Journal of JTEFT

Textile Engineering & Fashion Technology
Research Article
Volume 2 Issue 3 - 2017
Effect of Copper Sulphate on Hydrogen Peroxide Bleaching with Hydrolysis on P/C Fabric Mechanical Properties
Hayavadana J* and Samatha K
Textile Technology, Osmania University, India
Received: February 11, 2017 | Published: July 20, 2017
*Corresponding author: Hayavadana J, Textile Technology, University College of Technology, Osmania University , Hyderabad, India, Email:
Citation: Hayavadana J, Samatha K (2017) Effect of Copper Sulphate on Hydrogen Peroxide Bleaching with Hydrolysis on P/C Fabric Mechanical Properties. J Textile Eng Fashion Technol 2(3): 00060. DOI: 10.15406/jteft.2017.02.00060

Abstract

Surface modification of polyester and Polyester / Cotton material is not a new concept to a processing man. Alkaline oxidation of P/C blends with copper sulphate, hydrogen peroxide and base hydrolysis has shown some interesting trends.                The present work includes the investigation of effect of padding copper sulphate (3 levels) and bleaching with hydrogen peroxide followed by base hydrolysis (2% concentration) at 1:5 and 1:10 MLRs with treatment temperature selected at 110 and 120 degrees centigrade on fabric mechanical properties like tensile strength, bending length, crease recovery and compressibility. In general it is observed that following copper sulphate treatment the weight increases, and decreases after bleaching. Due to the action of caustic, substrate suffers from loss of weight due to removal of chains from surface by NaOH. With increase in bath ratio (w/v) and concentration of copper sulphate, an increase in weight after copper sulphate treatment is observed, followed by decrease in weight after bleaching and loss of weight following hydrolysis. The increase in weight with increase in copper sulphate concentration is mainly due to padding. The results clearly show a positive shift following alkaline oxidation and hydrolysis from gray level. Higher bath ratios with higher hydrolysis temperature have registered a positive shift by about 30%.Decrease in bending length following bleaching and base hydrolysis has indicated the softness of the substrate. At higher bath ratio and hydrolysis temperature, as copper sulphate concentration increases, nearly 20% positive shift is observed in stiffness values. Due to alkaline oxidation and base hydrolysis with higher copper sulphate concentration at higher bath ratio and temperature, nearly 20% negative shift increase recovery values have proved that fabric has become softer following finishing. An excellent compression behavior is observed in bleached, hydrolysed samples. With increase in copper sulphate concentration the compressibility has registered an increasing trend with hydrolysed samples.

Introduction

The popularity of P/C blends at various levels in different fields is the main reason behind the surface modification of P/C blends. In the present day P/C blends are mainly used for dress materials. To modify the surface, oxidation deweighting process experiments were carried out on P/C blended fabric. The cotton fiber is accessible to damage and easy to degrade in certain conditions after being oxidized. The metal ions in the fabric may accelerate the decomposition of hydrogen peroxide and damage the cotton fiber. Among metal ions, copper ranks first in catalyzing such decomposition. On the other hand research studies have confirmed that iron ions may form brown rusty spots on the fabric. If the padded fabric is oxidized by hydrogen peroxide before finishing, the copper ions would drift away from the fabric to the hydrogen peroxide solution, causing effective decomposition of hydrogen peroxide which does not contact the fabric. In oxidation deweighting, the hydrogen peroxide should decompose on the fabric as much as possible and oxidize the cotton fiber. Therefore the fabric is padded with copper sulphate and dried before oxidizing.

Gao Ming & Dong Ying [2] has studied alkaline oxidation of P/C blended poplin fabric. In their study the relation between deweighting ratio with copper sulphate and hydrogen peroxide is reported. Process parameters like bath ratio, treatment times and concentration of NaOH on deweighting ratio are also reported. Although a considerable work has been reported on the effect of alkaline oxidation on deweighting ratio of P/C blends, work on the effect of alkaline oxidation followed by base hydrolysis on fabric mechanical properties like tensile strength, bending length etc. is scanty in literature. Hence the thrust of the present investigation is to investigate the effect of alkaline oxidation followed by base hydrolysis for a suiting fabric on mechanical properties.

