IndianJournalof Fibre & TextileResearchVol.17. March ICJ92. pp. 15-22

Properties of jute-synthetic union fabrics

A K Mukhopadhyay.S K Bose& U Mukhopadhyay"

IndianJute Industries'ResearchAssociation,17, Taratola Road, Calcutta700 088, IndiaReceived5 April 1991; revisedreceived14 August 1991; accepted3 September1991

The properties of jute-HOPE union fabrics of different constructions have been studied to find outsuitable light weight fabric for making bags for packaging. The combinations of2jute yarns and 1HOPEtape and I jute and 1 HOPE tape in warp give the best results in sacking and hessian quality fabricsrespectively without sacrificing much jute. Bags made out of these fabrics have been found to besatisfactory as revealed by drop test and other performances.

Keywords: Drop test performance, Fabric strength, Jute-HOPE union fabric, Packaging, Seam strength

IntroductionGlobal use of traditional jute fabrics has declined

drastically due to the competition with thepolyolefines (HDPE & PP) in the field of packaging,specially in the cement and fertilizer industries. Theuse of jute in packaging is expected to decline furtherunless the product is improved, made lighter andcheaper. Conventional jute products are heavier andstronger but less extensible than synthetics. They arecostlier too because of the high cost of raw jute, higherproduction cost and higher freight due to heaviness.However, jute bag has a number of plus points. It isbiodegradable and can be stacked to greater heightsthan synthetic bags and has much superior hookingresistance. Keeping all these aspects in view it appearsthat jute-synthetic union cloth, if properlydeveloped, will help to regain some of the markets lostto jute. Bags made of such union fabrics will not onlybe lighter than all-jute bags but will also have a betterlook and good features of jute.

Jute-synthetic union fabric can be woven in acircular loom but jute yarn can be used in such a loomin a very restrictive way at present. Moreover, most ofthe jute mills are not equipped with circular looms atpresent. Union fabrics can be manufactured in theexisting flat-bed jute loom also; the method ofmanufacturing jute-PP union fabrics has alreadybeen described in a paper! from this laboratory.However, the above study was restricted to usingsynthetic tapes either wholly in the warp or wholly inthe weft. No systematic study has yet been made toassess the behaviour of different combinations of jute

a Present address: Institute of Jute Technology.Ballygunge,CircularRoad. Calcutta 700 019

and synthetic yarns in the fabrics, nor has anyguideline been suggested to optimize the unionconstruction for a required end use performance. Thepresent paper deals with the development of suchfabrics of various qualities and analyzes theirdifferent physical properties. Some of the fabricconstructions have been optimized and theperformance of bags made out of such fabrics hasbeen studied.

2 Materials and Methods

2.1 Preparation of Fabric SamplesUnion fabrics of sacking and hessian qualities

were prepared in a member mill. For this purpose,normal jute yarns ofhessian quality (8t lb/spyndle inboth warp and weft) and sacking quality (10Ibjspyndle in warp and 22 Ibjspyndle in weft) wereused. The HOPE tapes of800 denier were used in thewarp only. In the earlier study, the warp beamcontained either all-jute or HOPE or PP yarn.However, in this case, warp beams with both jute andHDPE in different predetermined combinationshave been tried. For this purpose, the conventionalwarping (beaming) system of a jute mill was used. Inthe weft, conventional jute cops were always used.Fabrics were calendered in the conventional way in ajute mill. The following fabrics were made.

2.1.1 Sacking8 x \0 plain weave union fabrics were prepared

using 100% jute yarn of 22 lb/spyndle as wefts andjute-HOPE yarns (made from 10 lb/spyndle juteyarns and 800 denier HOPE tape) of followingcombinations as warps.

16 INDIAN J. FIBRE TEXT. RES., MARCH 1992

(i) 1 Jute/l HOPE(ii) 1 Jute/1 HOPE12 Jute/1 HDPE (Consecutive

four healds contain I Jute, I HOPE, 2 Jute, IHOPE)

(iii) 2 Jute/I HOPE i.e. double warp jute andHOPE single

(iv) All HOPE in warp8 x 10 double warp plain all-jute fabric having

yarns of 10 lb/spyndle and 22lb/spyndle in warp andweft respectively was used as control fabric.

