The contribution reports the first polymeric microspheres derived from a biomass, vanillin. It reacted with methacryloyl chloride, providing monomer vanillin methacrylate (VMA), which underwent suspension polymerization in aqueous media and yielded microspheres in high yield (>90 wt %). By controlling the N2 bubbling mode and by optimizing the cosolvent for dissolving the solid monomer, the microspheres were endowed with surface pores, demonstrated by SEM images and mercury intrusion porosimetry measurement. Taking advantage of the reactive aldehyde groups, the microspheres further reacted with glycine, thereby leading to a novel type of Schiff-base chelating material. The functionalized microspheres demonstrated remarkable adsorption toward Cu(2+) (maximum, 135 mg/g) which was taken as representative for metal ions. The present study provides an unprecedented class of biobased polymeric microspheres showing large potentials as adsorbents in wastewater treatment. Also importantly, the reactive aldehyde groups may enable the microspheres to be used as novel materials for immobilizing biomacromolecules, e.g. enzymes.

A novel type of hollow polymer particles containing carboxyl groups was prepared from a widely available biophenylpropene trans-anethole (ANE). To prepare the hollow particles, we first prepared polymeric particles using vinyl acetate and maleic anhydride (MAH), and then such particles were taken as sacrificial templates for the subsequent formation of core/shell particles, which were synthesized by using ANE and MAH as comonomers and divinylbenzene (DVB) as cross-linking agent through precipitation polymerization. After removing the core in the prepared core/shell particles, we obtained hollow particles and then hydrolyzed the anhydride groups into carboxyl functional groups. The hollow particles were characterized by FT-IR, SEM, and TEM, and further used as absorbents. The maximum adsorption toward Cu 2+ and methylene blue reached 270 and 940 mg/g, respectively. The recycling study showed that the biobased hollow particles can be easily restored and reused. The hollow particles may find practical applications as sustainable absorbents. The established methodology for preparing hollow polymer particles is expected to be applicable for other biophenylpropenes.

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Amorphous nonconjugated room-temperature phosphorescent (RTP) polymers have aroused ever-increasing attention. However, the variety of such polymers is still rare due to limited preparation strategies. Herein, we report a facile strategy to achieve ultralong RTP emission in biobased nonconjugated polymers through a hydrolyzation process. The investigated polymers are synthesized by free radical solution copolymerization using biomass methyl isoeugenol and maleic anhydride as monomers. Noticeably, the obtained polymers carry no conventional fluorescent units but can exhibit blue fluorescence. More interestingly, after hydrolysis in sodium hydroxide aqueous solution, the resulting hydrolyzed polymers emit both enhanced blue emission and persistent RTP (up to 400 ms) under air conditions, with reversible emission performance switched via the uptake and removal of water. Also worthy to be highlighted is that the emission can be remarkably regulated by the cations in carboxylate or the substituents on the benzene ring. The as-obtained polymers demonstrate potential applications in anticounterfeiting and information encryption.

The importance of chiral compounds has been widely recognized. Enantioselectively controlled release of the desired enantiomer from a racemate while retarding the other isomer provides a novel route toward practical applications of biologically chiral molecules. Such processes may maximize the efficacy while minimizing the dosage and frequency of chiral compounds. So far, exciting achievements have been made in enantioselective release (ESR), which can be classified into two main groups according to the essential strategy: (1) chiral interactions occurring between chiral compounds and chiral matrices (“enantioselective interaction” strategy); and (2) recognizing sites inside molecular-imprinting polymers (MIPs; “key-to-lock” strategy). The chiral compounds of interest are not limited to chiral drugs, but also include other biologically important chiral compounds (e.g., amino acids). Based on our studies, this article reviews the state-of-the-art techniques and materials systems toward ESR. The emphasis is placed on the materials and material systems established for the ESR purpose.