Patent ID: 8278382

Claim:
A method of preparing a transparent polymer material, said method comprising the steps of, in any order: i) mixing: mineral nanoparticles having a form factor strictly greater than 1.0; and a polymer matrix comprising a quantity of at least 80% by weight of a polycarbonate (PC) first thermoplastic polymer and of a second transparent thermoplastic polymer other than the first thermoplastic polymer; in order to obtain a mixture; and ii) heating the polymer matrix to the molten state, on its own or in the mixture; in order to obtain the transparent polymer material, the mixture of step i) comprising a quantity of mineral nanoparticles having a form factor strictly greater than 1.0 that is strictly less than 5% by weight, and step i) not involving mineral nanoparticles in the form of a premixture obtained with a thermoplastic polymer in the molten state selected from the group consisting of polycarbonate (PC), polystyrene (PS), and polymethyl methacrylate (PMMA).