925 results about "End-group" patented technology

The invention belongs to the technical field of optical materials, and discloses a holographic polymer dispersed liquid crystal composition, a holographic grating and a preparation method. The composition comprises the following components in parts by mass: 0.5-1.5 parts of a photoinitiator, 2-5 parts of a co-initiator, 15-20 parts of a first monomer, 15-20 parts of a second monomer, 10-15 parts of a third monomer, 10-15 parts of a solvent and 10-20 parts of mixed liquid crystal. Wherein the first monomer is a monofunctional acrylic monomer, the second monomer is a bifunctional acrylic monomer, the third monomer is a polyfunctional acrylic monomer, the mixed liquid crystal comprises 10-25 wt% of a monomer liquid crystal and 75-90 wt% of a nematic liquid crystal, and the monomer liquid crystal contains fluorine as a benzene ring substituent and contains cyano or isothiocyano as an end group. Through cooperation of the monomer liquid crystal and the nematic liquid crystal in the mixed liquid crystal and cooperation of fluorine atoms and cyano / isothiocyano groups in the monomer liquid crystal, the holographic grating prepared from the composition has the characteristics of low haze and high diffraction efficiency, and the grating can be thinner, so that the requirements of light weight and clearness of AR glasses can be met.

The invention discloses a high-cohesiveness polyimide composite film capable of being used for a flexible copper-clad plate and a preparation method of the high-cohesiveness polyimide composite film. The polyimide composite film is composed of a thermosetting polyimide supporting layer and a thermoplastic polyimide bonding layer arranged on at least one face of the thermosetting polyimide supporting layer. An interface layer formed by reacting amino-terminated hyperbranched polyamide grafted silicon dioxide particles with thermosetting polyamide acid is embedded between the thermosetting polyimide supporting layer and the thermoplastic polyimide bonding layer, and an end group of thermoplastic polyimide contains an imidazole ring capable of forming a complex with copper. The amino-terminated hyperbranched polyamide grafted silicon dioxide particles are embedded into the interface of the thermosetting layer and the thermoplastic layer, so that the contact area of the supporting layer and the adhesive layer is increased; the polyimide composite film with high cohesiveness, high dimensional stability, high heat resistance and low glass transition temperature is prepared.

The invention relates to the technical field of BOPP (biaxially-oriented polypropylene) films, in particular to a scratch-resistant adhesive-free matt film and a preparation method thereof, and the scratch-resistant adhesive-free matt film comprises a matt layer, a core layer and a thermal composite layer which are sequentially arranged, the matt layer comprises co-polypropylene, high-density polyethylene, 2.0-2.5 wt% of linear alkyl silicone (the weight-average molecular weight is 12-150 thousands, and the surface tension is 42-45 mN / m) taking maleic anhydride modified aziridine as a terminal group, and 2000-4000 ppm of spherical polymethyl methacrylate (the particle size D50 is 4.0-5.0 microns); the core layer comprises homo-polypropylene; and the thermal composite layer comprises an ethylene-vinyl acetate copolymer and 2000 to 4000 ppm of a spherical anti-blocking agent. According to the scratch-resistant adhesive-free matt film, through collaborative design of the components of the matt layer and the thermal composite layer, balance of scratch resistance, high surface tension (printing applicability) and winding and unwinding smoothness of the surface of the matt layer is achieved, and a solution for the scratch-resistant generality problem of the matt surface of the high-end BOPP matt film is provided.

The present application relates to the technical field of polyimides and relates to a preparation method for a high-performance polyimide and an application thereof, aiming to solve the problems in the prior art such as numerous side reactions and severe impact on transparency caused by an excessively high imidization reaction temperature during the use of a high-temperature thermal imidization method for the preparation of polyimides. The preparation method comprises: (1) preparing a polyamic acid solution; (2) adding a chemical catalyst and a polyamic acid solution to partially complete an imidization reaction; (3) adding an end group auxiliary agent, performing coating with the solution, heating, and maintaining the heat to complete the imidization reaction; and (4) carrying out high-temperature treatment to obtain a high-performance polyimide. The present application can significantly reduce numerous side reactions present in a traditional imidization reaction, eliminate an adverse effect of high-temperature imidization on the optical performance, greatly improve the mechanical properties, heat resistance, optical performance, etc. of a material, and also achieve both high heat resistance and high transparency.

