Swelling mechanism

Chatteijee, A. 2005. Application of localized reactivity index in combination with periodic DFT calculation to rationalize the swelling mechanism of clay type inorganic material. J. Chem. Sci. 117 533-539. 

In order to achieve near-zero-order release from the matrix, a unique geometry, a specific nonuniform initial concentration profile, and/or a combined diffusion/erosion/swelling mechanism provide theoretical basis for such an approach. 

The swelling mechanism is well established in rubbers (Flory, 1943). The expansion force generated by the solvent penetration is equilibrated by the entropic force linked to chain stretching. Little is known, in contrast, for the case of glassy polymers where plasticization effects are not sufficient to induce a devitrification. Swelling can be defined by... 

Osmosis can also take place in gels and constitutes an important swelling mechanism. 

Shomer, I., Frenkel, H., and Polinger, C. (1991). The existence of a diffuse electric double layer at cellulose fibril surfaces and its role in the swelling mechanism of parenchyma plant cell walls. Carbohydr. Polym. 16 199-210. 

The swelling mechanism of bentonite results from the unique microstructure and its net negative charge (Low 1987). 

It is assumed that cement paste plays a role of semi-permeable membrane which is impermeable for the silicate anions formed as a result of reaction. Some authors postulate that this semi-permeable membrane is composed of sodium and potassium sUicates gel formed during reaction. A concentration gradient appears and linked with him the osmotic pressure. Recently, the difference in discussions of swelling mechanism, attributed to the sorption of water or to the osmotic pressure, became insignificant. There is a view that sodium and potassium ions can diffuse through the semi-permeable membrane more easily than the calcium ions. 

Keywords Hybrid composites, lignocelluloses fibers, water absorption, thickness swelling, mechanical properties, acoustic properties, SEM... 

The bulk of clay soils are able to grow in volume, i.e., to swell. For a long time, it was believed that swelling mechanism is based on the process of growing thickness and increasing wedging pressure of hydrate films on the contacts between particles that lead to increasing distance between particles... 

V. F. Rosovizky, M. Ilavsky, J. Hrouz, K. Dusek, and Yu. S. Lipatov, Viscoelastic Behavior of Interpenetrating Networks of Polyurethane and Polyurethane Acrylate, /. AppL Polym. ScL 24, 1007 (1979). SINs of polyurethane diacrylate and polyurethane. Swelling, mechanical, and optical properties. Interfacial layer interpretation. 

Type Morphology Type of absorbed water Major swelling mechanism Swelling rate Application... 

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