50results about How to "Low gel rate" patented technology

The invention relates to a preparation method of polar solution-polymerized styrene-butadiene rubber with low gel rate. The method involves grafting polar monomers on solution-polymerized styrene-butadiene rubber by means of free radical solution method, so as to change the polarity and further improve the interface bonding force of styrene-butadiene rubber and carbon black or white carbon black, so that the wet-skid resistance, wear resistance and dynamic mechanical property of vulcanized rubber are improved and the rolling resistance is reduced. The polar monomers used comprise maleic anhydride, acrylic acid, acrylamide, N-vinyl pyrrolidone and the like. The grafting rate of modified styrene-butadiene rubber is 1-5% and the gel rate is 1-3%; and the rubber polarity changes obviously.

The invention discloses waterborne silicone acrylate emulsion with a core-shell structure and a preparation method of the waterborne silicone acrylate emulsion. The acrylate emulsion is prepared from the following components: methyl methacrylate, butyl acrylate, acrylic acid, an emulsifier, an initiator, organosilicon, ammonium hydroxide and deionized water. A semi-continuous seed emulsion polymerization method is combined with a starved condition feeding production process, and all monomers are added into a polymerization system at different stages, so organosilicone acrylate emulsion with the core-shell structure is prepared. The waterborne silicone acrylate emulsion disclosed by the invention has no toxin or pollution and the advantages of the organosilicon and an acrylate polymer; hardness, adhesive force, thermal stability, hydrophobicity, water resistance and other properties of an emulsion film are improved; the film forming property, water resistance and pollution resistance of the emulsion are improved, and minimum film forming temperature and other properties of the emulsion are reduced; the gel rate of emulsion polymerization is effectively reduced, and conversion rate and stability of the emulsion polymerization are improved.

A preparing method of a modified acrylate emulsion is disclosed. The modified acrylate emulsion is prepared by subjecting acrylate, methacrylate, vinyl acetate, acrylonitrile, acrylic acid, an organosilicone modified monomer, a crosslinking monomer, a surface active monomer, and the like to emulsion polymerization. The organosilicone modified monomer is linear organopolysiloxane containing alkenyl bonding to silicon. Polymerization is performed after the surface active monomer, the acrylate and/or the methacrylate are adopted to prepare a seed emulsion, thus reducing the using amount of an emulsifying agent, making polymerization stable and making the gel rate low.

The invention relates to a silicon dioxide/polyacrylate/polysiloxane composite emulsion as well as a preparation method and application thereof. The preparation method mainly comprises the steps of silica sol modification, preparation of silicon dioxide/acrylate core-shell structure emulsion and preparation of silicon dioxide/acrylate/polysiloxane composite emulsion. The preparation method comprises the following steps: firstly, modifying silica sol, then preparing a composite emulsion with a more stable silicon dioxide/acrylate system and a low gel rate (less than 0.5%) by utilizing a seed growth polymerization method, and introducing active groups such as amino and epoxy into acrylate, so that the composite emulsion can be effectively assembled and compounded with subsequently added polysiloxane nanoparticles. Therefore, the raspberry-shaped silicon dioxide/acrylate/polysiloxane organic-inorganic hybrid emulsion with excellent performance is prepared. A silica component in the particles of the emulsion provides hardness support; the acrylate provides a film-forming property; the polysiloxane provides weather resistance, color retention and stain resistance.

The invention provides an epoxy organosiloxane modified acrylic emulsion and a preparation method thereof. The emulsion is specifically obtained by performing emulsion polymerization on an acrylic monomer, a single-end epoxy polysiloxane, an initiator, an emulsifier, a pH buffering agent and deionized water, wherein epoxy organosiloxane is a linear organopolysiloxane having an epoxy group bonded to silicon at one end. The invention further provides the preparation method of the modified acrylate emulsion; and the method comprises the steps of dissolving the single-end epoxy polysiloxane by using the acrylic monomer, preparing a pre-emulsion by emulsification, preparing a seed emulsion from acrylate and/or methacrylate and the emulsifier, and adding the pre-emulsion dropwise into the seed emulsion to complete the polymerization reaction. According to the method provided by the invention, the emulsion obtained by the method has good adhesion, surface hand feel, water resistance and stainresistance.

The present invention discloses shape memory material of co-mixed polyolefin/styrene elastomer. The shape memory material contains polyolefin 20-80 weight portions, styrene elastomer 20-80 weight portions, plasticizer 10-30 weight portions, chemical crosslinking agent 0.1-1 weight portions and co-crosslinking agent 1-10 weight portions. It has tensile strength not lower than 12 MPa, gel rate not higher than 10 wt%, restoring rate at 100 deg.c 80 not lower than wt%, fixing rate at 20 deg.c not lower than 80 wt%, restoring response temperature not lower than 30 deg.c and restoring period not more than 6 sec. The present invention also discloses the preparation process of the shape memory material.

The invention discloses core-shell type polysilsesquioxane/hydroxyl acrylate composite emulsion and a preparation method thereof. The preparation method comprises the following steps: by taking polysilsesquioxane as the core, performing cross-linking entanglement on a silane coupling agent polymer and an internal layer in the middle; by taking a hydroxyl functional monomer as a main functional monomer on the shell layer, performing copolymerization with other acrylic monomers, thereby obtaining the 'hard-core soft-shell' water-based hydroxyl acrylate emulsion. The composite emulsion disclosedby the invention is composed of three parts, namely the core, the intermediate layer and the shell, the core is the polysilsesquioxane prepared from trialkoxysilane and a vinylsilane coupling agent; the intermediate shell is a copolymer of an acrylic monomer and the vinylsilane coupling agent; the vinylsilane coupling agent accounts for 3-10wt% of the mass of the total monomer on the intermediatelayer; the component of the shell layer is a copolymer of a hydroxyl functional monomer and an acrylic monomer; and the hydroxyl functional monomer accounts for 10-50wt% of the amount of the total monomer. Due to the existence of the hydroxyl functional monomer, the composite emulsion has excellent mechanical property after curing, and has excellent properties such as high adhesive force of plastics.

