Full-degradable composites reinforced by the low temperature treated cotton fabrics with enhanced strength and interfacial bonding

Abstract

The improper disposal of vast discarded cotton fabrics results in environmental pollution and waste of valuable cellulose resource. Full-degradable composites were hence developed from biodegradable matrices, poly (lactic acid) (PLA) and cellulose acetate (CA), with the reinforcement of the cotton fabrics treated by a low-temperature alkali/urea treatment. This treatment could provide cotton fabrics with a compacter structure, 18.4% enhancement in tensile strength, roughened fiber surface and raised hydrophilicity. After the treatment, the composites displayed 9.7–10.1% enhancement in tensile strengths, 36.3–66.5% rise in tensile moduli, 24.7–39.62% increment in flexural strengths and 42.4–52.1% improvement in flexural moduli. Compared to the PLA composites, the treated cotton fabric/CA composites displayed higher improvements in their properties due to better interfacial bonding between fabrics and the hydrophilic CA matrix, which was proven by a 42.8% increment in peeling strength. The stronger interfacial adhesion also prevented the invasion of microorganism and feculence, and reduced the degradation rate of the CA composites in soil. However, the hydrophilic nature made the CA composites more vulnerable to degradation in water. Considering the low cost, saved resource, less pollution, and acceptable properties for applications, the approach developed in this work possesses the potential to promote an environmentally friendly and sustainable reuse process for discarded cotton fabrics.