35results about How to "Reduce intertwining" patented technology

The invention relates to a high voltage static power shuttle nano-spinning device. The device is composed of a spinneret nozzle, a liquid storage cavity, a metal valve needle, an adjusting cap, a liquid supply tank, a multifunctional high voltage static generator, a cavitation machine, a cavitation machine deckle rod, a positive pressure power pump, a positive pressure power pipe, a siphon type feed pipe, a net structure electrode, a receiving substrate, an unwinding roller, a winding roller, nanofiber, a constant temperature system, a ventilating system, an illuminating system and an environment isolation box. A high voltage static power shuttle body is formed by the spinneret nozzle, the liquid storage cavity, the metal valve needle, the adjusting cap and a shell. A high voltage static power shuttle is jointly formed by the spinneret nozzle, the liquid storage cavity, the metal valve needle, the adjusting cap, the shell, the multifunctional high voltage static generator, a liquid storage tank, the siphon type feed pipe, the positive pressure power pipe, the cavitation machine, the cavitation machine deckle rod, an output line, the ventilating system, the illuminating system, a humidity and temperature regulator and the box. Through the establishment of the high voltage static power shuttle and the adjustment of the size of the spinneret nozzle, the static field intensity, the pressure and the frequency of the cavitation machine, the spinning speed and the diameter of the nanofiber can be adjusted, and the high voltage static power shuttle nano-spinning device has the advantages of being high in spinning efficiency, free of blocking, easy to clean, safe, reliable, easy and convenient to operate, environmentally friendly and the like.

The invention relates to polyester polyol with a special structure, in particular to polyester polyol for synthesizing moisture cured polyurethane hot melt adhesives. The polyester polyol is prepared from three kinds of monomers A, B and C through esterification reaction, wherein the A is at least one kind of long straight chain binary acid, and the long straight chain binary acid refers to straight chain binary acid containing eight carbon atoms or above in the carbon chains; the B is at least one kind of long straight chain dihydric alcohol, and the long straight chain dihydric alcohol refers to the straight chain dihydric alcohol containing five carbon atoms or above in the carbon chain; the C is at least one kind of long branch chain dihydric alcohol, the long branch chain dihydric alcohol refers to dihydric alcohol with linear straight carbon chain and at least one long branch chain structure, and the long branch chain structure refers to carbon chains containing two methylene or above. The synthesized polyester polyol has the advantages of high molecular weight and low normal temperature viscosity. When the polyester polyol provided by the invention is used, the polyurethane hot melt adhesives with low melt viscosity can be generated through the reaction with isocyanate on the premise of not increasing the content of the isocyanate.

The invention discloses a construction method of a non-excavation top pipe pre-stress beam. The construction method comprises the sequentially-executed steps of concrete top pipe construction, steel top pipe construction, pre-stress system construction, anchor bearing plate mounting and pre-stress tendon tensioning, pre-stress beam forming through concrete top pipe interior pouring, and connectionof the pre-stress beam and an earthen ruin foundation bearing table. On the basis of ensuring that pre-stress beam construction meets construction requirements, destruction of an excavation-type construction mode on ruin soil bodies is reduced, it is effectively ensured that the ruin soil bodies are complete, the good conditions are created for protection and research work of ruins, the influences of excavating a large amount of earthwork on the aspects such as earthwork transportation and dust raising pollution are reduced, and the impact on the environment is lowered.

The invention provides boron adsorption resin as well as a preparation method and application thereof, and the preparation method comprises the following steps: 1) uniformly mixing an oil phase consisting of glycidyl methacrylate, a cross-linking agent, a pore-foaming agent and benzoyl peroxide, dispersing the oil phase in salt water containing a dispersing agent, carrying out suspension polymerization reaction, and separating from reaction liquid to obtain copolymerized beads; and 2) uniformly mixing the copolymerized beads, water and a polyhydroxy compound, and carrying out hydrothermal reaction to obtain the boron adsorption resin. According to the method disclosed by the invention, an organic solvent which is difficult to degrade is not used, the method is green and environment-friendly, the process operation is simple and convenient, and the resin has better pollution resistance and longer service life, and has higher adsorption selectivity and adsorption capacity on boron in the salt lake brine.

