158 results about "Characteristic viscosity" patented technology

An optical article made of a transparent polymer which includes terephthaloyl moieties, optionally, other aromatic diacid moieties; ethylene glycol moieties; isosorbide moieties; and, optionally, one or more other diol moieties, wherein the polymer has an inherent viscosity of at least about 0.35 dL/g as measured on a 1% solution (weight/volume) in o-chlorophenol at 25 DEG C.

A fluid loss additive for hydraulic cement, comprising a polyvinyl alcohol resin and a fluid loss ameliorating sulfonic acid-functionalized co-resin, where the polyvinyl alcohol has a characteristic viscosity in the range of about 1 to about 25 cps. The invention includes, in some embodiments, an aqueous concentrate of the PVOH resin and the sulfonic acid-functionalized co-resin, where the total resin content is in the range of about 10% to about 40% and the viscosity is less than 15,000 cps. By way of the invention it is possible to adjust hydraulic cement slurry characteristics in real time upon demand and reduce inventory by providing a concentrated aqueous fluid loss additive.

A composition including polyalphaolefins that function as drag reducing agents and a process for the preparation of polyalphaolefins that function as drag reducing agents are disclosed. The process includes contacting alpha olefin monomers with a catalyst system, which includes a catalyst and an activator (co-catalyst) in a reactant mixture. The catalyst is a transition metal catalyst, preferably titanium trichloride, and the co-catalyst may include an alkylaluminoxane, alone or in combination, with a dialkylaluminum halide or a halohydrocarbon. The polymerization of the alpha olefin monomers produces a non-crystalline, ultra-high molecular weight polyalphaolefin having an inherent viscosity of at least 10 dL/g. The addition of the alkylaluminoxane during the polymerization process provides for a non-crystalline, ultra-high molecular weight polyalphaolefin and a more uniform molecular weight distribution of the resulting polyalphaolefin, thereby creating a drag reducing agent superior to known drag reducing agents. A process for forming a drag reducing agent comprising a non-crystalline, ultra-high molecular weight polyalphaolefin having an inherent viscosity of about at least 10 dL/g and a process for reducing drag in a conduit are also disclosed.

The invention provides a propylene random block copolymer (A) that has a melt flow rate from 0.1 to 100 g/10 min and a melting point from 100 to 155° C. and includes 90 to 60% by weight of a portion insoluble (D_insol) in n-decane at room temperature and 10 to 40% by weight of a portion soluble (D_sol) in n-decane at room temperature, wherein the D_insol satisfies the following requirements (1) through (3) and the D_sol satisfies the following requirements (4) through (6). The invention further provides molded articles such as sheets, films, injection molded articles, hollow molded articles, injection blow molded articles and fibers, which are formed of the propylene random block copolymer (A) or a propylene resin composition containing the propylene random block copolymer (A). (1) The molecular weight distribution (Mw/Mn) obtained by GPC of the D_insol is from 1.0 to 3.5, (2) the content of skeletons derived from ethylene in the D_insol is from 0.5 to 13% by mole, (3) the total amount of 2,1- and 1,3-propylene units in the D_insol is 0.2% by mole or less, (4) the molecular weight distribution (Mw/Mn) obtained by GPC of the D_sol is from 1.0 to 3.5, (5) the intrinsic viscosity [η] in decalin at 135° C. of the D_sol is from 1.5 to 4 dl/g and (6) the content of skeletons derived from ethylene in the D_sol is from 15 to 35% by mole.

The present invention provides a preparation method of high-temperature nylon, including the following steps: (a) dicarboxylic acid and diamine are used to prepare 6T salt or 6I salt under the temperature of 80 to 110 DEG C and the carbon atomicity n of the obtained paraphthaloyl acidhexamethylene diamine salt or m-phthalic acryl acidhexamethylene diamine salt is 4 to 16; (b) 6T salt or 6I salt obtained in step (a) and 66 salt or hexanolactam are polymerized to obtain primary condensation compound and the characteristic viscosity of the primary condensation compound in dense sulfuric acid is 0.09 to 0.25dl/g under the temperature of 30 DEG C; (c) the primary condensation compound obtained in step (b) is under solid phase condensation and polymerization to obtain the high-temperature nylon under the temperature of not more than 250 DEG C. The method provided by the present invention can increase the polyamide size stability, mechanic performance and heat resistance, reduce the molecular weight distribution of the high-temperature nylon, and prevent the occurrence of amine exchange, thermal degradation, gelation and other side reactions.

