58results about How to "Less residual monomer" patented technology

The invention discloses a pure-acrylic emulsion with low VOC and a preparation method thereof. The pure-acrylic emulsion is mainly used for preparing indoor paint and the formulation thereof comprises: 20-25% of methyl methacrylate, 10-15% of butyl acrylate, 7-10% of ethyl hexyl acrylate, 0.5-1% of crylic acid, 1-5% of emulsifier, 0.3-0.5% of persulfate, 0.2-0.3 of oxidant, 0.15-0.25% of reducing agent and 53% of water. The preparation method comprises the following steps: selecting monomers with similar reactivity ratio to carry out emulsion polymerization, and then adopting a redox system to carry out after-treatment on the emulsion so as to further reduce the content of residual monomers. According to measurement, the VOC content of the polymerization emulsion is less than or equal to 30(g / L) and far below the national regulation.

The invention belongs to the field of organic polymers and particularly relates to a method for preparing polyacrylonitrile spinning solution. The method comprises the following steps of: mixing the dimethyl sulfoxide solution of acrylonitrile, itaconic acid and methyl acrylate which serve as comonomers with the dimethyl sulfoxide solution of azo-bis-iso-heptonitrile, wherein the concentrations of the comonomers are12-20%, the concentration of the azo-bis-iso-heptonitrile is 0.1-1%, and the molar ratio of the acrylonitrile, the itaconic acid and the methyl acrylate is (96-99):(0.5-3):(0.5-3); carrying out polymerization reaction at the temperature of 50-80 DEG C; controlling the temperature at 60-80 DEG C 5-10 hours later; continuing to stir and extracting a polymer solution in a polymerizing kettle in vacuum until the vacuum degree in the polymerizing kettle is -80kPa; increasing the vacuum degree in the polymerizing kettle to -98kPa after extracting for 1 hour; continuing to extract; feeding the polymer solution extracted in vacuum into a defoaming kettle; continuously defoaming under the condition of -80kPa and 60-80 DEG C; and carrying out tertiary filtering on a defoamed polymer. The method is simple in process and high in controllability, and the content of solid in the prepared spinning solution is large, and the content of residual monomers is low.

The invention relates to a polynary scale and corrosion inhibiting agent and a preparation method thereof, in particular to a propenol itaconic acid sulfonate multipolymer scale inhibitin agent and a preparation method thereof. The scale inhibiting agent is characterized by being prepared from propenol, itaconic acid and sulfonate through aqueous polymerization under an initiating agent system, wherein by taking the mass of the itaconic acid as a reference, the addition of the sulfonate is 10-50 percent, the addition of the propenyl is 5-20 percent, the addition of the initiating agent is 5-30 percent, and the addition of sodium hypophosphite is 5-30 percent. In the invention, the itaconic acid is used as a raw material and is subjected to the aqueous polymerization with the propenyl and the sulfonate, and the invention has simple production process, fewer product residual monomers and no three waste exhausts. A polymer prepared by using the method has high-efficiency inhibiting effect on the formation and the adhesion of scale layers of carbonates, sulfates, phosphates, silicates, and the like in a cooling water system and good dispersant effect on iron oxide, sludge, and the like.

The invention discloses a method for preparing emulsion for a self-crosslinked waterborne wood coating. The emulsion comprises a component A and a component B. The method is characterized in that the preparation process comprises the following steps of a, for the component A, preparing acrylic resin with a high acid value containing air dry vegetable oil fatty acid composition, wherein the acid value is 180-240mgKOH / g; b, for the component B, preparing the acrylic resin with a high hydroxyl value, wherein the hydroxyl value is 120-260mgKOH / g; c, carrying out esterification reaction between the acrylic resin (component A) with the high acid value and the acrylic resin (component B) with the high hydroxyl value, neutralizing with ammonia (or amine) and diluting with water after the acid value is qualified, so as to obtain the emulsion C for the self-crosslinked waterborne wood coating. The emulsion can be used for preparing the self-crosslinked waterborne wood coating. The paint is low in VOC (volatile organic compound) content, accords with the environmental protection requirement, belongs to the environment friendly type, and can be widely applied to furniture coating and house decoration.

