142 results about "Trans esterification" patented technology

The application discloses a kind of heat-conducting, wave-absorbing, insulating, high tough rubber composite material and its preparation method and application, it is related to rubber material technical field.The application is prepared into masterbatch by step preparation of epoxidized modified rubber and carboxylated modified rubber after mixing, wherein esterification reaction of carboxyl group and epoxy group and ester exchange reaction of generated dynamic covalent bond realize the dynamic crosslinking of epoxidized modified rubber and the combination with carboxyl rubber, give composite material high tough mechanical property;Selective dispersion of functional filler in isolated double network structure avoids mutual interference between them, realizes the synergistic improvement of heat-conducting, wave-absorbing, insulating performance;Based on volume repulsion effect, filler forms enrichment in the phase, and the composite material can realize high heat-conducting and wave-absorbing performance under low total amount of filler.

The present invention relates to a bismuth-containing catalyst of formula (R1)2-(R2)-(Bi)3+ (I), wherein (R1)2- is a dianion of formula (II*), wherein A is unsubstituted or at least monosubstituted linear C3-30-alkylene, wherein at least two not adjacent CH2 groups of C3-30-alkylene are replaced by a heteroatom independently selected from the group consisting of O, S, 5 NH, N-C1-30-alkyl, N-C6-14-aryl and N-C7-30-aralkyl, wherein alkyl and aryl fragments of N-C1-30-alkyl, N-C6-14-aryl, N-C7-30-aralkyl may at least be monosubstituted by hydroxyl, halogen, -CF3, NH2, -NH-C1-6-alkyl, -NH- phenyl, -N(C1-6-alkyl)2, -N(phenyl)2, -SH, -S-C1-6-alkyl, -S-phenyl, -O-C1-6-alkyl or -O-phenyl, to process for the preparation of the bismuth containing catalyst, to a process for the preparation of a compound, oligomer or polymer comprising at least one urethane group using the bismuth-containing catalyst, to a composition comprising (i) at least one monoalcohol (B1) or polyol (B2), (ii) at least one polyisocyanate (A) and (iii) the bismuth-containing catalyst, to a coating or adhesive layer formed from the composition on a substrate, to a foam formed from the composition, and to the use of the bismuth-containing catalyst in for preparing compounds, oligomers or polymers comprising a urethane group, as esterification and transesterification catalyst and as catalyst for ring-opening polymerizations of lactones and epoxides.

This invention discloses a potassium nepheline precursor and its dispersion, a potassium nepheline catalyst, its preparation method, and its applications. The potassium nepheline precursor of this invention has an amino-containing silane coupling agent grafted onto its surface. The potassium nepheline precursor dispersion of this invention comprises a potassium nepheline precursor and a dispersion medium, wherein the average diameter of the potassium nepheline precursor in the dispersion is 5–20 nm. The potassium nepheline catalyst prepared using the potassium nepheline precursor dispersion of this invention exhibits high activity and good stability when used in transesterification reactions to produce biodiesel.

This invention discloses a method for preparing a composite alcohol-base catalyst suitable for transesterification reactions, relating to the fields of catalyst preparation technology and organic synthesis technology. This invention uses anhydrous alcohol phase in-situ alcoholization reaction treatment to make the catalyst surface cleaner, reduce the impact of impurities on catalyst activity, and enhance the structural stability of the catalyst. This catalyst can maintain high catalytic activity after multiple uses, extending the catalyst's service life and reducing production costs.

A method for producing a (meth)acrylate monomer of a polyalkoxylated alcohol includes providing an unneutralized polyalkoxylated alcohol, wherein the unneutralized polyalkoxylated alcohol is produced by base catalyzed alkoxylation. An alkyl (meth)acrylate is transesterified with the unneutralized polyalkoxylated alcohol to produce the (meth)acrylate monomer of the polyalkoxylated alcohol. No transesterification catalyst is added during the step of transesterifying the alkyl (meth)acrylate with the unneutralized polyalkoxylated alcohol.

