94 results about "Dimethylaniline N-oxide" patented technology

The invention relates to the technical field of composite materials, in particular to a nano-montmorillonite reinforced unsaturated polyester resin based composite material and a preparation method thereof. Comprising the following raw materials in parts by weight: 60-85 parts of orthophthalic unsaturated polyester resin, 3-15 parts of nano montmorillonite, 1-5 parts of a polyfunctional group intercalator, 1-4 parts of an initiator, 0.5-2 parts of dimethylaniline and 0.5-3 parts of gamma-aminopropyltriethoxysilane. The polyfunctional intercalator interacts with interlayer ions and surface groups of the nano-montmorillonite through multiple functional groups of the polyfunctional intercalator, and is effectively inserted into the interlayer of the nano-montmorillonite, so that the interlayer spacing is obviously increased, and favorable conditions are provided for subsequent insertion and compounding of resin; the functional groups not only can chemically react with active groups of unsaturated polyester resin to form stronger chemical bonding, but also can enhance the interface bonding force between two phases through physical entanglement, so that the overall performance of the composite material is remarkably improved.

The invention relates to a method and a system for synthesizing N-methylaniline and co-producing N, N-dimethylaniline by a gas phase method, and belongs to the technical field of chemical engineering. The system comprises a raw material gasification unit, a reaction unit, a separation and rectification unit and a hydrogen recovery unit which are connected through pipelines. The method comprises the following steps of: firstly, mainly synthesizing N-methylaniline from raw materials aniline and part of methanol in a first-methylaniline reactor, then partially or completely feeding first-methylaniline reaction gas into a second-methylaniline reactor, adding methanol steam, and further reacting to generate N, N-dimethylaniline. And after the product gas is subjected to heat exchange energy recovery, a liquid phase and a gas phase respectively enter the separation and rectification unit and the hydrogen recovery unit. The purification of N-methylaniline and N, N-dimethylaniline and the recovery of byproduct hydrogen are realized. The yield of N, N-dimethylaniline (in terms of aniline) can be adjusted in a range of 5-30% by adjusting reaction conditions and a feeding ratio.

The invention provides a preparation method of 4-fluoro-3, 5-dimethylphenylhydrazine hydrochloride, which comprises the following steps: salifying 4-fluoro-3, 5-dimethylaniline serving as a substrate with concentrated hydrochloric acid, reacting with sodium nitrite to prepare a diazo solution, reducing the diazo solution into corresponding phenylhydrazine by using alkaline sodium sulfite as a reducing agent system, and reacting the 4-fluoro-3, 5-dimethylphenylhydrazine hydrochloride with the diazo solution to prepare the 4-fluoro-3, 5-dimethylphenylhydrazine hydrochloride. And acidizing the 2, 5-dimethyl phenylhydrazine to obtain corresponding phenylhydrazine hydrochloride. According to the preparation method, sodium sulfite which is low in cost and easy to obtain is used as a reducing agent, the defects that metal residues are high, the environment is prone to being polluted and the raw material cost is high due to the fact that a metal reducing agent is adopted when phenylhydrazine hydrochloride is prepared in the prior art are overcome, the reaction is completed in a water phase, no organic solvent is adopted, and the concept of green chemistry is met; and the problems of complicated post-treatment and easy pollution caused by the adoption of an organic solvent can be effectively avoided.

The invention belongs to the technical field of antitumor drugs, and particularly discloses a preparation method and application of a compound for near-infrared fluorescence imaging and photothermal-photodynamic synergistic treatment. The compound for near-infrared fluorescence imaging and photothermal-photodynamic synergistic treatment is shown in the following structural formula: # imgabs0, the molecular skeleton of the compound contains a triphenylamine unit and an N, N-dimethylaniline fragment, intramolecular rotation limitation and intramolecular vibration limitation can be generated, and obvious aggregation-induced emission (AIE) performance is shown. The function-integrated phototherapy agent has high active oxygen generation efficiency, photothermal conversion efficiency and near-infrared fluorescence quantum yield, and is beneficial to obtaining ideal photothermal-photodynamic therapy effect for deep tumors. The phototherapy agent is novel in structure, the preparation method is easy in raw material obtaining, the synthesis condition is mild, the preparation method is simple, purification is convenient and fast, implementation is easy, and the phototherapy agent has great application prospects.

