Investigation into the Effects of an Easy Care Cross-linking Agent on the Properties of the Pulp Reclaimed from Cotton Based Waste Garments

Aims: To investigate the potential pulp reclamation from easy care treated cotton waste garments for potential paper making and regeneration of fibres.

Study Design: This is an experimental laboratory research project.

Place and Duration of Study: School of Materials, University of Manchester, between October 2009 and March 2013.

Methodology: Cotton fabric was treated with Dimethylol dihydroxyethylene urea (DMDHEU) at 60, 100 and 140 g/L concentration levels. The fabrics were then shredded and pulped on laboratory Valley beater. Part of the resultant pulp was formed into hand sheets using the sheet making apparatus. The remaining pulp was analyzed for the wetness test, fines content and fibre length analysis. Tensile strength and Tear strength of the hand sheets were analyzed using Instron tester and Elmendorf machines, respectively. The Kawabata Evaluation System for Fabrics was used to assess the hand properties of the hand sheets. X-ray photoelectron spectroscopy technique was used for the surface chemical analysis of the hand sheets.

Results: It was observed that as the concentration of DMDHEU reacted to cellulose polymer increased, shorter fibres were produced. The DMDHEU free pulp has a mean fibre length of 2.5±0.04 mm whereas after increasing the DMDHEU concentration equivalent to 1.6% surface nitrogen the mean fibre length dropped to 1.2±0.05 mm. Application of the DMDHEU easy care finish on the cotton fabric reduced the tensile strength of the hand sheets from 2.08 kN/m to 0.1 kN/m whereas the tear strength and tensile index were reduced from 1.4 kN to 0.5 kN and 0.9 KNm/g to 0.4 kNm/g, respectively.

Conclusions: The DMDHEU easy care finish produced pulp with shorter fibres, high fines content but hand sheets with relatively weaker mechanical properties. This implies that in order to recover fibres from the cotton waste garments for either fibre regeneration or paper processing the DMDHEU easy care finish must be removed prior to forming of hand sheets.