Swelling in liquids

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. 

The rate of swelling in liquid water of an aspen flakeboard made from acetylated flakes and phenolic resin ( ) is shown in Figure 3 During the first 60 min, control boards swelled 55 percent in thickness, while the board made from flakes acetylated to 17 9 WPG swelled less than 2 percent. During 5 days of water soaking, the control boards swelled more than 66 percent, while the 17.9 WPG board swelled about 6 percent. 

Figure 3—Rate of swelling in liquid water of aspen flakeboard made from acetylated flakes. O = control + = 7 3 WPG ...

Generally, vulcanised rubber is dimensionally very stable (unless it is strained), which probably explains the lack of standard test methods for this property. In this context, thermal expansion and swelling in liquids are properties considered in their own right and not normally thought of as being measures of dimensional stability. This is a different situation to that which exists with plastics where a number of dimensional stability tests are in existence. If a measure of dimensional change is required, the appropriate dimensions of a suitable sized test piece can be measured by any of the methods mentioned in this chapter before and after an ageing treatment. 

More recently, aspen fiber was esterified with MA and PA [60]. Esterified fiber in fiberboards had reduced moisture sorption and rate of swelling in liquid water. 

Early calibration materials were often pollen since these have a very narrow size range. Arguments persist as to whether these swell in liquids or change size over time. Polymer latices are also available as calibration material. When instruments are used regularly to test a limited range of products the product itself can be used for calibration purposes. Thus a manufacturer of titanium dioxide may set aside an easily dispersed, stable sample for sample splitting and subsequent use for instrument evaluation. 

Notably, sulfonated hypercrosslinked resins readily swell in liquid methanol or ethanol, and the latter can be then replaced with hexane, without causing any coUapse of the network (see Table 16.3). We would like to emphasize here a close analogy in the behavior of dry sulfonated resins with respect to hexane and that of dry initial hypercrosslinked... 

Saunier, AUoin, E, Sanchez, J.-Y., Maniguet, L, 2004. Plasticized microporous PVdF separators for lithium ions batteries. Part 111 gel properties and irreversible modifications of PolyfvinyUdene fluoride) membranes under swelling in liquid electrolyte. J. Polym. Sci. Part B 42,2308-2317. 

The rate and extent of thiekness swelling in liquid water of fiberboards made from eontrol and aeetylated fiber are shown in Table 7.14. Both the rate and extent of swelling are greatly... 

Rate and Extent of Thickness Swelling in Liquid Water of Kenaf Fiberboards Made from Control and Acetylated Fiber and a Phenolic Resin [Resin content of boards 8%]... 

Cotton filter cloths are among the most widely used filter media. They have a limited tendency to swell in liquids and are used for the separation of neutral suspensions at temperatures up to 100°C, as well as suspensions containing acids up to 3% or alkalies with concentrations up to 10% at 15-20°C. Hydrochloric acid at 90-100°C destroys cotton fabric in about 1 hour, even at concentrations as low as 1.5%. Nitric acid has the same effect at concentrations of 2.5%, and sulfuric acid at 5%. Phosphoric acid (70%) destroys the cloth in about six days. Water and water solutions of aluminum sulfate cause cotton fabrics to undergo shrinkage. 

Chen ZH, Christensen L, Dahn JR (2004) Mechanical and electrical properties of poly (vinylidene fluoride-tetrafiuoroethylene-propylene)/super-S carbon black swelled in liquid solvent as an electrode binder for lithium-ion batteries. J Appl Polym Sci 91 2958-2965... 

Swelling in liquids is frequently used to estimate the molecular weight between effective cross-links in conventionally vulcanized elastomers. This molecular weight, is calculated from the Hory-Rehner in equation (2.3) ... 

The swelling in liquid water could be a nonrelevant value to describe the membrane behavior in fuel cells. As an example, the sulfonated polyether ketones suffer from an excessive water uptake when immersed in hquid water at elevated temperatures [110], while a high-temperature fuel eeU test over 1400 h has been performed with fully hydrated gases [2]. Therefore, the swelling in hquid water at elevated temperature is of limited value. Most of the authors prefer nowadays to determine the water uptake under defined temperature and RH conditions. Water sorption isotherms have been measured and analyzed [40,104,119]. These results confirmed the previous data since the sorption isotherms are superimposable when expressed in 2 values for different ion contents and chemical structures [40,48,49,56]. The sorption isotherms were classically analyzed as the superposition of different phenomena (Henry, clustering, dual-mode, Flory-Huggins, and BET II processes) [119]. The water sorption isotherms exhibit a distinct sorption-desorption hysteresis, which was attributed to the very low desorption process [40]. 

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