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High-performance and useful graphene oxide (GO) and cellulose nanocrystals (CNCs) are easily extracted from natural graphite and cellulose raw materials, and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is produced by bacterial fermentation from natural plant corn stalks, etc. In this study, novel ternary nanocomposites consisting of PHBV/ cellulose nanocrystal-graphene oxide nanohybrids were prepared via a simple solution casting method. The synergistic effect of CNC with GO nanohybrids obtained by chemical grafting (CNC-GO, covalent bonds) and physical blending (CNC/GO, noncovalent bonds) on the physicochemical properties of PHBV nanocomposites was evaluated and the results compared with a single component nanofiller (CNC or GO) in binary nanocomposites. More interestingly, ternary nanocomposites displayed the highest thermal stability and mechanical properties. Compared to neat PHBV, the tensile strength and elongation to break increased by 170.2 and 52.1%, respectively, and maximum degradation temperature (T max ) increment by 26.3 °C, were observed for the ternary nanocomposite with 1 wt % covalent bonded CNC-GO. Compared to neat PHBV, binary, and 1:0.5 wt % noncovalent CNC/GO based nanocomposites, the ternary nanocomposites with 1 wt % covalent bonded CNC-GO exhibited excellent barrier properties, good antibacterial activity (antibacterial ratio of 100.0%), reduced barrier properties, and lower migration level for both food simulants. Such a synergistic effect yielded high-performance ternary nanocomposites with great potential for bioactive food packaging materials.

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The aggregates of asphaltene and resin molecules play an important role in stabilizing heavy crude oil. Although many experiments are applied to investigate the complex aggregating structure of asphaltene and resin molecules in heavy crude oil, those microstructure and properties are still not clear at the molecular level. As another auxiliary tool, molecular dynamics (MD) simulation can be used to simulate the behavior of asphaltene and resin in the heavy oil droplet or emulsified oil droplet. The simulation results showed the following: (i) Asphaltene and resin molecules can form a netlike structure in heavy oil through face-to-face or edge-to-face stacking interaction, and the aggregating structure is considered to be the main reason that heavy crude oil has high viscosity. (ii) When surfactant molecules were added to the heavy oil phase, the asphaltene molecules moved to the center of emulsified oil droplet from the oil/water interface. The adsorption of surfactant molecules at the interface resulted in an increase in the hydrophilic surface area of the oil droplet. We think that the changed hydrophilicity of emulsified oil droplet is the key to the viscosity reduction of heavy oil. (iii) The steered MD simulation can prove that the interaction among asphaltene and resin molecules becomes fragile in emulsified heavy oil droplet, and it indicates that the added surfactant molecules are beneficial to the viscosity reduction in crude oil.