In situ investigation of formation kinetics of microporous structure in PVDF thin films prepared via thermally‐induced phase separation (TIPS): Effects of film thickness and polymer concentration. Issue 7 (4th February 2021)

• Record Type: Journal Article
• Authors: Yang, Bin; Yu, Yang‐nan; Pan, Yang; Wang, Shu‐qing; Xu, Xiang; Wang, Ying‐ying; Qian, Jia‐sheng; Xia, Ru; Zhang, Peng; Shi, You; Tu, You‐lei
• Is Part Of: Nano select. Volume 2:Issue 7(2021)
• Page Start: 1403
• Page End: 1416
• Publication Date: 2021-02-04
• Subjects: diluent -- polyvinylidene fluoride (PVDF) -- temperature gradient fields -- thermally‐induced phase separation (TIPS); Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.5
• DOI: 10.1002/nano.202000304
• Languages: English
• ISSNs: 2688-4011

Abstract

Abstract: In this research, series of PVDF microporous films with various polymer concentrations and thickness were prepared through thermally‐induced phase separation in air condition with diphenyl carbonate as the diluent. Effects of polymer concentration and film thickness on the formation kinetics of microporous structure of PVDF thin films were in situ investigated via TII technique. The instantaneous heat conduction inside the films during film formation was also evaluated. Two types of parameter models were adopted in order to disclose the time and location dependence of TIPS film solidification kinetics, respectively. Hierarchical microstructures, crystallization behavior and thermal properties of the TIPS films were also characterized by SEM, DSC, and TGA, respectively. The current study could supply an insight into the fabrication of PVDF microporous films with target microstructure and desirable performance. Abstract : Formation of hierarchical microstructure in TIPS films is significantly affected by film thickness and polymer concentration. The cooling rate decreases with an increasing polymer concentration, leading to the formation of co‐continuous structure. With increasing polymer concentration, TIPS films tend to display smaller pores and lower porosity.