Chapter 3 (3)doc

3.8 LB Isotherms All the π-A isotherms indicate that the amphiphile with Schiff’s base moiety as head group can form a fairly stable monolayer at the air/water interface. Figure 3.46 (a) (b) (c) shows the surface pressure – molecular area (π-A) and surface potential- area (ΔV-A) isotherms of 1A, 2A and 3A respectively. Compounds 1A and 2A show clear liquid expanded (LE) to liquid condensed (LC) states while 3A shows only a liquid expanded state. This is unexpected because compound 3A has the same rigid polar head group as 1A, with only the alkyl chain longer by two carbons. It is likely that the longer chains prevent closer packing in the molecules at airwater interface, thereby leading to a more expanded Langmuir film. The corresponding ΔV- A isotherms also show similar trends. From these isotherms, using the Helmholtz equation (3.1), the normal component to dipole moment may be estimated. μ┴ = ε ε0 ΔV A

(3.1)

Where μ┴ is the dipole moment, ΔV is the surface potential and A is the molecular area These values at π = 20mN/m are shown in table 3.9. a)

16 12

0.030

16

0.025 0.06

12 2A

0.020

40

0.015

0.05

8

0.04

4

0.03

0 0.0

0.5

8

1.0

1.5

0.02

30

0.010 0.005

20

2.0

2.5

0.06

3A 0.05 0.04 0.03

0.000 3.0

0.02

2

Area/molecule(nm ) 10

4 0 0.0

c)

0.01

0.5

1.0

1.5

2.0 2

Area/molecule(nm )

0.00 2.5

0.01 0 0.0

0.5

1.0

0.00 2.0

1.5 2

Average area/molecule(nm )

Surface potential(V)

Surface pressure(mN/m)

20

20

Surface potenial(V)

24

0.035

1A

Surface potential(V) Surface pressure(mN/m)

Surface pressure(mN/m)

24

b)

Figure 3.46 π -A and ΔV- A isotherms of a) 1A, b) 2A and c) 3A The surface pressure – molecular area (π-A) and surface potential- area (ΔV-A) isotherms of 1B, 2B and are given in figure 3.47 a) b) and c). The isotherms show a liquid expanded state and corresponding μ┴ values are shown in table 3.9.

Surface pressure(mN/m)

70

0.030

1B

60

0.025

50

0.020

40 0.015 30 0.010

20

0.005

10 0 0.0

Surface potential(V)

a)

0.000 0.2

0.4

0.6

0.8

1.0

1.2

1.4

2

0.035

2B

40

0.030 30

0.025 0.020

20

0.015 0.010

10

0.005 0 0.0

0.2

0.4

0.6

0.8

1.0 2

Area/molecule(nm )

1.2

0.000 1.4

Surface potential(V)

b)

Surface pressure(mN/m)

Area/molecule(nm )

Surface pressure(mN/m)

40

3B 0.4

30 0.3 20

0.2

10

0.1

0 0.0

0.5

1.0

1.5

Surface potential (m/m)

0.5

c)

0.0 2.0

2

Area/molecule(nm )

Figure 3.47 π -A and ΔV- A isotherms of a) 1B, b) 2B and c) 3B Figure 3.48 a), b) and c) shows the surface pressure – molecular area (π-A) and surface potential- area (ΔV-A) isotherms of 1C, 2C and 3C respectively. Compound 1C has a ‘LE’ to LC transition. In compound 2C a phase transition intermediate to the 2-D gaseous and ‘LE’ is seen and the kink in the isotherm around 3mN/m suggests a fairly slow transition to the ‘LE‘state. The corresponding ΔV-A isotherms do not show this transition dramatically suggesting that the kink in the isotherm may arise due to the highly rigid nature of the head groups. In case of compound 3C, the transition from ‘LE’ to ‘LC’ state shows a plateau at about 5.2mN/m. The corresponding μ┴ components are given in table 3.9.

