textile research journal
DESCRIPTION
pengajaran dari textileTRANSCRIPT
-
XML Template (2012) [7.2.20123:53pm] [112]{SAGE}TRJ/TRJ 435851.3d (TRJ) [PREPRINTER stage]
Article
Investigation of wicking, wetting anddrying properties of acrylic knitted fabrics
Meltem Yanlmaz and Fatma Kalaoglu
Abstract
In this study, it was aimed to investigate the relationship between different knitted structures and some thermo-
physiological comfort parameters. Wetting, wicking and drying properties of single jersey, 1 1 rib, 2 2 rib andinterlock knitted fabrics made out of acrylic yarns were studied and experimental wicking height, wicking weight, transfer
wicking ratio, contact angle and WER (water evaporation rate) values were measured. Samples were produced in two
different tightness values to obtain slack and tight fabrics for all structures. Some comfort-related parameters were
correlated with structural parameters of fabrics such as fabric tightness factor, thickness, porosity, loop length and pore
size etc. The statistical analysis results indicate that the effect of the knitted structure is significant for wicking height,
wicking weight, contact angle values, transfer wicking ratios and WER values. Wicking height increases depending on
knitted structures namely, single jersey, 1 1 rib, interlock and 2 2 rib, respectively. Slack fabrics have longer looplengths with higher porosity values and higher pore sizes for all knitted structures. Slack structures of 2 2 rib, 1 1 rib,interlock and single jersey knits have higher transfer wicking ratios when compared with their tight structures. WER is
inversely related with fabric thickness. It decreased with an increase of thickness due to increase of compactness and
decrease of air space. All tight knitted structures have higher contact angles than their slack forms due to compactness of
the surface.
Keywords
comfort, acrylic, knitted structures, wicking, drying
Introduction
Knitting structures are important due to several advan-tages such as comfort, high elasticity, conformity withthe shape of the body, softer touches, lightweight,warmth, wrinkle resistance, and ease of care. etc. It iswell known that the physical properties of fabrics aredependent on their yarn properties and fabric construc-tion parameters. Construction parameters, such as ne-ness of yarns, density and the type of knitted structure,control the texture and surface topography offabrics.15
Thermo-physiological comfort is one of the consid-erations of clothing comfort. The thermo-physiologicalcomfort of a garment is related to several parameters:lightness, thermal resistance, heat and water vaportransport, sweat absorption, wind impermeability anddrying. Investigating the relationships between fabricstructure and permeability to water vapor/water (i.e.sweat) is stimulating interest. The ability of clothing
materials to transport moisture vapor is important todetermine wear comfort. Absorption of sweat and itstransportation through and across the fabric are relatedto clothing comfort properties of the fabrics.611
Drying time is another important aspect while deter-mining a comfort level.12 There is a general agreementthat fabric thickness, density and porosity are criticalfactors to determine comfort perceptions.1315 Yoonand Buckley16 reported that steady state moisturevapor transport through fabrics is controlled by a dif-fusion process that is inuenced by fabric structure,fabric thickness and openness.
Textile Engineering, Istanbul Technical University, Turkey
Corresponding author:
Meltem Yanlmaz, Textile Engineering, Istanbul Technical University,
Gumussuyu 34437, Istanbul, Turkey
Email: [email protected]
Textile Research Journal
0(00) 112
! The Author(s) 2012Reprints and permissions:
sagepub.co.uk/journalsPermissions.nav
DOI: 10.1177/0040517511435851
trj.sagepub.com
at Universiti Tun Hussein Onn Malaysia on April 5, 2015trj.sagepub.comDownloaded from
-
XML Template (2012) [7.2.20123:53pm] [112]{SAGE}TRJ/TRJ 435851.3d (TRJ) [PREPRINTER stage]
Higher wicking properties oer a drier feeling by thespreading of the liquid fast.1719 Fiber must be wettedbefore wicking. If ber is not wet by a liquid, the liquiddoes not wick into a fabric. Wetting is determined bythe surface properties of the bers and the wettingliquid, whereas wicking is also aected by the wayand arrangement of the bers or yarns. To determinewetting and wicking properties, pore size and numberof pores in the fabric structure is important.20,21
