Low-density, thermoplastic foams comprising: (a) thermoplastic polymer cells comprising cell walls comprising polyethylene furanoate, wherein at least about 50% by volume of the cells are closed cells; and (b) at least HFO-1234ze(E) contained in said closed cells.

Disclosed, among other things, are ways to manufacture reduced density thermoplastics using rapid solid-state foaming and machines useful for the saturation of plastic. In one embodiment, a foaming process may involve saturating a semi-crystalline polymer such as Polylactic Acid (PLA) with high levels of gas, and then heating, which may produce a reduced density plastic having high levels of crystallinity. In another embodiment, a foaming process may produce layered structures in reduced density plastics with or without integral skins. In another embodiment, a foaming process may produce deep draw structures in reduced density plastics with or without integral skins. In yet another embodiment, a foaming process may utilize additives, blends, or fillers, for example. In yet another embodiment, a foaming process may involve saturating a semi-crystalline polymer such as Polylactic Acid (PLA) with high levels of gas, and then heating, which may produce a reduced density plastic having high levels of crystallinity.

The invention provides a powder pre-preg comprising as sole resin a vinyl ester resin having a Tg in the range of −5 to +30° C. and a melt viscosity @100° C. in the range of 2 to 75 dPa.Math.s, which can be used in making a composite at a temperature as low as 80° C.

Various methods of reshaping and recycling thermoset polymers and composites containing thermoset polymers are provided. The methods involve the bond exchange reaction of exchangeable covalent bonds in the polymer matrix with a suitable small molecule solvent in the presence of a catalyst. In some aspects, the methods are applied to a carbon fiber reinforced polymer or a thermoset polymer where the thermoset polymer matrix includes a plurality of ester bonds. Using a small molecule alcohol, the methods provide for recycling one or both of the carbon fiber and the polymer, for welding two surfaces, or for repairing a damaged surface in the materials.

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 novel promotor which contains an aniline derivative is introduced. By using the promotor alone, the time and temperature of the curing reaction of the vinyl ester resin can be controlled by the unique steric effect and electronic properties of the aniline derivative. A method for preparing the above promotor is also introduced.

A composite formulation for use in lightweight molded components includes an untreated low density filler, such as glass bubbles, a solvated polymer mixture, and polymer paste. In one embodiment the solvated polymer mixture is used to treat the low density filler to form a treated low density filler. The solvated polymer mixture many include a thermoplastic resin or a reactive resin and an additive package. The additive package may include a dispersing agent and a silane carrier composition.

Resin particles include resin base particles and silica particles on surfaces of the resin base particles. The silica particles contain a quaternary ammonium salt and have hydrophobized surfaces. A difference (detection temperature A−detection temperature B) between a detection temperature A and a detection temperature B is more than 50° C., where the detection temperature A is a detection temperature from a pyrolysis product of the quaternary ammonium salt determined by pyrolysis mass spectrometry of the resin particles before cleaning, and the detection temperature B is a detection temperature from the pyrolysis product of the quaternary ammonium salt determined by pyrolysis mass spectrometry of the resin particles after cleaning.

A process for preparing a composite part, the process comprising: recovering unsaturated resin prepreg scrap; combining the recovered unsaturated resin prepreg scrap with a second resinous thermosetting component; and co-molding the prepreg scrap and resinous thermosetting component together under a pressure of 25 to 4000 psi and at a temperature of 100-400° F.

Disclosed is a cover for a utility vault and a method for making such covers. The cover is formed from fiberglass reinforcement layers and a polymer mix matrix. The reinforcement layers include a bottom reinforcement layer, one or more edge reinforcement layers, and a top reinforcement layer. A first portion of the edge reinforcement layer overlaps a portion of the bottom reinforcement layer and a second portion of the edge reinforcement layer overlaps a portion of the top reinforcement layer. The reinforcement layers are formed from fiberglass fabric and may include fiberglass layers whose fibers are oriented quadraxially. The polymer mix impregnates the fabric layers and forms the bulk of the cover. The polymer matrix bonds the reinforcement layers so that forces applied across the top and bottom layers are communicated to the edge reinforcement layer. The polymer matrix includes a thermoset polymer resin and an expanded glass bead filler.