0.04

20

0.03

16 0.02

12 8

0.01 4 0 0.0

0.2

0.4

0.6

0.8 2

Area/molecule(nm )

0.00 1.0

28

0.12

2C

24

0.10

20

0.08

16 0.06 12 0.04

8

0.02

4 0 0.0

0.2

0.4

0.6

0.8 2

Area/molecule(nm )

0.00 1.0

Surface potential(V)

1C

24

Surface pressure(mN/m)

b)

28

Surface potential(V)

Surface pressure(mN/m)

a)

0.25

Surface pressure(mN/m)

24

3C

22 20

0.20

18 16

0.15

14 12 10

0.10

8 6

0.05

4 2 0

Surface potential(V)

c)

0.00 0

2 2

Area/molecule(nm )

Figure 3.48 π -A and ΔV- A isotherms of a) 1C, b) 2C and c) 3C The series of compounds containing the fluoro substituents show large negative surface potential values. These are typical of electronegative group in the amphiphile. The surface pressure–molecular area (π-A) and surface potential-area (ΔV-A) isotherms of 1B, 2B and are given in figure 3.49 a), b) and c). 1D and 3D show plateau between the ‘LE’ to ‘LC’ state with 3C with 3D showing a large plateau between areas of 0.6 and 0.3 Nm2/molecule. This again is due to the poor organized structures of the longer alkyl chains in compound 3D as against 1D. This poor packing combined with the loosely hydrated fluoro substituted head group that leads to the intermediate first order phase transition. b) -0.1

16 -0.2

12

-0.3

8 4 0 0.0

-0.4 0.5

1.0

1.5

2.0 2

Average area/molecule(nm )

0.05 24

0.00 -0.05

20

2D

-0.10

16

-0.15

12

-0.20 -0.25

8

-0.30 4 0 0.0

-0.35 0.2

0.4

0.6

0.8

1.0

1.2 2

Average area/molecule(nm )

-0.40 1.4

Surface potential (V)

1D

20

Surface Pressure(mN/m)

0.0

24

Surface potential(V)

Surface pressure(mN/m)

a)

0.00

20

3D

16

-0.05

12 -0.10 8 -0.15

4 0

Surface potential(V)

Surface pressure(mN/m)

c)

-0.20 0.2

0.4

0.6

0.8

1.0

1.2 2

Average area/molecule(nm )

Figure 3.49 π -A and ΔV- A isotherms of a) 1D, b) 2D and c) 3D Sample

1A 2A 3A 1B 2B 3B 1C 2C 3C 1D

Area at

Δv

π=

(V)

20mN/m 0.47 0.26 0.57 0.41 0.29 0.31 0.26 0.27 0.21 0.32

μ┴

Maximum surface pressure (mN/m)

0.024 0.054 0.036 0.014 0.019 0.428 0.033 0.093 0.213 -0.366

0.0298 0.0366 0.0535 0.0154 0.0150 0.3462 0.0224 0.0673 0.1163 -0.305

21.6 20.2 33.9 60.2 40.8 40.6 25.7 23.8 22.6 24.8 24.8 21.2

2D

0.32

-0.262

2 -0.218

3D

0.23

-0.176

5 -0.105 5

Table 3.9 Dipole moment, molecular area, surface potential and maximum surface pressure of the samples

After studying the samples as monolayers at the air/water interface they were coated as films on quartz plates and on cover slips. These films were characterized using fluorescence spectroscopy and contact angle measurements. 3.9 Fluorescence spectra of films Figures 3.50, 3.51, 3.52 and 3.53 show the fluorescence spectra of samples as films. The spectra show similar trend as the solution spectra, but surprisingly the emission spectra of films are well resolved than that of the solution. The reason for this may be there is better orientation of molecules in films compared to the molecules in solution. Anisotropy experiments were conducted in order to study the orientation of molecules in

films. The experiment was also done for bulk to compare the results with films. The results are tabulated and displayed in tables 3.10 and 3.11.

a)

b)

3.5

12 10 2A

2.5

1A

Intensity (a.u.)

Intensity (a.u.)

3.0

2.0 1.5 1.0

6 4 2

0.5 0.0 200

8

300

400

500

600

700

0 200

800

300

Wavelength (nm)

c)

400

500

600

700

Wavelength (nm)

300

Intensity (a.u.)

250

3A

200 150 100 50 0 200

300

400

500

600

700

800

Wavelength (nm)

Figure 3.50 Fluorescence spectra of films of a) 1A, b) 2A and c) 3A 250 1B

a)

Intensity (a.u.)