Porosity is one of the main physical parameters thathave a great inuence on thermo-physiological comfortproperties.1,22 The porosity of a knitted structure willinuence its physical properties, such as its bulk den-sity, moisture absorbency, mass transfer and thermalconductivity. The yarn diameter, the surface formationtechniques and the number of loop counts per unit areaare the main factors aecting the porosity of textiles.2
Besides pore structure, the ber surface properties arethe main determinants of wicking properties.23 Theevaluation of contact angle between a liquid and asolid surface indicates wettability, changes in the levelof surface energy, and changes in the chemical andsupermolecular structure of the surfaces. Textile sur-faces are rough; depending on the structure of the inter-lace of yarn strands, the bers inll and theirarrangement in the product.24
Hasan et al.4 reported that topographical character-istics of the fabrics strongly depend on their construc-tion parameters such as the type and neness oflaments, yarn neness, yarn density, warp and weftdensity and the type of weave. Oglakcioglu et al.25
investigated thermal comfort properties of some knit-ted structures (single jersey, 1 1 rib, interlock) andreported that each knitted structure tends to yieldrather dierent thermal comfort properties. Ucaret al.26 investigated the eects of rib design on thermalproperties of rib fabrics by using three dierent ribstructures (1 1, 2 2, 3 3) and reported that withincreasing density, air permeability and heat lossdecreases. Ramachandran et al.27 investigated thethermal behavior of ring and compact spun yarnsingle jersey, rib and interlock knitted fabrics andstudied the relationship between thermal propertiesand some physical characteristics such as thickness,tightness factor, density and permeability. They con-cluded that the thermal properties show a decreasingtrend as the fabric thickness, tightness factor andfabric aerial density values increase. Emirhanovaet al.28 investigated the eects of the knitted structureon the dimensional and physical properties of winterouterwear knitted fabrics. Crow and Osczevski29
reported that the amount of water that wicked from
Table 1. The properties of fabric samples
Code
Short
code
Fabric
structure
Thickness,
mm
Weight per
unit area,
g/m2
Loop
length,
cm
Stitch
density,
loops/cm2
Tightness
factor,
tex1/2/cm
Porosity,
%
Pore
size, cm
Stiffness
(Newton/
cm2)
SJ-Slack SJ-S Single jersey 1.72 0.07 326.8 0.890 4.42 6 26.52 9.494 0.702 0.101 0.438028SJ-Tight SJ-T Single jersey 1.768 0.07 342.2 0.780 4.40 7 30.8 10.833 0.705 0.094 0.538221R(1 1)-Slack 1 1R-S 1 1 rib 2.152 0.01 365.5 0.630 9 8 72 13.413 0.542 0.058 0.498561R(1 1)-Tight 1 1R-T 1 1 rib 1.934 0.07 394.5 0.477 11 11 121 17.715 0.352 0.042 0.567444Int-Slack Int-S Interlock 2.45 0.08 429.1 0.300 11 8 88 28.167 0.766 0.051 0.93273Int-Tight Int-T Interlock 2.454 0.07 519.1 0.290 12.2 9 109.8 29.138 0.723 0.046 1.350201R(2 2)-Slack 2 2R-S 2 2 rib 2.778 0.03 391 0.563 12 9 108 15.009 0.525 0.033 0.37332R(2 2)-Tight 2 2R-T 2 2 rib 2.734 0.09 483 0.525 12.3 10 123 16.095 0.487 0.029 0.567444
0 90.40.80.70.60.50.40.3
30
25
20
15
10
Loop length
Tigh
tnes
s Fa
ctor
0.90.80.70.60.50.3
0.110.100.090.080.070.060.050.040.030.02
Loop length
Pore
size
0.90.80.70.60.50.40.3
1.4
1.2
1.0
0.8
0.6
0.4
0.2
Loop lengthSt
iffne
ss
Figure 1. Correlation of loop length with tightness factor, pore size and stiffness.
2 Textile Research Journal 0(00)
at Universiti Tun Hussein Onn Malaysia on April 5, 2015trj.sagepub.comDownloaded from
-
XML Template (2012) [7.2.20123:53pm] [112]{SAGE}TRJ/TRJ 435851.3d (TRJ) [PREPRINTER stage]
one layer to another depended on the pore sizes andtheir volumes. Zhuang30 reported that the amount oftransferred water largely depends on the performanceof individual fabrics as well as the way in which theycontacted.
There are some reports in the literature about com-fort properties of knitted structures, but there is nodetailed study about wetting, wicking and dryingproperties of dierent knitted structures made ofacrylic yarns. In this study, acrylic yarns were usedto prepare four dierent knitted structures (singlejersey, 1 1 rib, 2 2 rib and interlock), with eachstructure prepared at two dierent tightness levels(slack and tight). Several fabric parameters were mea-sured and comfort parameters were tested to investi-gate the correlations between fabric parameters andcomfort properties.
