C ellulase enzymes treatments are known to be effective in improving the physical properties of cotton

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1 2012 by ARAHE Journal of ARAHE, Vol. 19, 2012 Optimization of the Pre-treatment Process with Neutral Cellulase Enzyme to Improve Physical Properties of Handloom Cotton Fabric Sunita Dixit, Shahnaz Jahan 1 Department of Clothing & Textiles, Faculty of Home Science, Kamla Nehru Institute of Physical & Social Sciences, Sultanpur, India 1 Department of Clothing & Textiles, College of Home Science, G.B. Pant University of Agriculture & Technology, Pantnagar ABSTRACT C ellulase enzymes treatments are known to be effective in improving the physical properties of cotton fabric. Nowadays handloom cotton has become popular due to their wearing comfort, but they need finishing to improve their appearance and physical properties. Therefore, in the present study an attempt has been made to optimize conditions i.e. concentration, treatment time and temperature for the use of neutral cellulase enzyme and evaluate the changes in physical properties like weight loss, moisture absorption, strength loss, bending length and crease recovery angle of the handloom cotton fabric. The optimum condition of the experiment obtained was 2.0% (owf) concentration, 70 minutes treatment time and 70 C temperature. (J ARAHE 19:49-54, 2012) KEY WORDS: Bending length, crease recovery angle, moisture absorption, neutral cellulase, strength loss. INTRODUCTION Address for correspondence: Sunita Dixit, Department of Clothing & Textiles, Faculty of Home Science, Kamla Nehru Institute of Physical & Social Sciences, Sultanpur, India Tel: dixit.sunita30@gmail.com Today the use of enzymes in textile processing is well established industrial technology. Enzymes being biological molecules and efficient catalysts provides environmentally acceptable routes to replace harsh chemicals. Cellulase enzymes are highly effective in removing loose fibres from fabric surface, a process known as biopolishing (Etters, Lange, & Husain, 1999). Handloom cotton has some shortcomings, like higher maintenance costs for washing and ironing. It is also less preferred due to rough texture and low drapeabilty. The annual reports of handloom and handloom sector presents a sorrowful picture of piling up of stocks in godowns (Sarvani & Balakrishnaiah, 2007). The cellulolytic system of cellulase is composed of two exo-cellobiohydrolases, at least six multiple endoglucanases and two β-glucosidases. Exo-cellulases act on cellulose polymer chain ends and produce primarily cellobiose. Endo-cellulases act randomly along the cellulose polymer chains breaking very long polymers into shorter chains. β- glucosidases act on short, soluble oligosaccharides to produce primarily glucose (Karmakar, 1998). The careful control of enzyme treatment process variables such as, concentration, treatment time and temperature are important for optimizing the cellulase enzyme activity for the enhancement of the product. Therefore, in the present study an attempt has been made to optimize conditions for the use of neutral cellulase enzyme and evaluate the changes in physical properties like weight loss, moisture absorption, strength loss, bending length and crease recovery angle. Fabric EXPERIMENTAL Pure white handloom cotton fabric was procured from

2 50 / J ARAHE 19 : 49-54, 2012 Gandhi Ashram of local market in Pantnagar (Uttarakhand). Enzymatic treatment The enzyme treatment was carried out in Metrex launderometer and consisted of: Commercial neutral cellulase enzyme (Americos Cellucom 110 OM)(from Americos Industries, Ahmedabad). Weight loss To study the weight loss due to pretreatment, weight of the fabric samples before and after the treatment was taken. These fabric samples were conditioned for 24 hours at room temperature using saturated common salt solution in a dessicator and then weighed. Each sample was weighed separately. These were dried and conditioned for 24 hours in a dessicator and again weighed after the enzyme treatment also. The percentage weight loss was calculated using the following formula: Weight loss (%)= Where, W1=Weight of the fabric before enzyme treatment W2=Weight of the fabric after enzyme treatment Moisture content (%) (W1-W2) 100 W1 The moisture content of cotton fabric was determined using IS: test method. Five test specimens, each weighing approximately 3 g+0.2 g were drawn from the sample. The specimen was weighed accurately in a dry and cleaned petridish. The petridish containing the test specimen was placed in the drying oven and specimen was dried at 105 to 