Research objectives and content
Final properties of manufactured semicrystalline polymers are determined by the structure developed which, in turn, depends on solidification conditions experienced during processing, where multiple driving forces determine the structure developed. The contributions of thermal history and orientation effects can in principle be separated by comparing the properties of blown films and thin model films obtained in absence of material flow and at cooling rates similar to those experienced during normal processing routes. This study will be applied to PB/Polyolefins blends where compatibility effects and after mixing morphology arise on complicating effects with respect to previous and parallel works. Two types of films will be produced differing only for the flow condition, since the model films are isotropic. Comparison of the final Structure determined on both sets of films, investigated through density, WAXD and SALS tests to monitor crystallinity, amount and type of crystalline phases and morphological texture, will yield a relationship to solidification conditions. Various samples, that differ in composition and in thermo-mechanical history, will be tested in impact and dynamic conditions to evaluate their performance and relaxation behaviour and the relationship with the structure developed. An attempt to establish such cause-effect relation will also be made for technologically relevant standard tests. Training content (objective, benefit and expected impact)
The results expected from this proposal will be of scientific and technological value as PB/polyolefins blends behaviour has not been investigated in detail so far. Scientifically, the results expected will extend the knowledge of the behaviour of polymer solification in more realistic conditions.
Links with industry / industrial relevance (22)
The group to which the candidate will be attached shares responsibility for technical market development and therefore offers exposure to the various opportunities, constraints, problems and politics of competitive commercial product marketing, in addition to the scientific and technical aspects of formulation, processing and characterization The candidate will be exposed to the broader issues relating to the fortunes of the polymer products in the Shell Chemical portfolio, since the student trainees are generally fully integrated into the work groups to which they are attached.