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Indian Journal of Textile ResearchVol. 14. December 1989, Pp, 164-168

Dimensional characteristics of jute and jute-rayon blended fabricscrosslinked with DMDHEU

r-N'C~~m &tA KtMukherjee

Applied Chemistry Division, Indian Jute Industries' Research Association, Calcutta 700 OXS;~"~ ,

Received 24 July 1989; accepted 4 September 1989

Jute and jute-rayon blended fabrics were crosslinked with 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) using metal salt catalysts [MgClz, ZnClz and Zn(NOJ}21, acid catalysts (HCl andCH3COOH) and mixed catalysts (MgCl/HCl and MgCl/CHJCOOH) by the usual pad-dry-curemethod and their dimensional characteristics assessed. The crosslinking treatment reduced the %area shrinkage, i.e. improved the dimensional stability of jute and jute-rayon blended fabrics signifi-cantly. The improved dimensional behaviour of treated fabrics has been attributed to the reductionin the elastic property of amorphous regions of cellulose structure. Crosslinking makes such regionsbehave like orderly oriented regions.

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; '.j Keywords: Crosslinking, Dif!1_ensional characteristics, Jute, Jute-rayon blended fabric, Dimethyloldi-hydroxyethylene ure'a" ' . .

I IntroductionThe dimensional stability, i.e. resistance to

shrinkage or extension on washing, has alwaysbeen considered important for textile fabrics. Ithas become much critical in recent years with theincreasing demand for dimensionally stable fa-brics for dress materials, furnishings, upholsteries,etc. Cellulose fabrics such as cotton and rayonundergo considerable shrinkage after washing.Shrinkage or extension depends upon many fac-tors such as the structure of fibre, construction offabric, distortions and tension imposed on the fa-bric during manufacture and wet processing. Thechanges in dimensional stability can be reducedby fixing the dimension of the fabric in a compre-hensive shrinkage machine where the fabric iscompacted in a mechanical device, a popular pro-cess known as "Sanforizing". In chemical fixation,the cellulose chains of the fabric are crosslinkedwith suitable reagents to improve the dimensionalstability 1.2. It has been observed that jute fabricsshrink approximately 5-12% in width and 4-15%in length. The differential shrinkage in warp andweft directions of jute fabric is perhaps causeddue to the rather high warp-wise tensions towhich the fabrics are subjected during wet pro-cessing, whereas the dimensional behaviour ofgrey fabric shows uniform shrinkage in L,:t1-j warpand weft directions (Table 1). In view of our earli-er srudies':" showing improved wrinkle recovery

164

properties of jute fabrics modified by crosslinkingwith few resins in presence of catalyst, it was con-sidered worthwhile to study the dimensional behav-iour of jute and jute-rayon blended fabrics after cross-linking them with DMDHEU in presence of differenttypes of catalyst. Hence, the present study.

2 Materials and Methods2.1 Materials2.1.1 Fabrics

Grey jute fabric (plain weave, 228 g/rrr',48 x 48 ends and picks/dm), bleached jute fabric(plain weave, 325 g/m-, 60 x 48 ends and picks/drn), and bleached jute-rayon (60:40) blended fa-bric (plain weave, 325 g/rn", 68 x 72 ends andpicks/dm) were used.

Bleached fabrics were prepared as follows. Thefabric was cleaned by scouring with 2% sodiumcarbonate (owf) at 80°C for 30 min. It was thenbleached in a laboratory jigger with alkaline hy-drogen peroxide. This was followed by washingwith water and neutralization with acetic acid togive fabric pH of 6-6.5.

2.1.2 ChemicalsAhuramine YX, an aqueous product containing

51 '1<) solid 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) was used as the erosslinkingagent.

Magnesium chloride. zinc chloride. zinc nitrate. rI

SOM & MUKHERJEE: CHARACTERISTICS OF JUTE AND JUTE-RAYON FABRICS

Table I - Shrinkage behaviour of grey and bleached jute fabrics

SI Fabric specifications % Shrinkage afterN".

3rd wash 4th wash 5th wash1st wash 2nd wash

Warp Weft Warp Weft Warp Weft Warp Weft Warp Weftway way way way way way way way way way

GreyR.2 R.5 8.5 8.8 9.0 R.8 9.0 R.8Ends x picks/drn. 4R x 48 7.4 R.)

