Abstract: A polymeric dispersant having a low T.sub.g polymer component, e.g. polybutadiene, and a pendant silylated group with hydrolysable groups capable of associating with and dispersing. finely divided inorganic fillers. Curable compositions containing the polymeric dispersant can be cured into composite materials having improved resistance to stress induced by thermal cycling.

Abstract: A polymeric dispersant having a low T.sub.g polymer component, e.g. polybutadiene, and a pendant silylated group with hydrolyzable groups capable of associating with and dispersing finely divided inorganic fillers. Curable compositions containing the polymeric dispersant can be cured into composite materials having improved resistance to stress induced by thermal cycling.

Abstract: Highly filled, curable compositions containing a curable liquid, e.g. methyl methacrylate; 20 to 80% by weight of a finely divided inorganic filler of defined particle size, e.g. silica; a functionalized polymer containing a low Tg component which is soluble in the curable liquid, e.g. a functionalized vinyl aromatic/conjugated diene block copolymer; and other components which diperse the filler in the curable liquid and couple the filler to the matrix can be used to produce cured composites which show improved resistance to stress induced by thermal cycling.

Abstract: Highly filled, curable compositions containing a curable liquid, e.g. methyl methacrylate; 20 to 80% by weight of a finely divided inorganic filler of defined particle size, e.g. silica; a non-functionalized polymer containing a low Tg component which is soluble in the curable liquid, e.g. a non-functionalized vinyl aromatic/conjugated diene block copolymer; and other components which diperse the filler in the curable liquid and couple the filler to the matrix can be used to produce cured composites which show improved resistance to stress induced by thermal cycling.

Abstract: A fluid, highly filled, curable composition comprising an organic liquid which is polymerisable to form a solid polymer without the formation of elimination products and which is based on methyl methacrylate, 20 to 70% by volume of finely divided inorganic filler particles, at least 1% by volume of these being in the form of particles having a diameter of at least 30 microns, with the proviso that when the maximum particle size of such particles is 150 microns they are present at a concentration of between 20% and 70% by volume and when particles are present having a size of greater than 150 micron they are present at a concentration of at least 1% but preferably not exceeding 30% by volume and from 0.05 to 5.0% by weight of the total composition, of an organophilic, surface modified clay having a particle surface area of at least 100 m.sup.2 /g.