2384 results about "Isophthalic acid" patented technology

A luminescent solar collector is provided comprising a substrate and a light energy converter, such as a photocell, operatively connected thereto. The substrate is molded from a thermoplastic composition comprising a polymer and a fluorescent dye or quantum dot dispersed therein. The polymer comprises a polycarbonate unit and a polyester unit derived from the reaction of isophthalic acid, terephthalic acid, and resorcinol (ITR). In further embodiments, the substrate comprises two or more layers including a fluorescent layer and an overcoat layer. The fluorescent layer comprises the fluorescent dye or quantum dot and a polycarbonate polymer. The overcoat layer comprises the ITR unit. The substrate, in single layer or multiple layer form, has reduced haze levels over a prolonged period of time.

The invention discloses a method for preparing continuous polymerization directly-spun high-shrinkage polyester filaments, which comprises a process for preparing continuous polymerization modified copolyester melt and a process for preparing directly-spun cation-dyeable high-shrinkage polyester filaments. In the process for preparing the continuous polymerization modified copolyester melt, purified terephthalic acid, isophthalic acid and glycol monomers are taken as raw materials to prepare the modified copolyester melt; and the copolyester melt directly passes through a melt conveying piping equipment, and is metered, extruded, blown to be cooled, drawn for heat shaping, and wound to prepare one of high-shrinkage polyester preoriented yarns and high-shrinkage polyester drawn yarns. The method has the advantages of short flow, less working procedures, reasonable process, stable melt quality, and good spinning performance; and the prepared high-shrinkage fibers have good shrinkage stability and even dyeing, and the production cost is reduced obviously.

Transparent polyamide molding materials are provided which are characterized in that they have a melting enthalpy between 0 and 12 J/g and the polyamides are constituted of

100 mole-% of a diamine mixture having 10-70 mole-% of PACM [bis-(4-amino-cyclohexyl)-methane] with less than 50 wt.-% of trans,trans-isomer and 90-30 mole-% of MACM [bis-(4-amino-3-methyl-cyclohexyl)-methane], wherein, optionally, 0-10 mole-% can be replaced by other aliphatic diamines having 6 to 12 C atoms, cycloaliphatic, alkyl-substituted cycloaliphatic, branched aliphatic diamines or multiamines having 3 to 12 amino groups or mixtures thereof, and

100 mole-% of long-chain aliphatic dicarboxylic acids having 8 to 14 C atoms or mixtures of these dicarboxylic acids, wherein 0-10 mole-% can be replaced by other aromatic or cycloaliphatic dicarboxylic acids having 8 to 16 C atoms, which are especially selected from the group consisting of isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, cyclohexanedicarboxylic acid or mixtures thereof, and

wherein, optionally, 0-10 mole-% of the other long-chain aliphatic diamines and 0-10 mole-% of the other long-chain aliphatic dicarboxylic acids can be added as 0-20 mole-% of ω-aminocarboxylic acids having 6 to 12 C atoms or lactams having 6 to 12 C atoms.

Further, methods for producing the polyamide moulding materials and methods for producing and further treating moulded articles from the polyamide moulding materials are provided. Especially, the present invention relates to glasses and lenses which are obtainable from the polyamide moulding materials.

The invention discloses a preparation method of polyol copolyester. The preparation method comprises the following steps of carrying out slurry preparation, esterifying I, esterifying II, pre-condensing I, pre-condensing II, final condensing and pelletizing on terephthalic acid and glycol. The preparation method also comprises: carrying out ester exchange reaction on 1,3-isophthalic acid-5-sodium sulfonate and another polyol; diluting with the glycol, and then performing the esterifying II. In the preparation method, 1,3-isophthalic acid-5-sodium sulfonate and another polyol react in advance, thereby increasing the reaction probability of another polyol and ensuring that another poyol can reach the required mole ratio in a finished product. The preparation method is mainly applied to production of dye modified polyester by using various dihydric alcohols at normal temperature and normal pressure. The modified polyester is dyed by mainly using anode pigment, the used dye chromatograph is more than that of common polyester, dye-uptake rate can reach above 99%, colour fastness reaches 4-5 grade of European standard, and the color is more flamboyance and beautiful. When filament yarns are subjected to spinning, full-package rate is up to 95%-100%.

An aromatic dicarboxylic acid is purified by oxidizing m-xylene or p-xylene to produce crude isophthalic acid or crude terephthalic acid, respectively. The products of the oxidizing step are hydrogenated in the presence of a palladium catalyst. Carbon monoxide is introduced during the hydrogenation step. The palladium catalyst is provided on a carbon substrate. The products of the oxidizing step are dissolved in a solvent, which may be water, prior to the hydrogenation step. The products of the oxidizing step may be dissolved at an elevated temperature, above the normal boiling point of the solvent. The oxidation step produces isophthalic acid, 3-carboxybenzaldehyde and fluorenones in the case of oxidizing m-xylene and produces terephthalic acid, 4-carboxybenzaldehyde and fluorenones in the case of oxidizing p-xylene. It may be helpful to monitor the disappearance of 3-carboxybenzaldehyde in the case of oxidizing m-xylene and 4-carboxybenzaldehyde in the case of oxidizing pxylene, and reducing the amount of carbon monoxide when the rate of disappearance is below a predetermined minimum. After the hydrogenation step, the isophthalic acid or terephthalic acid may be crystallized. The carbon monoxide may be maintained at a concentration of 100 to 500 ppm based on added hydrogen and carbon monoxide. Other aromatic dicarboxylic acids may also purified by this procedure.

