123results about How to "Improve polymerization stability" patented technology

The invention relates to a high-sealing polyacrylic ester dispersoid and a preparation method thereof; a multi-element emulsifier system which consists of an anionic emulsifier and a compound non-ionic emulsifier is adopted for controlling the charging process and components of the emulsifier in different polymerization periods, and the room-temperature self-crosslinking high-sealing polyacrylic ester dispersoid is prepared by a semi-continuous seeding emulsion polymerization process. The dispersoid has small particle size, good electrolyte-resistance (calcium ion) stability and high tolerance to various film forming accessory ingredients (various organic solvents with high boiling point). The dispersoid is used as seal coat of water-based wood coating and has good sealing performance to various woods; harmful volatile organic compounds (VOC) such as formaldehyde, and the like sealed against escaping from plates to pollute indoor environment, and the colored compounds such as turpentine, pine oil and tannin and the like are sealed against dissolving out of the plates to pollute pure top coating and white top coating of a water-based wooden ware; and in addition, the dispersoid can be used in water-based leather finishing agents.

The invention relates to a novel method for preparing a styrene-acrylate copolymer emulsion used in antirust primer paint. The method comprises steps that: (1) phosphate ester functional monomers are subject to a polymerization reaction; two hydroxyl groups of each phosphate ester group are subject to a chelation reaction on the metal surface, such that a dense phosphate ester (salt) protective film is formed on the metal surface, and water molecules and other salt ions are prevented from contacting the metal; the introduced phosphate ester group assists in improving the adhesion of painted coatings on metal surfaces, and in improving the antirust capacity of the painted coatings; (2) diacetone acrylamide (DAAM) and adipic dihydrazide (ADH) form a cross-linking system of the antirust emulsion; hydrazine groups in hydrazino-(NH2-NH2) and ketone groups in the DAAM (C=O) are subject to a dehydration condensation reaction, wherein the ketone groups are copolymerized on the copolymer; through outer cross-linking, a emulsion film with a three-dimensional reticular structure is obtained; (3) an emulsifying system is formed by combining a reactive anion emulsifier and a non-ion emulsifier, such that problems of emulsion deposition and gelling are solved. With the method provided by the invention, an aqueous emulsion with a high solid content is prepared, and water resistance and weathering resistance of the antirust paint is improved.

The invention relates to a preparation method of a fluorine-containing polyacrylate soap-free emulsion. According to the invention, the fluorine-containing polyacrylate soap-free emulsion is prepared by adopting an amphiphilic segmented copolymer polyacrylic acid-b-polyhexafluorobutyl acrylate (PAA-b-PHFBA) to substitute a routine emulsifier, and carrying out soap-free emulsion copolymerization on acrylate monomers, and can be applied to the leather field, the textile field, the coating field, the papermaking field, the adhesive field and the like. The compatibility of the hydrophobic segment of the used PAA-b-PHFBA and above prepolymerization monomers is good, so a problem of bad compatibility of fluorine-containing monomers is solved, thereby the stability of the emulsion polymerization process is substantially improved. Additionally, the PAA-b-PHFBA is anchored to emulsion particles in the emulsion polymerization, and the hydrophilic segment stretches into a water phase to stabilize the emulsion particles through an electrostatic effect and a steric hindrance effect, so the storage stability and the freeze-thaw resistance stability of the emulsion are improved, disadvantages of bad adhesion, bad water resistance and bad solvent resistance of films of common emulsions are overcome, and the mechanical properties, the adhesion and the abrasive resistance of the film of the emulsion are improved.

The present invention relates to a large-sized vinyl chloride seed with an average particle size of 0.65 to 1.5 μm, a vinyl chloride resin with improved low-viscosity properties, and preparation methods thereof. The preparation of the large-sized vinyl chloride seed includes adding a vinyl chloride monomer, an emulsifier, and a polymerization initiator to an aqueous medium; homogenizing the mixed solution using a rotor-stator type homogenizer; and subjecting the resultant monomer droplets to a polymerization reaction.

The invention provides butyronitrile latex with high nitrile group content for manufacturing asbestos or a non-asbestus sheet. The butyronitrile latex is prepared by taking butadiene and acrylonitrileas monomers and adopting a compound emulsifying system formed by an anionic emulsifier and a non-ionic emulsifier and a redox initiation system formed by persulfate and mercaptan. An intermediate-temperate emulsion polymerization technology of a three-stage stepped temperature control process that the monomers, an emulsifying agent, an initiating agent, a reducing agent, an auxiliary reducing agent, and the like are added in batches is adopted so as to ensure that the polymerization stability of the latex is greatly improved, prevent the generation of gel and improve the mechanical stabilityof the latex. The content of the acrylonitrile combined by the latex is 28-33 percent, and the strength in each aspect of the nitrile latex exceeds the strength of the prior nitrile latex product. Particularly, the butyronitrile latex has good oil resistivity and low loss ratio in a solvent, thus the nitrile latex has excellent performance when used for manufacturing the asbestos or the non-asbestes sheet.