The invention discloses a bidirectional reversible conversion method and system between a peptide molecule SMILES and a sequence expression. The core innovation lies in that a new sequence description syntax is defined to retain information of a polypeptide special bond and specific modification of amino acid; a main chain atom index and adjacency traversal topology identification algorithm is adopted, and end group and topology integrated detection and coding are carried out; a residue recognition algorithm for main chain cutting and template library matching is compatible with any standard or non-standard amino acid residues, an extensible end group library / monomer template library and an automatic increment mechanism, and automatic recognition and sequence annotation of S-S disulfide bonds; the invention relates to a high-fidelity assembly algorithm of HELM anchor points and topology aware cyclic peptide processing. The method solves the problems of incapability of supporting a complex polypeptide topological structure, poor reversibility, insufficient expansibility of a monomer library and the like in the prior art, can be widely applied to scenes of quantitative structure-activity relationship model construction, large-scale polypeptide data cleaning and the like, and has remarkable practicability and innovativeness.

The invention discloses a high-CTI (comparative tracking index) flame-retardant polycarbonate composite material which comprises the following components in parts by weight: 70-80 parts of polycarbonate; 8-12 parts of a phosphate flame retardant; 3-7 parts of low-melting-point glass powder; 7-15 parts of titanium dioxide; and more than or equal to 80 mol% of end groups in the polycarbonate are terminated. Through cooperation of the phosphate flame retardant, the low-melting-point glass powder and the titanium dioxide, 1.5 mm V-0 flame retardance and even 1.0 mm flame retardance can be achieved on the premise that fluorine-containing anti-dripping agents such as PFAS are not contained and low filler filling is achieved, and meanwhile the CTI larger than or equal to 600 V is achieved.

A type of additive based on a fluorinated carbamate prepolymer, a preparation method therefor, and a use thereof in the preparation of a medical fluorinated anticoagulant polyurethane material. The preparation method of the additive comprises: reacting a polyester / polyether diol, a diisocyanate and a fluorinated small-molecule diol, to obtain a carbamate prepolymer having an isocyanate end group, and then capping with a monohydric alcohol having a fluorinated carbon chain, to obtain an additive based on a fluorinated carbamate prepolymer. The additive has a high fluorine content. After being blended with a polyurethane masterbatch, fluorine atoms having low surface energy can be enriched on the surface of the material, and the fluorine atom content on the surface of the material can be as high as 60%. This effectively reduces the adhesion of plasma proteins, cells and platelets on the surface of the material, providing the medical polyurethane material with an excellent anticoagulant effect. In addition, it maintains the excellent mechanical properties of polyurethane, and is thus widely applicable in the preparation of medical fluorinated anticoagulant polyurethane materials.

The invention relates to the technical field of coatings, and particularly discloses a high-wear-resistance and high-toughness polyurethane floor coating and a preparation method thereof. According to the technical key points, the high-wear-resistance and high-toughness polyurethane floor coating is prepared from the following components in parts by weight: 100 parts of cross-linked polyurethane matrix resin, 1 to 3 parts of nano ZnO (at) MCM-41 catalyst, 10 to 15 parts of core-shell microsphere powder filler, 5 to 10 parts of fiber filler, 15 to 20 parts of reactive diluent and 1 to 3 parts of photoinitiator, the cross-linked polyurethane matrix resin is composed of a disulfide bond-containing polyurethane prepolymer and an ultraviolet curing acrylate end group; the core-shell microsphere powder filler is prepared by taking a polyurethane-acrylate copolymer as a shell layer and diamond and silicon carbide composite particles as a core layer, and the particle size of the core-shell microsphere powder filler is 200-500nm. The polyurethane floor coating prepared in the invention has excellent performance, and the coating has high wear resistance and high toughness.

