Nonsolvent induced phase separation preparation of poly(vinylidene fluoride-co-chlorotrifluoroethylene) membranes with tailored morphology, piezoelectric phase content and mechanical properties

作者：Cardoso V F^*; Botelho G; Lanceros Mendez S

来源：Materials and Design, 2015, 88: 390-397.

DOI：10.1016/j.matdes.2015.09.018

• Poly(vinylidene fluoride-chlorotrifluoroethylene) - P(VDF-CITE)
• Nonsolvent induced phase separation - NIPS
• Tailored microstructure
• Crystalline phases
• Mechanical properties

Poly(vinylidene fluoride-co-chlorotrifluoroethylene) - P(VDF-CTFE) membranes are increasingly interesting for a wide range of applications, including battery separators, filtration membranes and biomedical applications. This work reports on the morphology, hydrophobicity, thermal and mechanical properties variation of P(VDF-CTFE) membranes processed by nonsolvent induced phase separation (NIPS) technique as a function of the main processing parameters. All membranes show a porous structure composed of large spherulites, (interconnected) micropores and/or microvoids depending on the processing conditions used that in turn affect their hydrophobicity and mechanical properties. The degree of crystallinity of the membranes remains approximately constant with a value of about 15%, except for the membranes immediately immersed in ethanol, which is of about 23%. In turn, the crystalline phases present in the copolymer is mainly affected by the temperature and nonsolvent characteristics of the coagulation bath, the beta-phase content ranging from 33 to 100%, depending on those processing parameters. It was show that the temperature of water-based coagulation bath plays an important role in order to produce structurally uniform and homogeneous porous membranes, which is particularly important from the point of view of technological applications.

• 出版日期2015-12-25