This paper deals with the durable-press finishing for cotton fabrics using dimethylol ethylene urea (DMEU) condensates having various chain lengths. The results obtained at various concentrations of the crosslinking agents showed that such agents with shorter chain lengths improved dry crease recovery angle whereas wet crease recovery angle was not affected by chain length.A better balance between the dry and wet crease recovery angles was obtained by increasing crosslinking agent content and also by using the crosslinking agents with the shorter chain length.The increase of dry and wet crease resistance caused a decrease in the tensile strength of finished fabrics. A small decrease in tensile strength was observed when crosslinking agents with longer chain length were used. The effects of the chain length of crosslinking agents on the physical properties of durable-press cotton fabrics may be explained as the crosslinking structure formed in the finished cotton fabrics.

The crosslinking structure and physical properties of cotton fabrics treated with dimethylol ethyleneurea (DMEU) condensates having different chain lengths were investigated.It was found that the reaction of the reagent changed at 4% of the concentration. A crosslinking reaction between the reagent and cellulose was the main reaction below 4%, whereas the condensation reaction between the reagents occurred predominantly at the concentration above 4%.The dry crease recovery angle was related to the product of the number of crosslinks and the square root of crosslinking length. The wet crease recovery angle was related to the product of the crosslinking length and the number of crosslinks.Accordingly, when the crosslinking length was shorter, the dry crease recovery angle became larger and the balance between dry and wet crease recovery was improved.It was also found that the tensile strength was directly related to the number of crosslinks: fewer crosslinks and longer crosslinking length increased the retention of tensile strength when nitrogen content of treated fabrics was the same.

No abstract

The relation between the curing condition and the cross-linking structure has been studied for rayon, mercerized cotton and cotton fabrics finished with DMEU resin under various conditions of curing time, temperature and catalysts. From the results obtained, the reactions between DMEU resin and cellulose were discussed.The competitive reactions between condensation reaction of resin itself and cross-linking reaction of the resin with cellulose were elucidated from the quantities of Cell-OCH2-N and N-CH2OCH2-N during DMEU resin finishing. These reactions were affected by temperature, and the type and concentration of the catalysts. In general, higher temperature and higher acidity of catalyst were in favour of the cross-linking reaction between resin and cellulose, and tended to form the cross-links of shorter length. It was also found that the condensation reaction of resin itself was initiated with the formation of N-CH2 OCH2 -N and followed by the decomposition of N-CH2 OCH2 -N into N-CH2-N and free CH2O. The later stage of the reaction was influenced by the curing temperature and the catalyst.Different types of cellulose, such as rayon, cotton and mercerized cotton, showed a similar reaction mechanism, but the rate of reaction and the length of cross-links were varied. It was found that the reaction rate was the highest for rayon, modest for the mercerized cotton, and the lowest for cotton. On the contrary, in terms of the length of cross-links formed, cotton showed the greatest, and the mercerized cotton came next which was followed by rayon.

No abstract