PP-nylon system

The dependence of c,y/ m,y on fiber volume fraction for the PP-nylon system is linear as shown in Figure 1. A least-squares fit of these data gives the relationship,... 

In contrast to the retarded yielding behavior exhibited by the PP-nylon system, the PP-glass fiber system undergoes the expected reduction in composite yield elongation. Figure 2 shows that the data for the PP-glass fiber system follow a modified Nielsen prediction as follows ... 

The PP-nylon system can be treated similarly. If the debonded region between the fiber and the matrix is viewed as an assembly of contiguous voids but having a volume fraction corresponding to a hypothetical cylinder (fiber) surrounding the voids, the modified form of Kemer s expression (7) for foams and polyblends can be shown to give a result in excellent agreement with Equation 2. 

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