2.1.2 HessianUnion fabrics in hessian quality with II x 12

construction were made using 100% jute yarn of 8!lb/spyndle as weft and jute-HDPE yarns (made from81 lb/spyndle jute yarn and 800 denier HOPE tape) ofthe following combinations as warps.

(i) I Jutejl HOPE(ii) I Jute/I HOPE/2 Jutejl HOPE(iii) All HOPE tapeHessian cloth (II x 12; 10 oz/40 in) was used as

control fabric.

2.2 TestsStandard method of tests I - 5 were followed to

determine the weight/m-, thread/dm, cover factor,drop test performance and seam strength. The othertests were made as follows.

The tensile strength offabric was determined on aravelled strip specimen of 100mm width by keeping adistance of200 mm between the grips of Goodbrand'smachine. Ravelled fabric specimen of 50 mm x 150mm were used between grips of Instron tensiletester. In both the cases, the time of break was main-tained at 20 ± 5 s. Ten tests were performed onwarp- and weft-way cloth specimen.

Ballistic work of rupture was measured bybreaking a ravelled fabric specimen of I in width at agrip length of 12 in. The sample was broken suddenlyby a falling weight and the loss in momentum of theweight due to breaking of the sample was taken as themeasure of the ballistic work of rupture.

Bursting strength was measured by theGoodbrand's pnumatic pressure method witheffective sample area of 15.5 in-. The pressurerequired to break the sample was recorded inpounds/in".

Air permeability was measured using W&LEgurley air permeometer with effective sample area of 4in? and the amount of air passing per min per ftz wasrecorded.

3 Results and DiscussionThe properties of the hessian quality union fabrics

are given in Table 1 and that of sacking quality inTable 2. It is observed that the hessian and sackingquality union fabrics are lighter than all-jute fabricby about 12-30% and 39-47% respectively.

In sacking quality, the decrease in the weight ofunion constructions as compared to the control OWfabric was due to the following facts.

(i) Control fabric was double warp (OW)tarpaulin fabric i.e. each split contained two juteyarns.

(ii) 1 Jute/I HOPE means that in a single splitinstead of a double warp jute yarn one single jute yarnand a HOPE tape were used i.e. for every four juteyarns in the warp in the control there were one juteyarn and one tape in the first experimental fabricwhereas in the second experimental fabric (1 Jute/IHOPE/2 Jute/I HOPE), for every eight yarns therewere three jute yarns and two tapes and in the thirdfabric (2 Jute/I HOPE), for every four jute yarns therewere two jute yarns .and one tape. The differentcombinations in the warp are shown in Fig.I.

However, in the case ofhessian quality, the unionconstructions were compared with the controlconsisting of single warp yarns instead of doublewarp, but in the fabric having I Jute/I HOPE/2 Jute/IHOPE combination, single and double warp yarnswere alternately used. For this reason, the weight ofthis particular fabric was higher than that of thecontrol hessian fabric.

3.1 Tensile PropertiesTables I and 2 show that there is a significant

reduction in breaking load in warp direction for bothhessian and sacking qualities but the tensile strengthin the weft direction is more or less unchanged. This isbecause of the lower strength of the HOPE tapes usedin the warp. However, even though the breaking loadis lower, the breaking extension is significantly higher(as may be observed from the load elongation curve inFig.2) which gives a higher ballistic work of rupture.In packaging applications, it is the ballistic work of

SACKING HESSIAN

~

~

~

~=0- Jut•• yarn =T - HOPE Tape

Fig. I· -Different combinations of jute yarn and HDPE tape inthe warp direction

.....-

Tabl

e1-

Prop

ertie

sof

hess

ian

qual

ityun

ion

fabr

ics

[Con

stru

ctio

n,II

x12

;Wef

t,8t

Ih/s

pynd

leju

te;