The invention discloses an ether polymerization inhibitor special for a butadiene extraction system and a preparation method of the ether polymerization inhibitor. The ether polymerization inhibitor comprises the following raw materials: a polymerization inhibitor intermediate, a solvent and a dispersing agent, the production process comprises the following steps: preparing a polymerization inhibitor intermediate, preparing a solvent, compounding, feeding and mixing, filtering, removing impurities and detecting. According to the method, firstly, a polymerization inhibitor 701 and diethylene glycol normal pressure etherification process is adopted, and beta-hydroxyethyl methyl ether is introduced to seal a terminal group, so that the power consumption is reduced, the generation of byproducts is inhibited, the solubility of an intermediate acetonitrile is improved to be greater than or equal to 30g / L, and the anti-interference performance is greatly enhanced; the solvent doped with a small amount of silane modified nano diatomite is prepared, impurities can be adsorbed, metal ions can be chelated, the dispersing agent can be assisted to be evenly distributed, the problems that a pure water solvent is single in function and the dispersing agent is prone to agglomeration are solved, and the polymerization inhibition efficiency and the stability of an extraction system are guaranteed.

The invention discloses polyphenylene sulfide resin and a preparation method thereof. The weight-average molecular weight of the polyphenylene sulfide resin is 20000-50000, the molar ratio of a sulfydryl terminal group to a chlorine terminal group is 1-9, and the content of the chlorine terminal group is 15-60 [mu] mol / g. In the preparation method of the polyphenylene sulfide resin, a sulfur source, an alkali metal hydroxide and a dihalogen aromatic compound are taken as raw materials and subjected to a polymerization reaction in N-methyl pyrrolidone, and self-blocking is performed by accurately controlling the adding time of the dihalogen aromatic compound, so that controllable adjustment of an active end group is realized. The polyphenylene sulfide resin provided by the invention has excellent processability, and has excellent reactivity with silane coupling agents such as gamma-aminopropyltriethoxysilane and the like.

The invention discloses a high-impact precipitation-resistant halogen-free flame-retardant modified nylon 12 material and a preparation method thereof. The nylon 12 material is prepared from the following components in parts by weight: nylon 12 with specific end group content, in-situ grafting toughening agent master batch, in-situ fiber forming flame retardant master batch and 0 to 4 parts of processing aid. The preparation method of the in-situ grafted toughening agent master batch is adopted, the nylon 12 resin with specific end group content is matched, and after the in-situ reaction of the high-content polar monomer of the grafted toughening agent and the amino group at the end of the nylon 12 is complete, a considerable number of polar groups are still reserved to be chemically bonded with the amino group in an MCA compound system; the dispersion condition of the flame retardant in the nylon 12 resin is effectively improved; meanwhile, the acrylic acid modified polytetrafluoroethylene forms a microfibrillated network in situ in the mixing process of the continuous internal mixer, precipitation of a flame retardant can be inhibited, the material is endowed with an anti-dripping characteristic, and finally the halogen-free flame-retardant modified nylon 12 material with high impact and precipitation resistance characteristics is obtained.

The invention relates to the technical field of biopolymer materials, in particular to a preparation method and application of a cationic polymer gene vector with a fluorinated end group. The invention provides a cationic polymer with a fluorinated end group. The structure of the cationic polymer is shown in the specification. According to the method, a fluorinated group is introduced through a fluorinated initiator by a one-step method to initiate synthesis of various terminal group fluorinated linear polyethyleneimine F-PEI with different molecular weights, the gene transfection efficiency is improved by introduction of the fluorine group, and high-efficiency DNA transfection is realized. The gene vector can achieve an efficient transfection effect in the cell transfection process, the toxicity generated to cells in the transfection process is small, gene molecules can be effectively and safely conveyed into the cells, and the gene transfection vector has the advantages of being efficient, low in toxicity, low in price, easy to synthesize and the like. The method has the advantages of simple reaction, easily available raw materials, low preparation cost, easily controlled molecular weight, high yield and simple post-treatment, and is suitable for large-scale production. # imgabs0 #

