612 results about "Dimethyl terephthalate" patented technology

The present invention is a method of preparing a high molecular weight copolyester bottle resin that has excellent melt processing characteristics. The method includes the steps of reacting a diacid or diester component and a diol component to form modified polyethylene terephthalate, wherein diol component is present in excess of stoichiometric proportions. Together, the diacid or diester component and the diol component must include at least 7 percent comonomer. The remainder of the diacid component is terephthalic acid or dimethyl terephthalate and the remainder of the diol component is ethylene glycol. The modified polyethylene terephthalate is copolymerized in the melt phase to an intrinsic viscosity of between about 0.25 dl/g and 0.40 dl/g to thereby form a copolyester prepolymer. Thereafter the copolyester prepolymer is polymerized in the solid phase to form a high molecular weight bottle resin that has an intrinsic viscosity of at least about 0.70 dl/g, and a solid phase density of less than 1.413 g/cc.

A P-contained flame-retarding ethanediol polyterephthalate/laminar silicate composition is prepared from dimethyl terephthalate (or terephthalic acid), ethanediol, laminar silicate, P-contained flame retardant, intercalator, dispersing medium and catalyst. Its advantages are high mechanical properties and refractory nature, and simple preparing process.

The processes and articles of the present invention use thermally stable and loft retentive polymers in sublimation printed flock fibers, which are particularly attractive for forming molded and heat laminated articles. The process and articles use high, medium and low energy dyes on the fibers. A preferred polymer for use in the fibers is poly(cyclohexylene-dimethylene terephthalate).

The invention provides a PET-based graphene composite material, a preparation method thereof, and an aerostat. The preparation method comprises the following steps: 1, carrying out an esterification reaction or an ester interchange reaction on ethylene glycol modified graphene oxide and a PET monomer to obtain a head product, wherein the PET monomer is terephthalic acid and/or dimetyl terephthalate; and 2, carrying out a condensation polymerization reaction on the head product to obtain the PET-based graphene composite material. The in situ polymerization reaction of the ethylene glycol modified graphene oxide and the PET monomer is carried out to make graphene oxide be dispersed in the reaction process of ethylene glycol and the PET monomer, so the dispersibility of graphene in the PET-based graphene composite material is improved. The preparation method directly adopting the PET monomer as a raw material has the advantages of simple process, short preparation period, low cost, and suitableness for large-scale technologic production; and the PET-based graphene composite material prepared in the invention has excellent gas barrier property and mechanical strength.

Mixtures of terephthalate diesters having lowered freezing points and methods of making the terephthalic acid diesters. The method includes contacting a first alcohol, a second different alcohol and dimethyl terephthalate in the presence of a catalyst to thereby form the terephthalate diesters.

The invention discloses a phosphorus-containing PTT fire-resistant copolyesters/ nano composite material which is formed after carrying out in-situ polymerization on terephthalic acid or dimethyl terephthalate, 1,3-propanediol, a phosphorus-containing fire-resistant monomer and inorganic nano-particles, wherein the phosphorus-containing fire-resistant monomer accounts for 1-20 percent of the fire-resistant copolyesters in weight, the inorganic nano-particles account for 0.1-15 percent of the fire-resistant copolyesters in weight, and the intrinsic viscosity of the composite material is 0.5-2.0dL/g. The invention also discloses a preparation method thereof. Because the phosphorus-containing fire-resistant monomer is a reactive flame retardant and the nano-particles are added in an in-situ composite way, the composite material has enhanced fire resistance and mechanical property and obtains higher molecular weight by further solid phase polymerization. The invention has simple technical operation, low cost and easy application.