Plain weave228 g/rrr'

2 Bleached8.0 7.3 8.5 7.3 8.5Ends x picks/drn, 60 x 48 6.0 7.0 6.5 7.5 7.2

Plain weave325 g/m-

acetic acid and hydrochloric acid (analyticalgrade) were used as catalysts.

2.2 Methods2.2.1 Measurement of Length-wise and Width-wise

ShrinkageThe dimensional changes, i.e. shrinkage or ex-

tension on washing, of the following samples werestudied.1 (a) Jute fabric crosslinked with 2% DMDHEU

and 0.5% MgCI2, cured at 150°C for 5min, washed and dried.

(b) Same as l(a) but crosslinked with 4%DMDHEU and 1% MgCI2•

(c) Same as l(a) but crosslinked with 6%DMDHEU and 1.5% MgCI2•

(d) Same as l(a) but crosslinked with 8%DMDHEU and 2% MgCI2.

(e) Same as l(a) but crosslinked with 10%DMDHEU and 2.5% MgCI2•

(f) Same as l(a) but crosslinked with 12%DMDHEU and 3% MgCl2•

2 Jute-rayon (60:40) fabric samples cross-linked as per samples l(a)-(f).

3 (a) Jute fabric crosslinked with 6% DMDHEUand 2.4% ZnCl2 catalyst, cured at 150°Cfor 5 min, washed and dried.

(b) Same as 3(a) using 2.4% zinc nitrate catal-yst.

(c) Jute fabric crosslinked with 6% DMDHEUand acetic acid catalyst (pH of the bath ad-justed to 2.5), cured at 150°C for 5 min,washed and dried.

(d) Jute fabric crosslinked with 6% DMDHEUand hydrochloric acid catalyst (pH of thebath adjusted to 2.5), cured at 150°C for 5min, washed and dried.

(e) Jute fabric crosslinked with 6% DMDHEUand mixed catalyst containing 1% magne-

sium chloride and acetic acid (pH of thebath adjusted to 2.5), cured at 150°C for 5min, washed and dried.

(f) Jute fabric crosslinked with 6% DMDHEUand mixed catalyst containing 1% magne-sium chloride and hydrochloric acid (pH ofthe bath adjusted to 2.5), cured at 150°Cfor 5 min, washed and dried.

4 Jute-rayon (60:40) fabric samples cross-linked as per samples 3(a)-(f).

The fabric samples l(a)-(f) and 2(a)-(f) weretested for the % area shrinkage.

The fabric samples of 60 em x 60 em we.restitched in all four edges to avoid slippage or dIS-tortion of the fabric during tests. Samples weremarked 45 em distance apart in both warp andweft directions. Five markings were made in boththe directions so that almost entire area of the fa-bric samples was covered. All markings weremade at least 2.5 cm away from the edges of thetest specimen. The samples were was~ed in awash wheel having false bottom contamer andforward and reverse rotation using 5 g/l neutralsoap (material-to-liquir ratio, 1:100) at ~O°C for30 min. After washing, the soap solution wasdrained out and the samples were rinsed twicewith water (each time for 10 min) at room tem-perature. The samples were then taken out, ~y-droextracted, dried in a flat bed pressed dner(AMERESCO), and conditioned at 67% RH and25°C. The shrinkage after the first and subsequentwashes and drying cycle was calculated as follows:

Original length - Final length0;' Length-wise shrinkage = _. .. x 100

o Original length

Original width - Final width x 100% Width-wise shrinkage

Original width

InS

INDIAN J. TEXT. RES., VOL 14, DECEMBER 14X4

The average values of 3 tests are reported inthe results.

2.2.2 Measurement or" Area ShrinkageThe fabric samples of 60 ern x 60 ern were used

for % area shrinkage measurement. An area of 30em x 30 ern was marked on the fabric samplesand then the samples were washed in a washwheel as reported in 2.2.1. The % area shrinkagein each sample was calculated as follows:

Original area - Changed area% Area shrinkage = x 100

Original area

The average values of 3 tests are reported ill

the results.

