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an abnormal enlargement of a bodily structure or part, esp as the result of injury



an increase in volume of solid bodies caused by their absorption of liquids or vapors from the environment. The capacity to swell is a characteristic property of bodies consisting of macromolecular compounds (polymers). Swelling is caused by diffusion processes, which are usually accompanied by solvation (the binding of a low-molecular-weight substance by a polymer).

A distinction is made between limited and unlimited swelling. In the first case the macromolecules are bonded fairly strongly, and swelling stops after having reached a certain limit. The swelled body retains its shape and a distinct boundary with the liquid phase. In the second case, mutual diffusion of the solvent and the polymer gradually leads to the disappearance of the interphase boundary between the swelling body and the liquid. Such swelling culminates in complete dissolution of the polymer. For example, limited swelling is exhibited by gel-like ion-exchange resins in water and by vulcanized rubber in benzene; unlimited swelling is exhibited by all polymers that are soluble in a particular solvent. In some cases, such as the gelatin-water system, limited swelling gives way to unlimited swelling with increasing temperature. Swelling is also a property of some minerals with a lamellar crystal lattice—for example, the montmorillonites. Upon swelling in water, such materials may undergo spontaneous dispersion, leading to the formation of highly disperse colloidal systems.

Swelling has wide use in industry and in everyday life. It frequently accompanies bonding of polymer materials, processing of polymers to produce various articles, production of rubber adhesives, and other processes, such as preparation of many foods and many natural processes (germination of seeds and spores).


Tager, A. A. Fizikokhimiia polimerov. 2nd ed. Moscow, 1968. Page 314.
Voiutskii, S. S. Kurs kolloidnoi khimii. Moscow, 1964. Page 482.



The volume increase caused by wetting, absorption of moisture, or chemical changes.
References in periodicals archive ?
The sides of the neck/throat area is perhaps most commonly where people notice their glands swelling, but it's also common to spot swollen lymph glands in the armpits and groin.
A 16-year-old boy presented with dyspnea and a 2-day history of bilateral parotid and submandibular swelling.
The swelling behaviors of superabsorbents in various solutions have been investigated by many researchers.
Hence, while the extraction processes can influence the thermodynamics of swelling processes (by changing solvent activity), there is not an experimental measurement difficulty caused by significant mass loss during swelling of these materials, if the solvent is changed so as to keep the concentration of extractables low.
We report a case of fulminant Supraglottitis with dramatic external cervical swelling due to associated cellulitis.
Since the ethmoid sinuses are near the tear ducts in the corner of the eyes, inflammation of these cavities often causes swelling of the eyelids and tissues around the eyes, and pain between the eyes.
The purpose of this article is to investigate geometrical parameters that influence extrudate swell, and to determine the simultaneous effects of swelling and drawing on the shape of profiles.
Swelling and shrinking of wood and wood-based products present perhaps the most vexing technological problems and design/utilization challenges for users and manufacturers of wood and wood products and for the ultimate consumers of these products.
Four swelling media were prepared for the swelling experiments.
Stay like this for about 20 minutes and you will find most of the swelling will have gone.
Examination revealed a smooth, translucent swelling in the skin over the right parotid gland (figure 1).
The solvent swelling is the simplest method to characterize the macromolecular organic structure of coal and to gain insight into geochemical process of maturation.