Experimental
The fabric samples were produced using 28/2 Nmacrylic yarns. Single jersey, interlock, 1 1 rib and2 2 rib fabric samples were knitted in two dierenttightness levels, i.e. slack and tight, with the samemachine settings. The specimens were knitted with thesame yarn tension and cam setting by using 7 ne, 672needle Shima Seiki SES 124S V bed at knittingmachine. Before the measurements and tests, the sam-ples were conditioned in standard atmospheric condi-tions (20 2C, 65 5% relative humidity) for twodays. All tests were carried out in standard atmosphere.Fabric tightness factor were determined by the equa-tion (TFT1/2/l; where T is the linear density of yarnin tex and l is the loop length in cm) used byRamachandran et al.27 Porosity and pore size values
Table 2. Experimental wicking height, wicking weight, transfer wicking ratio, contact angle and WER values
Wicking height at 10 min, mm Wicking weight, g
Transfer
wicking
ratio, %
Contact
angle, WER at
75 min
Number Code
Short
code
Wale-
wise
Course-
wise
Wale-
wise
Course-
wise
1 SJ-Slack SJ-S 12.07 0.09 10.63 0.07 3.013 0.11 3.004 0.08 14.77 0.17 73.6 0.876 0.052 SJ-Tight SJ-T 11.20 0.08 10.93 0.18 2.932 0.12 2.930 0.25 10.78 0.2 88.93 0.869 0.053 R(1 1)-Slack 1 1R-S 12.37 0.04 9.62 0.07 3.384 0.08 3.039 0.14 14.98 0.17 75.69 0.847 0.084 R(1 1)-Tight 1 1R-T 12.13 0.09 9.67 0.07 3.042 0.05 2.793 0.05 4.65 0.28 96.4 0.841 0.035 Int-Slack Int-S 12.53 0.17 11.67 0.07 4.268 0.08 4.212 0.07 6.81 0.20 71.14 0.784 0.076 Int-Tight Int-T 12.27 0.12 12.40 0.07 4.238 0.07 3.392 0.06 5.53 0.21 76.79 0.710 0.087 R(2 2)-Slack 2 2R-S 13.10 0.09 10.40 0.57 4.068 0.12 3.248 0.07 32.25 0.28 99.01 0.693 0.068 R(2 2)-Tight 2 2R-T 12.90 0.09 10.30 0.07 3.917 0.04 3.340 0.09 28.40 0.18 118.26 0.705 0.02
Figure 2. Vertical wicking curves for wale-wise directions.
Yanlmaz and Kalaoglu 3
at Universiti Tun Hussein Onn Malaysia on April 5, 2015trj.sagepub.comDownloaded from
-
XML Template (2012) [7.2.20123:53pm] [112]{SAGE}TRJ/TRJ 435851.3d (TRJ) [PREPRINTER stage]
were calculated according to Benltoufas formula1 andOgulatas formula,2 respectively.
The porosity (" 1 (yarn volume/total volume)) iscalculated according to the formula below:
" 1 d21CW=2t
where t is sample thickness (cm), l is loop length (cm), dis yarn diameter (cm), C is the number of courses percm, W is the number of wales per cm.1
The pore size is calculated by using rp [(t-Slpry2)/ptS]1/2 where rp is pore radius, t is thickness, S is cw,l is loop length.2
To determine vertical wicking properties of the fab-rics, a method stated in the literature31 was used. Thespecimens were cut along the wale-wise and course-wisedirections (200mm 25mm). They were suspended ina reservoir of distilled water. The bottom ends of thespecimens were immersed vertically at a depth of 3 cminto the water. The wicking heights were measured andrecorded every minute for 10min to evaluate the wick-ing ability. Transfer of wicking properties were mea-sured according to the stated method.30 Thespecimens were cut into 7.45 cm diameter circles. Thespecimens were wetted and placed between two dishes.The dry specimens were put on the wet specimensand the specimens were weighed every 5min up to30min. The wet specimens were weighed before eachtest as mentioned in the literature.30
Drying capabilities were evaluated by calculatingwater evaporating rates (WER) as mentioned in thestudy of Fangueiro et al.31 The specimens were cut asa 200mm 200mm square and weighed. The waterwas used to wet the specimens. The amount of waterequals to 30% of the dry specimens. The specimens
were weighed and the change of weights were recordedto measure WER.
Information about wettability and solid-liquid con-tact geometry was obtained by measuring the deionizedwater contact angle using a contact angle meter(Attension theta optical tensiometer). First the speci-men was placed on the sample stage. Then, a drop ofwater was deposited on the fabric surface. The imageswere recorded and analyzed by the software(OneAttension Software). The measurements wererepeated three times for each sample. The looplength, the number of wales per cm, the number ofcourses per cm, the thickness and the weight of fabricswere measured according to relevant standards (TS EN14970, TS EN 14971, TS EN 7128, ISO 5084, TS 251).Stiness of the specimens were measured accordingto ASTM International, Designation D 4032-94:The Standard Test method for Stiness of fabricby the Circular Bend methods, (2001). Statistical anal-yses have been carried out by using SPSS 18 andMinitab15.
