700 results about "Cyclopentadiene" patented technology

To provide an epoxy resin composition that has low volume resistivity and exhibits suitable conductivity when formed as a coating film, and that makes it possible to form a coating film having excellent solder wettability and solder erosion resistance.SOLUTION: An epoxy resin composition contains the following components (A) to (D): (A) one or more epoxy resins selected from the group consisting of triphenylmethane-type epoxy resins, naphthalene-type epoxy resins, and phenol novolac-type epoxy resins; (B) one or more epoxy resins selected from the group consisting of polyether-modified epoxy resins, urethane-modified epoxy resins, mesogen-modified epoxy resins having an -O-CH2CH(OH)CH2-O- skeleton in the molecule thereof, bisphenol-type epoxy resins, and dicyclopentadiene-type epoxy resins; (C) an imidazole-based compound and / or a phenol-based compound; and (D) one or more conductive powders selected from among silver-coated copper powders, silver-based powders, nickel-based powders, conductive carbon powders, copper-based powders, and gold-based powders.SELECTED DRAWING: None

The present application relates to the technical field of colored tire rubber, and specifically discloses an anti-discoloration rubber composition for colored tires and its preparation method. An anti-discoloration rubber composition for colored tires is prepared by first preparing modified colored silica, then using solution-polymerized styrene-butadiene rubber, natural rubber, and EPDM as the rubber matrix, adding modified colored silica for coloring and reinforcement, and then adding polydicyclopentadiene resin, titanium dioxide, YDH-151 silane coupling agent, zinc oxide, stearic acid, sulfur and TBBS accelerator, protective wax, AFS / LG antioxidant, antistatic agent and other auxiliary agents to prepare the anti-discoloration rubber composition for colored tires. The anti-discoloration rubber composition for colored tires prepared in this application has the advantages of stable color, aging resistance, good tensile strength, strong wear resistance, and strong weather resistance.

The invention relates to a high-thermal-conductivity low-dielectric epoxy resin composition and a preparation method thereof, and the high-thermal-conductivity low-dielectric epoxy resin composition comprises the following raw materials in parts by weight: 13-16 parts of a thermal conductive filler, 45-50 parts of epoxy resin, 23-27 parts of a curing agent and 0.3-0.7 part of an accelerant, the heat-conducting filler comprises attapulgite, modified boron nitride and aramid fiber in a mass ratio of (0.7-0.9): (6-9): (0.2-0.5). The attapulgite, the modified boron nitride and the aramid fiber are used as heat-conducting fillers, the dicyclopentadiene epoxy resin and the bisphenol A epoxy resin are used as epoxy resin, and the epoxy resin with high heat conductivity and low dielectric property is prepared by means of weakening charge transfer among molecules, reducing polarization effect, forming a three-dimensional heat-conducting network and the like.

The invention relates to the technical field of polymer composite materials, in particular to an explosion-proof and impact-resistant polymer coating material for an aircraft shell. The coating is prepared from aliphatic polyurethane acrylate, cycloaliphatic epoxy resin, nano silicon dioxide, polyethylene glycol, polyurea microcapsules, dicyclopentadiene resin, a Grubb catalyst, graphene oxide, polysulfide rubber and the balance of auxiliary materials. According to the invention, aliphatic polyurethane acrylate is used as a flexible matrix, so that the risk of hydrolysis of aromatic isocyanate is avoided. The dicyclopentadiene resin is subjected to in-situ ring opening polymerization in the presence of a Grubbs catalyst and cooperates with the hydrophobic nano silicon dioxide to block water. The polyurea microcapsules are broken by impact to release silicone oil, and cracks are filled immediately to reduce friction. And a water molecule permeation path is prolonged by the mica powder sheet layer. And the epoxy-polyurethane network realizes micro-crack self-repairing through dynamic ester bond exchange, so that the anti-explosion and anti-impact functions of the coating and the structural stability of an aircraft shell in an extreme environment are guaranteed.

The present invention relates to a matting agent for HAA powder coatings and a preparation method thereof. The matting agent is a matting polymer containing special groups such as hydroxyl and epoxy groups with significantly different activities. The matting polymer is mainly prepared from glycidyl methacrylate, methyl methacrylate, butyl acrylate, 5-norbornene-2-methanol, 2-methyl-3-butene-2-ol, dicyclopentadiene dioxide, a hydroxyl polyester resin, and an accelerator. Due to the presence of hydroxyl and epoxy groups of varying activities in its structure, supplemented by the accelerator and the physical dispersion effect during the preparation process, the product has excellent matting ability and good storage and matting stability. It can reduce the gloss of HAA system powder coatings to 3-10%.

