High-pressure autohydrolysis process of wheat straw for cellulose recovery and subsequent use in PBAT composites preparation

Valorization of wheat straw in food packaging: A source of cellulose

Wheat straw (WS) is one of the abundant categories of agricultural waste, which is usually abandoned and burned yearly, thus creating environmental issues. Traditionally, it is used for low-value purposes, mainly in cattle feeding or agricultural mulch, and the rest is burnt or thrown away. WS is a valuable candidate as raw material for being used as reinforcing fibers to fabricate biocomposites. Among existing strategies, one of the potential strategies to utilize such lignocellulosic biomasses includes the extraction of cellulose as a potential candidate in the fabrication of sustainable packaging. Exploring WS as a valuable source of cellulose could be a key strategy for enabling biopolymers in packaging, which relies on developing tailor-made materials from non-food and low-cost resources. In this regard, the valorization of WSs for packaging can add value to these underutilized residues and successfully contribute to the circular economy concept. The review addresses the valorization of WS as a source of cellulose and its nanostructured forms for food packaging applications. The review also discusses cellulose derivatives extraction using conventional or innovative techniques (microwave-assisted extraction, fractionation, mechanical fibrillation, steam-explosion, microfludization, enzymatic hydrolysis, etc.). The different applications of these extracted biopolymers in the packaging are also summarized.

Simulated Environmental Conditioning of PHB Composites Reinforced with Barley Fibres to Determine the Viability of Their Use as Plastics for the Agriculture Sector

Nowadays, the search for new materials with a sustainable character to reduce the production of residues is under continuous research. In this sense, fully biodegradable composites based on polyhydroxybutyrate and different pretreated fibres coming from barley straw have been fabricated, and their resistance to environmental controlled conditions have been characterized. The materials were already compounded in a kinetic mixer and injection-moulded as specimens for tensile assay to be aged in a Xenotest chamber so as to simulate environmental conditioning. The samples, after accelerated aging, were characterized thus: mechanical characterization (tensile assay), water uptake (immersion and contact angle), and surface observation (optical and SEM microscopy). The incorporation of the fibres helps the composite to keep its structure for a longer time. On the other hand, the presence of the fibres increases the water uptake capacity to allow water permeation in the composite, which allows final degradation, characterised by a significant drop in properties after one month of exposure to simulated environmental conditions.

Compostable Packaging Waste Management—Main Barriers, Reasons, and the Potential Directions for Development

The paper aims to identify the main reasons for the low level of compostable packaging waste management and to propose potential directions for development. Based on qualitative research (individual in-depth interviews and focus group discussions using the Social Innovation Lab), these are: (1) the lack of uniform and transparent regulations regarding the planning and organization of a closed-loop system for compostable packaging, (2) insufficient communication between the private and public sectors on how to increase the use of compostable packaging, (3) poorly developed infrastructure for compostable waste recycling, and (4) a lack of financial incentives to support activities for the circular economy of composting packaging at the communal level. Moreover, the portfolio of bottom-up (initiated by consumers, educational institutions, and NGOs) and bottom-down dimension (national, regional programs) proposals are presented. The diagnosis of different view perspectives of the supply chain underlines the crucial role of stakeholder cooperation improvement.