Figure 3. Vertical wicking curves for course-wise directions.
Table 3. Correlation coefficients and p-values for wicking
heights
Dependent-independent
variables
Pearson
correlation
coefficient p-value
Wicking height-pore size 0.781 0.022Wicking height-porosity 0.798 0.018
Wicking height-stiffness 0.838 0.009
Wicking height-thickness 0.859 0.006
Wicking height-density 0.686 0.003
4 Textile Research Journal 0(00)
at Universiti Tun Hussein Onn Malaysia on April 5, 2015trj.sagepub.comDownloaded from
-
XML Template (2012) [7.2.20123:53pm] [112]{SAGE}TRJ/TRJ 435851.3d (TRJ) [PREPRINTER stage]
Results and discussions
The properties of fabric samples are given in Table 1. Itcan be seen that the fabrics diered in terms of theknitted structure, the number of courses and walesper cm and loop length. The thickness of the fabricsvaried with the loop length and course count.Furthermore, tightness factor, porosity, pore size andstiness were reported in the Table 1.
The dimensional, weight and comfort-related prop-erties of knitted fabric are determined by the looplength.3 As shown in Figure 1, there is an inverse
correlation between the loop length and the tightnessfactor. The Pearson correlation coecient of looplength and tightness factor is 0.943 and the p-valueis 0.000. The higher value of the coecient shows theexcellence of relationship, and the p-value must besmaller than 0.05 to conclude that the result is signi-cant and meaningful.
There are also a correlation between loop length andpore size with the 0.743 Pearson coecient(p-value 0.000) and an inverse correlation betweenloop length and stiness (Pearson correlation coe-cient0.748, p-value 0.000) as shown in Figure 1.
Figure 4. Vertical wicking ability of the fabrics at 10 min, comparison of wale and course directions.
Figure 5. Vertical wicking weights.
Yanlmaz and Kalaoglu 5
at Universiti Tun Hussein Onn Malaysia on April 5, 2015trj.sagepub.comDownloaded from
-
XML Template (2012) [7.2.20123:53pm] [112]{SAGE}TRJ/TRJ 435851.3d (TRJ) [PREPRINTER stage]
Measured wicking height, wicking weight, transferwicking ratio, contact angle and WER values are pre-sented in Table 2.
Vertical wicking test results
Figures 2 and 3 show vertical wicking test results forwale and course-wise directions, respectively.Univariate analysis of variance results indicate that dif-ferent types of knitted structures have statistically sig-nicant eects on the vertical wicking ability of thesamples at a 95% condence interval for course-wisedirections (p 0.001) and wale-wise directions
(p 0.018). For the wale-wise direction, the order ofwicking heights of dierent knitted structures is thesame for slack and tight forms. The order is 2 2rib>interlock>1 1 rib>single jersey. Furthermore,the slack forms of the dierent knitted structuresshow better wicking ability than their tight forms.According to Figure 2, wicking heights increasedepending on the knitted structure namely, singlejersey, 1 1 rib, interlock and 2 2 rib, respectively.For course-wise direction, the order of wicking abilityof the dierent structures has changed (interlock>sin-gle jersey>2 2 rib>1 1 rib) and tight forms havehigher wicking compared to their slack forms.
The fabric structures such as single jersey, rib andinterlock, inuence the comfort properties of the knit-ted fabrics. It is, basically, because of fabric propertiessuch as fabric thickness, tightness factor, porosity, poresize, loop length and density change according to knit-ted structure. Benltoufa et al.1 indicated that liquidabsorbency are closely related to pore size and distri-bution. Wong19 reported that according to the capillaryprinciple, smaller pores are lled rst and inuence theliquid front movement. As the smaller pores are com-pletely lled, the liquid then moves to the larger pores.The distance of liquid advancement is greater in a smal-ler pore because of the higher capillary pressure. Theresults obtained in our study were similar. There is aninverse correlation between pore size and wickingheight. The Pearson coecients and p-values can beseen in Table 3. Wicking height for course-wise direc-tion are correlated with porosity and also correlatedwith stiness. Thickness is also correlated with wickingheight for our samples (Pearson coecient is 0.859,
Table 4. Correlation coefficients and p-values for wicking
weights
Dependent-independent
variables
Pearson
correlation
coefficient p-value
Wicking weight-loop length 0.777 0.000Wicking weight-density 0.604 0.013
Wicking weight-tiffness 0.574 0.02
Wicking weight-tightness factor 0.767 0.001
Wicking weight-thickness 0.553 0.026
Wicking weight-tightness factor 0.728 0.001
Wicking weight-porosity 0.521 0.039
Wicking weight-stiffness 0.515 0.041
Wicking weight-loop length 0.638 0.008Wicking weight-pore size 0.679 0.004
Figure 6. Transfer wicking ratios.