All-

jute

war

p,8t

Ib/s

pynd

Je;

Jute

-HO

PEw

arp,

8tJb

/spy

ndJe

jute

and

800

deni

erH

OPE

)

~Sa

mpl

eW

t/ml

at16

%Th

read

s/dm

Rat

ioof

jute

/A

irpe

rmea

bilit

y,C

over

Bur

stin

gst

reng

thB

allis

ticw

ork

ofTe

nsile

stre

ngth

,le

gm

oist

ure

rega

in.

gsy

nthe

ticin

war

pIV

/rnin

/ftl

fact

orlb

/in!

rupt

ure,

in-lb

(%re

duct

ion)

!:I':: :c

(%re

duct

ion

inw

t)W

arp

Wef

tdi

rect

ion

(%im

prov

emen

t)%

(%im

prov

emen

t)(%

impr

ovem

ent)

0(P

orte

r)(S

hots

)W

arp

Wef

t::

By

By

War

pW

eft

0nu

mbe

rw

eigh

t~

All-

jute

cont

rol

fabn

c'<

283

46.0

48.2

100:

010

0:0

Abo

veth

e84

.244

.041

.038

.576

.75

63.4

5"..•

(-)

(10.

8)(1

2.2)

max

imum

read

able

(-)

(-)

(-)

;:, ,...va

lue

390

(-)

~IJ

ute/

IH

OPE

inw

arp

and

250

44.8

48.8

50:5

090

:10

168

92.9

46.8

71.8

32.4

43.4

657

.05

I

allj

ute

inw

eft

(7)

(75.

1)(1

5.8)

(44)

CIl

(II.

7)(1

0.5)

(12.

4)(5

7)-< ~

87:1

388

.854

.871

.436

.155

.763

.9I

Jute

/IH

OPE

/2Ju

te/I

295

4649

60:4

010

0~

HO

PEin

war

pan

dal

ljut

e(±

4.2)

(10.

8)(1

2.4)

(59)

(25)

(74.

1)(-

6.2)

(27)

oin

wef

t~

All

HO

PE(8

00de

nier

)in

192

44.0

49.2

0:10

00:

100

197

80.8

54.6

•51

.551

.40

57.3

5s

war

pan

dal

lju

tein

wef

t(3

2.2)

(10.

3)(1

2.5)

(49)

(25)

(33.

8)(3

4)~ tI:

I is•

Unb

reak

able

due

tohi

ghel

onga

tion

o CIl

--~

,rf:;

;-~

;~

lr>

«\"\

.>;(

,":

')."

q•.

.•.

.;(.1

j..u

,))'\

'7:1:

l.c...

.j~

~(

~~.

)-~

~

~~

(~

~)

~l

~l~

0)

.~~l

..:...

("~)

;;'~

_~~'

l\.~

....?

'4 ~

~ -..I

I-' 00

Tabl

e2-

Prop

ertie

sof

sack

ing

qual

ityun

ion

fabr

ics

[Con

stru

ctio

n,8

x10

;Wef

t,22

lb/s

pynd

leju

te;

All-

jute

war

p,10

lb/s

pynd

le,

Jute

-HO

PEw

arp,

10lb

/spy

ndle

jute

and

800

deni

erH

OPE

]

Sam

ple

Wt/m

2at

20%

Thre

ads/

dmR

atio

ofju

te/

Air

perm

eabi

lity,

Cov

erB

urst

ing

stre

ngth

Bal

listic

wor

kof

Tens

ilest

reng

th,

kgm

oist

ure

rega

in,

gsy

nthe

ticin

war

pft3

/rnin

/ft2

fact

orIb

/in2

rupt

ure,

in-l

b(%

redu

ctio

n)

~(%

redu

ctio

nin

wt)

War

pW

eft

dire

ctio

n(%

impr

ovem

ent)

%(%

impr

ovem

ent)

(%im

prov

emen

t)(P

orte

r)(S

hots

)W

arp

Wef

t:>

By

lJy

War

pW

eft

Znu

mbe

rw

eigh

t~ 'll 53

All-

jute

doub

lew

arp

688

6839

100:

010

0:0

122

98.6

100.

