High-pressure vulcanization process for rubber roller

Abstract

The invention discloses a rubber roller high-pressure vulcanization process, and relates to the field of rubber roller manufacturing. Comprising the following steps: S1, treating a rubber material by adopting a supercritical fluid assisted degassing process; s2, pre-vulcanization is conducted through a pulse high-pressure vulcanization technology, then the pressure is increased to 6 MPa to 10 MPa at the speed of 0.1 MPa / s to 0.5 MPa / s, and dynamic pressure adjustment is conducted at the interval of 30 s / s to 90 s / cycle; s3, carrying out rapid vulcanization for 5-20 minutes by adopting a high-energy density instantaneous heating process and an electromagnetic induction mode; s4, an intelligent temperature gradient control technology is adopted, in the vulcanization process, the temperature difference of 10-30 DEG C is formed, and gradual balance is conducted within 10-60 minutes; and S5, carrying out heat treatment on the vulcanized rubber roller in an environment of 60-100 DEG C for 3-12 hours by adopting a metastable state annealing process. The method has the beneficial effects that by optimizing the degassing, vulcanizing, heating, temperature control and annealing processes, the compactness, crosslinking uniformity, dimensional stability and wear resistance of the rubber roller are improved, meanwhile, the vulcanizing time is shortened, and the defect rate is reduced.

Description

Technical Field

[0001] The present invention relates to the field of rubber roller manufacturing, and more specifically, to a high-pressure vulcanization process for rubber rollers. Background Art

[0002] The development of a high-pressure vulcanization process for rubber rollers has gone through multiple stages, gradually achieving precise control of the vulcanization process to improve the performance and service life of rubber rollers. The early rubber roller vulcanization process mainly relied on traditional static vulcanization methods, which carried out vulcanization under constant temperature and pressure conditions. However, this method is prone to uneven vulcanization. Especially during mass production, the temperature difference between the inner and outer layers of the rubber roller is relatively large, resulting in uneven vulcanization, generating internal stress and performance fluctuations. With the development of technology, high-efficiency processes such as pulse high-pressure vulcanization and instantaneous heating have been introduced, gradually solving the problems of long vulcanization time and low energy efficiency, and significantly improving the vulcanization efficiency and quality of rubber rollers.

[0003] In the prior art, the combination of pulse high-pressure vulcanization process and instantaneous heating technology has, to a certain extent, improved the vulcanization uniformity of rubber rollers, and through optimized temperature gradient control and pressure fluctuations, defects such as bubbles and inclusions during the vulcanization process have been effectively alleviated. However, there are still some deficiencies. First, the problem of uneven vulcanization in traditional vulcanization processes still exists. Especially for the control of the density inside the rubber roller, it is relatively poor, making it difficult to completely avoid defects such as bubbles and inclusions. In addition, in the prior art, due to the strong conditions of high temperature and high pressure, the rubber compound is prone to excessive degassing, which in turn affects the stability of the cross-linked structure after vulcanization and leads to excessive internal stress, which has a negative impact on the long-term use performance of rubber rollers. Summary of the Invention

[0004] The purpose of the present invention is to provide a high-pressure vulcanization process for rubber rollers to solve the problems raised in the above background art: First, the problem of uneven vulcanization in traditional vulcanization processes still exists. Especially for the control of the density inside the rubber roller, it is relatively poor, making it difficult to completely avoid defects such as bubbles and inclusions. In addition, in the prior art, due to the strong conditions of high temperature and high pressure, the rubber compound is prone to excessive degassing, which in turn affects the stability of the cross-linked structure after vulcanization and leads to excessive internal stress, which has a negative impact on the long-term use performance of rubber rollers.

