Indian Journal of Fibre & Textile Research

VOL.27

                                    NUMBER 2 

                                       JUNE 2002

 

CONTENTS

Investigations into homogeneity of coir fibres

P K Banerjee, R Chattopadhyay & A Guha

 

111

Influence of some test parameters on friction in acrylic fibres

K R Salhotra, R V M Gowda & S M Ishtiaque

 

117

Twist structure of friction-spun yarns: Part I—Open-end DREF-II yarns

K R Salhotra, R Chattopadhyay, S Dhamija & R C D Kaushik

 

122

Low stress behaviour of jet-spun yarn

A Mukhopadhyay, I C Sharma & Abhishek Saha

 

130

Apron slippage in ring frame: Part II—Factors affecting apron slippage and their effect on yarn quality

A Das, P Yadav & S M Ishtiaque

 

135

Influence of yarn structure, sizing ingredients and type of sizing on properties and performance of sized yarns: Part II—A comparative study of sized yarn performance for ring- and rotor- spun cotton yarns

A K Sengupta, P Pratihar, P D Kimothi, S Vernekar & M M Alamgir Sayeed

 

142

Influence of yarn structure, sizing ingredients and type of sizing on properties and performance of sized yarns : Part III – A study of attrition during weaving for air-jet, ring and rotor yarns on a modern high speed weaving machine

A K Sengupta, P Pratihar, P D Kimothi , S Vernekar & M M Alamgir Sayeed

 

149

Properties of polyester/ wool parent and air-jet textured yarns and their fabrics

V K Kothari & S K Bari

 

156

Improvement in surface-related properties of poly(ethylene terephthalate)/cotton fabrics by glow-discharge treatment

T Öktem, N Seventekin, H Ayhan & E Pişkin

 

161

Crease-resistant finishing of jute fabric using polycarboxylic acids

A Bagchi & S G Saha

166

Weighting of silk by graft copolymerization technique

S R Karmakar, S Mandal, K Das, D Sadhukhan, S Ghosh & R Manna

 

171

Alternative reducing system for dyeing of cotton with sulphur dyes

R B Chavan & Shirishkumar Vhanbatte

 

179

Synthesis of substituted benzyl ethers and their moth proofing activity against wool pest Anthrenus flavipes Le Conte

Chandrashekhar Waman Acharya & Vidhya Joshi

 

184

Thermal studies on cellulose cyclohexenephosphonate in air

J B Dahiya & Sushila

 

189

Short Communication

 

 

Property modification of Antheraea assama silk fibre through graft copolymerization

A M Das, C N Saikia & S Hussain

194 

Review Article

 

 

Solvent-induced modifications in poly(ethylene terephthalate) structure, properties and dyeability

D Chidambaram, R Venkatraj & P Manisankar

199

 


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 111-116

 

Investigations into homogeneity of coir fibres

P K Banerjee, R Chattopadhyay & A Guha

Experimental investigations on certain dimensional and mechanical properties of retted coir fibres reveal a very broad spectrum. The fibres measuring less than 150 mm in length appear very similar in terms of all the properties investigated and hence it is suggested that these fibres should be targeted for segregation and softening in order to design new processes and products ¾ among others the very promising coir-based geotextiles ¾ for coir industry.

          Keywords: Coir fibre, Geotextiles

 

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 117-121

 

Influence of some test parameters on friction in acrylic fibres

K R Salhotra, R V M Gowda & S M Ishtiaque

The influence of operational factors on friction in acrylic fibres of 38 mm and 1.65 dtex has been studied. The increase in normal force decreases the coefficient of friction and results in a more pronounced stick-slip effect. The values for friction indices 'a' and 'n' in the equation F=aNn are found to be 0.71 and 0.90 respectively. The sliding speed has a great influence on the smoothness of fibre movement. The stick-slip effect is more pronounced at slow sliding speeds and progressively reduces at higher speeds with the result that the difference 'ms- md ' becomes smaller. The decrease in the area of contact (fringe width) decreases the coefficient of friction.

