Rheology and Adhesion for Medical Applications Laboratory – LERAM

The LERAM joint project (Laboratoire d’Etude de la Rhéologie et de l’Adhésion des adhésifs destinés à des applications Médicales) carries out diverse, original and exhaustive studies on the adhesion of polymer materials on body tissues. The project deals with the issue of adhesive properties on body tissues and with the elaboration of appropriate adhesives for specific applications in the medical field. For the fabrication of new products at industrial scale, the deposition of thin adhesive films on different substrates is also studied within the LERAM project via the elaboration of on-line measurement tools. These tools would help to monitor the fabrication of adhesive products in order to improve the products quality. That’s why two research topics have been developed.
First, the joint project aims at better understanding the adhesive properties of polymer materials on viscoelastic substrates and in wet conditions (like body tissues) in order to elaborate original adhesives for highly specific applications. This work draws on sound knowledge on the links between the macromolecular structure, the rheology and the adhesion of polymer materials. The models developed in rheology (more specifically in viscoelasticity) coupled with the theory of fracture of fracture mechanics constitute a powerful numerical tool to predict the mechanical behavior of materials in adhesion tests. Concerning the issue of adhesion on human skin, a first family of adhesives has been optimized and a project of industrial production has been launched in order to sell them in the market about 2020-20222. For oral tissues, the design of new copolymers and formulations containing new acids allowed to better understanding the molecular mechanisms in this very specific application.
The second research topic concerns the deposition of thin adhesive films for the fabrication of protective dressings. In order to optimize their production, studies on the deposition process have been carried out. In order to monitor this process, a prototype of on-line measurement tools has been made in the IPREM laboratory. This prototype takes the parameters of industrial process into account and, in the future, will be transferred in production lines for the URGO RID company. It will be also exploited in URGO RID as a development tool.
All these works led concrete results as well as a better understanding of complex mechanisms. The modelling of the physics behind these mechanisms will allow to building a tool of virtual formulation in the future. The continuation of the LERAM joint project is based on both research topics and will take shape in different ways: the monitoring of a PhD study (started on January 2017) on microgel assembly, the financing of one post-doctoral researcher for the study of copolymer formulations (1 year contract in 2018) and that of one research engineer for the development of the on-line measurement tool (1 year contract in 2018).
The close relationship between URGO RID and the research joint laboratory between l’Université de Pau et des Pays de l’Adour and the CNRS, IPREM-UMR 5254, established on complementary skills, has allowed advances for both of them. A follow-up comittee often meets and favors a strong dynamics. At The IPREM, a room is restricted to LERAM experiments and workers in order to keep the project confidential. Thanks to initial funding, the launch phase of the project has been fast and effective, offering real prospects. Considering the development lead times in the medical field, the continuation of the LERAM project will allow to improve the room restricted for URGO RID at the IPREM and to provide co-funding for project proposals (like for the PhD).