Effect of Method of Preparation on Molecular Packing of TMPC/PS Blends

✍ Scribed by Mansour, Ashraf A.; Madbouly, Samy A.; Höhne, Günther; Dollhopf, Walter

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 389 KB
• Volume: 42
• Category: Article
• ISSN: 0959-8103
• DOI: 10.1002/(sici)1097-0126(199702)42:2<143::aid-pi598>3.0.co;2-u

✦ Synopsis

Dielectric and di †erential scanning calorimetry measurements of polystyrene/tetramethyl polycarbonate (PS/TMPC) blends have been carried out for two series of samples prepared by a melt mixing method, using a Brabender, and a solvent casting method using methylene chloride. The dielectric measurements of the samples were carried out over wide ranges of temperature (50È 220¡C) and frequency (10~2È105 Hz). The composition ratios of the samples measured were 12É5, 25, 50, 75 and 87É5 wt% TMPC for solvent casting and 10, 25, 40, 50 and 60 wt% TMPC for melt mixing. It has been found that melt mixing under the conditions used produces compatible blends for all the composition ratios measured without causing any pronounced degradation. The glass transition temperatures and dielectric relaxation behaviour of the blends prepared by the di †erent methods showed di †erences in molecular packing and dynamics. The results obtained could be attributed to a variation in the size of structural units responsible for compatibility, which depended on the method of preparation.