Device and method for preparing quick-drying polyolefin hot melt adhesive

Abstract

The invention discloses a preparation device and method of a quick-drying polyolefin hot melt adhesive. The preparation device comprises a rack, and a premixing module, a main material conveying module, a reaction synthesis module and a liquid phase metering and adding system which are arranged on the rack, the pre-mixing module comprises a pre-mixing feeding hopper and a pre-mixing bin located above the pre-mixing feeding hopper, the bottom of the pre-mixing bin is communicated with the pre-mixing feeding hopper through a discharging valve, a weighing module is arranged at the bottom of the pre-mixing feeding hopper and fixedly connected with the rack through a weighing sensor support, and a pre-mixing stirring mechanism is arranged in the pre-mixing bin; the main material conveying module comprises a feeding auger, the feeding end of the feeding auger is connected with the premixing feeding hopper through a discharging valve, and the discharging end of the feeding auger is communicated with the reaction synthesis module; through an automatic device integrated with a central control system and an optimized preparation process, accurate metering, coordinated regulation and segmented treatment in the hot melt adhesive production process are realized, and the product consistency and the production efficiency are effectively improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of high polymer material preparation, in particular to a preparation device and method of quick-drying polyolefin hot melt adhesive. BACKGROUND

[0002] The hot melt adhesive is a thermoplastic adhesive coated in a molten state, and the adhesive is formed after cooling; the polyolefin hot melt adhesive is widely applied due to low price, non-toxicity and non-odor; however, the traditional polyolefin hot melt adhesive has problems of slow drying speed and insufficient initial adhesion, which limits the application of the polyolefin hot melt adhesive in some high-speed automatic production lines.

[0003] There are two core problems in the preparation of the existing quick-drying polyolefin hot melt adhesive: in the preparation device, the premixing link lacks precise metering and dust collection design, resulting in deviation of raw material ratio and environmental pollution; each module has no unified central control system linkage, and the automation and collaboration are low, for example, the main material conveying and additive adding cannot match the material state; the reaction kettle temperature control and stirring design are single and lack an efficient vacuum system, which is difficult to meet the segmented melting demand and is prone to mixed dead angles and product bubbles. In the preparation method, the one-step heating for melting and mixing easily causes uneven melting of the material, the dehydration link does not realize the vacuum and high-speed dispersion collaboration, and the water removal efficiency is low; the photocuring component and crystallization additive are added at one time and have no parameterized triggering mechanism, and are prone to failure or uneven dispersion; the product toughness is reduced by improving the quick-drying performance through a single means, and the consistency of different batches of products is poor due to the device and process problems.

[0004] Therefore, the application provides a preparation device and method of quick-drying polyolefin hot melt adhesive to solve the above problems. SUMMARY

[0005] The application aims to provide a preparation device and method of quick-drying polyolefin hot melt adhesive to solve the problems of inaccurate premixing metering, dust pollution, no unified central control linkage of modules, and difficulty in meeting the segmented melting demand of the reaction kettle design in the existing preparation device of quick-drying polyolefin hot melt adhesive, and the problems of uneven melting, low dehydration efficiency, failure or uneven dispersion of components, reduction of toughness due to improvement of quick-drying performance, and poor consistency of batches in the existing preparation method of quick-drying polyolefin hot melt adhesive.

[0006] To achieve the above object, the application provides the following technical scheme: a preparation device of quick-drying polyolefin hot melt adhesive, comprising a rack, and a premixing module, a main material conveying module, a reaction synthesis module and a liquid phase metering and adding system arranged on the rack. The premixing module comprises a premix feeding hopper and a premix bin located above the premix feeding hopper, the bottom of the premix bin is communicated with the premix feeding hopper through a discharging valve, the bottom of the premix feeding hopper is provided with a weighing module, the weighing module is fixedly connected with the rack through a weighing sensor support, and a premix stirring mechanism is arranged in the premix bin. The main material conveying module comprises a feeding auger, the feeding end of the feeding auger is connected with the premix feeding hopper through a discharging valve, and the discharging end of the feeding auger is communicated with the reaction synthesis module. The reaction synthesis module comprises a reaction kettle and a stirring mechanism, the stirring mechanism is driven by a linear module arranged on the rack to move up and down, and the reaction kettle is a jacketed structure and is electrically connected with a temperature control system. The liquid phase metering and adding system comprises an additive storage tank and a metering liquid adding system, the metering liquid adding system is communicated with the reaction kettle through a conveying pipeline. The device further comprises a vacuum system communicated with the reaction kettle. The premixing module, the main material conveying module, the reaction synthesis module, the liquid phase metering and adding system, the temperature control system and the vacuum system are all controlled by a central control system.

