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This study investigated the effects of different processing techniques and sol-gel coating on the physical properties of biocomposite material. Two dispersion series from corn starch, clay, and sorbitol were prepared by conventional and microwave-assisted processing, and casting technique. One film from each series was sol-gel coated by immersion. All the samples were subjected to moisture content (MC), water solubility (WS), water absorption (WA), FT-IR, DSC, and SEM/digital microscopy tests. The results showed that the coated films contained higher MC (11.5±0.5%) than the non-coated films (5.3±0.6%) and absorbed less water (44.7±12.4%), compared to the non-coated ones (166.3±2.5%). Non-coated films exhibited less solubility in water (26.1±0.2%) than the coated ones (51.0±0.7%). FT-IR test detected cross-linking (1723 cm-1 ester) in the microwave-assisted coated film. The sol-gel coating increased the latent heat of melting and specific heat values by 14.9% and 19.4% for conventionally fabricated samples, and 22.3% and 25.3% for microwaved films, respectively, whereas it reduced the temperature of melting by 23.1% for conventionally fabricated ones, and 6.6% for microwaved ones. Microscopic tests revealed that microwaved compact morphology indicated better gelatinization of starch. Overall, microwaving and sol-gel coating need further investigation to improve the physical properties of biocomposite materials for food packaging.

To eliminate contaminated organic matter from water and wastewater, a stable, recyclable, and environmentally friendly nano-biocomposite was designed. The magnetic Fe3O4 nanoparticles were functionalized by SiO2/N-2-(aminoethyl)-3-aminopropyl/glutaraldehyde/chitosan/Cobalt to fabricate nano-biocomposite (FS-(Am/g/Cs)@CoNPs). The morphological/structural identification of nano-biocomposite was carried out by ICP-OES, DR-UV, XRD, FE-SEM, TEM, HR-TEM, BET, EDX, FT-IR, TGA, and VSM techniques. The catalytic performance of this heterogeneous catalyst was studied in the degradation of organic dyes including methylene blue, methyl orange, methylene violet, and Bisphenol A, and efficiency was achieved at 99.3 % (kobs = 0.3703 min−1), 97.4 % (kobs = 0.3627 min−1), 93.6 % (kobs = 0.228 min−1) and 98.8 % (kobs = 0.459 min−1) after 12–14 min at room temperature in pH = 7.0, respectively. The reaction proceeded through the activation of Co2+/Co3+ which occurs on the surface of the FS-(Am/g/Cs)@CoNP by the PMS/O2 system through recombination of SO4•- and OH•. Furthermore, selective allylic oxidations of cyclohexene to cyclohexenone (TOF = 4583.7 h−1, 100 % selectivity, 98 % conversion) were done by this nano-biocomposite.

Abstract A novel, promising biocomposite was synthesized through the free radical polymerization method using methyl methacrylate (MMA), acrylic acid (AA), and hydroxyapatite derived from oyster shells (Os‐HA). Fourier transform infrared spectroscopy (FTIR) peaks indicate the conjugation of Os‐HA in the biocomposite. From the TGA analysis, it was observed that a weight loss of nearly 2% is achieved at 210°C, up to 15% at 210 to 420°C, and up to 95% at 420 to 580°C. The SEM image shows the uniform dispersion of the Os‐HA particles and strong interaction with the copolymer matrix. The broad spectrum at 2θ = 14.6° in XRD analysis indicates the amorphous nature of poly(MMA‐co‐AA)/Os‐HA. The higher inhibition zone of the biocomposite is observed at 125 μL against E. coli bacteria. The maximum water absorption is observed at 15 wt% of Os‐HA. The young's modulus gradually increases, while the impact strength decreases up to 20 wt% of Os‐HA. The artificial neural network (ANN) model has been used to assess the optimum values of impact strength, tensile strength, and Young's modulus of the biocomposite material. The correlation factor (R = 0.998) of the ANN model data indicates greater accuracy of the experimental result.

The field of hybrid engineered living materials seeks to pair living organisms with synthetic materials to generate biocomposite materials with augmented function since living systems can provide highly-programmable and complex behavior. Engineered living materials have typically been fabricated using techniques in benign aqueous environments, limiting their application. In this work, biocomposite fabrication is demonstrated in which spores from polymer-degrading bacteria are incorporated into a thermoplastic polyurethane using high-temperature melt extrusion. Bacteria are engineered using adaptive laboratory evolution to improve their heat tolerance to ensure nearly complete cell survivability during manufacturing at 135 °C. Furthermore, the overall tensile properties of spore-filled thermoplastic polyurethanes are substantially improved, resulting in a significant improvement in toughness. The biocomposites facilitate disintegration in compost in the absence of a microbe-rich environment. Finally, embedded spores demonstrate a rationally programmed function, expressing green fluorescent protein. This research provides a scalable method to fabricate advanced biocomposite materials in industrially-compatible processes.

The emerging interests in high-performance biocomposites grows significantly driven by their superior environmental sustainability. This study proposes a unique biocomposite strategy by implementing an acetic and ball-milled treatment to disrupt the bamboo cell wall structure, thereby facilitating further processing by effectively increasing the active sites and specific surface area in the bamboo fiber. The fibers are subsequently carboxymethylated to introduce carboxyl groups which facilitate physical bonding between the fibers and Mg2+ ions that are added to the system. These ions form metal-coordination bonds with the carboxyl groups, acting as ion bridges that significantly strengthen the inter-fiber bonding. The resulted biocomposite exhibits impressive mechanical properties, including a high tensile strength (94.24 MPa) and flexural strength (104.14 MPa), not only that, changes in elastic modulus also highlight changes in fiber bonding, the flexural modulus is 21.29 GPa and the tensile modulus is 7.01 GPa. Moreover, it maintains a low water uptake capacity of only 6.8 % despite being submerged for 12 h. The thermal conductivity and fire retardancy have also been improved. The synergic bonding ability between the cellulose and lignin in the fibers, coupled with the glue-free thermoforming process, enhances the material performance and renders it fully recyclable, thus reducing environmental pollution and providing cost-effective engineering materials to society.

The adsorbent is typically used in the form of a fine powder, which can pose challenges when attempting to recover from the liquid after use. This issue has been addressed by encapsulating the fine powder in a biopolymeric material to create a biocomposite film. In this study, activated carbon (AC) powder derived from microalgal biomass and pectin were used to produce this biocomposite film. This film was employed as an adsorbent to remove basic yellow 1 (BY) dye from a liquid solution. The biocomposite film underwent characterization using a gas sorption analyzer, Fourier transform infrared spectrometry, and field emission scanning electron microscopy. The point of zero charge and mechanical properties were also determined. The impact of various factors, including contact time, initial pH, initial dye concentration, and temperature, on BY uptake were investigated. The BY uptake reached equilibrium at 540 min, and the monolayer BY uptake was 57.75 mg/g. Experimental design and response surface methodology were utilized to identify the key factors affecting BY uptake and determine the optimal levels of these factors for maximum BY uptake. Statistical analysis of the derived model yielded an R2 of 0.9997 and a p-value of 9.89 × 10−5, indicating that the optimal conditions were achieved under specific conditions: a solution pH of 2.0, an initial BY concentration of 250 mg/L, and operating temperature of 320 K. These results suggest that the low-cost biocomposite film developed in this study has the potential to effectively remove BY from industrial wastewater.