6 Textile Research Journal 0(00)
at Universiti Tun Hussein Onn Malaysia on April 5, 2015trj.sagepub.comDownloaded from
-
XML Template (2012) [7.2.20123:53pm] [112]{SAGE}TRJ/TRJ 435851.3d (TRJ) [PREPRINTER stage]
correlation is signicant at the 0.01 level (2-tailed) dueto p-value of 0.006). There is also a correlation betweenthe wicking height for wale-wise direction and the den-sity with the coecient of 0.686. Higher wicking heightsfor tight fabrics might be related to the comparativelyshorter loop lengths of the tight fabrics.
Figure 4 shows the vertical wicking heights of thesamples at 10 minutes for course-wise and wale-wisedirections. Textile structure and construction aredependent on the type of weave pattern, type of theber content, ber neness (ends/inch, picks/inch),and the yarn parameters. Wicking properties of textilefabrics is also inuenced by the surface roughness, theheterogeneity, the diusion of liquid into the ber, andthe capillary action of the ber assemblies. A number of
factors, especially fabric structure (yarn count, fabricdensity, weave design, porosity, ber content etc.)also eect wicking height.32 The samples show shorterwicking heights for all knit structures except forInterlock-tight sample for course-wise direction thanfor wale-wise direction. It might be related to dierentloop shapes and densities of the structures for wale-wiseand course-wise directions. Arrangement of yarns andvolume fractions of bers per unit area change depend-ing on directions so dierent trend was seen for dier-ent directions.
Figure 5 shows the vertical wicking weight values.According to statistical analysis, there is a correlationbetween vertical wicking weights and loop lengths forwale-wise direction. For wale-wise direction, wickingweights are correlated with tightness factor. Forcourse-wise direction there is a correlation betweenthe wicking weight and the tightness factor. Wickingweights and loop lengths are correlated. There is alsoan inverse correlation between the wicking weight andthe pore size with a Pearson coecient of 0.679. Asstated by Wong23 high liquid retention can be achievedby having a large number of large pores or a high totalpore volume. Porosity can be correlated with wickingweights for our samples (Table 4) as stated before byWong.
Transfer wicking test results
Figure 6 shows the transfer wicking test results. Thereare signicant dierences between transfer wickingratios of the samples. 2 2 rib structures have the high-est ratios (more than 25%). It can be seen from
2.82.62.42.22.01.81.6
0.5
0.4
0.3
0.2
0.1
Thickness, mm
Tran
sfer
wic
king
rat
ios
Figure 7. The relationship between transfer wicking ratio and
the thickness.
Figure 8. WER curves.
Yanlmaz and Kalaoglu 7
at Universiti Tun Hussein Onn Malaysia on April 5, 2015trj.sagepub.comDownloaded from
-
XML Template (2012) [7.2.20123:53pm] [112]{SAGE}TRJ/TRJ 435851.3d (TRJ) [PREPRINTER stage]
2.82.62.42.22.01.81.6
0.90
0.85
0.80
0.75
0.70
Thickness, mm
WER
at 7
5 m
in, %
Figure 9. Regression plot of WER vs thickness.
0.110.100.090.080.070.060.050.040.030.02
0.90
0.85
0.80
0.75
0.70
Pore size, cm
WER
at 7
5 m
in, %
a
12010080604020
0.90
0.85
0.80
0.75
0.70
Density, loops/cm2
WER
at 7
5 m
in, %
b
0.90.80.70.60.50.40.3
0.90
0.85
0.80
0.75
0.70
Loop length, cm
WER
at 7
5 m
in, %
c
3025201510
0.90
0.85
0.80
0.75
0.70
Tightness factor, Tex1/2/cm
WER
at 7
5 m
in, %
d
Figure 10. The relationship between (a) pore size, (b) density, (c) loop length, (d) tightness factor, and WER.
8 Textile Research Journal 0(00)
at Universiti Tun Hussein Onn Malaysia on April 5, 2015trj.sagepub.comDownloaded from
-
XML Template (2012) [7.2.20123:53pm] [112]{SAGE}TRJ/TRJ 435851.3d (TRJ) [PREPRINTER stage]
Figure 6 that transfer wicking ratio values of the sam-ples increase depending on knit structure namely, 1 1rib, interlock, single jersey and 2 2 rib, respectively.As can be seen in Table 1, slack fabrics have longerloop lengths with higher porosity values and higherpore sizes for all the knitted structures. Slack formsof 2 2 rib, 1 1 rib, interlock and single jersey struc-tures have higher transfer wicking ratios compared totheir tight forms. Similar results were reported fortransfer wicking of slack fabrics comparing them withtheir tight forms by Cil et al.33 who studied the eectsof the composition, the yarn number and the thicknesson some comfort properties of cotton-acrylic fabrics. Itwas concluded in Ramachandrans study that the mate-rial which has good transverse wicking will increase thewearing comfort21 and that the thickness of the mate-rial governs the transverse wicking. There is a correla-tion between the transfer wicking properties and thethickness for our samples (Figure 7, correlation coe-cient 0.507 p-value 0.045) as reported before in thestudy of Ramachandran.