In some aspects, the present disclosure provides systems for forming hydrogels that comprise (i) a reactive multi-arm polymer that comprises three or more polymer arms linked to a core region, each arm comprising a polyether segment and a reactive moiety comprising a cyclic imide carboxy-C1-C5-alkyl ester end group or each arm comprising a polyether segment and a reactive moiety comprising a C2-C6-isocyanoalkyl end group and (ii) a polyamino compound comprising at least two amino (-NH2) groups, wherein the reactive multi-arm polymer and the polyamino compound react to form a crosslinked hydrogel that does not contain ester groups and has long-term stability in vivo. In some aspects, the present disclosure provides methods of treatment using such systems and hydrolysis-resistant crosslinked hydrogels formed from such systems.

The invention relates to a PVB (Polyvinyl Butyral) film for PDLC (Polymer Dispersed Liquid Crystal) dimming glass, a preparation method and the PDLC dimming glass, and belongs to the technical field of dimming glass. The PVB film for the PDLC dimming glass comprises PVB resin and a plasticizer, at least one end group of the plasticizer is a benzoate group, and the plasticizer belongs to benzoate. Through molecular structure design, the main chain of the plasticizer can be a polyether type [-CH2-CHY-O-] n chain segment or a polyol skeleton, and meanwhile, benzoate groups or specific end group structures (such as branched chain alkyl, aromatic hydrocarbon and the like) are introduced, so that the interaction (such as hydrogen bond damage, dipole interaction, pi-pi accumulation and the like) between the plasticizer and PVB resin is enhanced, and the plasticizer can be used for preparing PVB resin. By introducing structures such as branched chains and aromatic rings, the steric hindrance and rigidity of molecules are greatly improved, and migration and precipitation phenomena of the plasticizer in the PVB film are effectively inhibited.

The invention discloses an anti-corrosion oil-resistant corrugated pipe inner layer coating and a preparation method thereof. The coating comprises acrylic acid modified epoxy resin, epoxy phosphate, an auxiliary agent, a curing agent and water. The preparation method comprises the steps of synthesis of acrylic acid modified epoxy resin, synthesis of epoxy phosphate, epoxy mixing reaction, neutralization reaction, coating preparation and the like. The preparation method comprises the following steps: adding a copolymer side chain with acrylic acid, styrene and vinyl siloxane to a side chain in epoxy resin to obtain acrylic acid modified epoxy resin, and introducing a phosphate end group to an end group of the epoxy resin to obtain epoxy phosphate; epoxy phosphate and acrylic acid are used for modifying epoxy resin, and an initiator is supplemented for secondary polymerization chain extension and cross-linking reaction, so that the obtained epoxy mixture has the curing film stability of an epoxy coating, the compact isolation effect of acrylic resin, the high adhesiveness of silicon resin to a metal surface and the phosphating treatment characteristic of phosphoric acid; and the paint has excellent water resistance, oil resistance, rust resistance and other corrosion resistance.

The present invention relates to the technical field of liquid crystal polymer modification, and particularly relates to a crosslinked liquid crystal polymer, a preparation method thereof and an application. The crosslinked liquid crystal polymer is formed by crosslinking an aromatic liquid crystal polyester and a polyfunctional polyester oligomer in a mass ratio of 100:(0.4 - 5); the repeating unit of the polyfunctional polyester oligomer has the structure shown in formula (I) or formula (II), wherein the end groups of R1 - R6 are each independently selected from a carboxyl group and an acetoxy group, and at least one of R1, R2 and R3 in formula (I) or at least one of R4, R5 and R6 in formula (II), and its molecular chain contains a -C(O)-Ar-C(O)- link; Ar represents an aromatic ring. The crosslinked liquid crystal polymer has the advantages of high modulus and high temperature resistance, and can also maintain good flexibility and film-forming property, and thus can be formed into a diaphragm by diaphragm forming to prepare a diaphragm material. #imgabs0#

The embodiment of the invention provides a connecting unit for chemical modification of a nucleic acid end group, a preparation method of the connecting unit and a nucleic acid probe. The connecting unit for chemical modification of the nucleic acid end group has a triethylene glycol structure, and the connecting unit has the following structure. Therefore, the connecting unit with the triethylene glycol structure is relatively simple in synthesis process, relatively high in yield, efficient in synthesis, good in nucleic acid end group chemical modification effect, applicable to connection of various types of probe molecules and nucleic acid molecules, capable of simply and efficiently preparing nucleic acid probes and wide in application range.

