Curing stress testing method and device suitable for light curing, heat curing and coupling curing of light curing and heat curing

Abstract

The invention provides a curing stress test method and device suitable for light, heat and coupling curing thereof, and the device comprises a curing stress obtaining module which is used for obtaining the curing stress of a sample in a curing reaction in real time; the reaction temperature acquisition module is used for acquiring the reaction temperature of the sample in the curing reaction in real time; the sample thickness adjusting module is used for adjusting the thickness of the sample; the rigidity adjusting module is used for adjusting the constraint rigidity of the sample during reaction; the environment temperature control module is used for controlling the reaction temperature in the thermocuring reaction; the curing light source control module is used for controlling the illumination condition in the light curing reaction; and the acquisition module is connected with the curing stress acquisition module and the reaction temperature acquisition module and is used for adjusting the acquisition time and frequency of the curing stress and / or the reaction temperature so as to realize simultaneous and synchronous acquisition of the curing stress and the reaction temperature.

Description

Technical Field

[0001] The present application relates to the field of sample performance testing, and in particular to a curing stress testing method and device suitable for light, heat and their coupled curing. Background Art

[0002] As the two mainstream methods for polymer curing, photocuring and thermal curing technologies play a vital role in many fields such as sample science, engineering and nanotechnology.

[0003] Stereolithography (SLA) technology is renowned for its rapid curing speed, precise controllability, and environmental friendliness, particularly in 3D printing, coatings, and adhesives. In contrast, thermosetting polymers are favored for their superior mechanical properties, thermal stability, and corrosion resistance, and are widely used in coatings, electronic packaging, and fiber-reinforced composites.

[0004] In both curing techniques, when external energy (such as light of a specific wavelength or high temperature) acts on liquid monomers or oligomers, a chain curing reaction is initiated, resulting in the formation of a solid, cross-linked polymer product. At the molecular level, this process involves a shift in the interactions between adjacent monomers, from physical bonds (such as van der Waals forces, hydrogen bonds, and electrostatic forces) to chemical covalent bonds. This is accompanied by a reduction in the molecular distance and a tighter molecular arrangement. Macroscopically, this manifests as volumetric solidification of the cured sample. In practical applications, this volumetric contraction is constrained by the surrounding rigid matrix, generating curing stresses within the sample and at the sample / interface. The presence of these curing stresses has a profound impact on the quality and lifespan of the cured sample, for example, causing structural deformation and warping, resulting in dimensional inaccuracies. It can also lead to a decrease in the sample's mechanical properties, weakening interlayer bonding, increasing brittleness, and shortening the sample's lifespan.

[0005] Several photocuring and thermal curing testing devices and methods have been reported both domestically and internationally. For photocuring, methods include electronic speckle pattern testing, stress-strain analysis, and stress testing. However, direct measurement methods cannot avoid the influence of test temperature and therefore have low accuracy. Displacement / force sensing methods, such as adhesive disks and strain gauges, can only measure curing after the gel point (the starting point for polymer cross-linking network formation and sample stiffness establishment), but cannot measure volume changes before the gel point, thus failing to accurately characterize the complete curing process. Optical methods, such as digital image correlation, are susceptible to sample flow and external vibration, placing extremely high demands on the testing environment and noise levels. Fiber Bragg grating methods require sensors to be embedded within the sample, which can alter the sample's structure and properties, thereby affecting intrinsic curing. For thermal curing, methods include differential scanning calorimetry (DSC), modulated scanning calorimetry (MDSC), thermomechanical analysis (TMA), strain gauge embedding, and multi-parameter online monitoring systems. DSC and MDSC techniques test small samples, differ significantly from actual production, and cannot be monitored online in real time. The TMA method can measure dimensional changes in real time, but the stress relief process may alter the specimen's degree of cure and moisture content, resulting in test errors. The strain gauge embedding method is suitable for symmetrical layups and cannot directly monitor stress. These methods still face challenges in accuracy, cost, and equipment complexity in practical applications. For samples cured by photo-thermal coupling, existing testing methods primarily combine photo- and thermal-curing monitoring techniques, such as multi-sensor fusion (fiber Bragg gratings and digital image correlation), simultaneous temperature-strain field tracking using infrared thermal imaging, and numerical simulation of staged photo-thermal control. However, these methods have significant limitations, including data conflicts caused by differences in photo- and thermal-curing methods, interference from multi-physics coupling, dynamic response and resolution limitations, high equipment integration complexity, and incompatibility between test methods for different curing methods.

