Study of the Flexural Strength of Recycled Dyed Cotton Fiber Reinforced Polypropylene Composites and the Effect of the Use of Maleic Anhydride as Coupling Agent

The flexural strengths of composite materials composed of polypropylene reinforced with cotton fibers recycled from textile waste are presented. Materials with and without coupling agents were prepared. The analysis of the flexural strength of the specimens showed promising properties, both, in the case of the coupled and uncoupled materials, showing their ability to substitute glass fiber reinforced composites. The presence of dyes in the recycled fibers had a noticeable impact on the properties of the composite. A micromechanics analysis showed that the interphase between the matrix and the reinforcements was stronger than expected for uncoupled materials and weaker than expected for coupled ones. The presence of dyes in the fiber surface had a positive effect by decreasing the hydrophilicity of the fibers, and at the same time inhibited the full exploitation of the coupling agents.

Automated summary

The study found that polypropylene composite materials reinforced with recycled cotton fibers showed promising properties in terms of flexural strength, capable of replacing glass fiber reinforced materials. The presence of dyes in the fibers had a significant impact on the properties of the composite, improving performance by reducing fiber hydrophilicity and inhibiting the full utilization of coupling agents.