Rheological properties of SPS

Hong et al. [42] studied the effect of SEBS (LMW-SEBS with molecular weight 50000 and HMW-SEBS with molecular weight 175000) on the morphological, mechanical and rheological properties of sPS/EPR immiscible blends (80 20 wt%), melted at 300 °C for 15 min and injection molded. In the binary blend, SEM showed the presence of large domains well separated at the interface. With the compatibilizer, the dispersion of EPR becomes narrow and... 

Figure 20.10 Impact strength vs content of SEBS for sPS/EPR blends compatibi-lized with LMW-SEBS (circles) and HMW-SEBS (squares). Reprinted from Polymer, vol. 41, Hong, B. K., Jo, W. H., Effects of molecular weight of SEBS triblock copolymer on the morphology, impact strength, and rheological properties of sPS/EPR-rubber blends p. 2069, Copyright 2000, with permission from Elsevier Science...

Figure 20.9 Dynamic rheological properties of SPS/OPS nanocomposites at 280 °C. (a) Storage moduli and (b) loss moduli. In the nanocomposites, the added amount of organoclay was 3wt %. Reprinted with permission from Reference 11. Copyright (2004), with permission from Elsevier.

The precise synthesis by homogeneous catalysts created a new polymer, syndiotactic polystyrene (SPS), in 1985. SPS is categorized as an engineering plastic based on its performance. Since the discovery of SPS, many studies have been done to characterize and understand the nature of SPS. In this chapter, the properties of SPS are presented in terms of rheological, mechanical, and electrical properties. 

S. Geresh, I. Adin, E. Yarmolinsky, and M. Karpasas, Characterization of the extracellular polysaccharide of Porphyridium sp. Molecular weight determination and rheological properties, Carbohydr. Polym., 50 (2002) 183-189. 

Attempts to restrict the definition of SPs have been made. The most restrictive definition was proposed by Meijer and coworkers [2] to regard SPs as only those systems exhibiting chainlike behavior in diluted solutions. Such a definition is of interest since linear SPs do have peculiar properties (e.g., rheological ones) that widen possible applications of conventional polymers. However, a significant degree of supramolecular polymerization (DP) may not occur in dilute solutions while novel properties may appear in concentrated phases or in the bulk. Moreover, a less restrictive definition of SPs may highlight important features of supramolecular polymer chemistry better, in particular the use of approaches that cut across traditional boundaries between colloid, polymer, and solid-state science. 

The possibility of a synergistic combination of properties for SPS/nylon blends has been recognized, and, therefore, the structural and physical properties [46] as well as the morphology and mechanical properties [47] of PA 6,6 (nylon 6,6)/SPS blends have been the subject of two research articles. Below is a suimnary of the mechanical properties, rheological properties, moisture response, dimensional stability, USCAR test results, and solvent resistance of SPS/nylon blends that make these blends attractive for some applications, such... 

The comprehensive section on properties, processing, and appUcation of SPS discusses the rheological, mechanical, and other properties of this polymer... 

PPE (30)/sPS (70VS-IPO (0-25)/ SEES (0-20)/SEBS-g-MA ( 0-20) TSE/SEM/rheology/DMA/DSC/mechanical properties/effect of mixing protocol Choi et al. 1999... 

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