Disclosed is an impact strength modifier (α) for a chlorine-containing resin, comprising a powder of a graft copolymer (A) obtained by graft polymerizing one or more kinds of vinyl monomers (b1) onto a polyorganosiloxane rubber (A1) or a composite rubber (A2) containing a polyorganosiloxane rubber and a polyalkyl(meth)acrylate rubber, wherein the specific surface area of the powder of the graft copolymer (A) measured by a nitrogen gas adsorption method is from 0.6 to 30 m²/g, and the pH of water used for extraction under conditions, in which (1) in an oven at 180° C., 5.0 g of the powder of the graft copolymer (A) is left to stand still and heated for 15 minutes, and (2) after the heating, the powder is dispersed in 100 ml of heated pure water and extracted for 1 hour at 70° C. while stirring, is from 4 to 11.

Provided is a vinyl alcohol-based copolymer, obtained by saponifying a copolymer of vinyl acetate and a polyfunctional monomer, wherein the polyfunctional monomer contains two or more ethylenic double bonds in its molecule, the vinyl alcohol-based copolymer has a side chain containing an ethylenic double bond and a molar ratio (d) of the ethylenic double bond to a total of vinyl alcohol units and vinyl acetate units is from 0.05/100 to 2/100, and the vinyl alcohol-based copolymer is water soluble.

The invention relates to a polymerizable surfactant which is prepared by the following steps: carrying out etherification reaction between a glycidyl ether compound and allyl alcohol or methallyl alcohol; and carrying out epoxy addition reaction on the product of the etherification reaction to obtain a nonionic surfactant with allyl or methyl allyl groups and an anion polymerizable surfactant derived from the nonionic surfactant. The polymerizable surfactant comprises two structures as shown in the formula (I) and the formula (II). In the formulas, R1 in the formula (I) and R1 in the formula (II) are alkyl, alkenyl, phenyl, alkyl phenyl, diphenyl and the like with 3-30 atoms, the R1 in the formula (I) and R1 in the formula (II) can be the same or not the same; R2 is hydrogen or methyl; A is alkylene with 2-4 carbon atoms; n is an integral number between 1 and 90; X is hydrogen or sulfate radical, phosphate radical and succinic acid radical; the polymerizable surfactant provided by the invention can provide excellent polymerization stability and mechanical stability and endows the emulsion film with excellent water resistence, cohesiveness and other properties. The formula (I) and the formula (II) are shown in the specification.

The invention provides a composition with functions of resistance and control of a nitrogen and phosphorus loss of protected horticultural vegetable fields and improvement of soil fertility. The composition comprises 30 to 50 parts of modified straw powder, 20 to 30 parts of biocoke, 15 to 25 parts of shell powder, 10 to 15 parts of bentonite, 5 to 10 parts of chitooligosaccharides and 10 to 15 parts of edible mushroom residues. Through use of strong adsorption of modified straw powder, chemical fixing action of shell powder to phosphorus, fixing action of bentonite to ammonium nitrogen, and denitrification transformation and microbial conversion of nitrate nitrogen based on denitrification bacteria in soil at a high carbon-nitrogen ratio, nitrogen and phosphorus effective use is improvedand the nitrogen and phosphorus loss can be effectively inhibited and controlled under synergism. The composition improves physico-chemical properties of soil and soil fertility, activates soil microbial activity, improves nitrogen and phosphorus availability of soil, reduces fertilizer application and saves a cost.

The invention provides an antibacterial cationic waterborne polyurethane resin and a preparation method thereof. The preparation method comprises the steps of: reacting macromolecular polyol with polyisocyanate at 80-95DEG C for 2-4h; then adding a small molecular alcohol chain extender and chlorogenic acid for reaction at 75-85DEG C for 1-3h; then adding a catalyst for reaction at 55-65DEG C for2-4h; adding a hydrophilic chain extender by starved charging technique, carrying out reaction at 35-45DEG C for 0.5-1.5h, performing cooling to a temperature ranging from -5DEG C to 5DEG C, adding aneutralizer for neutralizing, adding deionized emulsified water and dispersing the substances uniformly, and then conducting reduced pressure distillation so as to obtain the cationic waterborne polyurethane resin. According to the invention, chlorogenic acid is introduced to a cationic waterborne polyurethane molecular chain by chemical bonding, the influence of functional additives to the mechanical properties of waterborne polyurethane can be avoided, and also a good antibacterial effect can be realized.

