263 results about "Intrinsic viscosity" patented technology

The invention relates to the technical field of chemical fibers, in particular to a low-melting-point polyester FDY (fully drawn yarn) preparation process which comprises the following steps: preparing raw materials, selecting polyester chips and a low-molecular-weight polyester copolymer, mixing the polyester chips and the low-molecular-weight polyester copolymer according to a ratio, melting and blending the polyester chips and the low-molecular-weight polyester copolymer with the additive amount of 5-8wt% and the intrinsic viscosity of 0.65-0.70 dL / g, and performing extrusion molding to obtain the low-melting-point polyester FDY. And putting the mixed raw materials into a screw extruder, and carrying out melt blending and spinning treatment at 250-260 DEG C. According to the low-melting-point polyester FDY and the preparation method thereof disclosed by the invention, a component regulation end is arranged, so that a synergistic effect mechanism of a polyester matrix and a low-melting-point copolymer is accurately matched in a preparation process of the low-melting-point polyester FDY, and the uniformity of melt components is ensured; meanwhile, the copolymerization structure design directivity acts on molecular chain regularity regulation and control, thermal stability fluctuation in the spinning process is inhibited in real time, it is guaranteed that the continuous forming capacity of fibers is maintained under the high-speed spinning condition, and the stability of a production line is improved.

The invention relates to the technical field of high polymer material processing and process detection, and discloses an ultrasonic transmission-based regenerated polyester homogenization kettle on-line viscosity monitoring method, which comprises the following steps of: constructing a multi-channel ultrasonic transmission sensing array in a homogenization kettle to obtain melt acoustic propagation characteristics in real time; the intrinsic viscosity is dynamically analyzed based on a sound velocity-attenuation joint inversion model; viscosity data and stirring, heating and other execution units are subjected to closed-loop linkage, and technological parameters are regulated and controlled in a graded mode according to the deviation and the duration. According to the method, non-contact, real-time and accurate monitoring and active regulation and control of the viscosity of the regenerated polyester melt are realized, and the batch consistency of products and the intelligent level of production are remarkably improved.

The preparation method comprises the following steps: sequentially carrying out esterification reaction and polycondensation reaction on terephthalic acid, ethylene glycol, equol or a derivative thereof in the presence of the catalyst to generate the modified polyester, wherein the catalyst is prepared by enabling antimony trioxide, stannous octoate, tetrabutyl titanate and triphenyl phosphite to react in a solvent at the temperature of 100 DEG C or above; the modified polyester prepared by the method has relatively high intrinsic viscosity and fracture tensile strength, can meet the application requirements of special high polymer materials, and solves the problem that the application of semi-biomass PET copolyester in the field of special high polymer materials is limited in the prior art.

The invention relates to the technical field of polyester yarns, in particular to a high-strength polyester yarn and a preparation method thereof.The method comprises the steps that PET slices with the intrinsic viscosity of 0.85-1.00 dL / g are subjected to melt spinning and cooled through circular blowing to obtain nascent fibers, the nascent fibers are subjected to surface activating treatment through low-temperature plasma or esterase bio-enzyme, and the high-strength polyester yarn is obtained; the preparation method comprises the following steps: firstly, activating fibers, then carrying out graft copolymerization reaction on the activated fibers and graft monomer solutions such as fluorinated acrylate and acrylic acid, and finally, cleaning, drying, carrying out thermal network and winding on the composite fibers, so that the prepared polyester yarn has the breaking strength of more than or equal to 7.7 g / D, the dry heat shrinkage rate of less than or equal to 3.5% and the shrinkage tension of less than or equal to 0.03 g / D, has the high functional characteristics of lasting super-hydrophobicity, antibacterial property and the like, is excellent in washing resistance, and is suitable for industrial production. The problem that functionalization is difficult due to surface inertia of the polyester fiber is solved, and the mechanical property and the surface characteristic of the polyester fiber are comprehensively improved.

