12results about How to "High carboxyl content" patented technology

The present application belongs to the field of medical polymer technology, and in particular, relates to a polyacid polymer hydrogel, and its preparation method and application. The polyacid polymer hydrogel involved in the present application mainly contains a polyacid polymer aqueous phase; the preparation method provided includes first dissolving a polycarboxylic acid polymer in an alkaline solution, then dripping a pH adjuster and stirring, and standing to obtain a polycarboxylic acid polymer hydrogel. Among them, after lowering the pH of the alkaline aqueous solution of the polycarboxylic acid polymer, the polycarboxylic acid chains are entangled during the standing process, and the interaction force between the polymer chains is enhanced to form a polycarboxylic acid polymer hydrogel. This type of hydrogel has a simple source of materials and an easy preparation method, which solves the technical problems that the preparation process of the existing polycarboxylic acid-containing polymer hydrogel is cumbersome, toxic reagents are required, and the product hydrogel lacks adhesion and self-healing.

The invention provides a concrete water reducing agent and a preparation method thereof, and belongs to the technical field of water reducing agents. Adding the modified chitin, 1-vinyl-3-butylimidazolium trifluoromethanesulfonate, a silane coupling agent with double bonds, methacrylic acid, trans-butenedioic acid and an initiator into dimethylformamide, heating and stirring for reaction, removing methylbenzene under reduced pressure, and performing alkali washing and alcohol washing to obtain the concrete water reducing agent. The modified chitin is prepared by modifying chitin modified by sodium sulfonate and acrylic acid with tannic acid. Modified chitin, 1-vinyl-3-butylimidazolium trifluoromethanesulfonate, a silane coupling agent with double bonds, methacrylic acid and trans-butenedioic acid are copolymerized to prepare the polycarboxylate superplasticizer, molecules of the polycarboxylate superplasticizer are of a comb-shaped structure, a main chain of the polycarboxylate superplasticizer is provided with a plurality of active groups with high polarity, and a side chain of the polycarboxylate superplasticizer is provided with hydrophilic active groups. The water-reducing agent has the characteristics of low doping amount, high water-reducing rate, high reinforcing effect, high plasticity retaining property and volume stability, and has wide application prospects.

The invention belongs to the field of preparation of oxidized starch, and relates to a method for preparing oxidized starch by a mechanochemical method. Hydroxyl of corn starch is oxidized by hydrogen peroxide to generate modified starch with high carboxyl content, so that the modified starch has wider application. The preparation thought of a full bio-based mechanical method is adopted, the obtained modified starch has good economical efficiency, environmental safety and natural degradability, and the problems that an oxidized starch preparation process in the current market is large in environmental pollution, wastes resources, is tedious in process and the like are solved. According to the invention, biomass is used as a reaction raw material, is renewable and degradable, and accords with the green chemistry concept.

The invention provides a preparation method of transparent nano-crystalline cellulose with high carboxyl content, and particularly relates to a method for preparing transparent nano-crystalline cellulose colloid with high carboxyl content by adopting sodium hydroxide to pretreat a raw material, then using a Fenton reagent, adding a TEMPO / NaBr / NaClO system and NaClO2 to jointly oxidize a natural cellulose raw material and then carrying out mechanical homogenization treatment. The operation method is simple, the operation process is safe, and the product yield is high. The oxidation degree of the natural cellulose raw material is increased, the carboxyl content of the oxidized product is improved, and the transparency of the product is improved, so that the application range is wider.

This invention relates to the field of carbon nanotube technology, specifically disclosing a high-viscosity carbon nanotube conductive paste and its preparation method. The raw materials for this high-viscosity carbon nanotube conductive paste include ultra-long single-walled carbon nanotubes, short-cut multi-walled carbon nanotubes, conductive carbon black, carboxyl-terminated hyperbranched polyester-polyethylene glycol block copolymer, polyacrylic acid, fluorinated silane coupling agent, γ-butyrolactone, and N-methylpyrrolidone. The high-viscosity carbon nanotube conductive paste provided by this invention achieves uniform dispersion, low volume resistivity, excellent anti-settling properties, and good coating processability of the carbon nanotube conductive paste under high solids content through the synergistic effect of the carboxyl-terminated hyperbranched polyester-polyethylene glycol block copolymer, the fluorinated silane coupling agent, and polyacrylic acid, combined with multi-stage grinding and high-pressure homogenization processes.

The invention relates to the technical field of preparation of layered composite films, and discloses an anti-aging sand water retention film material and a preparation method thereof. According to the anti-aging sand water retention film material, a protective layer, a base material layer and a saline-alkaline resistant layer are sequentially arranged from top to bottom, and the protective layer comprises linear low-density polyethylene, high-density polyethylene, an ethylene-vinyl acetate copolymer, metallocene polyethylene, carbon fibers and polyethylene grafted maleic anhydride. The base material layer comprises high-density polyethylene, an organic-inorganic hybrid composite material, a thermoplastic polyamide elastomer and polyethylene grafted glycidyl methacrylate, and the saline-alkaline resistant layer comprises aerogel filler and high-density polyethylene. The anti-aging sand water retention membrane material has good mechanical strength, puncture resistance, toughness, hydrophilic water retention and saline-alkaline aging resistance, is easy to recover and reduces white pollution.

