Effect of Liquid Ammonia on the Fine Structure of Linen Fabrics

Abstract

It has recently been shown that liquid ammonia treatment (water-based process) is very effective in improving the wrinkle recovery, dimensional stability, and resistance to abrasion of the all-linen fabrics. In this study the changes in the fine structure were characterized by measuring the crystallinity and sorption properties of the linen fabrics. In addition, the effect of liquid ammonia on the surface properties of the linen fibers was investigated. X-ray analysis showed that liquid ammonia treatment did not significantly affect the ratio of crystalline and amorphous regions, but a partial recrystallization occurred in the crystalline part, resulting in mixed cellulose I and III lattices in the linen substrates. Although the moisture regain and iodine sorption capacity of the treated linen substrates increased, water retention values, however, were decreased significantly by the intracrystalline swelling treatment.

Assessing the effect of fibre extraction processes on the strength of flax fibre reinforcement

“…The interchangeable crystalline packing from native or natural Cellulose I to Cellulose III I using ammonia is well documented [18,26]. Liquid ammonia has been applied as an industrial process to improve crease resistance in easy care natural fibre garments [20,27]. The alteration of cellulose intermolecular hydrogen bonding by ammonia may explain the improved flexural strength of the treated flax fibre.…”

Liquid ammonia treatment of (cationic) nanofibrillated cellulose/vermiculite composites

“…Notably the volume of the unit cell of cellulose III is around 30 Å 3 larger than that of cellulose I and the density of cellulose III is lower than that of cellulose I 6, 7. Therefore, the distance between cellulose molecules in cellulose III should be larger and hence the accessibility of reactive sites of cellulose molecules in cellulose III to chemical agents is higher 8, 9. Thus, pre‐treatment of cellulose with liquid ammonia enhances its chemical reactivity 3, 10.…”

“…Moreover, in the textile industry, liquid ammonia treatment has been applied to prevent wrinkling after washing or abrasion of fabrics 8. This is apparently related to the fact that liquid ammonia treatment increases the contact angle of water and therefore the hydrophobicity of fabrics 15.…”

“…Further, ammonia‐treated products reveal enhanced extensibility,17 plasticity and softness 18. Apparently, as the fiber surfaces themselves become smoother8 the fibers feel soft and silky 19…”

Properties of differently printed and easy‐care finished linen fabrics

“…Various finishes developed for linen can compensate for some of these less desirable qualities. A major challenge for the industry is to improve the crease resistance of linen fabrics, particularly when they are used for apparel and household textiles [3][4][5][6][7][8].…”