36results about How to "Extend polymerization time" patented technology

The present invention relates to a rubber composition based on a reinforcing filler and on an elastomer matrix comprising a highly saturated diene elastomer comprising at least five distinct units of A, B, C, D and E distributed randomly within the elastomer at respective molar fractions of m %, n %, o %, p % and q %, where m+n+o+p+q=100; m≥50; n+o+p+q≥10; and 15≥p+q≥2.This rubber composition enables a satisfactory degree of stiffness to be reached while maintaining hysteresis properties acceptable for use in the manufacture of tires for running vehicles.

The invention relates to a copolyester of furandicarboxylic acid and a preparation method thereof. The preparation method comprises: the first component, the second component and the The third component is mixed with the esterification catalyst to react to obtain the first intermediate product, wherein the first component includes at least one of furandicarboxylic acid and furandicarboxylic esters, and the second component includes aromatic dihydric alcohols 1. At least one of aliphatic dihydric alcohols, the third component includes polyhydric alcohols with a number of hydroxyl groups greater than or equal to 3; then the first intermediate product is subjected to prepolymerization and polycondensation reactions to obtain furandicarboxylic acid copolyester. In the preparation method, the polyol with the number of hydroxyl groups greater than or equal to 3 is used as the linking point of the chain segment, so that the chain segment structure of the furandicarboxylic acid copolyester is expanded into a network structure, thereby obtaining a colorless or light-colored polyol with excellent mechanical properties and gas Barrier high molecular weight furandicarboxylic acid copolyester.

This invention relates to preparation method of random polyether, primary solve problem of long polymerization time and large catalyzer dosage that exist in ancient technology which takes fatty alcohol or fatty acid as initiator, alkali as catalyzer to prepare random polyether. This invention takes fatty alcohol or fatty acid as initiator, bimetal prussiate as catalyzer to catalyze mixture of oxirane and propylene oxide to gain random polyether, better solve above problem, can be used in industrial production of random polyether.

The invention provides a high-stability high-toughness melamine resin modifier. The melamine resin modifier is prepared from the following components in percentage by mass: 30-50% of fatty acid amide, 20-40% of polyethyleneglycol, 10-20% of alkylphenol polyoxyethylene and 10-30% of water. The melamine resin modifier is prepared by the following steps: putting the components in a proper container, slowly heating to 50-80 DEG C, stirring uniformly until all the components are dissolved, and cooling to room temperature to obtain the melamine resin modifier. The melamine resin modifier can effectively prolong the polymerization time of the melamine formaldehyde resin, increase the storage cycle and improve the toughness of the resin.

The present invention relates to a vinyl chloride-based copolymer which has good processability and thus is capable of providing molded articles having good appearance characteristics, for example, transparency, a method for preparing the same, a thermoplastic resin composition containing the same, and a thermoplastic resin molded article produced from the thermoplastic resin composition. The vinyl chloride-based copolymer includes N-vinyllactam-based polymer compound derived units and unsaturated fatty acid ester derived units at an appropriate ratio, and may have improved structure stability and good processability due to the N-vinyllactam-based polymer compound derived units and improved plasticity and processability due to the internal plasticizer action of the unsaturated fatty acid ester derived units. Therefore, the vinyl chloride-based copolymer according to the present invention may be easily applied in industries that need thereof.

The invention discloses a method of preparing peroxide vulcanized fluororubber through nano emulsion polymerization. The method comprises following steps: step one, compounding a fluorine ether emulsifier and a co-emulsifier according to a mass ratio of (60:40)-(80:20) to obtain a water solution with a nano emulsion polymeric surfactant concentration of 35-65%; step two, under the action of nano emulsion polymeric surfactant and an initiator, carrying out nano emulsion polymerization of one or more fluorine containing monomers or one or more vulcanized point monomers in a polymerization kettle; and step three, subjecting the latex obtained in polymerization to agglomeration, washing, drying, and dehydration, and preparing peroxide vulcanized fluororubber sheets by an open mill.

The invention provides a method for controlling temperature of a butyl rubber reactor. The method includes the steps that signals of a pressure transmitter of an ethylene tank are fed back to adjust a pressure regulating valve of the ethylene tank, the pressure of the ethylene tank is controlled below first pressure, the liquid column pressure difference value between normal ethylene liquid level elevation and heat exchange tube bundle top elevation of the reactor is subtracted from ethylene vapourizing pressure below minus 100 DEG C, and the obtained difference value and an adjusting margin value between the pipeline resistance drop from an outlet of the ethylene tank to an inlet of a heat exchange tube bundle of the reactor and a 10KPa adjustable decompression element are added to obtain the first pressure value; pressure drop of the adjustable decompression element is adjusted, so that the pressure of ethylene entering the heat exchange tube bundle of the reactor is equal to the ethylene vaporizing pressure below minus 100 DEG C. The method ensures that reactions are conducted stably below minus 100 DEG C, prolongs polymerization time, reduces the probability of reaction unexpected interrupt, improves productivity and production efficiency and reduces instability of the polymerization process. The method is simple in technological flow path and easy to operate, high in control accuracy, low in operation cost and safe and reliable in production, installation is convenient, and energy does not need to be consumed in the process.

A functional mutant of human plasminogen disclosed in the invention, respectively, is hPLG-delta K: human plasminogen protein Pro<544>-Asn<791> polypeptide; Pro<559> in RGD-hPLG-delta K: hPLG-delta K is mutated to Asp<559>; and Gly<560> in RHP-hPLG-delta K: hPLG-delta K polypeptide is mutated to His<560>. The invention also discloses a preparation method for the functional mutant. The product is obtained by using a plasmid containing a full-length cDNA sequence of human plasminogen as a template to carry out a PCR to construct a plasmid and using Pichia Pastoris expression. The functional mutant has a dual-function of fibrinolysis and inhibiting platelet aggregation or inhibiting fibrin monomer polymerization.