This invention discloses a method for preparing poly(glycolic acid-caprolactone) copolymers, belonging to the field of polymer synthesis technology. The method includes: prepolymerizing ε-caprolactone with a catalyst and initiator at 40–60°C below the melting point of glycolide under an inert atmosphere; adding glycolide and heating to 160–220°C for the main polymerization reaction; after the reaction, dissolving, precipitating, washing, and drying to obtain the poly(glycolic acid-caprolactone) copolymer. This invention utilizes the physical difference in melting points between glycolide and ε-caprolactone, preferentially prepolymerizing ε-caprolactone at a temperature below the melting point of glycolide, resulting in a higher conversion rate of ε-caprolactone than glycolide in the initial stage of the main polymerization, effectively controlling the copolymerization reaction pathway. Using this method, copolymers with a weight-average molecular weight of not less than 100,000 Da and an intrinsic viscosity of 1.8–3.5 dL / g can be obtained within a wide range of glycolide molar content from 15% to 85%, and the degradation behavior is stable and controllable. This method is simple and requires no special equipment or chain extender, making it suitable for the large-scale preparation of medical materials such as absorbable sutures and tissue repair scaffolds.

Provided is a polyethylene powder that completes swelling in a short time, offers a uniform appearance or shape of a molded article, and produces a molded article with smooth surface even by high-speed molding.The polyethylene powder satisfies (requirements 1 and 2). (Requirement 1): an intrinsic viscosity (IV) is 1.5 dL / g or more and 34.0 dL / g or less, and (requirement 2): a ratio γ0 / γ1 of an elastic limit strain γ0 at a swelling time t (h) of 0 hours to an elastic limit strain γ1 at a swelling time t (h) of 1 hour is 0.80 or more and 0.95 or less, wherein the ratio is obtained from a strain dependence test.

The present application relates to the technical field of detection, and particularly relates to a method for measuring intrinsic viscosity of rubber by using chlorobenzene solution, comprising the following steps: obtaining initial mass of insoluble polymer sample; filtering solution of the sample to obtain mass of insoluble substance intercepted by filter medium; cleaning container of the sample of the solution and collecting cleaning liquid to obtain mass of container residue; determining real sol mass based on the mass of the residue, the mass of the insoluble substance and the mass of the container residue; and determining concentration of the solution based on the real sol mass and volume of the solution. The present application effectively solves the technical problem of large error in measuring intrinsic viscosity by using tetrahydrofuran solvent, and simultaneously provides an alternative scheme for evaluating quality of natural rubber.

The present invention addresses the problem of providing a polyester film which has excellent material recyclability. A polyester film according to the present invention comprises: a base material film that contains a polyester resin; and a functional layer that is provided on at least one surface of the base material film. The self-hydrolysis resistance parameter SHS represented by formula 1 satisfies 1.50 or less.　Formula 1: SHS = 0.245([IV]f -1.47 - [IV]i -1.47) (In the formula, [IV]i represents the limiting viscosity IV of the polyester film. [IV]f represents the limiting viscosity IV after heat-treating the polyester film at 300°C for 2 hours in a nitrogen atmosphere.)

Process and apparatus for processing of polycondensates, in particular for recycling processing of contaminated polycondensates, comprising the following processing steps: a) initially charging the polycondensates / materials to be processed, in particular in a container, b) at least partially, especially completely, melting the polycondensates, in particular by extruding in an extruder, and preparing a polymer melt, c) mixing the polymer melt, d) cooling the polymer melt, e) treating the mixed and cooled polymer melt in a melt reactor, in particular for polycondensation / postcondensation, to increase the intrinsic viscosity and / or to purify the polymer melt.

A method for preventing adhesion of and clogging with a mineral raw material by performing at least any of transfer and treatment of a raw material mixture in which a mineral raw material has been brought into contact with a cationic w / o emulsion polymer in a transfer and treatment facility and preventing adhesion of and clogging with the mineral raw material in the transfer and treatment facility, wherein the cationic w / o emulsion polymer has an intrinsic viscosity of 10.0 dL / g or less.

