Novel hydrophobic polyvinyl alcohol–formaldehyde foams for organic solvents absorption and effective separation

Abstract

A novel macroporous and hydrophobic polyvinyl alcohol–formaldehyde foam (PVF-GA-H) with open-cell structure and good mechanical property was successfully prepared by the two-step substitution of the hydroxyl groups in polyvinyl alcohol–formaldehyde with glutaraldehyde and stearoyl chloride at ambient temperature. The as-prepared PVF-GA-H possessed fast absorption kinetics in a few seconds to organic solvents and can absorb organic solvents up to 89.3 g g⁻¹ even in the presence of water. These hydrophobic foams also exhibited highly effective reusability and recovery of organic solvents through a simple absorption–squeezing cycle. Meanwhile, the separation experiment confirmed that the PVF-GA-H foams can absorb and separate organic solvents from a water–organic solvent mixture. Therefore, this kind of foam is a highly suitable candidate for organic chemical pollution and industry leakage.