The invention provides an inorganic silicon crystal-based nano inert material enhanced coating and a preparation process thereof, the coating comprises the following raw materials in parts by weight: 25-35 parts of nano silicon dioxide, 20-30 parts of trimethylolpropane, 30-40 parts of toluene diisocynate, 20-30 parts of phosphate, 10-20 parts of glass micro powder, 25-35 parts of vinyl polyester resin, 5-10 parts of N, N-dimethylformamide, 5-10 parts of a curing agent, 1-3 parts of a defoaming agent, 1-3 parts of a defoaming agent, and 1-3 parts of a defoaming agent. The coating is prepared from the following components in parts by weight: 10-20 parts of N, N-dimethylaniline, 5-15 parts of a flatting agent, 5-10 parts of a defoaming agent, 5-10 parts of a silane coupling agent, 5-15 parts of talcum powder and 10-20 parts of filler. A coating layer formed by the coating has good heat resistance, chemical stability, corrosion resistance, flame retardance, impermeability, flexibility and impact resistance.

The invention discloses a method for extracting and separating N-methylaniline and N, N-dimethylaniline, and relates to the technical field of organic compound separation.The method comprises the steps that a reaction product of aniline and methyl alcohol is taken and fed into an adsorption refiner to be adsorbed, and a mixture A is obtained; feeding the mixture A into a light component removal tower for light component removal, collecting at the top of the light component removal tower to obtain light components, feeding the light component removal tower into a heavy component removal tower for heavy component removal, and collecting at the top of the heavy component removal tower to obtain a mixture B; taking the mixture B, feeding from the middle part of an extractive distillation tower, taking an extracting agent, feeding from the upper part of the extractive distillation tower, and performing extractive distillation; collecting the N, N-dimethylaniline at the top of the extractive distillation tower to obtain N, N-dimethylaniline, and collecting the N, N-dimethylaniline at the bottom of the extractive distillation tower to obtain an N-methylaniline mixed solution; feeding the N-methylaniline mixed solution into a desorption tower for desorption; collecting at the top of the desorption tower to obtain N-methylaniline, and collecting at the bottom of the desorption tower to obtain the extracting agent.

The present invention relates to an N-alkylation catalyst, a preparation method therefor and a use thereof. The catalyst comprises a molecular sieve, an oxide binder and a modification component, the modification component being loaded on the molecular sieve and the oxide binder, the modification component comprising Cu and P, and the medium-strong acid content of the catalyst accounting for 35% or more of the total acid content. By means of controlling the order of addition of raw materials in a catalyst preparation process, and selecting Cu and P for synergistic modification, an N-alkylation catalyst having high activity, high stability, extended service life, and good recycling performance can be obtained. The catalyst is used to produce N,N-dimethylaniline, and can reduce side reactions, enable an N-alkylation reaction to operate stably for a long period, and expand a workable reaction temperature range, facilitating continuous industrial production.

The invention relates to the technical field of concrete materials, and discloses modified epoxy resin and a preparation method thereof, a composition for an epoxy resin grouting material, the epoxy resin grouting material and a preparation method and application of the epoxy resin grouting material. The method for preparing the modified epoxy resin comprises the following steps: heating a polyhydroxy compound and epoxy resin at 80-100 DEG C in a nitrogen atmosphere in the presence of a catalyst to obtain the modified epoxy resin, the molar ratio of the polyhydroxy compound to the epoxy resin to the catalyst is 1: (1-2): (0.05-0.1); the epoxy resin is bisphenol A epoxy resin; the catalyst is selected from any one of sodium hydroxide, potassium carbonate and dimethylaniline; the multi-hydroxyl compound is selected from at least one of glycerol, ethylene glycol, propylene glycol, glucose and butanediol. The epoxy resin grouting material provided by the invention has more excellent toughness and lower viscosity, and has good bonding strength and bonding durability with a concrete matrix.

The invention relates to the field of viscosity detection, and provides a fluorescent probe for detecting the viscosity of mask essence as well as a preparation method and application of the fluorescent probe. 4, 4 '-(iminomethylene) bis (N, N-dimethylaniline) which is slightly soluble in water reacts with acid to form auramine hydrochloride, the water solubility of the auramine hydrochloride fluorescent probe is greatly enhanced, the probe in a water phase is converted into heat (non-radiation decay) due to twisted intramolecular charge transfer and excited state energy caused by benzene ring rotation, and fluorescence quenching is shown; when the viscosity of the solvent is increased, rotation of the benzene ring is blocked, excited state energy cannot be converted into heat and is dissipated in a radiation attenuation mode, fluorescence is enhanced, and viscosity detection of the mask essence with the main component being water is achieved based on the principle. According to the present invention, the method has characteristics of simple synthesis, stable property, no interference of solvent polarity during detection, long-term storage and long-term use, rapid and high-specificity viscosity response ability, and quantitative analysis of viscosity.

