Preparation of acrylamide‐based poly‐HIPEs with enhanced mechanical strength using PVDBM‐b‐PEG‐emulsified CO2‐in‐water emulsions

Abstract

ABSTRACTPoly(vinyl acetate‐alt‐dibutyl maleate)‐block‐poly(ethylene glycol) (PVDBM‐b‐PEG) copolymers were synthesized via reversible addition–fragmentation chain transfer radical polymerization and used as emulsifiers to form stable CO2‐in‐water high internal phase emulsions (C/W HIPEs). Then, highly interconnected cellular polyacrylamide (PAM) and poly(acrylamide‐co‐N‐hydroxymethyl acrylamide) [P(AM‐co‐HMAM)] poly‐HIPEs with enhanced mechanical strength were prepared based on the stable C/W HIPEs. The porous structures of the PAM poly‐HIPEs, as well as morphology and compressive modulus, could be influenced by the surfactant concentration and the length of the CO2‐philic tails of the surfactants. PAM poly‐HIPEs with the smallest average pore diameter (11.12 ± 0.62 μm) and the highest compressive modulus (22.65 ± 0.10 MPa) could be obtained by using the short CO2‐philic chains of the PVDBM‐b‐PEG surfactant at a high concentration (1.0 wt %). Moreover, with the copolymerization of N‐hydroxymethyl acrylamide (HMAM) comonomers with acrylamide, the compressive modulus of the obtained P(AM‐co‐HMAM) poly‐HIPEs was three times higher than that of PAM poly‐HIPEs. Both PAM and P(AM‐co‐HMAM) poly‐HIPEs were employed as scaffolds to guide H9c2 cardiac muscle cellular growth. Fluorescence images showed that a smaller average pore size and a narrower pore‐size distribution were helpful for cell growth and proliferation on these materials. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46346.