Materials and Methods

Materials

The geometrical parameters of 67/33 P/C suiting fabric are as follows Ends/inch=68, picks/inch=58, count of warp and weft=2/40s T/C×2/40s T/C. The fabric was woven on ruti-c loom with 59.5” reed space. The chemicals used were of laboratory grade and were not purified further.

Methods

Copper, sulphate padding with 10%, 20% and 30% was carried out in sealed beakers at room temperature using laboratory model HTHP beaker dyeing machine and dried in oven Zeronian [1]. The pad-dried fabric samples were then bleached using hydrogen peroxide (30% volume) at 60-80 degrees temperature. The procedure followed was recommended by Gao Ming & Dong Ying [2]. The bleached samples were then base hydrolysed using 2% NaOH with 1:5 and 1:10 bath ratios (w/v) at 110 and 120 degrees for 30 minutes. The purpose of using low liquor ration is on the concept of low liquor dyeing using HTHP machine. Table 1 shows the coding of fabric samples with roman II for bleached samples and roman I for hydrolysed samples, indicated throughout the experiment. The samples were washed with tap water to remove excess alkali, followed by neutralization with 0.5% acetic acid and finally washed in deionised water and dried in oven.

Code

Copper Sulphate Concentration

NaOH Concentration

Liquor Ratio

Temperature (for Hydrolysis)

10 C1

10%

2%

1:05

110 Degrees

20 C1

20%

2%

1:05

110 Degrees

30C1

30%

2%

1:05

110 Degrees

10C2

10%

2%

1:05

120 Degrees

20C2

20%

2%

1:05

120 Degrees

30C2

30%

2%

1:05

120 Degrees

10C3

10%

2%

1:10

110 Degrees

20C3

20%

2%

1:10

110 Degrees

30C3

30%

2%

1:10

110 Degrees

10C4

10%

2%

1:10

120 Degrees

20C4

20%

2%

1:10

120 Degrees

30C4

30%

2%

1:10

120 Degrees

Table 1: Sample coding.

Conditioning and testing

The finished samples were conditioned at standard atmospheric conditions RH 65+-2% and temperature 27+-2 degrees as per IS 6359-1971.

Determination of geometrical properties

Measurement of yarn linear density: Yarn count was determined as per IS1315 and an average of 10 measurements is reported.

Measurement of yarn crimp

The crimp of yarns unravelled from the test fabric was measured on Shirley crimp as per IS: 3442-1966. Measurements were taken in both warp and weft ways. The average was given in percentage using following formula.

% Crimp = ( L 2   L 1 /  L 1 )*100 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVCI8FfYJH8YrFfeuY=Hhbbf9v8qqaqFr0xc9pk0xbb a9q8WqFfeaY=biLkVcLq=JHqpepeea0=as0Fb9pgeaYRXxe9vr0=vr 0=vqpWqaaeaabiGaciaacaqabeaadaqaaqaaaOqaaKqzGeaeaaaaaa aaa8qacaGGLaGaaeiiaiaadoeacaWGYbGaamyAaiaad2gacaWGWbGa aeiiaiabg2da9iaabccajuaGpaWaaeWaaOqaaKqzGeWdbiaadYeaju aGpaWaaSbaaSqaaKqzadWdbiaaikdaaSWdaeqaaKqzGeWdbiaacobi caqGGaGaamitaSWdamaaBaaabaqcLbmapeGaaGymaaWcpaqabaqcLb sapeGaai4laiaabccacaWGmbWcpaWaaSbaaeaajugWa8qacaaIXaaa l8aabeaaaOGaayjkaiaawMcaaKqzGeWdbiaacQcacaaIXaGaaGimai aaicdaaaa@52F5@  (1)

Where L1=length of yarn in the fabric, L2= stretched length of the yarn.

Determination of fabric GSM

GSM of the fabric samples was measured as per IS: 1964-1970.Fabric GSM was determined and the value reported is an average of measurements.