[0007] Preferably, the top of the premix bin of the premixing module is provided with a bin cover, the bin cover is driven to open and close by a motorized push rod symmetrically mounted on the top of the premix bin, and the output end of the motorized push rod is rotationally connected with the bin cover.

[0008] Preferably, the premix stirring mechanism comprises a premix stirring motor and a premix stirring paddle driven by the premix stirring motor, and one side of the premix feeding hopper is connected with a dust collector through a pipeline.

[0009] Preferably, the feeding auger of the main material conveying module is internally provided with a spiral blade, the spiral blade is driven by a conveying motor, and the bottom of the feeding auger is connected with the rack through a guide support assembly.

[0010] Preferably, the stirring mechanism of the reaction synthesis module comprises a main stirring motor and a stirrer, the main stirring motor is mounted on the output end of the linear module, the reaction kettle is fixed on the rack through a clamping assembly, and the top of the reaction kettle is fixedly connected with a kettle cover.

[0011] Preferably, the metering liquid adding system comprises a metering pump, a flow meter and a control valve.

[0012] Preferably, the temperature control system comprises a heat conducting oil circulating unit flowing through the jacket of the reaction kettle.

[0013] The application also discloses a preparation method of the quick-drying polyolefin hot melt adhesive. S1, raw material preparation: provide polyolefin matrix, tackifying resin, viscosity modifier, antioxidant, light curing component and crystallization aid; wherein the light curing component includes a photoinitiator and a polymer containing a photo-crosslinkable functional group; the crystallization aid includes a high crystallinity polyolefin and a nucleating agent; S2, pre-mixing and program setting: the polyolefin matrix, tackifying resin, viscosity modifier and antioxidant are put into the pre-mixing module for preliminary mixing to obtain a pre-mixed solid raw material; at the same time, the liquid additive is put into the liquid phase metering system; the preparation program including the temperature rising curve, the stirring rate curve, the vacuum degree curve and the additive addition trigger point is set in the central control system; the liquid additive at least contains the light curing component; S3, initialization and feeding: start the device, control the temperature control system to preheat the reaction kettle to 100-140℃ through the central control system; then the pre-mixed solid raw material is transported into the reaction kettle through the main material conveying module; S4, stepwise melting and mixing: the central control system controls the temperature control system to heat the material to the final temperature of 160-220℃ according to the set temperature rising curve, and controls the stirring mechanism to operate according to the set stirring rate curve, so that the material is melted and mixed; S5, vacuum dewatering and fine dispersion: when the material is completely melted and the temperature reaches the set value, the central control system starts the vacuum system to vacuumize the reaction kettle, reduces the pressure to below-0.08MPa and maintains for 10-60 minutes; at the same time, the stirring mechanism is controlled to improve the speed to the high-speed dispersion mode; S6, trigger additive: when the system parameters reach the pre-set additive addition trigger point, the central control system instructs the liquid phase metering system to add the liquid additive to the reaction kettle; S7, homogenization and discharge: after the additive addition is completed, the central control system adjusts the stirring mechanism for 10-30 minutes of homogenization stirring, while maintaining the temperature and vacuum degree; finally, the vacuum is released and the product is discharged.

[0014] Preferably, the sum of the weight fraction of the light curing component and the crystallization aid accounts for 5% to 50% of the total weight of the hot melt adhesive, the polymer containing a photo-crosslinkable functional group is selected from at least one of the polyolefin modified polymers having (meth)acrylate functional group, allyl functional group, thiol-olefin system, or silane functional group, the high crystallinity polyolefin is selected from at least one of linear low density polyethylene (LLDPE), high density polyethylene (HDPE), isotactic polypropylene (iPP), isotactic polybutylene (iPB), and the nucleating agent is selected from at least one of sorbitol derivatives, organic carboxylate, organic phosphate, talc, calcium carbonate.