A p-aramid fibre pulp is prepared through dissolving the resin "1414" of aramid fibre with a certain characteristic viscosity in concentrated sulfuric acid and high-speed stirring to deposit it. Differential p-aramid fibre pulp can be obtained according to differential use.

The invention provides poly(ethylene 2,5-furandicarboxylate), which contains the repeating units shown in formula (I) and has a characteristic viscosity not smaller than 0.2 dL/g. The invention also provides a preparation method for poly(ethylene 2,5-furandicarboxylate) provided by the technical scheme, which comprises the following steps of: carrying out esterification reaction on 2,5-furandicarboxylic acid and ethylene glycol under the action of a tin catalyst to obtain a first intermediate product, wherein the esterification reaction pressure is 0.1-0.4 MPa; and carrying out condensation polymerization reaction on the first intermediate product under the pressure of 10-70 Pa to obtain poly(ethylene 2,5-furandicarboxylate). Experiments show that poly(ethylene 2,5-furandicarboxylate) provided by the invention is dark brown, and has a characteristic viscosity of not smaller than 0.2 dL/g, a glass transition temperature of 60-63 DEG C and a melting point of 210-215 DEG C.

The invention belongs to the technical field of macromolecular materials, and in particular relates to a preparation method for biodegradable blocked copolyester. The preparation method comprises the following steps: carrying out esterification reaction between adipate and 1,4 butanediol in the presence of catalyst, wherein the reaction time is 3 to 5h, nitrogen is adopted for protection, the reaction pressure is between 0.1 and 0.8MPa and the reaction temperature is between 130 and 180 DEG C during a first stage; and the reaction time is 1.5 to 5h, the reaction pressure is between 0.3 and 0.6MPa and the reaction temperature is between 150 and 200 DEG C during a second stage so as to generate polybutylene adipate; and carrying out ester exchange reaction of dimethyl terephthalate (DMT) and 1,4 butanediol in the presence of catalyst, wherein the nitrogen is adopted for protection, the reaction time is 2 to 5h, the reaction pressure is between 0.1 and 0.7MPa and the reaction temperature is between 150 and 170 DEG C so as to generate polybutylene terephthalate (pbt); and mixing both prepolymers and carrying out melt copolycondensation reaction under negative pressure, wherein the vacuum degree is controlled to be between 0 and 200Pa, the reaction temperature is between 210 and 260 DEG C and the reaction time is 3 to 8h. The preparation method carries out esterification reaction and ester exchange reaction, and the esterification reaction has two stages so as to effectively reduce secondary reaction of 1,4 butanediol. A prepared product has a characteristic viscosity number above 1.2dl/g, a melting point controlled between 100 and 140 DEG C, a tensile strength between 18 and 37MPa and a breaking elongation ratio from 800 to 1,500 percent.

The invention discloses a water solution polymerization production method of dimethyl diallyl ammonium chloride and acrylamide copolymer, which uses cation industrial monomer DMDAAC and industrial non-ionic monomer AM prepared by industrial one-step method as raw materials, uses initiator via water solution polymerization to prepare dimethyl diallyl ammonium chloride and acrylamide copolymer, with high relative molecular weight and cation degree serialization. The invention uses cheap materials, has wide adjustable proportion between oxidant and reducer in initiator, and the application for initializing polymerization temperature of different cation degree PDA products. The invention has simple and mild reaction condition, while the PDA product cation degree is 5-99%, relative characteristic viscosity is 17.0-2.9dL/g, and residual monomer content is lower than 1%. The product has high cation degree serialization, high relative molecular weight of PDA product in each cation degree, strong adaptability, simple method, easy industrialization, and wide application in oil development, paper making, mining, weaving, dying, water treatment, and daily chemical or the like.

The invention discloses a biobased polyethylene terephthalate. The melting point of the biobased polyethylene terephthalate is between 255 and 270 DEG C, and the ethylene glycol in the raw materials is a biobased ethylene glycol, namely the carbon element in the ethylene glycol component of the raw materials is sourced from biological materials. The polyethylene terephthalate sourced from biobased materials has excellent performances, and the melting point, the diethylene glycol content, the terminal group content, the characteristic viscosity of the biobased polyethylene terephthalate are the same as those of the polyethylene terephthalate sourced from common petroleum based materials; moreover, the biobased polyethylene terephthalate also meets the requirements on environmental protection.