Keywords: Acrylic fibre, Coefficient of friction, Frictional force, Sliding speed

 

 

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 122-129

 

Twist structure of friction-spun yarns: Part I – Open-end DREF-II yarns

K R Salhotra , R Chattopadhyay, S Dhamija & R C D Kaushik

 

The twist structure of friction-spun yarns has been explored through the development of an accurate method of twist measurement. It has been found that the optical method, based on the measurement of fibre helix angle and helix diameter through the well-known tracer fibre technique, is the most accurate technique for measuring twist. The twist values obtained by this method have been found to correlate well with those given by other methods of twist testing. Corresponding correlation coefficients and the regression equations have also been derived. The position of the integrating fibres along the length of the fibre assembly zone does not influence the amount of twist inserted in open-end DREF-II yarn. The level of twist is determined by the fibre and process parameters under which the yarn is spun. Twist level drops with the increase in fibre length from 25 mm to 44 mm but shows a slight increase thereafter. The coarser yarns show lower twist than the finer ones. The use of coarser fibres results in lower amount of twist in the yarn while an increase in suction pressure increases it.

Keywords : DREF-II yarns, Friction-spun yarns, Tracer fibre technique, Yarn twist

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 130-134

 

Low stress behaviour of jet-spun yarn

A Mukhopadhyay, I C Sharma & Abhishek Saha

The influence of first nozzle pressure, gauge length, main draft and condenser width on the initial modulus and flexural rigidity of polyester and viscose yarns has been studied using the Box-Behnken experimental design. The interaction effect among the process variables has been analyzed. It is observed that the initial modulus and flexural rigidity of jet-spun yarn increase with the increase in first nozzle pressure, gauge length and condenser width individually when the other variables are set at lower levels. However, the above yarn characteristics may decrease with the change of one variable at a time keeping the other variables at higher levels. The changes in yarn flexural rigidity with the process variables can be predicted from the yarn initial modulus.

Keywords : Air-jet spinning, Flexural rigidity, Initial modulus, Polyester yarn, Viscose yarn, Yarn properties

 

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 135-141

 

Apron slippage in ring frame : Part II ¾ Factors affecting apron slippage and their effect on yarn quality

A Das,  P Yadav & S M Ishtiaque

The effect of various roving and drafting parameters like roving hank, roving TM, top arm pressure, spacer size and break draft on apron slippage has been studied. It is observed that both bottom apron slippage and apron-to-apron slippage change with the change in the above parameters. With the change in these parameters, when the apron slippage increases the yarn quality in general deteriorates and vice versa.

Keywords : Apron slippage, Break draft, Roving TM, Spacer size, Top arm pressure

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 142-148

 

Influence of yarn structure, sizing ingredients and type of sizing on properties and performance of sized yarns : Part II ¾ A comparative study of sized yarn performance for ring- and rotor-spun cotton yarns

A K Sengupta, P Pratihar , P D Kimothi , S Vernekar & M M Alamgir Sayeed

A comparative study on influence of structural differences of ring- and rotor-spun cotton yarns on the process of sizing and the performance of sized yarns against abrasion has been carried out using the 6s and 16s ring and rotor yarns sized with cold and hot brand PVA at different concentrations (9%, 7% and 5%) and drying rates (70°C and 140°C). It is observed that, in general, the abrasion resistance of rotor yarns is better than that of ring yarns. The rotor yarns give better abrasion resistance at 140°C because the higher temperature reduces size migration from inside to surface of the yarn, thereby ensuring more uniform deposition of size along the cross-section of the yarn. A better size distribution reinforces the open structure of rotor yarns and improves cohesion.

Keywords : Cotton, Ring yarn, Rotor yarn, Sizing, Yarn structure

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 149-155

 

Influence of yarn structure, sizing ingredients and type of sizing on properties and performance of sized yarns : Part III – A study of attrition during weaving for air-jet, ring and rotor yarns on a modern high speed weaving machine

A K Sengupta, P Pratihar , P D Kimothi, S Vernekar & M M Alamgir Sayeed 

 

How best the yarns of a given spinning system can be sized with optimum cost to overcome attritive forces acting on warp yarns during weaving has been studied. Polyester/viscose (70:30) yarns (30s) obtained from the three spinning systems, viz. air-jet, ring and rotor, were sized with cold brand PVA and tested for abrasion and tensile properties. Using these yarns in warp, a plain weave fabric was woven on a Dornier Rapier loom. The yarns were then unravelled from the fabric and tested for the abrasion and tensile properties. It is observed that among the ring, rotor and air-jet yarns, the excellent abrasion resistance is obtained with air-jet yarn at higher size concentration and slow rate of drying. This is because at higher concentration there is good size film formation on the yarn surface and at slow rate of drying more outward size migration takes place, resulting in better size encapsulation. An air-jet yarn whose strength properties are derived from the tightness and compression of the surface wrappings is, therefore, protected from the abrasion forces, caused during weaving, by this size film for a longer duration.

