taken at a point which is not attached to the pe film the points where the paperboard primed with p 3 is attached to the pe film looks like the fig1 the paperboard with primer p 5 has also been attached partly to the pe film the picture to the right in fig1 was taken at a point where the paperboard is not attached to the pe the morphology of the primer p 5 does not significantly change during extrusion coating despite the use of corona treatment the morphology of primed p 6 changed during extrusion coating if corona treatment was used p 6 spreads on the surface of the paperboard fig1 has been taken at a point where there is no attachement to the pe probably the priming weight 0 1 g m 2 is too much because the paperboard with p 6 is not attached properly to pe the morphology of p 7 changes in extrusion coating significantly the fiber is attached to the surface of the paperboard spreads a bit and probably absorbed fig1 instead the morphology of p 8 is not significantly changed in extrusion coating fig2 the morphology of p 11 p 12 and p 13 has changed significantly during the extrusion process fig2 all of these primers are attached to the surface of the paperboard primers have spread and probably absorbed to the surface of.