Dispersed rubbery phase function

The optimum morphology is another property necessary for good impact strengths of two-phase polymer systems. According to a theory that attributes improved impact resistance to the presence of rubbery particles, it is necessary to obtain a solid dispersion made of rubber particles of 1000-2000 nm in diameter within the glassy polymer matrix, as shown in Fig. 3.4 [44]. On the other hand, another theory assumes that the rubbery modifier functions as a continuous lattice-like phase having a honeycomb structure [45-47]. If the... 

By replacing EPR with a functionalized EPR the impact properties increase (see Fig. 24, curves C and D) and the morphology of the fractured surfaces change drastically as can be readily seen from Figs. 25c and 25d. In both cases there seems to be evidence of rubbery domains finely dispersed and well embedded in the PBT matrix. As a matter of fact the dispersed phase is barely visible. 

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