Liquid Ammonia Treatment Research Articles

Mechanical Properties of Polyester/Cotton and Polyester/Rayon Fabrics Treated with Ammonia-Gas

Liquid ammonia treatment has already been carried out practically to improve the soft hand of the cotton fabric. In a previous paper, we reported that the shearing and bending parameters of polyester/cotton (65/35) fabric treated with liquid ammonia decreased apparently. Ammonia-gas treatment was carried out for various cellulosic fabrics, and it was effective to decrease the shearing and bending properties in relation to the soft hand of the cellulosic fabric, especially for regenerated cellulosic fabrics. In this study, polyester/cotton (65/35) and polyester/rayon (65/35) fabrics were treated with ammonia-gas, and then KES shearing and bending parameters, crease recovery and heart loop softness were measured to evaluate the fabric hand. The shearing and bending moduli G, B, and the hysteresis widths 2HG, 2HG5 and 2HB decreased apparently. Therefore, it seems that the ammonia-gas treatment is effective for an improvement of the soft hand of the polyester/cotton and polyester/rayon blended fabrics as is the same with the liquid ammonia treatment.

Shearing and Bending Properties of Silk Fabrics Treated with Ammonia Gas

Liquid ammonia treatment of the textile fabric has been studied before now in order to improve the softness of cotton fabric with regard to shape stability finish. Furthermore, we are studying now on an application of ammonia-gas treatment to textile finishing instead of liquid ammonia treatment. In this study, two kinds of silk fabrics were treated with ammonia-gas under atmospheric (0.098 MPa) and at pressures of 2, 4, and 6 kgf/cm2 which correspond to 0.196, 0.392 and 0.588 MPa respectively. After the treatment, shearing and bending hysteresis curves were measured with a KES evaluation system , and then shearing and bending modulus G, B, and the hysteresis width 2HG, 2HG5 and 2HB were obtained. Each parameter decreased obviously by the treatment, especially at a pressured condition. Therefore, it is clear that the ammonia-gas treatment is effective to improve the soft hand of the silk fabric.

The Effect of Liquid-ammonia Treatment on the Enzymatic Hydrolysis of Cellulose Fibres

A pretreatment with liquid ammonia causes improved enzymatic hydrolysability of cotton, lyocell, and viscose fibres. This effect is dependent on the method used for the liquid-ammonia removal. Only if the ammonia is rinsed and neutralized with water can the wet fibre be hydrolysed faster by cellulases. Cotton and lyocell lose their high accessibility to enzymes after drying. However, viscose fibres show drastically increased enzymatic hydrolysability after a drying step.

Liquid Ammonia Treatment of Nylon 6 Fabric

Desized and scoured nylon 6 fabric is treated with liquid ammonia (NH3) at -33.4°C. and the effects of the treatment on crystallinity, density, birefringence, DSC thermogram, moisture regain, water absorption, dyeability, and mechanical properties are investigated. The NH3 treatment increases crystallinity and density, but decreases birefringence and water absorption. Although α- and γ-forms coexist in untreated fibers, the γ-form is partially transformed to the α-form by the NH3 treatment, a result that is confirmed by DSC measurements. The NH3 treatment increases crystallinity, dyeing rate, and equilibrium dye uptake, especially with disperse dyes. Mechanical properties of NH3 treated nylon 6 fabric, KES shearing ( G, 2HG, and 2HG5), and bending hysteresis ( B and 2HB) are measured. G, 2HG, 2HG5. B, and 2HB decrease with the treatment. From this result, it is clear that the NH3 treatment improves the hand of nylon 6 fabric.

Hydrocelluloses with low degree of polymerisation from liquid ammonia treated cellulose

The heterogeneous hydrolytic degradation of cellulose after treatment with liquid ammonia has been studied. The level off degree of polymerisation (LODP) of liquid ammonia treated (LAT) linters is reached after 3h when hydrolysed in hydrochloric acid (6.5mol/l) at 60°C. The hydrocelluloses were characterized as trimethylsilyl derivatives and as tricarbanilates. LODPs of non-activated celluloses were in the range from 55 to 77, while LAT celluloses had LODPs between 27 and 39. Trimethylsilyl derivatives and tricarbanilates gave almost identical elution curves in size exclusion chromatography indicating comparable hydrodynamic volumes. Glass transition temperatures of trimethylsilyl celluloses with DPs from 27 to 39 were found to be lower than those of the derivatives of the parent celluloses (Avicel, cotton linters) and showed a dependence on molar mass indicating that oligomeric celluloses are obtained by the method reported. Treatment of cellulose in aqueous ammonia was less efficient than liquid ammonia treatment.