200 150 100 50 0 200

300

400

500

600

Wavelength (nm)

700

800

800

b) 80 70

Intensity (a.u.)

60

2B

50 40 30 20 10 0 200

300

400

500

600

700

800

Wavelength (nm)

120

c)

Intensity (a.u.)

100

3B

80 60 40 20 0 200

300

400

500

600

700

800

Wavelength (nm) 1.5

a)

Fluorescence spectra of films of a) 1B, b) 2B and Intensity (a.u.)

Figure 3.51 3B

1C

1.0

0.5

0.0 200

300

400

500

600

Wavelength (nm)

700

800

25

b)

Intensity (a.u.)

20

2C

15 10 5 0 200

300

400

500

600

700

800

Wavelength (nm) 60

c)

50

Intensity (a.u.)

3C 40 30 20 10 0 200

300

10

600

700

800

Fluorescence 1D spectra of films of a) 1C and

8

Intensity (a.u.)

a)

500

Wavelength (nm)

12

Figure 3.52 b) 2C and c) 3C

400

6 4 2 0 200

300

400

500

600

Wavelength (nm)

700

800

250

b)

2D

Intensity (a.u.)

200 150 100 50 0 200

300

400

500

600

700

800

Wavelength (nm) 40

c)

Intensity (a.u.)

30

3D

20

10

0 200

300

400

500

600

700

800

Wavelength (nm)

Figure 3.53 Fluorescence Spectra of films of a) 1D, b) 2D and c) 3D

Sample Wavelength

Ipa

Ipe

A=(Ipa-Ipe) /(Ipa+2Ipe)

1A 2A 3A 1B 2B 3B 1C 2C 3C 1D 2D 3D

485.3 485.3 466.9 479.8 421.0 434.2 488.9 486.5 485.3 485.3 490.5 488.9

0.2123 0.2101 0.1621 0.2234 0.1878 0.2878 0.1482 0.1796 0.1738 0.1367 0.1839 0.1492

0.0339 0.0305 0.0059 0.0582 0.1820 0.0716 0.1010 0.0268 0.1773 0.0960 -0.0247 0.0431

0.6369 0.6625 0.8982 0.4862 0.01051 0.5016 0.1348 0.6552 -0.00662 0.1238 0.6824 0.4507

Table 3.10 Fluorescence Anisotropy for sample as bulk

Sample Wavelength 1A 2A 3A 1B 2B 3B 1C 2C 3C 1D 2D 3D

473.7 339.6 693.1 630.4 335.6 727.1 439.5 422.7 496.5 426.2 588.8 569.8

Ipa

Ipe

0.2827 0.0167 0.2252 0.1063 0.2771 0.0622 0.2789 0.00814 0.1598 0.0470 0.2047 0.0543 0.1910 0.0800 0.2059 0.0480 0.2334 0.0859 0.2895 0.0071 0.2005 0.0336 0.2290 0.0441

A=(Ipa-Ipe) /(Ipa+2Ipe) 0.8415 0.2716 0.5352 0.9173 0.4444 0.4800 0.3162 0.5230 0.3640 0.9299 0.6234 0.5829

Table 3.11 Fluorescence Anisotropy for sample coated films

3.10 Contact angle measurements The hydrophilic or hydrophobic natures of the films were studied using contact angle measurements. Three sets of experiment were conducted by varying the

immersion depth and speed of immersion. Surface tension and contact angles were determined for each set. With those values, other parameters such as work of adhesion were calculated using the equations given in chapter 2.Table 3.12, 3.13 and 3.14 gives the results obtained from contact angle measurements. Contact angle measurements were also done for sample coated on hydrophobically modified glass plate. The results are presented in table 3.15.