3 Results and DiscussionJute and jute-rayon (60:40) fabrics crosslinked

with a range of DMDHEU add-on using magne-sium chloride as catalyst were assessed for theirdimensional stability after each and successivefive washings. Fig. 1 shows the effect of concen-tration of crosslinking agerit on shrinkage of juteand jute-rayon (60:40) fabrics. For all the con-centrations, the degree of stabilization in both thewarp and weft directions was found to be veryhigh. 6-8% DMDHEU add-on was found to beadequate since further increase in DMDHEU didnot contribute significantly to further shrinkagecontrol. In the case of jute-rayon blended fabric,the degree of stabilization was marginally lower atequivalent treatment than that of 100% jute fabricand good shrinkage control was obtained at 8%DMDHEU conc. The rayon fibre swells andshrinks considerably more than the jute fibre andaccordingly in blended fabric the resultant shrin-kage is higher than that in jute fabric. For thisreason, a higher amount of crosslinking is re-quired to dimensionally set the jute-rayon fabric.

• Warp wayo Weft way

c.:.'8

7

• v.orp wayo Wczft way

1o (a)

\\\

\

\

\

~\\\

0,,"'0....~

(b) ~-

4 6 8 10 12 2 4 6 B 10 12DMDHEU ADD-ON. -t;

2

Fig. 1 - Relationship between DMDHEU add-on and shrin-kage [(a) 100% jute fabric, and (b) jute-rayon (60:40) blended

fabric]

1M

The effect of DMDHEU cone. on shrinkage ofjute and jute-rayon fabrics on successive washingsis shown in Figs 2 and 3 respectively. It is ob-served from these figures that in the fabrics cross-linked with more than 4% DMDHEU, the shrin-kage practically ceased after second wash and thefabrics approached to stable dimensions.

The effects of crosslinking 6% DMDHEU withjute and 8% DMDHEU with jute-rayon blendedfabrics using different types of catalysts on dimen-sional stability are shown in Table 2. It is ob-served from the table that with all the catalysts,the degree of stabilization of dimension in bothtypes of fabrics is very good, particularly in warpdirection. However, the shrinkage in weft direc-tion is higher than that in warp direction and itbecomes stable in successive washes, i.e. in subse-

9\MJrp way .>:8

7 .r:~6~Cl'o 5 .r:':.x:c.~ 4.J;;

~<.fl3 .....-- • • •2 a- • • • •

~" )( \( \( l(

02 3 4 5 2 3 4 5

No. of Wash

Fig. 2 - Effect of DMDHEU cone. on shrinkage of 100% jutefabric on successive washing [DMDHEU cone: (e) nil, (A)

2%, (I) 4%, ("') 6%, (x) 8%, (0) 10%, and (0) 12%]

10we~

Wlrp way9

8 .r::7

;!

-6~t» A~ 5 ~ • •c-;: 4.J;; • • I • y"A • • •<.fl •3

~2

~0

2 3 4 5 2 3 4 5

No. of Wash

Fig. 3 - Effect of DMDHEU cone, on shrinkage of jute-rayon(60:40) blended fabric on successive washing [DMDHEUcone: (I) nil, (A) 2%, (I) 4%, (c ) 6%, (x) 8%, (0) 10%.

anJ (0) 12%]

SOM & MUKHERJEE: CHARACTERISTICS OF JUTE AND JUTE-RAYON FABRICS

Table 2 - Effect of crosslinking treatment with DMDHEUa using various types of catalyst on shrinkage property of 100% jutefabric" and jute-rayon (60:40) blended fabric"

Catalyst conc. (w/v) % Shrinkage after

1st wash

Jute Jute-rayon

2nd wash 3rdwash

Jute Jute-rayon Jute-rayonJute

Warp Weft Warp Weft Warp Weft Warp Weft Warp Weft Warp Weftway way way way way way way way way way way way

ZnCI2 (2.4%) 0 0.78 0.80 1.17 0.40 0.82 0.85 1.20 0.40 0.85 0.90 1.92

Zn(N03)2 (2.4%) 1.2 1.04 1.56 1.25 1.03 1.05 1.06 1.03 1.03 1.05 1.06 1.03

Acetic acid (pH 2.5) 0.9 1.03 1.06 1.07 1.02 1.04 1.06 1.75 1.02 1.04 1.06 1.08

Hydrochloric acid (pH 2.5) 0.4 0.85 0.76 1.17 0.05 0.09 0.80 1.02 0.015 0.09 1.00 1.02

MgCI2 (1%) + acetic acid (pH 2.5) 1.1 1.02 1.02 1.05 1.02 1.25 l.35 1.70 1.25 1.40 1.05 1.75

MgClz (1%) + hydrochloric acid 0.8 1.03 1.00 1.04 1.00 1.05 1.03 1.05 1.00 1.06 1.05 1.05

aDMDHEU conc.: 6% for jute fabric and 8% for jute-rayon fabric.bWeight, 325 g/m"; ends x picks/dm, 60 x 48."Weight, 325 g/rn"; ends x picks/dm, 60 x 72. •

quent washes the shrinkage value decreases grad-ually.