[0006] The above analysis reveals the following problems and drawbacks of the existing technologies: Existing photocuring testing technologies primarily suffer from low measurement accuracy, an inability to characterize the complete curing process, high measurement costs, and the potential for impact on the intrinsic curing of samples; existing thermal curing technologies primarily suffer from inability to detect in real time, large measurement errors, and equipment complexity; and existing photo-thermal coupling curing technologies, which are merely a simple combination of photo-curing and thermal curing testing methods, can present issues such as data conflicts due to differences in photo- and thermal curing methods, multi-physics coupling interference, dynamic response and resolution limitations, and high equipment integration complexity. Furthermore, existing testing methods and devices are difficult to apply simultaneously to photocuring, thermal curing, and photo-thermal coupling curing testing conditions. Therefore, a concise and efficient testing method and device that can be applied to photocuring, thermal curing, and photo-thermal coupling curing testing conditions is needed. Summary of the Invention

[0007] In view of this, the present application provides a curing stress testing device and method suitable for light, heat and their coupled curing, aiming to solve the stress testing problems of simultaneous light curing, heat curing and light-heat coupled curing.

[0008] In a first aspect, the present application provides a curing stress testing device suitable for light, heat and their coupled curing, comprising: A curing stress acquisition module is used to obtain the curing stress of the sample during the curing reaction in real time; A reaction temperature acquisition module is used to obtain the reaction temperature of the sample during the curing reaction in real time; Sample thickness adjustment module, used to adjust the thickness of the sample; A stiffness adjustment module is used to adjust the constraint stiffness of the sample during the reaction; An environmental temperature control module, used to control the reaction temperature during the thermal curing reaction; Curing light source control module, used to control the lighting conditions in the light curing reaction; The acquisition module is connected to the curing stress acquisition module and the reaction temperature acquisition module, and is used to adjust the acquisition time and frequency of the curing stress and / or reaction temperature to achieve simultaneous synchronous acquisition of the curing stress and reaction temperature.

[0009] Optionally, the curing stress acquisition module includes: cantilever beam; The first data acquisition unit includes a capacitive displacement sensor at the end of the cantilever beam, which is used to collect the deflection of the end of the cantilever beam caused by the force generated by the curing of the sample during the curing reaction and the corresponding time; a first data processing unit, configured to plot the data collected by the first data collection unit into a displacement-time curve; The curing stress calculation unit is used to calculate the curing stress of the sample at each time point during the reaction process based on the displacement-time curve and the sample mechanical beam theory, after correcting the shear stress, and fully depict the dynamic evolution process of the curing stress.

[0010] Optionally, the reaction temperature acquisition module includes: Thermocouple temperature sensor system; The second data acquisition unit is used to collect the potential of the thermocouple wire during the curing reaction; a second data processing unit, for converting the electric potential into a real-time temperature during the curing reaction; The reaction temperature calculation unit is used to convert the temperature into the real-time temperature of the sample through a calculator.

[0011] Optionally, the sample thickness adjustment module includes: Three-axis displacement platform system, used to clamp samples and drive them to move; The first control unit is used to control the movement of the three-axis displacement platform in the X, Y, and Z directions; The third data acquisition unit, the capacitive displacement sensor inside the platform, is used to collect the displacement in the Z direction during the movement of the platform.

[0012] Optionally, the stiffness adjustment module includes: cantilever beam; A second control unit is used to adjust cantilever beams of different sizes and materials; The third control unit is used to adjust the position of the clamp on the cantilever beam.

[0013] Optionally, the ambient temperature control module includes: Temperature box, used to provide temperature environment for samples; A fourth control unit, used to control the set temperature of the environment in which the sample is located; The fourth data acquisition unit includes a thermocouple temperature sensor disposed inside the temperature box, and is used to acquire the actual temperature inside the temperature box.

[0014] Optionally, the curing light source control module includes: UV-LED curing light source, used to provide a light source environment for the sample; The fifth control unit is used to control the irradiation intensity and irradiation time of the curing light.

[0015] Optionally, the curing stress testing device suitable for light, heat and their coupled curing further includes: The optimization module is used to adjust the reaction conditions and / or sample components in the curing reaction according to the obtained curing stress, so as to optimize the curing stress of the sample.