The invention relates to a method for preparing phosphorus halogen-free flame retardant copolyester. The method is characterized in that halogen-free phosphoric copolymerized flame retardant and glycol are mixed to carry out esterification reaction for 4 to 6 hours under the temperature of 140-210 DEG C and the pressure of 40-70Kpa and then are filtered; flame-retardant esterified product solution is prepared from the filtrate; dimethyl terephthalate, the glycol and promoter are mixed to carry out ester exchange reaction for 2 to 4 hours under the temperature of 160-240 DEG C; after the reaction, the flame-retardant esterified product solution is added, and catalyst and stabilizing agent are added to carry out polyreaction for 2.5 to 4 hours under the temperature of 240-290 DEG C and the pressure of 100Pa; and the phosphorus halogen-free flame retardant copolyester is prepared after discharging the material. Polyester slice can be used as raw material for producing film with flame retardance of grade 94UL V-O or grade VTM-O (collectively called grade VO), flame retardant fibre with flame retardance of grade I or above and grade VO flame retardant plastic product, and the polyester slice has excellent flame retardance.

The present invention relates to a corona-resisting insulated wire enamel for adjustable frequency motor and its preparation process. Said insulated wire enamel is formed from two portions of polyesterimine paint containing isocyanurate (THEIC) and nano material for quantum screening, and it is characterized by that its composition includes (by 100 portions) 10-20 portions of dimethyl terephthalate, 4-10 portions of glycerin, 5-20 portions of ethanediol, 5-12 portions of THEIC, 0.1-0.2 portion of catalyst, 5-15 portions of metabenzene diformic anhydride, 4-8 portions of 4,4-diaminodiphenyl ether, 0.2-0.3 portion of solidifying agent, 4-10 portions of screening agent, 0.5-2 portions of compounding agent, 15-40 portions of solvent, 10-35 portions of diluting agent and 0.5-1.5 portions of adjuvant.

The invention discloses a preparation method of cationic dyeable flame-retardant polyester resin. The manufacturing method is characterized by comprising the following steps: performing an esterification reaction on a halogen-free copolymerized phosphorus-based flame retardant, ethylene glycol and a composite catalyst to prepare an esterification solution of the halogen-free copolymerized flame retardant; performing ester exchange reaction on sulfoisophthalic acid dimethyl ester and the ethylene glycol to prepare a sulfonate-based bis(hydroxyethyl) isophthalate solution; performing an esterification reaction on terephthalic acid (or dimethyl terephthalate), the ethylene glycol and auxiliaries, then adding a catalyst, a stabilizer, the auxiliaries, the esterification solution of the phosphorus-based flame retardant (or a prepolymer solution of the phosphorus-based flame retardant) and the sulfonate-based bis(hydroxyethyl) isophthalate solution, performing condensation polymerization reaction, and cooling and dicing after the end of reaction to prepare the cationic dyeable flame-retardant polyester resin. The cationic dyeable flame-retardant polyester resin prepared by the method disclosed by the invention has the characteristics of good spinnability, polyester fiber cationic dye boiling dyeing under normal pressure conditions, complete chromatogram and strong dye adhesion.

The invention belongs to the technical field of macromolecular materials, and in particular relates to a preparation method for biodegradable blocked copolyester. The preparation method comprises the following steps: carrying out esterification reaction between adipate and 1,4 butanediol in the presence of catalyst, wherein the reaction time is 3 to 5h, nitrogen is adopted for protection, the reaction pressure is between 0.1 and 0.8MPa and the reaction temperature is between 130 and 180 DEG C during a first stage; and the reaction time is 1.5 to 5h, the reaction pressure is between 0.3 and 0.6MPa and the reaction temperature is between 150 and 200 DEG C during a second stage so as to generate polybutylene adipate; and carrying out ester exchange reaction of dimethyl terephthalate (DMT) and 1,4 butanediol in the presence of catalyst, wherein the nitrogen is adopted for protection, the reaction time is 2 to 5h, the reaction pressure is between 0.1 and 0.7MPa and the reaction temperature is between 150 and 170 DEG C so as to generate polybutylene terephthalate (pbt); and mixing both prepolymers and carrying out melt copolycondensation reaction under negative pressure, wherein the vacuum degree is controlled to be between 0 and 200Pa, the reaction temperature is between 210 and 260 DEG C and the reaction time is 3 to 8h. The preparation method carries out esterification reaction and ester exchange reaction, and the esterification reaction has two stages so as to effectively reduce secondary reaction of 1,4 butanediol. A prepared product has a characteristic viscosity number above 1.2dl/g, a melting point controlled between 100 and 140 DEG C, a tensile strength between 18 and 37MPa and a breaking elongation ratio from 800 to 1,500 percent.

