Optically active polymer particles constitute a unique type of polymer particle. However, nearly all the particles of this kind so far reported in the literature were prepared from chiral monomers. On the other hand, helix-sense-selective polymerization (HSSP) techniques were majorly applied in solution polymerization systems for preparing helical polymers adopting predominant onehanded helicity. In the present study, we report the first HSSP in precipitation polymerization systems, by which optically active helical polymer particles were constructed from an achiral monomer. Achiral acetylenic monomer with bulky adamantyl group smoothly underwent helix-sense-selective precipitation polymerization (HSSPP) with (nbd)Rh + B − (C 6 H 5 ) 4 as catalyst in the presence of Boc-L-or Boc-D-alanine as chiral additive. The HSSPPs provided optically active polymer particles consisting of helical polymer forming predominantly one-handed screw sense. SEM images show that the resulting polymer particles were obtained in high yield (80 wt %, average diameter approximately 300 nm) with regular spherical morphology. CD spectra clearly demonstrated that HSSP occurred in the course of precipitation polymerizations. The induced helical structures with preferential screw sense exhibited relatively high thermostability. We further proposed a possible mechanism for the occurrence of HSSPPs and the formation of stable helical structures: Double hydrogen bonds formed between each chiral additive molecule and the neighboring two amide structures in the polymer pendant groups; the double hydrogen bonds played essential roles for controlling the screw sense of the helical polymer chains and the stability. Based on this mechanism, a "chiral-lock effect" was further put forward. The preparative strategy opens new routes for preparing optically active polymer particles and even novel superhelical architectures for significant uses as chiral stationary phase for HPLC, chiral catalysts, enantioselective recognition probes, etc.

This paper reports the first biobased microspheres derived from phenylpropenic resources. To explore the potentials of biomass derived trans-anethole (ANE) and to develop new biobased polymeric materials, ANE was used for preparing an unprecedented kind of polymeric microspheres constructed by poly­(trans-ANE-co-maleic anhydride) [poly­(ANE-co-MAH)] through free radical precipitation polymerization in methyl ethyl ketone/n-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.

Biobased polymers have gathered a lot of interest and are currently attracting ever‐increasing attention. However, polymeric microspheres especially those derived from biomasses of small molecules, have not been extensively explored yet. This contribution reports recent exciting success in designing and preparing methyl isoeugenol (MeIE)‐derived renewable microspheres. Owing to the difficulty in homopolymerizing MeIE, it undergoes precipitation copolymerization with maleic anhydride to form the anticipated copolymeric microspheres in a high yield (both cross‐linked and non‐cross‐linked). The copolymers show high heat resistance, and the microspheres can be easily functionalized by taking advantage of the highly reactive anhydride groups. A novel type of cation exchange microspheres is further prepared by transforming the anhydride groups into carboxyl groups through hydrolyzation. The hydrolyzed microspheres demonstrate remarkable adsorption toward Cu2+ (maximum, 300 mg g−1). Accordingly, the microspheres may find practical applications, e.g., as green adsorbents. The established preparing methodology can also be taken for other bio‐phenylpropenes.