Swelling of poly

Figure 9 The equations of motion (TF theory) correlate swelling of poly(A-isopropyl acrylamide) caused by an increase in temperature from 10 to 25°C. D = 2.5 X 10 7 cm2/s L0 = 1.5 mm. (Adapted from Ref. 84.)...

Jaczewska, J. Raptis, I. Budkowski, A. Goustouridis, D. Raczkowska, J. Sanopoulou, M. Pamula, E. Bemasik, A. Rysz, J., Swelling of poly(3 alkylthiophene) films exposed to solvent vapors and humidity Evaluation of solubility parameters, Synth. Met. 2007, 157, 726 732... 

Based on the solution property of poly (DMAEMA-co-AAm) in response to temperature, the temperature dependence of equilibrium swelling of poly (DMAEMA-c6>-AAm) gel as a function of chemical composition was observed as shown in Figure 6. The transition temperature of copolymer gel between the shrunken and swollen state was shifted to the lower temperature with increases in AAm content in the gel network. This is attributed to the hydrogen bond in the copolymer gel network and its hydrophobic contribution to the LCST Copolymer II gel was selected as a model polymer network for permeation study because it showed the sharp swelling transition around 34°C. 

Gemeinhart, R.A., H. Park, and K. Park. 2001. Effect of compression on fast swelling of poly(acrylamide-co-acrylic acid) superporous hydrogels. J Biomed Mater Res 55 54. 

A. Loxley and B. Vincent, Equilibrium and kinetic aspects of the pH swelling of poly(vinylpyridine) latex particles, Colloid Polymer Sci. 275, 1108-1114 (1997). 

Later, they reported the photoregulation of the degree of ionization and swelling of poly(methacrylic acid) membrane cross-linked with 1 mol-% ethylene glycol dimethacrylate onto which positively charged p-phenylazophenyltrimethylammonium ions (PTA) were absorbed (Eq. (9)). 

Figure 2. Swelling of poly(methyl methacrylate) latexes with methyl methacrylate comparison of experimental data with theoretical curves from Model 1. Key ,...

Loxley, A. Vincent, B. Equilibrium and kinetic aspects of the pH-dependent swelling of poly (2-vinylpyridine-co-styrene) microgels. Colloid Polym. Sci. 1997, 275 (12), 1108-1114. 

Fig. 21 (a) Zeta potential and degree of swelling of poly(NaAMPS-co-DMAAm) gels as a func-... 

P1N Pini, R., Storti, G., Mazzotti, M., Tai, H., Shakesheff, K.M., and Howdle, S.M., Sorption and swelling of poly(DL-lactic add) and poly(lactic-co-glycolic acid) in supercritical CO2, Macromol. Symp., 259,197,2007. 

ROY Royer, J.R., DeSimone, J.M., and Khan, S.A., Carbon dioxide-indirced swelling of poly(dimetltylsiloxane),Macrowo/ecM/e5, 32, 8965, 1999. 

SIR Sirard, S.M., Green, P.F., and Johnston, K.P., Spectroseopie ellipsorrretry investi tion of the swelling of poly(dimethylsiloxane) thin films with high pressure earbon dioxide, J. Phys. Chem. B, 105, 766, 2001. 

Kishi R, Sisido M, Tazuke S (1990) Liquid-crystalline polymer gels. 2. Anisotropic swelling of poly(y-benzyl L-glutamate) gel crosslinked under a magnetic field. Macromolecules 23 3868-3870... 

Nichols, M. D., E. A. Scott, et al. (2009). Factors affecting size and swelling of poly(ethylene glycol) microspheres formed in aqueous sodium sulfate solutions without surfactants. Biomaterials 30(29) 5283-5291. 

Figure 7 showed that neither NaCl nor CaCl2 affected the swellability of poly (PVA-MA) at pH 5 and below. However, NaCl suppressed the expansion significantly between pH 5 and 7. It has been reported that urea enhanced the pH-induced swelling of poly-HEMA hydrogel doped with methacrylic acid. However, we have found fhat urea suppressed the expansion of poly(PVA-MA). 

RESULTS AND DISCUSSION Swelling of Poly(ether-urethanes)... 

Work discussing the theory of microgel swelling has been published by a number of groups. A model for describing the swelling of poly(NIPAM) networks has been employed by... 

Bittrich, E., Burkert, S., Muller, M., Eichhorn, K.-J., Stamm, M., Uhlmann, P. (2012). Temperature-sensitive swelling of poly(N-isopropylacrylamide) brushes with low molecular weight and grafting density. Langmuir The ACS Journal of Surfaces and Colloids, 28, 3439-3448. 

Li and Aoki [1019] observed a large swelling of poly(3-hejqrl-thiophene) films prepared chemically and subsequently oxidized electrochemically in a nonaqueous solution after transfer into chloroform. More highly oxidized films showed a greater swelling. The shift of the absorbance at A = 302 nm, attributed to the... 

In the case of non-aqueous dispersions the presence of compound L in phase (a) is expected to be more pronounced and should always be included in the thermodynamic treatment of swelling. To the present authors knowledge, the thermodynamics of swelling of particles in non-aqueous dispersions has not been systematically treated. A special case of swelling of polymer particles in "non-aqueous" systems is the swelling of poly(vinyl chloride) precipitated within droplets of vinyl chloride. This case is discussed below in connection with phase separation during swelling. 

Mrozek, R. A. Cole, P. J. Otim, K. J. Shull, K. R. Lenhart, J. L. (2011). Influence of Solvent Size on the Mechanical Properties and Rheology of Polydimethylsiloxane-based Polymeric Gels. Polymer, Vol. 52, pp. 3422-3430, ISSN 0032-3861 O Connor, A. E. Willenbacher, N. (2004). The Effect of Molecular Weight and Temperature on Tack Properties of Model Polyisobutylenes. International Journal of Adhesion Adhesives, Vol. 24, pp. 335-346, ISSN 0143-7496 Patel, S. K Malone, S. Cohen, C. Gillmor, J. R. Colby, R. H. (1992). Elastic Modulus and Equilibrium Swelling of Poly(dimethylsiloxane) Networks. Macromolecules, Vol. 25, pp. 5241-5251, ISSN 0024-9297... 

Fig. 1 Effect of the addition of NaCI and 1,3-dimethylurea on the temperature dependence of the degree of swelling of poly(N-isopropylacrylamide) gels.

Fig. 5 Temperature dependence of the swelling of poly(vinyl methylether) gel.

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