Phase separation in polystyrene crosslinked with samples of poly(dimethyl siloxane) of various chain length
✍ Scribed by Heikki Tenhu; Kari Vaahtera
- Book ID
- 103071740
- Publisher
- Elsevier Science
- Year
- 1991
- Tongue
- English
- Weight
- 460 KB
- Volume
- 27
- Category
- Article
- ISSN
- 0014-3057
No coin nor oath required. For personal study only.
✦ Synopsis
Crosslinked polystyrene (PS) has been prepared by copolymerizing styrene with bifunctional poly(dimethyl siloxane) (PDMS) derivatives. The polymers have been studied by DSC and by EPR spectroscopy using a nitroxide sond added to the polymers. According to the calorimetric data, crosslinkers with molar mass of 200 and 2000 respectively, mix with PS and change considerably its properties. EPR data show however that not only the crosslinker with molar mass of 35,000 but also that with molar mass of 2000, separate from PS and form distinct phases. In the phase separated samples, two glass transition temperatures have been observed by EPR. The size of the motional PS chain segment in various samples has been estimated by comparing the DSC and EPR data.