An on-line device for interface strengthening of plastic blend materials

Abstract

This invention provides an online treatment device for strengthening the interface of plastic blends, belonging to the field of polymer material processing equipment technology. The device integrates an interface activation module in the middle section, utilizing a high-frequency alternating magnetic field to simultaneously excite the magnetostrictive micro-vibration of the inner rotor and the transient thermal field of the tooth tip skin, achieving intrinsic "thermal-mechanical" coupling at the same physical boundary and constructing a mechanochemical coupling reaction zone. The acoustic cavitation effect generated by the Helmholtz resonant cavity on the tooth side deeply strips the phase interface, and, combined with nanopores, achieves in-situ precise capture of the compatibilizer during the interface activation transient. Simultaneously, a forced cooling circuit constructs an extremely steep temperature gradient field, achieving millisecond-level thermal quenching of the reaction to lock in the metastable phase structure. Combined with online dielectric spectrum monitoring and edge computing control, deep attribution and closed-loop regulation of the reaction process are achieved. This invention effectively solves the contradiction between weak interface renewal and bulk thermal degradation in traditional processing, significantly improving the bonding strength of heterogeneous materials.

Description

Technical Field

[0001] This invention relates to the field of polymer material processing equipment technology, specifically to an online treatment device for strengthening the interface of plastic blend materials. Background Technology

[0002] In the field of polymer material processing, blending two or more plastic materials with different properties is an important means to achieve high performance and functionality of materials. Currently, the industry mainly uses twin-screw extruders as the core processing equipment. By combining the screw configurations, macroscopic shear forces are applied to the melt, and heat energy is provided by resistance heating coils outside the barrel, thereby attempting to disperse different components evenly.

[0003] To improve the interfacial bonding of incompatible systems, the current common practice is to pre-add chemical compatibilizers or grafted monomers before extrusion. During extrusion, the macroscopic thermal conduction and shear mixing of the melt promote the diffusion of the compatibilizer to the phase interface and cause a chemical reaction, thereby forming covalent bonds or physical entanglements at the interface and strengthening the interface.

[0004] Although existing blending equipment and processes are widely used, the following deep-seated technical bottlenecks still exist in the preparation of high-performance blends: Inefficient interface stripping and renewal: Traditional mechanical shearing operates within a macroscopic flow field, and its strain rate is limited by screw speed and clearance, making it difficult to achieve deep stripping of phase interfaces at the molecular chain scale. Due to the high viscosity of polymer melts, the renewal frequency of phase interfaces is low, making it difficult for compatibilizer molecules to quickly reach the new interface, thus limiting the kinetics of the interfacial reaction.

[0005] The contradiction between thermal degradation and interfacial activation: Interfacial strengthening reactions typically require high activation energies. While increasing the overall barrel temperature can accelerate the reaction, it easily leads to macroscopic thermal degradation of the heat-sensitive polymer matrix, severely impairing the material's overall mechanical properties. Current heating methods lack the ability to target energy input to the microscopic region of the "phase interface."

[0006] Insufficient energy field coupling depth: In existing devices, shear force and thermal energy are independent of each other. Shear force is mainly provided by the main screw 11, while thermal energy is conducted externally, resulting in a severe asymmetry in their spatial distribution. At the moment when energy activation is most needed at the phase interface, heat transfer delays or stress relaxation often prevent energy from being effectively used to induce interfacial grafting reactions.

[0007] Uneven utilization and distribution of compatibilizers: Premixed addition of compatibilizers results in a large amount of compatibilizer being encapsulated within the single-phase matrix rather than being enriched at the interface. This ineffective distribution not only increases costs but also becomes a weak point within the material due to the low performance of the compatibilizer itself. Summary of the Invention

[0008] Technical problems to be solved To address the shortcomings of existing technologies, this invention provides an online treatment device for strengthening the interface of plastic blends, solving the following problems: 1. Traditional methods use overall barrel heating to provide the interfacial reaction energy barrier, often leading to degradation of the polymer matrix that does not require reaction due to excessively high temperatures. This solution utilizes a high-frequency alternating magnetic field generator to induce the skin effect at the tips of the inner rotor teeth, precisely "focusing" thermal energy onto the surface of the microfluidic shear teeth. Only a very small amount of melt at the shear interface instantaneously reaches the reaction activation temperature, while the bulk melt remains at a lower temperature, achieving targeted heating. This strengthens the interface while completely avoiding overall thermal degradation of the material.

[0009] 2. Shearing based on the rotation of the main screw is a macroscopic flow. For high-viscosity melts, the delamination depth at the phase interface is limited, making it difficult for the compatibilizer to penetrate the tightly bound phase domains. This solution introduces supermagnetostrictive micro-vibration and a Helmholtz resonant cavity. Through the acoustic cavitation effect induced by high-frequency micro-vibration, an extremely high-pressure jet is generated at the microscale, forcibly "tearing apart" the two-phase interface. This multi-stage shearing, from macroscopic stretching to microscopic cavitation, achieves an exponential increase in the interfacial surface area.

[0010] 3. Premixed compatibilizers are randomly distributed in blends, with most embedded in the matrix single phase, failing to act as bridges and limiting reaction rates due to diffusion. This solution employs an online dialysis injection design using a hollow internal rotor combined with nanoscale permeable pores. During the "golden time" of interface mechanochemical activation, the compatibilizer is directly pumped to the newly formed interface through pressure and vibration, achieving in-situ precise grafting and significantly improving the utilization efficiency of the compatibilizer and the interface grafting rate.