The invention relates to a window side wall water seepage detection device for constructional engineering. The device comprises a movable base, a rotating pipe rotationally connected to the movable base around the axis of the rotating pipe, a driving mechanism for driving the rotating pipe to rotate, a liquid conveying mechanism for conveying liquid into the rotating pipe, spraying pipes hinged toone end of the rotating pipe, and a folding and unfolding mechanism for adjusting the spraying pipes to be unfolded or folded, wherein the multiple spraying pipes are distributed around the axis of the rotating pipe. The window side wall water seepage detection device has the effect of reducing potential safety hazards existing when water seepage detection is conducted on the window side wall.

The invention discloses an antistatic polyester film, which comprises a base material and an antistatic layer on at least one surface of the base material, and the antistatic layer is formed by uniformly dispersing the following raw materials in percentage by weight: 15-30% of aqueous carbon nanotube dispersion liquid, 5-15% of modified acrylic resin emulsion, 5-15% of modified acrylic resin emulsion, 5-15% of polyester resin, 5-15% of polyester resin, 5-15% of polyester resin, 5-15% of polyester resin, 5-15% of polyester resin, 5-15% of polyester resin, and the balance of polyester resin. 0.1%-3% of a cross-linking agent, 0.1%-1% of a wetting agent and 51%-80% of deionized water. The preparation method comprises the following steps: modifying acrylic resin by utilizing epoxy resin and a catalyst to obtain epoxy modified acrylic resin emulsion, and reacting epoxy groups in the epoxy modified acrylic resin emulsion with the acrylic resin to form a block copolymer; a three-dimensional network structure is formed by thermocuring in online coating and transverse synchronous stretching and shaping of a base material with water-dispersed carbon nanotubes and a cross-linking agent, so that the cross-linking density is improved, mutual winding and lap joint of the carbon nanotubes are effectively reduced, the adhesive force between a bottom coating and a functional coating is increased, and excellent chemical stability is achieved.

The invention provides a low-viscosity high-speed cigarette adhesive prepared from seed emulsion, a vinyl acetate monomer, an oxidant, an initiator, a capturing agent, an alcohol compound, a pH regulator and water, wherein the seed emulsion is one or combination of more of vinyl acetate-ethylene emulsion, vinyl acetate-acrylate emulsion, a vinyl acetate homopolymerized emulsion, the seed emulsionhaving solid content of 40.0-65.0% and viscosity of 500-5000 mPa*s. In the invention, firstly, the protective colloid in the emulsion is broken to reduce the viscosity, and then the stable emulsion system is reconstructed through polymerization, and the generation quantity of new emulsion particles is controlled, thus producing the emulsion. The viscosity of the emulsion can be lowered to 200 mPa*s, which not only satisfies the cigarette lap adhesion at the machine speed of 14,000-16,000 / min but also can be used for adhesion of common materials, such as paper processing, coating decoration, nonwoven clothes, carpets, etc. The adhesive is simple in preparation method and is suitable for industrial production.

The invention discloses amino-silicone oil modified waterborne polyurethane and a preparation method thereof. The amino-silicone oil modified waterborne polyurethane comprises the following raw materials in parts by weight: 12.5-14.7 parts of polyester polyol, 4.88-5.0 parts of polyisocyanate, 0.02-0.04 part of a catalyst, 0.9-1.1 parts of a hydrophilic chain extender, 0.6-1.5 parts of a modifier,9.0-11.0 parts of a solvent, 0.6-0.8 part of a neutralizer, 0.02-0.04 part of a post-chain extender and 42.0-48.0 parts of deionized water. The amino-silicone oil modified waterborne polyurethane hasmaximum water absorption rate of 7.8%, maximum tensile strength of 30.28 MPa, and minimum elongation at break of 458.93%. The preparation method comprises the following steps: subjecting polyester polyol to reacting with polyisocyanate under the action of the catalyst to obtain a prepolymer; introducing the chain extender on the basis of the prepolymer, subjecting the prepolymer to reacting withthe modifier, and introducing alkoxy-terminated amino silicone oil into the prepolymer; and finally, adding the deionized water for high-speed emulsification to prepare the modified amino-silicon oilmodified waterborne polyurethane with good emulsion stability and latex film water resistance. The method is simple in process step, easy to operate and good in repeatability.

