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The antibacterial performance of biocomposite films prepared from lignocellulosic waste (hazelnut husk or hazelnut leafy green cover) modified with silver nanoparticles and polylactic acid (PLA) was determined. The amount of hazelnut husk in the PLA matrix ranged from 10 to 40% by weight in 10% increments. The composite pellets were produced using a twin-screw extruder. Biocomposite films of 0.6 mm x 40 mm x 200 mm were produced from the pellets in a laboratory hydraulic hot press. The surfaces of the modified hazelnut husk and biocomposite specimens were analyzed by scanning electron microscopy (SEM) and inductively coupled plasma optical emission spectrometry (ICP-OES). The antibacterial activity of the biocomposite films against Staphylococcus aureus bacteria was determined using the ASTM E 2149 (2020) method. The antibacterial activity of the biocomposite films increased noticeably with the addition of hazelnut husk modified with the silver nanoparticles. Compared to the pure PLA film, the biocomposite films with 10 wt% modified husk flour showed the lowest antibacterial activity (31.3%) against S. aureus over 24-h while the films with 40 wt% showed the highest antibacterial activity (99.9%). The biocomposite films made of hazelnut husk flour with silver nanoparticles and PLA matrix could be considered for food packaging applications. [ABSTRACT FROM AUTHOR]

This study focused on the potential use of hazelnut husk (HH) flour, agricultural by-product, as filler in the PLA biocomposite films. The tensile strength and elongation at break of the biocomposites films decreased with the increasing content of the HH flour. As the amount of the HH flour in the PLA was increased by 10 wt%, the tensile strength decreased from 33 to 26.3 MPa. A sharp decrease in the tensile strength (6.33 MPa) of the specimens was determined as the amount of the HH flour was increased by 20 wt%. There was no significant difference in the tensile strength as the HH content increased from 20 to 40 wt%. The main reason for the lower tensile strength was mainly attributed to them due to the weak interfacial bond between HH flour with higher polar surface and the PLA with lower polar surface. The hydrophilic nature of the HH leads to a tendency for HH fibers to mingle or form agglomerations, which resulted in the lower tensile strength, especially at high HH filler loadings. The increase in the filler content improved the thermal stability of biocomposites. [ABSTRACT FROM AUTHOR]

Next-generation laminated wood composites were produced using waste poplar (Populus deltoides) veneer and polyvinyl acetate adhesive. Four experimental groups and one control group were created. Ten-layer laminated wood veneer samples were reinforced with natural rubber (Group A), linoleum (Group B), felt (Group C), and elastomeric sponge (Group D); these materials were used in the fifth adhesive layer (middle layer). The sound absorption coefficients of the control and experimental groups were tested via the impedance tube method, according to ASTM standard E1050 (2006). Attention was paid to the acoustic behavior at low frequencies (63 Hz to 250 Hz), mid frequencies (250 Hz to 2000 Hz), and high frequencies (2000 Hz to 6300 Hz). It was determined that the sound absorption coefficient of the experimental groups considerably increased. It can be suggested that the experimental groups be used as sound absorbing acoustic panels and the control group as sound reflective acoustic panels. [ABSTRACT FROM AUTHOR]