456

5689

.5-

f;lco

ntro

lfa

bric

(-)

(8.0

)(9

.9)

(-)

(-)

trl ><I

Jute

/IH

OPE

inw

arp

418

33.6

43.8

50:5

096

:41)

898

.586

.459

.863

.143

.45

106.

4!""

'l

and

allj

ute

inw

eft

(39.

2)(7

.9)

(l1.1

)(1

9.7)

(14)

(6.8

)(1

2.7)

(52)

f;l "Vl

1Ju

te/I

HD

PE/2

Jute

/l37

233

.641

.260

:40

95:5

8098

.068

.868

.263

.854

.75

99.9

~ >H

OPE

inw

arp

and

allj

ute

(45.

9)(7

.9)

(10.

5)(3

4.4)

(31)

(21.

8)(1

3.9)

(39)

;II::l o

inw

eft

::t .... \0

2Ju

te/I

HD

PEin

war

p41

934

41.4

70:3

096

:473

98.9

68.0

78.5

64.3

71.4

510

8.4

\0 N

and

all

jute

inw

eft

(39.

1)(8

.0)

(10.

5)(4

0.2)

(32)

(40.

2)(1

4.8)

(21)

All

HD

PEin

war

pan

dal

l36

233

.245

.00:

100

0:10

022

097

.969

.873

.069

.544

.95

130.

9ju

tein

wef

t(4

7.4)

(7.4

)(1

1.4)

(-80

.3)

(30.

3)(2

4.1)

(50)

MUKHOPADHYAY et al.: JUTE-SYNTHETIC UNION FABRICS 19

90Jute

80

70

6001

.0<

.; 5000...J

01 40~.0<0~ 30

!Xl

20

10

0

r-- Jutl'l HOPE:, (2: 1)

I Jutl'/HOPE/Jut~/HOP( 1. 1 2.1)

l-ig. 2 Load-elongation curve of jute-HDPE union fabricwhen load was applied in the warp direction

(a)Fig. 3 Rupture pattern of (a) control and (b)jute-HDPE union

fabric when the load was applied in the weft direction

rupture which is a more important criterion than thebreaking load because it determines the impactresistance of the fabric. For this reason, the drop testperformance (which is a good indication of thebehaviour ofa bag) is not inferior to that ofa all-jutebag (Table 3) even though the weight of the bag issignificantly lower. The ballistic work of rupture(BWR) for union fabric is significantly higher thanthat for the corresponding all-jute cloth, both forhessian and sacking varieties, in the warp directiondue to the inclusion of synthetic tapes. Improvementin the weft direction is marked only when all-HOPEtapes are used in the warp in both the hessian andsacking varieties. This may be due to the fact that sincethe HOPE tapes used were flat they offered moreinterlacing effect. It is also interesting to note from

Fig.3 that the rupture pattern in union fabric is morelocalized compared to that in all-jute fabric where theyarn breaks are spread over the entire zone betweenthe grips. In union fabrics, the tapes are more easilydragged by the broken yarns due to lesseryarn-to-tape friction and this releases the interlacingfriction. As a result, the other yarns in or near thecross-section tend to break. In the case of all-jutefabric, however, because of the much higheryarn-to-yarn friction the warp yarns are not so easilydragged by the broken yarns as the two grips separateand as such other yarns may not break along thesame cross-section but may break at weak pointselsewhere.

3.2 Drop Test Performance and Seam StrengthUnion fabrics gave improved performance In

BWR and increased energy of rupture during tensileloading. Bags were made out of these fabrics and droptest performance and seam strength were tested. Forsacking, 50 kg of cement and for hcssian, 50 kg of ricewere used as packing materials.

