The present invention relates to a phosphazene compound containing an ester group having a structure of formula (I). The present invention grafts ester groups to phosphazene compounds and makes terminal grafted hydroxyl and carboxyl groups reacted with polymer matrix, producing an improvement of flame retardancy and a reduction of dielectric constant at the same time when the phosphazene compound is introduced into polymer matrix. Since N and P atoms are directly bonded into the polymer matrix by a reaction rather than addition and combination means in the prior art, there is no reduced mechanical properties of the matrix due to the addition of flame retardants.

The present disclosure provides an impregnation device for a fiber prepreg, which includes a film layer separation assembly, a hot pressing element, and a thermal barrier element. The hot pressing element is disposed beneath the film layer separation assembly. The thermal barrier element is disposed between the film layer separation assembly and the hot pressing element. The present disclosure also provides an impregnation method for a fiber prepreg.

An epoxy resin, comprising an epoxy compound having a mesogenic structure, and having a value of η′2/η′1 equal to 3 or less, wherein η′1 is an initial dynamic shear viscosity (Pa.Math.s) and η′2 is a maximum value of dynamic shear viscosity (Pa.Math.s), in a measurement of dynamic shear viscosity.

A resin composition is provided. The resin composition comprises the following components: (A) a halogen-free epoxy resin; (B) a hardener; and (C) a phosphorus-containing phenolic resin of the following formula (I): ##STR00001##
wherein m, n, l, R.sub.1, and R.sub.2 are as defined in the specification.

The invention relates to a blank for compression moulding a part in a compression mould comprising one or more moulding recesses, said blank comprising a body formed from a first moulding compound comprising a fibrous reinforcement material and a thermo-curable resin material, and a region located on the surface of the body formed from a second moulding compound; said second moulding compound comprising a fibrous reinforcement material and a thermo-curable resin material, and exhibiting increased flow at one or more temperatures between 20° C. and the cured Tg of the first moulding compound compared to the flow of the first moulding compound at the same temperature.

The invention relates to a multilayer prepreg comprising a first and a second fiber prepreg, one or two micaceous prepregs and B staged thermosetting resin, which may be different for each layer or identical. The micaceous prepregs are positioned on the top (outside) of the fiber prepregs. There may be plurality of further fiber prepregs. The micaceous prepregs preferably comprise mica flakes in the form of a mica paper. The use of such prepreg as surfacing layer at the top of a composite material or near the top of a composite material can determine an improvement in burn-through and fire retardancy performance of composite materials. It is also disclosed a cured composite panel, such as an aircraft part, obtainable by curing the multilayer prepreg to a C stage.

Dry prepregs for ceramic matrix composites are described. The dry prepregs comprise a tow or fabric of ceramic fibers infiltrated with preceramic matrix comprising low levels of an aqueous solvent. The preceramic matrix contains an inorganic portion and a binder system. Binder systems comprising a binder and a plasticizer for the binder are described.

Provided is an insulating varnish composition, including: two or more kinds of epoxy resins; and a filler having an average primary particle diameter of 500 nm or less, wherein the two or more kinds of epoxy resins contain 80 mass % or more of an epoxy resin having a number of repetitions of 0 in a molecular structural formula thereof with respect to a total mass of the two or more kinds of epoxy resins.

A method of reducing the formaldehyde emission of a mineral fiber product bonded with a urea-modified phenol-formaldehyde resol resin-type binder comprises adding dextrose to the binder composition during and/or after preparation of the binder composition but before curing of the binder composition applied to the mineral fibers.

A resin-impregnated boron nitride body includes a polymer-derived boron nitride and a resin. A process for manufacturing such a resin-impregnated boron nitride body includes: polymerizing a boron nitride molecular precursor into a preceramic polymer shaping the preceramic polymer to form an infusible polymer body; submitting the polymer body to a thermal treatment to obtain a boron nitride body; impregnating the boron nitride body with a resin; and curing the resin.