The invention provides a preparation method and application of an asymmetric dicyclopentadienyl dialkoxy zirconium compound, and the preparation method comprises the following steps: (1) mixing a solvent with ZrCl4 and sodium cyclopentadienyl CpNa, and carrying out a reaction to obtain CpZrCl3; (2) the CpZrCl3 obtained in the step (1) and R1 substituted sodium cyclopentadienyl R1CpNa are subjected to a mixed reaction, and (R1Cp) CpZrCl2 is obtained; and (3) mixing the (R1Cp) CpZrCl2 obtained in the step (2) with alkoxy sodium salt R2Na, and carrying out a reaction so as to obtain the asymmetric dicyclopentadiene dialkoxy zirconium compound. According to the method, the substitution reaction of three sodium salts is used for replacing the ligand replacement reaction in the prior art, so that the reaction steps are shortened, the use of unnecessary raw materials is avoided, the production cost is reduced, and the obtained target product is high in yield and high in purity.

The invention discloses a carbon fiber modified sizing agent as well as a preparation method and application thereof. The preparation method of the carbon fiber modified sizing agent comprises the following steps: (1) reacting 5-norbornene-2-methylamine with monofunctional epoxy resin to obtain slurry; and (2) dissolving the slurry prepared in the step (1) in an organic solvent to prepare the modified sizing agent. And then obtaining the modified carbon fiber through a dipping and sizing process. The method is simple in process, and the interface bonding strength of the carbon fibers and the polydicyclopentadiene can be greatly improved.

The invention provides a graphene dispersion liquid, a preparation method thereof and a water-based paint, aiming at solving the problem that the performance of graphene is influenced due to insufficient dispersion force and poor dispersion stability when a conventional dispersing agent is used for dispersing graphene in water in the prior art. The graphene dispersion liquid comprises a first solvent and modified graphene oxide, and the modified graphene oxide is dispersed in the first solvent; the modified graphene oxide comprises an inner core and a shell layer, the inner core is graphene oxide, the shell layer is a diene modified polymer, and the diene modified polymer is grafted on the inner core; the diene modified polymer comprises one or more of a cyclopentadiene modified polymer and a furan modified polymer. According to the graphene dispersion liquid provided by the invention, the diene modified polymer is grafted on the graphene oxide, and the graphene oxide is uniformly dispersed in the solvent by utilizing the hydrophilicity of the diene modified polymer, so that the graphene dispersion liquid with stable dispersion performance can be obtained.

The invention provides dicyclopentadiene phenol resin and a preparation method thereof, dicyclopentadiene phenol epoxy resin and a preparation method and application thereof. Compared with common dicyclopentadiene phenol resin, the dicyclopentadiene phenol resin has unsaturated cycloolefin active functional groups at the tail ends of molecular chains, so that the reactivity of the resin can be improved, and the application field of the dicyclopentadiene phenol resin is expanded.

The invention provides a synthesis method of tris (dimethylamino) cyclopentadienyl hafnium, which comprises the following steps: reacting hafnium tetrachloride with sodium dimethylamino at a first temperature under the protection of inert gas to form an intermediate; heating and settling, cooling to a second temperature, dropwise adding cyclopentadiene, and filtering, distilling and purifying to obtain a target product. According to the method, high yield and high purity are achieved by optimizing the raw material ratio and controlling the dropwise adding temperature and the use amount of cyclopentadiene. The byproduct sodium chloride is large in particle and easy to filter, the post-treatment process is remarkably simplified, and the process safety, controllability and industrial adaptability are improved.

