Preparation of hypercrosslinked polymers with cashew nut shell liquid for removal of volatile organic compounds

Hypercrosslinked polymers (HCPs) have aroused considerable attention due to their high chemical stability and potential applications in adsorption. A series of HCPs were prepared via one-step solvent knitting method using the cashew nut shell liquid (CNSL) as bio-based building block. Characterization of the prepared samples was performed by N 2 adsorption, Fourier transform infrared, Raman spectra, solid-state 13 C NMR spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy, and transmission electron microscopy images. Depending on the N 2 adsorption, the as-prepared CNSL-HCP4 exhibits the highest specific surface area of 93 m 2 ·g −1 and displays a uniform pore-size distribution. TGA results show that the decomposition temperature of the polymers exceeds 350°C. More significantly, the dynamic adsorption of high concentration of volatile organic compounds (VOCs) was investigated with CNSL-HCP4 under dry and humid conditions. The results show that the maximum adsorption capacity of o -xylene under dry conditions is 217 mg·g −1 and its corresponding adsorption amount (208 mg·g −1 ) decreases slightly under 30% relative humidity condition, indicating that CNSL-HCP4 had a hydrophobic surface. A little decrease in adsorption capacity of o -xylene on CNSL-HCP4 after five recycles confirms the reusability of the CNSL-HCPs. Therefore, CNSL-HCP4 is considered to be a promising candidate for potential adsorbent in recycling the VOCs from the exhaust.