Sample

1A γ LV

θs θa θr

2A γ LV

θs θa θr

3A γ LV

θs θa θr

1B γ LV

θs θa θr

2B γ LV

θs θa θr

3B γ LV

θs θa θr

1C γ LV

θs θa θr

2C γ LV

θs θa θr

Surface Tension (mN/m) &Contact Angle (°) Water DMSO Alkane

γ sd

γ s+

γ s-

γ sp

γs

γ sld

Work of Adhesion

65.8 61.4 62.7 05.6

45.3 29.0 33.9 03.1

25.1 16.4 18.8 08.2

24.09 23.78 25.10

5.29 4.63 7.23

12.92 13.23 42.18

16.54 15.65 34.92

40.62 39.43 60.02

1.126 1.059 1.352

97.30 95.98 131.3

65.2 64.0 70.8 13.4

45.5 40.1 50.9 04.0

27.9 27.8 32.3 10.2

24.77 23.75 27.46

3.31 1.93 6.13

14.08 14.16 40.32

13.65 10.45 31.44

38.42 34.20 58.90

1.461 1.221 2.167

93.78 86.64 128.6

64.7 62.5 57.7 0

45.0 37.1 45.4 18.2

26.6 21.8 23.1 10.6

24.73 24.51 26.15

3.52 2.31 5.44

14.78 21.92 45.32

14.42 14.22 31.40

39.15 38.73 57.55

1.617 1.561 1.995

94.57 99.27 129.4

71.4 55.1 68.7 0

43.7 13.5 13.7 02.5

28.5 21.9 19.6 11.2

26.48 26.87 27.96

4.67 4.48 4.46

18.94 08.32 53.24

18.80 12.21 30.84

45.28 39.08 58.80

0.396 0.445 0.595

112.2 97.34 142.7

68.9 66.2 73.1 03.4

47.1 38.6 49.5 04.5

27.1 10.8 11.5 0

26.62 26.56 27.10

3.78 1.96 7.79

10.95 09.53 41.98

12.87 08.65 36.17

39.49 35.21 63.27

0.862 0.852 0.950

96.70 88.93 137.7

61.6 68.6 74.2 01.5

46.0 47.0 61.1 05.4

28.5 18.1 64.2 14.1

27.11 26.05 27.65

1.73 0.38 6.43

13.34 14.84 39.31

09.61 04.76 31.8

36.72 30.81 59.45

3.805 3.416 4.010

84.08 78.37 123.2

53.1 67.6 69.0 0

47.7 40.7 49.5 04.4

26.3 09.9 13.4 02.0

25.91 25.59 26.28

4.05 2.52 8.89

14.34 16.82 36.74

15.26 13.03 36.15

41.16 38.62 62.43

13.26 13.03 13.52

73.33 72.13 106.2

57.5 80.6 86.8 11.7

46.5 40.3 45.0 06.8

27.7 19.2 20.0 09.2

26.18 26.05 27.34

3.30 2.57 6.99

04.94 03.35 35.80

08.08 05.87 31.65

34.26 31.92 58.99

6.590 6.525 7.178

66.89 60.71 113.8

3C γ LV

θs θa θr 1D γ LV

θs θa θr 2D γ LV

θs θa θr 3D γ LV

θs θa θr

63.1 50.9 64.5 0

46.8 36.6 45.9 09.7

27.9 21.9 23.7 10.1

25.92 25.60 27.47

4.28 2.72 7.05

21.28 14.47 38.82

19.08 12.54 33.08

45.00 38.14 60.55

2.601 2.500 3.107

102.9 90.26 126.2

65.4 59.2 64.7 09.6

46.5 37.9 45.1 09.6

28.6 20.6 18.8 3.85

26.80 27.09 28.53

3.47 2.22 6.24

16.31 14.75 40.32

15.04 11.45 31.71

41.84 38.54 60.24

1.910 1.988 2.392

98.89 93.35 129.9

63.4 71.6 74.2 14.2

46.6 43.9 53.8 11.9

27.9 23.7 27.3 09.9

25.59 24.88 27.49

2.96 1.59 6.69

09.06 10.55 37.44

10.36 08.19 31.67

35.95 33.07 59.16

2.363 2.151 2.964

83.41 80.66 124.9

67.2 55.3 68.5 13.8

44.5 39.3 48.3 09.9

28.3 19.8 20.4 11.4

26.65 26.55 27.74

2.26 1.18 4.94

23.28 15.22 44.83

14.49 08.46 29.75

41.14 35.01 57.49

1.294 1.272 1.542

105.5 91.83 132.5

Table 3.12 Surface tension and Contact angle measurements of sample coated cover slips taken with immersion depth 1mm and speed of immersion 5mm/min

1 2

46

14

44

12

42

10 40

γ SL (mN/m)

38

d

γ S (mN/m)