3.2.1 SackingTable 3 shows the drop test performance of

cement bags made out of union sacking cloths. It isobserved from this table that the union bags are28-40% lighter in weight than the correspondingall-jute bags. This is a remarkable improvement fromthe freight point of view. Th~ drop test performanceof the union sacking bags having 2 Jute/I HOPEcombination in warp is excellent and there is nobreakage even after a drop from 12ft height. The bagsmade from other combinations of jute-HOPE arealso excellent or at least not inferior to all-jutesacking bag. The only thing is that the side seamstrength is very low. In cases where the percentage ofHOPE is more than 50'Yoby number. some fracture ofthe bags is observed which is mostly due to theslippage of HOPE yarns from under the scam. Thebottom seam strength of these union bags iscomparable to that of all-jute bag. However. thelow side scam strength did not affect the drop testperformance of the union bags and there is somescope for the improvement of this low side seamstrength by further modification of scam. Theseepage of union sacking bags. except for a few cases,is comparable to that of all-jute bag.

3.2.2 Hessian

The union bags made out of the hessian variety ofvarious Jute/HOPE combinations are 10-30%lighter in weight than the all-jute bags. The drop testperformance (Table 4) of the union bags of all

51 c/ ~ I

/-r- I ~

20 INOIAN J. FmRE TEXT. RES., MARCH 1992

Table 3-Particulars of bags made from sacking quality union fabrics and their drop test performance and seam strength[Fabric construction, 8 x 10; packing material, 50 kg cement; Weft, 22lb/spyndle jute; All-jute warp, 10 lb/spyndle; Jute-HOPE warp,

10 Ib/spyndle jute and 800 denier HOPE]Parameter Bag sample No.

I 2 3 4 5Dimension, em" 73.5'x49.1 73 x 47.4 71.2 x SO.5 72.5 x 50.6 73.2 x 49.1Weft Jute Jute Jute Jute JuteWarp All jute! I Jute/ l HOPE I Jute/I HOPE/ 2 Jute/I HOPE All HOPE

2 Jute/I HOPEBag weight at 20% moisture regain, g 563 326 301 402 307Ends/dm 68.6 34.0 42.0 51.0 33.0Picks/dm 38.2 42.4 41.4 40.6 43.8Stitches/drn 9-1\ 9-11 9-1\ 9-11 9-1\Tensile strength (5 x 20 cm-), kg

Warp 107 49 57 66 51Weft 147 100 127 140 145

Seam strength

Side seam, kg 62 10" 20" 32" IS"No. of twine-cloth edge break 5-0-0

Bottom seam. kg 56 58 54 54 51No. of twine-cloth edge break 5-0-0 5-0-0 5-0-0 5-0-0 5-0-0

Drop testNo. of bags tested 5 5 5 5 5No. of bags failed nil 5 nil nil 5No. of drops to cause bad damage 6 6No. of bags not damaged after 6th drop 5 nil 5 5 nil

(height, 12 ft)Av. seepage

% Loss (height, 6 ft) 0.20 0.20 0.66 0.32 0.34% Loss (height, 12 ft) 0.32 0.96 0.46

Distribution of bags tested in IJIRA grading" Excellent Good Excellent Excellent Good

"Slippage of yams from seam.bIJI RA grading scheme: Burst on Ist or 2nd drop (height, 6 ft)--Poor performance; Burst on 3rd, 4th or 5th drop (height, 6ft)--Fairperformance; Burst on 6th drop (height, 12 ft}-Good performance; and No damage on 6th drop (height, 12 ft)-Excellentperformance.

combinations can be said to be satisfactory. Seepagein few of such bags was almost nil. It is very difficult tocomment on the seam strength because the clothstrength varies widely. So, the seam efficiency- hasbeen considered and it is found that the efficiency ofboth side and bottom seams of the bag with 1 Jute!1 HDPE combination is highest.

3.3 Air PermeabilityThe air permeability of the union fabrics is, in

general, less than that of the corresponding all-jutefabric by 20-40%. This might be due to the highercover offered by the flat HDPE tapes in the fabric. Thechange in cover factor, however, could not berepresented by the conventional photo-electric

method due to the transparent nature of the tapes.However, it is interesting to note that the airpermeability of union fabric having 100% HDPE inwarp is significantly higher than that of all-jutefabrics. This may be due to less cohesiveness of theHDPE tapes in the fabric. The change in airpermeability is more marked in hessian than insacking quality.