[0005] Technical Solution: It includes the following steps: S1. Adopt a supercritical fluid-assisted degassing process, and introduce supercritical N2 at a pressure of 5 MPa to 10 MPa and a temperature of 35 °C to 60 °C to process the rubber compound for 1 - 10 minutes; S2. Adopt the pulse high-pressure vulcanization process, carry out pre-vulcanization at an initial pressure of 2 MPa to 5 MPa, then increase the pressure to 6 MPa to 10 MPa at a rate of 0.1 - 0.5 MPa / s, and perform dynamic pressure adjustment at intervals of 30 - 90 seconds / cycle; S3. Adopt the high-energy density instantaneous heating process, and carry out rapid vulcanization of the rubber compound for 5 - 20 minutes by electromagnetic induction within the temperature range of 150 °C to 250 °C; S4. Adopt the intelligent temperature gradient control process. During the vulcanization process, the temperature of the external area is controlled at 120 °C to 180 °C, and the temperature of the internal area is controlled at 140 °C to 200 °C, forming a temperature difference of 10 - 30 °C, and gradually balance within 10 - 60 minutes; S5. Adopt the metastable annealing process, and carry out heat treatment of the vulcanized rubber roller in an environment of 60 °C to 100 °C for 3 - 12 hours.

[0006] Preferably, during the supercritical fluid-assisted degassing process in step S1, the flow rate of the supercritical CO 2 is controlled at 5 - 50 mL / min, and the pressure fluctuates periodically within the range of 6 - 9 MPa.

[0007] Preferably, during the pulse high-pressure vulcanization process in step S2, the frequency of the pressure periodic adjustment is controlled at 0.05 - 0.5 Hz, and the pressure fluctuation amplitude of each cycle does not exceed 30%.

[0008] Preferably, the instantaneous heating process in step S3 adopts a high-frequency electromagnetic induction source, and the heating power is controlled at 5 - 50 kW / m².

[0009] Preferably, during the intelligent temperature gradient control process in step S4, the external temperature decreases by 0.5 - 2 °C per minute, and the internal temperature decreases by 1 - 3 °C per minute to gradually balance the internal and external temperature differences.

[0010] Preferably, the metastable annealing process in step S5 is carried out in an inert gas environment.

[0011] Compared with the prior art, the advantages of the present invention are as follows: Adopt the supercritical fluid-assisted degassing process, carry out dynamic pressure regulation in a high-pressure supercritical N 2 or CO 2 environment, effectively remove the dissolved gases and minute inclusions in the rubber compound. Compared with the traditional vacuum degassing process, the degassing efficiency is improved, and the problem of bubble residues during the vulcanization process is avoided.

[0012] Adopt the pulse high-pressure vulcanization process, and through dynamic pressure adjustment, make the vulcanization process more stable, ensure the crosslinking uniformity, and avoid the problems of local over-vulcanization or under-vulcanization caused by the traditional constant high-pressure vulcanization.

[0013] Adopt a high-energy density instantaneous heating process, use high-frequency electromagnetic induction to rapidly increase the temperature, make the rubber compound evenly heated, and complete vulcanization in a short time. Compared with the traditional electrothermal vulcanization process, the heating efficiency is higher, the vulcanization time is greatly shortened, and the production efficiency is improved.

[0014] Adopt an intelligent temperature gradient control process to form a certain temperature difference during vulcanization, and gradually balance the internal and external temperatures, reducing the thermal stress caused by sudden temperature changes, thereby reducing the residual stress inside the rubber roller and improving the dimensional stability and service life.

[0015] (5) Adopt a metastable annealing process, perform low-temperature heat treatment after vulcanization to further optimize the cross-linked structure, and at the same time reduce the oxidation effect in an inert gas environment. Compared with traditional natural cooling or rapid cooling, the wear resistance and mechanical properties of the rubber roller are improved. Brief Description of the Drawings

[0016] Figure 1 It is a schematic diagram of the overall system of a high-pressure vulcanization process for a rubber roller according to the present invention. Detailed Embodiments Embodiment