The present invention belongs to the preparation process of water base developing photosensitive polyimide material. Aromatic dialphanyl diacyl chloride, 3,5-diamino benzoic acid, 4, 4'-diamino-3, 3'-dihydroxy diphenyl methane and 4, 4'-diamino-3, 3'-dihydroxy diphenyl sulfone are polymerized to produce polyamate as one kind of imide prepolymer. The prepolymer has characteristic viscosity of 0.35-0.50, and when 2-diazo naphthoquinone derivative as photosensitizer is added, the prepolymer becomes excellent photosensitive material with high photosensitive performance, good filming performance and high heat resistance.

A polyaryl thioether sulfone is disclosed, which has the characteristic viscosity for its solution of 0.15-0.54, the vitrification temp higher than 210 deg.C, the thermal deformation temp higher than 180 deg.C and thermal decomposing temp higher than 480 deg.C and thermal decomposing temp higher than 480 deg.C. Its preparing process features that the halogenated aryl compound is added to the reaction system of Na2S.xH2O and bichlorodiphenyl sulfone, and composite catalyste and assistant are used.

The invention discloses a relative molecular mass controlled polyquaternium color fixing agent and a synthesizing method thereof. The method comprises the following steps: adding weighed industrial DMDAAC monomer into a reactor to prepare a reacting solution with the initial monomer solution mass fraction of between 35 percent and 65 percent; weighing initiator ammonium persulfate APS to prepare an initiator solution, and adding the mixture into a constant pressure funnel; heating the reacting solution, uniformly dropwise adding the ammonium persulfate initiator solution into the constant pressure funnel in a stirring state, preserving the temperature to keep on reacting after dropwise adding of the initiator is completed; and further heating and curing the reacting solution after temperature preservation so as to further improve the monomer conversion rate to obtain the relative molecular mass controlled polyquaternium color fixing agent PDMDAAC. The product has a specific range of characteristic viscosity values of between 0.25dL/g and 0.45dL/g, and has excellent color fixing performance; and the reacting monomer conversion rate is over 96.0 percent with high yield.

the invention discloses a preparing method of macromolecular aliphatic polyester, which is characterized by the following: proceeding melting polycondensation for diatomic alcohol and diacid; obtaining low-molecular hydroxy polyester prepolymer with even molecule at 2000-7000 or characteristic viscosity under 0.5; adopting aliphatic diacyl dilactone amide or aromatic diacyl dilactone amide to melt to expand chain; obtaining the product.

The invention relates to a composite catalyst suitable for preparation of polytrimethylene terephthalate, and a method for preparing polytrimethylene terephthalate by adopting the composite catalyst. The composite catalyst comprises tetra-n-butyl titanate and phosphite according to a preferable mass ratio of 0.6-1.15. Polytrimethylene terephthalate is prepared from terephthalic acid and 1,3-propylene glycol through an esterification reaction and a condensation polymerization reaction with the composite catalyst as a catalyst. Phosphate is added to the catalyst, so the catalysis activity of tetra-n-butyl titanate on the degradation reaction of PTT (polytrimethylene terephthalate) is effectively reduced, and the catalysis selectivity is improved; the composite catalyst used in the preparation of the PTT has the advantages of small amount, low cost, fast reaction speed, mild reaction conditions, and controllable reaction; and the characteristic viscosity of the PTT reaches 0.85-1.07dL/g, and the PTT is white in color.

In order for the viscosity of the engine oil to be determined as directly as possible, particularly in the case of a motor vehicle with hydraulic control of the gas exchange valves, provision is made for a time period which a hydraulic component, in particular a solenoid valve, requires to move from a first position to a second position to be used as a measure of the viscosity. In particular, an electrical control signal for the solenoid valve is evaluated in the process. An additional sensor arrangement is not required. The determined viscosity is preferably actively used for controlling the gas exchange valves.

A propylene-based resin composition has good external appearance due to good weld appearance and low gloss and has excellent mechanical properties such as impact resistance and stiffness. The composition is well-balanced in the external appearance and mechanical properties. Automotive interior trims made of the composition are also described. The propylene-based resin composition comprises (A) 60 to 90% by weight of a propylene-based resin (1) comprising 78 to 88% by weight of 23° C. p-xylene insolubles (a) and 12 to 22% by weight of 23° C. p-xylene solubles (b), (2) the insolubles (a) having an isotactic pentad fraction of 95% or higher, a relaxation time (τ) of 0.01 to 0.35 second at an angular frequency (ω) of 10°/sec when measured by melt viscoelastometry and a molecular weight distribution index (PDI) of 1 to 18 which is expressed by ω₂/10ω₁ wherein ω₁ is an angular frequency at which a storage modulus (G′) as measured by melt viscoelastometry is 2×10² Pa and ω₂ is an angular frequency at which a storage modulus (G′) as measured by melt viscoelastometry is 2×10⁴ Pa, and (3) the solubles (b) having an intrinsic viscosity [η] (in decalin at 135° C.) of 3.3 dl/g or higher and an ethylene unit content of 43% by weight or smaller; (B) 0 to 10% by weight of a rubberlike elastomer; and (C) 10 to 30% by weight of tale. The automotive interior trims are produced by injection-molding the composition.

