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Biodegradable polymers can be used for eco-friendly, functional, active packaging to preserve food quality. Incorporation of titanium dioxide (TiO2) nanoparticles into polymer packaging enhances ethylene-scavenging activity and extends the shelf-life of fresh produce. In this study, TiO2 nanoparticles were incorporated into biodegradable poly(butylene adipate-co-terephthalate) (PBAT)- and thermoplastic cassava starch (TPS)-blended films to produce nanocomposite packaging via blown-film extrusion. The effects of TiO2 on morphology, packaging properties, and applications as functional packaging for fresh produce were investigated. Increased TiO2 in the film packaging increased amorphous starch content and hydrogen bonding by interacting with the TPS phase of the polymer blend, with negligible chemical interaction with the PBAT component and identical mechanical relaxation in the PBAT phase. Surface topography indicated void space due to non-homogeneous dispersion causing increased oxygen and carbon dioxide permeability. Homogeneous dispersion of fine TiO2 nanoparticles increased mechanical strength and reduced oxygen, carbon dioxide, and water vapor permeability. Films containing TiO2 also showed efficient oxygen-scavenging activity that removed residual oxygen from the package headspace dependent on the levels and morphology of nanoparticles in the film matrices. Banana fruit packaged in films containing TiO2 recorded slower darkening color change and enhanced shelf-life with increasing TiO2 content.

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The main objective of this work is to study the effect of hydroxylamine sulfate or stabilizer states (solid vs liquid) on the storage hardening of natural rubber (NR). Several types of natural rubber samples were prepared: unstabilized NR samples and stabilized NR samples: (i) dry NR with 0.2 and 2.0 parts per hundred rubber (phr) of dry hydroxylamine sulfate, and (ii) natural latex with 0.2 and 2.0 phr of liquid hydroxylamine sulfate. The samples were characterized immediately (time 0) and after 12 weeks of storage at room temperature, respectively. We found that the Mooney viscosity, gel content, and Wallace plasticity of NR without a stabilizer increases with storage hardening for 12 weeks. However, two types of stabilized NR samples represent constant values of those three parameters, because hydroxylamine sulfate inhibits network and gel formation in NR. Interestingly, the mixing states (solid vs liquid) between natural rubber and the stabilizer affect the properties of stabilized NR. This could be explained by the better dispersion and homogeneous nature of liquid stabilizers in natural latex (liquid state), and thus the higher loading of the stabilizer in the liquid state. This is important, as the stabilization of NR properties as a function of time is required by rubber industry. This study is a utilization model from theory to application.

Hemp (Cannabis sativa Linn.) is a high-yielding annual crop farmed for its stalk fiber and oil-producing seeds. This specialized crop is currently experiencing a revival in production. Hemp fiber contains pectin, hemicellulose and lignin with superior strength, while hemp seed oil contains unsaturated triglycerides with well-established nutritional and physiological properties. Therefore, focus on the utilization of hemp in various industries is increasing globally. This study reviewed recent applications of hemp components, including fiber and extract, in food, textile and packaging applications. Hemp fibers mainly consisting of cellulose derivatives have superior strength to be used as reinforcements in thermoplastic packaging and paper. Combined physical and chemical modifications of hemp fibers improved mechanical and barrier properties of composite materials. Physically and chemically processed hemp extracts have been used in food and non-food applications. Functional foods containing hemp oils deliver nutrients by their unsaturated lipids. High-quality hemp fiber with several fiber modifications has been applied in garments. Innovative applications of hemp components and by-products are increasing, thereby facilitating utilization of green sustainable biomaterials.