The invention provides a thermal expansibility microsphere and a method for reducing residual monomers therein. The method comprises a re-initiation step of supplementing an initiating agent of the residual monomers in a process of preparing the thermal expansibility microsphere by using a suspension polymerization method, wherein the initiating agent of the residual monomers is an oxidation reduction initiator system. The preparation method of the thermal expansibility microsphere, provided by the invention comprises the following steps: preparation of a water phase, preparation of an oil phase, suspension polymerization and residual monomer reduction. The technical scheme provided by the invention realizes quick reduction of the residual monomers under a low-temperature condition, is simple in production process, low in consumption and short in processing time, and simultaneously can efficiently reduce the content of the residual monomers in the thermal expansibility microsphere and a suspension reaction medium. The thermal expansibility microsphere prepared by using the method contains a little number of residual monomers and is small in pollution.

The invention discloses a water-absorbent resin and a preparation method, the method comprises the following steps: 1)adding a cross-linking agent and a polymerization initiator in an acrylic acid monomer alkaline aqueous solution; 2)applying microwave to initiate a polymerization; 3)performing polymerization for 3-10 minutes at 100-140 DEG C, increasing the temperature of 10-30 DEG C and slaking for 10-20 minutes to obtain a polymer gel; 4)sprinkling water vapor on the surface of the polymer gel to obtain the water-absorbent gel, by metering weight of the polymerization material, wherein the water vapor amount is 1-3weight%; and 5)using microwave for irradiate the water-absorbent gel under temperature which is lower than water boiling temperature.

The invention discloses impact polystyrene with the capacity scale of 50,000 tons or above as well as equipment and a production process of the impact polystyrene. More than 90% of the components of the rubber modified polystyrene product are represented by the formula, n is the polymerization degree, the range of n is 600-7000, and n is different along with different types of products; in addition to the main components, the rubber composition also contains 3-10% of butadiene rubber for modification, 0-7% of white oil, 0-1% of an additive of stearate, and a small amount of an organic residue such as a monomer (the total amount is 800 ppm or less). The modified polystyrene has good impact strength, the vicat softening point is 92-106 DEG C, the tensile strength of the modified polystyrene is 22-45 MPa at normal temperature, and the modified polystyrene is a thermoplastic material with good toughness. No process waste water is generated in the production process, all the raw materials are recycled, a small amount of generated process waste gas reaches the standard and is discharged after being subjected to condensation and adsorption treatment of special equipment, and the good environment-friendly, energy-saving and consumption-reducing effects can be achieved.

The invention discloses a method for producing a low-residue monoacrylamide polymer. The method comprises the following steps: preparing a polymerization solution containing acrylamide, an ionic monomer, an auxiliary material, a solvent, a pH value regulator and an initiator; placing the polymerization solution on a polymerization belt which is protected by a gas and is continuously conveyed; carrying out low temperature-to-high temperature stepped initiation on the polymerization solution placed on the polymerization belt by using a composite initiator, wherein the composite initiator comprises a low-temperature photoinitiator and a medium-high-temperature polyazo initiator; and performing microwave radiation when the temperature in the reaction reaches the highest temperature or the temperature of a rubber block is reduced to achieve heat insulation of the rubber block. The photo-initiation and polyazo stepped initiation system and microwave radiation heat insulation are adopted, sothe synthesized product has the advantages of low residual monomer, low crosslinking degree, good solubility, simple process and easiness in industrial production.

