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Epoxy-based thermosets are one of the most popular matrix materials in many industries, and significant environmental benefits can be obtained by developing a recyclable variant of this widely utilized material. Incorporation of a bio-based disulfide additive within a commercial epoxy system leads to a cross-linked material that can be fractionated under mild and environmentally benign conditions. The material has been analyzed by FTIR and solid-state NMR. Furthermore, modified epoxy matrices with low additive concentrations are demonstrated to have similar mechanical and thermal properties compared to commercially available benchmarks. Thus, additive formulation and fractionation based on green chemistry principles have been demonstrated, and a recyclable epoxy matrix has been developed.

This work is an initial investigation of the possible use of redox-active anthraquinone as anode material in combination with Ni­(OH)2 in a secondary battery with aqueous KOH electrolyte. Three different anode materials are investigated: an anthraquinone monomer and two different anthraquinone based oligomers. All batteries are rechargeable, and almost 100% of the theoretical capacity can be accessed in the first cycle, after which significant capacity loss occurs. The capacity loss is attributed mainly to swelling of the electrodes and solubility of anthraquinones in their charged (reduced) state because reduced anthraquinone is deprotonated and ionized in alkaline solutions. Nonetheless, batteries based on one of the oligomerized anthraquinones (oligo­[benzene-1,4-dithiol-alt-(1,5- dichloroanthraquinone)] anode) show the best performance and retain almost 50% of the discharge capacity after 100 cycles. The better performance is attributed to the reduced solubility caused by the oligomerization. It is anticipated that measures to decrease the solubility further could lead to much improved capacity retention.

Self-immolative polymers (SIPs) are a class of degradable polymers that upon exposure to specific stimuli will degrade into small monomer-like products. The polymer poly­(dithiothreitol) (pDTT) has been shown to behave as a SIP, but expanding its practical use in various applications requires adjustment of its chemical functionalities and physiochemical properties. To address this, we report the use of Steglich esterification as a versatile synthetic method for the postpolymerization modification of pDTT. In this manner, we were able to introduce various side groups to the self-immolative backbone with a wide variety of pendant groups, including saturated, unsaturated, and halogenated alkyl groups, let alone aromatic and heteroaromatic groups. In general, Steglich esterification proceeds with both high yields and full conversions of hydroxyl groups in the polymer. The chemical modification changes significantly both the physiochemical behavior and processability of the SIPs. In addition, depolymerization of pDTT containing the pendant anthraquinone group can be electrochemically triggered.

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