(385d) The Challenges of Product Development in High-Pressure Polymerization Technology - How Simulations Can Help

Product development in high-pressure polymerization technology is a specifically demanding task. First, operation procedures from large-scale technical practice cannot be scaled down to typical lab application one to one. Second, competitive high-pressure polymerization plants operate on a scale of significant more than 100 kt/á production capacity. Both, the significant scale up as well as limitations in miniaturizing laboratory equipment are still a remarkable challenge in designing strategies for product development in high-pressure polymerization technology. The contribution will take a look on how simulation technologies can help to overcome these challenges and were actual the limitations occur.

The first target is the prediction of microstructural polymer properties from process conditions and strategy. During the recent years there has been remarkable progress. Specifically, the combination of deterministic modeling with Monte-Carlo techniques, so-called as hybrid technology, brought significant improvement with respect to detail of predicted molecular structure and limitation of computational efforts. By this the detail is sufficient for feeding rheological models and demands on computational equipment together with the speed of computation is sufficient to establish such technologies in standard research. The contribution review the current status present examples of such investigations and discuss the portability of such technologies.

With increasing insight into the polymer structure aspects of reactor operation come into focus again that have been accepted for a long time as non ideal behavior to be adapted as the impact of the correlation of process conditions in polymer microstructure had been the dominant problem. Now, as a second aspect the modeling of species none uniformly distributed along the reactor axis come into focus again and the resulting consequences. The contribution will have a look on radial distribution in high-pressure polymerization reactors together with origin and consequences of varying heat transfer in reactor tubes.

Another issue are the accessible thermo physical properties of supercritical media. For a long time their precision seemed to be sufficient as the dominant field of uncertainty was the reaction mechanism together with its kinetics. Again, progress in this field reopened the question of precise information in this field. The contribution will evaluate that current status and discuss consequences and perspectives.