Keywords : Air-jet yarn, Ring yarn, Rotor yarn, Sizing, Weaving

 

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 156-160

 

Properties of polyester/wool parent and air‑jet textured yarns and their fabrics

V K Kothari & S K Bari

Air‑jet texturing of polyester/wool blended spun yarn has been carried out and woven and knitted fabrics have been produced using parent and textured yarns. The properties of parent and textured yarns and of the fabrics produced using parent and textured yarns have been compared. It is observed that the yarn bulk increases while the tensile and evenness properties become inferior on air‑jet texturing. The textured yarn fabrics have lower air permeability, higher thermal resistance, higher abrasion resistance and inferior strength-related properties as compared to the parent yarn fabrics. Air‑jet textured polyester/wool blend spun yarns can be used where higher comfort-related properties are desirable.

Keywords : Air-jet texturing, Fabric properties, Polyester/wool blended yarn, Textured yarn

 

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 161-165

 

Improvement in surface-related properties of poly(ethylene terephthalate)/cotton fabrics by glow-discharge treatment

T Öktem,  N Seventekin, H Ayhan & E Pişkin

 

Poly(ethylene terephthalate)/cotton fabrics have been treated in low-temperature plasmas to increase the hydrophilicity and, therefore, to impart soil resistance and to improve dyeability. The fabrics have been treated in glow-discharge apparatus using acrylic acid and water plasmas. Two alternative modifications were applied. The plasma conditions, such as exposure time and discharge power, were varied to control the extent of plasma surface modification in the first approach, while the acrylic acid content and the incubation time were changed in the second approach. It is observed that the glow-discharge treatment significantly improves the wettability of the fabrics. More hydrophilic surfaces are created due to the treatment and, therefore, the dyeability of the fabrics is much better. No significant colour change, neither with repeated washing cycles nor with long period of storage, is observed.

Keywords: Dyeability, Glow-discharge treatment, PET/cotton fabric, Soil resistance, Wettability

 

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 166-170

 

Crease-resistant finishing of jute fabric using polycarboxylic acids

A Bagchi  & S G Saha

The potentialities of jute fabric to develop wrinkle resistance through crosslinking with polycarboxylic acids, like citric acid and 1,2,3,4-butane tetracarboxylic acid (B T C A), as an alternative to the conventional N-methylol compounds have been studied in the presence of phosphate catalyst by pad-dry-cure technique. It is observed that for jute fabrics, B T C A shows better crease recovery than citric acid at all the concentrations studied. Citric acid finishing may, however, be used in the applications that do not require high crease recovery as it is less expensive. FTIR spectroscopy reveals the formation of ester crosslinks between jute fibre and polycarboxylic acid.

           Keywords   Butane tetracarboxylic acid, Citric acid, Crease recovery angle, Jute

 

 

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 171-178

 

Weighting of silk by graft copolymerization technique

S R Karmakar, S Mandal, K Das, D Sadhukhan, S Ghosh & R Manna

 

Wild silk yarns and fabrics have been graft copolymerized with two monomers, namely methyl methacrylate (MMA) and methacrylic acid (MAA), using potassium peroxidisulphate and cerric ammonium sulphate to minimize homopolymer formation. The optimum conditions of grafting have been standardized. The changes in the dyeing behaviour using acid, basic and reactive dyes have also been investigated to understand whether the grafting should be carried out before, after and during dyeing operation. It is observed that the graft copolymerization with MAA and MMA affects the dyeability of silk. The effect on various physical properties of silk fibres grafted before and after dyeing is quite noteworthy. The higher the graft add-on the more is the variation in physical properties. The dyeing followed by grafting using reactive dyes shows favoured properties and is recommended for weighting of silk on industrial scale.