1 2

36

8 6 4 2

34 A

B

C

Compound

D

0 A

B

C

Compound

D

120

1 2

W adhesion (mJ/m 2)

110 100 90 80 70 60

A

B

C

D

Compound

1 3

46 45

14

44

12

43

10

γ SL (mN/m)

41 40 39

d

38

8 6 4

37

2

36

0 A

B

C

D

A

Compound

B 120

C

D

Compound 1 3

110

W adhesion (mJ/m 2)

γ S (mN/m)

42

35

1 3

100 90 80 70

A

B

C

Compound

D

Sample

1A γ LV

θs θa θr

2A γ LV

θs θa θr

3A γ LV

θs θa θr

1B γ LV

θs θa θr

2B γ LV

θs θa θr

3B γ LV

θs θa θr

1C γ LV

θs θa θr

2C γ LV

θs θa θr

Surface Tension (mN/m) &Contact Angle (°) Water DMSO Alkane

γ Sd

γ S+

γ S-

γ Sp

γS

γ SLd

Work of Adhesion

66.9 61.4 63.3 15.6

47.3 29.0 38.8 9.47

24.8 16.4 14.1 0

23.80 24.06 24.80

7.08 5.00 9.14

10.77 12.19 36.59

17.47 15.61 36.57

41.27 39.67 60.63

0.794 0.842 0.842

98.92 96.96 131.34

62.0 64.0 69.3 14.4

47.6 40.1 51.6 8.4

27.2 27.8 26.7 9.0

24.15 24.38 26.87

4.89 2.51 8.24

11.49 12.13 33.74

15.00 11.03 33.36

39.15 35.41 59.23

2.55 2.63 3.49

89.18 83.91 122.05

67.7 62.5 58.9 0

46.1 37.1 46.9 2.5

27.8 21.8 28.7 7.7

25.85 24.49 27.55

3.73 2.59 6.65

14.08 20.71 43.35

14.50 14.65 33.95

40.35 39.14 61.50

0.995 0.743 1.351

98.96 102.7 135.4

71.2 55.1 57.5 6.1

43.5 13.5 22.6 9.4

28.8 21.9 21.2 14.9

26.74 26.90 27.84

4.41 3.58 4.39

19.20 18.73 52.84

18.39 16.39 30.45

45.13 43.29 58.29

0.458 0.479 0.611

111.9 109.5 141.9

70.1 66.2 72.8 0

46.4 38.6 48.2 1.5

28.8 10.8 19.2 7.1

28.29 27.22 28.58

2.77 1.69 6.41

12.07 10.09 45.22

11.57 08.27 34.04

39.86 35.49 62.62

0.899 0.717 0.952

98.39 90.83 140.2

66.7 68.6 64.6 13.8

43.4 47.0 50.1 0

27.7 18.1 25.4 9.6

26.35 25.09 26.14

1.02 0.97 5.06

15.83 20.46 45.66

8.02 8.89 30.39

34.37 33.99 56.54

1.37 1.09 1.32

91.04 95.31 131.5

57.4 67.6 71.2 10.2

46.6 40.7 55.6 4.8

27.5 9.9 9.7 4.1

27.09 27.11 27.43

2.96 0.85 7.12

12.39 15.86 35.82

12.12 7.35 31.94

39.21 34.46 59.37

7.16 7.16 7.33

81.93 75.90 113.9

57.1 80.6 91.4 7.5

46.1 40.3 41.6 6.6

27.4 19.2 19.4 3.0

25.90 25.87 27.36

3.18 2.98 6.63

05.31 01.69 37.53

8.22 4.49 31.54

34.12 30.36 58.9

6.86 6.85 7.62

66.42 55.70 113.7

3C γ lv

θs θa θr 1D γ lv

θs θa θr 2D γ lv

θs θa θr 3D γ lv

66.8 50.9 58.8 0

48.6 36.6 47.1 3.7

25.9 21.9 21.9 11.5

24.06 24.06 25.38

6.46 4.07 10.49

19.21 17.32 36.29

22.28 16.79 39.02

46.34 40.85 64.40

0.86 0.86 1.13

108.9 101.4 133.6

63.9 59.2 64.6 5.02

45.8 37.9 43.9 7.5

25.9 20.6 13.6 0

24.27 25.18 25.90

4.07 2.69 7.09

16.37 14.66 40.28

16.32 12.58 33.81

40.59 37.76 59.71

1.78 2.03 2.24

96.62 91.31 127.6