110 to constant mass. The oven dry mass of the test specimen was determined. Similarly other test specimens were tested. The percentage of moisture content in the test specimen was calculated by the following formula: Moisture, percent by mass= Where, (a-b) 100 a a=original mass, in g, of the test specimen; and b=oven dry mass in g, of the test specimen Moisture content of the fabric was calculated by taking the mean of five measurements. Strength loss Raveled strip test method was used. The tensile strength was measured on the KMI electronic tensile strength tester. Strength loss (%) was calculated from the formula: Strength loss (%)= Where, S1=breaking strength before treatment S2=breaking strength after treatment Bending length The bending length of the cotton fabric was determined on Eureka Cloth stiffness tester using IS: test method. Samples of size mm were cut from both warp way and weft way direction with the help of a template from different position of the sample under test. Crease recovery angle The crease recovery angle of the cotton fabric was determined by IS: test method. Warp way and weft way test specimens of mm size were tested. Water absorption S 1-S S 1 The static immersion test (BS 3449) is a method for measuring the total amount of water that a fabric will absorb. Sufficient time is allowed in the test for the fabric to reach its equilibrium absorption.in the test weighed samples of the cotton fabric were immersed in water for a given length of time, taken out and the excess water was removed by shaking. They were then weighed again and the weight of water absorbed was calculated as a percentage of the dry weight of the fabric. Five specimens each mm were cut at 45 to the warp direction. The first step was to condition the samples and weigh them. They were then immersed in distilled water at a temperature of 20±1 to a depth of 10 cm. A wire sinker was used to hold the specimen at the required depth. The samples were left in that position for 20 minutes. After removing the specimen from sinker they

3 Dixit & Jahan : Optimization of the Pre-treatment Process / 51 were shaken 10 times in a mechanical shaker. They were then transferred directly to preweighed airtight containers and then reweighed. Absorption was calculated by following formula: Absorption= Five readings were recorded and mean percentage absorption was calculated. RESULTS AND DISCUSSION Effect of concentration Mass of water absorbed Originalmass 100% The handloom cotton samples were treated with varying concentrations of neutral cellulase i.e. 0.5, 1.0, 1.5, 2.0 and 2.5% owf at optimum ph 7.5. Enzymatic treatment was carried out in Launderometer at 45±2 for 45 minutes. Table 1 reveals that on increasing the concentration of neutral cellulase enzyme from 0.5 to 2% (owf), significant increase in the physical parameters such as weight loss, moisture content, bending length (both in warp and weft direction), strength loss (both in warp and weft direction), crease recovery angle (both in warp and weft direction), thickness and water absorption resulted, but on increasing the concentration beyond 2.0% (owf) i.e. at 2.5% (owf), slight or negligible improvement in the physical properties was observed.the significant weight loss (3.79%) and moisture content (4.19%) were observed at 2.0% (owf). The significant reduction in bending length in both warp ( cm) and weft ( cm) direction was observed on increasing the concentration from 0.5 to 2.0%. Fabric strength loss is a function of the degree of enzyme hydrolysis and the level of mechanical action. However, minimum percentage strength loss in both warp ( %) and weft ( %) occurred with an increase in concentration from %.The crease recovery angle in warp direction was 85 at 0.5% concentration, while it was increased to 122 on increasing concentration to 2.0%. In case of weft direction, the crease recovery angle was 96 at concentration 0.5% and increased to 130 at 2.0% concentration. Afterwards with increase in concentration, negligible increase in crease recovery angle in both warp and weft direction was observed. It was also observed that there was significant reduction in fabric thickness 2.0%, it was reduced from 0.52 mm to 0.38 mm.the maximum significant water absorption i.e % was measured at 2.0%. These results are in agreement with the results obtained by Ibrahim et al. (2000). These results showed that treatment with 2% enzyme brought about a loss in weight and tensile strength, along with a decrease in thickness and stiffness of the biotreated sample attributes to the enzymatic hydrolysis of cellulase especially in the amorphous