38results about How to "Short polycondensation time" patented technology

The invention discloses a biodegradable linear random copolyester, its preparation method and uses, wherein the copolyester has a structural unit of (1), wherein m is an integer of 2-10, n is an integer of 0-8, p is an integer of 2-10, m, n, p are identical or different, x is an integer of 1-10, y is an integer of 1-10, the average molecular weight Mw of the copolyester is 100,000-600,000g / mol, its molecular weight distribution is 1.2-3, which is measured through GPC method. The copolyester can be widely applied into section bar, film, fabric and coating.

This invention publishes a biodegradable polyester catalyst system and its application. Such a catalyst system as a binary system consists of rare earth compound C1 and one of the compounds of titanium, stibium and zincum C2, with a C1 / C2 mole ratio of 5:95~100:0. The catalyst is specifically applicable in preparing polyesters with an aliphatic groups / aromatic groups mole ratio of 35 / 65~100 / 0 and a weight-average molecular weight of 3000~200000g / mol (identified by GPC). The catalyst system in this invention significantly promotes the condensation polymerization rate and product molecular weight and improves the problem of yellow-color products from single-component titanium catalyst system.

The invention discloses a phosphorus-containing flame-retardant polyester and its preparation method and application. The flame-retardant polyester is mainly prepared by mixing terephthalic acid and ethylene glycol, and adding auxiliary agents and flame retardants for polymerization; The flame retardant is a flame retardant compounded by alkyl substituted diethylene glycol phosphate and 2-(tert-butanol cyclotriphosphazene) 1,3-benzenediol diglycidyl ether (BCP). The flame retardant polyester prepared by the present invention has short polycondensation time, good product hue, and good flame retardant performance. The L value of the prepared polyester reaches 85, the b value is within 3, and the flame retardant performance of the sample is LOI ≥ 29%; the obtained polyester Widely used in the field of fiber and film, the polyester can be added as a masterbatch or directly used to prepare fibers and films. Fibers prepared from the polyester are used in industrial textiles, architectural interior decoration materials, vehicle interior decoration materials, protective clothing, carpets, etc.; compared with conventional similar polyester films, the films prepared from the polyester have lower Haze and good flame retardant properties.

The invention discloses a fatty polyester compound and a preparation method thereof, including the following steps: (1) synthesis of condensation fatty co-polyester: the react between two, three or four fatty dicarboxylic acids or the esters thereof and fatty dibastic alcohol is conducted to achieve condensation fatty co-polyester; (2) the condensation fatty co-polyester reacts with poly lactic acid under the existence of double functional-group chain-extension agent and the extruded out, the achieved fatty polyester compound is the blend of high molecular weight fatty co-polymer, high molecular weight fatty block copolymer and high molecular weight poly lactic acid. The weight percents of condensation fatty co-polyester and poly lactic acid drop is 5:95-95:5. The preparation method has the advantages that the condensation duration is short, the process control is stable and simple, and the method can be directly applied to various processing techniques such as film inflation, extrusion, vacuum molding, blow molding, foaming, and the like; the achieved products have high purity and nice color; the performance adjustment is flexible and convenient, and the cost is low.

The invention discloses a method for preparing a biodegradable aliphatic-aromatic copolyester. The steps include: adding epoxy soybean oil after continuous esterification of aromatic dicarboxylic acid and aliphatic dicarboxylic acid, and continuously Pre-condensation, in the pre-condensation process, the epoxy group is inserted into the polybutylene terephthalate-adipate-PBAT molecular chain through transesterification, and then the polycondensation is carried out continuously at a higher temperature, so that the molecular weight , The intrinsic viscosity reaches the target value. The preparation method of the biodegradable aliphatic-aromatic copolyester disclosed by the present invention can make it easier for the polyester to reach the target intrinsic viscosity and molecular weight, reduce the polycondensation time of high-temperature and high-viscosity materials, reduce side reactions, and reduce product ends. Carboxyl value, solve the problem of resin yellowing. The preparation method of the biodegradable aliphatic-aromatic copolyester disclosed by the invention does not use a small molecule chain extender to extend the chain, and solves the problem of the migration of the residual chain extender from plastic to food.

The present invention discloses a foamable PET resin, a preparation method and uses thereof. The preparation method comprises: (1) uniformly mixing raw material components, wherein the raw material components comprise 985-995 parts of physically recycled PET bottle flakes, 1-9 parts of a chain extender, 1-3 parts of an antioxidant, and 1-3 parts of a thermal stabilizer, and a three-functional-group chain extension monomer and a multi-functional-group chain extension monomer having a functional group number of 4-6 are compounded according to a mass ratio of 1:3-5:1 to prepare the chain extender; (2) carrying out melt extrusion granulation; and (3) carrying out solid phase condensation polymerization on the obtained material for 1-5 h at a temperature of 210-230 DEG C under a vacuum degree of 5-100 Pa so as to obtain the foamable PET resin. According to the present invention, the foamed PET resin has characteristics of high molecular weight, wide molecular weight distribution, high melt strength, physically recycled PET degrading use changing, low raw material cost, and simple preparation process; and with the combination of the chain extender, the reaction extrusion and the solid phase condensation polymerization are combined, such that the reaction period is shortened, and the industrial production is easily achieved.

This invention publishes a synthesis method for polyesters from rare earth catalysts. In this method, single-kettle operation is adopted. One of the compounds of titanium, stibium and zincum is chosen as the catalyst C1 for transesterification and esterification and is added into the reaction kettle with monomer raw materials before reaction. After a certain period of prepolymerization, a rare earth metal compound as catalyst C2 is added for vacuum condensation polymerization. It is due to the single-kettle operation that this invention has the advantages of simplified technique, accelerated polymerization reaction, promoted product molecular weight, reduced side reactions and significantly improved color of polyester product.

The invention provides a method for preparing polycarbonate by catalyzing a dual-nuclear ionic liquid. Dihydroxy compound and carbonic acid diester are used as raw materials, and are added to a reactor according to a molar ratio of 1:0.9 to 1:8, and are protected by an inert gas. , polycarbonate was synthesized by melt transesterification using binuclear imidazolium-based ionic liquids as catalysts. Compared with the literature reports, by adjusting the length of the alkyl chain between the bis-imidazole rings and changing the structure of the anion, the weight-average molecular weight of the synthesized polycarbonate reached 5×10 4 ~16×10 4 g / mol, the transesterification time is shortened by 25% to 50%, and the polycondensation time is shortened by 20% to 40%.

The invention relates to a preparation method and application of a green titanium-based polyester catalyst, which is characterized in that it comprises the following steps: dissolving ethyl orthosilicate in absolute ethanol, adding an appropriate amount of acidified attapulgite, stirring evenly, and continuing to drip Add a mixed solution of titanium tetraisopropoxide and absolute ethanol, add dropwise a mixed solution of deionized water and absolute ethanol, heat in a water bath, hydrolyze for several hours, stop heating and stirring, wash with absolute ethanol, dry and grind to obtain It is a new type of green titanium-based catalyst. The advantage of the present invention is that the titanium oxide / silicon oxide / attapulgite composite titanium-based catalyst is prepared by the mixed hydrolysis method, and silicon oxide is used to suppress the crystallization of titanium oxide, and at the same time, the attapulgite is used as a carrier to improve the dispersion of titanium oxide and silicon oxide properties, making the activity of the catalyst more stable, thereby reducing the side reactions of the polyester and improving the hue of the polyester produced.