Abstract: An abrasion resistant acrylic composition comprises at least 70% w/w of the residues of at least one polmerisable acrylic monomer, 0.2-5% w/w of a finely divided compound comprising at least one oxide selected from silicon, titanium, zirconium and aluminum oxides, and 0.2-25% w/w of at least one linking compound which is miscible with said polymerisable acrylic monomer and which is capable of bonding to the surface of the oxide compound. The acrylic composition may be thermoformed while retaining its abrasion resistant surface properties.

Abstract: A multistage core-shell particle consisting of a core, a first shell and optionally a second shell, substantially free from vinylically unsaturated compounds having at least two equally reactive double bonds, wherein: (i) the core contains a first (meth)acrylic polymer, (ii) the first shell contains a low Tg polymer comprising 0 to 25% by weight of a styrenic monomer and 75 to 100% by weight of a (meth)acrylic monomer, the (meth)acrylic monomer capable of forming a homopolymer having a glass transition temperature (Tg) in the range from −75 to −5 C, and which first shell represents more than 65% by volume of the combined volume of the core and first shell; (iii) the second shell, when present, contains a second (meth)acrylic polymer which may be the same or different from the first (meth)acrylic polymer, and (iv) the core and first shell together contain from 0.5 to 1.0% by weight of a graft-crosslinker.