An ink formulation for additive manufacturing of low density syntactic foams is described. The ink formulation can include a thermoset resin, a curing agent suitable for use with the thermoset resin, a plurality of hollow spheres, such as glass microballoons, one or more solvents, and one or more non-hollow, viscosity modifying filler. Also described are a method of preparing the ink formulation, a method of preparing three-dimensional objects comprising low density syntactic foams, and the three-dimensional objects prepared thereby.

A method produces a partial split-fiber fiber bundle capable of stably separating a fiber bundle continuously for a long time even when a splice part is present in the partial split-fiber fiber bundle. The method produces a partial split-fiber fiber bundle in which when the fiber bundle having the splice part formed by joining fiber bundles is allowed to travel along a longitudinal direction, a part of the fiber bundle is separated by thrusting a protruding part of the fiber splitting means into the fiber bundle, and timing at which the fiber splitting means is thrust into the fiber bundle is changed based on position information of the splice part obtained by detecting the splice part.

Thermosetting plastics are recycled by process that begins with grinding the plastic into small pieces. This particulate is then mixed with a catalyst and ball mill milled to a fine powder, which can then be reprocessed via molding (e.g., hot-press, injection, etc.).

A random mat material including fiber bundles, said fiber bundles including fibers having an average fiber length of 5 to 100 mm, and having an average number N of fibers in the fiber bundle that satisfies: $\frac{1.5{10}^5}{D^2}<N<\frac{4.5{10}^5}{D^2}$
wherein D is the average diameter of fibers in the fiber bundle, expressed in micrometers, and the standard deviation SD.sub.N of the number of fibers in a fiber bundle satisfies:
1,000<SD.sub.N<6,000
wherein at an end of the fiber bundle, the number of the fibers in a fiber bundle becomes less from center to edge of the fiber bundle in a fiber direction.

A concentrate carrier system for adding colorants and/or other additives to resin formulations over a broad range of processing temperatures is described. The carrier system includes at least 20 wt. % of a base acrylate copolymer, such as ethyl-methyl acrylate, provided in combination with less than 30 wt. % of polycarpolactone, or a similar ring-opened cyclic ester or ether derivatives. The remainder, which may include an optional organic plasticizer such as epoxidized soybean oil, is dedicated to an additive package that may include colorants, property enhancers, and/or non-property fillers.

The present disclosure is directed to articles that include one or more coated fiber(s) (i.e., fiber(s) with a cured coating disposed thereon), where the coating includes a matrix of crosslinked polymers and optionally a colorant (e.g., pigment particles or dye or both). The cured coating is a product of crosslinking a coating composition including uncrosslinked polymers (e.g., a dispersion of uncrosslinked polymers in a carrier, wherein the uncrosslinked polymers are crosslinked to form the matrix of crosslinked polymers). The present disclosure is also directed to articles including the coated fibers, methods of forming the coated fibers and articles, and methods of making articles including the coated fibers.

A concentrate carrier system for adding colorants and/or other additives to resin formulations over a broad range of processing temperatures is described. The carrier system includes at least 20 wt. % of a base acrylate copolymer, such as ethyl-methyl acrylate, provided in combination with less than 55 or less than 30 wt. % of a ring-opened cyclic ester or ether derivative, such as polycaprolactone, polyhydroxyalkonates, polyglycolide, polylactide, poly(butylene succinate), other aliphatic linear polyesters. The remainder, which may include an optional organic plasticizer such as epoxidized soybean oil, is dedicated to an additive package that may include colorants, property enhancers, and/or non-property fillers.

A friction stir welding method using a resin composition including: a monomer (A) having an ethylenically unsaturated bond; a thermosetting resin (B); a radical polymerization initiator (C); and a fiber reinforcing material (D), wherein the thermosetting resin (B) is an unsaturated polyester resin or a vinyl ester resin.

An impregnated fibrous material including at least one fibrous material of continuous fibers and: at least one non-reactive thermoplastic polymer matrix, or at least one reactive thermoplastic prepolymer, which is a precursor of the non-reactive thermoplastic polymer, optionally mixed with a chain extender, wherein the at least one non-reactive thermoplastic polymer or the reactive prepolymer is an amorphous polymer or prepolymer having a glass transition temperature such that Tg80 C., or is a semi-crystalline polymer or prepolymer having a melting temperature Tf150 C., the fiber content in the pre-impregnated fibrous material being between 45 and 65 volume %, and the average thickness of the impregnated fibrous material being less than or equal to 100 m, independently of the number of fibers present in the fibrous material before impregnation.

The present disclosure generally relates to systems and methods for composites, including carbon fiber-metal composites. In some cases, the composites may be formed from one, two, or more layers of metals or other substrates, sandwiching a plurality of aligned fibers. The fibers may be substantially aligned, and may be present at relatively high densities within the composite. The composites may be prepared, in some aspects, by dispersing fibers by neutralizing the electrostatic interactions between the fibers, for example using aqueous liquids containing the fibers that are able to neutralize the electrostatic interactions that typically occur between the fibers. In some cases, the fibers may be aligned using techniques such as shear flow and/or magnetism. Other aspects are generally directed to methods of using such composites, kits including such composites, or the like.