18 results about "Residual monomer" patented technology

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.

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 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.

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.

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.

This invention discloses a continuous dynamic high-efficiency devolatilization method for a polymer / volatile fraction system based on a high mass transfer interface, comprising the following steps: using a single-screw dynamic devolatilizer, adding a polymer solution to the devolatilizer, the polymer solution comprising devolatilized polymer and volatile small molecules, the volatile small molecules including organic solvents, residual monomers, water, or reaction byproducts; the material in the devolatilization section is conveyed and compressed by the screw after devolatilization, and directly leaves the dynamic devolatilizer; or a side-feed extruder is set downstream of the devolatilization section, plastic additives are added to the devolatilized polymer melt, and melt-blended with the raw material polymer at the end of the dynamic single-screw devolatilizer before leaving the dynamic devolatilizer. This invention's continuous dynamic devolatilization method based on a high mass transfer interface is highly efficient, with the high efficiency stemming from the high mass transfer interface, which is derived from the design of the screw and shell structure in the forced flow zone. It can effectively reduce equipment investment and maintenance costs while achieving the same effect.

This suppresses outgassing and reduces the degradation of the optical properties of the cover glass. [Solution] The cover glass is provided on the surface of a glass substrate and has a fine uneven structure, and is equipped with an anti-reflective layer made of a cured product of a photocurable resin. The cured product of the photocurable resin is a polymer of a first monomer having a monofunctional (meth)acryloyl group and a second monomer having two or more functional (meth)acryloyl groups. The first monomer has either a cyclic structure consisting only of single bonds, or a cyclic structure consisting of single and multiple bonds, or both. The content of the first monomer relative to the total first and second monomers is 20% by mass or more and 50% by mass or less. The content of the second monomer relative to the total first and second monomers is 50% by mass or more and 80% by mass or less. The content of residual monomers derived from the first monomer contained in the polymer is 0.3% by mass or less.

This method suppresses the contamination of steam generated from boiler water containing polyacrylic acid compounds with aldehydes. [Solution] Water is supplied to the boiler 20 through the water supply path 13. The boiler 20 stores the water from the water supply path 13 as boiler water and generates steam by heating this boiler water. At this time, a water treatment agent containing a polyacrylic acid compound such as sodium polyacrylate, which functions as a scale inhibitor, is added from the chemical supply device 40 to the water supply from the water supply path 13 to the boiler 20, and the boiler 20 controls the copper concentration of the boiler water to 3 mg / L or less in the presence of the polyacrylic acid compound derived from the water treatment agent. It is particularly preferable to use a polyacrylic acid compound with a residual monomer content of 1.0 mass% or less and to control its presence in the boiler water to 10 to 300 mg / L.

This invention relates to a method for the catalytic preparation of 1,5-pentamethylene diisocyanate trimer, belonging to the field of organic synthesis and polymer materials technology. Addressing the problems of poor catalyst selectivity and the tendency to generate pentamers and higher polymers in existing PDI trimer synthesis processes, leading to increased product viscosity and decreased NCO content, this invention proposes using potassium isooctanoate catalyst under nitrogen protection. The purified PDI monomer is heated to 90°C, and 0.8‰ (based on the mass of PDI monomer) of catalyst is rapidly added dropwise. The reaction is controlled until the NCO conversion reaches 30%, then a terminator is added to terminate the reaction, followed by molecular distillation to remove residual monomers. Gel permeation chromatography (GPC) analysis shows that the obtained product contains 29.46% trimer, and the contents of pentamers, heptamers, and high polymers (n≥9) are 5.74%, 2.12%, and 5.90%, respectively. This invention achieves highly selective synthesis of PDI trimer, producing a product with low viscosity and high NCO content, which can be used as a curing agent for high-performance polyurethane coatings and has promising industrial application prospects.

The present application relates to the field of chemical or physical testing technology, and more particularly to a test system for residual monomers in photoresist resin, corresponding steps comprising: determining a target spectrum curve of a target sample, determining spectral characterization characteristic values of a target monomer by using absorption intensity of the target monomer in the target spectrum curve; determining key samples highly associated with the target monomer in a sample set by using similarity of the target monomer of any two samples in the sample set within a corresponding target wave number range; determining a comprehensive residual feature of the target sample by using each spectral characterization characteristic value in the target spectrum curve, determining a comprehensive residual intensity index of the target monomer in the corresponding sample set by using the key samples and the comprehensive residual feature; and determining a content detection result of the target monomer in the photoresist resin to be detected based on the comprehensive residual intensity index of the target monomer. Through the technical scheme of the present application, the detection accuracy of the content determination of the residual monomers in the photoresist resin is significantly improved.