The shrinkage causes loss in fabric area since itoccurs in both the directions. This is also knownas area shrinkage. The shrinkage in warp direc-tion is not equivalent to that in weft direction andthe relationship between these two are not co-related. The effect of different concentrations ofDMDHEU on % area shrinkage was calculatedon the basis of the change in area (30 em x 30cm) after successive washings. The results areshown in Figs 4a-4c which indicate that the %area shrinkage decreases gradually with the in-crease in DMDHEU concentration.

The change in area or dimensions of warp andweft of a textile woven material on wetting de-pends upon several factors which include (i) typeof fibre, (ii) fabric geometry and (ill) the stress/strain applied to the fabric during mechanical andchemical processing. The principal cause of shrin-kage of a fabric is the swelling of yarns in wateror soap-water solution. The amount of swelling,i.e. increase in yam diameter, is expected to beexactly proportional to the diametrical swelling offibres in yam. Since the shrinkage in jute yam isnegligible (less than 1%), the fabric shrinkagemust come from the structural changes within thefabric. When the fabric is wet and the yam swells,a greater length of warp yam will be required tointerweave the increased diameter of the swollenthreads if the threads are to remain in the sameposition. Since in any of the existing woven struc-tures such extra warp yams are not available, itfollows that contraction in warp direction occurs,resulting in length-wise shrinkage. The shrinkage

20 "') • .Ma labric (b) Jut. IaIric1S 0 Nta-ro)'OflIalrlc

15 ~

DMDt£U02... A 4'".~ • S•••D1O.. 1112•••• ConUOI".....,0 O.

/ ...DMOHEV02.,. A4.,.

16.,. AS.,.010.,. .'2"10• Control..--0 a -

••• :It •••••...•....•~D I •....•.•••••

1134512345_.Of .."

Fig. 4 - Relationship between concentration of DMDHEUadd-on and area ahrinkqe for (a) 100",4 jute fabric and jute-rayon (60:40) blended fabric, (b) 100"k jute fabric on succes-sive washing, and (c) jute-rayon (60:40) blended fabric on

successive washing

of cloth in warp-way thus causes an increase incrimp of the warp threads. In a similar way, theweft crossing threads also resist extension and thecloth contracts weft-way.

It was earlier reported':" that the tensilestrength of the fabric is reduced by crosslinking.Andrews et aL5 reported that both the tensilestrength and the elongation at break of the cottonfabric are reduced by crosslinking. The reason forthis is that the crosslinking agent crosslinks be-tween the hydroxyl groups of amorphous regions,filling the intramolecular spaces therein. Conse-quently, the jute fibres in the amorphous regionsbecome less elastic and behave like orderlyoriented regions. giving some compactness likethat of crystalline region. This ultimately givesanti-shrink or anti-elongation properties in the treat-ed fabrics. It is also postulated=" that the cross-

167

INDIAN J. TEXT. RES., VOL. 14, DECEMBER IYK':I

linking treatments restrict the swelling of the fibrein water and with the increase in resin add-on, theability of fibre to swell in water decreases. As aresult, the crosslinked fabric resists to change indimensions. The results are in conformity withthose of Andrews et al" on knitted fabric.

•

4 Conclusions4.1 Crosslinking of jute and jute-rayon blended

fabrics with DMDHEU reduces the shrinkageof fabrics after washing or laundering and theeffect is pronounced for all the concentrationsof DMDHEU studied. However, the optimumconcentration of DMDHEU is 6% for all-jutefabric and 8% for jute-rayon fabric.

4.2 Jute-rayon blended fabric shows marginallyhigher shrinkage than all-jute fabric aftercrosslinking .

4.3 The catalyst type has no significant effect onthe dimensional characteristics of jute andjute-rayon blended fabrics and all the catalystsstudied impart good dimensional stability.

4.4 There is no relationship between warp-wiseand weft-wise shrinkage. To describe dirnen-

J6X

sional stability of the fabric qualitatively, the% area shrinkage would be appropriate forjute and jute-rayon blended fabrics.

AcknowledgementThe authors would like to express their thanks

to Dr S.R. Ranganathan, Director, UIRA, for val-uable criticism and interest during the study.

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