The invention relates to an acrylamide polymerizable emulsifier with cations and non-ions and a preparation method thereof, belonging to the field of polymerizable emulsifier of the surfactant and a preparation thereof. The polymerizable emulsifier has not only cationic groups but also non-ion groups in structure so that the synergy of the two kinds of groups can be realized without combination. The specific solution is to adopt acrylic acid as starting material to perform chlorination reaction, acylation reaction, epichlorohydrin addition reaction and quaternization reaction to prepare the acrylamide cationic polymerizable emulsifier. The method has simple operation so that products with good application effectiveness can be obtained without purification. The product with the structure can control the HLB value of the synthesized surfactant by adjusting the epoxide addition number of polyoxyethylene ether, has good emulsifying performance and stability of polymerization and when using in emulsion polymerization, can be used to prepare a polymer emulsion with good performance. When the polymer emulsion is applied in coating, the coating can have antibacterial property without other added antimicrobial additives.

The invention belongs to the technical field of paint and discloses styrene acrylic emulsion and scrub-resistant high-PVC (pigment volume concentration) interior wall latex paint prepared from the same. According to the styrene acrylic emulsion, a semi-continuous seed emulsion polymerization method is adopted, a specific kind of crosslinking monomer is enabled to have a synergistic effect with an anionic/nonionic emulsifier and a functional polymeric monomer through controlling of the adding amount and the adding manner of the crosslinking monomer, and the emulsion polymerization stability and the compatibility of the emulsion with the components in the paint preparation formula are improved. The latex paint prepared from the styrene acrylic emulsion adopts a specific kind of anionic/nonionic composite thickener in combination with a specific paint preparation process, the obtained high-PVC interior wall latex paint has low content of VOC (volatile organic compound) and free formaldehyde and good alkali resistance and weather resistance, especially the scrub resistance times is 2-4 times of the scrub resistance times of the latex paint on the same grade, and good application prospect is realized.

The present invention relates to a protective film, a conductive laminate including the protective film, and a polarizing plate including the protective film, and provides the protective film which has peel strength controlled to be low, thus allowing for an easy removal of the protective film, which has an excellent polymerization stability and pot life, and may prevent a problem of an additive transfer to an adherend due to the additive.

The invention discloses carboxylic butadiene-styrene latex and a preparation technology thereof. The carboxylic butadiene-styrene latex is prepared from water phase materials, oil phase materials, priming materials, and other materials, wherein the water phase materials comprise a first solvent, a first emulsifier, acrylic acid, N-hydroxymethyl acrylamide, acrylamide and a pH (potential of hydrogen) regulator; the oil phase materials comprise styrene, butadiene and ethyl 3-mercaptobutyrate; the priming materials comprise mbs seed latex, sodium dodecyl benzene sulfonate, and a liquid alkaline mixture; the other materials comprise a fourth solvent, ethylenediaminetetraacetic acid disodium salt, an initiator mixture, a water-based defoamer, liquid alkaline, and a second emulsifier; the firstemulsifier selects an anion emulsifier; the second emulsifier selects a non-ionic emulsifier; the first solvent and the fourth solvent are respectively soft water. The prepared carboxylic butadiene-styrene latex has the advantages that the conversion rate is high, and the polymerizing stability, mechanical stability and chemical stability are good.

The invention provides an organosilicone modified copolymer emulsion tipping adhesive which is prepared from the following materials in parts by weight: 15 to 22 parts of vinyl acetate, 3 to 10 partsof polyvinyl alcohol, 10 to 25 parts of butyl acrylate, 3 to 12 parts of 2-ethylhexyl acrylate, 2 to 4 parts of acrylic acid, 3 to 12 parts of gamma-methylacryloyl oxypropyl trimethoxy silane, 2 to 5parts of vinyl triethoxysilane, 2 to 6 parts of vinyl trimethoxy silane, 4 to 11 parts of deionized water, 1 to 3 parts of a compound emulsifier and 3 to 10 parts of other additives. According to theorganosilicone modified copolymer emulsion tipping adhesive disclosed by the invention and a preparation method thereof, the viscosity and the storage stability are improved, and the rejection rate oftipped cigarettes is reduced.

The invention provides a rubber-type polymer for electronic material and manufacturing method thereof. The manufacturing method includes steps of using a surfactant as an emulsifying agent to carry emulsion polymerization and heating obtained polymer latex under the existence of electrolyte. The surfactant represented by a general formula (1) has HLB of 13.5 to 17.0 and cloud point of 1.0 mass% water solution more than 70 DEG C. In the general formula (1), R represents aliphatic alkyl of C8-C12, and n represents ethylene oxide average condensation number of 5-20. The manufacturing method of the present invention has advantages of excellent stability in polymerization process, high yield and low metal content.

There is provided a dispersion stabilizer for suspension polymerization comprising a vinyl alcohol polymer (A), wherein the vinyl alcohol polymer (A) has a terminal anionic group and has a saponification degree of 30 to 60 mol %, a viscosity average polymerization degree of 650 or less, and a proportion of polymer molecules having a molecular weight of 8000 or less as determined by gel permeation chromatography is 9.5% by mass or less. When a vinyl compound is suspension-polymerized using the dispersion stabilizer for suspension polymerization, its higher polymerization stability allows for providing particles having a uniform size with a less amount of coarse particles, even under the conditions favorable for unstable polymerization.