Binary Immiscible Blends

Figure 1 Various phase configurations upon the extrusion of binary immiscible blend.

The mechanism and the parameters that control the droplet formation in a binary immiscible blend have been discussed in the preceding section. The size of the dispersed phase in a polymer blend is measured on images observed by microscopy. For well-mixed... 

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... 

Chen et al. [67,68] further extended the study of binary blends of ESI over the full range of copolymer styrene contents for both amorphous and semicrystalline blend components. The transition from miscible to immiscible blend behavior and the determination of upper critical solution temperature (UCST) for blends could be uniquely evaluated by atomic force microscopy (AFM) techniques via the small but significant modulus differences between the respective ESI used as blend components. The effects of molecular weight and molecular weight distribution on blend miscibility were also described. 

We begin in Section 9.2 with the morphology in binary blends of iPP and various rubbery olefin copolymers where we remark the interrelation between the miscibility and dynamic mechanical properties. Section 9.3 describes the molecular orientation behavior under tensile deformation of iPP-based blends, and we compare the differences in deformation behavior between miscible and immiscible blends. Section 9.4 contains the solidification process in iPP-based blends where the effects of miscibility in the molten state on the crystallization of iPP matrix are discussed. 

The morphological feature is in accordance with that of binary blends of iPP and true diblock iPP-b-EPR copolymers (63). For the immiscible blends showing phase separation, the EP domains have no ability to affect the lamellar or crystalline morphology of iPP. It follows that the strength of iPP lamellae is essentially independent of the addition of EP copolymers although the magnitude of bulk stress is reduced by the addition of EP copolymers with a lower modulus. 

Theoretical Aspects of the Interface 4.2.1 Binary Immiscible Polymer Blends... 

Ersoy O.G. andNugay N. (2003)Eflfectof inorganic filler phase on mechanical and morphological properties of binary immiscible polymer blends. Polym. Bull., 49, 465. 

Bitinis et developed for the first time a novel and industrially scalable PLA-NR blend prepared by melt mixing blends at 5,10 and 20 wt% of natural rubber to analyze the effect of the NR concentration on the blend morphology. Figure 7.5 shows SEM micrographs of the blends fracture surfaces where it is observed that the size of the rubber particles is similar for 5 and 10 wt% but increases for the blend at 20 wt% from 1.15 to 2.00 pm. In general, in an immiscible binary polymer blend, the size of the dispersed phase increases as a function of the concentration of the minor phase in the blend, due to coalescence phenomena. ... 

Estridge CE, Jayaraman A Diblock copolymer grafted particles as compatibilizers for immiscible binary homopolymer blends, CS Macro Lett 4 155—159, 2015. 

When investigating a binary polymer blend system, if the polymer mixture is quenched into an immiscible state then the stable blend will separate into A-rich and B-rich domains, and coarsen with time. In the present study, the system was assumed to be diffusion-controlled and there was no predominant dynamic mass flow. Rather, the composition profile was determined by the free energy minimization, as stated above. 

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