Hydrogels swelling characteristics

Table 10. Characteristics of hydrogel swelling and efficiency as a soil additive1 [139]...

DC Harsh, SH Gehrke. Controlling the swelling characteristics of temperature-sensitive cellulose ether hydrogels. J Controlled Release 17 175-186, 1991. 

In consideration of the clinical importance of being able to visualize any implant material within the body, radio-opaque hydrogels for NPR have been formulated [69]. Copolymers of iodobenzoyl-oxo-ethyl methacrylate (4IEMA) and hydrophilic PVP or hydroxylethyl methacrylate (HEMA) exhibit appropriate swelling characteristics, viscoelastic mechanical properties, and excellent cytocompatibility [69]. Moreover, inclusion of the covalently attached iodine molecules allowed for hydrogel visualization via X-ray in a porcine cadaveric spine model [69],... 

Hydrogels are also used as breast prostheses, due to their swelling characteristics, which make them similar to live tissue. Medical follow-ups of implanted women indicate that these implants remain soft after 18 8 months. However, all the results are not equally concordant because breast prostheses with textured surfaces and filled with PVP hydrogel undergo a significant increase in volume when implanted in patients as a consequence of osmosis. ... 

Fig. 19 Swelling characteristics of hydrogel components at (a) different channel cross-sections Ac and (b) various counterforces. As hydrogel a poly(vinyl alcohol) / polyacrylic acid network is used (Arndt et al. 1999)...

Choia SH, Whang KS, Park Jong-Soo, Choi Woo-Young, Yoon MH. Preparation and swelling characteristics of hydrogel from microbial poly(Y-glutamic acid) by y-ittadiation. Macromol Res 2005 13 339 3. 

TABLE 12.1 Composition detail and swelling characteristic of studied super absorbent hydrogels (Aj-Aj)... 

The hydrophilicity of the hydrogel system can also be expressed by means of an interaction parameter (x). This parameter defines the interaction energy during the process of hydration. The parameter is determined experimentally from stress-strain cnrves and the swelling characteristics of the hydrogel using the Flory-Hnggins eqnation,... 

I. El-Sherbiny, E. Abdel-Bary, and D. Harding, Swelling characteristics and in vitro drug release study with pH-and thermally sensitive hydrogels based on modified chitosan. Journal of Applied Polymer Science, 102 (2), 977-985,2006. 

Lee Y M, Kim S H and Cho C S, Synthesis and swelling characteristics of pH and thermo-responsive interpenetrating polymer network hydrogel composed of poly(vinyl alcohol) and polyfacryUc acid) , J. Appl. Polym. Sci., 1996, 62, 301. 

Pandaa A.S.B.M., Sabharwalb S., Bhardwajb YK. and MajaUb A.B. (2000), Synthesis and swelling characteristics of poly (N-isopropylacrylamide) temperature sensitive hydrogels crosslinked by electron beam irradiation. Radiation Physics and Chemistry, 58(1) pp. 101-110. 

Such processes have led to a wide range of swellable hydrogels as Gregonis, etal. [19], Peppas [1] and others have pointed out. Tables 1 and 2 summarize, for example, some of the important hydroxylated methacrylate polymers and the swelling characteristics of their hydrogels. 

Knowledge of the swelling characteristics of a polymer is of utmost importance in biomedical and pharmaceutical applications since the equilibrium degree of swelling influences the solute diffusion coefficient through these hydrogels [1], the surface properties and surface mobility [1,2,8], the optical properties, especially in relation to contact lens applications, and the mechanical properties. 

AUcock, H.R., Pucher, S.R., Turner, M.L., Fitzpatrick, R.J. Poly(otganophosphazenes) with poly(alkyl ether) side groups—a study of their water solubility and the swelling characteristics of their hydrogels. Macromolecules 25(21), 5573-5577 (1992). doi 10.1021/ ma00047a002... 

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