regions. The F-values [Table 1], as obtained from one way analysis of variance at 1% level of significance was found to be statistically significant due to different concentration levels. It was also confirmed statistically by comparison of means that the significant difference in the mean values of all the physical parameters occurred up to 2.0% concentration, af- Table 1. Mean value, standard deviation and F-value of physical tests at different concentration of neutral cellulase enzyme on handloom cotton fabric Physical parameters Concentrations 0.5% (owf) 1.0% (owf) 1.5% (owf) 2.0% (owf)* 2.5% (owf) M SD M SD M SD M SD M SD F value Weight loss (%) ** Moisture content (%) ** Bending length warp (cm) ** Bending length weft (cm) ** Strength loss warp (%) ** Strength loss weft (%) ** Crease recovery angle warp ( ) Crease recovery angle weft ( ) ** ** Thickness (mm) ** Water absorption (%) ** * : Selected concentration, **: 1% level of significance

4 52 / J ARAHE 19 : 49-54, 2012 ter which no significant difference was found due to increase in concentration level. Thus, considering all the physical parameters studied, 2.0% (owf) concentration was selected as optimum for further study. Effect of treatment time Optimization of treatment time for treatment of handloom cotton with neutral cellulase was carried out for five different intervals i.e. 30, 40, 50, 60 and 70 minutes at optimum ph 7.5 and concentration 2.0% (owf). Enzymatic treatment was carried out in Launderometer at 45±2. It is evident from the Table 2 that with an increase in treatment time from 30 to 70 minutes, a significant increase in weight loss ( %) and moisture content ( %) was found. Tyndall and Raleigh (1991) have indicated that depending on the treatment time, a certain weight loss and strength loss is to be expected after the enzyme treatment. Hartzell-Lawson and Durrant (2000) also observed the increase in moisture absorbency on cotton with increase in reaction time. The decrease in bending length in both warp and weft direction ranged from 1.24 to 0.94 cm and 1.19 to 0.84 cm respectively was found with an increase in the treatment time from 30 to 70 minutes.similarly negligible percentage strength loss in both warp ( %) and weft ( %) direction was observed with an increase in the treatment time. It was found that as the treatment time was increased, the crease recovery angle in both warp and weft direction was also increased. It was 87, 93, 123, 133 and 138 in warp direction and 94, 105, 131, 135 and 139 in weft direction at 30, 40, 50, 60 and 70 minutes. The reduction in fabric thickness from 0.49 to 0.34 mm was also observed with increase in treatment time from 30 to 70 minutes.the water absorption was 47.06, 61.79, 72.52, and 80.46% at 30, 40, 50, 60 and 70 minutes, respectively. The F-values, computed at 1% level of significance from one way analysis of variance as indicated in table 2 showed that there was significant difference in the physical parameters related to different treatment time. It was also found statistically by comparison of means that significant difference in the mean values of physical parameters occurred among five different treatment time. Therefore keeping in view all the physical parameters studied, 70 minutes of neutral cellulase enzymatic treatment was considered as optimum for the further study. Effect of temperature The handloom cotton samples were treated with different temperature levels of neutral cellulase i.e. 50, 55, 60, 65 and 70 C with optimum ph 7.5, concentration 2.0% (owf) and treatment time 70 minutes. The results presented in table 3 regarding various temperature levels indicated that neutral cellulase enzyme treatment had minimum effect on the weight loss and tensile strength loss, even at the highest temperature level of enzymatic treatment. According to Shukla et al. (2000) the extent of the treatment can be easily evaluated by means of weight loss, which must be around 3-5%. As a result, fabric become smooth with the loss of loose fibres and the hand becomes Table 2. Mean value, standard deviation and F-value of physical tests at different treatment time of neutral cellulase enzyme on handloom cotton fabric Physical parameters Treatment time 30 min 40 min 50 min 60 min 70 min* M SD M SD M SD M SD M SD F value Weight loss (%) ** Moisture content (%) ** Bending length warp (cm) ** Bending length weft (cm) ** Strength loss warp (%) ** Strength loss weft (%) ** Crease recovery angle warp ( ) ** Crease recovery angle weft ( ) ** Thickness (mm) ** Water absorption (%) ** * : Selected treatment time, **: 1% level of significance