Determination of fabric thickness (Compressibility)

Fabric thickness was measured using Shirley thickness gauge as per the standard test method IS: 7702-1975. The result shown is an average of at least 10 random measurements. EMC of control and treated fabric samples are was determined using in Table 2:

EMC( % )=( T o T m )/ T o ×100 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVCI8FfYJH8YrFfeuY=Hhbbf9v8qqaqFr0xc9pk0xbb a9q8WqFfeaY=biLkVcLq=JHqpepeea0=as0Fb9pgeaYRXxe9vr0=vr 0=vqpWqaaeaabiGaciaacaqabeaadaqaaqaaaOqaaKqzGeaeaaaaaa aaa8qacaWGfbGaamytaiaadoeajuaGpaWaaeWaaOqaaKqzGeWdbiaa cwcaaOWdaiaawIcacaGLPaaajugib8qacqGH9aqpjuaGpaWaaeWaaO qaaKqzGeWdbiaadsfalmaaBaaabaqcLbmacaWGVbaaleqaaKqzGeGa ai4eGiaadsfajuaGdaWgaaWcbaqcLbmacaWGTbaaleqaaaGcpaGaay jkaiaawMcaaKqzGeWdbiaac+cacaWGubqcfa4damaaBaaaleaajugW a8qacaWGVbaal8aabeaajugib8qacqGHxdaTcaaIXaGaaGimaiaaic daaaa@5377@  (2)

To =Thickness at 0.5 gf / cm2 Tm =Thickness at maximum load

Sample

50 g

100g

150g

200g

250g

300g

Control

4

6

8

11

12

14

10C1 II

4.3

6.8

10.34

11.2

12.06

12.93

20C1 II

3.27

4.9

8.19

9.8

10.65

11.47

30C1 II

1.6

5.6

6.45

8.8

9.6

11.29

10C2 II

3.38

5.08

9.32

10.16

11.86

12.71

20C2 II

1.66

4.16

5.83

7.5

10.83

12.5

30C2 II

1.61

4.83

7.25

8.87

11.29

12.9

10C3 II

3.33

5.83

7.5

9.16

10.83

12.5

20C3 II

2.27

4.54

6.63

8.18

9.09

10.9

30C3 II

3.5

5.26

7.01

8.77

10.52

11.4

10C4 II

4.16

5.8

8.3

10.83

15

16.66

20C4 II

1.78

4.46

8.92

10.71

12.5

14.28

30C4 II

3.33

5

6.66

8.33

9.16

12.5

Hydrolysed Samples

3

4

7

9

12

13

10C1 I

2.04

5.01

7.14

9.18

11.22

12.24

20C1 I

1.74

4.31

6.03

7.75

9.48

12.06

30C1 I

2.67

4.46

7.14

8.9

11.6

13.39

10C2 I

1.78

7.14

9.82

8.95

14.28

16.07

20C2 I

1.75

3.5

6.14

7.89

10.52

12.28

30C2 I

2.7

4.6

6.48

9.25

11.11

12.96

10C3 I

1.78

4.46

6.25

8.03

9.82

11.6

20C3 I

1.85

3.7

6.48

8.33

11.11

12.03

30C3 I

1.92

3.8

6.7

8.6

11.53

13.46

10C4 I

1.96

3.9

5.8

7.8

9.8

10.78

20C4 I

2.8

5.6

7.5

9.43

10.37

11.32

Table 2: Effect on Compressibility.

Determination of fabric set

Fabric set of the samples was determined as per IS: 1963-1969. This parameter defined the average distance between two consecutive threads in a fabric. Ends per inch and picks per inch are measured using Densimeter. The average of 10 observations selected randomly is reported as the final value which is later converted to threads per inch and was expressed in inches.

Testing of mechanical properties

Measurement of fabric tensile strength: Tensile strength of control and finished samples were measured as per IS1969-1968 using universal testing machine. Table 3 shows the tensile strength of control, bleached and hydrolysed samples.