[0015] Preferably, in step S6, the preset additive addition trigger point is when the system viscosity reaches 500-2000 cP.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: This apparatus and method for preparing quick-drying polyolefin hot melt adhesive, through the integration of an automated device with a central control system and optimized preparation process, achieves precise metering, coordinated control, and segmented processing during the hot melt adhesive production process, effectively improving product consistency, quality, and production efficiency. The specific details are as follows: Firstly, in the premixing module, the weighing module at the bottom of the premixing hopper uses a weighing sensor to accurately measure the weight of raw materials, solving the problem of inaccurate proportions caused by measurement deviations in traditional premixing. Simultaneously, the dust collector connected to the hopper can collect premixed dust in a timely manner, avoiding raw material waste and environmental pollution, and improving the cleanliness of the production environment. Furthermore, the device uses a central control system to uniformly control six modules: premixing, main material conveying, reaction synthesis, liquid phase metering and addition, temperature control, and vacuum. Based on the material's temperature, viscosity, and other conditions, it can automatically adjust the main material conveying rate, the timing of additive addition, stirring parameters, and vacuum level, solving the problem of independent operation and poor coordination among modules in traditional devices, improving the level of production automation and reducing human error. In the reaction synthesis module, the jacketed reactor, combined with a temperature control system, can precisely raise the temperature in stages to meet the temperature requirements of different melting stages of the materials. The stirring mechanism is driven by a linear module to achieve lifting and lowering, adapting to the stirring needs of different liquid levels in the reactor to eliminate mixing dead zones and improve material uniformity. The high-efficiency vacuum system can also quickly reduce the pressure inside the reactor to below -0.08MPa, reducing product bubbles and residual moisture, and solving the shortcomings of traditional reactors such as single temperature control, insufficient stirring, and poor vacuum effect. The liquid phase metering and addition system realizes the quantitative delivery of liquid additives through metering pumps, flow meters, and control valves. Combined with the parameterized triggering mechanism of the central control system (such as viscosity trigger point), the additives are precisely added when the materials are in the optimal state, avoiding the quantity difference and timing deviation of traditional manual addition.

[0017] Secondly, by optimizing the details of the preparation method, the material processing effect and the value of the additives are further improved. A segmented heating curve combined with a stirring rate curve is adopted to replace the traditional one-step heating method. This allows solid raw materials such as the polyolefin matrix and tackifying resin to gradually melt at different temperature stages. Combined with an appropriate stirring rate, local overheating or incomplete melting is avoided, improving the uniformity of material melting. In the vacuum dehydration stage, the central control system links the vacuum system and the stirring mechanism. While drawing a vacuum, the stirring speed is increased to a high-speed dispersion mode, allowing the material to fully tumble under negative pressure. This accelerates moisture evaporation and promotes the microparticle dispersion of the material, solving the problems of low dehydration efficiency and insufficient dispersion in traditional methods. Meanwhile, preset additive addition trigger points (such as system viscosity 500-2000 cP) ensure that liquid additives such as photocurable components and crystallization aids are added when the material is in the best molten state and the viscosity is suitable, avoiding premature failure or uneven dispersion of additives caused by traditional one-time addition; and the photocurable components and crystallization aids work synergistically to improve the quick-drying performance of hot melt adhesives, while balancing the toughness of the product through functional group crosslinking and crystallization regulation, overcoming the problem of reduced toughness caused by single quick-drying improvement.

[0018] Finally, by optimizing the equipment and improving the methods throughout the entire process, we achieve a comprehensive improvement in product batch consistency and overall quality. The central control system precisely controls parameters such as heating, stirring, vacuum, and additive addition throughout the entire process, reducing parameter fluctuations caused by human intervention. This ensures that key indicators such as raw material ratios, melt state, and additive dispersion remain stable across different batches, thereby improving product batch consistency. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 For the present invention Figure 1 Another perspective structural diagram; Figure 3 This is a schematic diagram of the internal structure of the frame in this invention; Figure 4 For the present invention Figure 4 Another perspective structural diagram; Figure 5 This is a schematic cross-sectional view of the feeding auger and the reaction vessel in this invention; Figure 6 This is a three-dimensional structural diagram of the premixing chamber in this invention; Figure 7 This is a three-dimensional structural diagram of the premixed stirring blade in this invention.

[0020] In the diagram: 1. Frame; 2. Premixing module; 201. Weighing sensor bracket; 202. Weighing module; 203. Premixing hopper; 204. Dust collector; 205. Premixing bin; 206. Electric push rod; 207. Bin cover; 208. Premixing stirring motor; 209. Premixing stirring blade; 3. Main material conveying module; 301. Feeding auger; 302. Conveying motor; 303. Spiral blade; 304. Guide support assembly; 4. Reaction synthesis module; 401. Reactor; 402. Reactor cover; 403. Linear module; 404. Main stirring motor; 405. Stirrer; 406. Clamping assembly; 5. Liquid phase metering and adding system; 501. Additive storage tank; 502. Metering and adding system; 6. Temperature control system; 7. Central control system. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Please see Figures 1-7 This invention provides a technical solution: a device and method for preparing quick-drying polyolefin hot melt adhesive. By integrating functional modules such as premixing, precise delivery, reaction synthesis, metering addition, and intelligent control, the device achieves automated and continuous preparation of hot melt adhesive, effectively improving product quality stability and production efficiency. The core structure of the device includes a frame 1 and mounted on it a premixing module 2, a main material delivery module 3, a reaction synthesis module 4, a liquid phase metering addition system 5, a temperature control system 6, a vacuum system, and a central control system 7. These modules work together to complete the hot melt adhesive preparation process.

