The glass‐to‐gel transition in solvent‐swollen polystyrene networks

Glass transition temperatures have been determined for polystyrenes crosslinked with 1–10% divinylbenzene and swollen with toluene, chloroform, N , N ‐dimethylformamide, and tetrahydrofuran to as high as 0.7 weight fraction solvent. The T g ′s depend approximately on the weight fractions and the T g ′s of the components according to the empirical equation 1n T g = m 1 1n T g 1 + m 2 1n T g 2 of Pochan. The T g ′s of the networks swollen with toluene also fit approximately a quasithermodynamic equation of Karasz based on the T g ′s and the Δ C p ′s at T g of the components.