33results about "Esters preparation by oligomerisation" patented technology

The invention provides a polycondensation catalyst for producing polyester by an esterification reaction or a transesterification reaction between a dicarboxylic acid or ester-forming derivative thereof and a glycol, wherein the polycondensation catalyst comprises particles of a solid base having on their surfaces either a coat layer of titanic acid in an amount of from 0.1 to 50 parts by weight in terms of TiO₂ per 100 parts by weight of the solid base, or an inner coat layer of an oxide of at least one element selected from silicon, aluminum and zirconium or a composite oxide of at least two elements selected from silicon, aluminum and zirconium in an amount of from 1 to 20 parts by weight per 100 parts by weight of the solid base and an outer coat layer of titanic acid in an amount of from 0.1 to 50 parts by weight in terms of TiO₂ per 100 parts by weight of the solid base

The invention provides a modified acrylic acid oligomer, which comprises polymerizing units derived from the following monomers, (1) acrylic monomers, (2) monomers of fluoride acrylic monomers, silicone monomers or the mixture of the two, and (3) three-grade carboxylic ester monomers which depend; wherein, the oligomer also comprises groups of modifier which consists of epoxy acrylate, amidine formic ester acrylate, polyester acrylate, methacrylic 2-hydroxyethyl ester and the mixture; the modified acrylic acid oligomer also provides an antipollution coating containing the modified acrylic acid oligomer.

The invention discloses a synthetic method of a brush type homopolymer and a brush type copolymer containing conjugate oligomeric branched chains. In the synthesis process of a novel monomer, a metal catalysis coupling reaction and an esterification reaction are adopted, so that conjugate alkene monomers such as oligo-containing polyfluorene, oligomeric benzene, oligomeric benzyne, oligomeric carbazole, oligomeric thiophene and the like are synthesized; and a way for grafting and grafting to is adopted, and radical polymerization (including atom transfer radical polymerization) are performed, so that a series of brush type homopolymers and copolymers with conjugate branched chains are obtained, homopolymerization, binary irregular copolymerization and block copolymerization, and ternary irregular copolymerization and block copolymerization of a monomer containing a conjugate branched chain are realized, and special brush type homopolymers and brush type copolymers are obtained. The synthetic method disclosed by the invention is simple, convenient and practicable; a synthesized brush type polymer has a controllable structure; and a three-dimensional structural design of a large molecular strain is realized, and combination of a conjugate structure and a brush type structure is realized, so that a polymer with excellent comprehensive performance is obtained.

A lactic acid based by-product formed in a process of producing a lactic acid based composition is subjected to racemization in the presence or absence of a catalyst to thereby obtain a lactic acid component having substantially optical inactivity. Then, lactide or polylactic acid having optical inactivity can be obtained from the lactic acid component having the optical inactivity. The obtained lactide or polylactic acid is mixed with lactide or polylactic acid having an optical purity in a range of 90 to 100% e.e. at a predetermined ratio to thereby obtain lactide or polylactic acid having a desired optical purity.

Provided herein are processes for preparing estolides and estolide base oils from fatty acid reactants utilizing catalysts. Further provided herein are processes for preparing carboxylic esters from at least one carboxylic acid reactant and at least one olefin.

A preparation method of a conjugated diene and polar monomer segmented copolymer with low molecular weight belongs to the field of copolymer synthesis. The method can solve the problem that the existing conjugated diene and polar monomer copolymer is high in molecular weight and preparation cost. The method comprises the steps of adding a reaction monomer and a catalyst to an alkane solvent according to the molar ratio of (100-2000):1 for reaction to obtain a solution a, adding the polar monomer to the obtained solution a to obtain a solution b, adding alcohol solution to the obtained solution b with the molar ratio of the polar monomer to the catalyst of (10-800):1, and condensing the conjugated diene and polar monomer segmented copolymer. For the synthesized conjugated diene and polar monomer segmented copolymer, the number-average molecular weight is 1.2*10<3>-25.0*10<3>, and the molecular weight distribution is 1.20-1.50.

A novel flaky catalyst for synthesizing a dimmer acid ester consists of activated clay, a promoter and an adhesive pore-forming agent, wherein the activated clay accounts for 65-85 percent, the promoter accounts for 2-10 percent, and the adhesive pore-forming agent accounts for 13-25 percent. The preparation method for the catalyst comprises the following steps of: preparing the powder of the activated clay with a particle size of 150-250 meshes; mixing the raw materials evenly according to the partition ratio; tabletting and forming; drying the mixture at 105 DEG C; calcining the mixture at 300-400 DEG C; and cooling down and packaging the mixture. The method is simple and feasible. The catalyst which has good activity and high strength is easy to be separated from products with less products carried. In addition, the catalyst is easy to be regenerated.

The present invention related to compositions and methods of producing polyesters with two and/or more different structural units and the materials of polyesters with structure sequence exactly specified therefore produced, and various articles produced from such exactly sequenced polyesters. More particularly, homogeneous copolymers with precisely defined sequences of various hydroxyl acids and their derivatives are produced according to the present invention.

A method for producing a multisubstituted biphenyl compound represented by general formula (2), said method comprising a step for coupling a substituted benzene compound represented by general formula (1) in the presence of a solid catalyst wherein gold is fixed on a support.

A method is provided for producing a compound, including a step of mixing a compound (1) having one or two leaving groups, a compound (2) having one or two boron atom-containing leaving groups, an organic base (P), and at least one selected from a phase transfer catalyst and an organic base (Q) larger in the number of carbon atoms than the above-mentioned organic base in the presence of a transition metal catalyst. The method thereby performs a coupling reaction between the above-mentioned compound (1) and the above-mentioned compound (2).

The invention provides (meth)acrylic oligomers prepared from C1-C20 alkyl and C5-C20 cycloalkyl (meth)acrylates, wherein said oligomers have a Mn of about 300 g/mole to about 3,000 g/mole; a Mw of about 700 g/mole to about 6,000 g/mole; a Mz of about 900 g/mole to about 10,000 g/mole. The oligomers may have a Yellowness Index, according to ASTM E313 of less than 2. The oligomers of the invention are useful as tackifiers in adhesive compositions, but also are believed to be useful also in general polymer modification as plasticizers, leveling agents, viscosity reducers (i.e., rheology modifiers), and for increasing solids content in solvent-borne applications of all types with little detrimental impact on viscosity. The invention also provides adhesive compositions and laminate articles coated on at least one side with the adhesive compositions of the invention.

Disclosed herein are compounds and compositions useful for reducing the risk of infection. In particular, disclosed herein are mandelic acid condensation polymers, compositions comprising such compounds, processes for producing such compounds, and methods of using such compounds.

The present invention relates to a method of manufacturing norbixin or bixin ethyl ester, which is a carotenoid-based compound, from a novel intermediate compound. When the novel intermediate compound is used, it is possible to manufacture norbixin or bixin ethyl ester in high yield through a simple process.

A process to prepare a (iv) cyclic polyester oligomer composition includes a cyclic polyester oligomer having furanic units and two to five repeat units. The process includes (a) reacting a monomer composition including: (i) a bifunctional furan-derivative and (ii) a diol in an linear oligomerization step to produce a (iii) linear oligomer composition including a linear oligomer species, (b) reacting the (iii) linear oligomer composition in a distillation-assisted cyclization (DA-C) step to form a (iv) cyclic polyester oligomer composition and a (v) diol byproduct. The (v) diol byproduct is removed by evaporation in the distillation-assisted cyclization (DA-C) step.