Liquid Ammonia Treatment of Polyester/Cotton Fabric.

Polyester / Cotton (50/50, 65/35) fabrics were treated with liquid ammonia under practical conditions, followed by resin-finishing with nitrogen-contained glyoxal resin NS-19 (Sumitomo Chemical Co.). Nitrogen content, washing shrinkage, crease recovery angle, softness, and KES shearing and bending properties were measured. Nitrogen content of the NH3 treated cotton fabric after resin treatment is obviously decreased as the same behavior in dyeing with CI Direct Blue 1. Although washing shrinkage and crease recovery were diminished with the NH3 treatment, the shrinkage and crease recovery were decreased much more with an increase of polyester fiber content. KES shearing and bending parameters are also decreased with the NH3 treatment.

Liquid Ammonia Treatment of Lyocell.

It is well known that liquid ammonia is effective to improve the hand of cotton fabric and the treatment is carried out practically at present. In this study, we have done liquid ammonia treatment of regenerated cellulosefiber lyocell produced by the solvent spinning with N-methyl morphorine N-oxide. Change of the fiber structure by the treatment was investigated on the basis of the X-ray diffraction, dyeing properties, and KES shearing and bending hystereis characteristics. Cellulose II of the untreated lyocell was partially transformed to Cellulose III I I by the treatment and crystallinity decreased only a little compared with the untreated. Apparent dyeing rate, diffusion coefficent and saturation dye uptake were decreased a little by the treatment, while hand of the fabric was changed a little to stiffer. From these results, the NH 3 treatment of lyocell was not effective for improvement of the hand in comparing with the cotton fabric. Furthermore, polynosic fabric was treated with NH 3 and the effect was investingated with X-ray diffraction and dyeing rate.

Effect of Liquid Ammonia, Sodium Hydroxide/Liquid Ammonia, and Subsequent Cellulase Treatments on Mechanical Properties of Cotton Fabric

Liquid ammonia and cellulase treatments are known to be effective in improving the soft hand of cotton fabrics. In this study, cotton fabric is treated with liquid ammonia, sodium hydroxide/liquid ammonia, and subsequently with cellulase. Shearing and bending hysteresis curves are measured with a KES instrument. Shearing G, bending modulus B, and hysteresis widths 2HG and 2HB are calculated on the basis of the curves. G, B, 2HG, and 2HB decrease with the NH3 treatment, especially with NaOH/NH3. Although inde pendent cellulase treatment decreases the parameters and produces a soft handle, the combination with NH3 , NaOH/NH3 and with susequent cellulase is much more effective at improving hand.

Polysulfide Anions. 1. Structure and Vibrational Spectra of the S22- and S32- Anions. Influence of the Cations on Bond Length and Angle

In a comprehensive study of the M2Sn and M‘Sn alkali (M) and alkaline-earth (M‘) polysulfides, the alkali polysulfides K2S2, Na2S3·NH3, and K2S3 have been prepared by reaction of the metal with sulfur in liquid ammonia and subsequent heat treatments. Their Raman spectra have been analyzed in relation to their known X-ray structures, and that of BaS3 has been revisited. The structure of K2S2 seems intermediate in the M2S2, M‘S2 series since it has two slightly different anions in the unit cell. As for Na2S2, K2S2 has two α and β phases but with a much higher transition temperature ∼310 °C. These results, and those of the literature, allow the S22- bond length to be related to the variation of its electronic structure with the cation electric field. The results obtained for the M2S3 and M‘S3 polysulfides, and those of the literature, show the existence of a low- and a high-temperature phase for K2S3 as for the other M2S3 compounds. The S32- anion geometry, as for S22-, is directly related to the cation electric field. The opening of the SSS angle in BaS3 is linked to the absence of cations at short distance of both terminal sulfur atoms of the S32- anion. It is thus shown that the bond length decreases with the polarizing power of the cations. The force field calculated for these anions are related to the SS bond length. The phase transformations and the stability of these compounds is explained by the polarizing power of the cation, which drives the volume left free for the anion in the crystal.

Effects of Sodium Hydroxide and Liquid Ammonia Treatments On Shape Changes of Cross-Sectional of Cotton Fibers Due to Swelling

Effects of Sodium Hydroxide and Liquid Ammonia Treatments On Shape Changes of Cross-Sectional of Cotton Fibers Due to Swelling

Dyeing properties of cotton fibres treated with liquid ammonia

Both scoured and sodium hydroxide mercerised cotton fibres have been treated with liquid ammonia atndash33.4°C using commercial operating equipment and then the ammonia removed at 130°C in a hot drum. The moisture regain and water absorbency of the fibres treated with liquid ammonia were increased compared with values on untreated fibres, whereas both these parameters on mercerised cotton fibres were decreased by subsequent liquid ammonia treatment. The fibres were dyed with CI Direct Red 2 and CI Direct Blue 1. Liquid ammonia treatment of the scoured cotton fibres increased the rate of dyeing, equilibrium dye adsorption, standard affinity, heat of dyeing and change of entropy, while the dyeing properties of mercerised cotton were adversely affected by subsequent liquid ammonia treatment.