[0011] 4. Traditional extrusion is a "black box" process, unable to know the extent of the interfacial reaction in real time, relying only on post-process sampling and testing, resulting in poor batch stability. This solution integrates a real-time dielectric spectrum monitoring loop and an edge computing adaptive control center. By capturing subtle changes in the melt's dielectric properties, it can back-calculate the interfacial grafting conversion rate in real time and automatically adjust the magnetic field spectrum and rotation speed in milliseconds. This solves the problem of uncontrollable reaction processes in complex rheological systems, ensuring constant material properties.

[0012] 5. Traditional extruders rely heavily on the main screw speed for shear strength; increasing shear inevitably increases output and pressure. This solution employs an independent drive motor and a non-contact magnetic coupling transmission assembly, achieving complete decoupling of the "conveying" and "activation" functions. Operators can independently enhance interfacial activation strength based on material properties without altering extrusion output, significantly improving the device's adaptability to extremely incompatible systems.

[0013] Technical solution To achieve the above objectives, the present invention provides the following technical solution: an online treatment device for interface strengthening of plastic blends, comprising a main extruder barrel, a main screw disposed within the main extruder barrel, and a discharge port at the top of one end of the main extruder barrel, characterized in that: An interface activation module is connected in series in the middle section of the main extruder barrel; the interface activation module includes a stator and an inner rotor coaxially disposed inside the stator, and a coupling treatment cavity is formed between the inner rotor and the stator for the blended melt to flow through; The inner rotor is made of a super magnetostrictive and high magnetic permeability composite material, and the outer surface of the inner rotor is distributed with multiple sets of microfluidic shear teeth along the axial direction. The stator is equipped with a high-frequency alternating magnetic field generator. The alternating magnetic field emitted by the high-frequency alternating magnetic field generator penetrates the stator and acts directly on the inner rotor to excite the microfluidic shear teeth to generate high-frequency magnetostrictive micro-vibrations. At the same time, based on the skin effect, a transient pulsed thermal field is synchronously induced on the surface of the microfluidic shear teeth. The local pulsed shear force induced by the high-frequency magnetostrictive micro-vibration and the transient pulsed thermal field form a completely overlapping mechanochemical coupling activation zone at the tip of the microfluidic shearing tooth. The intrinsic coupling of the "thermal-mechanical" dual field is achieved on the same physical boundary using a single external magnetic field, thereby enhancing the in-situ reaction of the polymer phase interface.

[0014] Preferably, a Helmholtz resonant cavity is formed inside the microfluidic shearing tooth, and the opening of the Helmholtz resonant cavity faces the inner wall of the stator; the high-frequency magnetostrictive micro-vibration induces the blended melt to generate acoustic cavitation microbubbles at the opening of the Helmholtz resonant cavity, and the local extreme high temperature and high pressure jet generated at the moment of collapse of the cavitation microbubbles is further superimposed on the transient pulsed thermal field, forcibly cutting off the van der Waals forces at the interface of the two-phase polymer in a non-contact manner.

[0015] Preferably, the inner rotor has a hollow structure with a compatibilizer high-pressure flow channel opened along the axial direction inside; the microfluidic shearing teeth have an array of nanoscale permeation pores connected to the compatibilizer high-pressure flow channel on their tooth surfaces; through the centrifugal force of the inner rotor and the pumping effect of the high-frequency magnetostrictive micro-vibration, the compatibilizer is directly dialyzed and injected into the microscopic voids of the polymer phase interface in an extremely activated state.

[0016] Preferably, static energy-concentrating grooves are staggered on the inner wall of the stator, and the static energy-concentrating grooves and the rotating microfluidic shearing teeth form a dynamic asymmetric tensile flow field; under the drive of the alternating magnetic field, the macroscopic interface peeling effect of the tensile flow field and the microscopic high-frequency destructive effect of the high-frequency magnetostrictive micro-vibration are superimposed, forcing the plastic blend material to undergo phase recombination under the dual force fields of macroscopic shear and microscopic high-frequency pulse.

[0017] Preferably, the high-frequency alternating magnetic field generator is driven by a nonlinear multi-frequency excitation power supply and configured to output a broadband alternating magnetic field superimposed with a fundamental frequency and higher harmonics; wherein, the fundamental frequency is used to control the heating depth and temperature peak of the skin effect on the surface of the microfluidic shear teeth, and the higher harmonics are used to precisely match and excite the mechanical resonance frequency of the supermagnetostrictive and high-permeability composite material, thereby achieving complete decoupled control of the interface pulse thermal field temperature and micro-shear intensity.

[0018] Preferably, one end of the inner rotor is connected to an external independent drive motor via a non-contact magnetic coupling transmission assembly passing through the end cover of the stator; the independent drive motor is used to drive the inner rotor to generate macroscopic rotational shearing, and its rotational speed is independent of the rotational speed of the main screw; the non-contact magnetic coupling transmission assembly is used to achieve dynamic and static isolation to prevent the high-pressure blended melt in the coupling processing cavity from leaking outward.

[0019] Preferably, the main extruder barrel is fitted with a real-time dielectric spectrum monitoring ring located directly downstream of the interface activation module; the real-time dielectric spectrum monitoring ring is configured to transmit and receive broadband sweep electromagnetic signals online, and to measure in real time the broadband dielectric loss factor and polarization relaxation time distribution of the blended melt after undergoing a compatibility reaction in the mechanochemical coupling activation region.