The invention provides a preparation method of dicarbonyl cyclopentadienyl cobalt, which comprises the following steps: adding cobalt salt, a reducing agent, methyl formate and a catalyst into a high-pressure reaction kettle, keeping the reaction kettle in an inert gas atmosphere, and heating and stirring; cooling the high-pressure reaction kettle to room temperature, discharging gas, filtering reaction liquid, and putting filtrate into a normal-pressure reaction device in an inert gas atmosphere; and adding a cyclopentadiene monomer into the normal-pressure reaction device, carrying out heating reaction, filtering after the reaction is finished, and carrying out post-treatment on the obtained filtrate to obtain a dicarbonyl cyclopentadienyl cobalt crude product. The operation risk is reduced, the operation is simple, and the synthesis efficiency is high; cheap and easily available cobalt salt is used as a raw material, and a relatively cheap catalyst is used, so that the synthesis cost is low, and the method is suitable for industrial large-scale popularization and application.

The invention belongs to the technical field of semiconductor materials, and particularly relates to a hafnium precursor material and a preparation method and application thereof. The hafnium precursor material has a structure as shown in a formula (1). The hafnium precursor material with a specific structure is designed and synthesized, and the molecular structure of the hafnium precursor material contains an alkylene dicyclopentadienyl organic group structure, so that compared with an existing cyclopentadienyl hafnium precursor material (such as cyclopentadienyl) tris (dimethylamino) hafnium), the hafnium precursor material has higher thermal stability, and meanwhile, the hafnium precursor material can be used for preparing a hafnium precursor material. The viscosity is low, the film yield is improved, and the performance of the film prepared from the raw material is better. # imgabs0 #

The invention discloses a dicarbonyl cyclopentadienyl cobalt complex as well as a preparation method and application thereof, and belongs to the technical field of organic metal synthesis. The preparation method of the dicarbonyl cyclopentadienyl cobalt complex specifically comprises the following steps: (1) dissolving cobalt octacarbonyl in carbon monoxide pre-saturated dichloromethane, and continuously introducing carbon monoxide gas for protection to obtain a reaction system; (2) dissolving cyclopentadiene in dichloromethane, and continuously introducing carbon monoxide gas for protection to obtain a cyclopentadiene solution; (3) adding a cyclopentadiene solution into the reaction system, heating and stirring for reaction; and (4) carrying out pressurized distillation and rectification on the reaction system. According to the invention, the carbon monoxide protective gas is introduced and the cyclopentadiene solution is prepared in the whole process to reduce the decomposition of the raw materials and reduce the generation of byproducts, so that the subsequent purification difficulty is reduced, and the reaction yield and the economic benefit of the product are improved.

The invention discloses a packaging material as well as a preparation method and application thereof. The packaging material comprises the following components in parts by mass: 40-85 parts of matrix resin, 5-30 parts of phase change PCM particles, 3-20 parts of self-repairing microcapsules, 1-8 parts of an interface compatilizer and 10-20 parts of a heat-conducting network reinforcing material, the melting point of the phase change PCM particles is not more than 80 DEG C; a core layer of the self-repairing microcapsule comprises dicyclopentadiene and a ruthenium catalyst, and a shell layer of the self-repairing microcapsule comprises polyurea or polyurethane; the PCBA packaging material with the intelligent response function is formed by combining the low-melting-point phase-change PCM particles with the self-repairing microcapsule system, when the PCBA temperature is too high, the low-melting-point phase-change PCM particles are molten, junction temperature suddenly rising is restrained through melting heat absorption, meanwhile, the adjacent microcapsules are triggered to be broken through volume expansion, DCPD monomers are released and subjected to in-situ polymerization under the action of a catalyst, and the PCBA packaging material with the intelligent response function is obtained. Microcracks generated by thermal stress are rapidly repaired, and the heat dissipation stability and the electrical insulation reliability of the material in long-term thermal circulation are remarkably improved.

Yttrium complexes and related methods are provided. A method of making an yttrium complex comprising contacting a metal alkyl cyclopentadienyl compound with an yttrium trihalide compound in a non-coordinating solvent to obtain a tris (alkyl cyclopentadienyl) yttrium complex. A composition includes a tris (alkylcyclopentadienyl) yttrium complex.

A light emitting element of an embodiment includes a first electrode, a second electrode facing the first electrode, and functional layers disposed between the first electrode and the second electrode. At least one functional layer among the functional layers includes a monoamine compound of an embodiment thereby showing high efficiency and long life characteristics. The monoamine compound includes a substituted or unsubstituted phenanthryl group directly bonded to a nitrogen atom, a substituted or unsubstituted dibenzoheterole group directly bonded to the nitrogen atom, and a substituted or unsubstituted naphthyl group bonded to the nitrogen atom via a linker.

