Fecha de publicación: 16/11/2024 Fuente: Cellulose (Springer) Abstract
The increasing environmental concerns associated with the use of plastic foams in the food supply chain necessitate the exploration of alternative solutions. Among these, bio-foams derived from biodegradable raw materials have emerged as promising options. However, conventional methods for fabricating bio-foams with desirable properties often require specialized equipment, such as freeze-drying. Thus, this study presents a cost-effective and straightforward approach for fabricating bio-foam from recycled newspaper waste (ONP) that promotes low cost and eco-friendliness. This method involves mechanical water foaming, followed by simple oven drying. Citric acid (CA) was used as the crosslinking agent to enhance the stability and mechanical properties of the foam. By utilizing this technique, the developed ONP-CA-crosslinking composites bio-foams (ONP-CAs) have massive volume expansion of 333.17–673.50% compared to the control, low density of 9.23–15.16 kg/m3, and preferable mechanical strength up to 16.35 ± 0.61 kPa of compressive strength and 239.85 ± 20.13 kPa of compressive modulus which is comparable to the commercial plastic foam and bio-foams made from freeze drying technique. An optimum CA:ONP ratio that could enhance the properties of ONP-CAs was identified at 1.0; beyond this ratio, a brittle bio-foam formed. Furthermore, the obtained ONP-CAs contained thermal conductivity ranging from 0.035 to 0.037 W m⁻1 K⁻1, competitive with commercial thermal insulation material. The simplicity and cost-effectiveness of the fabrication process, as well as the eco-friendliness of the bio-foam, make it highly attractive for commercial upscale operations and a promising solution for sustainable packaging and insulation applications in the food supply chain.