[0017] Examples 1-3 Example 1: S1. Adopt a supercritical fluid-assisted degassing process, introduce supercritical N2 at a pressure of 5 MPa to 10 MPa and a temperature of 35 °C to 60 °C, and treat the rubber compound for 1-10 minutes; S2. Adopt a pulsed high-pressure vulcanization process, perform pre-vulcanization at an initial pressure of 2 MPa to 5 MPa, then increase the pressure to 6 MPa to 10 MPa at a rate of 0.1-0.5 MPa / s, and perform dynamic pressure adjustment at intervals of 30-90 seconds / cycle; S3. Adopt a high-energy density instantaneous heating process to rapidly vulcanize the rubber compound for 5-20 minutes by electromagnetic induction within a temperature range of 150 °C to 250 °C; S4. Adopt an intelligent temperature gradient control process. During vulcanization, the temperature of the external region is controlled at 120 °C to 180 °C, and the temperature of the internal region is controlled at 140 °C to 200 °C, forming a temperature difference of 10-30 °C, and gradually balancing within 10-60 minutes; S5. Adopt a metastable annealing process to perform heat treatment on the vulcanized rubber roller in an environment of 60 °C to 100 °C for 3-12 hours.

[0018] During the supercritical fluid-assisted degassing process in step S1, the flow rate of the introduced supercritical CO 2 is controlled at 5-50 mL / min, and the pressure fluctuates periodically within the range of 6-9 MPa.

[0019] During the pulse high - voltage vulcanization process in step S2, the frequency of pressure cycle adjustment is controlled at 0.05 - 0.5 Hz, and the pressure fluctuation amplitude in each cycle does not exceed 30%.

[0020] The instantaneous heating process in step S3 uses a high - frequency electromagnetic induction source, and the heating power is controlled at 5 - 50 kW / m².

[0021] During the intelligent temperature gradient control process in step S4, the external temperature decreases by 0.5 - 2 °C per minute, and the internal temperature decreases by 1 - 3 °C per minute to gradually balance the internal and external temperature differences.

[0022] The metastable annealing process in step S5 is carried out in an inert gas environment.

[0023] Example 2. The difference from Example 1 is that the specific process parameters are adjusted as follows: S1. Supercritical fluid - assisted degassing process, using supercritical N 2 , with a pressure of 7 MPa, a temperature of 45 °C, a treatment time of 7 minutes, a flow rate of 20 mL / min, and a pressure periodic fluctuation range of 6 - 8 MPa.

[0024] S2. Pulse high - voltage vulcanization process, with an initial pressure of 3 MPa, a pressure rising rate of 0.4 MPa / s, a maximum pressure of 9 MPa, a pressure cycle adjustment frequency of 0.3 Hz, and a pressure fluctuation amplitude of 30%.

[0025] S3. High - energy - density instantaneous heating process, using a high - frequency electromagnetic induction source, with a heating power of 30 kW / m², a temperature range of 160 °C to 220 °C, and a heating time of 18 minutes.

[0026] S4. Intelligent temperature gradient control process, with the external area temperature controlled at 130 °C, the internal area temperature controlled at 160 °C, a temperature difference of 30 °C, and gradually balanced within 60 minutes.

[0027] S5. Metastable annealing process, with heat treatment carried out in an argon environment, an annealing temperature of 90 °C, and a treatment time of 10 hours.

[0028] Implementation effect: The degassing effect is good, the surface of the rubber roller is smooth, there are no bubble inclusions, and the cross - linking effect is uniform.

[0029] Through intelligent temperature control, the thermal stress during the vulcanization process is effectively reduced, and the dimensional stability of the rubber roller is significantly improved.

[0030] Example 3: The difference from Example 1 is that the specific process parameters are adjusted as follows: S1. Supercritical fluid - assisted degassing process, using supercritical N 2, the pressure is 6 MPa, the temperature is 55 °C, the treatment time is 6 minutes, the flow rate is 40 mL / min, and the periodic pressure fluctuation range is 5 - 7 MPa.

[0031] S2. Pulse high-pressure vulcanization process, the initial pressure is 2.5 MPa, the pressure increase rate is 0.2 MPa / s, the maximum pressure is 7 MPa, the pressure cycle adjustment frequency is 0.1 Hz, and the pressure fluctuation amplitude is 20%.

[0032] S3. High-energy density instantaneous heating process, using a high-frequency electromagnetic induction source, the heating power is 50 kW / m², the temperature range is 200 °C to 250 °C, and the heating time is 12 minutes.

[0033] S4. Intelligent temperature gradient control process, the external area temperature is controlled at 160 °C, the internal area temperature is controlled at 180 °C, the temperature difference is 20 °C, and it is gradually balanced within 30 minutes.

