12 results about "Polymalic acid" patented technology

The invention discloses a method for gene modification of aureobasidium pullulans, which belongs to the technical field of gene engineering, and comprises the following steps: determining a malic acid synthase gene, obtaining a malic acid synthase gene segment, searching a gene sequence of the malic acid synthase in the disclosed aureobasidium pullulans as a template on NCBI (National Center of Biotechnology Information), and carrying out gene modification on the malic acid synthase gene segment to obtain a malic acid synthase gene segment; the method comprises the following steps: respectively designing an upstream primer and a downstream primer, taking extracted genome DNA of aureobasidium pullulans M1 as a template, respectively carrying out PCR amplification and recombinant plasmid pUC57-PMA-ms construction and linearization treatment on the upstream primer and the downstream primer, and introducing the plasmid into the aureobasidium pullulans M1 to obtain an aureobasidium pullulans recombinant strain; according to the method, the polymalic acid synthetase gene (PMA-ms) on an aureobasidium pullulans genome is knocked out from aureobasidium pullulans, the yield of pullulan in the obtained recombinant plasmid M1-2 is about 39.11 g / L, and compared with an original strain M1, the yield of M1-2 is increased by 9.79 g / L, and the practical application prospect of the method is improved.

The invention relates to the technical field of coatings, and discloses a functional coating based on bio-based waterborne polyurethane and a preparation method thereof.The functional coating is formed by taking bio-based waterborne polyurethane emulsion as a film forming matter and taking ammonium polyphosphate and the like as auxiliary materials through mixing, an isocyanate monomer is used as a hard segment and is subjected to cross-linking polymerization with a chain extender and a molybdenum disulfide modified material under the action of a catalyst, polyhydroxy polymalic acid is used as a biomass raw material, has water solubility and conforms to the environment-friendly concept, and polyhydroxy polymalic acid is used as a soft segment, so that the molecular chain density of the prepared polyurethane is greatly increased, and the mechanical property of the polyurethane is improved. The molybdenum disulfide modified material is added into polyurethane, so that a coating formed by curing the coating has higher density, the mechanical properties such as hardness of the coating are improved, the molybdenum disulfide modified material can participate in chain extension of polyurethane, organic combination of nano molybdenum disulfide and polyurethane is realized, and the wear resistance and mechanical strength of the coating are effectively improved.

The invention discloses a modified aureobasidium pullulans strain based on reduction of malic acid pathway consumption and application of the modified aureobasidium pullulans strain. Gene for coding NADPH dependent malic enzyme and phosphoenolpyruvate carboxykinase in an aureobasidium pullulans genome is directionally knocked out. The transformation blocks a key consumption branch for synthesis and accumulation of the cytoplasmic malic acid, and effectively guides a central carbon metabolic flow to be more efficiently guided to a target product. Experimental results show that the polymalic acid yield and the saccharic acid conversion rate of the double-knockout engineering strain D3N5-delta3617 / deltapepck in fermentation are remarkably improved compared with those of an original strain, and the biomass is also increased. The invention provides a high-performance strain with important application value for industrial efficient fermentation production of polymalic acid.

The application discloses synergistically modified ethyne carbon black by poly malic acid and KH550, a preparation method and application thereof, and the method comprises the following steps: blending poly malic acid, gamma-aminopropyl triethoxysilane and ethyne carbon black in a mass ratio of (0.5-5):(1-10):100, and then performing reaction to obtain ethyne carbon black synergistically modified by poly malic acid and gamma-aminopropyl triethoxysilane. The ethyne carbon black is synergistically modified by poly malic acid and gamma-aminopropyl triethoxysilane (KH550), an esterification reaction occurs between the carboxyl in the poly malic acid molecule and the surface hydroxyl of the ethyne carbon black, meanwhile, a hydroxylamino reaction occurs between the amino group of the KH550 and the hydroxyl, and an amide bond bridge is formed between the poly malic acid and the KH550, thereby realizing ternary synergistic covalent modification. The structure effectively improves the dispersion stability of the ethyne carbon black, the chain-like or grape-like high specific surface area structure of the ethyne carbon black can be fully utilized, the ethyne carbon black is more uniformly dispersed in a polymer matrix, and the interface is more closely combined.

Disclosed in the present invention are a cross-linked polyamide hydrogel material and a preparation method therefor. The hydrogel is obtained by means of a cross-linking reaction between a water-soluble polyamide and a cross-linking agent. The water-soluble polyamide comprises poly(malic acid-spermidine), poly(malic acid-spermine), poly(succinic acid-spermidine), or poly(succinic acid-spermine). The cross-linking agent is an endogenous dibasic acid. The cross-linking reaction means that after being activated by a catalyst, a carboxyl group on the endogenous dibasic acid undergoes a two-step activation cross-linking reaction with an imine group on the backbone of the polyamide to obtain the hydrogel. The present invention prepares the hydrogel by means of a two-step activation cross-linking technique. By means of the cross-linking technique, the amounts of the catalyst and the cross-linking agent can be reduced, and hydrogels having different properties can also be prepared by controlling the type of the cross-linking agent and cross-linking conditions, thereby improving the cross-linking reaction efficiency and achieving the control of the degradation rate of the hydrogel and the release rate of an active monomer, exhibiting broad application prospects.

