| abstract |
The invention relates to thermoplastic compositions comprising a polymer matrix and an additive for modifying the rheological behaviour of the molten matrix. The aim is to find an additive, preferably an unreactive additive, which is dispersible in the matrix and capable of affording a good compromise of rheological properties/mechanical properties. According to the invention, the additive is a hyperbranched polymer functionalized with radicals R2 of the type such as: substituted or unsubstituted hydrocarbon, of the silicone, linear or branched alkyl, aromatic, arylalkyl, alkylaryl or cycloaliphatic type, which may comprise one or more unsaturations and/or one or more hetero atoms. Hyperbranched polymers that result in the composition in a reduction in the molar mass of the matrix M of greater than or equal to 7% relative to a control composition comprising a matrix M and free of hyperbranched polymer additive(s), the mass measurement preferably being performed according to a given protocol P are preferably excluded. Applications: moulding, extrusion, technical plastics, yarns and fibres. |