[0023] The frame 1 is welded from Q235 carbon steel. The layout of each module on the frame 1 follows the principle of "smooth material flow and convenient operation and maintenance": the premixing module 2 is located on the upper left side of the frame, the main material conveying module 3 is inclined between the premixing module 2 and the reaction synthesis module 4, the reaction synthesis module 4 is located in the middle of the frame, the liquid phase metering and adding system 5 is located on the right side of the frame, and the temperature control system 6 and the vacuum system are located at the bottom of the frame.

[0024] Premixed bin 205: Made of 304 stainless steel, the top cover 207 is an arc-shaped structure of the same material, with a diameter matching the bin opening, and a silicone sealing ring on the edge (temperature resistant to 200℃ to ensure a tight seal).

[0025] Electric actuator 206: The electric actuator is model DT300, with a rated thrust of 3000N, a stroke of 200mm, and a voltage of 220V. It is symmetrically installed on both sides of the top of the premixing chamber 205. The output end is rotatably connected to the ear plate on the side of the chamber cover 207 through a pin. The opening and closing time is controlled at 10-15s to avoid dust leakage.

[0026] Premixing mechanism: The premixing motor 208 is a Y132S-4 type three-phase asynchronous motor (power 5.5kW, speed 1440rpm), which is connected to the premixing impeller 209 through a reducer (reduction ratio 1:5); the impeller has a double-layer spiral ribbon structure and is made of 304 stainless steel to ensure that the material mixing uniformity is ≥95%.

[0027] Premixed feeding hopper 203: Made of 304 stainless steel, with a pneumatic discharge valve (model Q641F-16P, diameter DN100) at the bottom to control the discharge speed of 50-100kg / h; one side is connected to dust collector 204 through a DN50 304 stainless steel pipe. The dust collector is a pulse bag dust collector (handling air volume of 1000m³ / h, filtration accuracy of 1μm) to prevent dust from escaping during feeding.

[0028] Weighing module 202: Three ZEMICH8C type weighing sensors (range 500kg, accuracy 0.1%FS) are selected and evenly fixed between the frame 1 and the premixed feeding hopper 203 through the weighing sensor bracket 201 (304 stainless steel material). The real-time weighing error is ≤±0.5kg and the data is transmitted to the central control system 7.

[0029] Feeding auger 301: Made of 304 stainless steel, the internal spiral blades 303 are continuous spirals, made of 304 stainless steel, and the surface is polished (roughness Ra≤0.8μm) to reduce material residue.

[0030] Conveyor motor 302: Selects Y100L-4 type three-phase asynchronous motor (power 3kW, speed 1440rpm), connected to the shaft of spiral blade 303 through a coupling, equipped with frequency converter (model VFD037M43B), which can realize speed adjustment from 50-300rpm, corresponding to conveying capacity of 20-100kg / h.

[0031] Guide support assembly 304: includes rollers and guide rails to ensure that the auger can rotate, so that the output end of the feeding auger 301 can be separated from the reactor 401 as needed.

[0032] Reactor 401: Made of 316L stainless steel, the jacket has a semi-pipe winding structure, which can realize uniform flow of heat transfer oil and temperature control accuracy of ±1℃.

[0033] The vessel lid is made of 316L stainless steel and is connected to the vessel opening via a flange (flange specification DN1200, pressure rating 1.6MPa). It is equipped with a silicone gasket (temperature resistance 250℃). The vessel lid has a pre-reserved feed port (DN100, which connects to the discharge end of the feeding auger 301), an additive addition port (DN50, which connects to the liquid phase metering addition system 5), a vacuum interface (DN80), a temperature sensor interface (PT100), and a viscosity sensor interface (model VT-100).

[0034] Stirring mechanism: The main stirring motor 404 is a Y200L-4 type three-phase asynchronous motor (power 15kW, speed 1470rpm), which is connected to the stirrer 405 through a planetary reducer (reduction ratio 1:20); the stirrer has a three-layer blade structure (upper layer is paddle type, middle layer is anchor type, lower layer is turbine type), made of 316L stainless steel, with an outer diameter of 1180mm, to ensure that there are no dead corners in the stirring of materials; the linear module 403 is a ball screw type linear slide (stroke 500mm, rated load 500kg, positioning accuracy ±0.1mm), which drives the stirring mechanism to lift and lower, facilitating cleaning and maintenance inside the vessel (lifting speed 50mm / s).

