237results about How to "High carbon residue rate" patented technology

The invention relates to an epoxy resin composition as well as a prepreg and a laminated board made of the same. The epoxy resin composition comprises the following components in parts by weight: 1-50 parts of modified polyphenylene oxide resin, 30-80 parts of epoxy resin, 20-60 parts of active ester curing agent, 0-50 parts of filler and 1-20 parts of assistant. The prepreg made of the epoxy resin composition comprises a base material and the epoxy resin composition which is attached to the base material through soaking and drying. The laminated board made of the epoxy resin composition comprises a plurality of laminated prepregs, wherein each prepreg comprises a base material and the epoxy resin composition which is attached to the base material through soaking and drying. The invention has the advantages of high heat resistance, high fire retardancy, low dielectric constant, low dielectric loss, excellent high-frequency dielectric properties and the like, and is suitable to be used as a high frequency circuit substrate material.

The present invention discloses a phenol-formaldehyde cyanate resin. It provides its chemical formula and synthesis method, and ablative composite material formed from the the above-mentioned phenol-formaldehyde cyanate resin.

The invention discloses a preparation method of a natural flake graphite-based negative electrode material. The method specifically comprises the following steps of: (1) crushing and processing natural flake graphite, carrying out purifying and drying, then infiltrating the product with a phenolic resin solution, finally evaporating the used solvent, and carrying out pre-carbonization on the obtained graphite under nitrogen protection of 550-750 DEG C; (2) adding the pre-carbonized graphite obtained in the step (1) to pitch coke micro powder for mixing, carrying out shaping and crushing until the tap density is 0.95-1.00g/cm<3>, adding the crushed graphite to dimethicone for mixing, carrying out pre-carbonization under nitrogen protection of 550-750 DEG C and carrying out sieving and magnetic deironing; and (3) carrying out carbonization treatment on the pre-carbonized graphite obtained in the step (2) under nitrogen protection of 950-1250 DEG C to obtain the natural flake graphite-based negative electrode material. The negative electrode material is high in yield, good in material liquid absorption and holdup properties and good in electrochemical properties.

The invention relates to triazine-containing benzoxazine, a triazine-containing benzoxazine polymer, and a preparation method thereof. The preparation method is characterized by: adopting cyanophenol as a raw material; adopting trifluoromethanesulfonic acid or trifluoroacetic acid as a catalyst; synthesizing triazine-containing trihydric phenol (TP for short) in dichloromethane or chloroform or acetone at a common temperature; adopting the synthesized TP, formaldehyde and aminated compounds as reaction raw materials; adopting a alkali as the catalyst, and carrying out a reaction in a alcohol solvent or a ether solvent to synthesize a series of triazine-containing polycyclic benzoxazine monomers (BZ for short) which have not been reported; heating the BZ to carry out a ring-opening polymerization to form polybenzoxazine (PBZ for short). A structural formula of the monomer BZ is shown as follow, substituents R are shown in the specification. The synthesized novel monomer provided by the present invention contains a triazine ring structure, such that the triazine content in the PBZ resin can be substantially raised so as to notably improve heat resistance, residual carbon rate, fire resistance property and wave transmission property of the PBZ.

The invention relates to a fluorenyl Cardo type polymide diluting agent and a preparing method and application thereof. The structural formula of the diluting agent is shown in the specification. The preparing method comprises the steps that under mechanical stirring and inert gas shielding, BAFL and an end-capping reagent PEPA are dissolved in an organic solvent for a reaction at the room temperature for 2-16 hours, and a polymide acid solution is obtained; then, a dehydrating agent and a dehydrating catalyst are dripped for a reaction at 20-80 DEG C for 3-12 hours, cleaning, filtering, drying and grinding are carried out, and the diluting agent is obtained. The diluting agent is applied to preparation of modified phenylacetylene phthalic terminated polymide resin. By means of the blending modification of the active diluting agent, under the situation that the softening point of a prepolymer is not increased, the glass-transition temperature of the cured polymide resin is increased by 43 DEG C, and the carbon yield in the nitrogen atmosphere at 800 DEG C is increased by 5%; the diluting agent has potential application value in the fields of preparing high-performance advanced composites, high-temperature resistance adhesives and the like as an additive.

The invention discloses a method for preparing multi-walled carbon nanotubes from phthalocyanine iron polymer by high temperature solid-phase cracking, belongs to the technical field of nanomaterials, and provides a simple, high-efficiency and low-cost method for preparing the multi-walled carbon nanotubes. The method comprises the following steps of: performing reflux reaction on bisphthalonitrile and an iron-based catalyst in N-methylpyrrolidone solvent to generate a phthalocyanine iron oligomer; heating and curing the phthalocyanine iron oligomer to obtain the phthalocyanine iron polymer; and finally performing the high temperature solid-phase cracking on the phthalocyanine iron polymer under the protection of an inert gas to obtain the multi-walled carbon nanotubes. By using the two iron-based catalysts of carbonyl iron powder and iron nanopowder, the hollow carbon nanotubes and the carbon nanotubes of which the cores are filled with iron nanopowder can be obtained respectively. The multi-walled carbon nanotubes prepared by the method has high purity, uniform tube diameter and length and can be widely applied to the high-technology fields such as various composite materials, microelectronics and the like.

