undergo micro dispersion in order to assume a benign condition with respect to the mechanical properties of the solid polymer and those properties suffer if the polymer is the first to solidify on the other hand if the t m of the additive is much above 180 u00b0 c the mixture must be heated to so high a temperature to become completely fused for processing that the danger of decomposition of the polymer is increased by utilizing an additive having the preferred minimum t m of at least about 100 u00b0 c one can minimize the possibility of encountering a hysteresis effect during quenching and re heating of the mixture resulting in an apparent t c of the additive below the polymer solidification temperature notwithstanding a higher rated t m in this way solidification of the additive prior to polymer solidification is virtually ensured it is noted that t c is always lower than t m also a significant difference between the t g range of the polymer and the t m of the additive is advantageous for accurate dsc evaluation since if these values overlap discrimination in the behavior of the polymer and additive during dsc testing is less clear and evaluation more difficult with regard to the molecular weight of the additive the upper limit is not particularly critical and generally the molecular weight can range up to.