The application discloses a synthesis method of 2,3,3',4'-biphenyl tetracarboxylic dianhydride, characterized in that 2,3-dimethylaniline is used as a starting raw material, 2,3-dimethylaniline diazonium salt is prepared through a diazotization reaction, then 2,3,3',4'-tetramethyl biphenyl is prepared through a coupling reaction of the 2,3-dimethylaniline diazonium salt and o-xylene under the catalysis of cuprous chloride, and finally 2,3,3',4'-biphenyl tetracarboxylic dianhydride is prepared through an oxidation reaction and dehydration to form anhydride. The coupling reaction in the synthesis method has good selectivity, 3,3,4',4'-tetramethyl biphenyl which is difficult to separate is not generated, high-purity a-BPDA can be finally obtained, and the coupling reaction in the synthesis method only needs to use low-cost cuprous chloride as a catalyst, so that the production cost is greatly reduced compared to a high-cost catalytic system in the prior art, and the synthesis method is more suitable for industrial mass production.

This invention relates to the field of polyaniline derivative preparation technology, and more particularly to a green preparation method for poly(2,3-dimethylaniline). The green preparation method provided by this invention includes mixing a reaction mother liquor for preparing poly(2,3-dimethylaniline), a nitric acid solution, and 2,3-dimethylaniline, and then adding Fe... 3+ The catalyst is subjected to a first heat treatment, hydrogen peroxide is added, and a second heat treatment is performed to obtain a first-use reaction mother liquor and a filter cake. The filter cake is post-treated to obtain the poly-2,3-dimethylaniline. The first-use reaction mother liquor is recycled according to the above process. During the above recycling process, when the COD content in the reaction mother liquor obtained after recycling is greater than 29000 mg / L, the molar ratio of H2O2 to 2,3-dimethylaniline in hydrogen peroxide is increased based on the molar ratio of H2O2 to 2,3-dimethylaniline in hydrogen peroxide during the first recycling process. The preparation method has high yield and is environmentally friendly.

The invention discloses a method for synthesizing 2-aminopyridine, comprising using polystyrene resin beads as a carrier, a mixed solvent consisting of 1,2-dichloroethane and anhydrous ethanol as a porogen, adding the polystyrene resin beads and the mixed solvent to a flask for swelling; adding N,N-dimethylaniline to the flask, and performing a stirring reflux reaction; repeatedly washing the mixed solution in the flask with anhydrous ethanol and filtering it with suction, and finally vacuum drying it at room temperature. The method for synthesizing 2-aminopyridine utilizes polymer resin beads as a carrier, grafts a preferred highly active phase transfer catalyst molecule - N,N-dimethylaniline, and synthesizes a solid-supported phase transfer catalyst to achieve efficient recycling and regeneration of the phase transfer catalyst, and ensures the yield of the pyridine amination product by the solid-supported phase transfer catalyst, which is conducive to ensuring the efficient resource utilization of basic nitrogen heterocyclic compounds in coal tar.

This invention belongs to the field of coating technology and relates to a high-temperature resistant CHPO curable putty and its preparation method, which comprises the following components: unsaturated polyester resin, styrene, cobalt isooctanoate, dimethylaniline, high-temperature resistant composite dispersant, hydrogenated castor oil, silica, rutile titanium dioxide, talc, and curing agent.

This invention belongs to the field of stone adhesive technology, specifically relating to a transparent stone splicing adhesive and its preparation method. The adhesive comprises a resin component and a curing component. The resin component includes maleic anhydride, phthalic anhydride, diol, catalyst, polymerization inhibitor, and crosslinking monomers, etc., and the diol includes at least 1,2-propanediol. The curing component includes an accelerator composed of dimethylaniline and zinc adipate, and a benzoyl peroxide initiator. The adhesive of this invention is colorless and transparent after curing, exhibits excellent resistance to yellowing, is easy to apply, and after curing with fillers, possesses excellent shear strength, water shear strength, and impact resistance. It can be widely used in high-end stone splicing, repair, and craft bonding.

