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

Poly(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 CO 2 -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 CO 2 -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 CO 2 -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.