[0034] S5. Metastable annealing process, heat treatment is carried out in a nitrogen environment, the annealing temperature is 75 °C, and the treatment time is 9 hours.

[0035] Examples 4 - 6 Example 4: The difference from Example 1 is that the specific process parameters are adjusted as follows: S1. Supercritical fluid-assisted degassing: Using supercritical CO 2 , the pressure is 8 MPa, the temperature is 50 °C, the flow rate is 30 mL / min, and the treatment time is 8 minutes; S2. Pulse high-pressure vulcanization: The initial pressure is 4 MPa, and it is increased to 8 MPa at a rate of 0.2 MPa / s, and the dynamic pressure adjustment frequency is 0.2 Hz; S3. Instantaneous heating vulcanization: Using high-frequency electromagnetic induction, the heating power is 20 kW / m², the vulcanization temperature is 200 °C, and the vulcanization time is 12 minutes; S4. Intelligent temperature gradient control: The external temperature is 160 °C, the internal temperature is 190 °C, the temperature difference is 20 °C, and it is balanced within 30 minutes; S5. Metastable annealing: The annealing temperature is 80 °C, the time is 8 hours, and it is carried out in a nitrogen environment.

[0036] Example 5: The difference from Example 1 is that the specific process parameters are adjusted as follows: S1. Supercritical fluid-assisted degassing: Using supercritical N 2 , the pressure is 9 MPa, the temperature is 45 °C, the flow rate is 40 mL / min, and the treatment time is 10 minutes; S2. Pulse high-pressure vulcanization: The initial pressure is 5 MPa, and it is increased to 10 MPa at a rate of 0.3 MPa / s, and the dynamic pressure adjustment frequency is 0.3 Hz; S3. Instantaneous heating vulcanization: Using high-frequency electromagnetic induction, the heating power is 30 kW / m², the vulcanization temperature is 210 °C, and the vulcanization time is 10 minutes; S4. Intelligent temperature gradient control: The external temperature is 150 °C, the internal temperature is 180 °C, the temperature difference is 15 °C, and it is balanced within 45 minutes; S5. Metastable annealing: The annealing temperature is 90 °C, the time is 10 hours, and it is carried out in a nitrogen environment.

[0037] Example 6: The difference from Example 1 is that the specific process parameters are adjusted as follows: S1. Supercritical fluid-assisted degassing: Using supercritical CO 2 , the pressure is 7 MPa, the temperature is 55 °C, the flow rate is 25 mL / min, and the treatment time is 7 minutes; S2. Pulsed high-pressure vulcanization: The initial pressure is 3 MPa, which is increased to 9 MPa at a rate of 0.4 MPa / s, and the dynamic pressure adjustment frequency is 0.15 Hz; S3. Instantaneous heating vulcanization: Using high-frequency electromagnetic induction, the heating power is 25 kW / m², the vulcanization temperature is 190 °C, and the vulcanization time is 15 minutes; S4. Intelligent temperature gradient control: The external temperature is 170 °C, the internal temperature is 200 °C, the temperature difference is 25 °C, and it is balanced within 40 minutes; S5. Metastable annealing: The annealing temperature is 85 °C, the time is 7 hours, and it is carried out in a nitrogen environment.

[0038] Comparative example Comparative example 1 The process parameters are as follows: S1. Traditional vacuum degassing process, carried out at room temperature for 10 minutes, the pressure is controlled at 0.1 MPa, and supercritical fluid-assisted degassing is not used.

[0039] S2. Constant high-pressure vulcanization process, the pressure is set at 8 MPa, the vulcanization time is 60 minutes, and there is no dynamic pressure fluctuation.

[0040] S3. Traditional electric heating process, using a traditional heating furnace, the temperature is 180 °C, and the heating time is 40 minutes.

[0041] S4. Without temperature gradient control, the temperature remains constant at 170 °C throughout the vulcanization process.

[0042] S5. The annealing process is not carried out, and only conventional cooling treatment is carried out.

[0043] Implementation effect. The degassing effect is poor, bubbles or impurities are likely to appear on the surface of the rubber compound, and the cross-linking effect is uneven.

