Preparation of porous poly(4‐tert‐butylstyrene) based monoliths with high efficiency for oil‐water separation via high internal phase emulsion template

Abstract Developing low‐cost and highly efficient hydrophobic absorbents via simple and environmentally friendly method is demanded for oil‐water separation. This paper reports the preparation of hydrophobic absorbents of porous poly(4‐tert‐butylstyrene‐ co ‐divinylbenzene) (poly( t BS‐ co ‐DVB)) via high internal phase emulsion (HIPE) template method. The effects of crosslinking degree and internal phase volume fraction on the porous structure and adsorption performance of the absorbents are investigated. As the t BS/DVB molar ratio increases from 1:1 to 4:1, the adsorption performance of poly( t BS‐ co ‐DVB) toward hexane first increases to a maximum at a molar ratio of 3:1 and then decreases. As the internal phase volume fraction increases, the specific surface area (SSA) and porosity of the poly( t BS‐ co ‐DVB)s notably increase from 33.06 m 2 /g and 84.07% to 102.89 m 2 /g and 92.94%, respectively. When the internal phase fraction is 95 vol%, the obtained poly( t BS‐ co ‐DVB) foam with a water contact angle of 140° shows an absorbing capacity as high as 70.21 g/g for dichloromethane. After 10 consecutive adsorption‐desorption cycles, the adsorption performance of the poly( t BS‐ co ‐DVB) foam shows only a slight decrease, indicating an excellent recycling ability. The obtained poly( t BS‐ co ‐DVB) foams exhibit the advantages of facile preparation, high oil absorption capacity and satisfactory recoverability, which enable them potential as sustainable oil adsorbents.