[0020] Preferably, it also includes an edge computing adaptive control center, which is electrically connected to the real-time dielectric spectrum monitoring loop, the nonlinear multi-frequency excitation power supply, and the independent drive motor. The edge computing adaptive control center is embedded with a topological macromolecular reaction dynamics model, which is used to adjust the spectral composition of the broadband alternating magnetic field and the speed of the independent drive motor in microsecond-level adaptive closed loop according to the characteristic peak displacement data of the broadband dielectric loss factor, thereby locking the optimal phase interface grafting conversion rate.

[0021] Preferably, the downstream end of the main extruder barrel is provided with a flash devolatilization section, which is provided with a stepped expansion flow channel and a dual-stage vacuum port on the barrel wall; the flash devolatilization section is used to force the low-molecular-weight volatile byproducts generated in the blend melt due to the in-situ grafting reaction at the interface to expand and break rapidly in a stepped depressurization environment, and be extracted through the dual-stage vacuum port to quench the reaction and solidify the interface phase structure.

[0022] Preferably, the inner rotor is further provided with a forced cooling circuit that is connected to an external refrigerant source; the forced cooling circuit and the skin heat source on the surface of the microfluidic shear teeth form an extremely steep temperature gradient field in the radial section; so that the heat of the melt activated by the transient pulse thermal field is rapidly absorbed by the forced cooling circuit the instant it passes the tooth peak of the microfluidic shear teeth, realizing millisecond-level hot quenching of the phase interface grafting reaction, which strengthens the interface bonding while completely avoiding the macroscopic thermal degradation of the polymer matrix.

[0023] Beneficial effects This invention provides an online treatment device for strengthening the interface of plastic blends. It has the following beneficial effects: 1. By leveraging the skin effect on the surface of the microfluidic shear teeth induced by a high-frequency alternating magnetic field generator, this device achieves targeted thermal energy input. Traditional technologies rely on global heating of the barrel, which often leads to bulk degradation in order to reach the interfacial reaction energy barrier. This invention confines the high temperature to the transient contact surface where shearing occurs, creating a large temperature gradient between the interfacial reaction zone and the bulk material zone. This significantly improves the interfacial grafting rate without damaging the molecular weight and physical properties of the polymer matrix.

[0024] 2. By combining the micro-vibrations generated by the supermagnetostrictive material with the acoustic cavitation effect produced by the Helmholtz resonant cavity, this device superimposes high-frequency physical impact on top of mechanical rotational shearing. Traditional screws can only achieve macroscopic mixing at the millimeter to micrometer scale; this invention can forcibly tear apart the interfaces of incompatible components at the nanoscale, significantly increasing the specific surface area of ​​the phase interface and creating a massive number of new interfaces for the penetration and reaction of compatibilizers, fundamentally solving the dispersion problem of extremely difficult-to-dissolve systems.

[0025] 3. This device utilizes a single magnetic field to simultaneously excite heating (skin effect) and mechanical vibration (magnetostriction) in the fabric, resulting in a high degree of spatial and temporal overlap between the point of strongest shear force and the point of highest temperature. In existing technologies, shearing and heating are physically separated, resulting in significant energy transfer lag. This invention achieves a "thermo-mechanical synergistic driving" mechatronic reaction, significantly reducing the interfacial activation energy, enabling the grafting process, which originally required a long reaction time, to be completed in milliseconds during extrusion.

[0026] 4. Through the nanoscale permeation pores inside the inner rotor, this device achieves dynamic in-situ injection of compatibilizer. In traditional premixing methods, a large amount of compatibilizer is in an ineffective region and unevenly distributed; this invention directly "pumps" the compatibilizer into the micropores of the newly formed interface during the transient process of interface peeling and activation, achieving precise replenishment at the molecular level. While reducing the amount of compatibilizer added (reducing costs), it significantly enhances the load transfer capacity of the phase interface.

[0027] 5. The integrated real-time dielectric spectrum monitoring loop and edge computing adaptive control center endow the device with "sensing" and "decision-making" capabilities. Traditional processing is "blind adjustment," relying on manual experience and exhibiting large fluctuations; this invention can quantify the interface grafting conversion rate in real time through dielectric signal characteristic peaks and automatically correct magnetic field and rotation speed parameters. This solves the performance instability problem caused by fluctuations in the composition of raw materials such as recycled mixed plastics, ensuring a high degree of consistency in the quality of the finished product.

[0028] 6. Because the inner rotor is driven by an independent servo motor and the thermal field is controlled by magnetic field induction, the shear strength, interface temperature, and extrusion output of the device are completely decoupled. Traditional equipment balances output and mixing by adjusting the main screw speed, resulting in poor adjustment flexibility; this invention can customize parameters for blending systems with different viscosity ratios and reaction kinetics, exhibiting strong versatility and adaptability to research and production. Attached Figure Description

[0029] Figure 1 This is an isometric view of the device of the present invention; Figure 2 This is an overall schematic diagram of the device of the present invention; Figure 3 This is a front view of the device of the present invention; Figure 4 This is a side view of the device of the present invention; Figure 5 This is a schematic diagram of the dual-stage vacuum port of the present invention; Figure 6 This is a physical spatial distribution diagram of the device of the present invention; Figure 7 This is a functional block diagram of the present invention; Figure 8 This is a cloud diagram illustrating the device system composition of the present invention; Figure 9 This is a flowchart of the process of the present invention.

