A method for predicting the glass transition temperature of a blend

Abstract

The application discloses a kind of methods for predicting glass transition temperature of rubber blend, belong to rubber technical field.Rubber blend is composed of styrene-butadiene rubber and cis-butadiene rubber, including determining the mixing degree MD of rubber blend step, calculating ΔTg step, and calculating the glass transition temperature Tg of rubber blend 并 Step.The application is applied to the prediction of glass transition temperature of rubber blend, solves the problem of large error when predicting the glass transition temperature of partially compatible or completely incompatible rubber blend system using FOX equation, can accurately and efficiently predict the glass transition temperature of rubber blend composition, has the characteristics of simple operation, effectively shortens product cycle, saves cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of rubber, and particularly relates to a method for predicting the glass transition temperature of a blend. BACKGROUND

[0002] The glass transition temperature is the temperature at which the molecular chain segment of an amorphous polymer (including the non-crystalline part in a crystalline polymer) begins to move under the action of external force, at which time the amorphous polymer changes from a glassy state to a high-elastic state. The glass transition temperature is a predetermined parameter of the performance index of a rubber composition, and is generally the lower limit of the use temperature of a rubber material, and is used to measure the cold resistance and molecular chain flexibility of the rubber, and has a great influence on the wear resistance and wet skid resistance of the tire tread rubber composition. The tread rubber composition with a low glass transition temperature has good wear resistance, and the tread rubber composition with a high glass transition temperature has a large hysteresis loss (tan δ @ 0℃) at about 0℃, and has good wet skid resistance. According to the different seasons and regions, it is necessary to develop rubber compositions with different glass transition temperatures. With the improvement of people's energy-saving and environmental protection consciousness, green tires have developed rapidly, and the use of white carbon black as a filling system reduces the rolling resistance and improves the wet grip performance. The affinity of styrene-butadiene rubber and white carbon black is good, and the microstructure and sequence structure can be adjusted, and the styrene-butadiene rubber has become the first choice for the tread rubber. However, the wear resistance of the rubber filled with white carbon black is slightly poor, and a small amount of butadiene rubber is usually used to improve the wear resistance. At present, the tread rubber for tires mainly uses a styrene-butadiene rubber / butadiene rubber blend system. Therefore, it is very important to predict the glass transition temperature of the styrene-butadiene rubber / butadiene rubber blend.

[0003] The paper "Prediction of Rubber Glass Transition Temperature Based on Gaussian Process Regression" (Chen Zhudan, Li Dazi, Liu Jun, et al. Prediction of Rubber Glass Transition Temperature Based on Gaussian Process Regression [J]. Rubber Industry, 2022, 69(11): 826-829.) discloses the use of a Gaussian process regression model to predict the glass transition temperature of styrene-based and vinyl-based solution styrene-butadiene rubber within a certain range. However, this model is suitable for predicting the glass transition temperature of a single rubber formula system, but not for a rubber blend system. Generally, to achieve excellent performance, rubber compositions rarely use a single rubber, but rather use a multi-component blend, which limits the practical application of this model. The commonly used method to predict the glass transition temperature of multi-component copolymers is the FOX equation (1 / Tg = W1 / Tg1 + W2 / Tg2 +... + Wn / Tgn), where Tg represents the glass transition temperature of the copolymer, W1, W2... Wn represent the mass fraction of each monomer in the copolymer, and Tg1, Tg2... Tgn represent the glass transition temperature of each monomer in the copolymer. However, this method is only suitable for estimating the glass transition temperature of completely compatible blend systems. For partially compatible and completely incompatible blend systems, the estimated glass transition temperature differs greatly from the actual test, especially for poorly compatible blend systems, with a difference of tens of degrees. This large error limits the use of the FOX equation in the design and development process of rubber compositions.

[0004] To obtain accurate glass transition temperatures, the design and development of rubber compositions can only be done by mixing and testing all schemes one by one in the traditional way, which is time-consuming and seriously affects the development efficiency, resulting in a huge waste of labor, materials, and testing costs. The traditional method of designing and developing rubber compositions involves testing and verifying multiple schemes according to the development goals. Since the glass transition temperature of rubber compositions determines the safety and wear, grip, and other key properties of tires under extreme conditions, it is the first consideration. The specific implementation method is as follows: different rubbers and ratios are selected for testing and verification based on the target glass transition temperature. Since there is no accurate and effective method to predict the glass transition temperature, a large number of test schemes are required. All schemes are mixed in an internal mixer, sheeted on an open mill, sampled, vulcanized using a flat vulcanizing machine, cut with a cutter, and all samples are scanned for temperature on a dynamic mechanical analyzer to obtain the glass transition temperature of the rubber composition. The schemes that do not meet the target glass transition temperature are discarded, and the schemes that meet the target are optimized for other performance verification. If no suitable scheme is optimized, all schemes are discarded for the next round of scheme design and verification until a suitable scheme is optimized. This method requires a large amount of manpower, material resources, and financial resources to implement. SUMMARY