The invention belongs to the technical field of spinning, and relates to a method for reducing PET melt spinning pressure on the premise of low damage to fiber performance. The silicone with specific content, specific structure and specific molecular weight is introduced into the PET melt in the form of master batch, so that the pressure of a spinning component can be remarkably reduced, and the intrinsic viscosity of the PET body and the mechanical property of the fiber can be maintained as much as possible on the premise of not changing the main chain structure of the PET, not changing the molecular weight of the PET body and not depending on the dispersion of nano particles.

A polyester composition and a product thereof are provided. The polyester composition includes a resin (A), a fiber reinforcement (B), an organic reinforcement (C), a crystal nucleating agent (D), and a toughening agent (E). An intrinsic viscosity of the resin (A) is 0.6 dL / g to 0.85 dL / g.

The invention belongs to the technical field of high polymer material synthesis, and relates to application of 1-butyl-2, 3-dimethylimidazole trifluoromethanesulfonate as a cocatalyst in direct esterification synthesis of PET (Polyethylene Terephthalate), which comprises the following steps: adding purified terephthalic acid, ethylene glycol, 1-butyl-2, 3-dimethylimidazole trifluoromethanesulfonate and a polycondensation catalyst into a reaction kettle; the method comprises the following steps: replacing air in a reaction kettle with inert gas, controlling the pressure in the reaction kettle to be 0.20-0.24 MPa, heating to 222-227 DEG C, stirring to carry out esterification reaction for 80-110 minutes, releasing the pressure to normal pressure, heating to 260-280 DEG C, and carrying out polycondensation reaction under a negative pressure condition to obtain a PET product after the polycondensation reaction is finished, and the PET product has the intrinsic viscosity of 0.70-0.75 dL / g, the terminal carboxyl group content of less than or equal to 50 mmol / kg, the L value of more than or equal to 60 and the b value of less than or equal to 4.5. The method provided by the invention solves the problem of high energy consumption in traditional PET synthesis, improves the esterification reaction rate, inhibits side reactions, reduces the production cost, and improves the quality of PET products.

The present invention relates to a process for recycling a stream of polyester waste material by depolymerizing polyesters by alcoholysis to a liquid mixture comprising oligomeric esters having 5 to 20 subunits, and continuously feeding said liquid mixture of oligomeric esters to a reactor in which said liquid mixture is present in combination with a gas headspace, said reactor having means for increasing the interface between said liquid mixture and said gas headspace by at least 5 times relative to a horizontal cross section of said reactor, and maintaining a pressure in said headspace of less than 20 mbar, whereby said oligomeric esters are repolymerized to polyesters having an intrinsic viscosity of at least 0.3 dL / g during a residence time of the mixture in said reactor of less than 120 minutes. The present invention also relates to a system for applying this process.

A gas separation membrane, a preparation method therefor, and the use thereof in which the gas separation membrane comprises 60-100 mol % of a monomeric unit derived from α,β,β-trifluorostyrene, and has an intrinsic viscosity of 0.5-5.0 dL / g and a tensile strength of at least 50 MPa. According to the GB / T 1038-2000 test method test, the permeability coefficient of hydrogen is at least 100 barrer.

The present invention relates to a polyolefin composition, to an article comprising said polyolefin composition, preferably to a cable comprising an insulating layer comprising said polyolefin composition, and to the use of said polyolefin composition as cable insulation for medium and high voltage cables, the polyolefin composition having a total ethylene content of from 20.0 to 32.5 wt% based on the total weight of the polyolefin composition and determined by Crystallization Extraction (CRYSTEX) by FT-IR spectroscopy calibrated by Quantitative 13C-NMR spectroscopy; a melt flow rate MFR2, determined according to ISO 1133 at 230 DEG C and 2.16 kg, of greater than 2.5 to 6.0 g / 10 min; a crystalline fraction (CF) content determined by crystallization extraction (CRYSTEX) in an amount, based on the total weight of the polyolefin composition, in the range of 75.0 to 95.0 wt%, said crystalline fraction (CF) having an ethylene content (C2 (CF)) determined by FT-IR spectroscopy calibrated by quantitative 13C-NMR spectroscopy in the range of 18.0 to 32.5 wt%, based on the total amount of monomer units in the crystalline fraction (CF), and a soluble fraction (SF) content, determined by crystallization extraction (CRYSTEX), in an amount, based on the total weight of the polyolefin composition, in the range of 5.0 to 25.0 wt%, said soluble fraction (SF) having an intrinsic viscosity (iV (SF)), determined according to ISO 1628-3, in the range of 90 to 200 cm3 / g.

