106 results about "Residual monomer" patented technology

The invention discloses a preparation method of EVOH, and relates to the technical field of EVOH. According to the method, a low-temperature (0-5 DEG C) methanol-n-hexane mixed solvent system is creatively adopted and matched with a penetration enhancer to realize synergistic extraction, so that synchronous and deep removal of polar and non-polar small molecular impurities in the EVA is finally realized, the content of impurities in the EVA is remarkably reduced, and the self-polymerization reaction of residual monomers is effectively inhibited; therefore, a key guarantee is provided for subsequent preparation of high-quality EVOH products. The film processed by the EVOH prepared by the invention has the characteristics of few crystal points and high product quality, and can be applied to the field of high-barrier packaging film materials.

The invention discloses a multi-stage devolatilization process method for optical-grade PMMA (polymethyl methacrylate), which comprises four stages of devolatilization stages, specifically, a first-stage flash devolatilization stage, a second-stage vacuum devolatilization stage, a third-stage high-vacuum devolatilization stage and a fourth-stage high-temperature low-vacuum short-distance devolatilization stage. According to the multi-stage devolatilization process method of the optical-grade PMMA, deep devolatilization can be carried out on the PMMA resin, and the obtained PMMA resin has low haze and low residual monomer amount.

The invention discloses a low-cost ammonia-free waterproof emulsion as well as a preparation method and an application method thereof, and belongs to the technical field of cement coatings. Comprising the following steps: mixing and stirring an emulsifier, a monomer and deionized water to obtain a pre-emulsion; adding deionized water into the reaction kettle to obtain a kettle bottom material; adding 0.9% of the pre-emulsion and an initiator a into the kettle bottom material in a stirring state, dropwise adding the rest of the pre-emulsion and the initiator b at the same time after 15 minutes, controlling the pre-emulsion and the initiator b to be dropwise added at the same time, and keeping the temperature after dropwise adding is finished; adding an oxidizing agent and a reducing agent to eliminate residual monomers, then adding a neutralizing agent to adjust the pH value, and adding an auxiliary agent; wherein the emulsifier comprises an anionic emulsifier and a nonionic emulsifier in a mass ratio of (2-3): 1; the monomers comprise styrene, butyl acrylate and functional monomers, and the functional monomers are hydroxyethyl acrylate and beta-acryloyloxypropionic acid. The low-cost ammonia-free polymer cement waterproof coating prepared from the emulsion disclosed by the invention has the advantages of low cost, environmental friendliness, good constructability and excellent mechanical properties.

The invention relates to a method for reducing the content of residual monomers in a polymer composition, the polymer composition, a composition capable of free radical polymerization, a polymer preparation method, a polymer and application.

A super-wet surface is a polypropylene surface, on which a hydrophilic side group is grafted, having a micro-nano structure. The super-wet surface is at least super-hydrophilic and does not contain an initiator residue. The super-wet surface is prepared by grafting, in the absence of an initiator, by means of microwave irradiation, a monomer for forming a side group, on the polypropylene surface, as a grafting base, having a micro-nano structure. In the preparation of the super-wet surface, the molecular weight of polypropylene does not decrease after grafting, there is no residual monomer or initiator residue, and the super-wetting effect of the obtained surface is lasting and stable. The super-wet surface can be used in bonding, spraying, oil-water separation, water treatment, biology, medicine and energy fields.

The present invention relates to a process for preparation of an ABS graft copolymer. The process comprises (i) grafting a butadiene latex with a gel content in a range from 75% to 90% with a first portion of acrylonitrile and styrene monomers in a percentage ratio in a range from 1.4 to 1.6, in presence of an initiator- 1 and a molecular weight regulator, carrying out the polymerization for 0.5 hours to 1.5 hours, (ii) adding a second portion of acrylonitrile and styrene, additional initiator- 1 and molecular weight regulator to step (i), and continuing polymerization for 3 hours to 5 hours, and (iii) additionally adding the initiator- 1 or an initiator-2 to step (ii), and continuing polymerization for 1 hour to 2 hours. The feeding pattern of monomers in the process provides a high polymerization rate and thereby reduces residual monomer content.