液体アンモニア処理木材の割裂破壊におけるＡＥの挙動

The acoustic emission (AE) signals associated with the cleavage fracture process were measured during fracture toughness tests of Sugi (Cryptomeria japonica) and Red lauan (Shorea negrosensis) woods. In addition, the effects of liquid ammonia treatment on the fracture toughness and the AE parameters such as event count, amplitude distribution and spectrum were examined.The following results were obtained;The AE total count, NT under the tests up to the maximum load in Sugi was larger than that of Red lauan wood. For both woods, NT of radial direction (crack surface: TL plane) was larger than that of tangential direction (RL plane). After the liquid ammonia treatment, AE events were decreased considerably, and NT in Sugi and Red lauan were reduced to one fifth and half, respectively.From the AE amplitude distribution analysis, the difference in distribution profile between RL- and TL-cracking was observed in untreated Sugi, but not observed in treated Sugi, nor in treated and untreated Red lauan.The characteristics of AE spectra in TL and RL planes were examined, but any good result could not be obtained.The fracture toughness, GIC of TL and RL planes in Red lauan were approximately 0.42 and 0.25N/cm, respectively. After treating with liquid ammonia, GIC was increased with the treatment time. The GIC of TL plane had a constant value (1.43N/cm) after 8 hours of the treatment, and the GIC of RL plane took a maximum value (0.97N/cm) at 15 hours.

The Effect of Cross-linking with Dimethyloldihydroxyethyleneurea on the Mechanical Properties of Liquid-ammonia-treated Cotton Fibres

A study is reported of the effect on the mechanical properties of cotton fibres treated with liquid ammonia before application of dimethyloldihydroxyethyleneurea (DMDHEU). The properties are compared with those of the same cotton mercerized and then treated with DMDHEU. It appears from density determinations that the location of the DMDHEU in liquid-ammonia-treated (LAT) samples differs from that in the starting or mercerized counterpart. Liquid-ammonia treatment affects the breaking load and breaking extension of cotton less than mercerization. DMDHEU application decreases the strength and extensibility of LAT cotton and increases its brittleness. Although the trends are similar, there are significant differences in the magnitudes of the effects of mercerization and liquid-ammonia pretreatments on the tensile properties of the fibres. However, the dissimilarities do not appear to be significantly reflected in the brittleness properties. Liquid-ammonia treatment does not seem to improve the fatigue properties of cotton, and application of DMDHEU to LAT cotton causes a reduction in the flex life.

Effects of structural changes on thermal properties and pyrolysis of modified cotton fibres

The changes resulting in the supramolecular structure of cotton fibres after mercerization at different temperatures were investigated by means of X-ray diffraction, sorption measurements and determination of the degree of polymerization. For comparison, corresponding measurements were also carried out after liquid ammonia treatment. Pyrolysis of the mercerized cotton samples showed that the levoglucosan yield of NaOH-treated samples is less than that of untreated or NH3-treated samples. Comparisons were made of the thermal stability of the modified cotton samples, as indicated by DTA and TG.A decrease in the percentage crystallinity was found to lower the onset and peak temperatures of the major decomposition reactions. An NH3-treated sample (acetone) was less thermally stable than untreated or mercerized samples.

Effect of Scouring / Bleaching, Caustic Mercerization, and Liquid Ammonia Treatment on the Pore Structure of Cotton Textile Fibers

The pore structure of cotton was followed through three pretreatments that com monly precede chemical modification for imparting easy care or other functional properties. These treatments included scouring/bleaching, caustic mercerization, and a liquid ammonia treatment with removal by volatilization at elevated temperature. The results include data on the pore structure of the fiber in the greige state. A reverse gel permeation chromatographic technique was used. Columns were prepared from whole cotton fibers in the form of batting, and three series of water soluble solutes were used to study their elution characteristics. The solutes were series of oligomeric sugars, ethylene glycols, and glymes ( ethylene glycol dimethyl ethers) with molecular dimensions in the range of conventional finishing agents for cotton. Scouring/bleaching decreased the water holding capacity of the greige cotton as measured by water of imbibition, but increased it as indicated by gel permeation measurements. The internal volume accessible to water was substantially increased by caustic mercerization, but was only slightly affected by liquid ammonia treatment. The relative accessibility of the cotton fibers to molecules the size of durable press finishing agents was slightly increased by scouring/bleaching, substantially increased by caustic mercerization, but moderately reduced by liquid ammonia treatment. Accessibility to molecules near the permeability limits of the fibers followed similar trends, but differences were greater. Scouring/bleaching increased the permeability limit of the greige fibers, but subsequent mercerization or liquid ammonia treatment decreased it. There was a noteworthy difference in permeability limit and relative accessibility to large molecules. This is accounted for by a decrease in the rate of change in pore size on scouring/bleaching, but substantial increases, to generally more than double, on subsequent caustic mer cerization or liquid ammonia treatment of the scoured / bleached cotton.

