Biobased Microspheres Consisting of Poly(<i>trans</i>-anethole-<i>co</i>-maleic anhydride) Prepared by Precipitation Polymerization and Adsorption Performance

This paper reports the first biobased microspheres derived from phenylpropenic resources. To explore the potentials of biomass derived <i>trans</i>-anethole (ANE) and to develop new biobased polymeric materials, ANE was used for preparing an unprecedented kind of polymeric microspheres constructed by poly­(<i>trans</i>-ANE<i>-<i>co</i>-</i>maleic anhydride) [poly­(ANE<i>-<i>co</i>-</i>MAH)] through free radical precipitation polymerization in methyl ethyl ketone/<i>n-</i>heptane mixed solvent with 2,2′-azobis­(isobutyronitrile) as the initiator. Microspheres (about 1 μm in size) with spherical morphology and narrow size distribution were obtained under appropriate conditions. Following the same preparative strategy, cross-linked microspheres were further prepared with divinylbenzene as a cross-linking agent and then subjected to hydrolyzation of the surface anhydride groups into carboxyl groups, aiming at developing microsphere adsorbents. The hydrolyzed microspheres exhibited considerable adsorption ability toward trivalent chromic ion [Cr­(III)] and an organic dye (methyl red), with maximum adsorption quantity of 10.8 and 17.6 mg/g, respectively. The established preparative strategy can be potentially extended to other renewable phenylpropenes and MAH derivatives, and also can be taken as a versatile platform for fabricating biobased polymeric microspheres. Apart from being potentially used as adsorbents toward diverse adsorbates (metal ions, organic compounds, etc.), the microspheres also can be further explored as biomaterials, emulsifiers, among others.