Rex Hjelm to Present at 9th International Conference on Polymeric Materials in Automotive PMA 2023
New Mexico Consortium scientist Rex Hjelm has been invited to present a keynote lecture at the 9th International Conference on Polymeric Materials in Automotive PMA 2023. This meeting focuses on various aspects related to plastics and rubber in the automotive industry, with the goal to present and discuss innovative approaches towards new polymer products that increasingly have a decisive influence on the design and appearance of new generation of cars.
At this meeting, a limited number of plenary lectures will be presented by invited speakers. One session is planned to consist of a few key lectures and a number of contributed lectures will be presented by either invited speakers or registered participants
Hjelm’s talk is titled, “Critical tests of tube theory through experimental verification of polymer molecular architecture response in the linear and non-linear rheological domains” and is a review of his recently published work on entangled polymer melts. This talk will provide a more practical assessments of theory than the invited talk he gave at the German Rubber meeting last Fall.
The molecular-level response to shear of entangled polymers at interfaces and in the bulk has been of interest to understand the non-linear rheological response of polymers. Hjelm’s research focuses on the molecular level response to shear strain leading non-linear rheological phenomenon, in linear and star polymers comparing the observed response to the predictions of tube theory.
In this research, he used SANS measurements of the bulk polymer response to shear in Couette geometry on melts of high molecular weight mixtures of polymers extending our previous results on interfacial responses with rheoNR measurements in cone-and-plate geometry. The results showed that tube theory captures significant aspects of the behavior of this complex system to an impressive degree. The results also showed that tweaks are needed to provide a more complete picture, providing motivation for further development of the theory.
The meeting will be held May 24-26, 2023 at the Smolenice Castle in the Slovak Republic. The website can be found at https://pma.sav.sk.