Sample

Warp Way

Weft Way

Strength

% Shift

Strength

% Shift

Control

45.75

-

44

-

10C1 II

44

3.8

42

0.54

20C1 II

43

6.01

41

6.81

30C1 II

40

12.56

39

11.36

10C2 II

43

6.01

42

4.54

20C2 II

37

19.12

37.2

15.45

30C2 II

44

3.8

43

2.27

10C3 II

43

6.01

40

9.09

20C3 II

42

8.19

41

6.81

30C3 II

38

16.93

37

15.9

10C4 II

41

10.38

38

13.63

20C4 II

38

16.93

36

18.18

30C4 II

40

12.56

37

Hydrolysed Samples

10C1 I

41

10.38

40

9.09

20C1 I

40

12.56

37

15.09

30C1 I

36.4

20.43

40

9.09

10C2 I

-

-

-

-

20C2 I

-

-

-

-

30C2 I

36

21.31

29.6

29.52

10C3 I

35.4

22.62

35

16.66

20C3 I

38

16.93

40

4.76

30C3 I

-

-

-

-

10C4 I

38

16.93

36

14.28

20C4 I

36

21.31

34

19.04

Table 3: Effect on Tensile Strength.

Measurement of bending length: Shirley stiffness tester working on cantilever principle was used and the average of 10 replications is reported in Table 4 for control, beached and hydrolysed samples warp and weft way. The procedure followed is as per IS6490-1971.

Sample

Warp Way

Weft Way

Bending Length (cm)

% Shift

Bending Length (cm)

% Shift

Control

1.7

-

1.6

-

10C1 II

1.51

11.17

1.38

13.75

20C1 II

1.61

5.29

1.55

3.12

30C1 II

1.66

2.35

1.36

15

10C2 II

1.5

11.76

1.53

4.37

20C2 II

1.51

11.17

1.36

15

30C2 II

1.61

5.29

1.36

15

10C3 II

1.55

8.82

1.46

8.75

20C3 II

1.5

11.76

1.36

15

30C3 II

1.51

11.17

1.41

11.87

10C4 II

1.61

5.29

1.48

7.5

20C4 II

1.43

15.88

1.36

15

30C4 II

1.52

10.58

1.45

9.3

Hydrolysed Samples

10C1 II

1.3

23.52

1.26

21.25

20C1 II

1.45

14.7

1.46

8.75

30C1 II

1.5

11.76

1.36

15

10C2 II

1.35

20.58

1.28

20

20C2 II

1.38

18.82

1.3

18.75

30C2 II

1.41

17.05

1.35

15.62

10C3 II

1.35

20.58

1.28

20

20C3 II

1.43

15.88

1.34

16.25

30C3 II

1.46

14.11

1.36

15

10C4 II

1.41

17.05

1.35

15.62

20C4 II

1.41

17.05

1.3

18.75

Table 4: Effect on bending length.

Measurement of crease recovery: Shirley crease recovery tester was used to measure crease recovery angle of control bleached and finished angles as per IS4681-1968. The results reported as the average of 5 observations are shown in Table 5.

Sample

Warp Way

Weft Way

Crease Recovery (Angle)

% Shift

Crease Recovery (Angle)

% Shift

Control

99.5

-

115

-

10C1 II

109.5

10.05

126.5

12

20C1 II

110

10.5

127

12.88

30C1 II

113.5

14.07

128.5

13.77

10C2 II

115.25

15.82

129.5

15.11

20C2 II

117.5

18.09

131.75

17.11

30C2 II

114.5

15.07

125

11.11

10C3 II

112.5

13.06

124

10.22

20C3 II

112

12.56

119.5

6.2

30C3 II

111

11.55

122

8.4

10C4 II

111.5

12.06

123

9.3

20C4 II

119

19.59

126

12

30C4 II

108

8.54

119

5.7

Hydrolysed Samples

10C1 II

111.5

12.06

128

13.77

20C1 II

113

13.56

129.5

15.11

30C1 II

118

18.59

132

17.33

10C2 II

116

16.58

129

14.66

20C2 II

119.5

20.1

131.5

16.88

30C2 II

122.5

23.11

133.5

18.66

10C3 II

120.5

21.1

131.5

16.88

20C3 II

124

24.62

134

19.11

30C3 II

125

25.62

135.5

20

10C4 II

121

21.6

132

17.33

20C4 II

120

20.6

131

16.44

Table 5: Effect on Crease Recovery.