The present disclosure describes a computer-implemented method, system, and computer program product for determining the intrinsic viscosity and Huggins constant of an unknown sample. In one embodiment, the method, system, and computer program product includes receiving specific viscosity values ​​over time from a viscometer corresponding to a series of aliquots of an unknown sample injected into an instrument chain, the instrument chain including the viscometer, calculating a total mass of each of the aliquots, calculating a first intermediate viscosity value for each of the aliquots, calculating a second intermediate viscosity value for each of the aliquots, and fitting the total mass, the first intermediate viscosity value, and the second intermediate viscosity value to a fitting to yield a calculated intrinsic viscosity of the unknown sample and a calculated Huggins constant of the unknown sample.

The invention discloses an optimization process for preparing hydrolysis-resistant PET (polyethylene terephthalate) master batch. The optimization process comprises the following steps: S1, pretreating raw materials; s2, low-temperature pre-dispersion: adding the dried raw materials weighed according to the formula proportion into a high-speed mixer, so that the anti-hydrolysis agent and the auxiliary agent are uniformly attached to the surface of the PET base material to form a premix; s3, mild extrusion granulation: melting and mixing the premix through a twin-screw extruder, and extruding the premix into filaments through a die head; s4, the filaments are rapidly cooled and shaped through a cooling water tank, and secondary cross-linking is avoided; s5, pelletizing by adopting a pelletizer to obtain primary master batches; s6, the primary master batch is subjected to vacuum drying, surface moisture is removed, and the anti-hydrolysis PET master batch is obtained.The thermal degradation of a PET base material and the advanced reaction of an anti-hydrolysis agent are reduced, the intrinsic viscosity of the master batch is stable, and the anti-hydrolysis efficiency is improved.

The present invention aims to solve the above problems and provide a monofilament that has low intrinsic viscosity while possessing high hydrolysis resistance, which was not possible with conventional technology. [Solution] A polyester monofilament comprising a resin composition mainly composed of polyester resin, wherein the resin composition contains 0.01 to 4.00 parts by mass of an amine compound and 0.01 to 4.00 parts by mass of an isocyanate compound per 100 parts by mass of polyester resin.

A polypropylene based composition comprising: A) from 40 wt% to 85 wt% of a first heterophasic propylene ethylene copolymer (HECO1) B) from 15 wt% to 60 wt%; of a second heterophasic propylene ethylene copolymer (HECO2) having: i) fraction soluble in xylene at 25°C ranging from 20.0 wt% to 38.0 wt%; ii) the melt flow rate (230°C / 5 kg.. ISO 1133) ranging from 0.2 g / 10min to 4.0 g / 10min; iii) intrinsic viscosity, measured in tetralin, of the fraction soluble in xylene at 25°C ranging from 5.7 dl / g to 9.2 dl / g.

The invention belongs to the technical field of high polymer materials, and particularly relates to a polystyrene composite material as well as a preparation method and application thereof. Specifically, the invention discloses a polystyrene composite material which comprises the following components in parts by weight: 50-85 parts of HIPS (High Impact Polystyrene) resin; 10 to 35 parts of PPE resin; 2 to 15 parts of a phosphazene compound; 1-5 parts of a toughening agent; wherein the intrinsic viscosity of the PPE resin is 33 to 48 cm < 3 > / g; the mass fraction of polybutadiene in the HIPS resin is 3-8%; the phosphazene compound has a specific structure. The invention provides a halogen-free flame-retardant polystyrene composite material with good heat resistance and fluidity, which can be used for preparing electrical components.