[0044] The internal stress of the rubber roller is large, problems such as cracking and deformation are likely to occur, and the strength of the rubber roller is low.

[0045] Comparative Example 2: S1. Supercritical fluid-assisted degassing process, using supercritical N 2 , with a pressure of 6 MPa, a temperature of 40 °C, a treatment time of 5 minutes, a flow rate of 30 mL / min, and no periodic pressure fluctuations.

[0046] S2. Pulsed high-pressure vulcanization process, with an initial pressure of 4 MPa, a pressure increase rate of 0.5 MPa / s, a maximum pressure of 8 MPa, and no periodic pressure adjustment.

[0047] S3. High-energy density instantaneous heating process, using a high-frequency electromagnetic induction source, a heating power of 45 kW / m², a temperature range of 180 °C to 230 °C, and a heating time of 20 minutes.

[0048] S4. Intelligent temperature gradient control process, with the external region temperature controlled at 140 °C, the internal region temperature controlled at 190 °C, a temperature difference of 50 °C, and gradually balanced within 45 minutes.

[0049] S5. Metastable annealing process, with heat treatment carried out in an argon environment, an annealing temperature of 90 °C, and a treatment time of 8 hours.

[0050] Comparative Example 3: S1. Supercritical fluid-assisted degassing: Using supercritical CO 2 , with a pressure of 8 MPa, a temperature of 50 °C, a flow rate of 30 mL / min, and a treatment time of 8 minutes; S2. Pulsed high-pressure vulcanization: An initial pressure of 4 MPa, increased to 8 MPa at a rate of 0.2 MPa / s, and a dynamic pressure adjustment frequency of 0.2 Hz; S3. Instantaneous heating vulcanization: Using high-frequency electromagnetic induction, a heating power of 20 kW / m², a vulcanization temperature of 200 °C, and a vulcanization time of 12 minutes; S4. Intelligent temperature gradient control: An external temperature of 160 °C, an internal temperature of 190 °C, a temperature difference of 20 °C, and balanced within 30 minutes; S5. Metastable annealing process not used: Direct cooling after vulcanization.

[0051] Comparative Example 4: S1. Supercritical fluid-assisted degassing: Using traditional vacuum degassing, with a pressure of 0.1 MPa and a time of 15 minutes; S2. Pulsed high-pressure vulcanization: An initial pressure of 4 MPa, increased to 8 MPa at a rate of 0.2 MPa / s, and a dynamic pressure adjustment frequency of 0.2 Hz; S3. Instantaneous heating vulcanization: Using high-frequency electromagnetic induction, a heating power of 20 kW / m², a vulcanization temperature of 200 °C, and a vulcanization time of 12 minutes; S4. Intelligent temperature gradient control: external temperature 160℃, internal temperature 190℃, temperature difference 20℃, equilibrium within 30 minutes; S5. Metastable annealing: annealing temperature 80°C, time 8 hours, carried out in a nitrogen environment.

[0052] Result: There are many bubbles on the surface of the rubber roller, the inclusions cannot be completely eliminated, and the local vulcanization is uneven.

[0053] Comparative Example 5: S1. Supercritical fluid assisted degassing: using supercritical N 2 , pressure 9 MPa, temperature 45 °C, flow rate 40 mL / min, treatment time 10 minutes; S2. Vulcanization method: traditional constant high pressure vulcanization, pressure 10MPa, duration 15 minutes; S3. Instantaneous heating vulcanization: using high-frequency electromagnetic induction, heating power 30kW / m², vulcanization temperature 210℃, vulcanization time 10 minutes; S4. Intelligent temperature gradient control: external temperature 150℃, internal temperature 180℃, temperature difference 15℃, equilibrium within 45 minutes; S5. Metastable annealing: annealing temperature is 90°C, time is 10 hours, and it is carried out in a nitrogen environment.

[0054] Result: The internal stress of the rubber roller is relatively large, there is partial under-vulcanization, and the durability is reduced.

