强疏水性PDMS/PVDF微孔膜的制备及其性能研究

Preparation and Structure of Superhydrophobic PDMS/PVDF Microporous Membranes

利用非溶剂相转化法(NIPS),通过在聚偏氟乙烯(PVDF)铸膜液中加入聚二甲基硅氧烷(PDMS),制备了PDMS/PVDF共混疏水微孔膜,并研究了凝胶浴组成(水/乙醇)对铸膜液凝胶动力学、膜形貌、疏水性及力学性能的影响。结果表明,随着凝胶浴中乙醇百分含量由零增加至100%时,PDMS/PVDF共混膜的断面上指状孔基本消失,海绵状孔结构贯穿断面;当凝胶浴中乙醇含量为100%时,PD)MS与PVDF发生分相;膜表面疏水性能增加,水接触角达到139.68°;弹性模量、拉伸强度、断裂伸长率分别由(48.06±4.20)、(2.82±0.15)MPa、(92.90±2.53)%下降至(15.70±2.83)、(0.72±0.13)MPa、(15.47±1.63)%。

Superhydrophobic PDMS/PVDF microporous membrane was prepared by solution casting and phase inversion. The influence of composition of coagulation bath on the precipitation rate of the casting solution, membrane morphology, pore structure, hydrophobicity, and mechanical properties were studied. It was found that as the ethanol content in coagulation bath increased from 0 to 100 wt%, the finger-like hole at cross-section of the membrane was gradually replaced by a sponge-like structure. When ethanol was used as the coagulation bath, phase separation occurred between PDMS and PVDF, the hydrophobicity increased and the contact angle reached 139.68°. Young＇ modulus, tensile strength, and elongation at break decreased from （48. 06 ± 4. 20）, （2. 82 ± 0. 15） MPa, and （92. 90±2.53）% to （15. 70±2. 83）, （0. 72±0. 13） MPa, and （15.47±1.63）%, respectively.