Embodiments of the present disclosure provide an ex-situ preparation method for a composite molded body. The preparation method comprises: providing a porous support, a first component, and a second liquid component; contacting the first component with the porous support; contacting the second liquid component with the first component and/or the porous support, in which process the first component and the second liquid component do not undergo a chemical reaction, and the second liquid component remains in a liquid state; and treating the first component and the second liquid component such that the first component and the second liquid component undergo a chemical reaction to become a solid, or undergo phase transformation toughening and solidification molding. The present disclosure discloses an advanced composite material manufacturing technology, and relates to a low-cost and easy-to-operate ex-situ liquid molding preparation method. In the method, core reaction components are separated spatially, and two sub-processes of physical flow and chemical reaction are separated chronologically, thereby greatly simplifying the liquid molding technique. The “ex-situ” preparation method is applicable to liquid molding manufacture of thermosetting resins, liquid molding and toughening of thermosetting composite materials, and liquid molding manufacture of thermoplastic composite materials. By means of the “ex-situ” liquid molding, some resin materials originally unsuitable for liquid molding can be modified into liquid-moldable materials, thereby expanding the options and types of resin materials for liquid molding.

Embodiments of the present disclosure provide an ex-situ preparation method for a composite molded body. The preparation method comprises: providing a porous support, a first component, and a second liquid component; contacting the first component with the porous support; contacting the second liquid component with the first component and/or the porous support, in which process the first component and the second liquid component do not undergo a chemical reaction, and the second liquid component remains in a liquid state; and treating the first component and the second liquid component such that the first component and the second liquid component undergo a chemical reaction to become a solid, or undergo phase transformation toughening and solidification molding. The present disclosure discloses an advanced composite material manufacturing technology, and relates to a low-cost and easy-to-operate ex-situ liquid molding preparation method. In the method, core reaction components are separated spatially, and two sub-processes of physical flow and chemical reaction are separated chronologically, thereby greatly simplifying the liquid molding technique. The “ex-situ” preparation method is applicable to liquid molding manufacture of thermosetting resins, liquid molding and toughening of thermosetting composite materials, and liquid molding manufacture of thermoplastic composite materials. By means of the “ex-situ” liquid molding, some resin materials originally unsuitable for liquid molding can be modified into liquid-moldable materials, thereby expanding the options and types of resin materials for liquid molding.

Provided is a sheet molding compound which can inhibit the formation of burrs during press molding, enables a matrix resin to exhibit excellent fluidity and excellent quick curing properties during press molding, and makes it possible to obtain a fiber-reinforced composite excellent in mold release properties, mechanical characteristics, and heat resistance. The sheet molding compound of the present invention contains an epoxy resin composition and reinforcing fiber, in which a gel time of the epoxy resin composition is 30 to 140 seconds at 140° C., a temperature at the start of curing reaction of the epoxy resin composition is 70° C. to 115° C., and when b1 represents a viscosity of the epoxy resin composition measured at 30° C. 7 days after the preparation of the composition, and b2 represents a viscosity of the epoxy resin composition measured at 30° C. 14 days after the preparation of the composition, b1 and b2 satisfy b2/b1≤5.

Provided is a sheet molding compound which can inhibit the formation of burrs during press molding, enables a matrix resin to exhibit excellent fluidity and excellent quick curing properties during press molding, and makes it possible to obtain a fiber-reinforced composite excellent in mold release properties, mechanical characteristics, and heat resistance. The sheet molding compound of the present invention contains an epoxy resin composition and reinforcing fiber, in which a gel time of the epoxy resin composition is 30 to 140 seconds at 140° C., a temperature at the start of curing reaction of the epoxy resin composition is 70° C. to 115° C., and when b1 represents a viscosity of the epoxy resin composition measured at 30° C. 7 days after the preparation of the composition, and b2 represents a viscosity of the epoxy resin composition measured at 30° C. 14 days after the preparation of the composition, b1 and b2 satisfy b2/b1≤5.

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.

An intermediate base material is provided that is excellent in the conformity to three-dimensional shapes and that, when formed into a fiber reinforced plastic, develops good surface quality and high mechanical properties.

According to one aspect, an incised prepreg is provided that has, in at least a partial region in a prepreg that contains unidirectionally oriented reinforcing fibers and a resin, a plurality of incisions that divide reinforcing fibers, wherein, in the case where a population is made up of the numbers of incisions contained in ten small circular regions of 10 mm in diameter randomly selected in the aforementioned region, a mean value for the population is 10 or greater and a coefficient of variation therefor is within 20%.

An intermediate base material is provided that is excellent in the conformity to three-dimensional shapes and that, when formed into a fiber reinforced plastic, develops good surface quality and high mechanical properties.

According to one aspect, an incised prepreg is provided that has, in at least a partial region in a prepreg that contains unidirectionally oriented reinforcing fibers and a resin, a plurality of incisions that divide reinforcing fibers, wherein, in the case where a population is made up of the numbers of incisions contained in ten small circular regions of 10 mm in diameter randomly selected in the aforementioned region, a mean value for the population is 10 or greater and a coefficient of variation therefor is within 20%.