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the micelle assembly showed the presence of multiple cracks, possibly due to weaker inter-micelleinteractions. The AFM image of a crack is shows individual 50 nm micelles aligned in short rods along thecracks. It should be noted that decreasing dramatically the block A does not alter the possibility ofgenerating flower-like micelles; however it seems to reduce bridge proportion. An explanation could bethat a shorter block A is unable to reach the hydrophobic core of another micelle while crossing itshydrophilic shell.Figure – 2.6: Scanning Electron Microscopy image (a) and Atomic Force Microscopy image (b) for copolymer filmprepared from PSAN(7.5k)-b-PEO(35k)-b-PSAN(7.5k). Despite successful assembly, the film suffers from large voidsformation due to insufficient length of PSAN block which effects the formation of bridges in between the micellesTo detect the micelle assembly, Quartz Crystal Microbalance** (QCM) was used by injectingmicellar solutions at different block copolymer concentrations onto gold-coated QCM electrodes. Whilethe PSAN(47k)-b-PEO(35k)-b-PSAN(47k) showed a clear micelle adsorption after injection (Figure – 2.7a),the PSAN(7.5k)-b-PEO(35k)-b-PSAN(7.5k) micelle adsorption was found to be very low and unstable(Figure – 2.7b). Given the fact that the gold-coated electrode is highly hydrophobic therefore only thepresence of dangling hydrophobic blocks can explain the adsorption through hydrophobic interactions.52
Figure – 2.7: Quartz Crystal Microbalance measurements for the two copolymers having different PSAN blocklength, a) PSAN(47k)-b-PEO(35k)-b-PSAN(47k) shows stable and strong bridging characteristics as can be seen byhigh increase in frequency, b) PSAN(7.5k)-b-PEO(35k)-b-PSAN(7.5k) shows very unstable assembly as the frequencygain is very low and unstable suggesting that despite micelles formation, they are not able to hold each other thusfalling apart resulting in overall loss of mass.Figure – 2.8: Evolution of frequency in response to concentration change for the two copolymers.For each concentration, injections were repeated (2-3 times) until reaching a maximum value offrequency F (Figure – 2.8 F with the concentration was observed forPSAN(47k)-b-PEO(35k)-b-PSAN(47k) rather than a stable value. It can be explained by the micelleassociation through bridging conformations beyond a threshold concentration thus increasing the mass53
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THESISPRESENTED ATNATIONAL GRADUATE
Page 4 and 5:
As the human civilization progress
Page 6 and 7:
CHAPTER - 1 SELF-HEALING POLYMERIC
Page 8:
8.1.5 Atomic Force Microscopy …
Page 11 and 12: Synthetic engineering materials in
Page 13 and 14: esponse to a specific external stim
Page 15 and 16: The first work based on this approa
Page 17 and 18: een prepared from urea-formaldehyde
Page 19 and 20: monomer systems. The addition of EN
Page 21 and 22: Figure - 1.10: Self-healing process
Page 23 and 24: was required to reach healing effic
Page 25 and 26: In addition to above works, some ot
Page 27 and 28: that have been identified to be tak
Page 29 and 30: part of the chapter, these material
Page 31 and 32: Figure - 1.17: Self-healing of the
Page 33 and 34: commercialized under tradenames; Nu
Page 35 and 36: joined together at temperature high
Page 37 and 38: Inspired by these findings, the fir
Page 39 and 40: temperature greater than 80 o C in
Page 41 and 42: Figure - 1.27: Sulfur chemistry bas
Page 43 and 44: A different kind of sulfur chemistr
Page 45 and 46: Figure - 1.29: Dynamic covalent che
Page 47 and 48: cracks. The recovered droplets afte
Page 49 and 50: 23 White, S. R. et al. Autonomic he
Page 51 and 52: 65 Taber, D. F. & Frankowski, K. J.
Page 53 and 54: 107 Kushner, A. M., Vossler, J. D.,
Page 55: 148 Park, J. S., Kim, H. S. & Hahn,
Page 58 and 59: The value of subscripts “n”,
Page 60 and 61: The formation of spherical micelles
Page 64 and 65: gain onto the electrodes by buildin
Page 66 and 67: The resistance R can be further exp
Page 68 and 69: empty-tower velocity U only depends
Page 70 and 71: This apparent morphological switchi
Page 72 and 73: In a further qualitative analysis,
Page 74 and 75: noteworthy and though its feasibili
Page 76 and 77: Furthermore within this range, lowe
Page 78 and 79: Figure - 2.22: Scanning Electron Mi
Page 80 and 81: While the resistance measurements g
Page 82 and 83: In conclusion, a self-healing membr
Page 84 and 85: 23 Giacomelli, F. C., Riegel, I. C.
Page 86 and 87: micelles enabled the membrane to se
Page 88 and 89: The second class is represented by
Page 90 and 91: To avoid the probable clogging of t
Page 92 and 93: 181614SP2 - iNumber of Particles121
Page 94 and 95: 1000900800y = 3E+06xR² = 0,9911y =
Page 96 and 97: very high value of 1.5 g.l -1 . Thi
Page 98 and 99: Since the only change in the membra
Page 100 and 101: 100Retention (%)8060400,100,20,40,6
Page 104 and 105: (Figure - 3.20). A cursory look at
Page 106 and 107: When compared to poly(styrene) NPs,
Page 110 and 111: REFERENCES1 Metzler, R. & Klafter,
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46 Bemporad, D., Luttmann, C. & Ess
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In this chapter, preparation of 3D
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obtain complex macromolecular archi
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The polymerization was conducted at
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proceeds, lesser monomer is availab
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mg/ml),the micelles’ hydrodynamic
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Figure - 4.15: The monolayer and mu
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monolayer of micelles and topmost l
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The presence of the dispersed micel
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Heating the multilayer micelle asse
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stable zipping of the micelles. Mul
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24 Moad, G., Rizzardo, E. & Thang,
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The concept of nano-gel based self-
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Figure - 5.4: Size distribution of
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In a typical process, the two compo
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Figure - 5.10: 1HNMR spectra obtain
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The 1 HNMR spectrum obtained for th
Page 146 and 147:
REFERENCES1 White, S. R. et al. Aut
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healing ability shown by the membra
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7. PERSPECTIVESBeing the first such
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8. MATERIALS & METHODSThis chapter
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8.1.3 PEG Filtration MeasurementsTh
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addition of TEOS due to formation o
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solution was ultrasonicated for 15
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Triethylamine (TEA) (Sigma-Aldrich
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To prepare the monolayer assembly o
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was added followed by addition of 0
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ELABORATION OF SELF-HEALING POLYMER
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ELABORATION DES MEMBRANES POLYMERES
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4(%3)3 - Ecole nationale supÃ©rieure de chimie de Montpellier

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