PROCESS FOR POLYMERIZATION IN THE PRESENCE OF NANOPARTICLES OF A MINERAL FILLER FOR THE ATTAINMENT OF POLYMER NANOCOMPOSITES, AND A POLYMER NANOCOMPOSITE

摘要

The present invention refers to a process for the preparation of high performance polymer nanocomposites by means of an in situ continuous or batch polymerization process. More specifically, in this process, the sheet-like (layered) or spherical-like mineral filler is previously swollen with a swelling agent consisting in a saturated or unsaturated hydrocarbon or a polar or vinylic organic compound, in liquid state or near the critical point or in supercritical state, in a stirred continuous flow or batch type reactor, prior to being introduced into a polymerization reactor. The swelling agent is subjected to an endoenthalpic or isoenthalpic phase change upon being mixed with the mineral filler, in order to exfoliate and disperse the same at the nanometric level prior to the polymerization. By means of this process, mineral filler nanoparticles are incorporated and distributed homogeneously throughout the polymer matrix during the polymerization step, allowing the obtainment of a high performance polymer nanocomposite. The present invention further refers to polymer nanocomposites exhibiting differentiated properties compared with the properties of the traditional composites, such as, for example, improved mechanical and barrier properties, enhanced chemical and thermal strength and further, in case of comprising a conductive sheet-like (layered) filler, to the obtainment of a thermally and electrically conductive polymer composite.