Drying test results
Figure 8 shows the WER of the samples. ANOVAresults show that the dierence between the specimensis signicant with a 0.013 of p-value at a 95% con-dence interval. WER values of the samples, at 75min,increase depending on knitted structure namely, 2 2rib, interlock, 1 1 rib and single jersey, respectively.Slack structures have higher WER values compared totheir tight forms. The drying is related with the loopdensity of the knitted fabric and the drying time islonger for tight fabrics with higher loop densities forthe same fabric construction. Density is higher for 2 2rib fabric (for tight sample, the density is 123 loops/cm2). 2 2 rib structure has the lowest WER becauseof less air entrapped in the knit structure. It may be dueto the fact that the total contact area of bers holdingwater is higher for 2 2 rib fabrics because of higherber volume fraction in their knitted structure thanother structures.
The WER values show decreasing trend when thefabric thickness increases in all the cases. The statisticalanalysis results indicate that WER is correlated signif-icantly with fabric thickness as shown in Figure 9.Pearson correlation coecient of thickness and WERat 75min is 0.946 with p-value 0.000. The regressionequation is WER at 75 min 1.190.177 thickness,R2 89.4%, R2(adj) 87.7%. The inuence of thick-ness on WER is signicant because the correlationindexes, R2 and R2(adj), are properly .89 and .87. Thehigh value of the correlation index shows that the inu-ence of thickness on WER is high and expressiveness
of the relationship is also high and meaningfulstatistically.
WER decreases with the increase of the thicknessdue to increase of compactness and the decrease ofair space. Univariate analysis of variance resultsreveal that at the 0.01 level, thickness (0.946) hasthe signicant eect on drying. The pore size and den-sity were also correlated as shown in Figure 10 (a, b)and Table 5. Univariate analysis of variance results alsoindicates that loop length and tightness factor(Figure 10 c,d) have statistically signicant eects onthe WER of the samples at a 95% condence interval.
Contact angle measurement results
Figure 11 shows the contact angle photos and micro-scopic views of the samples. Contact angle values arereported in Table 2. The contact angle which occursbetween the fabric surface and water moleculesdescribes the geometry of solidliquid contact.Contact angles are used for the study of the wettingon a solid material. Interfacial tension can occur onat, homogeneous surfaces by using liquids with dier-ent surface tensions. For heterogeneous structures liketextile fabrics, the contact angle is aected by interfacialtension, surface roughness, chemical heterogeneity,polar groups, sorption layers, suction, porosity, swell-ing, molecular orientation, yarn tension etc.34The con-tact angle also determines the wicking behavior. Alower contact angle causes higher wicking rates.2,7
For our samples, all slack samples have lower contactangle values and higher transfer wicking ratios with lessstiness values compared to tight samples. This result isin attendance with the ndings of Fangueiro et al. andRamachandran et al.21,31
The wetting behavior of a solid surface is controlledby both the surface tension and the roughness of thesurface.35 Textile bers do not have ideal surfaces andtheir wetting phenomena are complicated by surfaceroughness, heterogenity, and adsorption of liquids orsurfactants with a consequent change of surface energy.
Table 5. Correlation coefficients and p-values for water
evaporation rates
Dependent-independent
variables
Pearson
correlation
coefficient p-value
WER-thickness 0.946 0.000WER-pore size 0.793 0.000
WER-density 0.745 0.001WER- loop length 0.616 0.011
WER-Tightness factor 0.513 0.042
Yanlmaz and Kalaoglu 9
at Universiti Tun Hussein Onn Malaysia on April 5, 2015trj.sagepub.comDownloaded from
-
XML Template (2012) [7.2.20123:53pm] [112]{SAGE}TRJ/TRJ 435851.3d (TRJ) [PREPRINTER stage]
Moreover, the geometrical features of fabrics such asthickness and density of fabric, twist, yarn types, yarncount, the internal volume and the pore size distribu-tion make the structure non ideal.32 The fabric con-struction and tightness changes the surface roughnessof the fabric. In order to analyze the eect of the knit-ted structure on the surface tension, contact angle mea-surements are taken. Both fabric construction and
tightness of fabric have an eect on fabric surfaceparameters. As it is seen in Table 2, all tight knittedstructures have higher contact angles than their slackforms due to compactness of the surface. Similar resultswere reported by Truong et al.36 They stated thatreducing the size of the openings between the yarnsby increasing densities makes the fabric tighter. Theincreased tightness makes the fabric more resistant to
Figure 11. Contact angles and microscopic views of the samples.