The invention discloses an air purification device for a smart home. The device comprises a shell and a dust collector, the dust collector is fixed to the bottom of the shell, a vortex core is rotationally connected to the center of the interior of the shell, a first magnetic ball is arranged on one side of the surface of the vortex core, and a dust removal device is arranged at the bottom of the inner wall of the shell. An air suction mechanism is fixed to the end, close to an air outlet, of the interior of the shell, one end of the vortex core is fixedly connected with one end of the air suction mechanism, a speed reducer is arranged between the vortex core and the air suction mechanism, and a negative ion generator is arranged at the position, close to the air suction mechanism, of the interior of the shell. The invention relates to the technical field of air purification. According to the air purification device for the smart home, the anti-blocking purpose is achieved, hair, fluff and other flexible filaments can be treated in time, mutual winding is avoided, the blocking situation is reduced, air purification is facilitated, the air purification effect is good, and the use performance is improved.

The invention discloses a yarn feeding flexible clamping device for a textile machine, and belongs to the field of textile machines. Compared with the prior art that a yarn and a clamp are in contactwith each other, so that relative sliding is caused, the yarn feeding flexible clamping device has the advantages that through the rotation of a clamp, the contact between a yarn and the clamp is converted from sliding friction to rolling friction, the relative sliding of the yarn and the clamp is greatly reduced, the possibility of generating yarn burrs is reduced, meanwhile, the yarn feeding condition is monitored in a real-time manner, data is collected by an image pick-up device, and is analyzed by a master console, the rotational speed of an electric motor is controlled by a controller, and when being fed, the yarn is always kept in the tightening state, so that on one hand, the possibility that the yarn is wound around the clamp can be reduced, on the other hand, the yarn feeding state is conveniently monitored in a real-time manner by workers, and the overall operation of the textile machine is beneficially controlled by the workers.

The invention discloses an antiskid permeable pavement which comprises a pavement base layer and an adhesive stone surface layer paved on the surface of the pavement base layer, the adhesive stone surface layer is prepared from the following raw materials in parts by weight: 2-5 parts of a component A, 3-7 parts of a component B and 95-105 parts of aggregate; the component A is prepared from the following raw materials: polyester of aliphatic dicarboxylic acids, polyether polyol, dipropylene glycol, neopentyl glycol, linoleic acid, castor oil, 2,2,3,3,4, 4,5,5-octafluoro-1-amyl alcohol, epoxyresin E-44, epoxy resin E-14, diphenyl-methane-diisocyanate, hexamethylene diisocyanate, nano silicon dioxide, nano calcium carbonate, boron carbide and modified lignin; the component B is prepared from the following raw materials: 1,8-diazacyclo[5,4,0]undecene-7 and triethanolamine. The anti-skid permeable pavement provided by the invention has the advantages of good skid resistance and water permeability, excellent aging resistance, short curing time and long service life.

The invention relates to the technical field of core tube beam columns, in particular to a core tube beam column structure for constructional engineering. The core tube beam column structure comprisesa frame, a cylinder, a pair of sliding rails, a pair of travelling cars, a pair of support seats, a fixing plate, two pairs of fixing brackets and a pair of support rods, wherein the cylinder is arranged in the frame; a pair of first grooves is formed in a side wall surface in the cylinder; the pair of sliding rails is arranged in the first grooves; the pair of travelling cars is arranged on thesliding rails; the pair of support seats is arranged on the pair of travelling cars; the fixing plate is arranged on the pair of support seats; a circular through hole is formed in the center of the fixing plate; and a plurality of rectangular through holes are formed in the fixing plate and in the outer side of the first circular through hole. According to the core tube beam column structure, theusing effect of the core tube beam column is improved, reasonable portioning arrangement of electric wires or cables is facilitated and the probability that multiple electric wires or cables are entwined with one another is reduced.

The invention relates to a protection guide device for a knee joint meniscus repair operation, relates to the technical field of medical instruments, and aims at solving the technical problem that an existing suture needle cannot smoothly and rapidly penetrate out of the body of a patient under guiding of a guiding device. The protective guide device comprises a guiding arc plate and a supporting annular plate, and the supporting annular plate is arranged at the end of the guiding arc plate and used for opening a minimally invasive incision. A partition plate is arranged on the side wall of the guide arc plate and divides the guide arc plate into a first penetrating area and a second penetrating area, the first penetrating area is used for penetrating of an endoscope, and the second penetrating area is used for penetrating of a suture needle. The device has the effect of guiding the suture needle to penetrate out of the body of a patient smoothly and quickly.