The application discloses a preparation process of high-adhesion EB electron beam curing display cover plate ink, and relates to the technical field of ink preparation. The process uses high-functionality acrylate monomers, polyurethane acrylate prepolymers and an interface coupling agent as main components, realizes excellent adhesion and abrasion resistance to glass and plastic substrates through electron beam irradiation and rapid curing, and meets the requirement of high light transmittance. The process overcomes the problems of insufficient adhesion and high residual monomer of the existing EB curing ink, improves the comprehensive performance of the EB curing ink, and is suitable for the field of high-end display cover plate printing and manufacturing.

The invention discloses an amphiphilic disulfide and a preparation method and application thereof, and belongs to the technical field of emulsion polymerization, the disulfide has the following structural general formula (I), in the formula (I), R1 is C1-C6 straight chain or branched chain alkyl; r2 is C2-C6 straight chain or branched chain alkyl; M1 is alkali metal ion or NH4 < + >; and M2 is alkali metal ion. A redox system formed by the disulfide and an oxidizing agent is used for post-treatment of a polymerized emulsion, residual monomers and free radicals in the emulsion can be efficiently cleared in a targeted mode, excellent emulsion stability is kept, and formaldehyde is not released.

The application discloses a kind of binder for lithium battery separator cold pressing process and preparation method thereof, it is related to lithium battery separator binder technical field, binder includes the following component is made: acid monomer, amide monomer, nitrile monomer, acrylic ester monomer, ether bond containing multifunctional monomer, long side chain hydrocarbon chain monomer, neutralizing agent, initiator.Preparation method includes the following steps: after mixing binder component, it is formed into mixed solution in deionized water;Nitrogen protection is added to initiator, heating reaction;After reaction is completed, neutralizing agent is added to adjust pH value, dilution and vacuum removal residual monomer are obtained after.The application forms three-dimensional network structure by introducing ether bond containing multifunctional monomer, reduces cohesion, makes dry film soft, adapts 25 DEG C cold pressing process;While introducing long side chain hydrocarbon chain monomer improves compatibility and wettability with PE / PP separator, realizes low energy consumption cold pressing bonding.

The application relates to the technical field of oilfield chemicals, and discloses a temperature-resistant and salt-resistant cationic hydrophobic association polymer as well as a preparation method and application thereof. Components of the polymer are acrylamide, N,N-dimethyl-N-methyl acryloyloxyethyl-N-2-hydroxy-1-octadecylamino propyl ammonium chloride, ammonium persulfate, sodium bisulfite, a fatty alcohol polyoxyethylene ether and a solvent. The application chemically synthesizes specific amounts of acrylamide, N,N-dimethyl-N-methyl acryloyloxyethyl-N-2-hydroxy-1-octadecylamino propyl ammonium chloride, ammonium persulfate, sodium bisulfite and the fatty alcohol polyoxyethylene ether, and can prepare the polymer with high thickening efficiency. The polymer has good thickening performance, a small critical association concentration, excellent temperature resistance and salt resistance, and can be applied to unconventional oilfields. The product produced by the preparation method has low residual monomer content, the preparation process is simple, the cost is low, the operation is easy, the pollution is small, and the product is easy to be industrially produced.

This invention provides a continuous, dynamic, and efficient defloration method for polymer / volatile component systems based on high mass transfer interfaces. [Solution] The method includes the steps of adding a polymer solution to a single-screw dynamic defoliation apparatus, wherein the polymer solution contains a defoliated polymer and volatile small molecule substances, the volatile small molecule substances containing an organic solvent, residual monomer, water, or reaction by-products, and after the material in the defoliation section is defoliated, it is conveyed and compressed by a screw and then removed from the single-screw dynamic defoliation apparatus, or providing a side-feed extruder downstream of the defoliation section, adding a plastic additive to the defoliated polymer molten body, melting and mixing it with the defoliated polymer molten body at the end of the single-screw dynamic defoliation apparatus, and then removing it from the dynamic defoliation apparatus.

The invention provides a low-precipitation high-transparency high-toughness polyamide material as well as a preparation method and application thereof. The polyamide material comprises polyamide and a specific small molecule capturing agent. According to the low-precipitation, high-transparency and high-toughness polyamide material disclosed by the invention, residual monomers and oligomers of polyamide are reduced in the production process, so that the precipitation resistance problem is obviously improved, the high transparency of the material is maintained, the low-temperature toughness resistance is realized, and the application range in the fields of medium storage and transportation can be widened.