The invention discloses a method for preparing an unsaturated nitrile, an N-15 labeled unsaturated nitrile and an N-15 labeled rilpivirine, using an N-15 ammonium salt or a common ammonium salt as a nitrogen source, and directly oxidizing to obtain an unsaturated nitrile or an N-15 labeled unsaturated nitrile in the presence of an oxidant; 2,6-dimethylaniline is synthesized using the synthesis method of the unsaturated nitrile, and starting from 2,6-dimethylaniline, N-15 labeled rilpivirine is synthesized using a five-step reaction. The present invention can achieve the synthesis of N-15 labeled unsaturated nitrile and N-15 labeled rilpivirine, and the raw materials used by the method are all simple and easy to obtain, and can be synthesized in a public commercial channel or according to the synthetic method reported in the literature, and the method is simple to operate, has a short reaction time, is easy to post-process, and is insensitive to water and air.

The present invention discloses a low exothermic antibacterial and anti-inflammatory injectable bone cement, its preparation method and uses. The preparation method includes the following steps: performing double bond modification on hydroxyapatite powder; grafting the double bond-modified hydroxyapatite with sulfobetaine by means of free radical polymerization to obtain betaine-modified hydroxyapatite; using a polymethyl methacrylate prepolymer solution as the liquid phase, and using the betaine-modified hydroxyapatite and benzoyl peroxide mixed in a certain proportion as the solid phase, and after adding an appropriate amount of N,N-dimethylaniline, fully stirring until uniformly mixed, and heating and curing to obtain the low exothermic antibacterial and anti-inflammatory injectable bone cement. The low exothermic antibacterial and anti-inflammatory injectable bone cement prepared by the present invention inhibits the damage to tissues and cells caused by the release of a large amount of heat, and at the same time, the betaine molecules play an antibacterial and anti-inflammatory role. The manufacturing process of the present invention is simple and has good practicability.

The invention discloses a catalyst for preparing N-(1-ethyl propyl)-3, 4-dimethylaniline through continuous catalytic hydrogenation and a preparation method and application thereof, the catalyst comprises a carrier, and an active component platinum and an auxiliary component which are loaded on the carrier, the auxiliary component is at least one of sodium citrate, disodium ethylene diamine tetraacetate, sodium metavanadate, oxalic acid, zirconium oxychloride, yttrium nitrate or sodium carbonate; and the active component and the auxiliary component both account for 0.1-10% of the mass of the catalyst. The catalyst is used for preparing N-(1-ethyl propyl)-3, 4-dimethylaniline through hydrogenation, the reaction can be continuous, the safety performance is better, and the catalyst has high catalytic activity and stability.

This invention relates to a toothpaste flavoring with a long-lasting fresh breath effect and its preparation method. The core component of this toothpaste flavoring is modified menthol. Modified menthol reacts with amino acid compounds to form a menthol-amino acid complex, which is then coated with β-cyclodextrin to form a menthol-amino acid-β-cyclodextrin complex. This dual synergistic effect effectively prolongs the duration of its fresh breath effect. The toothpaste flavoring also includes 2,6-dimethylaniline, flavor enhancers, emulsifiers, stabilizers, aroma retardants, and preservatives to ensure aroma stability and safety for oral use. This invention provides a longer-lasting fresh breath effect, solving the problems of rapid evaporation and short-lasting freshness in traditional toothpaste flavorings, and has good market application prospects.

The present invention relates to the technical field of concrete materials. Disclosed are a modified epoxy resin and a preparation method therefor, a composition for an epoxy resin grouting material, an epoxy resin grouting material, a preparation method therefor, and a use thereof. The method for preparing the modified epoxy resin comprises: heating a polyhydroxy compound and an epoxy resin at 80-100ºC in a nitrogen atmosphere in the presence of a catalyst to obtain the modified epoxy resin, wherein the molar ratio of the polyhydroxy compound, the epoxy resin, and the catalyst is 1:1-2:0.05-0.1; the epoxy resin is a bisphenol A epoxy resin; the catalyst is selected from any one of sodium hydroxide, potassium carbonate, and dimethylaniline; and the polyhydroxy compound is selected from at least one of glycerol, ethylene glycol, propylene glycol, glucose, and butylene glycol. The epoxy resin grouting material of the present invention has more excellent toughness and lower viscosity, and good bonding strength and bonding durability with a concrete matrix.