There is provided a liquid crystal composition that exhibits a sufficiently low viscosity (η), a sufficiently low rotational viscosity (γ1), and a large elastic modulus (K33) without decreasing the refractive index anisotropy (Δn) and the nematic phase-isotropic liquid phase transition temperature (Tni) and without increasing the solid phase-nematic phase transition temperature (Tcn). The liquid crystal display element that uses this liquid crystal composition satisfactorily obtains a pretilt angle and has a high voltage holding ratio (VHR) and high-speed response. Thus, a liquid crystal display element that has no or less alignment defects and display defects such as image sticking, and has high display quality and high response speed is obtained.

The invention relates to a dimethyl itaconate sulfonate multi-copolymer scale inhibitor and a preparation method thereof, which belong to the technical field of chemical industry. The scale inhibitor is prepared by performing aqueous polymerization on dimethyl itaconate, itaconic acid and sulfonate under an initiator system. Based on the mass of the itaconic acid, the adding amount of the sulfonate is between 10 and 50 percent, the adding amount of the dimethyl itaconate is between 5 and 100 percent, the initiator content is between 5 and 30 percent and sodium hypophosphite is between 5 and 30 percent. The itaconic acid serving as a raw material undergoes aqueous solution free radical polymerization with the dimethyl itaconate and the sulfonate in the presence of the initiator, so that production process is simple, the product has a small quantity of residual monomers and three wastes are not discharged. The polymer prepared by the method has efficient inhibitory action on the formation and attachment of fouling layers such as carbonate, sulphate, phosphate, silicate and the like in a cooling water system and plays a good role in dispersing iron oxide, sludge and the like.

The invention discloses a coating thickener which is prepared from the following raw materials in parts by weight: 25-35 parts of acrylic acid, 15-25 parts of hydroxyethyl cellulose, 10-20 parts of stearic acid, 2-7 parts of sodium dodecyl benzene sulfonate, 0.2-4 parts of an initiator and 80-100 parts of solvent oil. The coating thickener disclosed by the invention is remarkable in thickening effect, can be combined with various coatings, is few in residual monomer and has a self-thickening property, and the thickener is convenient in color base preparation, good in stability, free of crust on the surface and good in compatibility with coatings and has good stability.

The invention discloses a preparation method of amphoteric polyacrylamide dispersion liquid. The preparation method comprises the following steps: putting a main functional monomer into a mixed system comprising an amphoteric dispersion stabilizer, a chelating agent, a pH regulator and inorganic salt deionized water solution; initiating a reaction by virtue of an initiating agent; and preparing the amphoteric polyacrylamide dispersion liquid by virtue of a dispersion polymerization method. The dispersion liquid prepared by adopting a novel amphoteric polymer dispersion stabilizer has the characteristics of good stability, high molecular weight, high dissolution rate and the like, and a synthetic process of the dispersion liquid is environment-friendly and pollution-free and is low in energy consumption, and the product is nontoxic and noncorrosive, cannot generate secondary pollution and accords with the development direction of green and environment-friendly chemical assistants. The amphoteric polyacrylamide dispersion liquid has an application prospect in the fields of water treatment, papermaking, printing and dyeing, oil fields, mining, daily chemicals and the like.

The invention relates to a multiple scale-resisting corrosion inhibitor, in particular to an ether-based itaconic acid sulfonate type multi-copolymer scale inhibitor and a method for preparing the same. The scale inhibitor is characterized by being prepared by the aqueous polymerization of alpha-allyl glyceroether, itaconic acid and sulfonate in an initiator system; and based on the mass of the itaconic acid, the additive amount of the sulfonate is 10 to 50 percent, the additive amount of the alpha-allyl glyceroether is 5 to 20 percent, the initiator content is 5 to 30 percent, and the additive amount of sodium hypophosphite is 5 to 30 percent. In the method, the itaconic acid serving as the raw material undergoes aqueous polymerization with the alpha-allyl glyceroether and the sulfonate,the production process is simple, residual monomers of the product is little, and three-wastes are not emitted; and the polymer prepared by the method can efficiently inhibit formation and adhesion of the scale layer such as carbonate, sulfate, phosphate and silicate, and better disperse iron oxide, sludge and the like.