[0005] In view of the deficiencies of the prior art, the technical problem to be solved by the present application is to solve the problem of large error in predicting the glass transition temperature of a rubber blending system that is partially compatible or completely incompatible using the FOX equation, and to provide a method for predicting the glass transition temperature of a rubber blend that is accurate and efficient.

[0006] To solve the technical problem, the technical scheme adopted by the present application is:

[0007] The present application provides a method for predicting the glass transition temperature of a rubber blend, the rubber blend being composed of styrene-butadiene rubber and butadiene rubber, the mass fraction of the styrene-butadiene rubber in the rubber blend being not less than 50%, and the method comprising:

[0008] The step of determining the mixing degree MD of the rubber blend comprises calculating the mixing degree MD of the rubber blend by the following formula:

[0009] MD = 1 - 0.67 x | (2.72 x St S - 0.69 (Vi S - Vi B ) |

[0010] St S is the mass percentage of styrene groups in the molecular chain of the styrene-butadiene rubber, Vi S is the mass percentage of vinyl groups in the molecular chain of the styrene-butadiene rubber, and Vi B is the mass percentage of vinyl groups in the molecular chain of the butadiene rubber.

[0011] The step of calculating ΔTg comprises

[0012] calculating the influence of the butadiene rubber on the glass transition temperature of the rubber blend ΔTg:

[0013] ΔTg = W B x (Tg S - Tg B ) x MD

[0014] W B is the mass percentage of the butadiene rubber in the rubber blend, Tg S is the glass transition temperature of the styrene-butadiene rubber, and Tg B is the glass transition temperature of the butadiene rubber.

[0015] The step of calculating the glass transition temperature Tg 并 of the rubber blend comprises:

[0016] Tg 并 = Tg S - ΔTg.

[0017] Preferably, before the step of determining the mixing degree MD of the blend rubber, there is further comprising:

[0018] a step of determining the glass transition temperature Tg of the styrene-butadiene rubber by DMA test S and the glass transition temperature Tg of the cis-butadiene rubber B , comprising

[0019] placing the single rubber formula vulcanized rubber of the styrene-butadiene rubber into a dynamic mechanical analyzer to record the loss tangent value at different temperatures, and the temperature corresponding to the loss tangent peak is recorded as the glass transition temperature Tg of the styrene-butadiene rubber S ; and

[0020] placing the single rubber formula vulcanized rubber of the cis-butadiene rubber into a dynamic mechanical analyzer to record the loss tangent value at different temperatures, and the temperature corresponding to the loss tangent peak is recorded as the glass transition temperature Tg of the cis-butadiene rubber B .

[0021] Preferably, before the step of determining the mixing degree MD of the blend rubber, there is further comprising:

[0022] characterizing the styrene group and vinyl group content in the molecular chain of the styrene-butadiene rubber and the cis-butadiene rubber by nuclear magnetic resonance instrument, and obtaining the mass percentage of the styrene group in the molecular chain of the styrene-butadiene rubber as St S , the mass percentage of the vinyl group in the molecular chain of the styrene-butadiene rubber as Vi S , and the mass percentage of the vinyl group in the molecular chain of the cis-butadiene rubber as Vi B .

[0023] Preferably, the DMA test adopts a tensile mode, the frequency is 1-10 Hz, the static strain is 1%-7%, the dynamic strain is 0.1%-0.25%, the temperature scanning range is -90°C-80°C, and the heating rate is 1-10°C / min.

[0024] Preferably, the frequency is 10 Hz, the static strain is 7%, the dynamic strain is 0.25%, the temperature scanning range is -90°C-80°C, and the heating rate is 2-3°C / min.

[0025] Preferably, the test sample of the DMA test is a rectangular test sample, the clamping distance is 10-30 mm, the width is 4-8 mm, and the thickness is 1-3 mm.

[0026] Preferably, the clamping distance is 30 mm, the width is 6 mm, and the thickness is 2 mm.