The invention relates to the field of high molecular materials, in particular to a halogen-free flame-retardant epoxy resin composition and application thereof. The composition comprises 100 parts ofepoxy resin, a halogen-free composite flame retardant provided with diphenylphosphine oxide flame-retardant groups, 5-15 parts of a main flame retardant, 0-10 parts of an auxiliary flame retardant, 2-30 parts of a curing agent and 0-1 part of a curing accelerating crosslinking agent. The composition further comprises a mixture of at least two of reinforced fibers, a flexibilizer, a filler, a silane coupling agent and a solvent. The composite flame retardant containing the diphenylphosphine oxide groups is high in flame-retarding efficiency and small in adding amount and has excellent compatibility and dispersity with the epoxy resin; and in the curing process, intermolecular dispersion with the epoxy resin can be realized, and the original transparent state of the epoxy resin is maintained. The finally cured flame-retardant resin composition has the advantages of low cost, high transparency, low water absorption rate, high glass conversion temperature, high thermal stability, low dielectric constant and dielectric loss, high flame retarding and the like.

The invention discloses a novel silicon-containing benzoxazine monomer and a preparation method thereof. The silicon-containing benzoxazine monomer is synthesized through reaction of silicon-containing diphenol, an amine compound and paraformaldehyde under a solvent reflux condition; and silicon-containing diphenol is prepared through reaction of phenol halide and chlorosilane. The preparation method of the silicon-containing benzoxazine monomer comprises the steps of adding silicon-containing diphenol, the amine compound and paraformaldehyde into a round-bottom flask containing benzene, methylbenzene or chloroform, carrying out heating reflux, and after the reaction is complete, separating, so as to obtain the silicon-containing benzoxazine monomer. The silicon-containing benzoxazine monomer is put into a round aluminum mold, the round aluminum mold is put into an electric-heating constant-temperature drying tank and is cured at different temperatures in different stages in the electric-heating constant-temperature drying tank, and then ring-opening polymerized polybenzoxazine is obtained. The silicon-containing benzoxazine has high heat stability and carbon residue rate, excellent flame retardance, dielectric property and corrosion resistance and can be applied to the fields of ablation-resistant materials, flame-retardant materials, anti-corrosion materials, electronic packaging and the like.

The invention belongs to the technical field of polymer synthesis and relates to a synthetic method of a hyperbranched polymer and application of the hyperbranched polymer in modified thermosetting resin. Particularly, the hyperbranched polymer is synthesized by adopting a 'one-pot method', and the synthetic method is simple, environment-friendly and efficient. The surface of the hyperbranched polymer contains a plurality of functional groups and can be modified according to actual needs; and by using the hyperbranched polymer as a modifying agent of the thermosetting resin, obvious viscosityreducing and toughening effects can be achieved. Compared with the existing synthetic method, the synthetic method provided by the invention has the advantages of wider application prospects, higher economic benefits, more environment protection and the like.

The invention provides a preparation method of amino POSS (polyhedral oligomeric silsesquioxane) graft modified ablation-resistant phenolic resin, which comprises the following steps: preparing phenoland aldehyde according to the molar ratio of 1:(1.0-1.5), adding a catalyst, and carrying out a reaction to generate a hydroxymethyl-containing phenolic resin polymer; preparing amino POSS, wherein the mass ratio of the amino POSS to the phenol in the step (1) is (1-10):100, and dissolving the amino POSS and the phenol in the step (1) in a solvent to form an amino POSS solution; and adding the amino POSS solution into the polymer containing hydroxymethyl phenolic resin, and carrying out a reaction until the amino POSS graft modified ablation-resistant phenolic resin is generated. The invention also provides the phenolic resin prepared by the preparation method of the amino POSS graft modified ablation-resistant phenolic resin. The preparation method is high in modification efficiency, andthe obtained modified phenolic resin is excellent in ablation resistance.

The invention discloses a single molecular expansion type alkyl phosphinate flame retardant. A structural general formula is shown in the description, a molecular structure is starlike, R-O- is a hydroxyl dehydrogenized structure after a nitrogen-containing polyhydroxy compound is subjected to esterification reaction, the formula (shown in the description) is a hydroxyl removed structure provided with molecular hydroxyl and obtained after organic phosphonic acid esterification reaction, n corresponds to the number of hydroxy and amidogen of the nitrogen-containing polyhydroxy compound, and M is a metal or semi-metal having the valence m. The invention further discloses a preparation method the flame retardant. The three-source proportion of the flame retardant can be regulated and controlled by selecting different nitrogen-containing polyhydroxy compounds. The molecular structure contains P-C keys and has excellent heat stability and good chemical properties. A specific carboxylic ester structure has good mixing compatibility with a polymer, and the original mechanical properties of the polymer can be retained to the greater degree. Metal ions in molecules can prevent the flame retardant from migrating from the polymer and meanwhile have a catalytic charing effect.

