Melting and Non-Isothermal Crystalization Kinetics of Gamma Irradiated UHMWPE and UHMWPOE. Theoretical Approach, Parameters, Characterizing and Crystal Structure pp. 69-91
Authors: (Maya Staneva, Ph.Ublekov and Emmanuel Nedkov)
Abstract: The goal of the research is to apply a renewed Nedkov-Atanasov approach to γ- irradiated ultra-high molecular weight polyethylene (UHMWPE). The samples were investigated by means of Differential Scanning Calorymetry (DSC). Non-isothermal processes (crystallization and melting) were studied. The crystallization process is split into sub-stages, and for each one of them parameters, characterizing the crystalline structure were estimated: • Free energy of the folded surface: c; • Lamellar thickness: c cr L ; • Activation energy for diffusion across the the phase boundary melt – crystal: c d E ; The same parameters were calculated from the melting DSC-curves as follows: • Lamellar thickness: m cr L ; • Free energy of the folded surface: m; • Activation energy for diffusion across the phase boundary crystal-melt: m d E .