How do you calculate volumetric swelling?
and weigh the bag and then calculate the percentage of swelling through the following formula: (w2-w1)/(w1) % w1= weight of the polymer (Before swelling) w2= weight of the polymer (After swelling)
How do you calculate the hydrogels swell ratio?
The swelling ratio is defined as the difference between the initial weight of dry microgel and the weight of fully swollen gel divided by the initial weight of dry gel.
What is swelling of polymer?
The swelling is defined as a penetration of a solvent into the polymer network that causes an abrupt change in the volume (Gugliuzza and Drioli 2007), moving the boundary from unsolvated glassy region to solvated and expanding rubbery domain.
How do you calculate swelling factor?
Calculating the percentage change in height from the wet soil to the dry will give you a measure of the swell factor of the soil. For example, if the dry soil was 1 inch high and the wet soil is 1.54 inches high, divide 1 by 1.54 and multiply by 100 to get a 65 percent swell factor.
How is polymer swelling measured?
Polymer swelling can be analysed by the Flory-Rehner equation which shows how the swelling is related to the MWt of chains between crosslinks – with larger values allowing more swelling. The swelling is shown as a ratio of volumes which is identical to 1/φ2 which is the concentration of polymer in the swollen gel.
What is swelling index?
The free-swelling index (FSI) is a measure of the increase in volume of coal when heated under specified conditions (ASTM D720; ISO 335).
What is swelling in chemistry?
The swelling process is, by definition, an increase in the volume of a gel or solid connected with the uptake of a liquid or gas .
What is degree of crosslinking?
The degree of crosslinking that occurs is determined by the percentage of polymer chains that are interconnected in this network, or in other words, the density of the gel component. Higher crosslink density is the result of more linkages per length of polymer chain, resulting in larger property changes.
What is a swell factor?
The swell factor of soil is the amount of volume increase from the undisturbed (BCY) to the excavated (LCY) state due to the air pockets (fluff) created. Swelling pressure is the pressure that the expansive soil exerts if it is not allowed to swell or if the soil volume change is arrested.
Why do we calculate swelling index?
The swell index test procedure is used to determine the general swelling characteristics of bentonite clay. The Swell Index test has not been demonstrated to have a proportional correlation to hydraulic properties, a high swell is considered by most to be a good indicator of bentonite quality.