溶剂改性聚酰胺膜的研究

SOLVENT MODIFICATION OF POLYAMIDE MEMBRANE

实验选用聚酰胺(PA)的良溶剂醋酸作为PA膜的改性剂。改性膜对不同醇的溶胀率是随着醇中碳原子数的增加而增加。溶剂改性条件(改性时间、改性剂浓度)对改性膜的吸着性能有明显影响。随着改性时间的延长,改性膜对水的溶胀率都呈下降趋势,而对异丙醇(IPA)的溶胀率基本上是先增大后减小。随着改性剂浓度的增大,改性膜对水和IPA的溶胀率都是先上升后下降,而且当醋酸浓度为6%～8%时,都达到最大值。红外光谱分析表明,醋酸改性对PA的化学结构并没有产生影响,吸着性能的变化主要来自于改性过程PA膜物理结构的变化。

Better solvent acetic acid for polyamide (PA) was selected as the modifying agent in this study. As the number of carbon atom of the alcohols increased, the swelling rate (S) of the modified membrane in different alcohols also increased. The effect of the modifying conditions (such as concentration of the modifying agent, processing time of membrane in modifying agent) on the sorption of modified membrane was marked. As the modification time was prolonged, SIPA increased firstly and then decreased, while SW decreased. As the concentration of the modifying agent increased, SW and SIPA all increased firstly and then decreased. Furthermore, both SW and SIPA reached maximum when the concentration of acetic acid was 6%～8%. Infrared spectroscopy analysis indicated that the modification didn't affect the chemical structure of PA. The different sorption of modified membrane was due to the change of the physical structure of PA membrane in modification course.