Final shrinkage coefficient

The softened or melted thermoplastic is forced into a mould cavity, and then cooled to solidify it and acquire its final performances. Apart from a coefficient of shrinkage and possibly warpage, the part has the shape of the cavity. 

As with the thin-film method it is difficult to define concentration in the final monolith because of the shrinkage that occurs during aging. Potential step amperometric methods or simultaneous equations can be used to overcome these problems, and self-consistent values for the diffusion coefficients can be obtained. An excellent treatment of both methods of solving for diffusion can be found in the paper by Cox et al. (153). As noted by the authors it is important to keep in mind that diffusion coefficients obtained in this manner cannot be solely attributed to the physical exchange of redox molecules, since electron... 

Mica filled compounds give low shrinkage and warpage after moulding and the final compounds have a low coefficient of expansion. Mica is unsurpassed in its ability to reduce warpage induced by... 

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