The bulk polymerisation of epsilon-caprolactone initiated by tetrapropoxy titanium was investigated in a co-rotating twin screw extruder. The process dynamic modelling, based on pressure measurements, was achieved via a combination of rheological modelling coupled with residence time distribution modelling. The former was deduced from equations which characterise the flow inside the die and the rheological behaviour of the melt polymer. The latter was determined with an in-line Ultra-Violet fluorescence method. An approach for the process regulation by the way of internal model control has given good results in simulation. However, the large response time to the control, relative to the process dynamic, constitutes a limiting factor for experimental control of the process.