11results about How to "Molecular weight controllable" patented technology

The invention provides a preparation method of ultralow-viscosity vinyl methoxy-terminated silicone oil, which is mainly applied to a structure control agent in the field of silicone rubber.The preparation method comprises the steps that a polydimethylsiloxane linear body serves as a raw material, dimethyl vinyl methoxy silane serves as an end-capping reagent, a base catalyst is added, a polymerization reaction is conducted till the viscosity is stable, and the ultralow-viscosity vinyl methoxy-terminated silicone oil is obtained. And adding phosphoric acid gel for neutralization, carrying out gradient heating to 90 DEG C, and carrying out devolatilization under a vacuum condition to obtain the methoxy hydroxyl-terminated silicone oil. The technological process is simple and easy to operate, and the product is uniform in molecular weight distribution and high in flash point, has the advantages of improving the processability and the mechanical property as a structure control agent, and can improve the molecular crosslinking density and improve the strength of a silica gel product in the product vulcanization technological process.

This invention discloses a water-soluble anti-collapse agent, its preparation method, and a water-based slurry. The raw materials for the water-soluble anti-collapse agent include melamine, formaldehyde aqueous solution, polyol, epichlorohydrin, water, initiator, organophosphonate, and comonomer. The preparation method includes the following steps: mixing melamine and formaldehyde aqueous solution, adjusting the pH, and then reacting; introducing polyol into the reaction system to continue the reaction; then introducing organophosphonate solution into the reaction system, followed by epichlorohydrin to continue the reaction; finally introducing comonomer and initiator to continue the reaction, and then drying and optionally crushing to obtain the water-soluble anti-collapse agent. A water-based slurry containing the above-mentioned water-soluble anti-collapse agent is also provided. The anti-collapse agent provided by this invention has a filtration loss reduction rate of more than 70% against complex salts and a shale secondary rolling recovery rate of more than 80%. It has good salt resistance, temperature resistance, wall consolidation, and filtration loss reduction performance, and also has the advantages of being environmentally friendly, having low fluorescence, and good water solubility.

The application provides a kind of biomimetic peptide anti-icing and antifreezing agent and its preparation method and application, belong to the field of biological polymer synthesis;The biomimetic peptide anti-icing and antifreezing agent described in the application uses hydroxyl side chain as hydrophilic side chain, alkyl chain as hydrophobic side chain, and is synthesized by solid phase subunit synthesis method according to the designed structure to obtain biomimetic peptide anti-icing and antifreezing agent containing different hydrophilic and hydrophobic sequences;The biomimetic peptide anti-icing and antifreezing agent can form hydrogen bond interaction with the surface of ice crystal to inhibit water molecule movement, and the hydrophobic alkyl group can affect and prevent water molecules from gathering through hydrophobic interaction, thereby effectively regulating ice crystal growth.

The invention discloses an epoxy resin composition containing a phosphorus-containing flame-retardant curing agent as well as a preparation method and application of the epoxy resin composition, and belongs to the technical field of preparation of flame-retardant epoxy resin compositions. The epoxy resin composition comprises the following components in parts by weight: 80-100 parts of an epoxy resin matrix, 10-30 parts of a phosphorus-containing flame-retardant curing agent, 6-60 parts of a curing agent, 0.1-0.3 part of an accelerant, 10-30 parts of a synergistic flame retardant, 40-60 parts of filler and the like. The phosphorus-containing flame-retardant curing agent is prepared from phenyl phosphoryl dichloride and a bisphenol compound through a polymerization reaction. The phosphorus-containing flame-retardant curing agent with phenolic hydroxyl reaction active groups is prepared by using low-cost phenylphosphoryl dichloride as a raw material and is matched with an existing flame-retardant system, so that the contradiction between the flame-retardant property and the physical property (mainly Tg) of an epoxy resin material is solved; and the flame retardant grade of V-0 and the higher glass transition temperature can be achieved when the addition amount of the flame retardant is lower.

This invention discloses a novel cross-linked polymeric demulsifier and its preparation method. Specifically, it uses a polyoxyethylene / polyoxypropylene block polyether demulsifier as a base, which undergoes esterification of terminal hydroxyl groups, followed by a Michael addition reaction with ethylene amine to obtain the cross-linked polymeric demulsifier. This novel cross-linked polymeric demulsifier exhibits low organochlorine residue, a simple production process, mild reaction conditions, controllable molecular weight, and uniform molecular weight distribution. In application, it offers significant advantages such as high demulsification efficiency, rapid demulsification speed, low dosage, and low demulsification temperature, as well as broad applicability to various crude oil emulsions.

This invention relates to the field of polymer technology, and discloses a catalyst composition, polylactide, its preparation method, and its applications. The catalyst composition of this invention contains a zinc complex and a hydroxyl-containing compound. When the catalyst composition provided by this invention is used for the ring-opening polymerization of lactide to prepare polylactide, it not only exhibits high catalytic activity, but also produces a polymer with a high molecular weight, adjustable molecular weight, and a narrow molecular weight distribution.

