The paper presents a numerical and experimental approach to quantify the effects of local thermal history on the crystallization process and final morphological characteristics of semicrystalline polymers during quiescent cooling and solidification in transient conditions. A numerical finite-difference implicit scheme is used to simulate the progress of crystallization in actual thermal transients using the simple Avrami equation, which should strictly hold only in isothermal conditions. The polymer used is a commercial Poly Propylene, marked i-PPT30G. Variable thermophysical properties and crystallization parameters are included in the model, taking into account different operating conditions and materials confining the polymer specimen. The reliability of the approach is proved by comparing numerical and experimental results, for cooling rates up to 5K/sec. A good overall agreement is achieved, with maximum deviations between experimental and calculated temperture profiles of 4K.
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