0.80.70.60.50.40.3
120
110
100
90
80
70
Porosity,%
Con
tact
ang
le,
12010080604020
120
110
100
90
80
70
Density, loops/cm2
Con
tact
ang
le,
0.110.100.090.080.070.060.050.040.030.02
120
110
100
90
80
70
Pore size, cm
Con
tact
ang
le,
Figure 12. The relationship between pore size, density, porosity and contact angle values.
10 Textile Research Journal 0(00)
at Universiti Tun Hussein Onn Malaysia on April 5, 2015trj.sagepub.comDownloaded from
-
XML Template (2012) [7.2.20123:53pm] [112]{SAGE}TRJ/TRJ 435851.3d (TRJ) [PREPRINTER stage]
the hydrostatic pressures that produce surface wetting.Also 2 2 rib fabrics have higher contact angles com-pared to all other samples. Dierent knit types causechanges on fabric roughness due to the fact that knitstructures aect loop density and dimensions of loops.Consequently the highest contact angle values of 2 2rib samples and the higher values of tight samples com-pared to slack samples can be explained by the incre-ment of the roughness of the surface. The roughnessand the contact angle relation may be established bymeasuring the roughness of the knitted fabrics in futurestudies. Furthermore, statistical analysis reveals thatthere is also a signicant correlation between the con-tact angle and the density (coecient 0.527, p-value 0.036), the porosity (coecient0.671,p-value 0.004) and the pore size (coecient0.528,p-value 0.035) as shown in Figure 12.
Conclusions
The statistical analysis results indicate that there is aninverse correlation between pore size and wickingheight. Slack forms of 2 2 rib, 1 1 rib, interlockand single jersey structures have higher transfer wickingratios compared to their tight forms. The statisticalanalysis results also indicate that the WER is inverselyrelated to the fabric thickness. All tight knitted struc-tures have higher contact angles than their slack formsdue to higher compactness of the surface. The testresults revealed that the parameters of comfort are sig-nicantly aected by knitted structure.
Funding
This research received no specic grant from any funding
agency in the public, commercial, or not-for-prot sectors.
References
1. Benltoufa S, Fayala F, Cheikhrouhou M, et al. Porosity
determination of jersey structure. Autex Res J 2007; 7(1):
6369.2. Ogulata RT and Mavruz S. Investigation of porosity and
air permeability values of plain knitted fabrics. Fibres
Textiles East Eur 2010; 18(82): 7175.3. Shahbaz B, Jamil NA, Farooq A, et al. Comparative study
of quality parameters of knitted fabric from airjet and ring
spun yarn. J Appl Sci 2005; 5(2): 277280.4. Kane CD, Patil UJ and Sudhakar P. Studies on the influ-
ence of knit structure and stitch length on ring and com-
pact yarn single jersey fabric properties. Textile Res J
2007; 77(8): 572582.5. Hasan MMB, Calvimontes A, Synytska A, et al. Effects of
topographic structure on wettability of differently woven
fabrics. Textile Res J 2008; 78(11): 9961003.6. Fohr JP, Couton D and Treguier G. Dynamic heat and
water transfer through layered fabrics. Textile Res J 2002;
72(1): 112.
7. Prahsarn C, Barker RL and Gupta BS. Moisture vapor
transport behavior of polyester knit fabrics. Textile Res J
2005; 75(4): 346351.8. Li Y. The science of clothing comfort. Textile progress.
Vol. 31(1/2). The Textile Institute, 2001.9. Hu J, Li Y, Yeung KW, Wong ASW, et al. Moisture
management tester: a method to characterize fabric
liquid moisture management properties. Textile Res J
2005; 75(1): 5762.
10. Supuren G, Oglakcioglu N, Ozdil N, et al. Moisture man-
agement and thermal absorptivity properties of double-
face knitted fabrics. Textile Res J 2011; 81(13):
13201330.11. Bivainyte A and Mikucioniene D. Investigation on the air
and water vapor permeability of double-layered weft
knitted fabrics. Fibres Textiles East Eur 2011; 19(3):
6973.
12. Laing RM, Wilson CA, Gore SE, et al. Determining the
drying time of apparel fabrics. Textile Res J 2007; 77(8):
583590.13. Laing RM, Niven BE, Barker RL, et al. Response of
wool knit apparel fabrics to water vapor and water.