Keywords : Breaking load, Degumming, Drape coefficient, Dyeing, Grafting, Weighting

 

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 179-183

 

Alternative reducing system for dyeing of cotton with sulphur dyes

R B Chavan  & Shirishkumar Vhanbatte

An attempt has been made to replace sodium sulphide by reducing sugar, obtained by acid hydrolysis of molasses, in dyeing of cotton with sulphur dyes. The results of dyeing using reducing sugar in alkaline condition have been compared with those of the conventional dyeing with sodium sulphide. It is observed that the depth of shade, expressed as K/S value, is deeper in case of dyeing with reducing sugar than in conventional dyeing.

Keywords:      Cotton, Dyeing, Molasses, Reducing sugar, Sulphur dye

 

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 184-188

 

Synthesis of substituted benzyl ethers and their moth proofing activity
against wool pest Anthrenus flavipes Le Conte

Chandrashekhar Waman Acharya & Vidya Joshi

 

Substituted benzyl phenylethyl ethers (IIIa-d) and dibenzyl ethers (IIIe-h) have been synthesized and evaluated for moth proofing activity against the larvae of Anthrenus flavipes Le Conte on woollen fabric. It is observed that the benzyl phenylethyl ether (IIIa) is effective at the treatment level of 0.5% on the fabric weight. The incorporation of substituent containing -NO2 group in IIIa and dibenzyl ether (IIIe) reduces the moth proofing activity to a considerable extent.

Keywords: Anthrenus flavipes Le Conte, Benzyl phenylethyl ether, Dibenzyl ether, Moth proofing, Wool

 

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 189-193

 

Thermal studies on cellulose cyclohexenephosphonate in air

J B Dahiya  & Sushila

The flame retardancy of the cellulose cyclohexenephosphonate (CCHP) has been investigated by the kinetics of thermal degradation using differential thermal analysis (DTA) and thermogravimetry (TG) from ambient temperature to 700°C in dynamic air. Various parameters such as energy, entropy and free energy of activation have been calculated using the Broido method and transition state theory. For the decomposition stage of thermal degradation, the activation energy of CCHP has been found to be 133.83 kJ mol-1 which is lower than that of cellulose (187.0 kJ mol-1). Higher char yield of CCHP as compared to cellulose leads to the conclusion that CCHP is a good flame retardant. The IR spectra of the chars of modified cellulose indicate formation of compounds containing C=O, C=C and P=O groups. The mechanism of thermal degradation of CCHP has been proposed.

Keywords: Cellulose, Cellulose cyclohexenephosphonate, Flame retardant, Thermal degradation

 

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 194-198

 

Property modification of  Antheraea assama silk fibre through graft copolymerization

A M Das  C N Saikia  & S Hussain

Graft copolymerization of methylmethacrylate and acrylamide onto Antheraea assama silk fibre was carried out in aqueous medium using CeIV initiator system. The extent of grafting was evaluated as a function of reaction time and temperature. The grafted products were characterized by infrared spectroscopy. Their thermal behaviour was studied by TG and DTG techniques in static air at  20°C min-1 in the range 30-800°C and the surface characteristics were studied with the help of scanning electron microscopy. The grafted fibres exhibited absence of water staining with decrease in water retention values and increase in tensile strength.

Keywords : Acrylamide, Graft copolymerization, Methylmeth-acrylate, Non-mulberry silk, Vinyl monomer, Water retention value, Water staining

 

Indian Journal of Fibre & Textile Research

Vol. 27, June 2002, pp. 199-210

 

Solvent-induced modifications in poly (ethylene terephthalate)
structure, properties and dyeability

D Chidambaram ,, R Venkatraj  & P Manisankar

Poly (ethylene terephthalate) fibre (PET) is the commonly used man-made fibre for majority of end-use applications. In the past few decades, the significant technological developments have taken place pertaining to the production processes of PET. Regarding the dyeing of PET, there is a constant upsurge in research and development activities to modify the structure of PET with a view to develop energy efficient processes. Among the notable developments, the low molecular weight solvent treatment results in physical modifications of polymer and fibre like PET, which include structural modifications and changes in properties. Owing to the structural modifications of PET fibre, the dyeability also improves. Some of the pioneering works on solvent-induced modifications of PET structure, properties and dyeability during the past few years have been reviewed.

Keywords: Poly(ethylene terephthalate), Structural modification, Mechanical properties, Dyeability