The invention relates to a laundry ball, in particular to an intelligent Internet-of-thing laundry ball. The laundry ball comprises a streamline-shaped laundry ball housing, the laundry ball housing is internally provided with a power supply module and a circuit board which is connected with the power supply module, the circuit board is provided with a control module, an RFID reading module, a washing parameter detection module and a wireless transmission module, the output ends of the RFID reading module and the washing parameter detecting module are connected with the control module, the wireless transmission module is in wireless connection with a mobile terminal APP or a server terminal, and the communication between the mobile terminal APP or the server terminal and the control moduleis achieved through the wireless transmission module. The laundry ball has the advantages of simple structure and convenient use, the laundry experience of a user can be improved, the washing effectis improved, and recognition can be conducted on clothes with an RFID label by a normal washing machine to allow the normal washing machine to achieve intelligence; recognition on the clothes in the laundry process can be conducted two or three times, and therefore the accuracy of clothes recognition is greatly improved.

The invention discloses a microbial agent particle drying device, and belongs to the technical field of drying. According to the scheme, the microbial agent particle drying device is sealed, high temperature generated by a heating rod is matched with an induced draft fan to sterilize and disinfect air in a drying chamber in advance, after the temperature is reduced to the room temperature, microbial agent particles are released into the drying chamber, then a cooling module is matched with the induced draft fan to generate cold air, the microbial agent particles are air-dried through an air outlet pipe and an exhaust hole, low temperature can accelerate dormancy of microorganisms, low-temperature airflow is matched with a water collecting column and a water condensing branch to enable moisture in the air to be condensed in time, and drying of the microbial agent particles is accelerated; and in addition, airflow is matched with disturbance balls and tying belts to swing and shake in the microbial agent particles, turning, stirring and crushing of the caked microbial agent particles are facilitated, and the drying efficiency is improved.

The invention relates to an agricultural machine and particularly relates to a vegetable seedling close planting machine. In a seed ribbon-based planting process, a seed ribbon cannot be quickly and easily unfolded from a wheel so that use is very inconvenient and the seed ribbon can be intertwined and knotted. The vegetable seedling close planting machine comprises reels, a reel rack and a locator. A seed ribbon enwinds the reel. The reel rack is used for installing and fixing the reel. The locator is used for fixing the initiating terminal of the seed ribbon. The reel rack comprises a support, a shaft lever and a pore plate. The front end of the support is provided with the pore plate. The reels are arranged on the reel rack in a single layer or multiple layers. The pore plate is detachable or is separated. The reel is provided with a damping device. The shaft lever is vertically arranged. Through use of the reels in a single layer or multiple layers, multi-ridge plantation and close planting seeding are realized and working efficiency is high. The damping device is arranged in the reel so that seed ribbon straightening and tightening are realized, seedlings are tidy and ribbon intertwining is reduced.

The invention discloses a yarn feeding flexible clamping device for a textile machine, and belongs to the field of textile machines. Compared with the prior art that a yarn and a clamp are in contactwith each other, so that relative sliding is caused, the yarn feeding flexible clamping device has the advantages that through the rotation of a clamp, the contact between a yarn and the clamp is converted from sliding friction to rolling friction, the relative sliding of the yarn and the clamp is greatly reduced, the possibility of generating yarn burrs is reduced, meanwhile, the yarn feeding condition is monitored in a real-time manner, data is collected by an image pick-up device, and is analyzed by a master console, the rotational speed of an electric motor is controlled by a controller, and when being fed, the yarn is always kept in the tightening state, so that on one hand, the possibility that the yarn is wound around the clamp can be reduced, on the other hand, the yarn feeding state is conveniently monitored in a real-time manner by workers, and the overall operation of the textile machine is beneficially controlled by the workers.

The invention relates to the technical field of wires and cables, in particular to a wire arranging device for high-voltage wires and cables for outdoor operation. The wire arranging device comprises a fixed seat, a fixed column, a sawtooth rod and a wire arranging assembly, a roller is arranged on the lower surface of the fixed seat, a winding drum is arranged on the right side of the upper surface of the fixed seat, a sliding groove is formed in the front end of the left side of the fixed seat, the fixed column is fixed to the right end of the sliding groove, a gear sleeves the upper end of the fixed column, the sawtooth rod is meshed and connected with the outer side of the gear, a clamping block is arranged at the outer side end of the middle of the sawtooth rod, the clamping block is fixed to a rod body of the fixed column, an electric telescopic rod is arranged at the left side end of the sawtooth rod, a circular ring is arranged below the clamping block, and the circular ring sleeves the rod body of the fixed column. The sawtooth rod can abut against the ends of the wires and the cables conveniently, winding is facilitated, and mutual winding of the wires and the cables is reduced through the wire arranging assembly.