The invention belongs to the field of textile auxiliaries, and discloses environment-friendly wool protection resin as well as a preparation method and application thereof. After wool is treated by the environment-friendly wool protection resin, the breaking strength retention rate of the wool is relatively high, no negative influence is caused on color fastness and hand feeling in the finishing process, and the environment-friendly wool protection resin has obvious advantages compared with commercially available competitive products.

This invention belongs to the field of high-efficiency concrete water-reducing agents, specifically relating to a composite polycarboxylate anti-mud water-reducing agent, its preparation method, and its application. The composite polycarboxylate anti-mud water-reducing agent comprises the following raw materials: 30-40 parts by weight of anti-mud polycarboxylate water-reducing agent and 1-3 parts by weight of anti-mud sacrificial agent. The anti-mud polycarboxylate water-reducing agent is polymerized from methyl allyl polyoxyethylene ether and unsaturated carboxylic acid under the initiator and chain transfer agent. The anti-mud sacrificial agent is obtained by adding 4-5 parts by weight of hydrogen peroxide to 20-30 parts by weight of papermaking black liquor. The anti-mud sacrificial agent effectively resists the interference of soil on the polycarboxylate water-reducing agent and is simple to prepare, environmentally friendly, and pollution-free. The composite polycarboxylate anti-mud water-reducing agent prepared by this invention has good anti-mud properties, exhibits good dispersibility in mud-containing concrete, and also has good slump retention properties.

The invention discloses an anti-aging polylactic acid composition as well as a preparation method and application thereof. The anti-aging polylactic acid composition comprises polylactic acid resin, a tin element and a phosphorus element, the mass ratio of the tin element in the anti-aging polylactic acid composition is less than or equal to 600ppm, the mass ratio of the phosphorus element in the anti-aging polylactic acid composition is less than or equal to 500ppm, and the mass ratio of the tin element to the phosphorus element is (0.3-5): 1; the weight-average molecular weight of the polylactic acid resin is 100000 to 200000, and the molecular weight distribution coefficient of the polylactic acid resin is 1.5 to 2.1. According to the anti-aging polylactic acid composition disclosed by the invention, by adding the phosphorus element and regulating and controlling the molecular chain length and distribution uniformity of the polylactic acid resin, the increase of the terminal carboxyl group content of the polylactic acid resin in a humid and hot environment is inhibited, so that the polylactic acid composition has excellent humid and hot resistance stability.

The invention belongs to the field of electrochemical biosensors, and discloses a preparation method of conductive ink for preparing a high-robustness glucose sensor, and the preparation method comprises three steps of color paste pre-dispersion, ink mixing and ink grinding. According to the method, carboxylated nanocellulose is introduced into conductive ink to serve as an ink auxiliary agent, so that the carboxyl content of the surface of a screen-printed electrode is remarkably increased; the prepared conductive ink provides a large number of stable enzyme immobilization sites in the modification process of glucose oxidase, the robustness and stability of a glucose sensor in the repeated and intermittent use process are remarkably improved, and the method is simple, efficient and easy to implement. The method is suitable for large-scale production of stable and reliable sweat glucose detection sensors, and has important medical application value.

The invention discloses an acetic acid modified aluminum oxide coated titanium dioxide adsorbent as well as a preparation method and application thereof, and belongs to the technical field of adsorbent preparation. The adsorbent is ball-flower-shaped and comprises titanium dioxide balls and flaky acetic acid modified aluminum oxide embedded into the surfaces of the titanium dioxide balls. The preparation method comprises the following steps: firstly, adding a titanium source, an aluminum source and a precipitator into water, obtaining a precursor by adopting a hydrothermal coprecipitation method, and then calcining and performing acetic acid dipping modification. The acetic acid modified aluminum oxide coated titanium dioxide adsorbent is prepared by utilizing hydrothermal coprecipitation and normal-temperature impregnation methods, and by utilizing the interaction of the acetic acid modified aluminum oxide coated titanium dioxide adsorbent and PCl3, not only can trace PCl3 be efficiently removed, but also the adsorbent can be repeatedly used after being desorbed, so that the consumption of the adsorbent is reduced, and the cost is saved. The invention provides a novel method for removing trace PC13.

The invention discloses a method for preparing cellulose nanocrystals under the assistance of a pulsed electric field. The method comprises the following steps: treating cellulose powder through a pulsed electric field, controlling the intensity of the electric field to be 10-30kV / cm, carrying out suction filtration and drying after treatment, adding an ammonium persulfate solution into the obtained solid for oxidative degradation, and centrifuging to prepare the cellulose nanocrystal. The method is green and low in toxicity, and the yield of the cellulose nanocrystal is remarkably improved under the action of the pulsed electric field. Besides, the prepared cellulose nanocrystal has higher dispersion stability, excellent specific surface area, no harmful substance residue and higher carboxyl content, more chemical ways are provided for further modification of the nanocellulose, and a new method is provided for pretreatment of preparation of the cellulose nanocrystal.