Textile Res J 2007; 77(3): 165171.14. Dent RW. Transient comfort phenomena due to sweat-
ing. Textile Res J 2001; 71(9): 796806.15. Fourt L, Sookne AM, Frishman D, et al. The rate of
drying of fabrics. Textile Res J 1951; 21(1): 2632.16. Yoon HN and Buckley A. Improved comfort polyester.
Part I Transport properties and thermal comfort of poly-
ester cotton blend fabrics. Textile Res J 1984; 54(5):
289298.17. Das B, Das A, Kothari VK, et al. Moisture transmission
through textiles. Part I: Processes involved in moisture
transmission and the factors at play. AUTEX Res J
2007; 7(2): 194216.
18. Yoo S and Barker RL. Moisture management properties
of heat-resistant workwear fabrics Effects of hydro-
philic finishes and hygroscopic fiber blends. Textile
Res J 2004; 74(11): 9951000.19. Troynikov O and Wardiningsih W. Moisture manage-
ment properties of wool polyester and wool bamboo knit-
ted fabrics for the sportswear base layer. Textile Res J
2011; 81(6): 621631.
20. Morent R, Geyter ND, Vansteenkiste CLE, et al.
Measuring the wicking behavior of textiles by the combi-
nation of a horizontal wicking experiment and image pro-
cessing. Rev Sci Instrum 2006; 77: 093502.21. Ramachandran T. A study on influencing factors for
wetting and wicking behaviour. IE (I) J TX 2004; 84:
3741.
22. Blaga M, Marmaral A and Mhai A. High comfort knit-
ted fabrics for linings of orthopaedics footwear. In: The
6th Conference Management of Technological Changes
15 http://www.inventica.org.ro/fibtrico/art1.pdf.23. Wong KK, Tao XM, Yuen CWM, et al. Wicking prop-
erties of linen treated with low temperature plasma.
Textile Res J 2001; 71(1): 49.24. Goclawski J and Urbaniak-Domagala W. The measure-
ment of wetting angle by applying an ADSA model of
Yanlmaz and Kalaoglu 11
at Universiti Tun Hussein Onn Malaysia on April 5, 2015trj.sagepub.comDownloaded from
-
XML Template (2012) [7.2.20123:54pm] [112]{SAGE}TRJ/TRJ 435851.3d (TRJ) [PREPRINTER stage]
sessile drop on selected textile surfaces. Fibres TextilesEast Eur 2008; 16(2): 8488.
25. Oglakcoglu N and Marmarali A. Thermal comfort prop-erties of some knitted structures. Fibres Textiles East Eur2007; 15(56): 6465.
26. Ucar N and Ylmaz T. Thermal properties of 11, 22,33 rib knit fabrics. Fibres Textiles East Eur 2004; 12(3):3438.
27. Ramachandran T, Manonmani G and Vigneswaran C.Thermal behavior of ring and compact spun yarn single
jersey, rib and interlock knitted fabrics. Indian J FibreTextile Res 2010; 35: 250257.
28. Emirhanova N and Kavusturan Y. Effects of knit struc-
ture on the dimensional and physical properties of winterouterwear knitted fabrics. Fibres Textiles East Eur 2008;16(2): 6974.
29. Crow RM and Osczevski RJ. The interaction of waterwith fabrics. Textile Res J 1998; 68(4): 280288.
30. Zhuang Q, Harlock SC and Brook DB. Transfer wickingmechanisms of knitted fabrics used as undergarments for
outdoor activities. Textile Res J 2002; 72(8): 727734.
31. Fangueiro R, Filgueiras A, Soutinho F, et al. Wicking
behavior and drying capability of functional knitted fab-
rics. Textile Res J 2010; 80(15): 15221530.32. Hossain M, Herrmann AS and Hegemann D. Plasma
hydrophilization effect on different textile structures.
Plasma Process Polym 2006; 3: 299307.33. Cil MG, Nergis UB and Candan C. An experimental
study of some comfort-related properties of cotton-
acrylic knitted fabrics. Textile Res J 2009; 79(10):
917923.34. Hossain MM, Hegemann D, Herrmann AS, et al.
Contact angle determination on plasma-treated poly(eth-
ylene terephthalate) fabrics and foils. J Appl Polym Sci
2006; 102: 14521458.35. Ryan BJ and Poduska KM. Roughness effects on contact
angle measurements. Am J Phys 2008; 76(11): 10741077.36. Truong Q and Wilusz E. Designing superoleophobic
chemical/biological (CB) protective clothing, 2010
Nanotechnology for Defense Conference, May 36 2010
Atlanta GA.
12 Textile Research Journal 0(00)
at Universiti Tun Hussein Onn Malaysia on April 5, 2015trj.sagepub.comDownloaded from