66.0 71.6 74.2 14.2

45.3 43.9 55.3 12.3

26.1 23.7 12.6 0

23.94 25.48 26.10

2.89 0.86 6.23

9.89 2.97 43.09

10.69 3.15 32.79

34.63 28.63 58.89

1.04 1.38 1.53

86.83 65.88 131.1

67.9 55.3 67.6 8.9

45.9 39.3 47.5 6.9

7.4 19.8 16 0

25.80 2.92 20.62 15.51 42.07 1.21 105.11 θs 26.35 2.35 11.77 10.53 36.83 1.11 91.93 θa 27.40 4.39 47.88 28.99 56.46 1.36 135.2 θr Table 3.13 Surface tension and Contact angle measurements of sample coated cover slips taken with immersion depth 1mm and rate of immersion 2mm/min

46

1 2

8

1 2

44 6

γ SL (mN/m)

40 38

4

2

W adhesion (mJ/m 2)

36

0

34 A

B

C

Compound

D

115

1 2

110

d

γ S(mN/m)

42

105 100 95 90 85 A

B

80

Compound

C

D

75 70 65 A

B

C

Compound

D

A 2B γ LV

θs θa θr

3B γ LV

θs θa θr

1C γ LV

θs θa θr

2C γ LV

θs θa θr

B

C

70.6Compound 48.1 62.8 29.0 70.9 38.1 2.5 6.7

γ S-

γ Sp

γS

γ SLd

23.53 23.66 24.84 25.01 23.87 26.30 26.02 26.35 27.3 23.41 1 23.19 3 26.75 26.05 25.25 25.92 24.45 24.56 25.52 26.56 23.30 27.47 27.25 27.57 28.08

8.91 8.12 11.44 6.48 7.91 7.93 3.729 2.30 5.99 5.19 4.04 7.64 0.957 0.457 5.52 4.07 3.08 7.52 2.92 2.35 4.39 5.24 4.96 5.42

8.40 3.57 34.82 11.18 5.32 39.79 19.00 18.65 46.35 3.97 8 10.25 35.55 7 14.40 19.91 6 38.59 5 16.70

17.30 10.77 39.92 16.99 12.98 35.53 16.84 13.10 33.34 9.08 12.86 32.96 7.42 6.03 29.20 16.48 10.99 35.63 15.51 10.53 28.99 18.03 14.48 32.67

40.83 34.43 64.76 42.19 36.85 61.83 42.86 39.45 60.64 32.49 36.05 59.71 33.47 32.08 55.12 40.93 35.55 61.15 42.07 36.83 56.46 45.28 42.05 60.75

0.835 0.859 1.08 1.29 0.99 1.54 0.778 0.835 1.012 2.55 2.48 3.73 3.83 3.83 3.78 0.99 1.01 1.21 1.21 1.11 1.36 0.594 0.641 0.721

9.82 4 42.19 20.62 3 11.77 2 47.88 15.53 1 10.57 0 49.22

D 26.8 26.7 26.8 5.7

24.02 23.99 26.67

A 7.68 5.77 8.98

9.72 6.66 41.61

17.28 12.40 115 19.33

B

Work of Adhesion 97.62 86.16 133 98.45 89.68 132.0 106.6 102.3 137.6 77.49 83.84 1 121.7 3 80.32 83.52 118.5 100.7 88.50 133.2 105.1 91.93 135.2 109.4 102.1 141.5

C

Compound

D

41.30 36.39 46.00

0.224 0.222 0.543

102.9 93.70 141.1

1 3

110 63.0 62.1 67.9 6.69

45.6 50.4 56.5 0

27.0 21.1 20.9 14.2

25.22 25.25 26.18

1.62 0.856 6.39

19.70 17.74 40.90

105 11.30 7.79 100 32.33 95

36.52 33.05 58.51

2.43 2.44 2.73

92.48 86.70 125.57

57.3 63.2 69.6 10.3

49.3 42.8 47.5 3.2

28.8 21.8 20.4 9.7

26.78 27.02 28.39

4.27 3.19 9.34

12.91 10.75 30.81

90 14.84 85 11.72 33.93 80

41.62 38.74 62.32

7.10 7.23 7.94

83.13 77.27 113.7

51.8 79.1 73.7 0.37

47.1 39.1 48.1 3.0

28.0 24.2 22.8 9.9

B

C

2

θa θr

34

γ S+

W adhesion (mJ/m )