The invention belongs to the technical field of water treatment, and particularly relates to a phosphorus-free and zinc-free corrosion and scale inhibitor for a soft water closed circulating cooling water system, which comprises the following components in parts by weight: 10-25 parts of a scale inhibition dispersant, 25-35 parts of a corrosion inhibitor and 40-55 parts of an auxiliary agent, wherein the scale inhibition dispersant is one or more of an acrylic acid-acrylate-organic sulfonate terpolymer, hydrolytic polymaleic acid, sodium gluconate and polyepoxysuccinic acid; and the corrosion inhibitor is azole QD-504, amphoteric imidazoline, sodium benzoate, polyepoxysuccinate and the like. The scale inhibitor has good corrosion inhibition performance on stainless steel, carbon steel, navy copper and other materials, and has a good dispersion effect on dust, microbial slime and the like entering a circulating cooling water system. When the corrosion and scale inhibitor is put into use, phosphate scale cannot be formed in circulating water, wastewater discharged from the circulating water cannot cause phosphorus-containing eutrophication and zinc pollution to the environment, and the corrosion and scale inhibitor belongs to an environment-friendly product.

The application relates to the technical field of polymer synthesis, in particular to an initiation / catalyst and a preparation method and application thereof, polylactic acid-poly(malic acid) and a preparation method and application thereof. The application provides an initiation / catalyst, and the preparation raw materials include 4-hydroxymethyl benzoic acid and 1,8-diazabicyclo[5.4.0]undec-7-ene. The initiation / catalyst has the advantage of weakened biological toxicity in biological medicine compared with a metal catalyst which is traditionally adopted.

The invention discloses a cross-linked polyamide hydrogel material and a preparation method thereof. The hydrogel is obtained by carrying out a cross-linking reaction on water-soluble polyamide and a cross-linking agent; the water-soluble polyamide comprises poly (malic acid-spermidine), poly (malic acid-spermine), poly (succinic acid-spermidine) or poly (succinic acid-spermine), and the cross-linking agent is endogenous binary acid; the cross-linking reaction refers to that carboxyl on the endogenous binary acid is activated by a catalyst and then is subjected to two-step activation cross-linking reaction with imino on a polyamide main chain to obtain the hydrogel. The hydrogel is prepared by adopting a two-step activation cross-linking technology, the cross-linking technology can reduce the dosage of a catalyst and a cross-linking agent, the hydrogel with different properties can be prepared by controlling the variety of the cross-linking agent and the cross-linking condition, the cross-linking reaction efficiency is improved, the degradation rate of the hydrogel and the release rate of the active monomer are controlled, and the cross-linking efficiency is improved. And the method has a very good application prospect.

The utility model discloses saccharomycetes fermentation optimization equipment in polymalic acid production, and relates to the technical field of polymalic acid production, and the saccharomycetes fermentation optimization equipment comprises a fermentation box, the inner side of the fermentation box is provided with a corrosion-resistant layer, the inner wall of the corrosion-resistant layer is provided with a heating rod, the bottom of the fermentation box is provided with a discharge valve, and the bottom end of the discharge valve is provided with a connector; a connecting pipe is movably installed on the outer side of the connector through threads, and an assembling cover is installed at the bottom end of the connecting pipe. The bottom end of the discharge valve is fixedly connected with the connector, the outer side of the connector is connected with the connecting pipe through threads, the bottom end of the connecting pipe is fixedly connected with the assembling cover, the outer side of the assembling cover is connected with the assembling shell through threads, the assembling shell supports the filter screen on the inner side, and stability of the filter screen is guaranteed; the bottom of the filter screen is fixedly connected with the output port, the output port discharges the yeast liquid, and in the discharging process, the filter screen filters impurities in the yeast liquid, so that the quality of the yeast liquid is improved.

The invention discloses acetylene carbon black synergistically modified by polymalic acid and KH550 as well as a preparation method and application of the acetylene carbon black, and the method comprises the following steps: blending polymalic acid, gamma-aminopropyltriethoxysilane and acetylene carbon black in a mass ratio of (0.5-5): (1-10): 100, and reacting to obtain the acetylene carbon black synergistically modified by polymalic acid and gamma-aminopropyltriethoxysilane. Polymalic acid and gamma-aminopropyltriethoxysilane (KH550) are adopted for synergistic modification of acetylene carbon black, carboxyl in polymalic acid molecules and hydroxyl on the surface of acetylene carbon black are subjected to an esterification reaction, meanwhile, amino of KH550 and hydroxyl are subjected to a hydroxyamination reaction, amido bond bridging is formed between the polymalic acid and KH550, and the modified acetylene carbon black is obtained. The ternary synergistic covalent modification is realized. The structure effectively improves the dispersion stability of the acetylene carbon black, and the chain-shaped or grape-shaped high specific surface area structure of the acetylene carbon black is fully utilized, so that the acetylene carbon black is more uniformly dispersed in a polymer matrix, and the interface bonding is tighter.

The invention relates to the technical field of building materials and discloses a Portland cement-based building concrete and a manufacturing process thereof. The building concrete comprises the following raw materials: sand, crushed stone, fly ash, ordinary Portland cement, functionalized fibers, a composite additive, and water. The functionalized fibers are prepared by introducing sulfonic acid groups and amide groups into sepiolite fibers. The composite additive is an additive prepared by sequentially reacting polymalic acid with epoxy soybean oil and 2,3-epoxypropyltrimethylammonium chloride. The present invention utilizes the advantages of the functionalized fibers and the composite additive to ensure that the prepared building concrete has good anti-cracking performance, compressive strength, water retention performance, and mud resistance, thereby improving the stability and durability of the building concrete and having wide engineering application value.

An automatic dishwashing detergent formulation is provided including a builder, wherein the builder comprises at least one of a carbonate, a silicate and an organophosphonate; a nonionic surfactant; and a poly(malic ester) polymer comprising > 60 mol% of structural units of malic acid.