the SCA−Zn’s cross-links. Nevertheless, the 60/40 blend’s VST significantly diverged positively from the linearity until 111.1 °C, revealing its phase-separated morphology that effectively enhanced the heat resistance by the highly cross-linked SCA−Zn. This work proposes a methodology of improving PS heat resistance by melt blending with its half-critical M ¯ w , high-ion-content ionomer.