Results and Discussion

Effect on weight following each chemical treatment

Table 6a shows the increase in weight after copper sulphate treatment and decrease in weight after bleaching and hydrolysis. It is clear that with the increase in copper sulphate concentration the increase in weight is due to padding. On the other hand the increase in weight loss after bleaching, as the copper sulphate concentration is increased, may be due to the removal impurities and the action of hydrogen peroxide on cotton. Similarly the weight loss after hydrolysis is due to the action of caustic on polyester. A height weight loss of 9% is observed with 30% copper sulphate concentration at 120 degrees temperature. Table 6b high lights the % shift in the weight following each chemical treatment at 1:5 and 1:10 bath ratios. The % shift (positive and negative) in weight increases with increase in copper sulphate concentration. Trend is similar for bleached and hydrolysed samples. This may be due to the facts as explained above. The results are in concomitant with several researcher investigations.

Sample

% Increase in Weight After Copper Sulphate Treatment

% Decrease in Weight After Bleaching

% Decrease in Weight After Hydrolysis

10C1 I

5.4

5.4

6.2

10C1 II

5.09

5.13

-

20C1 I

8.4

6.34

6.3

20C1 II

6.2

5.01

-

30C1 I

8.6

6.66

5.52

30C1 II

9.07

7.02

-

10C2 I

4.8

4.9

7.5

10C2 II

4.6

3.9

-

20C2 I

5.7

4.8

7.1

20C2 II

5.6

4.3

-

30C2 I

5.8

3.8

8.4

30C2 II

5.4

3.66

-

10C3 I

6.2

6.2

5.64

10C3 II

4.08

4.3

-

20C3 I

9.7

8.3

5.22

20C3 II

9.7

8.7

-

30C3 I

11.07

9.1

6.57

30C3 II

12.97

10.95

-

10C4 I

15.3

13.28

9.05

10C4 II

7.1

5.8

-

20C4 I

12.8

7.6

9.93

20C4 II

6.7

6.5

-

30C4 I

14.05

7.8

9.07

30C4 II

14.36

7.5

-

Table 6a: Weight loss of samples after each chemical treatment.

Copper Sulphate Concentration

Average Increase in Weight After Copper Sulphate Treatment

Average Decrease in Weight After Bleaching

Average Decrease in Weight After Hydrolysis at Temperature

110 Degrees

120 Degrees

For 1:5 Bath Ratio:

10%

4.89

4.83

6.2

7.5

20%

6.47

5.11

5.52

8.4

30%

7.21

5.28

5.52

8.4

For 1:10 Bath Ratio:

10%

8.17

7.39

6.3

7.1

20%

9.725

7.75

5.22

9.93

30%

13.112

8.83

6.57

9.07

Table 6b: Effect of Chemical treatment.

Effect on tensile strength

From the literature scan, it is observed that following base hydrolysis the fabric loses 5-10% fabric strength. Table 7a & 7b addresses the positive shift for bleached and hydrolysed samples at 1:5 and 1:10 bath ratios with 3 levels of copper sulphate concentration. It is clear from the table that % shift increases in all cases with increase in copper sulphate concentration. This is due to loss in tensile strength following bleaching and hydrolysis. Reduction in tensile strength of bleached and hydrolysed samples may be due to gradual removal of molecular chains from the structure. The results are in agreement with findings by Zeronian & Collin [1].

Copper Sulphate Concentration

Warp Way Shift

Weft Way Shift

For 1:5 Bath Ratio:

10%

4.905

4.54

20%

12.56

11.17

30%

8.17

6.81

For 1:10 Bath Ratio:

10%

8.195

11.36

20%

12.56

12.49

30%

14.74

15.9

Table 7a: Average % Shift for tensile strength of bleached samples.