[0035] Clamping assembly 406: includes two sets of arc-shaped clamps (made of 316L stainless steel), symmetrically installed in the middle of the frame 1, which can firmly fix the reactor 401.

[0036] Additive storage tank 501: Made of 304 stainless steel (200L / unit), it stores light-curing components and other liquid additives. The tank wall is equipped with a level gauge (magnetic float level gauge, range 0-200L), a temperature sensor (to control the temperature inside the tank at 25±5℃), and a stirring device (small paddle stirrer, speed 100rpm, to prevent additives from separating).

[0037] Metering and dispensing system 502: A plunger-type metering pump (model JZ plunger pump, flow rate 0-50L / h, accuracy ±0.5%) is selected. The outlet of the metering pump is connected in sequence to an electromagnetic flow meter (model LDG-50, accuracy ±0.2%) and a pneumatic ball valve (model Q641F-16P, diameter DN25). The delivery pipeline is made of 304 stainless steel pipe (diameter DN25, wall thickness 2mm), and a pressure gauge (range 0-1MPa) is installed on the pipeline to ensure accurate addition of additives.

[0038] Temperature control system 6: The system adopts a heat transfer oil circulation temperature control method, using L-QC320 synthetic heat transfer oil (applicable temperature range: -20℃ to 320℃). The system includes an electric heating furnace (30kW power, adjustable heating power), a circulation pump (flow rate 50m³ / h, head 20m), an expansion tank, and a cooler (plate heat exchanger, heat exchange area 10㎡). The temperature of the material inside the reactor 401 and the temperature of the jacketed heat transfer oil are collected in real time by a PT100 temperature sensor. The central control system 7 controls the start and stop of the heating furnace and cooler to achieve a temperature control range of 50-250℃ and a temperature control accuracy of ±1℃.

[0039] Vacuum system: Composed of a Roots vacuum pump (model ZJ-150, ultimate vacuum -0.098MPa, pumping speed 150L / s) and a backing mechanical vacuum pump (model 2X-70A, ultimate vacuum 0.001MPa), both connected to the vacuum port of reactor 401 via 304 stainless steel pipe (diameter DN80); the pipe is equipped with a vacuum valve (butterfly valve, model D371F-16P), a vacuum pressure gauge (range -0.1-0MPa, accuracy ±0.4%), and a check valve (to prevent backflow); the system can reduce the pressure inside reactor 401 to below -0.09MPa within 5 minutes, meeting the requirements for vacuum dehydration.

[0040] Central Control System 7: The core hardware is a Siemens S7-1200 series PLC (model 1214CDC / DC / DC), equipped with a 10-inch touch screen (model KTP1000Basic), which can display the operating parameters of each module (temperature, pressure, speed, weight, flow, etc.) in real time, and supports parameter setting, program storage (can store 100 sets of different process programs) and fault alarms (such as over-temperature, over-pressure, motor overload, etc., alarm mode is audible and visual alarm); the system connects to each motor, metering pump and sensor through Modbus communication protocol to realize fully automated control, and can also be switched to manual mode for debugging and emergency operation.

[0041] This embodiment is based on claims 8-10, and uses the above-mentioned apparatus to prepare quick-drying polyolefin hot melt adhesive. The detailed steps are as follows: all raw materials are commercially available industrial-grade products, and the process parameters have been optimized multiple times to ensure stable product performance.

[0042] Step S1: Raw material preparation (taking 100kg of hot melt adhesive as an example) Prepare raw materials according to the following weight proportions. All solid raw materials should be crushed to a particle size ≤2mm (to avoid clogging the feed auger). Liquid raw materials should be filtered through a 0.45μm filter membrane (to remove impurities): Polyolefin matrix: 50 parts, homopolymer polypropylene (PP, model H-T36F, melt flow rate 15g / 10min (230℃, 2.16kg), density 0.91g / cm³). Tackifying resin: 20 parts, C5 petroleum resin (model T-105, softening point 105±5℃, acid value ≤1mgKOH / g). Viscosity modifier: 5 parts, made of fully refined paraffin wax (model 58#, melting point 58-60℃, penetration 20-25dmm (25℃)). Antioxidant: 1 part, which is a compound of antioxidant 1010 (0.6 parts) and antioxidant 168 (0.4 parts) (both are commercially available industrial grade). Photocurable components: 15 parts, including photoinitiator (2 parts, model 1173, 2-hydroxy-2-methyl-1-phenyl-1-propanone) and acrylate-modified polyolefin (13 parts, model PAO-300, 100% solid content, viscosity 800 cP (25℃)). Crystallization aid: 9 parts, including high-density polyethylene (HDPE, 7 parts, model 5000S, melt flow rate 0.9g / 10min (190℃, 2.16kg)) and nucleating agent (2 parts, model Millad3988, sorbitol derivative).