The invention relates to a zirconium-modified phenolic resin and a preparation method thereof. The zirconium-modified phenolic resin is technically characterized by being prepared from the following raw materials in parts by weight: 20-50 parts of phenol, 9-20 parts of formaldehyde, 2-10 parts of sodium hydroxide, 20-40 parts of ethanol, 10-20 parts of acetylacetone, 5-20 parts of zirconium oxychloride, and 0.5-2 parts of hydrogen peroxide. The preparation method comprises the following steps of: charging raw materials, refluxing, stirring, dropwise adding zirconium oxychloride ethanol solution, adjusting the pH value, discharging, and removing the solvent to obtain the zirconium-modified phenolic resin. The preparation method is simple, the cost is low, the content of zirconium is controllable, the prepared zirconium-modified phenolic resin has higher carbon yield, as well as good heat resistance, ablation resistance and mechanical property, is wide in application range, and has obvious economic and social benefits.

The invention discloses a method of preparing hard carbon felt. The method includes the following steps that S1, a mesh blank prepared from short-cut pre-oxidized fiber by carding and air-laying is adopted; S2, phenolic resin with a high carbon residue rate is adopted as a precursor; S3, anhydrous ethanol is adopted as a solvent; S4, a PAN pre-oxidized fiber mesh blank is subjected to lamination and relay needle punching on a needle punching machine to the required thickness according to the process design. According to the method of preparing the hard carbon felt, the pre-oxidized fiber is adopted as a raw material, overall pre-oxidized fiber felt is obtained after relay needle punching and severs as a preform, and overall hard thermal-insulating carbon fiber felt is prepared through carbonization, impregnation, curing, graphitization and other processes; because the density of a material has large impact on the mechanical and thermal properties of the material, the density of the overall hard carbon fiber felt prepared by the method is only 0.16 g/cm<3>, the thermal conductivity of the overall hard carbon fiber felt at 1500 DEG C is 0.25 w/(m.k.), and both of the density and thethermal conductivity of the overall hard carbon fiber felt are lower than that of traditional solidified felt formed by bonding soft carbon felt and an interlayer, it is indicated that the main properties of the overall hard carbon fiber felt are better than those of the traditional carbon felt.

The invention relates to applications of cyclic phosphorus-nitrogen synergic halogen-free flame retardant, and particularly relates to applications of 2,7-bis(N,N-dimethylamine)-1,6,3,8,2,7-octahydrodioxadiazole diphosphinic acid, belonging to the field of synthesizing a novel halogen-free high polymer material. As a hard segment chain extender, 2,7-bis(N,N-dimethylamine)-1,6,3,8,2,7-octahydrodioxadiazole diphosphinic acid is applied to halogen-free flame-retardant modification of water-based polyurethane emulsion. Cyclic phosphamide flame retardant 2,7-bis(N,N-dimethylamine)-1,6,3,8,2,7-octahydrodioxadiazole diphosphinic acid as the hard segment chain extender is embedded into a water-based polyurethane macromolecular chain; the research shows that due to the addition of the flame retardant, the limit oxygen index of a polyurethane membrane can be improved to a greater extent, the thermal stability of the polyurethane membrane is enhanced, the carbon residue rate of the material after which is decomposed at high temperature is increased, and the usage amount of the flame retardant is reduced.

The invention discloses a method for recovering and preparing a carbon/carbon preform from a carbon fiber reinforced resin matrix composite material, and the method comprises the following steps: (1)pre-pyrolyzing the carbon fiber reinforced resin matrix composite material under an inert atmosphere to produce holes on the carbon fiber reinforced resin matrix composite material to obtain a pre-pyrolyzed product; (2) fully immersing a carburant melt or a carburant-containing solution in the holes of the pre-pyrolyzed product, taking the pre-pyrolyzed product out and drying; (3) pyrolyzing the dried carburant-containing pre-pyrolyzed product under the inert atmosphere to sufficiently convert a resin matrix into deposited carbon to obtain the carbon/carbon preform. The method not only fully recovers the resin matrix by the carburant, but also converts the resin matrix into the deposited carbon, the recovered carbon fiber is regular, and the mechanical properties of the recovered carbon fiber are not degraded, and the prepared carbon/carbon perform d can be used for preparing high value-added carbon/ carbon composite materials and carbon/ceramic composite materials, and forward development of high-value reuse of the carbon fiber reinforced resin matrix composite material can be realized.