The present invention discloses a wear-resistant and tear-resistant polyamide elastomer composition and a preparation method and application thereof, and belongs to the technical field of modified materials. The wear-resistant and tear-resistant polyamide elastomer composition is prepared by weight from 87.1 to 95.9 parts of polyamide elastomer, 3 to 10 parts of wear-resistant agent, 0.2 to 1 part of cross-linking agent, 0.4 to 1 part of antioxidant, 0.1 to 0.6 parts of nucleating agent, 0.2 to 0.6 parts of dispersant, 0 to 2 parts of masterbatch, and 0 to 0.01 parts of fluorescent brightener. The present invention adopts polyamide elastomer as a substrate, and generates a cross-linking structure through a trifunctional cross-linking agent and an amide bond and / or an end group (amino, carboxyl, hydroxyl) in a polyamide elastomer molecular chain to improve the tear strength of the composition, and adds a polymer wear-resistant agent (PTFE and / or POM powder) to improve the wear resistance and resilience of the composition, so that the badminton racket line nails prepared by the composition of the present invention have playability and durability.

The invention provides a meltable fluororesin end group fluorination treatment system and a meltable fluororesin end group fluorination treatment process. The system comprises at least two feeding tanks, a reaction tower and a cooling tank, the top ends of the feeding tanks are connected with an N2 gas pipeline and are provided with resin raw material inlets, and the N2 gas pipeline is provided with a valve; the top end of the reaction tower is connected with the bottom end of the feeding tank through a pipeline, a valve is arranged on the pipeline, the top end of the reaction tower is connected with a tail gas treatment pipeline, the bottom end of the reaction tower is connected with an N2 / F2 mixed gas pipeline and an N2 gas pipeline, and a valve is arranged on the pipeline; the top ends of the cooling tanks are connected with the bottom end of the reaction tower through pipelines, valves are arranged on the pipelines, the bottom ends of the cooling tanks are connected with a product output pipeline and an N2 gas pipeline, and valves are arranged on the pipelines. The system can ensure that the fluorination reaction of the end group of the meltable fluororesin is continuously carried out, the production efficiency of the fluorination reaction is remarkably improved, the system avoids the overflow of fluorine, and the safety of the working environment is improved.

The invention relates to a tin-free one-component moisture-curable composition, comprising at least one organic polymer containing reactive silane end groups, at least one latent curing catalyst comprising at least one latent amine and at least one latent carboxylic acid, preferably adhesion promoters, plasticizers, fillers and optionally additives. The one-component moisture curable composition can be formulated to show excellent properties for storage stability and curing speed and is free of tin-based catalysts.

The invention relates to the technical field of high polymer materials, and discloses a synthesis method of low-chlorine polyphenylene sulfide nitrile, which comprises the following steps: carrying out pressurized prepolymerization reaction on a sodium sulfide solution and p-dichlorobenzene to obtain a first prepolymerization reaction product; carrying out copolymerization prepolymerization reaction on the first prepolymerization reaction product and 2, 6-dichlorobenzonitrile to obtain a second prepolymerization reaction product; carrying out heating polymerization reaction on the second prepolymerization reaction product and benzyl chloride to obtain a heating polymerization reaction product; and raising the temperature of the polymerization reaction product, and carrying out phase separation to obtain the low-chlorine polyphenylene sulfide nitrile. Under the condition of no auxiliary agent, the polymerization process of inert gas pressurization and phase separation is adopted, benzyl chloride is applied to adjust the end group, low-chlorine high-molecular-weight polyphenylene sulfide nitrile can be obtained in a short time, the production efficiency of synthesizing polyphenylene sulfide nitrile can be improved, the purification process of byproduct sodium chloride is shortened, auxiliary agent recovery is omitted, and the production cost is reduced. The engineering construction investment is reduced, and the production cost for manufacturing the polyphenylene sulfide nitrile is greatly reduced.