[0043] Step S2: Premixing and Program Setting Premixing operation: The electric push rod 206 is controlled by the central control system 7 to open the cover 207 of the premixing chamber 205, and the above-mentioned polyolefin matrix, tackifying resin, viscosity modifier and antioxidant (total 76kg) are put into the premixing chamber 205. Close the silo cover 207, start the premixing motor 208, set the speed to 300 rpm, and mix for 10 minutes (turn on the dust collector 204 during the mixing process to prevent dust from escaping); after the mixing is finished, open the bottom discharge valve of the premixing silo 205 and discharge the premixed solid raw material into the premixing feed hopper 203. The weighing module 202 confirms that the weight of the raw material is 76 kg (error ±0.5 kg, alarm will be triggered if the deviation exceeds the range).

[0044] Liquid additives addition: Add the photocurable component (15 kg) into the auxiliary agent storage tank 501 of the liquid phase metering addition system 5, start the stirring device in the storage tank (speed 100 rpm), maintain the temperature at 25°C, and prevent stratification.

[0045] Program settings: Call up or create a new process program on the touchscreen of the central control system 7, and set the parameters as follows: Heating curve: 100℃ (preheating) → 140℃ (heating rate 5℃ / min, hold for 15min) → 160℃ (heating rate 2℃ / min, hold for 20min) → 200℃ (heating rate 1℃ / min, hold for 30min). Stirring rate curve: initial 200 rpm (100-140℃) → 300 rpm (140-160℃) → 400 rpm (160-200℃) → 600 rpm (vacuum dehydration stage) → 500 rpm (homogenization stage); Vacuum degree curve: After the vacuum system is started, it drops to -0.095MPa within 5 minutes and is maintained for 40 minutes; Additive addition trigger point: The system viscosity reaches 1000 cP (monitored in real time by the viscosity sensor on the reactor lid 402).

[0046] Step S3: Initialization and Feeding Device initialization: Start the central control system 7, check the status of each module (whether the motor, valve, and sensor are normal), and confirm that there is no residual material in the reactor 401 and that the reactor lid 402 is well sealed. Start the temperature control system 6 and preheat the reactor 401 to 100°C according to the set heating curve for 30 minutes (to ensure uniform temperature inside the reactor and avoid local overheating of the raw materials). During this period, the temperature inside the reactor is monitored in real time by the temperature sensor. If the deviation exceeds ±2°C, the system will automatically adjust.

[0047] Premixed solid feedstock feeding: After preheating, the central control system 7 automatically opens the bottom discharge valve of the premixed feeding hopper 203 and the conveying motor 302 of the feeding auger 301, sets the feeding auger speed to 150 rpm (conveying capacity 50 kg / h), and conveys 76 kg of premixed solid raw materials into the reactor 401. During the conveying process, the weighing module 202 provides real-time feedback on the remaining weight. When the weight drops to 0kg, the system automatically closes the unloading valve and the conveying motor 302, completing the feeding (conveying time is approximately 90s).

[0048] Step S4: Segmented melting and mixing After the feeding is completed, the central control system 7 controls the temperature control system 6 to heat according to the set heating curve, and at the same time starts the stirring mechanism of the reaction synthesis module 4 (initial speed 200 rpm). When the temperature rises to 140℃ (about 30 minutes later), the system automatically increases the stirring speed to 300 rpm and maintains it for 15 minutes (to ensure that the solid raw materials are initially melted and there is no obvious clumping). Continue heating to 160℃ (after about 40 minutes), increase the stirring speed to 400 rpm and maintain for 20 minutes (the raw material further melts and forms a homogeneous melt). Finally, raise the temperature to 200℃ (after about 50 minutes) and maintain it for 30 minutes. During this period, observe the material state through the observation window of the lid 402 (if present) to ensure that there are no unmelted particles (the molten state is a transparent and homogeneous liquid).