2A θa γ LV θr θ s 2D θ a γ LV 46 θ θ rs 443A θa γ LV θr 42θ s 3D θa 40γ LV θr θs 381B θ a γ LV 36θ θ rs

γ Sd

d

γ S(mN/m)

θs 1A θa γ LV θr θ s 1D θ a γ LV θ θ rs

Surface Tension (mN/m) &Contact Angle (°) 66.5 49.2 24.9 Water DMSO Alkane 62.1 29.6 19.2 72.8 32.7 18.3 66.1 46.7 26.7 0 6.5 3.8 60.7 25.1 19.4 69.1 20.5 27.0 68.8 45.2 27.3 4.45 0 9.9 56.7 33.1 17.7 60.9 42.0 15.2 61.5 46.7 27.0 1.66 0 0 77.8 37.3 30.4 68.7 43.6 31.4 60.9 44.2 27.5 12.0 2.9 7.8 71.4 50.5 18.8 68.2 57.5 23.6 66.6 46.0 25.9 18.9 10.3 12.1 59.2 38.2 19.4 70.8 43.6 18.6 67.6 43.3 27.5 0 7.1 9.8 56.3 29.0 15.1 68.9 34.7 17.05 70.8 45.3 28.3 0 0 2.7 57.0 17.4 15.7 63.8 18.7 13.1 2.56 9.92 7.23

γ SL (mN/m)

3C Sample γ LV

A 25.59 25.85 27.58

4.11 2.10 7.56

10.08 16.96 43.26

12.88 12.77 36.18

38.47 38.62 63.76

17.34 61.59 Compound 17.55 66.34 18.98 103.6

D

Table 3.14 Surface tension and Contact angle measurements of sample coated cover slips taken with immersion depth 2mm and rate of immersion 5mm/min 1 2

46

18

44

1 2

16 14

42

γ SL (mN/m)

38 36

10 8 6

d

γ S(mN/m)

12 40

4

34

2

32

0 A

B

C

D

110

Compound

A

B

C

D

Compound

105 100

W adhesion (mJ/m 2)

95 90 85 80 75 70 65 60 A

B

C

D

Compound 1 3

8

44

1 2

7 6

γ SL (mN/m)

40

d

γ S(mN/m)

42

38 36

5 4 3 2 1

A

B

C

Compound

D

0

A

B

C

Compound

D

1 2

1A 2A 3A 1B 2B 3B 1C 2C 3C 1D 2D 3D

Water

θs DMSO

72 73 72 73 70 79 78 75 76 78 71 77

63 64 64 65 60 62 59 57 65 68 57 70

Alkane

γ Sd

γ S+

γ S-

γ Sp

γS

γ SLd

Work of Adhesion

24 24 25 28 110 30 105 29 100 23 95 21 90 26 85 23 80 23 19 75

24.76 24.76 24.57 23.98 23.55 23.76 24.94 25.28 24.38 24.92 24.94 25.60

0.142 0.099 0.113 0.115 0.471 0.297 0.354 0.455 0.087 0.002 0.504 0.022

19.83 19.31 20.35 19.75 20.20 1 3 12.45 12.19 14.04 16.71 16.30 17.83 16.01

3.36 2.78 3.04 3.01 6.17 3.84 4.16 5.05 2.42 0.39 5.99 1.18

28.12 27.84 27.61 26.99 29.72 27.60 29.10 30.33 26.80 25.34 30.94 26.78

0.108 0.108 0.096 0.062 0.042 0.051 0.120 0.145 0.084 0.120 0.120 0.169

95.03 93.83 95.03 93.83 97.43 86.45 87.69 91.39 90.16 87.69 96.24 88.93

W adhesion (mJ/m 2)

Sample

70 65 60 A

B

C

D

Compound

Table 3.15 Contact angle measurements of hydrophobically modified glass plates coated with samples