[0027] Preferably, the styrene-butadiene rubber is a solution polymerized styrene-butadiene rubber or an emulsion polymerized styrene-butadiene rubber, the mass percentage of styrene groups in the molecular chain of the styrene-butadiene rubber is 10%-45%, and the mass percentage of vinyl groups is 10%-55%.

[0028] Preferably, the butadiene rubber is any one of a neodymium-based butadiene rubber, a nickel-based butadiene rubber, a titanium-based butadiene rubber or a cobalt-based butadiene rubber.

[0029] Preferably, the mass percentage of vinyl groups in the molecular chain of the butadiene rubber is 0-15%.

[0030] Compared with the prior art, the present application has the following beneficial effects:

[0031] The present application provides a method for predicting the glass transition temperature of a blend rubber composed of a styrene-butadiene rubber and a butadiene rubber, which is simple to operate, can quickly and accurately predict the glass transition temperature of the blend rubber, and the absolute error between the predicted value and the measured value is controlled within 3 DEG C, thereby shortening the development cycle of the composition, reducing the workload and saving costs. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 A comparison chart of the results of the glass transition temperature of the blend rubber calculated by the prediction method provided by the present application and the FOX equation;

[0033] Figure 2 A chart of the glass transition temperature of the single rubber and the blend rubber provided by the present application. DETAILED DESCRIPTION

[0034] The technical solutions in the specific embodiments of the present application will be described in detail and completely below with reference to the drawings. Obviously, the described embodiments are only part of the specific embodiments of the general technical solution of the present application, but not all the embodiments. Based on the general concept of the present application, all other embodiments obtained by those skilled in the art fall within the scope of protection of the present application.

[0035] The present application provides a method for predicting the glass transition temperature of a blend rubber composed of a styrene-butadiene rubber and a butadiene rubber, the mass fraction of the styrene-butadiene rubber in the blend rubber is not less than 50%, and the method comprises the following steps:

[0036] The step of determining the mixing degree MD of the blend rubber comprises calculating the mixing degree MD of the blend rubber by the following formula:

[0037] MD = 1 - 0.67 x | (2.72 x St S - 0.69 (Vi S - Vi B ) |

[0038] St Sthe mass percentage of styrene groups in the molecular chain of the butadiene rubber, the Vi S the mass percentage of vinyl groups in the molecular chain of the butadiene rubber, the Vi B the mass percentage of vinyl groups in the molecular chain of the butadiene rubber, the Vi

[0039] calculating the effect of the butadiene rubber on the glass transition temperature of the blend ΔTg:

[0040] calculating the effect of the butadiene rubber on the glass transition temperature of the blend ΔTg:

[0041] ΔTg = W B x (Tg S - Tg B ) x MD

[0042] W B is the mass percentage of the butadiene rubber in the blend, Tg S is the glass transition temperature of the butadiene rubber, Tg B is the glass transition temperature of the butadiene rubber, Tg

[0043] calculating the glass transition temperature Tg 并 of the blend, the step comprising:

[0044] Tg 并 = Tg S - ΔTg.

[0045] The butadiene styrene rubber / butadiene rubber blending system is the main choice of tire tread rubber, however, due to the difference of butadiene styrene rubber and / or butadiene rubber, and with the change of the mass percentage of butadiene styrene rubber and butadiene rubber in the blending system, the butadiene styrene rubber and butadiene rubber in the blending system may be partially compatible or even incompatible, and the FOX equation has a large error in predicting the glass transition temperature of the partially compatible rubber composition (the absolute error is 3-21℃), therefore, it is difficult to predict the glass transition temperature of the partially compatible system at present, a large number of experiments are needed to adjust to the appropriate glass transition temperature to meet the product requirements of different regions and seasons, the development cycle is long, and a large amount of manpower, material resources and financial resources are consumed. The above-mentioned blending rubber glass transition temperature prediction method provided by the present application only needs to perform dynamic mechanical testing and rubber microstructure characterization on the single rubber vulcanized rubber to accurately and efficiently predict the glass transition temperature of the partially compatible SBR (butadiene styrene rubber) / BR (butadiene rubber) blending rubber, which is simple to operate, high in accuracy, can be used to design rubber compositions for different regions and seasons, shorten the product development time, save costs, and the absolute error between the predicted value and the measured value of the glass transition temperature of the rubber composition under the above-mentioned experimental conditions can be controlled within 3℃, and the comparison chart of the glass transition temperatures of the blending rubber calculated by the prediction method and the FOX equation is shown in Figure 1 The test results of the glass transition temperatures of the single rubber and the blending rubber are shown in Figure 2 The prediction method provided by the present application calculates the mixing degree of the SBR / BR blending system according to the difference between the molecular structures of BR and SBR, and then predicts the glass transition temperature of the partially compatible SBR / BR blending rubber. Specifically, when the SBR and BR are partially compatible, the SBR-rich phase and BR-rich phase exist due to the failure to reach the molecular level mixing degree, when the glass transition temperature of the SBR-rich phase is the main peak of the SBR / BR blending rubber (i.e. the mass fraction of butadiene styrene rubber in the blending rubber is not less than 50%), according to the mixing degree of BR and SBR, the influence of BR on the glass transition temperature of the SBR-rich phase ΔTg can be calculated, and then the glass transition temperature of the partially compatible SBR / BR blending rubber can be predicted.