The invention discloses a regenerated PET (Polyethylene Terephthalate) material as well as a preparation method and application thereof. The preparation method of the regenerated PET material comprises the following steps that regenerated PET slices are subjected to stage heating pre-crystallization treatment, a compound main catalyst is combined for reactive extrusion, then solid-phase tackifying is conducted, and the prepared regenerated PET material has high intrinsic viscosity, low yellowness and high tensile strength; the intrinsic viscosity of the prepared regenerated PET material is not lower than 0.66 dL / g, the yellowness change value is not higher than 3.5, and the tensile strength is not lower than 50 MPa.

The present invention provides a masterbatch that, when diluted with a polyester resin, yields a resin composition with good processability and moldability, as well as good transparency and low yellowness. [Solution] A masterbatch containing amorphous PET (A) and a chain extender (B) having a weight-average epoxy functional group count of 3 to 65 and a weight-average molecular weight of 2000 to 30000. The content of the chain extender (B) in the masterbatch is 5 to 30% by mass. Furthermore, the intrinsic viscosity after melt-kneading alone is IV. a The intrinsic viscosity of a resin composition sample obtained by melt-kneading crystalline PET with a viscosity of 0.9-1.0 dL / g and a masterbatch in a proportion that results in a chain extension agent (B) content of 0.4% by mass is IV. b When set to (dL / g), 0 <IV b -IV a The value is <0.29. Furthermore, this masterbatch is used by mixing it with a polyester resin under conditions that the content of the chain extender (B) in the resin composition is 0.01 to 1.0% by mass.

The invention belongs to the technical field of high polymer material synthesis, and relates to application of magnesium ethoxide as a catalyst in direct esterification synthesis of PET (polyethylene terephthalate), purified terephthalic acid, ethylene glycol and catalyst slurry are added into a reaction kettle, and the catalyst slurry is magnesium ethoxide-ethylene glycol mixed liquid; the method comprises the following steps: replacing air in a reaction kettle with inert gas, controlling the pressure in the reaction kettle to be 0.20-0.24 MPa, heating to 222-227 DEG C, stirring to carry out esterification reaction for 110 minutes or more, releasing the pressure to normal pressure, heating to 260-280 DEG C, and carrying out polycondensation reaction under a negative pressure condition to obtain a PET product after the polycondensation reaction is finished, and the PET product has the intrinsic viscosity of 0.70-0.75 dL / g, the terminal carboxyl group content of less than or equal to 40 mmol / kg, the L value of more than or equal to 60 and the b value of less than or equal to 5.5. According to the method, magnesium ethoxide is used for replacing an antimony catalyst, so that the problems of high toxicity and high process energy consumption of the antimony catalyst in the traditional PET direct esterification method are solved, the side reaction is inhibited, the production cost and the environmental protection risk are reduced, and the method is suitable for continuous PET industrial production.

An impact copolymer blend comprising: an impact copolymer comprising a polypropylene matrix, from about 75 wt. % to about 95 wt. %, based on the weight of the impact copolymer; ethylene-propylene rubber (EPR) phases, from about 25 wt. % to about 5 wt. %, based on the weight of the impact copolymer; wherein the EPR phases are dispersed within the polypropylene matrix; wherein the EPR phases comprise about 20 wt. % to about 50 wt. % of ethylene, based on the weight of the EPR phases; wherein the ratio of the intrinsic viscosity of the EPR phases and the intrinsic viscosity of the polypropylene matrix is from about 0.7 to about 1.3; and additives comprising a primary antioxidant; a secondary antioxidant; and an acid scavenger. The impact copolymer blend may be cast into films and heat-resistant flexible packaging.