3.4 Bursting StrengthIn hessian quality, the bursting strength increased

by 7-20% whereas in sacking quality, it decreased by30-35% (Tables I and 2). This anomaly in due to therelative difference in the strength of jute yarns andHDPE tapes. Sacking jute yarns are relatively

MUKHOPADHYAY et al.: JUTE-SYNTHETIC UNION FABRICS 21

Table 4-Particulars of bags made from hessian quality union fabrics and their drop test performance and seam strength

[Fabric construction, II x 12; packing material, 50 kg rice; Weft, 81 Ib/spyndlejute; All-jute warp, 81 lb/spyndle.jute-Hffl'E warp. 10lb/spyndle jute and 800 denier HOPE]

Parameter Bag sample No.

Dimension, ern?WeftWarp

Bag weight at 16% moisture regain, gEnds/dmPicks/dmStitches/dmTensile strength (10 x 20 cm-), kg

WarpWeft

Seam strengthSide seam. kg

No. of twine-cloth edge breakBottom seam, kg

No. of twine-cloth edge breakSeam efficiency

WarpWeft

Drop testNo. of bags testedNo. of bags failedNo. of drops to cause bag damageNo. of bags not damaged after 6th drop

(height. 12 ft)Av. see page

% Loss (height. 6ft.)% Loss (height. 12 ft.)

Distribution of bags tested in U 1RA grading"GoodExcellent

"Slippage of yarns from seam.bUIRA grading scheme (see Table 3)

2 3 4

103.2 x 58.0 103.3 x 57.6 103.5 x 56.4 103.9 x 57.8Jute Jute Jute Jute

All jute 1 Jute/J HOPE 1 Jute/I HDPE/ All HOPE2 Jute/ l HDPE

381 317 360 23945.5 45.0 56.0 43.5

48.0 48.5 49.0 50.010 10 10 10

138 98 118 156123 79 108 104

37 29" 32" 23"0-0-5

37 33 34 340-0-5 0-0-5 0-0-5 0-0-5

54 59 54 2960 84 63 65

3 3 3 3nil 2 I nilnil 6 6 nil3 I 2 3

1% nil 1% nil

32I 3

I

2

stronger than the hessian yarns. So, when the fabricsare subjected to more air pressure the HOPE tapesbulge more in sacking than in hessian, allowing moreair to pass and leading to lower bursting strength.

4 ConclusionsJute-HOPE union fabrics prepared with various

combinations of jute yarn and HOPE tapes giveimproved properties as compared to thecorresponding all-jute fabrics. Among all thecombinations studied, 2 Jute/ l HOPE gives the bestresult in sacking and 1 Jute/I HOPE in hessian

without sacrificing much jute. The cement bags madeout of the various combinations of jute and HOPEand having a HOPE film laminated inside byapplication of heat, are much lighter than those madeout of all-jute cloth. The increased energy of rupture(from load-elongation curve) indicates that thesetypes of fabric, even though they are lighter, canwithstand a higher load. The inclusion of synthetictape in hessianjute fabric opens the possibility of spotbonding of LOPE or LLOPE film for lamination.This type oflamination will completely avoid the useof bitumen for lamination in making fertilizer bags.

22 INDIAN J. FIBRE TEXT. RES., MARCH 1992

AcknowledgementThe authors are grateful to Dr A C Mukherjee and

Mr J Bera for help in a few tests.

ReferencesI Aditya R N & Sarkar A, Indian Text J. XCV (1985) 95.

2 Bose S K & Mukhopadhyay U, Indian} Text Res, 12 (1987)194.

3 Indian standard specifications IS:2387 (Indian StandardsInstitution, New Delhi), 1969.

4 Indian standard specifications IS: 1963 (Indian StandardsInstitution, New Delhi), 1981.

5 Mukhopadhyay U, Text Trend. 8 (1965) 37.