The invention discloses a method for applying a moisture control agent together with dye in the same bath in a fabric dyeing process, which is characterized in that: the dye is added in the fabric dyeing process, and meanwhile the moisture control agent accounting for 0.1 to 5 percent of the weight of the fabric is also added, namely the moisture control agent and the dye are used in the same bath. The moisture control agent comprises the following components in part by weight: 80 to 100 parts of polyethylene glycol, 10 to 15 parts of ethylene glycol, 10 to 14 parts of polyether, 15 to 18 parts of dimethyl terephthalate and 0.2-1 part of metal acetate serving as a catalyst. The method can be widely applied to the dyeing process of the polyester fiber fabric.

The invention relates to a high-temperature leveling agent, and a preparation method and an application thereof. The high-temperature leveling agent is prepared from 0.1-1% of a polyester-polyether-silicon oil block copolymer, 9-10% of polyethylene glycol monostearate, and balance of water. The polyester-polyether-silicon oil block copolymer is prepared from the raw materials of, by weight: 120-160 parts of polyethylene glycol, 18-30 parts of glycol, 15-25 parts of dihydroxy polyether, 20-28 parts of dimethyl terephthalate, 10-30 parts of an amino-terminated double-head sealant organosilicon, 5-10 parts of 3-piperazine propyl dimethoxysilane, and 0.2-2 parts of metal acetate. With the high-temperature leveling agent provided by the invention, dyeing quality of polyester fiber or fabric thereof can be improved, and the dyed polyester fiber or fabric thereof is provided with excellent fluffy and soft property, good antistatic performance, and good hydrophilic property. The dyed polyester or fiber thereof can be provided with excellent comfortableness with no other finishing.

The invention discloses droplet-resistant flame-retardant polyester. The flame-retardant polyester is prepared by random copolymerization of a branched monomer, terephthalic acid or dimethyl terephthalate, ethylene glycol and flame-retardant monomer, wherein the branched monomer is an aliphatic compound or aromatic compound having three or more functional groups; and the flame-retardant monomers adopts any of the following structures. The invention also discloses a method for preparing the droplet-resistant flame-retardant polyester, a nanometer compound material containing the droplet-resistant flame-retardant polyester and a method for preparing the nanometer compound material. Because the droplet-resistant flame-retardant polyester provided by the invention simultaneously contains the branched monomer and the fire retardant having the droplet-resistant effect, the melt viscosity of the droplet-resistant flame-retardant polyester at the high temperature is greatly improved, the sensitivity of the droplet-resistant flame-retardant polyester to temperature is lowered, and the droplet-resistant effect is good; because of the nanometer effect and the blocking effect, the nanometer compound material shows better droplet-resistant effect; and the polyester and the nanometer compound material can be directly used as raw materials for preparing fibers, engineering plastics, films and the like.

The invention discloses a method for preparing a silver-containing PET based composite resin material. In the method, a monomer of terephthalic acid (PTA) or dimethyl terephthalate (DMT) for synthesizing PET and a precursor silver glycol colloid solution are polymerized in situ to prepare the material. The PET/Ag composite resin material prepared by the method has high spinnability and antibacterial property, and the preparation method has smart concept, simple process, short preparation period and low production cost without pollution, and is suitable for large-scale industrial production.

