Pore Structure of Cotton Fabrics Crosslinked with Formaldehyde-Free Reagents

Abstract

Pore structures of cotton fabric crosslinked with several formaldehyde-free durable press reagents are elucidated, and results are compared with those for the industry standard, DMDHEU (dimethyloldihydroxyethyleneurea). The formaldehyde-free reagents were BTCA (butanetetracarboxylic acid), DHDMI (dihydroxydimethylimidazolidinone), and the glyoxal/glycol system; the fabric was an 80 × 80 cotton print-cloth. Treatments were designed to impart the same degree of conditioned wrinkle recovery (WRA) to the fabric. A reverse gel permeation chromatographic technique was used to follow changes in pore size distribution. Columns were prepared by settling water slurries of the ground cotton in a conventional manner. Two series of water soluble solutes, which were series of oligomeric sugars and ethylene glycols, were used to study the elution characteristics of the unmodified and crosslinked samples. Internal structure differences were also elucidated by means of moisture regain, considered to be a measure of the internal surface of the cotton fiber in the conditioned state, and water of imbibition, a measure of internal volume in the water-swollen state. Formaldehyde-free crosslinking reagents effect a lower level of collapse of the internal pore structure of the cotton fiber than does DMDHEU at generally comparable levels of resilience.

Ink‐jet printing process for lyocell and cotton fibres. Part 2: The relationship of colour strength and dye fixation to ink penetration

“…Crosslinking in cellulosic fibres commonly reduces dye uptake by reducing accessibility of the dye through restricting the movement of the cellulose chains in the non-crystalline regions of the fibres. Three features of crosslinking on cellulosic fibres have been highlighted [18][19][20] in determining properties: primary valence bonds -the covalent bonds formed between the crosslinking agent and the cellulose chains; secondary valence bonds -hydrogen bonding, which are capable of disruption by water and certain swelling agents and of reformation on drying; and the location of the bonds. In contrast, Tencel A100, on which the crosslinking treatment is applied in its wet state, is reported to have an open fibre structure, which leads to higher water retention than standard Tencel, increasing dye accessibility and allowing higher dye uptake and thus higher fixation during reactive dyeing [15,16].…”

Esterification of wood with citric acid: The catalytic effects of sodium hypophosphite (SHP)

“…Apparently the two adjacent carboxylic acid groups dehydrate and form a five-membered cyclic anhydride intermediate, which may further react with a hydroxyl group of cellulose via esterification (Bertoniere and King 1992;Wing 1997;Yang and Wang 2000). Accordingly the maximum number of ester bonds is one less than the total number of carboxylic groups in the reactant (Bertoniere and King 1992).…”

Crosslinking of cotton cellulose in the presence of serine and glycine. II. Pore structures and agent distribution

“…Those phenomena strongly suggested that the pore structure caused by the crosslinking of DMDHEU–α‐amino acid might be different from that for DMDHEU alone. Many other authors5–8 mentioned that the pore structures of the treated fabrics are affected by varying the functional groups of crosslinking agents. We are interested in the effect of the coreactants of the α‐amino acids having one carboxylic acid group and one amine group on the pore structure of the treated fabrics, which has never been reported.…”

“…The SEM pictures will also be used to confirm the state of the pore structures of DMDHEU and DMDHEU–α‐amino acids‐treated fibers. On the other hand, a negative staining method described by Rowland et al8, 13, 14 will be used to determine the distribution of agents on the treated fabrics.…”