Hydrogels swelling kinetics

The swelling pattern considered above allows us to understand the peculiarities of the behavior of SAH and the effects encountered during their application. The kinetic aspects of swelling seem to be as important as the thermodynamics of this process. Therefore, we shall touch upon some problems concerning the kinetics of hydrogel swelling and deswelling. 

The complexity of the swelling kinetics of hydrogels means that only the simplest cases can be modeled quantitatively. Thus this section focuses on identification of rate-influencing phenomena and data analysis rather than the extensive theoretical modeling of the kinetic phenomena that has been done on this subject. Reviews of theoretical modeling include those by Peppas and Korsmeyer [119], Frisch [120], and Windle [121],... 

L Westman, T Lindstrom. Swelling and mechanical properties of cellulose hydrogels. IV. Kinetics of swelling in liquid water. J Appl Polym Sci 26 2561-2572, 1981. 

Swelling Kinetics of Hydrogels Hydrogels, Microporous Hydrogels, and Macroporous Hydrogels Superporous Hydrogels (SPHs)... 

Fig. 2. Swelling kinetics of 8 caffeine-loaded methyl mcthacrylate/jV.A -dimethylaminoethyl methacrylate copolymer hydrogels. ( ) pH 3, (A) pH 5. Siegel RA, Falamarzian M, Firestone BA, Moxley BC (1988) J Contr Rel 8 179. Reproduced with permission...

Akala, E. O., Kopeckova, P., and Kopecek, J. (1998), Novel pH-sensitive hydrogels with adjustable swelling kinetics, Biomaterials, 19,1037-1047. 

Katime, L Novoa, R. Zuluaga, F. Swelling kinetics and release studies of theophylline and aminophylline from acrylic acid/n-alkyl methacrylate hydrogels. Eur. Polym. J. 2001, 37, 1465-1471. 

Falamarzian, M. Varshosaz, J. The effect of structural changes on swelling kinetics of polybasic/hydrophobic pH-sensitive hydrogels. Drug. Dev. Ind. Pharm. 1998, 24, 667-669. 

Gan, D. Lyon, L.A. Tunable swelling kinetics in core-shell hydrogel nanoparticles. J. Am. Chem. Soc. 2001, 123, 7511-7517. 

The swelling kinetics of /J-lactoglobulin hydrogels showed that the increase of... 

Figure 4 Swelling kinetics of P-lactoglobulm hydrogels both in dehydrated and hydrated forms for different solvent conditions ( ) ethanol ( ) water/ethanol 50/50 (v/v) ( ) water, (O) 0.1 M NaCl (A) water/ethanol 50/50 (v/v) (hydrated gel) (A) water (hydrated gel)...

The swelling kinetics of stimuli-responsive hydrogels is described by the theory of cooperative diffusion (Sect. 3.2.2 and 3.2.3, (Tanaka and Fillmore 1979)). Besides the cooperative diffusion constant, which is specific for each solvent-polymer network combination (see Eq. (3.2.9)), the time behaviour of active hydrogel components can be as well influenced by further design-dependent aspects (Richter 2006, 2008b). 

Figure 7a shows typical swelling kinetics of HM PAAm hydrogels where the relative gel mass in water (Wrei) is plotted against the swelling time [33]. In Fig. 7b, the amount of SDS released from the gel is plotted as a function of the swelling time. As a result of the osmotic pressure of SDS counterions within the... 

Table 10.1 Porosity-related swelling kinetics of hydrogels...

Yao DK, Peng T, Feng HB, He YY. Swelling kinetics and release characteristic of cross-linked chitosan polyether polymer network (semi-lPN) hydrogels. J Polym Sci A Polym Chem 1994 32 1213-1223. 

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