The invention discloses a method for preparing polyester slices for an optical film. The method comprises the following steps of: (1) mixing glycol and dimethyl terephthalate in a pulping kettle to prepare a slurry solution, putting glycol and a catalyst in a catalyst preparation kettle to prepare a catalyst solution, and putting nanoscale additives and glycol into an additive preparation kettle to prepare an additive solution; (2) putting the slurry solution and the catalyst solution in an esterifying kettle and heating to carry out ester exchange reaction so as to obtain an esterified matter; (3) pressing the esterified matter and the additive solution in a pre-polycondensation kettle, vacuumizing during the process of pre-polycondensation reaction, discharging superfluous glycol; and (4) pressing the product of the pre-polycondensation into a final polycondensation kettle to increase the viscosity of a fusant, and cooling and pelleting the fusant to obtain the polyester slices for the optical film. According to the method for preparing the polyester slices for the optical film, disclosed by the invention, the difficult problem of dispersivity of the nanoscale additives is solved, meanwhile, the phenomenon of sand-granular fogging of an ordinary polyester film is overcome, the fogging degree of the film is lowered, and the high light transmittance of the polyester film is ensured.

This invention discloses a method for preparing dimethyl 1,4-cyclohexane dicarboxylate by hydrogenation of dimethyl terephthalate in solvent in the presence of catalyst. The solvent is water or C1-4 fatty alcohol. The catalyst (80-200 mesh) is composed of Ru (0.5-10 wt. %) as the active component, and Al2O3 as the carrier. The weight ratio of dimethyl terephthalate to the solvent is 1: (0.5-10), while that of the catalyst to dimethyl terephthalate is 1: (5-20). The reaction is performed at 120-180 deg.C under 1.0-5.0 MPa for 0.5-8.0 h. Compared with present techniques, the method has such advantages as mild hydrogenation conditions, short hydrogenation time and long catalyst service time (recycleable for more than 9 times).

Disclosed is a process for producing copolyesters with high levels of recycled content. Scrap or post-consumer poly(ethylene terephthalate) is depolymerized by methanolysis or glycolysis to produce a purified, recycled dimethyl terephthalate which can be repolymerized with 2 or more diols. The polyesters of this invention have physical properties and an appearance that is similar to polyesters prepared from virgin monomers. In addition to dimethyl terephthalate, the polyesters can be prepared from recycled ethylene glycol recovered from depolymerization of poly(ethylene terephthalate) and/or 1,4-cyclo-hexanedimethanol prepared by hydrogenation of recycled dimethyl terephthalate or recovered from depolymerized polyester mixtures.

The invention relates to a fluffy and soft finishing agent used in polyester fiber, and a preparation method thereof. The agent comprises the following components, by weight: 120-160 parts of polyethylene glycol, 18-30 parts of glycol, 15-25 parts of dihydroxy polyether, 20-28 parts of dimethyl terephthalate, 10-30 parts of an amino-terminated double-head sealant organosilicon, 5-10 parts of 3-piperazine propyl dimethoxysilane, and 0.2-2 parts of metal acetate as a catalyst. The polyester fiber fluffy and soft finishing agent is a polyester-polyether-silicone oil block copolymer produced through a reaction with the raw materials and with a number average molecular weight of 8000-20000. When the polyester fiber provided by the invention is used for finishing polyester, the polyester fiber is provided with extremely fluffy and soft texture. Also, polyester fiber antistatic property and hydrophilic property can be improved. Therefore, the comfortableness of the modified polyester fiber can be greatly improved. Also, the cost of the polyester fiber provided by the invention is low.