This application provides a method for producing an isocyanate-terminated prepolymer, comprising the reaction of a polyisocyanate compound A) with an isocyanate-reactive compound B), and may include a subsequent step to reduce the residual monomer content, wherein the polyisocyanate compound A) comprises at least 30% by weight, preferably at least 50% by weight, and more preferably at least 70% by weight of pentamethylene diisocyanate relative to the weight of polyisocyanate compound A), and the isocyanate-reactive compound B) comprises at least 80% by weight of isocyanate-reactive compound B) comprising (I) poly(1,3-propanediol) having a number average molar mass in the range of 100 g / mol to 1300 g / mol, or (II) poly(ε-caprolactone) having an OH functional value of 2 and a number average molar mass in the range of 160 g / mol to 800 g / mol, or (III) any combination of (I) and (II).

The invention relates to a method for reducing the residual monomer content in a polymer composition, a polymer composition, a radically polymerizable composition, a polymer production method, a polymer and use.

This invention provides a method for reducing residual monomers and metal impurities in photoresist resin, comprising the following steps: S1. Polymerizing acetoxystyrene, tert-butyl acrylate, styrene, hydroxyethyl methacrylate, solvent, and initiator to obtain a photoresist resin; S2. Adding a metal salt catalyst and an organic acid to the photoresist resin prepared in step S1, and reacting by heating; S3. After the reaction is complete, cooling down, adding the mixed solution dropwise to a poor solvent to precipitate, obtaining a precipitated resin; S4. Adding a polar organic solvent to the precipitated resin to dissolve it, stirring to dissolve, and filtering to obtain a filtered resin solution; S5. Adding an amino acid aqueous solution to the filtered resin solution, stirring evenly, separating the aqueous phase, and retaining the organic phase solution; S6. Distilling the organic phase under reduced pressure to obtain a solid resin. This invention can control the total metal impurities to below 100 ppb, meeting the requirements of photoresist formulations for resin.

This invention relates to the field of chemical synthesis technology, specifically to a method for preparing low-impurity pharmaceutical-grade polyvinylpyrrolidone. The method involves mixing water, a catalyst, ammonia, and N-vinylpyrrolidone monomer to remove oxygen, heating under nitrogen protection, and then adding hydrogen peroxide to initiate polymerization. During polymerization, ammonia is used to control the pH value, maintaining the temperature until the desired conversion rate is achieved. Excess ammonia is then removed by vacuum extraction, followed by the addition of acidified cation exchange resin to adjust the pH. The mixture is then kept at a constant temperature and stirred to reduce residual monomer to below 10 ppm. Finally, the cation exchange resin is filtered off, and the product is spray-dried to obtain the final product. This invention provides a safe and efficient preparation process, producing a product with low residual monomer, a colorless and transparent appearance, few impurities, and low ash and peroxide content.

The application discloses a preparation method of an aqueous acrylic acid suspension thickening emulsion. When the residual monomer of a soft monomer is 200-1000 ppm in the preparation process, the soft monomer is supplemented into a reaction kettle, and then the reaction is continuously carried out. By using the method, the production stability and product performance are fully balanced, the obtained emulsion has good repeatability in industrial production, and the thickening agent prepared through the process has excellent suspension thickening performance and transparency.

The application discloses a method for preparing an interpenetrating network type polyurethane modified acrylate dispersion, and comprises the following steps: preparing a polyurethane prepolymer by carrying out a one-stage prepolymerization reaction on a mixed solution containing a polyol / crosslinking chain extender / acrylate monomer 1 and an isocyanate mixed solution; then, preparing an interpenetrating network type polyurethane modified hybrid resin by reacting the polyurethane prepolymer with an initiator / acrylate monomer 2 mixed solution; finally, neutralizing, dispersing and eliminating residual monomers to obtain the interpenetrating network type polyurethane modified acrylate water dispersion. The method realizes efficient interpenetrating hybridization of polyurethane and acrylate, perfectly combines the advantages of polyurethane and acrylate, and prepares the polyurethane modified acrylate under a low-solvent / solvent-free condition, so that the solvent removing process is omitted, the environment is friendly, and the energy consumption in the production process is greatly reduced; and continuous production realizes large-batch and high-quality stable production.

The application relates to the technical field of high polymer material processing, and discloses a method for integrally preparing optical PMMA through supercritical CO2 assisted devolatilization and microporous foaming, which comprises the following steps: conveying PMMA prepolymer containing residual methyl methacrylate monomers into a high-pressure reaction kettle to be contacted with and saturated by supercritical CO2; then rapidly reducing the pressure of the saturated melt to make CO2 dissolved in the melt precipitate to form a microporous structure and simultaneously take out the residual monomers; and finally cooling and shaping to obtain optical PMMA material. By adopting the method, the integrally preparation of high-efficiency removal of PMMA residual monomers and microporous 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.