The invention discloses a preparation method of a mono-substituted cyclopentadienyl yttrium precursor, and relates to the field of chemical product preparation, the preparation method of the mono-substituted cyclopentadienyl yttrium precursor comprises the following steps: S1, adding mono-substituted cyclopentadiene into a solution of an alkali metal compound, and then carrying out a heating reaction; s2, dropwise adding the mixture obtained in the step S1 into a solution containing yttrium halide, and carrying out a reflux reaction; and S3, filtering the mixture in S2, and carrying out reduced pressure distillation to remove the solvent. According to the preparation method disclosed by the invention, by changing the solvent and controlling the equivalent weight of reactants and the reaction temperature, the yield can be improved, the purification step can be simplified, and the high-efficiency and large-scale preparation of the mono-substituted cyclopentadienyl yttrium can be realized.

The invention discloses an unsymmetrical dimethylhydrazine sensor of a Pt cluster loaded WO3 nanosheet sensitive material prepared based on atomic layer deposition and a preparation method of the unsymmetrical dimethylhydrazine sensor, and belongs to the technical field of semiconductor metal oxide gas sensors. The preparation method comprises the following steps: performing hydro-thermal synthesis on a WO3 nanosheet sensitive material by using sodium tungstate dihydrate, concentrated hydrochloric acid and citric acid monohydrate, and then preparing the Pt cluster-loaded WO3 nanosheet sensitive material by using trimethyl (methyl cyclopentadienyl) platinum (IV) as a Pt precursor and tert-butylhydrazine as a reducing agent and using an atomic layer deposition method. The material has high response (96.6-50ppm) and fast response recovery time (2 / 118s) to low-concentration UDMH gas under the working condition of 200 DEG C. The commercially available indirectly-heated structure sensor is simple in manufacturing process, small in size and beneficial to industrial batch production, has important application value and has wide application prospects in the aspect of UDMH detection in a specific environment.

The present invention provides a method for manufacturing an adhesive member, comprising the steps of applying an ultraviolet-curable silicone composition containing (A) an organopolysiloxane containing an unsaturated group, (B) an organohydrogenpolysiloxane, and (C) an ultraviolet-activated hydrosilylated platinum catalyst having a cyclopentadienyl group to which a condensed aromatic hydrocarbon group is bonded as a ligand, to a first substrate layer, and including in any order: (i) bonding the first substrate layer to which the ultraviolet-curable silicone composition has been applied to a second substrate layer via a layer of ultraviolet-curable silicone composition; (ii) depressurizing the ultraviolet-curable silicone composition applied to the first substrate layer under a pressure below atmospheric pressure; and (iii) irradiating the ultraviolet-curable silicone composition applied to the first substrate layer with ultraviolet light. The invention also provides an adhesive made of a silicone composition with excellent curability, and an adhesive member with high adhesiveness and high reliability as a component.

A method of rapidly forming an elastomer with tunable properties is described herein. The method includes preparing a monomer solution comprising a catalyst and one or more monomers including 1,5-cyclooctadiene (COD). The one or more monomers may further include dicyclopentadiene (DCPD), and each of the COD and the DCPD may be present in the monomer solution at a predetermined volume percentage. A region of the monomer solution is activated to initiate an exothermic polymerization reaction and generate a self-propagating polymerization front, which moves through the monomer solution and polymerizes the one or more monomers. Thus, an elastomer having predetermined properties is rapidly formed.

The invention discloses an epoxy resin material for electronic plastic package of a radio frequency chip and a preparation method of the epoxy resin material. The preparation method comprises the following steps: firstly, carrying out alkylation reaction on dicyclopentadiene and phenol in the presence of a catalyst boron trifluoride diethyl etherate to synthesize dicyclopentadiene phenol resin, and epoxidizing the dicyclopentadiene phenol resin through epoxy chloropropane to obtain dicyclopentadiene epoxy resin DCPDDE; then, synthesizing a poly (dicyclopentadiene) linear polymer PDCPD by taking a Pd / Ag ionic compound as a catalyst, and then reacting the PDCPD with cysteamine sulfydryl to obtain dicyclopentadiene cysteamine PDCPDAm; and finally, mixing the DCPDDE, the PDCPDAm, the filler and the coupling agent, stirring, defoaming and curing to form the thermosetting resin with a three-dimensional network structure. The synthetic process is simple, the cost is low, the mobility and polarizability of molecules are limited due to high rigidity and low polarity of the obtained resin, transmission of a radio frequency chip under a high-frequency high-speed signal is ensured, stable operation in a complex working environment is ensured, reliable packaging protection is provided for the radio frequency chip, and the service life of the radio frequency chip is prolonged. And the thermal stability and the low dielectric property of the radio frequency chip are improved to the greatest extent.

