Preparation Of Acrylamide-based Polyhipes By Templating High Internal Phase Co₂-in-water Emulsions And Their Applications

In view of the rare types of surfactant and the high CO2 pressure in the formation of green CO2-in-water(C/W)emulsions as well as the flat research of preparing polymer porous materials by templating C/W emulsions,the new type of efficient poly(vinyl acetate-alt-dibutyl maleate)-block-poly(ethylene glycol)(PVDBM-b-PEG45)hydrocarbon copolymers were synthesized and used as surfactants to form high internal phase(80%)C/W emulsions that remained stable longer than 24 hours under mild conditions(25?,8 MPa).Then,highly interconnected porous polyacrylamide(PAM)monoliths were prepared based on the stable C/W emulsions by thermal-initiation polymerization.The opening rate was as high as 93.83%,and the density was as low as 0.047 g/cm3.The effects of the surfactant concentration and the length of the CO2-philic tails of the surfactants on the porous structures and compressive strength of PAM materials were investigated.It was found that the PAM material with the smallest average pore diameter(11.12 ± 0.62 ?m)and the higher compressive modulus(22.65±0.10 MPa)could be obtained by using the short CO2-philic chains of the PVDBM3-b-PEG45 surfactant at the concentration of 1.0 wt%.Moreover,with the addition of N-hydroxymethyl acrylamide(HMAM)comonomers,the compressive modulus of the obtained poly(acrylamide-N-hydroxymethyl acrylamide)[P(AM-co-HMAM)]material could be increased by three times without changing the pore structure of the material.Both PAM and P(AM-co-HMAM)materials were employed as scaffolds to guide the growth and proliferation of H9c2 cardiac muscle cell and MRC-5 human embryonic lung fibroblast cell.Fluorescence imaging showed that all of these materials have good biocompatibility,and a smaller average pore diameter and a narrower pore-size distribution were more beneficial to the growth and proliferation of H9c2 cell on the surface of materials.