We wish to exploit the unique capability of Nimrod to move forward the long standing issue of the way in which long chain polymers crystallise. For synthetic polymers there are two key length scales: the first involves the thin (10nm) lamellar crystal and the second is the regular local chain conformation (0.02nm - 1nm). The ability to obtain scattering data over an extensive Q range simultaneously brings new possibilities to this long standing problem and eliminates ambiguities present in the alternative approaches. We will use neutron scattering to follow the transformation pathways of these two length scales. We will tightly couple the scattering data to computational molecular modelling procedures developed at Reading to extract quantitative parameters which describe the reorganisation of the polymer chains prior to- and during crystallisation over these two length scales.