The present invention relates to mutants of the bumblebee Yarrowia SBLE enzyme having modulated transesterification and / or esterification activity compared to the bumblebee Yarrowia SBLE enzyme, and to homologues of the bumblebee Yarrowia SBLE enzyme, such as the C. bogoriensis LE enzyme, the B. batistae LE enzyme and the R. riograndensis LE enzyme, having transesterification and esterification activity on bolaform glycolipids. The present invention also provides genetically modified yeast strains comprising a mutant LE enzyme or a bumblebee Yarrowia SBLE enzyme homologue of the present invention. The present invention further provides the use and methods of the mutant LE enzymes, the bumblebee Yarrowia SBLE enzyme homologues and the modified yeast strains of the present invention for the production of acidic glycolipids, lactone-form glycolipids and / or glycolipid oligomers / polymers / esters. The present invention also provides the three-dimensional structure of the bumblebee Yarrowia SBLE enzyme and its use for the design of mutants having modulated hydrolysis and / or transesterification activity.

This invention relates to a method for preparing a capped polycarbonate resin, comprising the steps of: a) reacting a dihydroxy compound and a carbonate in a melt, optionally in the presence of an transesterification catalyst, thereby forming a polycarbonate in a molten phase having free hydroxyl terminal groups; and b) reacting the polycarbonate in the molten phase with a capping agent to produce a capped polycarbonate resin, wherein the capping agent comprises an anhydride, and wherein the polycarbonate in the molten phase is subjected to at least partially vacuum after being combined with the capping agent. The invention also relates to capped polycarbonate resins obtained or obtainable by this method. Furthermore, the invention relates to molding articles comprising or composed of such capped polycarbonate resins, and methods for manufacturing such molding articles.

The application provides a kind of bio-based polyol and its preparation method and application.The preparation method contains the following steps: mixing alcohol with catalyst, adding epoxy soybean oil to react, removing catalyst and VOC after treatment, adding epoxide, natural oil and small molecule polyol reaction and ester exchange.The application adjusts the viscosity, functionality and molecular weight of the product through specific ester exchange reaction, and improves the compatibility of the product by adding epoxide, so that it can meet the needs of various applications.The bio-based polyether polyol synthesized by the method has good performance effect in soft foam, slow rebound and CASE field.

The application discloses a kind of deformation-resistant thermoplastic composite material and preparation method thereof, belong to high polymer composite material preparation technical field, to solve the existing thermoplastic composite material under high load prone to creep, fiber infiltration is insufficient and the problems such as insufficient part size stability.The application uses cyclic butylene terephthalate oligomer as low-viscosity precursor, introduces bifunctional catalytic crosslinking agent, and carries out in-situ reactive molding with glass fiber reinforcement.The method utilizes the low melt viscosity of cyclic butylene terephthalate oligomer, realizes the sufficient infiltration of fiber reinforcement before polymerization and viscosity increase, and constructs a covalent crosslinking network containing dynamic ester exchange bond in-situ during ring-opening polymerization.The obtained composite material has low porosity and good interface bonding, and significantly improves the anti-creep performance and dimensional stability while maintaining the toughness of thermoplastic materials.

This invention discloses a method for preparing a high-barrier biodegradable material, comprising the following steps: A) Raw material pretreatment: Drying solid raw materials separately in a vacuum drying oven at 60-80℃ for 6-12 hours until the moisture content is below 0.05%; B) Melt blending: Mixing the dried raw materials with the remaining raw materials in a specific ratio until homogeneous. This invention significantly improves the barrier properties of the material through the synergistic effect of benzyl glycidyl ether, transesterification modified monomers, 1,4-succinic acid, nano-montmorillonite, and epoxy-modified graphene oxide. A balanced mechanical property is achieved through the rational ratio of polylactic acid and polybutylene adipate-terephthalate, as well as the effects of catalysts, chain extenders, and compatibilizers. The material achieves a degradation rate of 85.2% within 90 days, exhibiting good biodegradability and meeting environmental protection requirements. Through an optimized melt blending process, the material possesses good processing performance and can be molded using conventional plastic processing equipment, facilitating industrial production.

