Polymer composition with filler, its method of preparation and use

A composition comprising:

• A) agglomerated spherical particles P1 comprising:
• i) (meth)acrylic copolymer (A1) or a mixture of two (meth)acrylic copolymers (A1a) and (A1b) comprising at least 50 wt % of polymeric units coming from methyl methacrylate, and
• ii) particles of filler (F) or a mixture of particles of two fillers (F1) and (F2), wherein (F), (F1), and (F2) are mineral filler selected from the group consisting of precipitated calcium carbonate (PCC), grinded natural calcium carbonate (GCC) and nanosized particles of precipitated calcium carbonate (NPCC),
• B) halogen containing thermoplastic polymer, and
• C) filler (F) or said mixture of two fillers (F1) and (F2)
• wherein the glass transition temperature Tg of the (meth)acrylic copolymer (A1) or the mixture of two (meth)acrylic copolymers (A1a) and (A1b) is between 70° C. and 105° C., and the quantity of the filler F or the mixture of two fillers (F1) and (F2) is between 1 phr and 250 phr relative to the halogen containing thermoplastic polymer, and the molecular weight Mw of the (meth)acrylic copolymer (A1) or the two (meth)acrylic copolymers (A1a) and (A1b) comprising at least 50 wt % of polymeric units coming from methyl methacrylate is at least 300,000 g/mol,
• wherein said composition comprises between 0.15 phr and 9 phr of the (meth)acrylic copolymer (A1) or the mixture of two (meth)acrylic copolymers (A1a) and (A1b) relative to the halogen containing thermoplastic polymer, such that
• part of the filler (F) or part of the mixture of two fillers (F1) and (F2) is added to (meth)acrylic copolymer (A1) or the mixture of two (meth)acrylic copolymers (A1a) and (A1b) and the other part of the filler (F) or the other part of the mixture of two fillers (F1) and (F2) is added to the composition either apart or already with halogen containing thermoplastic polymer.