A hot melt adhesive composition comprises a plasticizer having at least one ester bond and a (co) polyester resin component, and is preferably compostable, the (co) polyester resin component: (1) having substantially amorphous domains and crystalline domains, or (2) a blend comprising at least one substantially amorphous (co) polyester resin and at least one semi-crystalline or crystalline (co) polyester resin. The composition has a Tg of less than about 10 DEG C, a DSC melt temperature of between about 20 DEG C and about 80 DEG C, an intrinsic viscosity of between about 0.3 dl / g and about 0.8 dl / g, and a melt viscosity at 300 DEG F of between about 2,000 and about 50,000 cP. The composition can be applied at application temperatures typical in the hygienic field, including by spraying, and is suitable for use as a structural adhesive for non-woven substrates for disposable hygienic products, such as baby diapers or adult incontinence products.

A polyolefin composition comprising: A) from 85 wt% to 99.0 wt%;of a propylene homopolymer B) from 1.0 wt% to 15.0 wt%; of a propylene, ethylene copolymer composition having: iii) intrinsic viscosity, measured in tetralin, of the fraction soluble in xylene at 25°C ranging from 5.7 dl / g to 9.2 dl / g; propylene, ethylene copolymer composition component B) comprises: b1) from 27 wt% to 40 wt%; of a propylene homopolymer having a melt flow rate MFR1 (230°C / 2.16 kg. ISO 1133) ranging from 62.0 g / 10min to 100.0 g / 10min; b2) from 27 wt% to 40 wt% of a propylene homopolymer having a melt flow rate MFR2 (230°C / 2.16 kg. ISO 1133) lower than MFR1; b3) from 20 wt% to 46 wt% of a propylene ethylene copolymer having a content of ethylene derived units ranging from 18.0 wt% to 48.0 wt%.

The invention relates to a sulfur-containing piperidine copolymer as well as a preparation method and application thereof. The structure of the sulfur-containing piperidine copolymer is shown as a formula (I), wherein 0 < x < 1; n > = 1, and n is an integer; ar is a structure containing an aromatic ring; r1 is as shown in the specification; the intrinsic viscosity of the sulfur-containing piperidine copolymer is 1 to 4 dL / g. According to the invention, a specific sulfur-containing structure and an ether-containing chain segment are respectively introduced into the main chain and the side chain of the sulfur-containing piperidine copolymer, so that the sulfur-containing piperidine copolymer not only can form a film well after being mixed with lithium salt, but also can enable a solid electrolyte film prepared from the sulfur-containing piperidine copolymer to have excellent ionic conductivity and cycle retention rate under the conditions of room temperature and high temperature. In addition, the solid electrolyte membrane prepared from the sulfur-containing piperidine copolymer has low electrochemical impedance, wide chemical oxidation window, excellent lithium ion transference number, coulombic efficiency and specific capacity.

The application discloses a kind of polyether ketone ketone and preparation method thereof, the application is first added terephthaloyl chloride or isophthaloyl chloride and diphenyl ether, then under the condition of adding catalyst anhydrous aluminium chloride, low-temperature prepolymerization for a certain time, then the remaining diphenyl ether is added to complete the short-chain end-capping reaction.The application reduces the temperature in the early stage of the starting reaction process and adopts the reflux method in the selection of the washing reagent in the later stage, so that the purity and molecular weight of the obtained high molecular polymer polyether ketone ketone are high.The content of aluminum, a catalyst contained in PEKK, is lower, and the intrinsic viscosity (molecular weight) and tensile strength of the tested product are higher.

The application discloses a kind of high-dispersed zinc oxide nanocomposite polyester chips and preparation method thereof.The application is aimed at improving the dispersing ability and compatibility of ZnO nanoparticles in polyester matrix by suitable and effective surface modification, achieving good dispersion of antibacterial components in polyester matrix during in-situ coating process, and maintaining good spinning and antibacterial performance.ZnO nanoparticles after surface modification are dispersed again in D 90 The modified polyester chips have a size of 100-500 nm and an intrinsic viscosity of about 0.6-1.5 dL / g.The ZnO nanocomposite polyester chips can be used for the preparation of polyester fibers, which have improved antibacterial performance while maintaining good mechanical properties and color phase, ultimately improving product quality and reducing cost.In addition, the prepared polyester fibers have excellent antibacterial effect on escherichia coli and staphylococcus aureus.