[0049] Step S5: Vacuum dehydration and fine dispersion When the material is completely melted and the temperature is stable at 200℃, the central control system 7 automatically starts the vacuum system, opens the vacuum valve, and reduces the pressure in the reactor 401 to -0.095MPa within 5 minutes, and maintains it for 40 minutes. Meanwhile, the system increases the stirring speed to 600 rpm (high-speed dispersion mode), and removes trace amounts of moisture (moisture content reduced to below 0.1%) and small molecule volatiles (such as low-boiling components of paraffin) from the melt through the shearing action of the turbine blades. During this process, the vacuum pressure gauge displays the pressure in real time. If the pressure rises above -0.09 MPa, the system automatically increases the power of the vacuum pump.

[0050] Step S6: Trigger the addition of adjuvants During the vacuum dehydration process, the viscosity sensor on the lid 402 monitors the viscosity of the system in real time. When the viscosity reaches the set trigger point (1000 cP), the central control system 7 automatically commands the liquid phase metering and adding system 5 to start. The metering pump pumps 15 kg of photocurable component into reactor 401 through the additive addition port at a set flow rate (1.5 L / min). During the addition process, the temperature is maintained at 200℃ and the stirring speed is 600 rpm. The electromagnetic flow meter provides real-time feedback on the amount added. When the amount added reaches 15 kg, the system automatically shuts off the metering pump and the pneumatic ball valve to complete the additive addition (addition time is about 10 min).

[0051] Step S7: Homogenization and Discharge After the additives are added, the central control system 7 adjusts the stirring speed to 500 rpm and performs homogenization stirring for 20 minutes (to ensure that the photocurable components are completely mixed with the melt and there is no local agglomeration), during which the temperature is maintained at 200℃ and the vacuum degree is -0.095MPa. After homogenization, the system first shuts off the vacuum system and slowly opens the venting valve (to introduce nitrogen gas to prevent air from entering and causing oxidation). After the pressure inside the reactor 401 returns to normal pressure, the bottom discharge valve (model Q641F-16P, diameter DN100) is opened, and the linear module 403 is started to lift the stirring mechanism (to prevent the blades from scraping the bottom of the reactor). The product flows through the discharge valve into a storage tank (made of 304 stainless steel) preheated to 180°C. During the discharge process, the temperature inside the reactor is maintained at 180-200°C to prevent the product from cooling, solidifying, and clogging the pipes. After discharge, the system automatically activates the temperature control system 6 to cool the reactor. Once the temperature of reactor 401 drops below 80°C, the reactor lid 402 can be opened for cleaning, preparing for the next batch of production. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A device for preparing a quick-drying polyolefin hot melt adhesive, comprising a rack (1), a premixing module (2), a main material conveying module (3), a reaction and synthesis module (4), and a liquid phase metering and adding system (5) arranged on the rack (1), characterized in that: the premixing module (2) comprises a premixing feeding hopper (203) and a premixing bin (205) arranged above the premixing feeding hopper (203), the bottom of the premixing bin (205) is communicated with the premixing feeding hopper (203) through a discharging valve, the bottom of the premixing feeding hopper (203) is provided with a weighing module (202), the weighing module (202) is fixedly connected with the rack (1) through a weighing sensor support (201), and a premixing stirring mechanism is arranged in the premixing bin (205); the main material conveying module (3) comprises a feeding auger (301), the feeding end of the feeding auger (301) is connected with the premixing feeding hopper (203) through a discharging valve, and the discharging end of the feeding auger (301) is communicated with the reaction and synthesis module (4); the reaction and synthesis module (4) comprises a reaction kettle (401) and a stirring mechanism, the stirring mechanism is driven by a linear module (403) arranged on the rack (1) to move up and down, and the reaction kettle (401) is a jacketed structure and is electrically connected with a temperature control system (6); the liquid phase metering and adding system (5) comprises an additive storage tank (501) and a metering and liquid adding system (502), and the metering and liquid adding system (502) is communicated with the reaction kettle (401) through a conveying pipeline; the device further comprises a vacuum system communicated with the reaction kettle (401); and the premixing module (2), the main material conveying module (3), the reaction and synthesis module (4), the liquid phase metering and adding system (5), the temperature control system (6), and the vacuum system are all controlled by a central control system (7). A bin cover (207) is arranged on the top of the premixing bin (205) of the premixing module (2), the bin cover (207) is driven to open and close by a pair of electric push rods (206) symmetrically arranged on the top of the premixing bin (205), and the output end of the electric push rod (206) is rotationally connected with the bin cover (207). The premixing stirring mechanism comprises a premixing stirring motor (208) and premixing stirring blades (209) driven by the premixing stirring motor (208), and one side of the premixing feeding hopper (203) is connected with a dust collector (204) through a pipeline. The feeding auger (301) of the main material conveying module (3) is internally provided with helical blades (303), the helical blades (303) are driven by a conveying motor (302), and the bottom of the feeding auger (301) is connected with the rack (1) through a guide support assembly (304). The stirring mechanism of the reaction and synthesis module (4) comprises a main stirring motor (404) and a stirrer (405), the main stirring motor (404) is installed on the output end of the linear module (403), the reaction kettle (401) is fixed on the rack (1) through a clamping assembly (406), and the top of the reaction kettle (401) is fixedly connected with a kettle cover (402). ​ ​ ​ ​ ​ ​ 2. The device for preparing a quick-drying polyolefin hot melt adhesive according to claim 1, characterized in that: ​ 3. The device for preparing a quick-drying polyolefin hot melt adhesive according to claim 1, characterized in that: ​ 4. The device for preparing a quick-drying polyolefin hot melt adhesive according to claim 1, characterized in that: ​ 5. The device for preparing a quick-drying polyolefin hot melt adhesive according to claim 1, characterized in that: ​ 6. The device for preparing a quick-drying polyolefin hot melt adhesive according to claim 1, characterized in that: The metering liquid adding system (502) comprises a metering pump, a flow meter and a control valve.

