We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Bio-based packaging foam: The effect of drying temperature on the properties of bio-based packaging foam
Original title: Biopohjainen pakkausvaahto: Kuivauslämpötilan vaikutus biopohjaisen pakkausvaahdon ominaisuuksiin
Summary
Scientists are developing plant-based packaging foam made from cellulose (wood pulp) as an alternative to plastic foams like Styrofoam, which shed microplastics into the environment and, eventually, our food and water. The study found that baking this foam at a moderate temperature (120-140°C) creates the best balance of durability and water resistance, making it a promising, biodegradable swap for plastic packaging. While more testing is needed before it hits store shelves, this research is a step toward packaging that won't stick around in landfills or break down into the tiny plastic particles increasingly found in human bodies.
This bachelor's thesis investigates the fabrication of bio-based packaging foam from cellulose-derived material, specifically examining the influence of drying temperature on its resultant properties. Conventional petroleum-derived packaging foams, including expanded polystyrene (EPS) and polyethylene (PE), contribute substantially to environmental degradation through the accumulation of microplastics in ecosystems and persistently low recycling efficiencies. To mitigate these issues, there is a pressing demand for sustainable substitutes sourced from renewable feedstocks. The study underscores the viability of cellulose-based foams as packaging solutions, owing to their inherent biodegradability and diminished reliance on non-renewable fossil fuels. Emphasis is placed on the drying temperature range (90–160°C) as a key factor in refining the foam's microstructure and functional attributes, with the objective of advancing competitive bio-based alternatives to fossil-fuel-derived foams. Foam samples were produced from cellulose pulp with non-toxic additives. The pulp underwent initial shredding and suspension formation, followed by mechanical aeration to generate the foam, and subsequent oven drying under varied thermal conditions. Material characteristics were assessed via mass loss quantification, climate chamber testing with water uptake experiments, scanning electron microscopy (SEM) for microstructural evaluation, and tensile testing for mechanical performance. Drying temperature exerted a pronounced effect on foam attributes. Elevated regimes (140-160°C) expedited dehydration yet resulted in elevated residual humidity (9.5-11.3%). Water uptake peaked at 140°C (42.8%), indicative of enhanced porosity, whereas it diminished at 160°C (37.7%) due to structural compaction. SEM observations revealed that lower temperatures (90-120°C) maintained an open fibrous matrix (pore dimensions 500-550 µm), in contrast to higher temperatures, which induced fibre coalescence and densification (pore dimensions 120-250 µm), thereby augmenting rigidity while compromising resilience. Tensile assessments demonstrated an escalation in Young's modulus from 4.1 MPa (90°C) to 17.7 MPa (160°C), concomitant with a reduction in elongation from 15.5% to 3.9%, rendering the material increasingly brittle. Findings affirm that drying temperature constitutes a pivotal variable in bio-based foam optimisation. An intermediate range (120-140°C) achieves equilibrium among drying kinetics, hydrophobicity, and mechanical robustness, positioning the material as a viable contender against petroleum-based counterparts. Future investigations are advised to incorporate autoclave systems for precise thermal modulation during in-oven processing. This research accentuates the significance of biodegradable substrates in fostering an eco-conscious packaging sector.