The valorization of straw waste as a sustainable and eco-friendly resource in polymer
composites is critical for resource recycling and environmental preservation. Therefore,
many research works are being carried out regarding the development of wheat straw-based
polymer composites to identify the reinforcing potential of these sustainable resources.
In this study, three different sizes of wheat straw fibers (60–120 mesh, 35–60 mesh,
and 18–35 mesh) were used, and their different ratios (0, 2.5, 5, 10, and 20% by weight)
were systematically investigated for the physical and mechanical properties of polypropylene-based
sustainable composites. The results indicated that the evaluated composites’ properties
are strongly dependent on the quantity and size of the utilized wheat straw. Therefore,
a preference selection index was applied to rank the developed sustainable polymer
composites to select the best composition. Various properties of the composite materials
were considered as criteria for ranking the alternatives, namely tensile strength
and modulus, flexural stress at conventional deflection and flexural modulus, impact
strength, density, water absorption, material cost, and carbon footprint. The decision-making
analysis suggests the alternative with wheat straw content of 20 wt.% (35–60 mesh
size) dominating the performance by maximizing the beneficial criteria and minimizing
the non-beneficial criteria, making it the most suitable alternative. This study will
significantly help formulation designers to deal with the amount and size issues when
developing polymeric composites.