Disclosed is a novel room-temperature curable bio-based epoxy vitrimer with a simple design of the chemical structure. A hempseed oil-derived glycidyl ester type epoxy (HOEP) was synthesized and then blended with a bisphenol A epoxy (DER331) to manipulate the properties of the resulting vitrimer s. An aliphatic amine hardener, diethylenetriamine (DETA), was selected as hardener to realize the room temperature curing in presence of triethanolamine (TEOA) as the catalyst. Unlike the traditional glycidyl ether epoxy-amine the thermosets which are based on sable C—N and ether linkages, the epoxy vitrimer herein includes ester bonds with HOEP and hydroxyls formed from the reaction of amine and epoxy in its cross-linked network. Dynamic transesterification (DTER) between the ester bonds and hydroxyls take place at elevated temperatures, imparting the vitrimer significant stress relaxation behavior and repairability. This provided a viable method to produce room temperature curable epoxy vitrimer s.

The application discloses a process for producing diacylglycerol oil by an enzyme method in a solvent-free system, and comprises the following steps: taking low-cost lipase as a catalyst, preparing lipase A by immobilization of the enzyme, preparing lipase B by an ester exchange reaction, and then taking the lipase B as a catalyst to catalyze esterification of free fatty acid and monoglyceride in a solvent-free system to prepare diacylglycerol oil.

The application discloses an enzymatic production process of diglyceride, and comprises the following steps: using low-cost lipase as a catalyst, preparing lipase A through immobilization of the enzyme, preparing lipase B through an ester exchange reaction, and then using the lipase B as a catalyst to catalyze esterification of free fatty acid and glycerol to produce diglyceride; the method can realize efficient enzymatic production of diglyceride through a series of methods by using low-cost lipase, and the production cost is reduced. The application provides an economical and efficient method for producing diglyceride by using the enzyme method, greatly reduces the use cost of lipase in the enzymatic esterification reaction, and has certain industrialization application prospect.

This invention discloses an aging-resistant glass fiber for sheet materials and its preparation method, relating to the field of polymer materials technology. The preparation method of the aging-resistant glass fiber for sheet materials includes the following processes: uniformly grinding glass raw materials into powder, melting, drawing into fibers, coating with a reinforcing sizing agent, cooling, and winding to obtain glass fibers. This invention modifies palm oil through alkali-catalyzed transesterification, replacing the glycerol ester groups in palm oil to form single-chain fatty acid methyl esters, reducing branching, lowering the viscosity and molecular weight of palm oil, allowing it to be more uniformly dispersed in the glass fibers, and enhancing the glass fibers' resistance to atmospheric moisture erosion; it also modifies the silane coupling agent to contain both vinyl and amino groups in its structure, enhancing the bonding strength between the glass fibers and the reinforcing sizing agent, further improving the weather resistance, mechanical strength, and high-temperature resistance of the glass fibers.

Processes for transesterifying wax esters. Implementations may include: providing a feedstock including wax esters, contacting the feedstock with a lipase, and catalytically transesterifying the wax esters in the feedstock with the lipase to form a transesterified product. An oxidative stability index (OSI) of the transesterified product may be greater than an OSI of the feedstock.

This application discloses a bio-based polyether polyol suitable for supercritical carbon dioxide-assisted foaming, its preparation method, and a rigid polyurethane foam using the same, belonging to the field of polyurethane technology. This application uses vegetable oil as raw material and obtains a bio-based polyol suitable for scCO2-assisted foaming through alcohol (amine) ester exchange, free radical Pudovik reaction, and epoxide anion ring-opening reaction. This polyol also possesses intrinsic flame-retardant properties. While using scCO2-assisted foaming, it eliminates the need for adding non-environmentally friendly physical foaming agents, and the main component of the raw material is biomass-derived vegetable oil, offering advantages such as green environmental protection and low cost, making it suitable for industrial-scale application.

