Resumo

BALSAMO, V et al. Nucleation efficiency analysis of different agents in Polycaprolactone. Rev. Fac. Ing. UCV [online]. 2006, vol.21, n.3, pp.105-119. ISSN 0798-4065.

The potential nucleating effect of eight different compounds on the poly(e-caprolactone), PCL, was evaluated by means of Differential Scanning Calorimetry (DSC). From these, Boron Nitride (NB) was the best nucleating agent. In addition, the self-nucleation behavior of pure PCL as well as PCL with three nucleating agents was analyzed. At the optimal selfnucleation temperature, the NB leads to a shift of the PCL crystallization temperature to values that are even higher than those obtained in the self-nucleated PCL under the same conditions. This result indicates a nucleation efficiency higher than 100% if the scale proposed by Fillon et al., (1993) is used. On the other hand, if the maximum crystallization temperature after annealing is used for the calculations, values lower than 100% are obtained. Then, as expected, the thickest PCL lamellar crystals are better nucleating agents than NB. From these results, it can be concluded that the scale used by Fillon et al., (1993), is not the most appropriate due to the high efficiency of the NB to nucleate the PCL; therefore, it should be modified taking into account as a reference the nucleation induced by the annealed crystals of PCL.

Palavras-chave : nucleation; nucleating agent; poly (e-caprolactone e-caprolactona); Boron Nitride; self-nucleation.

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