The invention discloses a method for detecting residual monomers in vinyl chloride-vinyl acetate copolymer resin, which comprises the following steps: S1, filling an external standard solution into a headspace sample bottle, sealing, detecting by adopting HS-GC-MS, and drawing a content-peak area standard curve of a target monomer by adopting an external standard method; s2, mixing to-be-detected vinyl chloride-vinyl acetate copolymer resin with a solvent A, dissolving the to-be-detected vinyl chloride-vinyl acetate copolymer resin to obtain a to-be-detected solution, detecting the to-be-detected solution by adopting HS-GC-MS, and calculating the content of a target monomer in the to-be-detected vinyl chloride-vinyl acetate copolymer resin by combining the peak area of the target monomer and the content-peak area standard curve, by adopting HS-GC-MS, the volatile residual monomer to be detected is firstly subjected to mass spectrum qualitative recognition, and then quantitative analysis is carried out on the basis of qualitative confirmation; the method can synchronously realize quantitative determination of the vinyl chloride monomer and the vinyl acetate monomer in one-time detection.

The present invention relates to a method comprising the steps of: a) contacting styrene and an ethylenically unsaturated monomer under emulsion polymerization conditions to form an aqueous dispersion of styrenic copolymer particles and residual monomers; and b) contacting the dispersion of the styrenic copolymer particles with a reductant and a t-C4-C10-alkyl hydroperoxide to reduce the concentration of residual monomers in the aqueous dispersion to less than 1000 ppm of residual monomers; wherein the mole-to-mole ratio of the t-C4-C10-alkyl hydroperoxide to reductant is in the range of from 3:1 to 50:1. The method of the present invention provides a way of preserving a styrenic latex even in the absence of a biocide.

The invention relates to the technical field of high polymer material processing, and discloses a supercritical CO2 assisted devolatilization and microcellular foaming integrated method for preparing optical-grade PMMA (polymethyl methacrylate), which comprises the following steps: conveying a PMMA prepolymer containing a residual methyl methacrylate monomer into a high-pressure reaction kettle to be in contact with supercritical CO2 and saturated; then, the saturated melt is subjected to rapid pressure reduction, CO2 dissolved in the melt is separated out to form a micropore structure, and residual monomers are synchronously brought out; and cooling and shaping to obtain the optical-grade PMMA material. By adopting the method disclosed by the invention, integrated preparation of efficient removal of PMMA residual monomers and micropore lightweight forming can be realized at a lower processing temperature, and the obtained material has lower residual monomer content, lower density, higher light transmittance and lower haze.

The application provides a branched structure toughening agent and a preparation method and application thereof, and relates to the technical field of polymer modification, and particularly relates to a branched structure toughening agent and a preparation method and application thereof. The branched structure toughening agent is prepared by mixing an aromatic vinyl monomer, an acrylic ester monomer, an initiator and water, and then heating and polymerizing to obtain an intermediate; and then mixing the intermediate with a polyolefin elastomer, an initiator and an antioxidant, and then performing double-screw extrusion granulation. Compared with the existing linear structure toughening agent, the branched structure toughening agent has a larger free volume and a higher toughening efficiency; compared with the core-shell structure toughening agent, the preparation method is simpler, and the structure has a large degree of freedom. The branched structure toughening agent has the advantages of no need of using a solvent, less investment, easy acquisition of equipment, less discharge of a process route, simple process control, low residual monomer content of a product, stable composition, simple use of the product, and wide application in toughening modification of polylactic acid, polyester and polyamide materials, and wide use in medical treatment, packaging, household appliances, automobiles, aviation and other fields. The branched structure toughening agent has a very wide application prospect and industrial value.