Copper Sulphate Concentration

Warp Way Shift

Weft Way Shift

110 Degrees

120 Degrees

110 Degrees

120 Degrees

For 1:5 Bath Ratio:

10%

10.38

-

9.09

-

20%

12.56

-

15.9

-

30%

20.43

21.31

9.09

29.52

For 1:10 Bath Ratio:

10%

22.62

16.93

16.66

14.28

20%

16.93

21.31

15.9

19.04

30%

-

21.31

-

30

Table 7b: Average % shift for tensile strength of hydrolysed samples-Effect of Temperature.

Effect on warp and weft way bending length

The positive % shift in bending length values of warp weft at 1:5 and 1:10 bath ratios with increase in copper sulphate concentration for bleached and hydrolysed (110 and 120 degrees temperature) samples is reported in Table 8a & 8b. A general trend observed is that % shift reduces with increase in copper sulphate concentration for warp but follows an irregular pattern for weft. The shift in bending length may be due to loss of weight following base hydrolysis. The fall in bending length values has clearly shown that fabric has imparted soft feeling.

Copper Sulphate Concentration

Warp Way Shift

Weft Way Shift

For 1:5 Bath Ratio:

10%

11.465

9.06

20%

8.23

9.06

30%

3.82

15

For 1:10 Bath Ratio:

10%

7.05

8.125

20%

13.82

15

30%

10.87

10.58

Table 8a: Average % Shift for bending strength of bleached samples.

Copper Sulphate Concentration

Warp Way Shift

Weft Way Shift

110 Degrees

120 Degrees

110 Degrees

120 Degrees

For 1:5 Bath Ratio:

10%

23.52

20.58

21.25

20

20%

14.7

18.82

8.75

18.75

30%

11.76

17.05

15

15.62

For 1:10 Bath Ratio:

10%

20.58

17.05

20

15.62

20%

15.88

17.05

16.25

18.75

30%

14.11

11.76

15

21.87

Table 8b: Average % shift for bending length of hydrolysed samples (Temperature).

Effect on crease recovery

Table 9a & 9b shows the average % shift (negative) increase recovery angle for bleached and hydrolysed samples in different conditions. With the increase in copper sulphate concentration and treatment temperature, the hydrolysed samples have shown larger crease recovery angles. This may be due to the fact that following weight loss, the fabric has become soft.

Copper Sulphate Concentration

Warp Way Shift

Weft Way Shift

For 1:5 Bath Ratio:

10%

12.935

13.55

20%

14.29

14.99

30%

14.57

12.44

For 1:10 Bath Ratio:

10%

12.56

9.77

20%

16.075

9.11

30%

10.045

7.1

Table 9a: Average % Shift for crease recovery of bleached samples.

Copper Sulphate Concentration

Warp Way Shift

Weft Way Shift

110 Degrees

120 Degrees

110 Degrees

120 Degrees

For 1:5 Bath Ratio:

10%

12.06

16.58

13.77

14.66

20%

13.56

20.1

15.11

16.88

30%

8.59

23.11

17.33

18.66

For 1:10 Bath Ratio:

10%

21.1

21.6

16.88

17.33

20%

24.62

20.6

19.11

16.44

30%

25.62

25.62

20

19.11

Table 9b: Average % shift for crease recovery of hydrolysed samples (Temperature).

Effect on compressibility

Table 2 reports the EMC values for bleached and hydrolysed samples. It is observed that with increase in copper sulphate concentration, compressibility decreases for bleached samples. A reverse trend is observed in the case of hydrolysed samples.

Conclusion

It is clear from the above discussions that P/C blended fabrics can be imparted a soft silk like feeling following weight reduction by alkaline oxidation and base hydrolysis and the fabric will exhibit the following features.

  1. The fabric is very sensitive to chemical processing like effect of Copper sulpahate, Bleaching and alkaline hydrolysis.
  2. Improved Compressibility following finishing.
  3. Higher crease recovery and lower bending length.
  4. Acceptable strength loss.

References

  1. Zeronian SH, Collins MJ (1989) Surface modification of polyester by alkaline treatments. Textile Progress 20(2): 1-26.
  2. Gao Ming, Dong Ying (1996) Treating fabric through alkaline oxidation for a silk-like effect. American Dyst Rep p. 10-26.
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