Processes for transesterifying wax esters. Implementations may include: providing a feedstock including wax esters, contacting the feedstock with a lipase, and catalytically transesterifying the wax esters in the feedstock with the lipase to form a transesterified product. An oxidative stability index (OSI) of the transesterified product may be greater than an OSI of the feedstock.

The present invention relates to the manufacturing of alkyl (meth)acrylate by transesterification catalysed by one or more chemical species that precipitate upon contact with water. More specifically, it relates to an improved process for manufacturing alkyl (meth)acrylate, leading to a high yield of a product that meets purity standards, and comprising a step of reusing the heavy by-products generated during this manufacture owing to a step of thermal and catalytic cracking, generating recycled reagents in the process as well as methane and mineral salts obtained by hydrothermal gasification of this cracking residue alone, mixed with the residues of other alkyl esters or with alcohols.

This invention relates to the field of additive manufacturing materials technology, and in particular to a method for improving the interlayer bonding strength of 3D printed materials based on dynamic crosslinking, as well as the resulting molded components and applications. The raw material composition includes 100 parts of thermoplastic polymer, 1-10 parts of epoxy-grafted monomer, 0.05-0.5 parts of initiator, 1-8 parts of crosslinking agent, and 0.1-3 parts of transesterification catalyst. This invention solves the problems of low Z-axis strength, severe anisotropy, difficulty in maintaining the molded morphology during post-processing, and severe warping deformation in thermoplastic 3D printed products. It overcomes the current situation where existing dynamic covalent bond (glass-like) modification technologies mostly rely on UV curing or liquid resin precursors. Simultaneously, it overcomes the technical challenge of extending dynamic crosslinking technology to the melt deposition and molten particle manufacturing processes of thermoplastic polymers such as polyolefins and thermoplastic polyurethanes.

This invention discloses an isosorbide-based polycarbonate with a controllable glass transition temperature and its preparation method. The preparation method includes: subjecting isosorbide, hydrogenated bisphenol A, and carbonate diester to at least a transesterification reaction and a polycondensation reaction in the presence of a catalyst to obtain the isosorbide-based polycarbonate with a controllable glass transition temperature. This invention can improve the toughness and processability of isosorbide-based polycarbonate, enhance its UV resistance, and give it a controllable glass transition temperature.

The application discloses a kind of PBAT composite film and preparation method thereof, the PBAT composite film includes following raw materials, PBAT resin, calcium carbonate, optional PLA and optional other auxiliary agent, wherein, the preparation method of the PBAT resin includes following steps: (1) short straight chain aliphatic dibasic acid is esterified with short branched-chain aliphatic dihydric alcohol, and polyester oligomer A is obtained;(2) adipic acid, terephthalic acid and 1,4-butanediol are esterified and polycondensed, and polyester oligomer B is obtained;(3) polyester oligomer B is added to polyester oligomer A to carry out ester exchange reaction, and PBAT resin is obtained.The application can significantly improve the molecular chain movement ability by reacting with aliphatic polyester oligomer during PBAT polymerization, so that the glass transition temperature and crystallinity of PBAT are significantly reduced, so as to improve the heat sealing effect of composite film.