[0030] The components include: 1. Main extruder barrel; 2. Discharge port; 3. Interface activation module; 4. Non-contact magnetic coupling transmission assembly; 5. Independent drive motor; 6. Real-time dielectric spectrum monitoring ring; 7. Flash evaporation and devolatilization section; 8. Dual-stage vacuum port. Detailed Implementation

[0031] 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. Specific Implementation Example 1: like Figures 1 to 9As shown, an online treatment device for interface strengthening of plastic blends includes a main extruder barrel 1, a main screw disposed within the main extruder barrel 1, and a discharge port 2 at the top of one end of the main extruder barrel 1, characterized in that: An interface activation module 3 is connected in series in the middle section of the main extruder barrel 1; the interface activation module 3 includes a stator and an inner rotor coaxially disposed inside the stator, and a coupling treatment cavity is formed between the inner rotor and the stator for the blended melt to flow through. The inner rotor is made of a super magnetostrictive and high magnetic permeability composite material, and the outer surface of the inner rotor is distributed with multiple sets of microfluidic shear teeth along the axial direction. The stator is equipped with a high-frequency alternating magnetic field generator. The alternating magnetic field emitted by the high-frequency alternating magnetic field generator penetrates the stator and acts directly on the inner rotor to excite the microfluidic shear teeth to generate high-frequency magnetostrictive micro-vibrations. At the same time, based on the skin effect, a transient pulsed thermal field is synchronously induced on the surface of the microfluidic shear teeth. The local pulsed shear force induced by the high-frequency magnetostrictive micro-vibration and the transient pulsed thermal field form a completely overlapping mechanochemical coupling activation zone at the tip of the microfluidic shearing tooth. The intrinsic coupling of the "thermal-mechanical" dual field is achieved on the same physical boundary using a single external magnetic field, thereby enhancing the in-situ reaction of the polymer phase interface.

[0033] The core of this device 100 lies in the special material and structural design of the inner rotor. The surface microfluidic shear teeth of the inner rotor are not made of traditional steel, but are a composite layer composed of Tb-Dy-Fe super magnetostrictive alloy particles and a high-permeability nickel-iron substrate.

[0034] When a high-frequency current is applied to the high-frequency alternating magnetic field generator inside the stator, the magnetic lines of force penetrate the stator and enter the coupling processing cavity. Based on the supermagnetostrictive effect, the microfluidic shearing teeth will generate axial or radial high-frequency micro-deformation during the alternating magnetic field process, with a vibration frequency of 20kHz to 50kHz. This microsecond-level mechanical vibration, combined with the macroscopic rotational shearing of the inner rotor driven by the independent drive motor 5, forms a dual stress system of "macroscopic flow field stretching" and "microscopic high-frequency pulse impact" inside the blend melt, which can effectively destroy the strong van der Waals forces between polymer long chains and achieve deep exfoliation at the interface level.

[0035] A Helmholtz resonant cavity of a specific volume is designed on the sidewall of the microfluidic shearing tooth. When the melt flows through the high-speed rotating shearing tooth accompanied by high-frequency vibration, the melt micro-elements within the resonant cavity generate periodic pressure fluctuations. When the frequency of the pressure fluctuations matches the natural frequency of the cavity, it induces a violent acoustic cavitation phenomenon. At the moment of collapse of the cavitation microbubbles, an extremely powerful local jet and instantaneous high pressure of hundreds of megapascals are generated. This energy release can directly act on the phase interface of two incompatible polymers, forcing the molecular chains to undergo violent entanglement in a very short time, providing the physical prerequisite for subsequent grafting reactions.

[0036] This invention ingeniously utilizes the skin effect of electromagnetic induction to achieve precise energy delivery. By adjusting the frequency of the nonlinear multi-frequency excitation power supply, an induced current is generated within an extremely thin layer on the surface of the microfluidic shear teeth.

[0037] This design allows heat to be generated instantaneously only at the tooth tip, where shearing is most intense and stress is concentrated, forming a transient pulsed thermal field. This thermal field completely overlaps spatially with the aforementioned microscopic stress field. This "in-situ coupling" significantly reduces the apparent activation energy of the compatibilization reaction, enabling the chemical bonding between the compatibilizer and the polymer matrix to be completed efficiently at a relatively low bulk temperature. This solves the persistent technical problems of material yellowing and thermal degradation that are easily encountered in traditional bulk heating modes.

[0038] The compatibilizer is delivered through a high-pressure flow channel inside the inner rotor and discharged through nanoscale permeation pores on the microfluidic shear teeth. Because the pore size is on the nanoscale, high-viscosity polymer chains cannot enter the pores due to surface tension, while low-molecular-weight compatibilizers are evenly distributed on the surface of the shear teeth like "sweating" under the "pumping" action of magnetostrictive vibration.

[0039] This "dynamic dialysis" mechanism ensures that the compatibilizer molecules are immediately placed in the highest-energy chemical coupling activation region the moment they escape from the pore, and quickly capture the newly detached interface, thus maximizing the grafting efficiency.