The invention provides an antibacterial cationic hydrogel adhesive and a preparation method thereof. The antibacterial cationic hydrogel adhesive is prepared from the following raw materials: polyphenol grafted epsilon-polylysine; the end group of the four-arm polyethylene glycol is phthalic dialdehyde; the polyphenol grafted epsilon-polylysine polymer has a structure as shown in a formula I or a formula II. The hydrogel adhesive contains epsilon-polylysine, so that the hydrogel adhesive can resist bacteria for a long time, and drug resistance is avoided; the grafted polyphenol functional group can effectively remove excessive free radicals and has an anti-oxidation function, so that wound healing is promoted, and tissue adhesiveness can be enhanced; and the tissue adhesiveness is provided by utilizing the rapid cross-linking gel formation of o-phthalaldehyde-amine.

The invention relates to the technical field of organic photoelectric materials, and particularly discloses a non-condensed ring small molecule acceptor material based on a quinonoid structure as well as a preparation method and application of the non-condensed ring small molecule acceptor material. According to the invention, easily available 1, 4-diacetyl piperazine-2, 5-diketone is used as a center, an alkyl chain and Ar are used for modification, EG is used as an end group, the non-condensed ring A-D-A '-D-A type structure acceptor material based on a quinone structure is constructed, and the general formula is shown in the specification. Wherein the PCE of the acceptor material which is modified by bithiophene and takes 2-(3-ethyl-4-oxothiazolidine-2-subunit) malononitrile as a terminal group reaches 15%. The non-condensed ring small molecule acceptor material based on the quinonoid structure is simple in synthesis process, and an effective strategy is provided for solving the problem of the overall performance of an organic solar cell.

The invention relates to a method for preparing high-molecular-weight polyethylene furandicarboxylate by a one-step method, and belongs to the technical field of bio-based polyester materials. The method comprises the following steps: weighing raw materials including 2, 5-furandicarboxylic acid, ethylene glycol, an end group regulator, a protective agent, a decarboxylation inhibitor and a catalyst, mixing and adding into a reaction container, introducing nitrogen, maintaining the pressure of the nitrogen in the reaction container to be 50-150 kPa, carrying out esterification reaction, heating and vacuumizing until the pressure is less than or equal to 50 Pa after the esterification reaction is completed, and carrying out polycondensation reaction to obtain the 2, 5-furandicarboxylic acid. And carrying out extrusion and drying so as to obtain the high-molecular-weight polyethylene furandicarboxylate, wherein the high-molecular-weight polyethylene furandicarboxylate is obtained. According to the method, the FDCA conversion rate is larger than or equal to 98%, the number-average molecular weight of the obtained product is larger than or equal to 32 kg / mol, no heavy metal residues exist, and the method is suitable for large-scale production of high-end bio-based packaging materials.

The invention discloses vinyl fluorine-containing polysiloxane and a preparation method thereof, and relates to the technical field of organic silicon materials. According to the invention, high-activity fluorine-containing potassium hydroxide silanolate is used as a catalyst to realize high-efficiency catalysis; d3F serves as a main monomer, D3Vi serves as a comonomer, deionized water is introduced for the first time to serve as a retarder, and implosion is effectively inhibited; vinyl dimethyl ethyoxyl silane is used as an end-capping reagent for the first time, end group vinylation is synchronously realized, and end group and side chain divinyl polysiloxane is prepared; through cooperation of ring-opening polymerization and condensation polymerization, the reaction process is mild and controllable, the product viscosity is controllable, the crosslinking activity is high, and the application range is remarkably widened.