[0016] In a second aspect, the present application provides a curing stress testing method applicable to light, heat, and coupled curing, characterized in that it is applied to the device as described in any one of the above items, comprising: Filling the sample into the sample thickness adjustment module, and adjusting the sample thickness according to the sample thickness adjustment module, and adjusting the constraint stiffness of the sample through the stiffness adjustment module; According to the curing conditions, the temperature conditions and light source conditions are set through the ambient temperature control module and / or the curing light source control module; The curing stress and reaction temperature of the sample are obtained through the acquisition module, the curing stress acquisition module and the reaction temperature acquisition module.

[0017] Alternatively, by determining the change in deflection of the cantilever beam system caused by the sample, the curing stress σ of the material during the curing reaction is obtained from the deflection δ; the formula is as follows:

[0018] Where, and are the elastic modulus of the cantilever beam system and the moment of inertia of the beam section, respectively; is the length of the cantilever beam system; is the distance from the sample to the fixed end; is the Poisson's ratio of the beam material; is the sample surface area; Indicates deflection.

[0019] The technical solution provided by this application has the following beneficial effects: First, the present invention aims at measuring the curing stress under different curing conditions, that is, under the conditions of light curing, heat curing and light-heat coupling curing, to realize the simultaneous synchronous testing of the curing stress and reaction temperature of the material in the curing reaction, in order to test the dynamic data under the conditions of light curing, heat curing and light-heat coupling curing, and intuitively reveal the real-time evolution of the mechanical properties of the material under different curing conditions; at the same time, through the thickness adjustment module and the stiffness adjustment module, the working conditions of the test material are precisely controlled, and the curing stress evolution mechanism under different working conditions is quantitatively studied.

[0020] The present invention combines a high-precision cantilever beam structure, a temperature control box, a curing light source, and a thermocouple to construct a testing device for curing stress under light curing, heat curing, and light-heat coupled curing conditions. This device enables real-time coupled testing of the curing stress and reaction temperature of polymers and their composite materials (with a test frequency of up to 10 Hz). This testing device can provide experimental support for analyzing the evolution of the mechanical properties of cured materials, regulating the curing stress, and optimizing the mechanical properties of cured products.

[0021] Second, the present invention couples the curing stress acquisition module and the reaction temperature acquisition module to achieve simultaneous and synchronous testing of the material curing stress and reaction temperature in light, heat, and light-heat coupled curing reactions, providing the curing reaction with real-time evolution of mechanical properties along with curing dynamics; at the same time, the simultaneous and synchronous testing of multiple parameters can not only avoid the influence of different sample sizes, test conditions, and sampling rates on the experimental results when each parameter is tested separately, as well as the difficulties caused by data coupling analysis; in addition, obtaining multiple sets of data through a set of experiments greatly saves test time and resources, and improves test efficiency and reliability; the real-time coupled evolution data guides and regulates the curing dynamics to optimize the mechanical properties of the cured product, which has important guidance and economic significance for the practical application of curing materials in various industries.

[0022] Third, the present invention optimizes the mechanical properties of the cured product by guiding and controlling the curing dynamics through real-time coupled evolution data, which has important guidance and economic significance for the practical application of light / heat / light-heat coupling materials in various industries.

[0023] Fourth, the present invention achieves the coupling of a thickness control module, a stiffness adjustment module, a curing stress acquisition module, and a reaction temperature acquisition module. This allows for simultaneous measurement of multiple parameters, such as curing stress and reaction temperature, under varying thickness and stiffness conditions during light-curing, thermal curing, and light-thermal coupled curing reactions. This testing method provides real-time coupled dynamic data on mechanical and temperature parameters, providing strong support for curing reactions.

[0024] Fifth, existing photocuring testing technologies suffer from low measurement accuracy, inability to characterize the complete curing process, high measurement costs, and potential impact on the intrinsic curing of samples. Existing thermal curing technologies suffer from a lack of real-time detection, large measurement errors, and equipment complexity. Existing photo-thermal coupling curing technology, a simple combination of photo- and thermal-curing testing methods, can present issues such as data conflicts due to differences in photo- and thermal-curing methods, multi-physics coupling interference, dynamic response and resolution limitations, and high equipment integration complexity. Furthermore, existing testing methods and equipment are difficult to apply to both photo- and thermal-curing testing conditions.