Effects of Differential Foam Application of Durable Press and Fluorochemical Finishes to Cotton Fabric

In this study, the effects of differential foam application of durable press (DP) and fluorochemical (FC) finishes to cotton fabrics were investigated. Two different degrees of preparatory finishing of 100% cotton print cloth were evaluated: bleach ing only (BL), and bleaching followed by caustic mercerization and liquid ammonia treatment (BL-CM/AT). The two pretreated fabrics were finished separately by one- and two-sided foam applications at 25% wet pick-up with various levels of FC (0 75, 1.00, and 1.25%) and fixed DMDHEU resin (4.00%) add-on, and at 21% wet pick up with 1.00% FC/3.80% DMDHEU add-on. Performance properties (water and oil repellency, wrinkle recovery, and durable press appearance rating) of foam finished cotton fabrics were examined.

Pore structure of modified cotton and its effects on fiber reactive dyeing properties

Changes in the pore structure and sorption of C.I. Reactive Blue 52 in cotton subjected to various kinds of liquid ammonia treatment were studied. The pore volume, pore surface and pore size distribution were determined by sorption measurements on the cotton fibers using macromolecules of varying sizes. From these measurements, the conclusion can be drawn that transition pores in cottons with a diameter of approximately 20–50 Å are responsible for the dye sorption.

Effects of Mercerization, Submercerization, and Liquid Ammonia on Fiber Morphology of Neps in Cotton Fabric

Cotton print cloth containing both immature fiber neps and process neps composed of torn and ruptured mature fibers was treated with mercerizing and submercerizing strength sodium hydroxide and with liquid ammonia. Scanning electron microscopic examination of mercerized samples showed separation of the nep mass and swelling of individual fibers in both types of neps. Treatment with submercerization strength sodium hydroxide resulted in swelling of surface fibers of the nep but retention of much of the overall fiber compactness. Liquid ammonia appeared to have little effect on the swelling of the individual immature fibers, but did achieve a separation of the compact nep mass. After dyeing with each of ten direct dyes, the mercerized samples showed an average increase in visible coverage of neps of 95%, while the dyed sub- mercerized samples showed an average increase in nep coverage of 86%. After liquid ammonia treatment, significant improvement in nep coverage occurred with five of the ten dyes examined.

Mercerisation and liquid ammonia treatment of cotton

Journal of the Society of Dyers and ColouristsVolume 103, Issue 10 p. 342-349 Mercerisation and liquid ammonia treatment of cotton Peter F Greenwood, Peter F Greenwood International Institute for Cotton, Technical Research Division, Kingston Road, Didsbury, Manchester M20 8RDSearch for more papers by this author Peter F Greenwood, Peter F Greenwood International Institute for Cotton, Technical Research Division, Kingston Road, Didsbury, Manchester M20 8RDSearch for more papers by this author First published: October 1987 https://doi.org/10.1111/j.1478-4408.1987.tb01085.xCitations: 22AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume103, Issue10October 1987Pages 342-349 RelatedInformation

液体アンモニアによる木材構造の変化

木材の液体アンモニア処理に伴う構造変化をX線回折と誘電特性より調べた. 木材細胞間層はリグニンで充填された高次構造を有するため, 液安の木材の構造組織内への浸透が起こりにくく, アンモニア付加による安定なアンモニアセルロースへの結晶転換には加圧下での処理が必要である. 液安で膨潤した木材ではアンモニアとセルロースのメチロール基との間に強い相互作用が確められた. アンモニア離脱に伴いセルロース鎖の再配列により非晶化が起こり. メチロール基の回転配向に基づく運動は容易になった. リグニンは液安膨潤により可塑化され三次元構造が緩むため部分的に極性溶媒に溶解する. 液安処理後に溶媒置換した木材では, 乾燥後の結晶化度や収縮量の変化に大きな差を生じた. 高温で液安処理木材の熱安定性が低下することからも, このリグニン三次元構造の緩みが示唆された.