[0046] In a preferred embodiment, before the step of determining the mixing degree MD of the blending rubber, the step of determining the glass transition temperature Tg S of the butadiene styrene rubber and the glass transition temperature Tg B of the butadiene rubber by DMA test is further included, which comprises

[0047] The single rubber formula vulcanized rubber of the butadiene styrene rubber is placed in a dynamic mechanical analyzer to record the loss tangent value at different temperatures, and the temperature corresponding to the peak value of the loss tangent is recorded as the glass transition temperature Tg S; and

[0048] putting the butadiene rubber single-species formulation vulcanizate into a dynamic mechanical analyzer to record the loss tangent value at different temperatures, and taking the temperature corresponding to the peak value of the loss tangent as the glass transition temperature Tg of the butadiene rubber B .

[0049] Regarding the above DMA test, specifically including: designing butadiene rubber, butadiene rubber single-species formulation, two-stage mixing on a mixer, sheet cooling under a roll mill, hot pressing vulcanization on a flat vulcanizing machine, butadiene rubber, butadiene rubber single-species formulation vulcanizate on DMA to obtain the glass transition temperature of the single-species formulation vulcanizate.

[0050] In a preferred embodiment, before the step of determining the mixing degree MD of the blend, further comprising: using a nuclear magnetic resonance instrument to characterize the styrene group and vinyl group content in the molecular chain of the butadiene rubber and the butadiene rubber, and obtaining the mass percentage of the styrene group in the molecular chain of the butadiene rubber as St S , the mass percentage of the vinyl group in the molecular chain of the butadiene rubber as Vi S , and the mass percentage of the vinyl group in the molecular chain of the butadiene rubber as Vi B .

[0051] In a preferred embodiment, the DMA test uses a tensile mode, a frequency of 1-10 Hz, a static strain of 1%-7%, a dynamic strain of 0.1%-0.25%, a temperature scanning range of -90°C-80°C, and a heating rate of 1-10°C / min. This embodiment specifically limits the frequency, static strain, dynamic strain, temperature scanning range, and heating rate of the DMA test. It can be understood that the frequency can also be 2 Hz, 3 Hz, 4 Hz, 5 Hz, 6 Hz, 7 Hz, 8 Hz, 9 Hz, and any point value within the range thereof, the static strain can also be 2%, 3%, 4%, 5%, 6%, and any point value within the range thereof, the dynamic strain can also be 0.15%, 0.20%, and any point value within the range thereof, and the heating rate can also be 2°C / min, 3°C / min, 4°C / min, 5°C / min, 6°C / min, 7°C / min, 8°C / min, 9°C / min, and any point value within the range thereof. In a preferred embodiment, the frequency is 10 Hz, the static strain is 7%, the dynamic strain is 0.25%, the temperature scanning range is -90°C-80°C, and the heating rate is 2-3°C / min.

[0052] In a preferred embodiment, the test sample of the DMA test is a rectangular test piece with a clamp distance of 10-30 mm, a width of 4-8 mm, and a thickness of 1-3 mm. This embodiment specifically defines the clamp distance, the width, and the thickness. It can be understood that the clamp distance can also be 15 mm, 20 mm, 25 mm, and any point value within the range thereof, the width (the width of the rectangular test piece) can also be 5 mm, 6 mm, 7 mm, and any point value within the range thereof, and the thickness (the thickness of the rectangular test piece) can also be 2 mm. In a preferred embodiment, the clamp distance is 30 mm, the width is 6 mm, and the thickness is 2 mm.

