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The applications of phase change materials (PCMs) in some practical circumstances are currently limited due to the constant strong rigidity, poor thermal conductivity, and low photoabsorption property. Therefore, the design of flexibility-enhanced, highly efficient PCMs is greatly desirable and challenging. In this work, novel PCM composites (CPmG-x) with stable forms and thermally induced flexibility were successfully prepared by grafting the comblike poly-(hexadecyl acrylate) polymer (PA16, phase change working substance) onto a cellulose support by atom transfer radical polymerization (ATRP). Modified graphene (GN16) was incorporated into the synthesized material to enhance its enthalpy, thermal conductivity, and physical strength. The prepared CPmG-x composites exhibit excellent softness and flexibility after phase transition of PA16. The addition of GN16 increases the thermal conductivity and enthalpy of CPmG-x materials to 1.32 W m −1 K −1 (9 wt % GN16) and 103 J g −1 (5 wt % GN16), respectively. Assessments of the solar-to-thermal energy conversion and storage efficiencies indicate that CPmG-x composites possess great potential for use in thermal energy management applications and solar energy collection systems.

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Six model compounds having a 2-(1 H-pyrrolyl)carboxylic acid moiety and a hydrophobic R group were synthesized to study their effects on garlic greening, the structures of which are similar to that of 2-(3,4-dimethyl-1 H-pyrrolyl)-3-methylbutanoic acid (PP-Val) (a possible pigment precursor for garlic greening). The puree of freshly harvested garlic bulbs turned green after being soaked in solutions of all these compounds, and with both increasing concentrations and incubation time the green color of the puree became deeper. In contrast, neither pyrrole alone nor pyrrole combined with free amino acids had the ability to discolor the puree. The compounds exhibited a good relationship between structure and activity of garlic greening, namely, the smaller the size of the R group, the larger the contribution. Also, it was found that the unidentified yellow species can be produced by reacting the model compounds with pyruvic acid at room temperature (23-25 degrees C). Moreover, blue species were formed by incubation of the model compounds with di(2-propenyl) thiosulfinate at room temperature. On the basis of these observations, a pathway for garlic greening was proposed.