Al(OH)3胶体对PTFE微孔膜表面改性的影响

Surface Modification of PTFE Micro-porous Membrane by Al(OH)3 Gel

摘要:

通过AlCl3水解获得的Al(OH)3胶体，利用Al(OH)3胶体对聚四氟乙烯(PTFE)微孔膜进行亲水改性。探讨了吸附剂用量、氨水用量、浸渍温度、浸渍时间和分散剂聚合度对PTFE微孔膜吸附量的影响，采用超声振荡处理来考察微孔膜吸附的稳定性，通过接触角、FTIR和SEM对PTFE微孔膜的亲水性、化学成分和显微结构进行分析。实验结果表明：浸渍温度20 ℃，浸渍时间20 h，吸附剂(AlCl3, 1 mol/L)用量45 mL，氨水用量(wt%=25%) 86 mL，分散剂(PEG，3 g)聚合度2000时，PTFE微孔膜的吸附量达到最大值211.53 mg/g；在温度20 ℃下，超声处理1 h后，吸附量趋于稳定，表明Al(OH)3胶体能够稳定地吸附在微孔膜上，PTFE微孔膜的接触角从137.42°下降到105.29°。

Abstract:

Chemical adsorption was used to improve the hydrophilic of PTFE micro-porous membrane in this paper. Al(OH)3 gel was produced by AlCl3 solution to improve the surface properties of PTFE micro-porous membrane. The effects of impregnation temperature, impregnation time, amount of adsorbent, amount of NH3?nH2O and polymerization degree of dispersing agents on the adsorption of PTFE micro-porous membrane were investigated. Ultrasonic oscillation was used to measure the stability of PTFE adsorption. The properties of modified membrane were investigated by means of contact angel, FTIR and SEM. The results showed that the adsorptive value of PTFE micro-porous membrane achieved a maximum (211.53 mg/g) when impregnation temperature and time was 20 ℃ and 20 h respectively, AlCl3(1 mol/L) solution was 45 ml and NH3?nH2O(wt%=25%) was 86 ml. The adsorption reached equilibrium after the ultrasonic oscillating was treated for 1 h at pH 7 and 20 ℃, and contact angel of PTFE membrane decreased from 137.42° to 105.29.