The invention provides a styrene-acrylic emulsion for manufacturing artificial stone for solving the problems of lots of harmful VOCs (volatile organic compounds) existing in artificial stone, as well as high shrinkage percentage, low flame retardance, bad corrosion resistance, low hardness and the like of products, and provides a preparation method for the emulsion, and artificial stone prepared from the emulsion. The artificial stone is excellent in chemical corrosion resistance, pollution resistance, heat resistance and water resistance, and great in hardness.

The invention discloses a photo-thermal free radical polymerization preparation method of a vinyl polymer and an application of the polymer. The method uses a photo/thermal composite initiator to initiate polymerization of a vinyl monomer, firstly a photoinitiated polymerization reaction is performed, and a thermal polymerization reaction is performed after the thermal polymerization reaction temperature is achieved. The method for preparing the vinyl polymer provided by the invention can reduce energy consumption, reduce reaction time, and improve production efficiency, and the product has amore uniform structure, better performance, a lower gelation rate or even no gel and a higher conversion rate of the monomer; and the vinyl polymer prepared by the method can be used for coating and photocrosslinking products.

The invention discloses a synthetic method of a waterproof acrylate emulsion. The synthetic method comprises the following steps: 1) 2-8 parts by weight of an emulsifier and 50-70 parts by weight of water are placed in an emulsification kettle, 10-25 parts of an acrylic monomer are added for polymerization after the emulsifier is dissolved, and a pre-emulsion is obtained; 2) 0.2-1.0 part of the emulsifier and 8-10 parts of the water are placed into a reaction kettle and heated to 85-90 DEG C, 50-60 parts of the pre-emulsion, 0.2-1.0 part of an initiator and 2-5 parts of a silane coupling agent KBM-503 are added, the mixture reacts under a heat preservation condition for 1-2 h, then the temperature is reduced to 65-75 DEG C, reaction is performed under the heat preservation condition for 20-60 min, cooling is performed, the pH value of a reactant is regulated to 8-9, filtering is performed, and a product is obtained, wherein the emulsifier comprises 30%-50% by mass of DSB and the balance of the emulsifier OP-10. The emulsion has good stability and lower gel rate and only contains very few coagula.

The invention discloses external wall elastic emulsion with an antistatic effect and a method for preparing the external wall elastic emulsion. The external wall elastic emulsion comprises, by weight,90-120 parts of deionized water, 10-30 parts of iso-octyl acrylate, 60-80 parts of butyl acrylate, 20-35 parts of styrene, 5-15 parts of methyl methacrylate, 0.1-2 parts of acrylic acid, 0.1-1.5 parts of methacrylic acid, 0.1-1 part of acrylamide, 0-0.5 part of methacrylamide, 0-0.5 part of hydroxyethyl acrylate, 3-10 parts of acrylonitrile, 0.5-3 parts of acid anhydride functional monomers, 0.5-4 parts of diethanolamine, 0.1-3 parts of modified organophosphate high polymers, 1-8 parts of emulsifiers, 0.1-5 parts of initiators and 0.3-4.5 parts of ammonia water. The external wall elastic emulsion and the method have the advantages that the antistatic effect can be realized by the external wall elastic emulsion, the external wall elastic emulsion is excellent in stain resistance, and the excellent normal-temperature and low-temperature elasticity of the external wall elastic emulsion can be kept.

The invention discloses a preparing method for a polyester composition. An esterification reaction between aromatic dicarboxylic acid and aliphatic dihydric alcohol is firstly performed in the method;an antimony compound, an inorganic acid containing phosphorus, or an organic compound containing phosphorus and phosphoric acid alkali metal salt are added to the reaction system from the end of esterification reaction to the beginning of a polymerization reaction to begin the polymerization reaction; in the time period from the inherent viscosity of the polymerized reactant reaching 0.5dl/g to the end of the polymerization reaction, a manganese compound is added to the reaction system to the continue the polymerization reaction until the end of the polymerization reaction. The gel fraction of the polyester composition prepared through the method is under 5wt% in a N2/O2 gas mixture (oxygen concentration is 1 vol%) after thermal treatment of 300DEG C * 6hr and the polyester composition can be used for preparing thin films and fibers with little foreign material.

The invention discloses a preparation method of organic silicon modified acrylate bedplate glue. The bedplate glue is prepared from the following components in parts by weight: 200-380 parts of ionized water, 4-5 parts of anionic emulsifier, 120-160 parts of butyl acrylate, 80-120 parts of isooctyl acrylate, 20-30 parts of methyl methacrylate, 10-20 parts of styrene, 2-5 parts of acrylic acid, 2-5 parts of acetylated modified acrylic acid self-crosslinking monomer, 2-4 parts of vinyltriisopropoxysilane, 0.05-0.1 part of potassium persulphate, 0.4-0.6 part of sodium bicarbonate 0.5-1 part of a cohesion accelerator SA500, 0.1-0.2 part of an anantiseptic agent, 0.1-0.2 part of a water-based defoaming agent and 0.5-1 part of an associative thickener; and the pH value is adjusted to 7-8 with ammonia water. The bedplate glue can be applied to high-temperature and high-humidity resistant environments such as a flat screen machine, an elliptical machine and an octopus machine in machine printing. The product provided by the invention has higher moisture resistance and thermal stability and higher yellow resistance and high temperature resistance, and an emulsion has higher strength and heat resistance and has high viscosity but no reverse adhesion.