A Glimpse of Non-Wood Eco-Friendly Packaging
Abstract
As global demand for sustainable packaging grows, the paper industry faces the challenge of finding biodegradable alternative materials. This review examines the feasibility of using non-wood agricultural waste like pineapple leaves, banana fibers, and rice straw as packaging raw materials. Research indicates these fibers are highly promising wood substitutes due to their high cellulose and low lignin content. Fiber blending can significantly enhance the properties of low-grade pulp, while natural biopolymers as additives can further boost the physical and surface properties of the packaging material, providing a viable path for developing eco-friendly and high-performance molded pulp packaging.
1. The Potential of Non-Wood Fibers as Sustainable Packaging Raw Materials
The massive global demand for packaging materials results in significant waste, increasing the burden on landfills. Paper-based molded products are gaining attention as a biodegradable packaging solution. Finding wood substitutes is now a critical task, and agricultural waste is considered an ideal resource, serving as both an economical fiber source and a solution for waste management.
For instance, pineapple leaf fiber is a potential papermaking resource, especially in regions like Mauritius where the leaves are typically discarded as waste. Banana pseudo-stems have been shown to have potential for producing wrapping paper. Cereal straw, in turn, can be used to produce paper-based molded packaging materials, replacing non-biodegradable expanded polystyrene.
2. Performance of Single Non-Wood Fibers in Packaging Applications
Researchers have tested the physical and mechanical properties of paper made from single non-wood fibers for packaging applications. 100% pineapple leaf fiber paper exhibits the highest tensile index and burst index, and has the best absorbency.
However, not all single fibers perform equally well. Some research indicates that paper made from banana stem fibers is substandard, as its fibers are shorter and its structure is weaker. In contrast, pineapple and rice straw fibers show excellent performance and are highly suitable for molded pulp packaging. Other studies also show that 100% banana fiber paper has a high tensile and burst index and demonstrates the highest abrasion resistance, making it a suitable raw material for wrapping paper.
3. Fiber Blending and Packaging Performance Optimization
To overcome the limitations of single fibers and optimize product performance, fiber blending is a common strategy. This not only enhances the strength of packaging materials but also efficiently utilizes different waste resources.
One study blended pineapple leaf fibers with bagasse and wastepaper. Results showed that a 40:60 pineapple-to-bagasse blend provided the best abrasion resistance, while an 80:20 wastepaper-to-pineapple blend had the best crease resistance. This indicates that adjusting the blending ratio can optimize performance for specific packaging applications.
Further research on blending agricultural waste found that mixing substandard banana stem pulp with superior pineapple or rice straw pulp significantly improved tensile strength and Young's modulus (by 63-167% and 55-117%, respectively). Incorporating just 30% of the superior pulp was enough to bring the performance to an acceptable range.
Additionally, when banana fibers were mixed with bagasse and wastepaper to produce wrapping paper, a 20% wastepaper blend resulted in the highest tensile and burst indices, while a 20% bagasse blend showed the best abrasion resistance.
4. Utilizing Biopolymers to Enhance Packaging Material Performance
Beyond blending, additives are also key to improving packaging material performance. Some studies note that the short length of agricultural residue fibers often leads to insufficient strength. Biodegradable biopolymers are gaining attention due to their eco-friendly properties.
A study compared the effects of cationic starch and chitosan as additives, finding that a dose of 0.5 kg/t of chitosan was more promising than 5 kg/t of cationic starch. In a blend of 85% agricultural pulp and 15% hardwood pulp, adding chitosan and applying an oxidized starch surface size significantly improved properties like tear index (2.7%), stiffness (6.5%), and double fold endurance (170%). These results demonstrate that biopolymers can enhance paper properties in a cleaner, more eco-friendly way, making the material better suited for packaging.
5. Conclusion
In summary, non-wood fibers have immense potential as packaging raw materials. They not only help relieve pressure on forests but also effectively utilize agricultural waste.While single non-wood fibers can be used to produce high-performance packaging paper, blending can significantly improve the properties of lower-quality fibers.
Furthermore, using biodegradable biopolymers as additives is an efficient and eco-friendly way to enhance performance. Future research can continue to explore more fiber combinations and cleaner pulping and additive technologies to advance the molded pulp packaging industry toward a more sustainable future.
Reference
[1] Sibaly S, Jeetah P. Production of paper from pineapple leaves[J]. Journal of environmental chemical engineering, 2017, 5(6): 5978-5986.
[2] Rattanawongkun P, Kerddonfag N, Tawichai N, et al. Improving agricultural waste pulps via self-blending concept with potential use in moulded pulp packaging[J]. Journal of Environmental Chemical Engineering, 2020, 8(5): 104320.
[3] Bhardwaj S, Bhardwaj N K, Negi Y S. Cleaner approach for improving the papermaking from agro and hardwood blended pulps using biopolymers[J]. Journal of Cleaner Production, 2019, 213: 134-142.
[4] Curling S F, Laflin N, Davies G M, et al. Feasibility of using straw in a strong, thin, pulp moulded packaging material[J]. Industrial Crops and Products, 2017, 97: 395-400.
[5] Ramdhonee A, Jeetah P. Production of wrapping paper from banana fibres[J]. Journal of environmental chemical engineering, 2017, 5(5): 4298-4306.