[0040] To stabilize the microstructure generated by the interfacial reaction, a forced cooling circuit is installed inside the inner rotor. Under the action of this circuit, the rotor substrate is maintained at a low temperature. When the material leaves the tip thermal field of the microfluidic shear teeth, it quickly comes into contact with the relatively low-temperature rotor surface. This extremely steep temperature gradient, reaching over 100 degrees Celsius per millimeter, acts as a "rapid quenching" effect, terminating the chemical reaction and freezing the phase structure within milliseconds, effectively preventing secondary separation or phase domain coarsening at the interface.

[0041] The real-time dielectric spectrum monitoring ring 6 uses broadband electromagnetic wave scanning to acquire real-time changes in the dielectric constant and loss factor of the melt during the interface polarization process. The edge computing adaptive control center calculates the interface grafting conversion rate in real time based on the monitored displacement of the dielectric loss characteristic peak.

[0042] When the conversion rate falls below a preset threshold, the central control unit automatically instructs the excitation power supply to increase the harmonic amplitude, thereby enhancing the magnetostrictive vibration amplitude and skin heating intensity. This online closed-loop regulation based on the molecular-level response of materials enables the device to adapt to the modification needs of raw materials with drastic fluctuations in composition, such as waste plastics, ensuring the consistency of the mechanical properties of the produced materials. Specific Implementation Example 2: like Figures 1 to 9 As shown, based on the content of the above specific embodiments, the following content is further disclosed: The core of this device 100 lies in transforming the traditional continuous extrusion process into a three-stage dynamic reaction process of "conveying-activation-locking". The main extruder barrel 1 completes the initial melting and conveying of materials through the main screw.

[0044] The interface activation module 3 is embedded as an independent unit. To achieve complete freedom in process parameters, the inner rotor is driven by an external independent drive motor 5 via a non-contact magnetic coupling transmission assembly 4. This design completely solves the drawback of traditional equipment where shear strength is highly dependent on screw speed, enabling the application of extremely high-frequency interface peeling forces even under low-volume and low-speed conveying conditions.

[0045] The stator not only serves as a pressure vessel but also as a source of energy fields. Its internally embedded high-frequency alternating magnetic field generator is driven by a nonlinear multi-frequency excitation power supply.

[0046] Spectrum division design: The power supply outputs a mixed frequency signal, in which the low-frequency fundamental frequency component is used to control the skin depth of induction heating, ensuring that heat is generated only within a depth of 0.1 to 0.5 mm on the surface of the microfluidic shear teeth; the high-frequency harmonic component is used to precisely match the magnetostrictive resonant frequency of the inner rotor material.

[0047] Stator structural details: The inner wall of the stator is equipped with a magnetically permeable and heat-insulating layer made of high-performance ceramic material, which can ensure the undamaged penetration of magnetic lines of force and prevent the high temperature in the coupling processing cavity from being reversed to the coil.

[0048] The internal rotor is the core actuator for achieving interface enhancement, and its technical details include the following three dimensions: Composite material system: The teeth of the inner rotor are made of a gradient composite material of Tb-Dy-Fe super magnetostrictive alloy and high-permeability nickel-based alloy. Under an alternating magnetic field, the teeth will generate micro-high-frequency vibrations with a frequency of 20kHz to 50kHz and an amplitude of 10μm to 50μm.

[0049] Geometric mechanics of microfluidic shearing teeth: The shearing teeth adopt an asymmetric eccentric design, with three levels of fractal flow channels machined at the tooth peaks. The first level is a macroscopic stretching flow channel, used to reduce the particle size of the dispersed phase; the second level is a Helmholtz resonant cavity, which utilizes the compressibility of the melt under high-frequency vibration to generate an acoustic cavitation effect; the third level is a sharp peeling edge at the tooth tip, used to apply forced shearing at the molecular chain scale.

[0050] Targeted thermal field induction: Utilizing the skin effect, an alternating magnetic field induces a transient high current density at the sharp edges of the shear teeth, generating a localized pulsed thermal field. This thermal field spatially coincides with the mechanical vibration, forming a "thermo-mechanical synergistic" reaction zone. To address the issue of uneven distribution of the compatibilizer in the matrix, this device incorporates an internal replenishment mechanism within the inner rotor: High-pressure flow channel and nano-permeable pores: A high-pressure flow channel for compatibilizer is opened in the center of the inner rotor, and liquid or supercritical compatibilizer is introduced through a rotary joint.

[0051] Interface trapping mechanism: Permeable pores with a diameter of 100 to 300 nanometers are arrayed on the side of the microfluidic shearing teeth. Because the pore size is much smaller than the rotation radius of the polymer melt macromolecular chains, the high-frequency vibration of the rotor generates a repulsive effect, allowing only compatibilizers with smaller molecular weights to enter the coupling processing chamber through the permeable pores. Upon entering the chamber, the compatibilizer immediately encounters the newly formed interface that has been strongly sheared away, and an in-situ grafting reaction immediately occurs.

[0052] To prevent secondary aggregation or thermal degradation of materials after the interface reaction, the inner rotor is designed with a forced cooling circuit: Instantaneous quenching principle: The inner rotor substrate is kept at a low temperature by a forced cooling circuit. After the molten micro-element flows through the peak thermal field zone of the shear teeth and completes the reaction, it enters the valley zone with rotation and rapidly transfers heat to the low-temperature rotor substrate.

[0053] Effect: This design creates an extremely steep temperature gradient in the radial section, with a temperature difference of up to 100 degrees Celsius / mm. Through the "hot quenching" effect, the phase interface structure is forcibly locked, preventing the phase domains from coarsening during subsequent transport.

