Sokolov Stepan, Balynin Alexey, Bakhtin Danila, Borisov Ilya
A.V. Topchiev Institute of Petrochemical Synthesis RAS, Russian Academy of Sciences, 117912 Moscow, Russia.
Materials (Basel). 2021 Sep 6;14(17):5093. doi: 10.3390/ma14175093.
The influence of casting centrifugation process parameters, such as a rotation speed (ω), the amount of the film-forming solution (V), and its concentration (C) on transport properties of composite membranes were investigated. A number of composite membranes based on poly (1-trimethylsilylpropyne) (PTMSP) and micro- (MFFK-1) and ultrafiltration (UFFK) membranes were obtained using the spin-coating method. For the first time, an unexpected dependence of permeance and ideal selectivity on rotation speed had been discovered: the thickness of the selective layer decreases from 3.0 to 1.0 μm for MFFK-1 and from 1.7 to 1.1 μm for UFFK with an increase of spin coater rotation speed from 500 to 3000 rpm. However, the gas permeance of composite membranes in the range of 500-2000 rpm was reduced due to an increase of a penetration depth of PTMSP into a support layer porous structure (estimated by the EDX method). The permeance of the PTMSP/UFFK membranes was higher than PTMSP/MFFK-1 membranes due to a thinner selective layer and a lower penetration depth of polymer solution into the pores of the support. The highest CO/N selectivity values were achieved as 5.65 ± 0.9 at CO permeance 5600 ± 1000 GPU for PTMSP/UFFK membranes (C = 0.35%, V = 1 mL, ω = 1000 rpm), and 6.1 ± 0.5 at CO permeance 4090 ± 500 GPU for PTMSP/MFFK-1 membranes (C = 0.35%, V = 1 mL, ω = 2000 rpm).
研究了离心铸造工艺参数，如转速（ω）、成膜溶液量（V）及其浓度（C）对复合膜传输性能的影响。采用旋涂法制备了一系列基于聚（1-三甲基硅基丙炔）（PTMSP）以及微滤（MFFK-1）和超滤（UFFK）膜的复合膜。首次发现渗透率和理想选择性对转速存在意外的依赖性：随着旋涂机转速从500 rpm增加到3000 rpm，MFFK-1的选择性层厚度从3.0μm减小到1.0μm，UFFK的选择性层厚度从1.7μm减小到1.1μm。然而，由于PTMSP渗透到支撑层多孔结构中的深度增加（通过能量散射X射线谱（EDX）方法估算），复合膜在500 - 2000 rpm范围内的气体渗透率降低。由于选择性层较薄且聚合物溶液渗透到支撑体孔中的深度较低，PTMSP/UFFK膜的渗透率高于PTMSP/MFFK-1膜。对于PTMSP/UFFK膜（C = 0.35%，V = 1 mL，ω = 1000 rpm），在CO渗透率为5600 ± 1000 GPU时，最高CO/N选择性值达到5.65 ± 0.9；对于PTMSP/MFFK-1膜（C = 0.35%，V = 1 mL，ω = 2000 rpm），在CO渗透率为4090 ± 500 GPU时，最高CO/N选择性值为6.1 ± 0.5。
