PurposeThe present work aims to prepare biocomposites blend based on linear low density polyethylene/ starch without using harmful chemicals to improve the adhesion between two phases. Also, the efficiency of essential oils as green plasticizers and natural antimicrobial agents were evaluated.Design/methodology/approachBarrier properties and biodegradation behavior of linear low density polyethylene/starch (LLDPE/starch) blends plasticized with different essential oils including moringa oleifera and castor oils wereassessed as a comparison with traditional plasticizer such as glycerol. Biodegradation behavior forLLDPE/starch blends was monitored by soil burial test. The composted samples were recovered then washed followed by drying, and weighting samples after 30, 60, and 90 days to assess the change in weight loss. Also, mechanical properties including retention values of tensile strength and elongation at break were measured before and after composting. Furthermore, scanning electron microscope (SEM) was used to evaluate the change in the morphology of the polymeric blends. In addition to, the antimicrobial activity of plasticized LLDPE/starch blends films was evaluated using a standard plate counting technique.FindingsThe results illustrate that the water vapor transition rate increases from 2.5 g m-2 24 h-1 for LLDPE/5starch to 4.21 g m-2 24 h-1 and 4.43 g m-2 24 h-1 for castor and moringa oleifera respectively. Also, the retained tensile strength values of all blends decrease gradually with increasing composting period. Unplasticized LLDPE/5starch showed highest tensile strength retention of 91.6% compared to the other blends that were 89.61, 88.49 and 86.91 for the plasticized LLDPE/5starch with glycerol, castor and M. oleifera oils respectively. As well as, the presence of essential oils in LLDPE/ starch blends increase the inhibition growth of escherichia coli, candida albicans and staphylococcus aureus.Originality/valueThe objective of this work is to develop cost-effective and environmentally-friendly methods for preparing biodegradable polymers suitable for packaging applications.

In this paper, pectin-based plastic films were developed by grafting vanillin to pectin chains and introducing Fe3+ ions. The mechanical properties, thermal stability, moisture resistance, UV-light barrier property, biodegrad-ability, and practical application of fabricated plastic film were evaluated. Results confirmed the successful grafting of vanillin and the presence of hydrogen bonds and metal-ligand bonds, giving the plastic film highest fracture stress of 41.68 +/- 4.10 MPa, which was nearly 481.31% enhancement than that of neat pectin film. Additionally, the thermal stability, moisture resistance, and UV-blocking property (200-400 nm) of fabricated plastic film were significantly improved. Moreover, the plastic film exhibited satisfying processability, which can be processed to bag and appearing excellent food preservation ability. After use, the plastic film can be completely biodegradable in soil (degradation time approximate to 7 weeks) and seawater without manual interference. Thus, our proposed pectin-based plastic film can be recommended as a non-polluting and sustainable food packaging substitute.

The challenge of global climate change has drawn people's attention to the issue of carbon emissions. Reducing the use of petroleum-derived materials and increasing the use of biodegradable materials is a current focus of research, especially in the packaging materials industry. This study focused on the use of environmentally friendly plastics and waste paper as the main materials for packaging films. Poly(butylene succinate-co-lactate) (PBSL) was modified with maleic anhydride (MA) to form a biobased compatibilizer (MPBSL), which was then blended with a mixture (WPS) of waste-paper powder (WP) and silica aerogel powder (SP) to form the designed composite (MPBSL/WPS). The modification of PBSL with MA improved interfacial adhesion between PBSL and WPS. The structure, thermal, and mechanical properties, water vapor/oxygen barrier, toxicity, freshness, and biodegradability of MPBSL/WPS films were evaluated. Compared with the PBSL/WP film, the MPBSL/WPS film exhibited increased tensile strength at break of 4-13.5 MPa, increased initial decomposition loss at 5 wt% of 14-35 degrees C, and decreased water/oxygen permeabilities of 18-105 cm(3)/m(2)dPa. In the water absorption test, the MPBSL/WPS film displayed about 2-6 % lower water absorption than that of the PBSL/WP film. In the cytocompatibility test, both MPBSL/WPS and PBSL/WP membrane were nontoxic. In addition, compared with PBSL/WP film and the control, the MPBSL/WPS film significantly reduced moisture loss, extended the shelf life, and prevented microbial growth in vegetable and meat preservation tests. Both MPBSL/WPS and PBSL/WP films were biodegradable in a 60-day soil biodegradation test; the degradation rate was 50 % when the WP or WPS content was 40 wt%. Our findings indicate that the composites would be suitable for environmentally sustainable packaging materials.