Polydiacetylene-Based Smart Packaging. In: Tunick MH, Onwulata CI, editors. Physical Methods in Food Analysis. Washington: American Chemical Society; 2013. pp. 137-54. [DOI: 10.1021/bk-2013-1138.ch010]

Polydiacetylene-Perylenediimide Supercapacitors

Organic supercapacitors have attracted interest as promising "green" and efficient components in energy storage applications. A polydiacetylene derivative coupled with reduced graphene oxide was employed, for the first time, to generate an organic pseudocapacitance-based supercapacitor that exhibited excellent electrochemical properties. Specifically, diacetylene monomers were functionalized with perylenediimide (PDI), spontaneously forming elongated microfibers. Following polymerization through UV irradiation, the PDI-polydiacetylene microfibers were interspersed with reduced graphene oxide (rGO), generating a porous electrode material exhibiting a high surface area and facilitating efficient ion diffusion, both essential preconditions for supercapacitor applications. We show that PDI-polydiacetylene has an important role in enhancing the electrochemical properties as a supercapacitor electrode. Besides stabilizing the microporous electrode organization, the delocalized π electrons in both the PDI residues and conjugated network of the polydiacetylene contributed to a significantly higher capacitance (specific capacitance >600 F g^-1 at 1 A g^-1 current density), longer discharge time, and high power density. The PDI-polydiacetylene-rGO electrodes were employed in a functional supercapacitor device.

Responsive Food Packaging: Recent Progress and Technological Prospects

Responsive food packaging is an emerging field in food packaging research and the food industry. Unlike active packaging, responsive packaging systems react to stimuli in the food or the environment to enable real time food quality and food safety monitoring or remediation. This review attempts to define and clarify the different classes of food packaging technologies. Special emphasis is given to the description of responsive food packaging including its technical requirements, the state of the art in research and the current expanding market. The development and promises of stimuli responsive materials in responsive food packaging are addressed, along with current challenges and future directions to help translate research developments into commercial products.

Stereoselective Iterative Convergent Synthesis of Z-Oligodiacetylenes from Propargylic Dithioacetals

A series of (t)Bu-substituted Z-oligodiacetylenes (Z-ODAs) are synthesized from the reactions of allenyl/propargylic zinc reagents, obtained from the corresponding propargylic dithiolanes and BuLi, with dithiolane-substituted propargylic aldehydes followed by stereospecific elimination of β-thioalkoxy alcohols under Mitsunobu conditions. The stereochemical assignments are based on NOE experiments. The X-ray structure of the hexamer further supports the Z configuration for each of the double bonds in these ODAs. The photophysical properties of these Z-ODAs have been examined and are compared with known related E- and Z-ODAs with different substituents.