[0025] The present invention proposes coupling a thickness control module, an ambient temperature control module, and a curing light source control module to achieve control of complex curing conditions involving light, heat, and light-heat coupling. Simultaneously, by coupling a curing stress acquisition module with a reaction temperature acquisition module, a curing dynamic testing platform based on a temperature control box, a curing light source, an electric displacement platform, and a cantilever beam system has been developed. This system can accurately measure uniaxial curing stress under light-curing, heat-curing, or light-heat coupling curing conditions by monitoring cantilever deflection, while the electric displacement platform can precisely control the thickness of the curing material. Verification tests have confirmed the reliability and accuracy of the device under various curing conditions, providing new insights into stress development during the curing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 This is a schematic structural diagram of a curing stress testing device suitable for light, heat and coupled curing provided in an embodiment of the present application; Figure 2 A schematic structural diagram of a curing stress testing device suitable for light, heat and coupled curing provided in one embodiment of the present application; Figure 3A flowchart of a curing stress optimization process provided in one embodiment of the present application; Figure 4 A flow chart of a curing stress testing method applicable to light, heat, and coupled curing provided in one embodiment of the present application; Figure 5 A schematic diagram illustrating the testing principle of cantilever beam deflection according to an embodiment of the present application; Figure 6 A schematic diagram of test results of curing stress under light curing provided in one embodiment of the present application; Figure 7 A schematic diagram of test results of curing stress under thermal curing provided in one embodiment of the present application; Figure 8 A schematic diagram of the test results of curing stress under light-heat coupling curing provided in one embodiment of the present application. DETAILED DESCRIPTION

[0028] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0029] See also Figure 1 and Figure 2 , is a structural diagram of a curing stress testing device suitable for light, heat and coupled curing provided in one embodiment of the present application, comprising: A curing stress acquisition module is used to obtain the curing stress of the sample during the curing reaction in real time; A reaction temperature acquisition module is used to obtain the reaction temperature of the sample during the curing reaction in real time; Sample thickness adjustment module, used to adjust the thickness of the sample; A stiffness adjustment module is used to adjust the constraint stiffness of the sample during the reaction; An environmental temperature control module, used to control the reaction temperature during the thermal curing reaction; Curing light source control module, used to control the lighting conditions in the light curing reaction; The acquisition module is connected to the curing stress acquisition module and the reaction temperature acquisition module, and is used to adjust the acquisition time and frequency of the curing stress and / or reaction temperature to achieve simultaneous synchronous acquisition of the curing stress and reaction temperature.

[0030] In one example, the curing stress acquisition module includes: cantilever beam; The first data acquisition unit includes a capacitive displacement sensor at the end of the cantilever beam, which is used to collect the deflection of the end of the cantilever beam caused by the force generated by the curing of the sample during the curing reaction and the corresponding time; a first data processing unit, configured to plot the data collected by the first data collection unit into a displacement-time curve; The curing stress calculation unit is used to calculate the curing stress of the sample at each time point during the reaction process based on the displacement-time curve and the sample mechanical beam theory, after correcting the shear stress, and fully depict the dynamic evolution process of the curing stress.

[0031] In one example, the reaction temperature acquisition module includes: Thermocouple temperature sensor system; The second data acquisition unit is used to collect the potential of the thermocouple wire during the curing reaction; a second data processing unit, for converting the electric potential into a real-time temperature during the curing reaction; The reaction temperature calculation unit is used to convert the temperature into the real-time temperature of the sample through a calculator.

[0032] In one example, the sample thickness adjustment module includes: The three-axis displacement platform system is used to clamp the sample and drive the sample to move; wherein, a lower glass rod is fixed in the three-axis displacement platform, an upper glass rod is fixed on the cantilever beam, and the sample is fixed by the upper and lower glass rods.

[0033] The first control unit is used to control the movement of the three-axis displacement platform in the X, Y, and Z directions; The third data acquisition unit, the capacitive displacement sensor inside the platform, is used to collect the displacement in the Z direction during the movement of the platform.

[0034] In one example, the stiffness adjustment module includes: Cantilever beam (the stiffness adjustment module and the curing stress acquisition module share the same cantilever beam); A second control unit is used to adjust cantilever beams of different sizes and materials; The third control unit is used to adjust the position of the clamp on the cantilever beam.