The invention belongs to the technical field of fluorescent probes, and particularly relates to a near-infrared fluorescent probe compound as well as a preparation method and application thereof. 4-bromo-N, N-dimethylaniline, 5-formyl thiophene-2-boric acid and paeonol are adopted as reaction substrates, and a novel near-infrared fluorescent probe compound # imgabs0 is prepared through a simple two-step chemical reaction. The preparation method is short in reaction route, high in synthesis efficiency and mild in reaction condition; the method is simple and convenient to operate, few in side reaction, high in product purity, convenient to separate and purify and suitable for gram-level large-scale preparation; the obtained product has a very good application prospect in the field of biological medicines, and especially has a relatively good brain in-situ imaging effect.

The present application discloses a method for detecting N,N-dimethylaniline, comprising the following steps: preparing a PPY+N-MWCNT+MoS2 composite extraction head; performing headspace extraction of N,N-dimethylaniline with the composite extraction head; constructing a gas chromatography-mass spectrometry (GC-MS), and using the extraction head to detect N,N-dimethylaniline. The beneficial effects are as follows: The PPY+N-MWCNT+MoS2 composite extraction head has better extraction efficiency and mechanical stability for N,N-dimethylaniline. Applying the method of the present application to the detection of N,N-dimethylaniline in actual samples has good sensitivity and practicability.

The application provides a low-yellowing fluorine-free semi-alicyclic polyimide composition and a preparation method thereof, and relates to the technical field of polyimide preparation.The semi-alicyclic polyimide composition is prepared by polymerization reaction of diamine and dianhydride; the diamine comprises first diamine and second diamine; the first diamine is 4,4'-diamino diphenyl ether-2,2'-disulfonic acid and / or 4-(4-aminophenoxy)-2,6-dimethyl aniline; the second diamine is 4,4'-diamino dicyclohexyl methane and / or 3,3'-dimethyl-4,4'-diamino dicyclohexyl methane; and the dianhydride is fluorine-free dianhydride. The semi-alicyclic polyimide composition prepared by the application significantly improves the optical performance of the polyimide film prepared therefrom, and the anti-yellowing effect is significantly improved.

The present invention provides a catalyst system for ethylene oligomerization reaction, its preparation method and application, the catalyst system comprising cyclohexane and a metal complex of 2-formyl-1,10-phenanthroline chloride condensation 2,6-dimethylaniline and ethylaluminoxane dissolved in the cyclohexane. The present invention adopts ethylaluminoxane as an aluminum adjuvant and cyclohexane as a solvent, which can effectively increase the temperature of the ethylene oligomerization reaction when using the metal complex catalyst of 2-formyl-1,10-phenanthroline chloride condensation 2,6-dimethylaniline. At the same time, the ethylene oligomerization reaction can be initiated rapidly, run smoothly, have good repeatability, and the catalyst has high catalytic activity.

The invention belongs to the technical field of protective coatings, and provides a fast-curing water-based conformal coating and a preparation method thereof.The fast-curing water-based conformal coating is prepared from, by weight, 25-40 parts of epoxy acrylate, 30-40 parts of triglycidyl isocyanurate epoxy resin, 5-10 parts of N, N-dimethylformamide, 1-3 parts of a curing agent, 1-3 parts of a curing agent and 1-3 parts of a curing agent. The paint is prepared from the following components in parts by weight: 2-8 parts of N, N-dimethylaniline, 10-20 parts of talcum powder, 0.1-0.5 part of a defoaming agent, 0.1-0.5 part of a flatting agent, 1-2 parts of a dispersing agent and 1-5 parts of pigment. By reasonably selecting the defoaming agent and the dispersing agent, the obtained water-based conformal coating is high in curing speed and has good impact resistance, flexibility, salt spray resistance and adhesive force.

The invention discloses a waterproof fiber composite board and a preparation method thereof, and belongs to the technical field of fiber composite boards. The preparation method comprises the following steps: mixing and stirring fir wood fibers, maleic anhydride, benzoyl peroxide and N, N-dimethylaniline for reaction to obtain pretreated wood fibers; the pretreated wood fibers and phenolic resin with the solid content being 50% are mixed to obtain a wood matrix material, modified pollen, modified lotus leaf wax, stannous octoate and modified aerogel are added, and the mixture is stirred and mixed to obtain functional slurry; and pouring the functional slurry into a mold, and carrying out hot pressing treatment to obtain the waterproof fiber composite board. Chemical bonding of the modified aerogel, the pretreated wood fiber and the modified pollen is achieved through an isocyanate group, and a continuous heat preservation network is constructed to achieve the heat preservation property; phenolic resin, modified pollen and modified lotus leaf wax form double waterproof barriers, so that the problem that hydrophobic components are easy to migrate is solved; all the components have a synergistic effect, so that the product has excellent water resistance, antibacterial property, thermal insulation property, mechanical property and thermal stability.