[0055] Comparative Example 6: S1. Supercritical fluid assisted degassing: using supercritical CO 2 , pressure 7 MPa, temperature 55 °C, flow rate 25 mL / min, treatment time 7 minutes; S2. Pulse high pressure vulcanization: initial pressure 3MPa, increased to 9MPa at a rate of 0.4MPa / s, dynamic pressure adjustment frequency 0.15Hz; S3. Instantaneous heating vulcanization: using high-frequency electromagnetic induction, heating power 25kW / m², vulcanization temperature 190℃, vulcanization time 15 minutes; S4. Traditional constant temperature vulcanization: the overall temperature is 180°C, and no temperature gradient control is performed; S5. Metastable annealing: annealing temperature 85°C, time 7 hours, carried out in a nitrogen environment.

[0056] In order to determine the difference in density, vulcanization uniformity, and the degree of bubbles and inclusions between the examples and the comparative examples, the following comparative experiment was designed, and the experimental steps are as follows: Preparation of experimental articles: The rubber roller samples prepared in Examples 1-6 were used, 3 in each group, for a total of 18.

[0057] The rubber roller samples prepared in Comparative Examples 1-6 were used, with 3 in each group, for a total of 18.

[0058] Experimental equipment: X-ray microfocus CT scanner (used to measure the content of internal bubbles and inclusions) Electron microscope (used to observe the internal microstructure) Density measuring instrument (used to measure density based on Archimedes' principle) Precision cutting machine (used to cut the rubber roller samples for microscopic analysis) Computer data processing system (used for image processing and data statistical analysis) The experimental steps are as follows: S1. Cut cube specimens with dimensions of 10mm×10mm×10mm from the central area and the edge area of each rubber roller sample. Take 3 sets of specimens for each group of rubber rollers, with a total of 36 sets (18 sets for the examples and 18 sets for the comparative examples).

[0059] S2. Use the X-ray microfocus CT scanner to perform three-dimensional reconstruction on each specimen, measure the volume fraction of internal bubbles and inclusions, and calculate the density.

[0060] The calculation formula is as follows: Density (%) = ( )

[0061] Record and statistically analyze the data.

[0062] S3. Use an electron microscope (SEM) to observe the microstructure of the cut samples, and analyze whether the cross-linking structure is uniform and whether there are obvious bubble defects and inclusions.

[0063] S4. Use a density measuring instrument (based on Archimedes' principle) to measure the density of each group of samples to assist in verifying the density data.

[0064] S5. Statistically analyze the density of each sample, calculate the average value and standard deviation, draw a comparison chart, and analyze the results.

[0065] The experimental data is shown in Table 1:

[0066] Experimental analysis and conclusion: The density of Examples 1-6 is above 98.5%, while the density of Comparative Examples 1-6 is between 93.5% and 94.5%, indicating that the high-pressure vulcanization process of the present invention can significantly improve the density.

[0067] Reduction of bubbles and inclusions: The volume fraction of bubbles in the examples is ≤0.9%, and the volume fraction of inclusions is ≤0.6%. Comparing with the comparative examples (bubbles ≥3.5%, inclusions ≥1.9%), it shows that the present invention can effectively reduce the bubble and inclusion defects during vulcanization.

[0068] Increased density: The density range of the examples is 1.18 - 1.21 g / cm³, significantly higher than that of the comparative examples (1.10 - 1.13 g / cm³), indicating that the process of the present invention can improve the structural compactness of the rubber roller.

[0069] Verification by microscopic observation: Electron microscope observation shows that the cross-linked structure of the examples is more uniform and the number of pores is significantly reduced, while there are still a large number of incompletely eliminated micropores inside the samples of the comparative examples.

[0070] To measure the hardness, tensile strength, and wear resistance of the rubber rollers of the examples and comparative examples, the following comparative experiment was designed, and the experimental steps are as follows: Preparation of experimental items: Vulcanized rubber rollers of Examples 1 - 6, 3 in each group, a total of 18.

[0071] Vulcanized rubber rollers of Comparative Examples 1 - 6, 3 in each group, a total of 18.

