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ABSTRACT Multilayer packaging is commonly used in the food industry to improve product preservation by combining materials with specific properties for optimal protection. Ethylene vinyl alcohol (EVOH) is highly valued for its barrier properties against air and moisture. The mechanical properties of EVOH films are influenced by both the ethylene content, which affects crystallinity and barrier performance, and the thickness of the EVOH layer, which affects the film's mechanical strength. This study develops mathematical models to explore the relationship between EVOH film thickness, ethylene content, and mechanical properties, such as tensile strength, elongation at break, and elastic modulus. Using RSM with I‐optimal design, the optimal conditions for EVOH films are identified at a thickness of 0.03 mm and 48 mol% ethylene content. The model predicts values of 25.178% for elongation at break, 3077.865 MPa for elastic modulus, and 97.444 MPa for tensile strength. These predictions are validated through ANOVA, confirming the statistical significance of the model. Experimental results show achieved values of 27.119% for elongation, 3437.811 MPa for elastic modulus, and 107.308 MPa for tensile strength, demonstrating model accuracy. To further validate these findings, EVOH films are characterized by SEM, FTIR spectroscopy, and TGA, providing valuable insights into the structural and functional properties for food packaging. 

Abstract Major limitation for use of epoxy thermosets in engineering applications is its sudden brittle failure. In the present study dipropylene glycol dibenzoate (DPGDB) based plasticizer is used to modify diglycidyl ether of bisphenol A (DEGEBA) based epoxy resin system via simple blending technique. Bio‐based epoxidized linseed oil was also used to modify epoxy resin system and compared with DPGDB modified resin. For DPGDB modified resin storage modulus and loss modulus of the epoxy system modified with 10% plasticizer increased by 7.54% and 12.24%, respectively. The primary mechanism responsible for such behavior is improved crosslinking density. With 5% plasticizer loading, flexural strength increased by 21%. There was an improvement of 312.74% in strain at failure for 10% plasticizer loading, while preserving its mechanical strength. It was found that DPGDB based modification was better than epoxidized linseed oil modification. 

Abstract Forcespinning technique was used to fabricate sub-micron size polycaprolactone (PCL) fibers. Forcespinning method uses centrifugal forces for the generation of fibers unlike the electrospinning method which uses electrostatic force. PCL has been extensively used as scaffolds for cell regeneration, substrates for tissue engineering and in drug delivery systems. The aim of this study is to qualitatively analyze the force spun fiber mats and investigate the effect of the spinneret rotational speed on the fiber morphology, thermal and mechanical properties. The extracted fibers were characterized by scanning electron microscopy differential scanning calorimetry, tensile testing and dynamic mechanical analysis. The results showed that higher rotational speeds produced uniform fibers with less number of beads. The crystallinity of the fibers decreased with increase in rotational speeds. The Young’s modulus of the forcespun fibers was found to be in the range of 3.5 to 6 MPa. Storage and loss moduli decreased with the increase in the fiber diameter. The fibers collected at farther distance from spinneret exhibited optimal mechanical properties compared to the fibers collected at shorter distances. This study will aid in extracting fibers with uniform geometries and lower beads to achieve the desired nanofiber drug release properties. 

Cellulose is an important structural material found naturally within the cell walls of plants that has recently been researched as a biodegradable, renewable, and non-toxic reinforcing agent used to improve properties for a variety of composite systems. Cellulose is usually derived from wood sources via acid hydrolysis. Bacterial cellulose (BC) is produced by bacteria proliferation using nitrogen, carbon, and oxygen sources, and is similar chemically to plant extracted cellulose. Compared to commercially available cellulose, BC has higher purity and increased hydrophilicity. In this work, banana peels are used as a carbon source for bacterial cellulose growth. The peels were heat treated to maximize sugar and carbon contents. In addition, BC derived from the banana peels doesn’t require any bleaching or chemical post-processing. In this research, BC derived from banana peels is synthesized, characterized, and analyzed for its physical, mechanical, and thermomechanical properties, as compared to commercial nanocellulose. 

The growing environmental concerns associated with petrochemical-based adhesives have driven interest in sustainable alternatives. This study investigates the use of bio-oil, derived from municipal sewage sludge (MSS) through hydrothermal liquefaction (HTL), as a reactive filler in polymeric methylene diphenyl diisocyanate (pMDI) wood adhesives. The bio-oil, rich in hydroxyl and carbonyl functional groups, was characterized using FTIR (Fourier transform infrared spectroscopy), elemental analysis, and NMR (nuclear magnetic resonance). These functional groups interact with the isocyanate groups of pMDI, enabling crosslinking and enhancing adhesive performance. Various MSS bio-oil and pMDI formulations were evaluated for tensile shear strength on Southern yellow pine veneers under dry and wet conditions. The formulation with a 1:4 bio-oil to pMDI weight ratio exhibited the best performance, achieving tensile shear strengths of 1.96 MPa (dry) and 1.66 MPa (wet). Higher bio-oil content led to decreased adhesive strength, attributed to reduced crosslinking and increased moisture sensitivity. This study demonstrates the potential of MSS-derived bio-oil as a sustainable additive in pMDI adhesives, offering environmental benefits without significantly compromising adhesive performance and marking a step toward greener wood adhesive solutions.