The invention discloses a box girder spraying and life-preserving device, and relates to the technical field of bridge buildings. The device comprises a water supply unit and laying and drainage unitsarranged on the left side and the right side, the water supply unit comprises a movable trolley, the front side of the movable trolley is provided with a water supply pump, the water outlet end of the water supply pump communicates with a three-way pipe, the laying and drainage unit on the left side comprises a laying device and a drainage device, for the laying and drainage unit on the left side, the laying device comprises a winding shaft, the left side and the right side of the winding shaft are correspondingly, uniformly and fixedly connected with spoke supporting legs in the circumferential direction, the drainage device comprises a water spraying pipe, drainage strips are uniformly and fixedly connected to the left side of the water spraying pipe in the length direction, water spraying holes are uniformly formed in the right side of the water spraying pipe in the length direction, the head end of the water spraying pipe communicates with a branch pipe on the left side, and the tail end of the water spraying pipe is sealed; and the water spraying pipes on the left side and the right side are fixedly connected through a plurality of pull wires. The device has the beneficial effects that the drainage strips are used for realizing water spraying coverage, so that the waste of water is reduced, the utilization rate of the water is improved, and the life-preserving effect is improved.

The invention relates to an electric power engineering pipeline and a construction method thereof in the field of electric power engineering, and aims to solve the problem of improving the efficiencyof finding a required cable during maintenance, the electric power engineering pipeline comprises a plurality of sections of outer pipes, a plurality of groups of inner pipes and a plurality of connecting pieces, the outer pipes are connected end to end, each section of outer pipe is internally provided with a group of inner pipes, each group of inner pipes comprises multiple inner pipes, the inner pipes are fixed in the outer pipes, and the inner pipes in every two adjacent outer pipes are connected to the end sides close to each other through the connecting pieces. The electric power engineering pipeline has the advantages that the situation that cables are wound in the electric power engineering pipeline is reduced, and the efficiency of finding the needed cables is improved.

A split type portable ultrasonic scalpel comprises a power source assembly, a winder connected with the power source assembly, a grip transducer assembly connected with the other end of the winder and a detachable scalpel head assembly arranged on the front portion of the grip transducer assembly. Electric energy is output through the power supply assembly, is output to an ultrasonic transducer in the grip transducer assembly through the winder, is converted into high-frequency mechanical vibration through the ultrasonic transducer, is output to the tool bit working part through the conduction shaft rod to generate high-frequency ultrasonic vibration, and is used for adjusting the frequency of an output signal according to a clamped tissue and output feedback so as to achieve the optimal efficiency; the split type design is adopted, so that the arm burden of an operator is relieved; compared with a traditional ultrasonic scalpel, the ultrasonic scalpel has the advantages that the overall size and weight of the system are greatly reduced, and meanwhile, the weight of a handheld part is not increased; the system disclosed by the invention is reasonable in mass distribution and relatively high in use portability, comfort and controllability.

The invention discloses a pulsator washing machine with a washing ball disc, comprising a water containing drum, an outer case body, a water inlet, a water drainage pipe, a washing drum, an upper cover, a control panel, a motor, a reducer, a transmission belt, and a pulsator. The washing drum is internally equipped with a washing ball disc which comprises a plurality of washing balls, a disc frame, and fixing members. The washing balls are mounted in disc holes of the disc frame. The fixing members are arranged at the periphery of the disc frame. The inner wall of the washing drum is provided with grooves, and a buckle is arranged above each groove in one side. The fixing members are installed in the grooves, and the buckles buckle and fix one side of each fixing member. Cloth intertwining is reduced, the cleanness is improved, the washing time is reduced, and electricity and water are saved.

