Fuente: Polymers Polymers, Vol. 18, Pages 1302: Regenerated Viscose Fibers Enabled by Recycled Cotton Pulps with Different Degrees of Polymerization from Waste Textiles
Polymers doi: 10.3390/polym18111302
Authors:
Huansheng Cai
Lin Chen
Xiuli Wang

High-value recycling of waste cotton-containing fabrics is crucial for the sustainable development of the textile industry. In this study, cotton pulps with different degrees of polymerization (DP = 512–789) from waste polyester/cotton fabrics are systematically evaluated for viscose fiber production. The insolubles in the spinning solution and the effects of DP on its rheological behavior are examined. Based on the mechanical properties of the prepared viscose fibers, the spinning parameters (draw ratio, coagulation bath temperature, and H2SO4 concentration) are optimized. The results show that recycled pulps can produce spinning solutions without insolubles, indicating good spinnability and viscoelastic behavior similar to commercial wood pulp. Higher DP increases apparent viscosity and high-frequency elasticity. Under the optimal spinning conditions (draw ratio 1:1.13, coagulation bath temperature 40 °C, and H2SO4 concentration 8%), the viscose fibers prepared from recycled cotton pulp with DP = 789 achieve a dry tenacity of 2.31 cN/dtex, which is 37.5% higher than that of wood pulp-based viscose fibers, and exhibit higher elongation at break. This study provides a basis for quality control and process improvement in producing high-tenacity viscose fibers from recycled cotton pulp, paving the way for high-value recycling of waste cotton-containing fabrics.