7. The device for preparing a quick-drying polyolefin hot melt adhesive according to claim 1, characterized in that: The temperature control system (6) comprises a heat conduction oil circulating unit flowing through the jacket of the reaction kettle (401).

8. A method for producing a quick-drying polyolefin hot melt adhesive using the production apparatus according to any one of claims 1 to 7, characterized by, The method comprises the following steps: S1, raw material preparation: providing a polyolefin base, a tackifying resin, a viscosity regulator, an antioxidant, a light curing component and a crystallization aid; wherein the light curing component comprises a photoinitiator and a polymer containing a photo-crosslinkable functional group; the crystallization aid comprises a high crystallinity polyolefin and a nucleating agent; S2, premixing and program setting: the polyolefin base, the tackifying resin, the viscosity regulator and the antioxidant are put into the premixing module (2) for preliminary mixing to obtain a premixed solid raw material; at the same time, the liquid aid is put into the liquid metering and adding system (5); the preparation program including the temperature rising curve, the stirring rate curve, the vacuum degree curve and the aid adding trigger point is set in the central control system (7); the liquid aid at least contains the light curing component; S3, initialization and feeding: starting the device, preheating the reaction kettle (401) to 100-140℃ by the central control system (7) controlling the temperature control system (6); then the premixed solid raw material is conveyed into the reaction kettle (401) through the main material conveying module (3); S4, staged melting and mixing: the central control system (7) controls the temperature control system (6) to heat the material to the final temperature of 160-220℃ according to the set temperature rising curve, and controls the stirring mechanism to operate according to the set stirring rate curve, so that the material is melted and mixed; S5, vacuum dewatering and fine dispersion: when the material is completely melted and the temperature reaches the set value, the central control system (7) starts the vacuum system to perform vacuumization in the reaction kettle (401), so that the pressure is reduced to below-0.08MPa and maintained for 10-60 minutes; at the same time, the stirring mechanism is controlled to be raised to the high-speed dispersion mode; S6, triggering the addition of the aid: when the system parameters reach the preset aid adding trigger point, the central control system (7) instructs the liquid metering and adding system (5) to add the liquid aid into the reaction kettle (401); S7, homogenization and discharging: after the addition of the aid is completed, the central control system (7) adjusts the stirring mechanism for 10-30 minutes of homogenization stirring, while maintaining the temperature and vacuum degree; finally, the vacuum is released and the product is discharged.

9. The method of claim 8, wherein: The sum of the weight parts of the light curing component and the crystallization aid accounts for 5% to 50% of the total weight of the hot melt adhesive, the polymer containing a photo-crosslinkable functional group is selected from at least one of polyolefin modified polymers having (meth)acrylate functional groups, allyl functional groups, thiol-olefin systems, or silane functional groups, the high crystallinity polyolefin is selected from at least one of linear low density polyethylene (LLDPE), high density polyethylene (HDPE), isotactic polypropylene (iPP), isotactic polybutylene (iPB), and the nucleating agent is selected from at least one of sorbitol derivatives, organic carboxylate, organic phosphate, talc, calcium carbonate.

10. The method of claim 8, wherein: In step S6, the preset auxiliary agent adding trigger point is that the viscosity of the system reaches 500-2000 cP.

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