Effect on phase morphology

Figure 10.11. Schematics of skin-core effect on phase morphology in injection molded part.

Setua, D. K. and White, J. L., Flow visualization of the influence of compatibilizing agents on the mixing of elastomer blends and the effect on phase morphology, Polym. Eng. Sci. i/ 1742 (1991). 

Most important, of course, are mixing energy and particularly shear. Also very important are melt viscosities of the two polymers, and particularly their viscosity ratio. Processing temperature has a variety of effects. Crystallization is a primary cause of phase separation, not only in single polymers but also in polymer blends. Stretch orientation has major effects on phase morphology. And demixing/coalescence/anneal-ing effects can sometimes reverse these processes. 

Water Absorption Effects on Phase Morphology of the Cored Matrix... 

The viscoelastic effects on the morphology and dynamics of microphase separation of diblock copolymers was simulated by Huo et al. [ 126] based on Tanaka s viscoelastic model [127] in the presence and absence of additional thermal noise. Their results indicate that for

bulk modulus of both blocks, the area fraction of the A-rich phase remains constant during the microphase separation process. For each block randomly oriented lamellae are preferred. 

Experimental conditions of temperature and pressure were chosen in order to avoid liquid phase segregation. The temperature has a negligible effect on the morphology and dimension of the powders obtained therefore, its value was selected to avoid the polymer degradation and to shorten the drying time. 

We have demonstrated the effects of temperature fields on deposit characteristics. The temperature distribution of field B is more uniform than that of field A. The temperature fields have important effect on the morphologies, phases, microstructute and compositions of deposits. Under the temperature field A, the morphologies were crystalline-like, the boron concentration was 87.11 at.%, the phase of deposit was B13C2 according to XRD and TEM examinations. Under the temperature field B, the morphologies were cauliflower-like, the boron concentration was 75.34 at.%, the phase of deposit was amorphous... 

This vividly illustrates that the ambient oxygen potential in the vicinity of an oxide phase has profound effect on its morphological features, which could be tailored to accentuate the sensing behaviour of a potential semiconducting oxide. 

Nanocomposite technology using small amounts of silicate layers can lead to improved properties of thermoplastic elastomers with or without conventional fillers such as carbon black, talc, etc. Mallick et al. [305] investigated the effect of EPR-g-M A, nanoclay and a combination of the two on phase morphology and the properties of (70/30w/w) nylon 6/EPR blends prepared by the melt-processing technique. They found that the number average domain diameter (Dn) of the dispersed EPR phase in the blend decreased in the presence of EPR-g-MA and clay. This observation indicated that nanoclay could be used as an effective compatibilizer in nylon 6/EPR blend. X-ray diffraction study and TEM analysis of the blend/clay nanocomposites revealed the delaminated clay morphology and preferential location of the exfoliated clay platelets in nylon 6 phase. 

Chakrit, C. B., Sauvarop, L., and Jarunee, T. 2003. Effects of fillers, maleated ethylene propylene diene. Diene rubber, and maleated ethylene octene copolymer on phase morphology and oil resistance in natural rubber/nitrile rubber blends, lournal of Avvlied Polymer Science 89 1156-1162. 

Huang W, Shen J and Chen X (2003) Effect of composition on phase morphology and mechanical properties of PP/PA66 in situ composites via extrusion-drawing-injection method, J Mater Sci 38 541-547. 

The species present in solution can have a dramatic effect on the morphology of the phase formed. This is illustrated in Figure 1.7 by SEM photomicrographs comparing ZnC204-2H20 formed by reacting a Zn nitrate solution with either... 

Recently, numerous research groups have shown that nanofillers can have dramatic effects on the morphology and properties of either rubber- or thermoplastic-modified epoxy systems [92-95]. Although such rheology studies are still in progress, it is expected that any differences in viscoelastic behavior would further influence the phase separation process, and so have serious effects on the rheological behavior. 

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