5 Dixit & Jahan : Optimization of the Pre-treatment Process / 53 soft and there is also a loss in fabric strength, proportional to the amount of weight reduction. Significant increase in moisture content of the handloom cotton fabric i.e. from 4.26 to 5.19% was observed on increasing the temperature of neutral cellulase enzyme from 50 to 70 C.The bending length in warp direction was decreased from 0.91 to 0.71 cm and in weft direction it ranged from 0.86 to 0.69 cm with an increase in temperature from C.The data presented in the table revealed that negligible percentage strength loss in both warp ( %) and weft ( %) direction was observed an increasing temperature ranging from C. It was found that with an increase in temperature, the significant increase in crease recovery angle in both warp ( ) and weft ( ) direction was obtained. The improvement in crease recovery angle on cellulase enzyme treatment of polyester viscose fabrics has already been reported by Sharma et al. (1998).It was also observed that the thickness reduction ranged from 0.50 to 0.34 mm with an increase in temperature. At 50, the water absorption was 80.81% while it increased to 89.99% at 70 C temperature. The F-values [Table 3], as obtained from one way analysis of variance was found to be significant at 1% level of significance. Hence it was concluded that there was significant difference in the physical parameters due to different temperatures. Significant differences in the mean values of physical parameters were observed among five different temperatures by comparison of means at 1% level of significance. Thus, on the basis of all the above physical parameters studied with an increase in temperature, 70 C temperature for neutral cellulase enzyme was considered as optimum for further study. CONCLUSIONS Cellulase enzymes are important tools in the textile industry for processing cellulose fibres. They provide an economical and ecological way to treat cotton fabrics. Thus, it was concluded from the present study that the positive effects obtained with neutral cellulase enzymes i.e., moisture absorption, bending length and crease recovery angle were maximized by using the optimized enzymatic process variables. The optimum condition of the experiment obtained was 2.0% (owf) concentration, 70 minutes treatment time and 70 C temperature. Nowadays, the use of cellulases in the pretreatment process has found much broader acceptance as the effect of the treatment is long lasting. The colour of the dyed fabric also became brighter with more colour yield. The enzymatic pretreatment of the textiles are not aggressive to fibres and environment. The information generated from the study is very useful for the agriculturists, cotton manufacturers, khadi industry, textile finishers and consumers. The textile finishers can safely apply these finishes to handloom cotton to improve physical properties without altering their mechanical properties. REFERENCES Etters, J. N., Lange N. K., & Husain, P. A. (1999). Scouring the matrix. Available online at Com/ News.htm?CD=404&ID=1809. Table 3. Mean value, standard deviation and F-value of physical tests at different temperature of neutral cellulase enzyme on handloom cotton fabric Physical parameters Temperature 50 C 55 C 60 C 65 C 70 C* M SD M SD M SD M SD M SD F value Weight loss (%) ** Moisture content (%) ** Bending length warp (cm) ** Bending length weft (cm) ** Strength loss warp (%) ** Strength loss weft (%) ** Crease recovery angle warp ( ) ** Crease recovery angle weft ( ) ** Thickness (mm) ** Water absorption (%) ** * : Selected temperature, **: 1% level of significance

6 54 / J ARAHE 19 : 49-54, 2012 Hartzell-Lawson, M., & Durrant, S. K. (2000). The efficiency of pectinase scouring with agitation to improve cotton fabric wettability. Textile Chemist and Colourist and American Dyestuff Reports, 32(8), Ibrahim, N. A., Allam, E., Morsy, M. S., El-Zairy, M. R., & Hassan, T. M. (2000). Bio-finishing of pre dyed cotton fabrics. Colourage, 67(4), Karmakar, S. R. (1999). Application of biotechnology in the pretreatment processes of textiles. Colourage Annual, Sarvani, V., & Balakrishnaiah, B. (2007). Wrinkle recovery, treatment to khadi and handloom fabrics. The Indian Journal, 117(7), Sharma, I. C., Chattopadhyay, D. P., Chatterjee, K. N., Mukhopadhyay, A., & Kumar, A. (1998). Improvement in jute fabric handle through biofinishing. Indian Journal of Fibre Textile Research, (23), 44. Shukla, S. R., Sharma, U., & Kulkarni, K. S. (2000). Enzymes and their use in textile processes. Colourage, 67(2), Tyndall, R. M., & Raleigh, N. C. (1991). AATCC Book of Papers, pp. 269.