Time-resolved SAXS data analysis of a lamellar two-phase polymer system by means of the correlation function
University of Bielsko-Biala, Willowa 2, Bielsko-Biała 43-309, Poland
Melting and crystallization of linear polyethylene (HDPE, high-density polyethylene) and its blends with poly(ethylene-α-olefin) copolymers has been the subject of many studies in recent years. The final properties of such polymers depend on the volume fraction of the crystalline domains as well as on their size and structure. During crystallization from quiescent melt these polymers usually form thin lamellar crystals. These lamellae are arranged in stacks, with layers of amorphous material being inserted between the crystalline lamellae. Because amorphous and crystalline layers in lamellar stacks exhibit different electron densities, the small-angle X-ray scattering (SAXS) patterns and the derived correlation functions are commonly used in polymer morphology characterization. These functions allow for determination the values of the long period (LP), the crystalline and amorphous layer thickness (lC and lA respectively) and the local volume fraction crystallinity (ΦL). ΦL can be obtained from the correlation functions in two different ways. Both methods have their own prerequisites and limitations. Moreover, application of the correlation functions requires subtraction of contribution due to electron density fluctuations and realization a number of corrections of measured intensities.
Presentation: poster at E-MRS Fall Meeting 2003, Symposium B, by Czesław Ślusarczyk
See On-line Journal of E-MRS Fall Meeting 2003
Submitted: 2003-05-14 17:14 Revised: 2009-06-08 12:55