2.3.6. Gel Fraction and Percent Swelling

Swelling and gel fraction of 3D-printed rings was carried out in chloroform to determine the monomer incorporation and crosslink density. To determine gel fraction, rings (n = 3) were first weighed to record their initial mass at time zero (Mo) and then placed in 50 mL jars containing chloroform for one week. After one week, rings were removed and carefully cleaned with Kimwipe and the swollen mass (Ms) was recorded. The rings were subsequently air dried for three days and the dry weight (Md) was recorded. The gel fraction and degree of swelling was calculated using the following equations:

$$\text{Gel Fraction} = \frac{\text{Md}}{\text{Mo}}\tag{1}$$

$$\% \text{ Solvent update} = \frac{\text{Ms} - \text{Md}}{\text{Md}} \times 100\tag{2}$$