The invention relates to the technical field of polyvinyl chloride reaction monitoring, and discloses a method for monitoring pressure drop and conversion rate in a polyvinyl chloride reaction process. The method comprises the following steps: carrying out reaction initialization, adding desalted water, a vinyl chloride monomer, an initiator, a dispersant and an auxiliary agent into a polymerization kettle, controlling the initial reaction temperature and the stirring speed, and starting a suspension polymerization reaction; when the suspension polymerization reaction is carried out until the conversion rate reaches a preset threshold value, acquiring pressure drop data in the polymerization kettle in real time through a pressure sensor; calculating a current conversion rate by applying a preset pressure drop-conversion rate model based on the obtained pressure drop data; according to the current conversion rate obtained through calculation, terminator adding operation is executed to control the reaction process; and after the reaction regulation is completed, recovering the residual monomer and carrying out post-treatment to finally obtain a polyvinyl chloride resin finished product. The method is helpful for improving the stability and the product quality of polyvinyl chloride production.

The present invention provides a label having excellent barrier property and transparency, wherein contamination of the container and adhesive residue due to the residual monomer in the adhesive layer are suppressed. The label is a label that is used for shrink-wrapping a container body of a resin container by wrapping around a barrel of the container body and heat-shrinking the shrinkable label, wherein the label comprises at least one heat shrinkable base material, a transparent vapor-deposited film consisting of an inorganic oxide, and an adhesive layer, and the adhesive layer comprises an adhesive composition comprising a triblock copolymer having a block structure of segment A1-segment B-segment A2.

The application discloses a devolatilization and granulation device for a styrene polymer, which comprises a primary devolatilizer and a secondary devolatilizer; a feeding end of the primary devolatilizer is connected with a first pipeline for receiving material to be devolatilized; a discharging end of the primary devolatilizer is connected with the secondary devolatilizer through a second pipeline; the primary devolatilizer is connected with a first vacuum device through a third pipeline and is connected with a fourth pipeline for receiving nitrogen; a first flow meter is arranged on the first pipeline, a first control valve is arranged on the third pipeline, and a second control valve is arranged on the fourth pipeline; the first flow meter is connected with the first control valve and the second control valve through a pressure indication controller and forms a flow pressure regulating loop, which is used for adjusting the pressure in the primary devolatilizer according to the flow of the material to be devolatilized, and then determining the devolatilization ratio of the primary devolatilizer according to the pressure in the primary devolatilizer, so that the feeding amount of the material entering the secondary devolatilizer and the components of the material are kept stable. The styrene polymer with high productivity and low residual monomer can be obtained.

An acrylic-imide copolymer including: an alkyl (meth)acrylate-based monomer unit; an aromatic vinyl-based monomer unit; and an imide-based monomer unit, wherein the copolymer includes a plurality of copolymer chains, a glass transition temperature is 109° C. to 133° C., the imide-based monomer unit is included in an amount of 20 parts by weight or less based on 100 parts by weight of an entire copolymer, and a residual monomer content in the copolymer is 1.3 wt % or less.

The invention discloses a preparation method of modified polyvinyl alcohol and modified polyvinyl alcohol, and belongs to the technical field of chemical synthesis, the preparation method comprises the following steps: adding vinyl acetate, a comonomer and methanol into a reaction kettle, heating to 55-65 DEG C, then adding a methanol solution of an initiator, then dropwise adding the methanol solution of the comonomer, and after dropwise adding is completed, reacting for 1-2 hours; after the reaction is completed, adding a methanol solution of sorbic acid to terminate the reaction, so as to obtain a polymer material; adding the polymer material into a rectification device, rectifying to remove residual monomers, and then adding methanol to obtain a resin solution; adding a sodium hydroxide methanol solution into the resin solution, heating to 40-60 DEG C, stirring and reacting for 20-60 minutes, and then drying to obtain the modified polyvinyl alcohol which is good in water solubility and stable in product quality.