This invention relates to a novel organochlorine-free crosslinked polymeric demulsifier and its preparation method. Specifically, a linear polyether demulsifier is reacted with a chain extender, homogenizing anhydride, to obtain an esterified chain-extended product of the linear polyether demulsifier. This esterified chain-extended product is then reacted with a crosslinking agent, a diol, under specific temperature and catalytic conditions to obtain the novel organochlorine-free crosslinked polymeric demulsifier. This novel organochlorine-free crosslinked polymeric demulsifier is effective in demulsifying and dehydrating crude oil emulsions that are severely emulsified, difficult to separate oil and water, and challenging to demulsify due to high concentrations of polymers, surfactants, alkalis, and other active substances remaining in the produced fluids of tertiary oil recovery. It also meets the key quality control indicators specified by oilfields when purchasing oilfield chemicals.

The application relates to a preparation method of an ultra-high-temperature fluid loss additive for well cementing, and belongs to the technical field of oilfield chemicals. After surface modification of palygorskite by a silane coupling agent, the surface polymerization sites of the palygorskite are obtained, so as to participate in a polymerization reaction. N,N-dimethyl acrylamide and other non-ionic water-soluble monomers, 2-acrylamide-2-methylpropanesulfonic acid, itaconic acid, sodium styrene sulfonate and other anionic water-soluble monomers, and vinyl pyrrolidone, sodium p-styrene sulfonate and other rigid monomers are used as polymerization raw materials to synthesize polymer grafted palygorskite. The fluid loss additive has excellent temperature resistance and salt resistance, has excellent fluid loss performance in a high-temperature and ultra-high-temperature environment, the fluid loss amount is less than 50 mL at 240 DEG C, has no obvious influence on other basic performances of cement slurry, can effectively improve the suspension stability of the cement slurry at high temperature, and is suitable for being used as a fluid loss additive for cement slurry under harsh conditions.

The invention relates to the technical field of polymer chemical synthesis, in particular to a preparation method of methoxy polyethylene glycol methacrylate or methoxy polyethylene glycol acrylate. A two-step synthesis method is adopted and comprises the following steps: firstly, carrying out ethoxylation reaction on methacrylic acid or acrylic acid and ethylene oxide in the presence of a catalyst to generate a methacrylic acid polyethylene glycol ester intermediate or an acrylic acid polyethylene glycol ester intermediate; and carrying out end capping on the intermediate, alkali and halomethane through a Williamson ether synthesis reaction to obtain high-purity methoxy polyethylene glycol methacrylate or methoxy polyethylene glycol acrylate. The invention overcomes the problems of high reaction temperature, low conversion rate, insufficient product purity and easy polymerization of methacrylate or acrylate in the traditional transesterification method, and overcomes the defects of long synthetic route steps and high cost in the prior art. The method has the advantages of mild process conditions, controllable molecular weight and high product purity, and is suitable for the fields of biomedical materials, cosmetics, polymer emulsifiers and the like.

The invention provides bisphenol A type low-molecular-weight polycarbonate polyether polyol and a production process thereof, and relates to the technical field of chemistry and chemical engineering. The production process is carried out in an integrated tubular reaction device, and comprises the following steps: premixing the epoxy compound, CO2, bisphenol A and a catalyst, and feeding the mixture into a reaction pipeline at one time to carry out polymerization reaction. In the polymerization reaction process, slow heating control and gas pressurization compensation are carried out, so that the molecular weight polydispersity index PDI of the bisphenol A type low-molecular-weight polycarbonate polyether polyol does not exceed 1.5, the carbonic ester chain link proportion FCO2 is greater than 55%, and in the Lab color system, the b value does not exceed 0.1. Through the regulation and control process, the problem of yellowing of the product generated in the one-step preparation process of the bisphenol A type low-molecular-weight polycarbonate polyether polyol can be solved, and the production efficiency is high. And the prepared product is narrow in molecular weight distribution, does not generate implosion, has no amplification effect, and is suitable for industrial large-scale production.

This invention discloses a Co-CFA-1-based butadiene polymerization catalyst and its preparation method. The butadiene polymerization catalyst comprises Co-CFA-1, a co-catalyst, and toluene solvent. The Co-CFA-1 is prepared by heating a dispersion of CFA-1 and cobalt acetate tetrahydrate in NMF at 55–65°C for 18–30 hours, followed by filtration, washing, and vacuum drying to obtain Co-CFA-1. The co-catalyst is composed of alkylaluminum and methylaluminoxane, wherein the alkylaluminum is selected from at least one of diethylaluminum chloride, triisobutylaluminum, and diethylaluminum chloride. This invention provides the application of the Co-CFA-1-based butadiene polymerization catalyst in the preparation of cis-polybutadiene, which can produce high-quality polybutadiene rubber products with high cis-structure content, controllable molecular weight, and narrow molecular weight distribution, and the product yield is high.