This invention relates to the field of textile manufacturing technology, specifically to a method for preparing polyester fibers for automotive interior carpets by stretching. The method includes steps such as crosslinking modifier preparation, modified spinning melt formulation, low-temperature orientation stretching, high-temperature reactive stretching, and relaxation heat setting. The method combines polyester chips with a terminal hydroxyl hyperbranched multifunctional polysiloxane crosslinking modifier to covalently anchor flame-retardant and antistatic segments within the polyester macromolecular network. The key technology of this invention lies in the activation of titanium acetylacetonate during the high-temperature stretching stage, which promotes an ester exchange crosslinking reaction between the terminal hydroxyl groups of the modifier and the ester bonds of the polyester molecular chains, constructing chemical crosslinking points in situ under the stretched orientation state. This invention overcomes the defects of traditional physical blending agents, such as stress concentration, high breakage rate, and easy loss of function. By utilizing the orientation-crosslinking structure, it effectively prevents molecular chain slippage under pressure, effectively improving the irreversible deformation problem of carpets under long-term cyclic compression loads, and ensuring the fiber's durable high compression resilience, flame retardant, and antistatic properties.

This invention belongs to the field of polymer material preparation, specifically relating to an aqueous phase-guided self-assembly composite catalyst and a method for preparing polycarbonate. Addressing the problems of poor dispersibility and unstable active centers of inorganic co-catalysts in organic melts in existing technologies, this invention provides an aqueous phase-guided self-assembly composite catalyst. This composite catalyst possesses an ion cluster with a microstructure of "lipophilic quaternary phosphonium shell – hydration layer – inorganic core." When applied to the melt transesterification method for preparing polycarbonate, this catalyst utilizes the vaporization and expansion of water in the high-temperature melt to achieve "nano-bursting" dispersion of inorganic components, effectively solving the problems of poor dispersion and easy agglomeration of traditional inorganic co-catalysts. This system combines high activity at low temperatures with high-temperature stability, significantly shortening the polymerization time, and the resulting polycarbonate product has a narrow molecular weight distribution and an extremely low yellowness index (YI≤2.4), making it suitable for the efficient preparation of bisphenol A type and various copolymer polycarbonates.

This invention relates to the field of crystal materials technology, specifically disclosing a wear-resistant and antibacterial composite leather for electronic skin and its preparation method. The composite leather is composed of delimed bare leather, plant polyphenols, glutaraldehyde, lysine-chitosan graft polymer, tannic acid-zirconium coordination oligomer solution, plant-derived wax esters, and lipase. The preparation method includes: adding plant polyphenols and glutaraldehyde to the delimed bare leather for tanning to obtain primary cross-linked raw leather; adjusting the pH and then adding lysine-chitosan graft polymer and tannic acid-zirconium coordination oligomer for an antibacterial mineralization reaction; then adding plant-derived wax esters and lipase for an enzyme-catalyzed transesterification reaction; finally, drying, rehydrating, and softening to obtain the finished product. This invention, through the synergistic effect of multi-stage processes including composite tanning, synergistic antibacterial action, and enzyme-catalyzed lubrication, enables the composite leather to possess excellent wear resistance, long-lasting antibacterial properties, high breathability, and good softness, making it suitable for wearable devices such as electronic skin and showing promising application prospects.

The application discloses a kind of multi-stage distillation filtration methods and systems of diphenyl monoisodecyl phosphite production, it is related to diphenyl monoisodecyl phosphite production and processing technical field, including the following steps: the ester exchange reaction after the crude product containing diphenyl monoisodecyl phosphite is carried out first thin film evaporation and is light, and the light component in the crude product after ester exchange reaction is separated out;The crude ester product after light removal is carried out secondary vacuum rectification treatment, and high-purity diphenyl monoisodecyl phosphite fraction is obtained;High-purity diphenyl monoisodecyl phosphite fraction is carried out third filtration purification treatment, and final product is obtained;By establishing the whole process integrated mathematical model covering thin film evaporation, vacuum rectification and filtration, system can real-time perception feed fluctuation, and each level process parameter is dynamically adjusted in advance, ensure that impurities are removed accurately and efficiently, effectively eliminate the product quality batch fluctuation caused by parameter fixed or adjustment lag under traditional mode.