The present invention relates to a process for preparing a polyester of glycerol and a dicarboxylic acid, the process comprising: (a) contacting monomers comprising at least glycerol and dicarboxylic acid in the presence of water in an inert atmosphere at a temperature of less than 100 DEG C wherein the molar ratio of glycerol / dicarboxylic acid ranges from 0.5 / 1 to 10 / 1; (b) carrying out esterification in an inert atmosphere at a temperature higher than 110 DEG C; (c) at a temperature higher than 110 DEG C, vacuumizing the reaction medium to a pressure lower than 100 mbar; (d) maintaining a vacuum and a temperature above 110 DEG C to carry out polycondensation, said process comprising: at the end of the esterification of step (b), before or after the evacuation of step (c), introducing a polycondensation catalyst in an amount of less than or equal to 5000 ppm with respect to the total weight of monomers, said catalyst being a tin-based food grade catalyst, the organic tin compounds are selected from organic tin compounds containing carboxyl functional groups (-C (O) OH), organic tin compounds containing functional groups (-Sn (O) OH) and mono-butyltin tris (2-ethylhexanoate). The present invention relates to a process for synthesizing glycerol polyesters having a residual monomer content of less than 5% by weight, based on the weight of the polymer, a high number average molar mass Mn of greater than 2500 g / mol, a dispersity of less than or equal to 10 and a 1, 2, 3-triacylglyceride unit content of less than 15 mol% with respect to all units of the polymer, in particular to the synthesis of glycerol polyesters having a residual monomer content of less than 5% by weight, based on the weight of the polymer, a high number average molar mass Mn of greater than 2500 g / mol.

The present invention relates to a method for producing superabsorbent particles having a low residual monomer content, wherein an aqueous monomer solution or monomer suspension is polymerised to form a polymer gel, the resulting polymer gel is optionally comminuted, the polymer gel is subsequently dried, and the dried polymer gel is optionally ground and classified, characterised in that phytic acid or a salt thereof is added prior to polymerisation.

The application discloses a method for continuously preparing a high-molecular water-absorbing resin at normal temperature and pressure in a closed mode, and belongs to the technical field of high-molecular water-absorbing resin preparation. The application provides a method for continuously preparing a high-molecular water-absorbing resin at normal temperature and pressure in a closed mode, which comprises the following steps: 1, preparing a reaction solution; 2, continuously filling the reaction solution into a plastic film bag to form a first pre-prepared body which is continuously output; and 3, continuously performing a closed polymerization reaction on the reaction solution in the film bag through UV radiation. The application realizes the closed and continuous preparation of the high-molecular water-absorbing resin at normal temperature and pressure, does not need to use heating and pressurizing equipment, and does not discharge gas during the preparation process; on the one hand, the product preparation cost is reduced; on the other hand, the cleanness, safety and stability of the preparation process are ensured. In addition, the continuous preparation method can greatly improve the product preparation efficiency and preparation scale, the monomer conversion rate of the product is high, the residual monomer is low, and the water absorption performance is excellent.

The invention discloses polysulfone resin as well as a preparation method and application thereof. The weight-average molecular weight Mw of the polysulfone resin ranges from 20000 to 200000, the content of cyclic dimers is smaller than 1.2 wt%, the content of residual monomers is smaller than 100 ppm, the content of K and Na ions is smaller than 60 ppm, the content of Fe and Cu ions is smaller than 10 ppm, the yellowness index YI does not exceed 12, and the light transmittance is larger than 85%. The polysulfone resin disclosed by the invention is obtained by taking a para-dihalogen diphenyl sulfone compound and a bisphenol A type compound or a 4, 4 '-biphenol type compound as raw materials, an aprotic polar solvent as a reaction solvent and inorganic salt as a salt-forming agent through polymerization by a nucleophilic substitution method. The method comprises the following steps: designing an incompatible solvent system, enabling resin powder to be in contact with an acidic aqueous solution containing a catalyst in a dissolved state, carrying out ring opening and degradation on a cyclic dimer through an interface reaction, simultaneously removing residual single and metal ions through extraction, and carrying out devolatilization and granulation on the purified resin powder to obtain the comprehensively purified polysulfone resin. The optical performance and the like influenced by the resin purity are greatly improved.

The invention provides maleic anhydride grafted modified polyolefin wax, a preparation method and application thereof, a hot melt adhesive and a preparation method thereof, and relates to the technical field of tackifiers for hot melt adhesives. The maleic anhydride grafted modified polypropylene wax is prepared from the following raw materials in parts by weight: 100 parts of polypropylene wax, 1 to 10 parts of maleic anhydride, 0.01 to 10 parts of a grafting auxiliary agent, 0.2 to 2 parts of an initiator, 0.4 to 4 parts of a diluent, 0.01 to 0.5 part of an antioxidant and 0.01 to 4 parts of an extracting agent. The maleic anhydride grafted modified polypropylene wax has the advantages of good fluidity, light color, high grafting rate, few residual monomers and low odor; the maleic anhydride grafted modified polypropylene wax meets the strict requirements of high-end scenes such as hot-melt sealants and environment-friendly building ink coatings for low-chromaticity and high-uniformity products for electronic and electrical appliances.

