Thermosetting resin composition of a radically curable resin mixture and carbon fibre

A process for the preparation of a thermosetting resin SMC article containing a radically curable resin mixture as matrix, in which 2D-randomly distributed, discontinuous carbon fibres and other additives are present, characterized in that split, continuous carbon fibre bundles are chopped in a chopper to form packages of carbon filaments, with the carbon fibre bundles prior to chopping being provided with a sizing that is at least partially chemically bonded thereto and with a binder, which may be the same component as the sizing or different therefrom, and are added to a radically curable resin mixture consisting of:

• (a) 50-100 parts by weight of a radically curable resin that also contains a free monomer capable of copolymerising with it
• (b) 0-50 parts by weight of a shrink-resistant compound that may also contain an amount of copolymerisable free monomer, the total of (a) and (b) adding up to 100,
• as well as optionally an amount of filler, the binder's solubility at room temperature in the copolymerisable free monomer that is present amounting to at least 10% by weight, and the chopped, split, continuous carbon fibre bundles being distributed 2D-randomly and homogeneously therein by either
• 1) allowing them to drop on an SMC line onto the resin mixture and covering them with the same resin mixture, or
• 2) adding them to the resin mixture in a gap between two counter-rotating rolls followed by an impregnation step in a compacting unit or in a mixing apparatus.