[0053] In a preferred embodiment, the styrene-butadiene rubber is a solution-polymerized styrene-butadiene rubber or an emulsion-polymerized styrene-butadiene rubber, the mass percentage of styrene groups in the molecular chain of the styrene-butadiene rubber is 10%-45%, and the mass percentage of vinyl groups in the molecular chain of the styrene-butadiene rubber is 10%-55%; the butadiene rubber is any one of a neodymium-based butadiene rubber, a nickel-based butadiene rubber, a titanium-based butadiene rubber, or a cobalt-based butadiene rubber, and the mass percentage of vinyl groups in the molecular chain of the butadiene rubber is 0-15%.

[0054] In a preferred embodiment, the mass percentage of vinyl groups in the molecular chain of the butadiene rubber is 0-15%.

[0055] In order to more clearly and specifically introduce the method for predicting the glass transition temperature of the rubber blend provided by the embodiments of the present application, the following will be described in combination with specific embodiments.

[0056] Embodiments

[0057] In order to verify the accuracy of the prediction formula of the present application, different SBR / BR blend system rubber compositions were prepared by changing the grade and blend ratio of SBR, and the predicted value, the calculated value by the FOX formula, and the actual glass transition temperature tested by the dynamic mechanical analyzer were compared. The specific steps are as follows:

[0058] The test formula was designed, and the rubber compound was mixed and vulcanized according to the following steps:

[0059] 1) Put the raw rubber, zinc oxide, stearic acid, 6PPD, wax, white carbon black, and silane coupling agent into the internal mixer, and press the plug to mix for 40 s or to 115°C, with the internal mixer rotating at 90 rpm;

[0060] 2) After the plug is lifted and cleaned, press the plug to mix for 40 s or to 135°C, with the internal mixer rotating at 90 rpm;

[0061] 3) After the plug is lifted, press the plug to mix for 30 s or to 145°C, with the internal mixer rotating at 90 rpm;

[0062] 4) After the plug is lifted, press the plug to mix at 145°C for 180 s;

[0063] 5) Cooling the discharged sheet to obtain the masterbatch;

[0064] 6) After the discharge, the sheet is mixed with vulcanizing agent and accelerator at 60 rpm for 30 s or until 85°C.

[0065] 7) After the discharge, the sheet is mixed at 60 rpm until 100°C.

[0066] 8) After the discharge, the sheet is mixed at 60 rpm for 30 s or until 110°C.

[0067] 9) Cooling the discharged sheet to obtain the final batch.

[0068] 10) Vulcanization at 161°C for 20 min under 12 MPa pressure on a flat vulcanization machine.

[0069] The glass transition temperature of BR and SBR single rubber system vulcanized rubber is tested by dynamic mechanical analyzer, and the test conditions are as follows: frequency 10 Hz, static strain 7%, dynamic strain 0.25%, temperature scanning range-90°C-80°C, and heating rate 3°C / min.

[0070] The microstructure of the rubber composition is analyzed by using nuclear magnetic resonance instrument, and the information of the rubber composition formula, microstructure and glass transition temperature of BR and SBR single rubber system is shown in Table 1.

[0071] Table 1 Information of rubber composition formula, microstructure and glass transition temperature of BR and SBR single rubber system

[0072]

[0073] The SBR / BR blend system test formula is designed, the grade of SBR and the blend ratio are changed, and the other formula components are the same as the above single rubber test formula, and the preparation method is the same as the single rubber preparation method.

[0074] According to the DMA and nuclear magnetic resonance test results and the blend ratio of BR, the glass transition temperature of partially compatible SBR / BR blend rubber is predicted, and the glass transition temperature of the blend rubber is calculated according to the FOX formula.

[0075] The glass transition temperature of partially compatible SBR / BR blend system is obtained by dynamic mechanical analyzer test. The DMA test conditions are the same as the single rubber vulcanized rubber test conditions.

[0076] The information of the rubber composition formula, microstructure and glass transition temperature of SBR / BR blend rubber system is shown in Table 2.

[0077] Table 2 Information of rubber composition formula, microstructure and glass transition temperature of SBR / BR blend rubber system

[0078]

[0079]

[0080] Note: Other components in the formula are the same as those in Table 1 single rubber species system rubber composition formula.

[0081] From the data in the above table, it can be found that the glass transition temperature of the rubber composition predicted by the method in the application is close to the measured glass transition temperature, the absolute error is within 3°C, most of the schemes are within 2°C, and the glass transition temperature predicted by using the FOX equation has a large difference from the measured value, and the difference can be more than 20°C.