The invention discloses an assembled multifunctional cabinet, and relates to the technical field of cabinets. The cabinet comprises a cabinet body, an even water groove is formed in the upper surfaceof the cabinet body; a water pipe fixedly communicates with the upper surface of the cabinet body; the side wall of the cabinet body is fixedly connected with a storage plate. The upper surface of thestorage plate is fixedly connected with a fixed plate; a garbage can is arranged on the upper surface of the shelf; the side wall of the fixing plate is slidably connected with a sliding column. Thesliding column penetrates through one side wall of the fixed plate and is fixedly connected with a pressing plate; the pressing plate contacts the side wall of the garbage can; the outer surface of the sliding column is sleeved with a reset spring, a through groove is formed in the front end face of the cabinet body, a drawer box is slidably connected into the through groove, a groove is formed inthe side wall of the drawer box, a clamping column is slidably connected into the groove, a clamping hole is formed in the side wall of the cabinet body, the clamping column penetrates through the clamping hole and is slidably connected with the clamping hole, and a telescopic spring is arranged in the groove. The problems that an existing cabinet is single in function, and a drawer box of the cabinet is not limited and is prone to falling off are solved.

The invention relates to a folding method of a regular polygonal rope net, which is especially suitable for large-scale rope nets. Folding; step 2, wrap N side strings in M ​​side string bags respectively, N=M; step 3, extend the center knot of the rope net into the net bag, lower the rope net, gradually Stow the rope net into the net bag; step 4, fix the M side line rope bags on the outer surface of the outermost net bag to complete the folding and storage of the rope net. The invention solves the problems that when the area of ​​the rope net is too large, the shape of the net is messy and it is inconvenient to fold;

The invention provides a taking-out device which is used for taking out a slender structure implanted in a body. The taking-out device comprises a control handle, a sheath tube connected to the far end of the control handle and an expansion head connected to the far end of the sheath tube, wherein the control handle comprises a driving piece and a rotating piece, one end of the rotating piece is connected with the near end of the sheath tube, the other end of the rotating piece is connected with the driving piece, and the driving piece is used for driving the rotating piece to rotate in two directions so as to drive the sheath tube and the expansion head to rotate in two directions. The expansion head can effectively cut fiber tissue wrapping the periphery of the slender structure, and other wires in a blood vessel can be prevented from being wound with one another and the situation that the blood vessel wall is twisted and scratched by the expansion head is prevented.

The invention provides a preparation method of a coating dispersant and the coating dispersant prepared by the method. The preparation method comprises the following steps: synthesizing polyether alcohol and a cyclic monomer into polyether under the action of a catalyst; reacting the polyether with an acid substance under the action of a reducing agent, an initiator and a chain transfer agent to prepare a polyether dispersant; and adding a neutralizer into the polyether dispersant to prepare the coating dispersant, wherein on the basis that the total amount of the raw materials is 1000 parts by mass, the use amounts of the raw materials are as follows: 79.29 to 83.57 parts by mass of the polyether alcohol ether, 160.97 to 169.68 parts by mass of the cyclic monomer, 0.7 to 1.9 parts by mass of the catalyst, 129.74 to 136.75 parts by mass of the acid substance, 2.1 to 4.5 parts by mass of the reducing agent, 3.9 to 6.7 parts by mass of the initiator, 0.6 to 3.0 parts by mass of the chain transfer agent, 7.1 to 12.8 parts by mass of the neutralizing agent and the balance of water; the polyether alcohol head is trans-4, 4-dimethoxy-2-butenol, the cyclic monomer is ethylene oxide and propylene oxide, and the acid substance is acrylic acid.

The invention relates to polyester polyol with a special structure, in particular to polyester polyol for synthesizing moisture cured polyurethane hot melt adhesives. The polyester polyol is prepared from three kinds of monomers A, B and C through esterification reaction, wherein the A is at least one kind of long straight chain binary acid, and the long straight chain binary acid refers to straight chain binary acid containing eight carbon atoms or above in the carbon chains; the B is at least one kind of long straight chain dihydric alcohol, and the long straight chain dihydric alcohol refers to the straight chain dihydric alcohol containing five carbon atoms or above in the carbon chain; the C is at least one kind of long branch chain dihydric alcohol, the long branch chain dihydric alcohol refers to dihydric alcohol with linear straight carbon chain and at least one long branch chain structure, and the long branch chain structure refers to carbon chains containing two methylene or above. The synthesized polyester polyol has the advantages of high molecular weight and low normal temperature viscosity. When the polyester polyol provided by the invention is used, the polyurethane hot melt adhesives with low melt viscosity can be generated through the reaction with isocyanate on the premise of not increasing the content of the isocyanate.