The invention discloses aqueous acrylic acid-modified alkyd resin and a preparation method thereof. Basic alkyd resin of the aqueous acrylic acid-modified alkyd resin is prepared from an unsaturated fatty acid, benzoic acid, trimethylolpropane, pentaerythritol, maleic anhydride, isophthalic acid, ethylene glycol monobutyl ether and butanol. The aqueous acrylic acid-modified alkyd resin is prepared by adding styrene, methyl methacrylate, butyl acrylate, acrylic acid, a silane coupling agent, benzoyl peroxide, tert-butyl hydroperoxide, ethylene glycol monobutyl ether and a mixing neutralizer into the basic alkyd resin. According to the aqueous acrylic acid-modified alkyd resin and the preparation method thereof, the advantages of alkyd resin and acrylic resin are integrated, and a product has high gloss retention, color retention and weather resistance; a production process is simple, the raw materials are readily available, and the production cost is low; a paint production process is simple, water is used as a diluting agent, and safety and convenience in construction are ensured.

The invention relates to low melting point copolyester and a preparation method thereof. The low melting point copolyester is made from the following monomers followed by the esterification reaction and the polycondensation reaction: (a) terephthalic acid (PTA) and isophthalic acid (IPA), (b) 1, 4- butanediol (BDO) and (c) polyethylene glycol 600 to 6000 (PEG); wherein, in the a component, the feeding mass ratio of the terephthalic acid and the isophthalic acid is between 80 to 20 : 20 to 80; in the c component, the feeding weight ratio of polyethylene glycol is 1 to 30 percent based on the a; the molar ratio of the a and the b is 1:1.5 to 2.3. The preparation method comprises an esterifcation stage and a polycondensation stage. The copolyester has the characteristics of low melting point, good crystallization property, high intrinsic viscosity and difficult adhesion of particles, and is suitable for spinning the filament, the staple fibers and the non-woven fabrics.

The water soluble copolyester is prepared with polytetrahydrofuran in number average molecular weight of 350-20000 as the fourth component, and metaphthalate-5-sodium sulfonate, metaphthalate dihydroxyethyl-5-sodium sulfonate, metaphthalate dimethyl-5-potassium sulfonate, or other metaphthalate type sulfonate as the third component, and through polycondensation in PTA or DMT path. Compared with the copolyester with polyglycol and other aliphatic flexible compound as the fourth component, the present invention is water soluble and has better crystallizing performance. The product produces no adhesion during drying, and may be blended with conventional polyester slice to obtain POY sea island cotton with flexible elastic process to raise the spinnability and processibility of sea island fiber.

The present invention provides composite material used for preparing fast flowing high-temperature resistant nylon, which comprises the following components: 20 to 84.9 weight portions of high-temperature resistant nylon resin and 0.1 to 10 weight portions of flowing modifier, wherein, the high-temperature resistant nylon resin is selected from the semi-aromatic nylon with the self melting point between 290 DEG C to 330 DEG C; the semi-aromatic nylon is obtained by the copolymerization of terephthalic acid or isophthalic acid, the diamine with 4 to 12 carbon atoms and the aliphatic nylon with 6 to 24 carbon atoms. The fast flowing high-temperature resistant nylon of the present invention has good heat resistance and fluidity and good chemical performance, exact formability and size stability and is mainly used for the production of thin-wall product in the electronic appliance field.

The invention relates to a filament low-melting-point polyester fiber and a preparation method thereof. The filament low-melting-point polyester fiber is in a skin-core structure, a skin layer is made of low-melting-point polyester; a core layer is made of PET (polyethylene terephthalate); the low-melting-point polyester consists of a terephthalic acid chain segment, an isophthalic acid chain segment, an ethylene glycol chain segment, a diethylene glycol chain segment, a molecular weight modifier chain segment and a 1, 12-Dodecanediol chain segment containing branched chains; a molecular weight modifier corresponding to the molecular weight modifier chain segment is specifically a monoacid series or a diacid series; the preparation method of the filament low-melting-point polyester fiber comprises the following steps: polymerization of the low-melting-point polyester and skin-core composite spinning, so as to obtain the filament low-melting-point polyester fiber. The prepared filament low-melting-point polyester fiber has the advantages that the initial melting point is reduced, the melting speed is increased, the polyester fiber is immediately melted at the corresponding temperature, and the melting effect is good.

This invention relates to a biocatalytic process to produce terephthalic acid and isophthalic acid from p-xylene and m-xylene, respectively. Terephthalic acid has been prepared by oxidizing p-xylene with bacteria belonging to the genus Burkholderia. Conversion of p-xylene into terephthalic acid is accomplished by a single bacterial strain that produces all of the requisite enzymes. In addition, this invention relates to the preparation of isophthalic acid from a mixture of m- and p-xylene.