The invention provides a method for depolymerizing waste polyester, which comprises the following steps of: adding methanol and cosolvent gas into a reaction system and utilizing the methanol and the cosolvent gas for depolymerizing waste polyester-polyethylene glycol terephthalate material so as to obtain dimethyl terephthalate and ethylene glycol on thesupercritical condition. According to the invention, as the cosolvent is added, the depolymerizing reaction temperature of the waste polyester is lowered and the reaction time is shortened, thereby reducing the energy consumption. As the cost of the cosolvent is relatively lower and easy for recycling, the recycling cost of the waste polyester is further lowered. In the method, the degradation rate of the olyethylene glycol terephthalate is more than 99.9 percent, the monosomic selectivity is high, and the content of oligomers in the product is low.

The invention belongs to the technical field of catalysts and particularly relates to a low-content supported ruthenium-palladium bimetal hydrogenation catalyst and a preparation method thereof. The preparation method of the catalyst comprises the following steps: preparing a ruthenium monometal solution and a palladium monometal solution; under ultrasonic conditions, supporting the two active components (ruthenium and palladium) of the metal catalyst on the surface of an aluminum oxide carrier by respectively adopting a co-impregnation method and a fractional impregnation method; and washing, drying, roasting, and performing other treatment processes to finally obtain the low-content supported ruthenium-palladium bimetal hydrogenation catalyst. According to the invention, the method is low in cost; and the prepared bimetal hydrogenation catalyst has high selective hydrogenation activity, and shows excellent catalytic activity, favorable catalytic stability and high 1,4-cyclohexanedicarboxylic acid dimethyl ester (CHDM) yield when being used in the reaction process of preparing CHDM through selective hydrogenation of dimethyl terephthalate.

The invention provides a processing method for alkali-minimization wastewater, comprising a plurality of steps: (a) adjusting the PH value of alkali-minimization wastewater into 6.5 to 7, using the method of acid precipitation to obtain liquid phase and the solid phase with terephthalic acid; (b) carrying out esterification reaction for the solid phase from the procedure (a) in the presence of methanol to obtain a crude dimethyl terephthalate product. The method recovering terephthalic acid from alkali-minimization wastewater makes CODcr value of the wastewater removal of more than 75% and modifies the wastewater into Biodegradable industrial wastewater and at the same time changes the phthalic acid into dimethyl terephthalate.

The invention discloses a method for synthesizing C-level polyurethane wire enamel. The C-level polyurethane wire enamel prepared by the method has high heat-resistant performance and solderability and physical performance, and the heat-resistant level reaches a C level. The method for synthesizing the C-level polyurethane wire enamel mainly comprises the following steps of: synthesizing polyester polyol, synthesizing a diphenylmethane diisocyanate (MDI) tripolymer and preparing polyurethane paint, wherein the polyester polyol is prepared by reacting dimethyl terephthalate, tri-(2-ethoxy) isocyanurate and dihydric alcohol which serve as raw materials under the action of a catalyst; and the dihydric alcohol is N-methyldiethanolamine, and part of dimethyl terephthalate is replaced by addingtetracarboxylic dianhydride for reaction.

The invention discloses a process of recovering terephatalic acid from colored alkali reduction waste water, processing two waste water streams thick and thin coming from alkali reduction process by qualities, firstly decolorizing by decolorizing agent, then integrating acid precipitation with diaphragm process to recover erephatalic acid from the waste water, thus making CODcr of waste water reduced by 50-70% for the convenience of follow-up biochemcial and physical chemcial treaments, where the purity of the recovered terephatalic acid is up to above 90%, able to act as chemcial raw material for preparing dimethyl terephthalate, and dioctyl terephthalate. And it can be applied to chemcial production, controlling pollution, improving environment, saving energy sources, reducing cost, and obtaining good economic and environmental benefits.

The invention provides a process for producing a variety renewable aromatic compounds such as benzene, toluene, xylenes, and cumene, as well as compounds derived from these including, for example, aniline, benzoic acid, cresol, cyclohexane, cyclohexanone, phenol and bisphenol A, toluene di-isocyanate, isophthalic acid, phthalic anhydride, terephthalic acid and dimethyl terephthalate. The invention also provides for renewable forms of these aromatic compounds.