| Institution: | 1. National Institute of Applied Sciences, Laboratory of Macromolecular Materials (IMP/LMM), UMR CNRS 5627;2. 17, Avenue Jean Capelle, 69621 Villeurbanne Cedex, France
Institute of Polymer Research Dresden, Physical Chemistry and Physics of Polymers, Hohe Strasse 6, 01069 Dresden, Germany;3. Institute of Polymer Research Dresden, Physical Chemistry and Physics of Polymers, Hohe Strasse 6, 01069 Dresden, Germany;4. 17, Avenue Jean Capelle, 69621 Villeurbanne Cedex, France |
| Abstract: | Syndiotactic polystyrene (sPS) has to be processed at high temperatures (i.e. >290°C due to its melting point of 270°C), which approaches its degradation temperature. We aim to facilitate the processing of sPS by lowering its melt temperature and viscosity with a curable epoxy/amine model system as reactive solvent, which will result in a thermoplastic-thermoset polymer blend. As a first step we therefore investigated the melting behaviour of sPS in epoxy monomer, established its phase diagram, and investigated the crystalline form of sPS in these mixtures. DGEBA epoxy monomer is found to be a solvent for syndiotactic polystyrene at temperatures above 220°C. The DGEBA-sPS phase diagram was established by means of DSC, on the basis of crystallization and melting peaks. The form of the curve in the phase diagram indicates that DGEBA is a poor solvent for sPS. In WAXS studies of blends only the β crystalline form was detected, not the δ form, thus no sPS-DGEBA polymer-solvent compounds (clathrates) were detected. However, DGEBA can still serve as a monomer for improved processing as it depresses the crystallization temperature by 20 to 60 K upon addition of 20 to 90 wt% DGEBA respectively, while a 16 to 45 K melting peak depression can be observed by adding 20 to 90 wt% DGEBA. |
