Selective localization of graphene in co-continuous polymer blends is an attractive method for preparing conductive polymer composites. Localization of graphene at the interface between the two polymer phases produces good conductivity at ultra-low concentrations. Although graphene localization is ultimately dependent on thermodynamic factors such as the surface energy of graphene and the two polymer components, kinetics also strongly affects the migration and localization of graphene in polymer blends during melt compounding. However, few studies have systemically investigated the important role of kinetics on graphene localization. Here, we introduced graphene nanoplatelets (GNPs) in polylactic acid (PLA)/polystyrene (PS) co-continuous polymer blends. Although GNPs in thermal equilibrium prefer the PS phase, we were able to kinetically trap GNPs at the interface of polymer blends via control of melt-compounding sequences, mixing times and shear rates. Utilizing morphological, rheological, and electrical measurements, we verified graphene localization and the suppression of coarsening in co-continuous polymer blends during annealing. When GNPs were premixed with the thermodynamically less-favorable PLA phase before mixing with the PS phase, GNPs can be kinetically trapped at the interface during melt compounding. Moreover, we show that a shorter melt-compounding time gives rise to a higher GNP interfacial coverage and a more effective morphology stabilization effect. Blends with as low as 0.5 wt % GNPs with only 30 s of melt compounding have a room-temperature conductivity of ∼10 S/cm, which is larger than blends with longer melt-compounding times and potentially useful for antistatic materials. The in-depth study on the kinetics of graphene localization in our work provides a general guideline for the kinetic control of the localization of platelike nanofillers in polymer blends. Our study also demonstrates a facile method for manufacturing conductive polymer blends with low percolation thresholds.

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Commiphora wightii based bioactive edible film was developed for the preservation of meat products. Maltodextrin and alginate-based edible films were developed using different levels of C. wightii namely, 0.25% (T 1 ), 0.50% (T 2 ), 0.75% (T 3 ) and 0.0% (control) and were characterized (thickness (mm), solubility (%), transparency and moisture content (%)) and assessed for their efficacy for improving the storage quality of meat products during refrigerated storage using chicken nuggets as a meat model system. The chicken nuggets were wrapped in the edible films, packaged under vacuum, and stored at refrigeration temperature (4 ± 1 C) for 60 days. The samples were taken on 0, 15, 30, 45 and 60th day and evaluated for various storage quality parameters. Addition of C. wightii increased (p < .05) total phenolic (mg/g Gallic acid equivalents) and total flavonoid contents (mg/g Quercetin equivalents) and reduced free fatty acids (% oleic acid), TBARS (mg malondialdehyde/kg) and microbial counts [total plate, psychrophilic, yeast/mold, and anaerobic counts (log 10 cfu/g)] while improving the sensory quality of the products. Addition of C. wightii increased (p < .05) the thickness (mm), opacity and moisture content (%) whereas decreased the solubility (%) of the films. The C. wightii based edible film significantly (p < .05) improved the lipid oxidative and microbial stability of the model meat product during refrigerated storage. The present results suggest that C. wightii based edible film can be used commercially in the meat industry for improving the storage quality of the meat products. | INTRODUCTIONCommiphora wightii is a safe medicinal plant with several pharmaceutical and therapeutic applications and is used for cholesterol reduction, hyperlipidemia, atherosclerosis and coronary artery disease (Saini, Rajput, Rathore, & Tomar, 2018). The plant extract has antioxidant, antimicrobial, and antiinflammatory properties and contains several active ingredients such as flavonoids, monoterpenoids, diterpenoids,