Plasma-Induced Graft Polymerization Inside Pores of Porous Substrates Assisted by an Infiltration Agent in Acidic Conditions

• Published in: Plasma processes and polymers 2014-04, Vol.11 (4), p.306-314
• Main Authors: Chi, Xueqin, Ohashi, Hidenori, Yamaguchi, Takeo
• Format: Article
• Language: English
• Subjects: acidic condition; graft copolymers; Grafting; Infiltration; Membranes; Monomers; plasma treatments; Polymerization; Porosity; Radicals
• ISSN: 1612-8850; 1612-8869
• DOI: 10.1002/ppap.201300109

Plasma‐induced graft polymerization (PIGP) is an efficient method for constructing functionalized pore‐filling type materials. This study imparts new information about the significance of substrate infiltration process and pH of the monomer solution that determines the degree of grafting via PIGP inside pores. Herein, we report that high‐density grafting of 2‐acrylamido‐2‐methylpropane sulfonic acid on porous polyethylene membrane can be achieved by incorporating an infiltration agent under acidic condition. In addition, this technique is unique in its initiation step: it proceeds even after most radicals has disappeared prior to polymerization at temperature ranging from 25 to 40 °C, which is much lower than conventionally used 80 °C. It offers a very facile PIGP method for thermally labile monomers. Plasma‐induced graft polymerization (PIGP) proceeds at temperatures as low as 25 °C, even when most radicals decay prior to polymerization. It has been found that solution infiltration and pH are essential for PIGP on a porous substrate. By adding an infiltration agent and applying a proper pH, pore‐filling type membrane can be made directly from sulfonic monomer.