Conception d'un montage de microfabrication pour les nanocomposites a base de resines thermoplastiques.

摘要

The introduction of nano-materials into resins field lead to the creation of the nanocomposites. Nanocomposites are similar to traditional composites; the main difference is the nanosize of one component. This creation is starting up a new revolution into the world of materials.;Creating thermoplastics based on nanocomposites is still being a new process, many calibration tests were needed to find the limits and the optimal setting for the setup. The main hurdles were directly linked to the higher viscosity of the thermoplastic resins. Because of this property, we were forced to use settings close to the limits of the setup. This choice sometimes generated leaks specially while using the 250 mum needle. Regardless of these difficulties, the module was able to produce microfilaments with a diameter of 150 mum and microfilms with a thickness of 600 mum and microscafolds with an area of 4 cm2.;Preliminary mechanical tests were performed on the microfilaments, so as to define barrier properties. An electronic microscope analysis was done to better understand mechanical results. The mechanical tests showed a drop in the performances of the microfilaments. This is might be due to the high temperature used during the process. Through microscope analysis, aggregates of the nanoclays were observed.;While comparing the barrier properties between two samples (one made by direct-write technique and the other one using a press machine) an impressive improvement becomes clear on the direct-write sample. These results represent the basis for many future works that are going to use these structures for biomedical or food industry applications.;The following report deals with a nanocomposite based on a thermoplastic resin (Polylactic acid PLA) and a nanoclay (Cloisite 30B). This nanocomposite was engineered by the Institute of Industrial Material (IMI-CNRC) using a twin screw extruder machine. The main objective of the project is to enhance the mechanical and the barrier properties by working on the orientation of nanoclay-layers. This control of the orientation is possible thanks to the shearing that is happening inside the microfabrication module. To achieve this goal, we started by designing the direct-write module for thermoplastic materials, then we made different structures like microfilaments, microfilms, and micro-scaffolds and finally we analyzed these structure's performance.