[0072] The experimental equipment is as follows: Shore hardness tester (for measuring the hardness of the rubber roller) Electron universal testing machine (for measuring the tensile strength) Wear resistance tester (for evaluating the wear resistance of the rubber roller) Cutting equipment (for preparing standard specimens) The experimental steps are as follows: S1. Using a Shore A hardness tester, measure the hardness at 5 different positions of each sample in an environment of 23°C ± 2°C, and take the average value.

[0073] S2. According to the specification of GB / T528 - 2009 "Determination of Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber", use an electron universal testing machine to conduct a tensile test and measure the tensile strength (MPa).

[0074] S3. Using a DIN wear resistance tester, conduct a wear test on the sample under standard load and friction conditions, and measure the volume wear amount (mm³).

[0075] S4. Statistically analyze the data, calculate the average value and standard deviation, and draw a comparison table.

[0076] The experimental data are shown in Table 2:

[0077] Experimental analysis and conclusion: The hardness range of the examples using the vulcanization process of the present invention is 71.8 - 73.0 Shore A, significantly higher than that of the comparative examples (67.5 - 69.0 Shore A), indicating that this process optimizes the cross-linking density of the rubber roller and improves the hardness.

[0078] Tensile strength increase: The tensile strength of the rubber roller using the vulcanization process of the present invention is 18.2 - 19.0 MPa, which is about 20% higher than that of Comparative Example 14.8 - 15.5 MPa, indicating that the new process can significantly enhance the mechanical strength of the rubber roller and improve its durability.

[0079] Wear resistance improvement: The volume wear of the rubber roller using the vulcanization process of the present invention is 63 - 67 mm³, which is about 23% lower than that of Comparative Example 83 - 88 mm³, indicating that its wear resistance has been greatly improved and it is suitable for high-load working conditions.

[0080] The above shows and describes the basic principles, main features and advantages of the present invention; those skilled in the art should understand that the present invention is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only preferred examples of the present invention and do not limit the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed; the scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. A rubber roller high pressure vulcanization process, characterized in that: The following steps are involved: S1. Using supercritical fluid-assisted degassing process, supercritical N2 is introduced at a pressure of 5MPa to 10MPa and a temperature of 35°C to 60°C to treat the rubber for 1-10 minutes; S2. Using a pulse high pressure vulcanization process, pre-vulcanization is performed at an initial pressure of 2MPa to 5MPa, and then the pressure is increased to 6MPa to 10MPa at a rate of 0.1-0.5MPa / s, and dynamic pressure adjustment is performed at intervals of 30-90 seconds / cycle; S3. Using high energy density instantaneous heating process, the rubber material is rapidly vulcanized in 5-20 minutes by electromagnetic induction at a temperature range of 150℃ to 250℃; S4. Adopt intelligent temperature gradient control process. During the vulcanization process, the temperature of the external area is controlled at 120℃ to 180℃, and the temperature of the internal area is controlled at 140℃ to 200℃, forming a temperature difference of 10-30℃, and gradually balanced within 10-60 minutes; S5. Using the metastable annealing process, the vulcanized rubber roller is heat treated at 60°C to 100°C for 3-12 hours.

2. A rubber roller high pressure vulcanization process according to claim 1, characterized in that: During the supercritical fluid-assisted degassing process of step S1, the flow rate of supercritical CO2 is controlled at 5-50 mL / min, and the pressure fluctuates periodically within the range of 6-9 MPa.

3. A rubber roller high pressure vulcanization process according to claim 1, characterized in that: During the pulse high pressure vulcanization process of step S2, the frequency of pressure cycle adjustment is controlled at 0.05-0.5 Hz, and the pressure fluctuation amplitude of each cycle does not exceed 30%.

4. A rubber roller high pressure vulcanization process according to claim 1, characterized in that: The instantaneous heating process in step S3 uses a high-frequency electromagnetic induction source, and the heating power is controlled at 5-50kW / m².

5. A rubber roller high pressure vulcanization process according to claim 1, characterized in that: During the intelligent temperature gradient control process of step S4, the external temperature decreases by 0.5-2°C per minute, and the internal temperature decreases by 1-3°C per minute to gradually balance the internal and external temperature differences.

6. A rubber roller high pressure vulcanization process according to claim 1, characterized in that: The metastable annealing process in step S5 is performed in an inert gas environment.

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