[0035] In one example, the ambient temperature control module includes: Temperature box, used to provide temperature environment for samples; A fourth control unit, used to control the set temperature of the environment in which the sample is located; The fourth data acquisition unit includes a thermocouple temperature sensor disposed inside the temperature box, and is used to acquire the actual temperature inside the temperature box.

[0036] In one example, the curing light source control module includes: UV-LED curing light source, used to provide a light source environment for the sample; The fifth control unit is used to control the irradiation intensity and irradiation time of the curing light.

[0037] In one example, the first to fifth control units constitute a control module.

[0038] In one example, the curing stress testing device suitable for light, heat and coupled curing further includes: The optimization module is used to adjust the reaction conditions and / or sample components in the curing reaction according to the obtained curing stress, so as to optimize the curing stress of the sample.

[0039] Figure 3 A flowchart of a curing stress optimization process provided in one embodiment of the present application.

[0040] Figure 4 This is a flow chart of a curing stress testing method applicable to light, heat, and coupled curing, provided in one embodiment of the present application. It includes: S101 , filling a sample into a sample thickness adjustment module, adjusting the sample thickness according to the sample thickness adjustment module, and adjusting the constraint stiffness of the sample through the stiffness adjustment module.

[0041] S102 : According to the curing conditions, the temperature conditions and the light source conditions are set by the environment temperature control module and / or the curing light source control module.

[0042] S103 , obtaining the curing stress and reaction temperature of the sample through the acquisition module, the curing stress acquisition module and the reaction temperature acquisition module.

[0043] In one example, the process of obtaining the curing stress includes: The first step is to collect the force generated by the curing of the sample during the curing reaction and convert it into a concentrated force acting on the cantilever beam through the screw of the upper clamp, causing the displacement of the end of the cantilever beam and the corresponding time; The second step is to plot the collected data into a displacement-time curve; The third step is to calculate the curing stress of the material and its dynamic development process during the curing reaction based on the displacement-time curve, beam theory of material mechanics and shear stress correction.

[0044] In one example, the curing stress σ of the material during the curing reaction is obtained from the deflection δ by determining the deflection change of the cantilever beam system caused by the sample; the formula is as follows:

[0045] Where, and are the elastic modulus of the cantilever beam system and the moment of inertia of the beam section, respectively; is the length of the cantilever beam system; is the distance from the sample to the fixed end; is the Poisson's ratio of the beam material; is the sample surface area; Indicates deflection.

[0046] In one example, the process of taking the temperature includes: The first step is to collect the real-time thermocouple wire potential during the curing reaction; The second step is to convert the electric potential into the real-time temperature during the curing reaction; The third step is to plot the collected data into a temperature-time curve.

[0047] In another embodiment provided in the present application, the process of obtaining the curing stress includes: Step 1: Use the sample thickness adjustment module to adjust the gap between the upper and lower glass rods to the required height, adjust the corresponding constraint stiffness, and fill the sample in the gap between the upper and lower glass rods.

[0048] Step 2: According to the corresponding curing conditions, the ambient temperature control module and / or the curing light source control module are adjusted, and the sample and parts of the upper and lower glass rods are placed in a temperature chamber. The curing light source is vertically aligned with the lower glass rod, and the material is in contact with the upper glass rod. The curing stress is transmitted to the cantilever beam. The capacitive sensor at the end of the cantilever beam measures the displacement of the beam end and derives the curing stress of the material. A thermocouple wire is placed in the sample to measure the reaction temperature of the material. Step three: directly connect the ambient temperature control module, light source control module, and cantilever beam system to the computer, and use LabVIEW self-written program to achieve real-time control of lighting conditions and temperature conditions; by adjusting the sampling frequency and time of the data acquisition card, simultaneous and synchronous data acquisition is achieved.

[0049] Figures 6 to 8 This is an experimental data graph provided for this application.

[0050] The experimental process is as follows: First, experimental material selection The experimental material used for light curing in this article is a UV-curable polyurethane acrylate (PUA) system, a comprehensive oligomer made by reacting the hydroxyl groups of a long-chain diol and a hydroxy acrylate with an isocyanate. The PUA molecular structure contains both acrylic functional groups and urethane bonds, giving the fully cured product high abrasion resistance, adhesion, flexibility, and excellent low-temperature resistance.

