Surface Modification of Hypercrosslinked Vinylbenzyl Chloride PolyHIPEs by Grafting via RAFT

• Published in: Macromolecular chemistry and physics 2021-02, Vol.222 (3), p.n/a
• Main Authors: Koler, Amadeja, Krajnc, Peter
• Format: Article
• Language: English
• Subjects: Chain transfer; Chlorides; Divinylbenzene; Emulsion polymerization; Friedel-Crafts reaction; Grafting; hypercrosslinking; polyHIPE; polyvinylbenzyl chloride; porous polymers; RAFT; Reagents; tris(2‐aminoethyl) amine
• ISSN: 1022-1352; 1521-3935
• DOI: 10.1002/macp.202000381

Grafting of glycidyl methacrylate from the surface of macroporous poly(4‐vinylbenzyl chloride‐co‐divinylbenzene) polyHIPEs (poly high internal phase emulsions) prepared by the polymerization of the continuous phase of high internal phase emulsions is performed. PolyHIPEs are hypercrosslinked using Friedel–Crafts reaction thus increasing specific surface area, and further functionalized with tris(2‐aminoethyl) amine. To the free amino groups reversible addition–fragmentation chain transfer (RAFT) agent 4‐cyano‐4‐[(dodecylsulfanylthiocarbonyl) sulfanyl] pentanoic acid is immobilized and grafting is performed utilizing glycidyl methacrylate. Poly(glycidyl methacrylate) chains of ≈100 units in length are grafted onto the surface of the polyHIPEs. In comparison, non‐hypercrosslinked monoliths allow for substantially lower degree of immobilization of RAFT agent suggesting decreased accessibility of active sites on the polymer surface. Cellular porous poly(4‐vinylbenzyl chloride) is prepared from high internal phase emulsions and hypercrosslinked. Tris(2‐aminoethyl) amine is immobilized to chloromethyl groups and reversible addition–fragmentation chain transfer agent to free amino groups followed by grafting of glycidyl methacrylate. Short length grafts of poly(glycidyl methacrylate) are created on the surface of porous polymer with bimodal pore size distribution and high surface area.