Morphological stability, interfacial tension, and dual-phase continuity in polystyrene-polyethylene blends

✍ Scribed by Nafaa Mekhilef; Basil D. Favis; Pierre J. Carreau

• Book ID: 102657062
• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 931 KB
• Volume: 35
• Category: Article
• ISSN: 0887-6266
• DOI: 10.1002/(sici)1099-0488(19970130)35:2<293::aid-polb7>3.0.co;2-t

✦ Synopsis

The morphological stability of polystyrene high-density polyethylene (PS/PE) blend is investigated in the region of dual-phase continuity. The effect of the addition of a triblock SEBS copolymer to the blends on the stability of these morphologies, is examined. The results show that the morphology of the unmodified blends changes from cocontinuous to droplet matrix for PS-rich blends whereas the morphology of a 50/50 blend maintains continuity but coarsened significantly upon annealing at 200ЊC. In the presence of the copolymer, these morphologies are much more stable. Selective solvent extraction of polystyrene in di-ethyl ether reveals that the level of PS continuity in the 50/50 blend is higher for the unmodified system than for the modified one. Upon annealing, the level of PS continuity significantly increases for the unmodified 50/50 PS/PE blend. The effect of the copolymer content in the blend on the interfacial tension between the two components is also investigated using the breaking thread method. The interfacial tension is found to be reduced from 5.6 to 1.1 mN/m by the addition of 20 parts of the copolymer to the blend. ᭧ 1997