[0051] The experimental material for thermal curing is an epoxy resin system. This system is a direct addition or epoxy ring-opening polymerization reaction between epoxy resin and curing agent. No water or volatile by-products are released, and shrinkage is low during the curing process. At the same time, it has good load-bearing capacity and elastic modulus.

[0052] The experimental material for light-thermal coupled curing is an acrylate system. The photoinitiator and thermal initiator in this system can generate free radicals under light and heat conditions, respectively, triggering the polymerization reaction of the double bonds in the acrylate monomer to form a cured network with a cross-linked structure. This dual-light and thermal curing mode enables the acrylate system material to break through the limitations of light curing depth and shape during the curing process. It is suitable for objects with complex shapes, thick coatings, and colored coatings that are difficult to achieve complete curing through single light curing. At the same time, this dual curing mechanism also improves the overall performance of the material, such as hardness, adhesion, flexibility, water resistance, and heat resistance.

[0053] The main experimental instrument is the curing stress testing device provided in this application, which is suitable for light, heat and their coupled curing.

[0054] Among them, the curing stress test is mainly carried out using a cantilever beam: the deflection δ at the end of the cantilever beam is measured by a high-precision capacitive sensor, and the relationship between the concentrated force F and the deflection δ at the end of the beam is obtained through the beam theory of material mechanics:

[0055] Where, and are the elastic modulus of the cantilever beam system and the moment of inertia of the beam section, respectively; is the length of the cantilever beam system; is the distance from the sample to the fixed end; is the Poisson's ratio of the beam material; Represents deflection, measured by a displacement sensor.

[0056] like Figure 5 As shown. In the experimental device, the cantilever beam is a slender beam ( ), but in the calculation process, there is no load on the beam from point O to the end of the beam, so the actual calculated length of the beam is .when When it is large, the shear stress will have a greater impact on the deflection, so it needs to be corrected; the correction formula is:

[0057] Where, is the shear correction factor, and the rectangular section is , is the shear modulus , is the Poisson's ratio of the beam material.

[0058] The relationship between the corrected curing stress and the beam end deflection becomes:

[0059] Where, is the surface area of ​​the sample; r is the radius of the sample.

[0060] Thermocouples are commonly used temperature measuring components in temperature measuring instruments. They directly measure temperature and convert the temperature signal into a thermoelectric potential signal, which is then converted into the temperature of the measured medium through an electrical instrument (secondary instrument). The appearance of various thermocouples often varies greatly depending on the needs, but their basic structure is roughly the same. They usually consist of a thermode, an insulating protective tube, and a junction box. They are usually used in conjunction with display instruments, recording instruments, and electronic regulators.

[0061] like Figure 2 As shown, the three-axis displacement platform is used to adjust the gap between the upper and lower glass rods; the curing light source is transmitted to the material through the lower glass rod, and a constant heating temperature is provided to the material by placing the sample area inside the temperature box. The material contacts the upper glass rod and transmits the curing stress to the cantilever beam. The capacitive sensor at the end of the cantilever beam measures the displacement of the end of the beam, and then derives the curing stress of the material; an extremely fine thermocouple wire is placed in the sample to measure the reaction temperature of the material; finally, the curing light source control system, temperature box control system, cantilever beam system, and thermocouple system are directly connected to the computer, and a self-written LabVIEW program is used to realize real-time control of light / heat / light-heat coupling curing conditions. By adjusting the sampling time and frequency of the cantilever beam system and the thermocouple system, the data of the two can be collected simultaneously.

[0062] Dynamic multi-parameter evolution of polymerization and material performance optimization: Based on the above test results of curing stress and temperature, the mechanical properties of the polymer product were optimized. Specific optimization schemes include: changing the illumination conditions (such as changing the illumination intensity, illumination time, controlling the illumination intensity in different time periods, and using intermittent illumination, etc.) and / or temperature conditions (such as changing the heating temperature, heating time, temperature rise time, and cooling time, etc.) and / or adjusting the system components (such as changing the concentration of the initiator, the ratio of the curing system, adding fillers, etc.). The experimental results are as follows: Figures 6 to 8 shown.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A curing stress testing device suitable for light, heat and their coupled curing, characterized in that: include: A curing stress acquisition module is used to obtain the curing stress of the sample during the curing reaction in real time; A reaction temperature acquisition module is used to obtain the reaction temperature of the sample during the curing reaction in real time; Sample thickness adjustment module, used to adjust the thickness of the sample; A stiffness adjustment module is used to adjust the constraint stiffness of the sample during the reaction; An environmental temperature control module, used to control the reaction temperature during the thermal curing reaction; Curing light source control module, used to control the lighting conditions in the light curing reaction; The acquisition module is connected to the curing stress acquisition module and the reaction temperature acquisition module, and is used to adjust the acquisition time and frequency of the curing stress and / or reaction temperature to achieve simultaneous synchronous acquisition of the curing stress and reaction temperature.