The present invention discloses a method for preparing polyurethane microcapsule shells by direct crosslinking of cellulose and polyisocyanate, including: mixing cellulose crystals with deionized water uniformly to obtain an aqueous phase; mixing N,N-dimethylaniline, toluene, and polyisocyanate uniformly to form an oil phase; stirring the oil phase into the aqueous phase for 20 minutes to form an emulsion; and heating and stirring the emulsion, then standing the emulsion for 2 hours, cooling the emulsion to room temperature, and performing filtration, washing, re-filtration, and drying to obtain the polyurethane microcapsule shells. Rigid polyurethane structural shells with high-density carbamate groups are generated. Such direct crosslinking enhances the stability of microcapsules, enabling more reliable product quality.

The invention discloses 4-bromo-2, 6-dimethyl fluorobenzene and a preparation method thereof, and belongs to the technical field of organic synthesis. The method provided by the invention comprises the following steps: reacting 4-bromo-2, 6-dimethylaniline, a boron trifluoride ether complex and nitrite ester in a reaction system in the presence of an organic solvent at the temperature of 75-105 DEG C to obtain a material containing 4-bromo-2, 6-dimethyl fluorobenzene; wherein the weight ratio of the 4-bromine-2, 6-dimethylaniline to the boron trifluoride ether complex to the nitrite ester is 1: (0.93 to 1.75): (0.58 to 0.88). According to the reaction method, an unstable intermediate fluoborate does not need to be separated, the safety is high, the large-scale production yield is stable, the purity is high, and the amount of three wastes is low.

The invention belongs to the technical field of organic synthesis, and in particular to a kind of preparation method of 2,3-dimethylphenol. The preparation method of 2,3-dimethylphenol provided by the present invention comprises the following steps: 2,3-dimethylaniline, inorganic acid and water are subjected to salt-hydrolysis reaction to obtain crude 2,3-dimethylphenol; The crude 2,3-dimethylphenol is extracted to obtain oil phase and aqueous phase; The oil phase is sequentially neutralized, washed and distilled under reduced pressure to obtain the 2,3-dimethylphenol. The preparation method provided by the present invention is direct hydrolysis of salt under acidic conditions using 2,3-dimethylaniline as raw material, and step is simple, safe and efficient, and the ammonium salt of by-product can be recycled, and recovery process is relatively simple and environmentally friendly. Meanwhile, the 2,3-dimethylphenol product synthesized using this method has high purity and stable quality, and has good industrial value.

The application provides a double-curing acrylate-epoxy hybrid adhesive as well as a preparation method and application thereof, and belongs to the technical field of adhesives. The double-curing acrylate-epoxy hybrid adhesive is composed of component A and component B. The component A comprises tetrahydrofurfuryl methacrylate, isobornyl methacrylate, hydroxypropyl methacrylate, N,N-dimethylaniline, a toughening agent, a double-curing resin, wollastonite, fumed silica, solid glass microbeads, an antioxidant, a phosphate monomer and a multifunctional monomer. The component B comprises benzoyl peroxide, an epoxy resin, wollastonite and fumed silica. The double-curing acrylate-epoxy hybrid adhesive prepared by the application can realize the combination of high-temperature strength and normal-temperature toughness, and solves the problem of easy gelation of a traditional NCO-containing system.

This invention discloses a berberine-dimethylaniline photosensitizer, its preparation method, and its application, belonging to the field of biomedical technology. The method involves sequentially reacting berberine with magnesium methyl bromide via Grignard addition, followed by bromomethylation with N-bromosuccinimide, and basic condensation with dimethylaminobenzaldehyde, then demethylating under high temperature and vacuum to obtain the active berberine-dimethylaniline. Finally, it undergoes weakly alkaline treatment to obtain the inactivated berberine-dimethylaniline. This invention introduces the electron-donating group dimethylaniline onto the berberine backbone, constructing an electron push-pull structure that red-shifts the absorption wavelength, facilitating deeper tissue penetration. Furthermore, this photosensitizer maintains high activity in the weakly acidic microenvironment of tumors while remaining inactive under normal physiological conditions, thereby achieving intelligent "on-off" regulation based on pH differences, improving the safety and precision of photodynamic therapy for tumors.