The invention relates to a one-component moisture-curable composition, comprising at least one organic polymer containing on average at least two reactive silane end groups, at least one reactive plasticizer containing on average 1 to 1.5 reactive silane end groups, optionally a filler and optionally at least one additive. The one-component moisture curable composition can be formulated to show excellent properties for application in non-bleed sealants. The invention also reduces the amount of hazardous phthalate-containing plasticizers.

The invention belongs to the technical field of high-molecular polymer synthesis, and particularly relates to a high-performance special polyether material with a directionally-modified terminal group and a preparation method of the high-performance special polyether material. The preparation method comprises the following steps: sequentially grafting 4-bromobenzoate to methylene of crown ether and aminating bromine atoms to prepare an intermediate, and reacting amino of the intermediate with isocyanate-terminated polyether to form a urea bond, so that a terminal group of a polyether structure is chemically modified, and a special polyether material is endowed with separation performance; when the composite membrane is applied to a nanofiltration separation membrane, the water permeability can be remarkably improved, and magnesium ions and lithium ions can be efficiently and selectively separated. According to the invention, a terminal group of a polyether structure is chemically modified through a specific reaction, and the application potential of a special polyether material in emerging fields such as high-performance separation membranes is expanded.

The invention discloses a preparation method of modified thermostable polycaprolactone, and belongs to the technical field of high polymer materials. The method comprises the following steps: selecting branched monomers such as 3-methyl-epsilon-caprolactone, inhibiting molecular chain slippage through a side group steric effect, and improving chain rigidity; a super-crosslinking metalloporphyrin porous material catalyst is adopted; (3) introducing a light / heat reversible group to an end group; and (4) optimizing process conditions and narrowing molecular weight distribution. Experiments show that the modified PCL obtained by the method is high in thermal decomposition temperature, small in melt flow rate change rate, low in yellowing index and high in tensile strength, and the comprehensive performance of the modified PCL is far better than that of the modified PCL obtained by a traditional method. The material is suitable for the fields of medical instruments, intelligent packaging and the like, and has the characteristics of high thermal stability, rapid shape recovery and controllable degradation.

The invention discloses cyano-terminated modified polysulfone and a preparation method thereof. The terminal cyano group is selected from at least one of the following groups: n, m, p, q and r are independently 0 or 1; r1, R2, R3 and R4 are respectively and independently selected from any one of H, methyl, trifluoromethyl and cyano. Through molecular structure design, a polar group (cyano) with large dipole moment is introduced into the end group of polysulfone to prepare the cyano-terminated modified polysulfone and the film thereof. According to the polysulfone provided by the invention, the cyano group at the chain end has a relatively large degree of freedom, and when the cyano group is subjected to sub-Tg polarization, the steric hindrance is relatively small. Therefore, the cyano-terminated modified polysulfone can maintain relatively low dielectric loss and high Tg while increasing the dielectric constant.

The invention relates to a thermal viscosity-reducing adhesive, a preparation method thereof and a thermal viscosity-reducing adhesive product. The heat-reduced adhesive is prepared from the following raw materials in parts by weight: 180-230 parts of polyacrylate, 1-5 parts of a cross-linking agent and 20-50 parts of a first solvent; the polyacrylate is prepared from the following raw materials: 60 to 80 parts of a soft monomer, 10 to 30 parts of a hard monomer, 1 to 5 parts of a functional monomer, 25 to 45 parts of a polyacrylate monomer, 0.2 to 0.4 part of an initiator and 80 to 100 parts of a second solvent; two end groups of the polyacrylate monomer are double bonds, and the monomer contains a polycaprolactone structure; the polyacrylate monomer is prepared from the following raw materials in parts by weight: 1 to 5 parts of isocyanate-based acrylate, 10 to 16 parts of polycaprolactone diol, 0.01 to 0.05 part of a water removal agent, 0.05 to 0.1 part of a polymerization inhibitor and 10 to 25 parts of a third solvent. Reversibility can be achieved, the visbreaking effect is excellent, and no adhesive residue exists.