[0054] The device is equipped with a real-time dielectric spectrum monitoring ring 6 at the end, which obtains the complex permittivity of the melt at different frequencies through high-frequency scanning.

[0055] Information extraction: The system extracts the interface polarization characteristic peaks, the displacement and intensity of which directly correspond to the density of interface grafting.

[0056] Adaptive feedback: The edge computing adaptive control center receives the signal, uses deep learning algorithms to predict the interface bonding force strength in real time, and automatically fine-tunes the magnetic field frequency, magnetic field strength and inner rotor speed, realizing a technological leap from "experience-based processing" to "performance-driven processing".

[0057] Following the interface enhancement section, there is a flash evaporation and devolatification section 7.

[0058] Expansion channel design: The cross-section of the channel is expanded in a stepwise manner, and the trace amounts of additives or reaction byproducts dissolved in the melt are flashed by the sudden pressure drop.

[0059] Dual-stage vacuum 8: The first stage is used to remove entrained gas during the arrangement of macromolecular chain segments, and the second stage of high vacuum is used to remove reaction residues, ultimately obtaining a blended modified material with strong interfacial bonding and very few internal defects. Specific Implementation Example 3: like Figures 1 to 9 As shown, based on the content of the above specific embodiments, the working principle of the present invention is further disclosed: An in-situ mechanochemical synergistic reaction mechanism induced by an external physical field. It changes the traditional blending logic that relies on passive mixing via a master screw, instead actively creating an interface activation environment at the microscale through electromagnetic coupling. The detailed working principle is as follows: Macro-micro multi-level stripping principle: When the plastic blend melt enters the interface activation module 3, it first undergoes a two-stage peeling process: Macroscopic layer: The independent drive motor 5 drives the inner rotor to rotate at high speed, and the narrow gap between it and the stator forms a strong tensile flow field, which stretches the large-sized dispersed phase into a layered or linear shape.

[0061] Microscopic layer: The alternating magnetic field excited by the high-frequency alternating magnetic field generator causes the microfluidic shear teeth to generate high-frequency magnetostrictive micro-vibrations of 20-50kHz. This high-frequency pulse acts directly on the interface where the macromolecular chains are most tightly entangled, producing an effect similar to "ultrasonic fragmentation," further pulverizing and peeling off the macroscopic layered structure, exposing a large number of phase interfaces.

[0062] The intrinsic coupling activation principle of "magnetism-thermal-mechanical": This is the most crucial chemical activation process in this invention, which solves the reaction energy barrier problem: Physical field focusing: Due to the skin effect of the alternating magnetic field, the induced current is concentrated on the surface of the shearing teeth. This means that at the tooth tip where the shear force is strongest and the stress concentration is highest, the temperature also rises to its highest instantaneous value.

[0063] Mechanochemical synergy: High-frequency shearing in physics tears apart polymer chains, generating a large number of highly active free radicals; at the same time, the targeted heat provided by the skin effect instantly satisfies the activation energy required for the grafting reaction.

[0064] Result: The absolute overlap of the thermal field and the force field in space and time allows the compatibility reaction to be completed instantaneously in the milliseconds when the melt contacts the tooth tip, without the need for a long bulk heat conduction.

[0065] In-situ supply and capture principle: This solution solves the problem of uneven distribution of compatibilizer: Directional migration: Under the combined action of pressure in the high-pressure channel and micro-vibration of the rotor, the compatibilizer is extruded outward through nanoscale permeation pores.

[0066] Precise capture: At this moment, the permeation pore outlet is precisely located in the aforementioned "mechanical-chemical synergistic activation zone." The newly formed interface of the highly active polymer chain segments, which have just been stripped, immediately "captures" the escaped compatibilizer molecules. This replenishment method avoids dilution of the compatibilizer by the matrix phase, ensuring that each molecule of compatibilizer acts precisely on the phase interface.

[0067] Helmholtz resonance and microjets enhancement principle: To further enhance the mixing of extremely incompatible systems: Microscopic blasting: When the melt flows through the Helmholtz resonant cavity on the side of the shear teeth, the high-frequency vibration induces violent pressure fluctuations in the cavity, generating acoustic cavitation microbubbles.

[0068] Phase interface penetration: The microjets generated by the collapse of cavitation bubbles have extremely high instantaneous kinetic energy, which can pierce the interface layer between two phases like "nano needles", forcibly driving polar molecules and non-polar molecules to become entangled.

[0069] Steep gradient hot quenching locking principle: Structural solidification after the reaction is complete is crucial: Instant termination: After the melt leaves the tooth tip activation zone, due to the presence of the forced cooling circuit inside the inner rotor, the material quickly comes into contact with the relatively low temperature rotor substrate.

[0070] Structural locking: The extremely high cooling rate achieves "hot quenching", which rapidly cools the metastable interface phase formed by the grafting reaction to below the glass transition temperature or below the crystal point, effectively preventing the phase domains from re-aggregating and coarsening in the subsequent homogenization stage.

[0071] Rheology-dielectric closed-loop control principle: Finally, the device achieves adaptive processing through dynamic monitoring: Online diagnostics: Real-time dielectric spectrum monitoring ring 6 monitors the melt polarization response. When the interface bonding is weak, the characteristic peak of the dielectric loss factor shifts.

