4(%3)3 - Ecole nationale supÃ©rieure de chimie de Montpellier

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100Retention (%)8060400,100,20,40,60,820070 95 120 145 170 195 220Particle Diameter (nm)Figure – 3.17: The calculated retention values for poly(styrene) NPs at different pressures as a function of particlediameter.At 0.1 bar, particles of all sizes were retained however at 0.8 bar all of them passed through. Inbetween these two values, the retention of particles with higher diameter contributed principally to theobserved global retention values at given pressure. Given the low porosity of the membrane only 6 % at0.8 bar, it is remarkable though not surprising that nearly all the particles with such huge diameter wereable to pass through the membrane without damaging it at all. At this point it can be concluded that duedynamic nature of the membrane, we were able to change the pore size with pressure to be able totranslocate big nano-objects. To further prove this, top and bottom surface images of one suchmembrane was obtained by using Scanning Electron Microscopy (Figure – 3.18a,b,c), which showed thepresence of NPs in significant amounts on both surfaces however no physical damage was observed tothe membrane.The reason for such non-damaging translocation can be explained by the self-healing nature ofthe membrane. At the onset of the translocation process, the particle is compressed against the surfaceof the membrane due to the water pressure. As more and more compression takes place, the particletends to push itself more inside the membrane thus constraining the dynamic bridges between themicelles. Once these bridges are dislodged from one end, the particle enters inside and continues to bepushed further deep, dislodging the forward direction bridges. However behind the particle, the90
dislodged bridges are again restored by the virtue of copolymer chains’ mobility and micelles’compression thereby effectively closing the membrane. The healing scars (Figure – 3.18c) found on theback side of membrane having sizes approximate to that of translocated NPs reinforcing the aboveargument of self-healing.91
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THESISPRESENTED ATNATIONAL GRADUATE
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As the human civilization progress
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CHAPTER - 1 SELF-HEALING POLYMERIC
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8.1.5 Atomic Force Microscopy …
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Synthetic engineering materials in
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esponse to a specific external stim
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The first work based on this approa
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een prepared from urea-formaldehyde
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monomer systems. The addition of EN
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Figure - 1.10: Self-healing process
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was required to reach healing effic
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In addition to above works, some ot
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that have been identified to be tak
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part of the chapter, these material
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Figure - 1.17: Self-healing of the
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commercialized under tradenames; Nu
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joined together at temperature high
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Inspired by these findings, the fir
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temperature greater than 80 o C in
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Figure - 1.27: Sulfur chemistry bas
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A different kind of sulfur chemistr
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Figure - 1.29: Dynamic covalent che
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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 62 and 63: the micelle assembly showed the pre
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 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,
Page 112 and 113: 46 Bemporad, D., Luttmann, C. & Ess
Page 114 and 115: In this chapter, preparation of 3D
Page 116 and 117: obtain complex macromolecular archi
Page 118 and 119: The polymerization was conducted at
Page 120 and 121: proceeds, lesser monomer is availab
Page 122 and 123: mg/ml),the micelles’ hydrodynamic
Page 124 and 125: Figure - 4.15: The monolayer and mu
Page 126 and 127: monolayer of micelles and topmost l
Page 128 and 129: The presence of the dispersed micel
Page 130 and 131: Heating the multilayer micelle asse
Page 132 and 133: stable zipping of the micelles. Mul
Page 134 and 135: 24 Moad, G., Rizzardo, E. & Thang,
Page 136 and 137: The concept of nano-gel based self-
Page 138 and 139: Figure - 5.4: Size distribution of
Page 140 and 141: In a typical process, the two compo
Page 142 and 143: Figure - 5.10: 1HNMR spectra obtain
Page 144 and 145: The 1 HNMR spectrum obtained for th
Page 146 and 147: REFERENCES1 White, S. R. et al. Aut
Page 148 and 149: 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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