The on-line morphological development during film blowing of 2 different linear low density polyethylenes (LLDPEs) and a blend of LLDPE with low density polyethylene (LDPE) has been investigated, for the first time, using synchrotron Small Angle X-ray Scattering (SAXS). The processing conditions, blow-up ratio and take-up ratio, have been varied and the resulting lamellar thickness, linear crystallinity and orientation evolution in machine direction is obtained from a detailed analysis of SAXS data. Ex-situ SAXS and wide angle X-ray Diffraction (WAXD) confirmed the effect of molecular structure and composition on structure evolution observed in the on-line experiments. The results obtained provide a valuable set of data for the understanding of the film blowing process and can be used to extend and improve numerical model.
Troisi, E. M., van Drongelen, M., Caelers, H. J. M., Portale, G., & Peters, G. W. M. (2016). Structure evolution during film blowing: An experimental study using in-situ small angle X-ray scattering. European polymer journal, 74, 190-208. https://doi.org/10.1016/j.eurpolymj.2015.11.022