Effect of Reinforcing Agents on Electrical Properties

For some electrical applications improvements in mechanical properties such as tensile strength of the polymer might be required, for example, impact resistant electrical plugs or housings for electrical gears. This can often be achieved by the incorporation of a reinforcing agent in the polymer formulation. Unreinforced PEEK, for example, has the electrical properties shown in Table 4.4. 

This makes the polymer very suitable for printed circuit board manufacture. However, the incorporation of 30% glass fibre into the PEEK formulation produces a pronounced improvement in tensile properties and flexural properties with some deviation in elongation properties as shown in Table 4.5. 

Similar comments will apply, for example, to PES and PA 12, which have dielectric strengths of 16 and 60 mV/m, respectively. 

For PES the incorporation of 30% carbon fibre almost donbles the impact strength from 86 to 195 MPa and increases the flexnral strength from 2.6 to 15.2%. 

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