A high-molecular disperser with 7.2-7.5 centipoises as characteristic viscosity features that the methoxy ethanediol is used as hydrophilic chain segment playing the space stabilizing role and the ester radical is used as anchor group of pigment. Its preparing process includes such steps as synthesizing coarse product, purifying and preparing final product.

The invention discloses a moisture-curing polyurethane hot-melt adhesive for manufacturing of composite boards, and belongs to the field of adhesives. The adhesive is prepared from the following raw materials: (a) a polyurethane prepolymer prepared through polymerization of isocyanate and polyhydric alcohols and (b) an acrylate polymer with a characteristic viscosity lower than 0.1. The adhesive has excellent bonding properties, is applicable to bonding of metallic and nonmetallic materials, and can be used for preparing high-performance metallic-nonmetallic composite boards.

The invention discloses a preparing method for PDMC with a high monomer conversion rate and serialized relative molecular mass. The amount of adopted monomer initial content coupling initiator is controlled for preparing the PDMC with the high monomer conversion rate and the serialized relative molecular mass, the monomer conversion rate of a serialized PDMC product obtained through preparation is larger than 98%, the characteristic viscosity value is 2.0-14.0 dL/g, a monomer is DMC, the mass fraction of the monomer is 35-70%, the initiator is water-soluble peroxide initiator, and the amount of the adopted initiator accounts for 0.20-2.00% of the mass fraction of the monomer. According to the method, the industrial product DMC concentrated, adsorbed, purified and cleaned is used as a raw material, a metal ion chelating agent and the water-soluble peroxide initiator are added under the nitrogen condition, and two-step temperature rising initiates polymerizing so that a target product can be generated. The obtained product serves as a positive ion water-soluble polymer with the high monomer conversion rate and the serialized relative molecular mass, is stable in quality, and is widely applied to multiple fields of oil exploitation, papermaking, mining, spinning and printing and dyeing, daily-use chemical industry, water treatment and the like.

The invention discloses a method for supercritically washing sea sand, river sand and hill sand, which mainly applies two-phase coexistence washing water formed by mixing gaseous ozone, carbonic acid gas and liquid water, overcomes the capillary phenomenon caused by physical characteristics viscosity and surface tension of water, and generates supercritical washing to remove substances on the surface of the sea sand which are harmful to cement, reinforcing steel bar and the like, such as chloride, sulfate, organic substances, algae and the like. The ozone as a strong oxidizing agent plays a role in decomposing the organic substances, so when high-concentration ozone water is used as washing water, the ozone water has high efficiency and low cost in removing harmful ions of the sea sand or the river sand, and has the characteristic of no harmful substance residue; and the washed sea sand does not have odor, and has low content of ash, and can become high quality sand for construction and engineering.

The invention discloses a monomer containing a benzimide phenylacetylene structure. The monomer can enable self-crosslinking chemical reaction of a synthesized polymer under high temperature. The monomer containing a benzimide phenylacetylene structure and the structural units represented by I and II for synthesis of polyester can undergo random copolymerization to obtain high temperature self-crosslinked copolyester, and when the copolyester contains a PET structural unit, the characteristic viscosity number [eta] is 0.44-1.38dL/g, the vertical combustion UL-94 grade is from V-2 to V-0, the oxygen index LOI is 24.0-35.0%, and the cone calorimeter test peak heat release rate PHRR and the smoke release total amount are both lower than pure polyester. The invention also discloses a preparation method of the copolyester. The benzimide and phenylacetylene in the copolyester involved in the invention can generate synergistic cross-linking effect, so that the copolyester has very high flame-retardant and anti-dripping efficiency, and also the copolyester is endowed with excellent flame retardant, anti-dripping and smoke suppressing performance. The method provided by the invention is basically consistent with the synthesis method of conventional polyester, not only is mature in technology, and easy and convenient to operate, but also is easy to control and convenient for industrial production.

The present invention relates to absorbable block copolymers with improved characteristics including thermal stability, molecular weight consistency, inherent viscosity retention following melt extrusion, and fibers made from the polymers exhibit increased strength.