Monitoring in-situ dissolution of polystyrene-acrylonitrile (SAN) via calorimetry and spectroscopy

•Dissolution of SAN in MEK was followed by FTIR spectroscopy and calorimetry.•The enthalpy of dissolution is dominated by the glassy to rubbery transition.•The kinetic of dissolution is governed by the diffusion of solvent. Dissolution/precipitation recycling is an environmentally friendly solution that could be potentially implemented for ABS recycling. In this paper, a set of useful calorimetric, spectroscopic, and rheological techniques and methods are presented to monitor in-situ the dissolution of the ABS matrix: poly(styrene-acrylonitrile) (SAN). In line with the Hansen solubility parameters, methyl ethyl ketone (MEK) has been selected to be a suitable solvent for SAN dissolution. Thermodynamic and kinetic aspects of the dissolution process were investigated by using calorimetry and in-situ ATR-FTIR spectroscopy. Through an isoconversional method, the effective activation energy and the main steps involved in the dissolution process were determined. A rheological characterization of the solution SAN-MEK was also performed to provide further information on the rheological behavior.