Direct determination of the rate of homogeneous spherulite initiation requires the subdivision of the melt into a large enough number of droplets so that all undesired nucleation catalysts (heterogeneities, motes, etc.) will be confined to a relatively small number of them. If the undesired heterogeneities nucleate very rapidly, the droplets free of them will freeze at a rate proportional to their volumes and the inherent (homogeneous) nucleation frequency per unit volune. In many cases, however, the time‐dependent freezing process is pseudohomogeneous, i.e., the result of concurrent homogeneous and heterogeneous (but sporadic or nearly sporadic) nucleation. A method is presented for analyzing data corresponding to this case and for determining the limits within which the droplet nucleation experiment can be expected to yield fruitful results.

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Since most droplet experiments require υ values of about 103 cm3 (radius ≅3μ) it follows that x must be of the order of 1010cm−3 in order that f0 be greater than about one third.
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