The invention relates to a composition containing, in relation to the total weight of said composition, A) between 50.0% by weight and 99.5% by weight of at least one (meth)acrylate (co)polymer and B) between 0.5% by weight and 50.0% by weight of at least one copolymer, obtained by the polymerisation of a monomer mixture consisting of i. between 70% by weight and 92% by weight of a vinyl aromatic monomer and ii. between 8% by weight and 30% by weight of acryl nitrile or methacryl nitrile or mixtures thereof iii. between 0% by weight and 22% by weight of at least one other monomer, the composition having at 50° C. a ΔE of less than 0.15, ΔE being defined according to the relationship (1): (1) in which ΔL*: the modification of the colour co-ordinates L* compared with the colour co-ordinates L* at 23° C., Δa*: the modification of the colour co-ordinates a* compared with the colour co-ordinates a* at 23° C., Δb*: the modification of the colour co-ordinates b* compared to the colour co-ordinates b* at 23° C., and the composition contains at least one (meth)acrylate (co)polymer a) with a solution viscosity in chloroform at 25° C. (ISO 1628 part 6) greater than 55 ml/g. The moulded bodies that can be obtained from the composition are characterised in particular by improved stress cracking resistance and are suitable in particular for use in coatings, paints or films.