Improved composite fibers, and structural materials mixed with the improved composite fibers, are produced by an improved process that vertically texturizes and impregnates resin into the fibers without introducing any substantial amount of microbubbles in the resin. By using vertical impregnation and twisting of fiber strands with specific viscosity control, stronger composite fibers, in which substantially no microbubbles are trapped, are produced with improved tensile strength and lower variance in tensile strength, for use in strengthening structural concrete and other structural materials.

Improved composite fibers, and structural materials mixed with the improved composite fibers, are produced by an improved process that vertically texturizes and impregnates resin into the fibers without introducing any substantial amount of microbubbles in the resin. By using vertical impregnation and twisting of fiber strands with specific viscosity control, stronger composite fibers, in which substantially no microbubbles are trapped, are produced with improved tensile strength and lower variance in tensile strength, for use in strengthening structural concrete and other structural materials.

Improved composite fibers, and structural materials mixed with the improved composite fibers, are produced by an improved process that vertically texturizes and impregnates resin into the fibers without introducing any substantial amount of microbubbles in the resin. By using vertical impregnation and twisting of fiber strands with specific viscosity control, stronger composite fibers, in which substantially no microbubbles are trapped, are produced with improved tensile strength and lower variance in tensile strength, for use in strengthening structural concrete and other structural materials.

Improved composite fibers, and structural materials mixed with the improved composite fibers, are produced by an improved process that vertically texturizes and impregnates resin into the fibers without introducing any substantial amount of microbubbles in the resin. By using vertical impregnation and twisting of fiber strands with specific viscosity control, stronger composite fibers, in which substantially no microbubbles are trapped, are produced with improved tensile strength and lower variance in tensile strength, for use in strengthening structural concrete and other structural materials.

Composite roofing structures can include mineral fiber roof cover boards with high concentration of mineral wool or mineral wool and perlite. The roofing structure may include: a roof cover board including a dried base mat including: 8-25% mineral wool, 40-65% perlite, 9-15% binder, 9-15% cellulosic fiber, and 0.25-2% sizing agent, all % by weight; an insulation layer; and a roofing membrane. The roof cover board is over the insulation layer, the roofing membrane is over the roof cover board. The roof cover board is attached to the insulation layer. The roofing membrane is attached to the roof cover board. Alternatively dried base mat may include: 30-70% mineral wool, 10-50% perlite, 5-15% binder, 2-20% cellulosic fiber, and 0.25-2% sizing agent. Alternatively the dried base mat may include: 60-90% mineral wool, 0-10% fiber, 0-10% perlite, 4-10% binder, 0-5% gypsum, and 0.25-2% sizing agent.

Composite roofing structures can include mineral fiber roof cover boards with high concentration of mineral wool or mineral wool and perlite. The roofing structure may include: a roof cover board including a dried base mat including: 8-25% mineral wool, 40-65% perlite, 9-15% binder, 9-15% cellulosic fiber, and 0.25-2% sizing agent, all % by weight; an insulation layer; and a roofing membrane. The roof cover board is over the insulation layer, the roofing membrane is over the roof cover board. The roof cover board is attached to the insulation layer. The roofing membrane is attached to the roof cover board. Alternatively dried base mat may include: 30-70% mineral wool, 10-50% perlite, 5-15% binder, 2-20% cellulosic fiber, and 0.25-2% sizing agent. Alternatively the dried base mat may include: 60-90% mineral wool, 0-10% fiber, 0-10% perlite, 4-10% binder, 0-5% gypsum, and 0.25-2% sizing agent.

Fibers to be added to concrete to improve its properties are coated with an alkali-insoluble polymer, to provide adhesion of the fibers to the concrete. In a further improvement, nanoparticles are dispersed in an alkali-soluble polymer coating, and this is used to coat the fibers. When the fibers are mixed into the concrete mix, the nanoparticles are dispersed throughout the concrete, avoiding problems from agglomeration of the nanoparticles if simply added to the concrete mix.

Fibers to be added to concrete to improve its properties are coated with an alkali-insoluble polymer, to provide adhesion of the fibers to the concrete. In a further improvement, nanoparticles are dispersed in an alkali-soluble polymer coating, and this is used to coat the fibers. When the fibers are mixed into the concrete mix, the nanoparticles are dispersed throughout the concrete, avoiding problems from agglomeration of the nanoparticles if simply added to the concrete mix.

A composition for a cementitious roofing tile, the composition includes a cement binder making up 10% to 20% of a total composition weight; a fine aggregate sand making up 20% to 25% of the total composition weight; an aggregate making up 12% to 20% of the total composition weight; a crushed glass making up 15% to 60% of the total composition weight; an alkali-silica reaction (ASR) suppressant; and a predetermined volume of water; the aggregate is selected from one of perlite, vermiculite, hemp, expanded clay, coco coir, shale and slate; and the fine aggregate sand has an average particle size from a minimum of 1 micron to a maximum size of 2 mm; and the crushed glass has an average particle size that ranges from 1 micron to a maximum of 5 mm.

A composite product comprising a metakaolin-based mineral polymer. The composite product has a number of applications including use as a fire resistant material, use as a thermally insulating material and use as an impact resistance material. Methods of preparing a composite product according to the present invention and a kit of parts for preparing the composite product are also disclosed.