[0072] Intelligent prescription: After receiving signals, the edge computing center adjusts the magnetic field frequency and rotor speed to instantly increase the shear frequency or local temperature. This ensures that even if the raw material composition fluctuates, the interface strengthening effect of the produced material remains constant.

[0073] The working principle of this device is not a simple physical mixing, but rather utilizes the electromagnetic induction effect to artificially construct a high-energy, high-frequency, transient mechanochemical reaction field within a specific micro-region of the extrusion channel. This energy field precisely activates and cools the interface, thereby achieving high-strength interfacial bonding of heterogeneous materials without compromising the properties of the matrix. Specific Implementation Example 4: like Figures 1 to 9 As shown, based on the content of the above specific embodiments, the following content is further disclosed, and specific use cases are provided below: Case Background: Processed materials: 80% recycled polypropylene (PP), non-polar + 20% polyamide 6 (PA6), highly polar.

[0075] Additive: Maleic anhydride-grafted polypropylene as a compatibilizer.

[0076] Traditional pain points: PP and PA6 are extremely incompatible. After traditional mixing, PA6 is suspended in coarse particles. When the material is subjected to impact, the interface is prone to cracking. In addition, PA6 requires high processing temperature, which often leads to PP degradation.

[0077] Startup and parameter settings: The operator sets the temperature of the main extruder barrel 1 to 210°C via the control panel to maintain PP melting, while simultaneously setting the speed of the independent drive motor 5 of the interface activation module 3 to 800 rpm. This decoupling from the main screw speed ensures that even at low production volumes, extremely high shear frequencies can be achieved at the interface.

[0078] Mechatronic activation process: When the PP / PA6 melt flows through the coupling processing cavity, the high-frequency alternating magnetic field generator is turned on.

[0079] Microscopic tearing: The microfluidic shearing teeth of the inner rotor generate micro-vibrations at 30 kHz under the drive of a magnetic field. Large PA6 droplets in the melt are rapidly torn into nano-sized droplets by the high-frequency impact of the tooth tips, and the phase interface area expands thousands of times instantaneously.

[0080] Targeted heating: At this point, the magnetic field induces a skin effect at the tooth tip. At the boundary where PA6 microdroplets contact PP, the local instantaneous temperature rises to 240°C, the active temperature of PA6, while the bulk melt remains at 210°C. This is like performing "surgery" on the surface of ice with a laser, both activating the reaction and protecting the PP matrix from degradation.

[0081] Precision grafting: In the millisecond instant of interface stripping and activation, PP-g-MAH in the high-pressure channel of the compatibilizer seeps out through the nanoscale permeation pores on the tooth side under pressure.

[0082] In-situ capture: Compatibilizer molecules appear directly at the newly formed interface between PA6 nanodroplets and PP. Driven by the acoustic cavitation jet generated by the Helmholtz resonant cavity, the polar groups of the compatibilizer rapidly combine with the PA6 molecular chain, while the other end entangles with PP, forming an extremely strong "interfacial bridge".

[0083] Real-time diagnosis and feedback adjustment: Material flows through dielectric spectrum real-time monitoring ring 6.

[0084] Intelligent recognition: The edge computing adaptive control center recognizes the characteristic peak of the dielectric loss factor shifting to a higher frequency and determines that the interface grafting rate has reached 95%.

[0085] Adaptive control: When fluctuations in the composition of recycled PP in the raw materials lead to a weakening of interfacial polarization, the central control will automatically increase the excitation current frequency and enhance the magnetostriction amplitude, thereby compensating for the insufficiency of the chemical reaction by enhancing physical stripping.

[0086] Hot quenching locking and output: The melt after the reaction flows closely along the surface of the rotor, which has a forced cooling circuit, and the chemical bonding state at the interface is rapidly "frozen". It then enters the flash devolatilization section 7, where trace amounts of small molecules generated in the reaction are removed through the dual-stage vacuum port 8.

[0087] Final result comparison: .

[0088] In this case, the device not only performs simple "mixing" but also functions as a continuously operating micro-chemical reactor. Through magnetic field-induced intrinsic thermo-mechanical coupling, it overcomes the "phase interface reaction energy barrier" problem that traditional processes cannot overcome, enabling low-cost recycled plastics to exhibit the mechanical properties of high-performance engineering plastics.

[0089] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising a reference structure" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0090] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An on-line plastic blend interfacial strengthening treatment apparatus, characterized by: The main extruder barrel (1) includes a main screw disposed within the main extruder barrel (1) and a discharge port (2) at the top of one end of the main extruder barrel (1), characterized in that: An interface activation module (3) is connected in series in the middle section of the main extruder barrel (1); the interface activation module (3) includes a stator and an inner rotor coaxially disposed inside the stator, and a coupling treatment cavity for the blended melt to flow through is formed between the inner rotor and the stator; The inner rotor is made of a super magnetostrictive and high magnetic permeability composite material, and the outer surface of the inner rotor is distributed with multiple sets of microfluidic shear teeth along the axial direction. The stator is equipped with a high-frequency alternating magnetic field generator. The alternating magnetic field emitted by the high-frequency alternating magnetic field generator penetrates the stator and acts directly on the inner rotor to excite the microfluidic shear teeth to generate high-frequency magnetostrictive micro-vibrations. At the same time, based on the skin effect, a transient pulsed thermal field is synchronously induced on the surface of the microfluidic shear teeth. The local pulsed shear force induced by the high-frequency magnetostrictive micro-vibration and the transient pulsed thermal field form a completely overlapping mechanochemical coupling activation zone at the tip of the microfluidic shearing tooth. The intrinsic coupling of the "thermal-mechanical" dual field is achieved on the same physical boundary using a single external magnetic field, thereby enhancing the in-situ reaction of the polymer phase interface.