2. The curing stress testing device suitable for light, heat and their coupled curing according to claim 1, characterized in that: The curing stress acquisition module includes: cantilever beam; The first data acquisition unit includes a capacitive displacement sensor at the end of the cantilever beam, which is used to collect the deflection of the end of the cantilever beam caused by the force generated by the curing of the sample during the curing reaction and the corresponding time; a first data processing unit, configured to plot the data collected by the first data collection unit into a displacement-time curve; The curing stress calculation unit is used to calculate the curing stress of the sample at each time point during the reaction process based on the displacement-time curve and the sample mechanical beam theory, after correcting the shear stress, and fully depict the dynamic evolution process of the curing stress.

3. The curing stress testing device suitable for light, heat and their coupled curing according to claim 1, characterized in that: The reaction temperature acquisition module includes: Thermocouple temperature sensor system; The second data acquisition unit is used to collect the potential of the thermocouple wire during the curing reaction; a second data processing unit, for converting the electric potential into a real-time temperature during the curing reaction; The reaction temperature calculation unit is used to convert the temperature into the real-time temperature of the sample through a calculator.

4. The curing stress testing device suitable for light, heat and their coupled curing according to claim 1, characterized in that: The sample thickness adjustment module includes: Three-axis displacement platform system, used to clamp samples and drive them to move; The first control unit is used to control the movement of the three-axis displacement platform in the X, Y, and Z directions; The third data acquisition unit, the capacitive displacement sensor inside the platform, is used to collect the displacement in the Z direction during the movement of the platform.

5. The curing stress testing device applicable to light, heat and their coupled curing according to claim 1, characterized in that: The stiffness adjustment module includes: cantilever beam; A second control unit is used to adjust cantilever beams of different sizes and materials; The third control unit is used to adjust the position of the clamp on the cantilever beam.

6. The curing stress testing device applicable to light, heat and their coupled curing according to claim 1, characterized in that: The ambient temperature control module includes: Temperature box, used to provide temperature environment for samples; A fourth control unit, used to control the set temperature of the environment in which the sample is located; The fourth data acquisition unit includes a thermocouple temperature sensor disposed inside the temperature box, and is used to acquire the actual temperature inside the temperature box.

7. The curing stress testing device applicable to light, heat and their coupled curing according to claim 1, characterized in that: The curing light source control module includes: UV-LED curing light source, used to provide a light source environment for the sample; The fifth control unit is used to control the irradiation intensity and irradiation time of the curing light.

8. The curing stress testing device suitable for light, heat and their coupled curing according to any one of claims 1 to 7, characterized in that: The curing stress testing device suitable for light, heat and coupled curing also includes: The optimization module is used to adjust the reaction conditions and / or sample components in the curing reaction according to the obtained curing stress, so as to optimize the curing stress of the sample.

9. A curing stress testing method suitable for light, heat and their coupled curing, characterized in that: The device according to any one of claims 1 to 8, comprising: Filling the sample into the sample thickness adjustment module, and adjusting the sample thickness according to the sample thickness adjustment module, and adjusting the constraint stiffness of the sample through the stiffness adjustment module; According to the curing conditions, the temperature conditions and light source conditions are set through the ambient temperature control module and / or the curing light source control module; The curing stress and reaction temperature of the sample are obtained through the acquisition module, the curing stress acquisition module and the reaction temperature acquisition module.

10. The curing stress testing method applicable to light, heat and their coupled curing according to claim 9, characterized in that: By determining the deflection change of the cantilever beam system caused by the sample, the curing stress σ of the material in the curing reaction is obtained from the deflection δ; the formula is as follows: Where, and are the elastic modulus of the cantilever beam system and the moment of inertia of the beam section, respectively; is the length of the cantilever beam system; is the distance from the sample to the fixed end; is the Poisson's ratio of the beam material; is the sample surface area; Indicates deflection.

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