Claims

1. A method for predicting the glass transition temperature of a blend of a butadiene-styrene rubber and a butadiene rubber, the mass fraction of the butadiene-styrene rubber in the blend being not less than 50%, characterized in that, The method comprises the following steps: The step of determining the mixing degree MD of the blend rubber comprises calculating the mixing degree MD of the blend rubber by the following formula: MD = 1 - 0.67 x | (2.72 x St S - 0.69 (Vi S - Vi B )) | The St S is the mass percentage of styrene groups in the molecular chain of the butadiene rubber, the Vi S is the mass percentage of vinyl groups in the molecular chain of the butadiene rubber, the Vi B is the mass percentage of vinyl groups in the molecular chain of the butadiene rubber, the Vi The step of calculating ΔTg comprises The step of calculating the influence of the butadiene rubber on the glass transition temperature of the blend rubber ΔTg comprises ATg = W B x (Tg S -Tg B ) x MD W B is the mass percentage of the cis-butadiene rubber in the blend, Tg S is the glass transition temperature of the butadiene-styrene rubber, Tg B is the glass transition temperature of the cis-butadiene rubber; calculating the glass transition temperature Tg of the blend 并 comprising: Tg 并 = Tg S - ΔTg.

2. The parallel rubber glass transition temperature prediction method according to claim 1, characterized in that, Before the step of determining the mixing degree MD of the blend rubber, the method further comprises the following steps: determining the glass transition temperature Tg of the butadiene rubber by means of DMA S and the glass transition temperature Tg of the cis-butadiene rubber B comprises The single rubber species formulation of the styrene butadiene rubber vulcanizate is placed into a dynamic mechanical analyzer to record the loss tangent value at different temperatures, and the temperature corresponding to the peak value of the loss tangent is recorded as the glass transition temperature Tg of the styrene butadiene rubber S ; and The single rubber species formulation vulcanized rubber of the butadiene rubber is put into a dynamic mechanical analyzer to record the loss tangent value at different temperatures, and the temperature corresponding to the peak value of the loss tangent is recorded as the glass transition temperature Tg of the butadiene rubber B .

3. The method of predicting the glass transition temperature of a hybrid adhesive according to claim 1, wherein, Before the step of determining the mixing degree MD of the blend rubber, the method further comprises the following steps: The styrene group and vinyl group content in the molecular chain of the butadiene rubber and the cis-butadiene rubber are characterized by using a nuclear magnetic resonance instrument, and the mass percentage of the styrene group in the molecular chain of the butadiene rubber is St S , the mass percentage of the vinyl group in the molecular chain of the butadiene rubber is Vi S , and the mass percentage of the vinyl group in the molecular chain of the cis-butadiene rubber is Vi B .

4. The parallel rubber glass transition temperature prediction method according to claim 2, wherein, The DMA test adopts a tensile mode, a frequency of 1-10 Hz, a static strain of 1%-7%, a dynamic strain of 0.1%-0.25%, a temperature scanning range of-90℃-80℃, and a heating rate of 1-10℃ / min.

5. The parallel rubber glass transition temperature prediction method according to claim 4, characterized in that, The frequency is 10 Hz, the static strain is 7%, the dynamic strain is 0.25%, the temperature scanning range is-90℃-80℃, and the heating rate is 2-3℃ / min.

6. The parallel rubber glass transition temperature prediction method according to claim 2, wherein, The test sample of the DMA test is a rectangular test piece with a clamping distance of 10-30 mm, a width of 4-8 mm, and a thickness of 1-3 mm.

7. The parallel rubber glass transition temperature prediction method according to claim 6, wherein, The clamping distance is 30 mm, the width is 6 mm, and the thickness is 2 mm.

8. The method of predicting the glass transition temperature of a hybrid adhesive according to claim 1, wherein, The styrene-butadiene rubber is a solution-polymerized styrene-butadiene rubber or an emulsion-polymerized styrene-butadiene rubber, the mass percentage of styrene groups in the molecular chain of the styrene-butadiene rubber is 10%-45%, and the mass percentage of vinyl groups is 10%-55%.

9. The method of predicting the glass transition temperature of a hybrid adhesive according to claim 1, wherein, The butadiene rubber is any one of a neodymium-based butadiene rubber, a nickel-based butadiene rubber, a titanium-based butadiene rubber, or a cobalt-based butadiene rubber.

10. The method of predicting the glass transition temperature of a hybrid adhesive according to claim 9, wherein, The mass percentage of vinyl groups in the molecular chain of the butadiene rubber is 0-15%.

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