The present application provides a surface treatment agent having excellent antithrombogenicity and biocompatibility, and high hydrophilicity compared with conventional medical materials. The present application is an antithrombogenic material comprising a (meth)acrylate copolymer containing a hydrophobic (meth)acrylate and a hydrophilic (meth)acrylate, the hydrophobic (meth)acrylate being a silicone (meth)acrylate and / or a (meth)acrylic acid alkyl ester, the (meth)acrylate copolymer having a residual monomer amount of 4,000 ppm or less, an inherent viscosity (ηsp / c) of 0.18 dl / g or more and 3.00 dl / g or less, the (meth)acrylate copolymer being water-insoluble, and being a viscous liquid at room temperature.

This invention discloses a method for preparing a low-residue styrene-maleic anhydride copolymer resin, belonging to the field of polymer synthesis technology. The preparation method includes: dissolving styrene monomer, maleic anhydride monomer, and a bifunctional trithiocarbonate RAFT reagent in an organic solvent, and then performing RAFT controlled free radical polymerization via thermal or photoinitiation. The R group of the RAFT reagent contains a 4-dimethylaminopyridine structure, which directionally enriches maleic anhydride monomer around the polymerization active center through dynamic hydrogen bonding-ion pairing, forcibly forming an alternating copolymer structure; its Z group contains a substituted cyclohexyl peroxyketal structure, which can decompose in situ under thermal or photo-triggered conditions to generate initiating free radicals without the need for an external initiator. This method achieves precise control of the copolymer's molecular weight and sequence structure, resulting in a resin with low free reagent and monomer residues, controllable number-average molecular weight, and a small molecular weight distribution coefficient.

The invention relates to the technical field of coatings, and discloses an antibacterial UV-cured copolyester children water cup coating which is prepared from hexa-functionality and bifunctionality aliphatic polyurethane acrylate, isobornyl acrylate, a photoinitiator, a flatting agent and a ternary coordination antibacterial pre-solution. The preparation method comprises the following steps: dispersing zinc dimethacrylate in acetoacetic acid ethyl methacrylate and ethyl acetate, and dropwise adding hydroxyethyl methylacrylate phosphate under a mild condition to react, so as to obtain the zinc-beta-diketone-phosphate ternary coordination system. An indissolvable zinc salt is converted into an organic compatible form by utilizing a synergistic effect of acidolysis and chelation, so that the haze problem caused by poor dispersion of a zinc source is solved; and meanwhile, the Lewis acid catalysis characteristic of the zinc complex is utilized to initiate Michael addition reaction to deeply consume residual monomers. On the basis of ensuring high light transmittance of the coating and excellent adhesive force to a copolyester base material, high-efficiency antibacterial and low-monomer-residue safety are realized.

The present application relates to the technical field of paint chemical industry, and particularly relates to a preparation method of pentamethylene diisocyanate trimer, which comprises the following steps: (1) pre-catalysis: antioxidants and part of catalysts are put into pentamethylene diisocyanate for stirring at normal temperature, and vacuum degassing is carried out under negative pressure; (2) self-polymerization reaction: the remaining catalysts are added drop by drop into the monomer after degassing to initiate isocyanate self-polymerization; (3) fixed-point polymerization inhibition intervention: when the reaction reaches a certain specified conversion rate, a small amount of polymerization inhibitor is added to realize selective inhibition of the polymerization reaction; (4) termination treatment: when the stable polymerization reaches the end point, the polymerization is terminated by supplementing the polymerization inhibitor, and a thin film evaporator and a short path molecular still are used for purification. The preparation method has the advantages of high catalytic efficiency, stable polymerization and controllable product quality, the trimer content is higher than 60%, the residual monomer content is lower than 0.3%, and the green environmental protection requirement is met.