The invention relates to the technical field of electronic materials, in particular to a copper-clad plate resin composition with an ultralow-loss medium and a preparation method of the copper-clad plate resin composition. The composition comprises the following components: modified polyphenyl ether, dicyclopentadiene epoxy resin, trifunctional epoxy resin, active ester, cyanate ester, DMAP, spherical silicon dioxide and a POSS-silicon dioxide compound, the preparation method comprises the following steps: carrying out surface norbornenylation modification on bimodal spherical silicon dioxide, and carrying out click reaction on the bimodal spherical silicon dioxide and octa-aminophenyl polysilsesquioxane with tetrazinyl at the tail end to prepare a POSS-silicon dioxide compound, so as to construct an interface transition layer with gradient modulus. According to the invention, collaborative optimization of dielectric loss, thermal mechanical properties and interface bonding strength is realized, and the material has excellent properties of low dielectric loss, high thermal stability, high peel strength and the like, and is suitable for the fields of 5G communication, high-frequency electronic equipment and the like.

According to the organic silicon modified epoxy self-repairing anti-corrosion coating and the preparation method and application thereof, amino functionalized graphene, nano silicon dioxide and self-repairing microcapsules (dicyclopentadiene) are added into a coating formula in a chemical modification mode, the molecular structure of epoxy resin (bisphenol A type) is optimized, and the self-repairing anti-corrosion coating is prepared. On the basis of enhancing the physical and mechanical properties of the coating, better physical and mechanical properties, corrosion resistance, heat resistance and self-repairing functions of the coating are further realized. The coating can meet protection of parts with high corrosion resistance, high application environment temperature and abrasion and damage problems, is specifically applied to the fields of high-temperature pipeline protection, corrosion resistance of lithium battery shells, engine blades, photovoltaic supports and the like, and can prolong the service life of related parts and equipment.

According to the modified water-based alkyd resin based on dicyclopentadiene and the preparation method of the modified water-based alkyd resin, the water-based alkyd resin is modified by combining diacrylic acid, cyclopentadiene modification and tung oil, and the rigidity of cyclopentadiene modification and the flexibility of tung oil achieve the modification effect of combining rigidity and softness; the problems of poor storage stability, low paint film hardness and insufficient water resistance of traditional water-based alkyd resin are successfully solved, the storage period of the water-based alkyd resin water-based paint is greatly prolonged, the formed paint film is high in drying speed and high in hardness and has good adhesive force, impact resistance, weather resistance and corrosion resistance, the production process is stable and controllable, and the production cost is low. Wide application prospects and economic values are realized.

The invention discloses a preparation method of a monocyclopentadienyl trialkoxy titanium precursor, and belongs to the technical field of synthesis of metal organic compounds. The method comprises the following steps: S1, reacting a deprotonation product of RnCp, (R0) mSiXz and an accelerant to obtain an intermediate I; s2, reacting the intermediate I with TiX4 to obtain an intermediate II; s3, the intermediate II and R1OM are subjected to a reaction, and a monocyclopentadienyl trialkoxy titanium precursor is prepared; r and R1 are independently selected from C1-C5 straight-chain or branched-chain alkyl groups, Cp is cyclopentadienyl, R0 is C1-C3 alkyl groups, X is halogen and is selected from any one of F, Cl, Br and I, n is an integer of 0-5, m + z is equal to 4 and 1 < = z < = 2, and M is alkali metal. The synthesis route has good safety and economical efficiency, the yield of the industrial synthesis route is remarkably improved, the reaction time is short, the synthesis efficiency is high, and the industrial application value is high.