2. The apparatus for on-line interface strengthening of plastic blend material according to claim 1, wherein: The microfluidic shearing teeth have a Helmholtz resonant cavity inside, and the opening of the Helmholtz resonant cavity faces the inner wall of the stator. The high-frequency magnetostrictive micro-vibration causes the blended melt to generate acoustic cavitation microbubbles at the opening of the Helmholtz resonant cavity. The local extreme high temperature and high pressure jet generated at the moment of collapse of the cavitation microbubbles is further superimposed on the transient pulsed thermal field, forcibly cutting off the van der Waals forces at the interface of the two-phase polymer in a non-contact manner.

3. The apparatus of claim 1, wherein: The inner rotor has a hollow structure with a compatibilizer high-pressure flow channel opened along the axial direction inside; the microfluidic shearing teeth have an array of nanoscale permeation pores connected to the compatibilizer high-pressure flow channel on their tooth surfaces; through the centrifugal force of the inner rotor and the pumping effect of the high-frequency magnetostrictive micro-vibration, the compatibilizer is directly dialyzed and injected into the microscopic voids of the polymer phase interface in an extremely activated state.

4. The apparatus of claim 1, wherein: The inner wall of the stator is staggered with static energy-concentrating grooves, which together with the rotating microfluidic shearing teeth form a dynamic asymmetric tensile flow field. Driven by the alternating magnetic field, the macroscopic interface peeling effect of the tensile flow field and the microscopic high-frequency destructive effect of the high-frequency magnetostrictive micro-vibration are superimposed, forcing the plastic blend material to undergo phase recombination under the dual force fields of macroscopic shear and microscopic high-frequency pulse.

5. The apparatus of claim 1, wherein: The high-frequency alternating magnetic field generator is driven by a nonlinear multi-frequency excitation power supply and is configured to output a broadband alternating magnetic field superimposed with a fundamental frequency and higher harmonics. The fundamental frequency is used to control the heating depth and temperature peak of the skin effect on the surface of the microfluidic shear teeth, and the higher harmonics are used to precisely match and excite the mechanical resonance frequency of the supermagnetostrictive and high-permeability composite material, thereby achieving complete decoupled control of the interface pulse thermal field temperature and micro-shear intensity.

6. The apparatus of claim 1, wherein: One end of the inner rotor is connected to an external independent drive motor (5) through the end cover of the stator via a non-contact magnetic coupling transmission assembly (4); the independent drive motor (5) is used to drive the inner rotor to generate macroscopic rotational shearing, and its speed is independent of the speed of the main screw; the non-contact magnetic coupling transmission assembly (4) is used to achieve dynamic and static isolation to prevent the high-pressure blended melt in the coupling processing cavity from leaking outward.

7. The online treatment device for interface strengthening of plastic blend materials according to claim 1, characterized in that: The main extruder barrel (1) is fitted with a dielectric spectrum real-time monitoring ring (6) located directly downstream of the interface activation module (3); the dielectric spectrum real-time monitoring ring (6) is configured to transmit and receive broadband sweep electromagnetic signals online, and to measure in real time the broadband dielectric loss factor and polarization relaxation time distribution of the blended melt after undergoing compatibility reaction in the mechanochemical coupling activation zone.

8. The online treatment device for interface strengthening of plastic blend materials according to claim 7, characterized in that: It also includes an edge computing adaptive control center, which is electrically connected to the dielectric spectrum real-time monitoring ring (6), the nonlinear multi-frequency excitation power supply and the independent drive motor (5) respectively; the edge computing adaptive control center is embedded with a topological macromolecular reaction dynamics model, which is used to adjust the spectrum composition of the broadband alternating magnetic field and the speed of the independent drive motor (5) in microsecond-level adaptive closed loop according to the characteristic peak displacement data of the broadband dielectric loss factor, and lock the optimal phase interface grafting conversion rate.

9. The online treatment device for interface strengthening of plastic blend materials according to claim 1, characterized in that: The downstream end of the main extruder barrel (1) is provided with a flash devolatilization section (7), which is provided with a stepped expansion flow channel and a dual-stage vacuum port (8) on the barrel wall. The flash devolatilization section (7) is used to force the low molecular weight volatile byproducts generated by the in-situ grafting reaction of the interface inside the blend melt to expand and break rapidly in a stepped depressurization environment, and be extracted through the dual-stage vacuum port (8) to quench the reaction and solidify the interface phase structure.

10. The online treatment device for interface strengthening of plastic blend materials according to claim 1, characterized in that: The inner rotor is also equipped with a forced cooling circuit that is connected to an external refrigerant source. The forced cooling circuit and the skin heat source on the surface of the microfluidic shear teeth form an extremely steep temperature gradient field in the radial section. This allows the heat of the melt activated by the transient pulsed thermal field to be rapidly absorbed by the forced cooling circuit the instant it passes the peak of the microfluidic shear teeth, achieving millisecond-level thermal quenching of the phase interface grafting reaction. This strengthens the interfacial bonding while completely avoiding the macroscopic thermal degradation of the polymer matrix.

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