The invention discloses a high-temperature-resistant resin glue solution for a copper-clad plate and a preparation method of the high-temperature-resistant resin glue solution, and relates to the technical field of copper-clad plates. The high-temperature-resistant resin glue solution is prepared from the following raw materials in parts by mass: 60 to 80 parts of dicyclopentadiene phenol type epoxy resin, 20 to 40 parts of fluorinated benzoxazine, 10 to 30 parts of dicyclopentadiene phenol type phenolic resin, 5 to 10 parts of hyperbranched polysiloxane, 90 to 100 parts of solvent, 5 to 8 parts of additive and 10 to 20 parts of inorganic filler. Wherein trifluoromethyl and naphthalene rings are introduced into the fluorinated benzoxazine, so that the heat-resistant stability and the dielectric property of the resin glue solution are effectively improved; a copper-clad plate sample prepared from the resin glue solution has a good application effect.

The application belongs to the technical field of organic compound synthesis and the field of polymer preparation, and discloses a method for directly preparing a cycloolefin copolymer from dicyclopentadiene and ethylene based on a continuous flow reactor; the continuous flow reactor is used to efficiently prepare norbornene and derivatives thereof from ethylene and dicyclopentadiene, and then the norbornene and derivatives thereof are used to prepare a cycloolefin copolymer from excessive ethylene. The application uses dicyclopentadiene and ethylene as raw materials, realizes a continuous process from the synthesis of a cycloolefin monomer to the preparation of a cycloolefin copolymer, and the cycloolefin monomer does not need to be separated and stored and can directly participate in the polymerization reaction, so that the original complicated process is effectively simplified, energy consumption is reduced, the catalyst in the polymerization stage is not easy to be deactivated even at high temperature, the catalytic efficiency is high, and a high polymer yield can be obtained in a very short time.

The invention discloses a tetracyclododecene preparation method, which comprises: mixing an N-methyl pyrrolidone (NMP) solvent, norbornene and toluene, heating to a reaction temperature in a reaction kettle, dropwise adding cyclopentadiene, and carrying out a Diels-Alder reaction in the reaction kettle to prepare tetracyclododecene, the high-purity tetracyclododecene with the mass content of 99% or above can be obtained through subsequent rectification. According to the process, cyclopentadiene is dropwise added, so that the reaction time is shortened, side reactions are reduced, the reaction is carried out in a liquid phase by taking NMP (N-Methyl Pyrrolidone) with a higher boiling point as a solvent, the reaction temperature can be reduced, the reaction process can be carried out at normal pressure, the production safety is improved, and the production operation cost is reduced.

The invention discloses a manufacturing method of a composite prepreg with interface and matrix self-repairing capability. Belongs to the technical field of composite material intermediate manufacturing. The preparation method comprises the following steps: mixing dicyclopentadiene and a catalyst thereof, and epoxy resin and a curing agent thereof to obtain a microcapsule active component; adding the mixture into a prepolymer solution used as a shell material, emulsifying, adjusting the pH value, heating and curing to finish the reaction, washing, filtering and drying to obtain microcapsules; mixing the epoxy resin with a catalyst in matrix resin to obtain prepreg resin; and controlling viscosity and curing degree to form a resin film or wet resin, and combining the resin film or wet resin with unidirectional fiber cloth and the like through a solvent or a hot melting method. By combining the characteristics of rapid prototyping and self-repairing of PDCPD and utilizing the interface repairing capability provided by the low-content epoxy resin in the formula, rapid and synchronous high-strength interface and matrix self-repairing which cannot be realized by the existing composite material is realized, and the defect that after a composite material structural part is damaged, the self-repairing performance of the composite material is greatly improved is overcome. And in-situ repair cannot be rapidly carried out.

The invention relates to the technical field of tire rubber manufacturing, and discloses a butyl inner tube rubber composition with an ultralow air permeability coefficient and a preparation method thereof. The superfine washed kaolin and the dicyclopentadiene hydrogenated resin are added into the rubber composition, do not affect the excellent elasticity of traditional butyl rubber and can synergistically improve the air tightness of the butyl inner tube rubber composition, so that the situation that the gas permeability of a butyl inner tube is increased under the conditions of high temperature, complex road conditions and long-term use is avoided, and the service life of the butyl inner tube is prolonged. And the risk of tire burst caused by low tire pressure due to the increase of the gas permeability of the butyl inner tire is reduced. The invention provides a solution for improving the long-acting sealing performance of the butyl inner tube of the heavy-duty vehicle, and has obvious economic benefit and environmental protection value.