A method for determining the effective purity of rubber vulcanization accelerator

Abstract

The invention provides a method for determining the effective purity of a rubber vulcanization accelerator, relates to the technical field of rubber vulcanization, and comprises the following steps: step one: according to a standard vulcanization speed as a basis for division, multiple types of accelerators are selected as comparison objects, and 2-5 main components are selected as targets for each type of accelerator; step two: various raw materials are weighed according to a rubber compound formula, and a rubber compound is obtained after being fully mixed in a rubber mixing device, and the rubber compound is equidistantly divided into a plurality of rubber compound samples; the invention selects multiple types of accelerators as comparison objects, and multiple main components are selected as targets for each type of accelerator, and the rubber compound samples are respectively assisted in vulcanization by diluting them into N purity gears, and a change curve between purity and vulcanization completion time is determined, and a comparison model is constructed. When determining the accelerator to be measured, it is only necessary to perform auxiliary vulcanization on the rubber compound sample, obtain the vulcanization completion time, and compare it with the comparison model, so that the purity can be quickly determined, and the determination is more convenient.

Description

Technical Field

[0001] The invention relates to the technical field of rubber vulcanization, and in particular to a method for determining the effective purity of a rubber vulcanization accelerator. Background Art

[0002] Rubber accelerator refers to a rubber vulcanization accelerator. Rubber vulcanization is mainly carried out using sulfur, but the reaction between sulfur and rubber is very slow, so vulcanization accelerators came into being. Accelerators added to rubber can activate the vulcanizer, thereby accelerating the cross-linking reaction between the vulcanizer and rubber molecules, achieving the effect of shortening the vulcanization time and reducing the vulcanization temperature. The main vulcanization accelerators used are mainly sulfonamides, thiazoles, thiurams, and some guanidines, thioureas and dithiocarbamates according to their chemical structures. Among them, sulfonamides have the best comprehensive performance and are the most widely used.

[0003] In order to better utilize the rubber vulcanization accelerator and apply it in a variety of scenarios with different purity requirements, it is necessary to determine its purity range. In the prior art, chemical analysis is generally used to determine the purity of the vulcanization accelerator, which is relatively troublesome. Although the analysis is accurate, in ordinary use, it is only necessary to determine the approximate purity range of the vulcanization accelerator, and there is no need for overly precise measurement, which wastes a lot of time and affects efficiency. Therefore, the present invention proposes a method for determining the effective purity of a rubber vulcanization accelerator to solve the problems existing in the prior art. Summary of the invention

[0004] In view of the above problems, the present invention provides a method for determining the effective purity of a rubber vulcanization accelerator. The method for determining the effective purity of a rubber vulcanization accelerator can quickly determine the purity, and the determination is more convenient.

[0005] To achieve the purpose of the present invention, the present invention is implemented by the following technical scheme: a method for determining the effective purity of a rubber vulcanization accelerator, comprising the following steps:

[0006] Step 1: Based on the standard vulcanization speed, select multiple types of accelerators as comparison objects, and select 2-5 main components as targets for each type of accelerator;

[0007] Step 2: Weigh various raw materials according to the rubber compound formula, fully mix them in a rubber mixing device to obtain a rubber compound, and divide the rubber compound into multiple rubber compound samples at equal distances;

[0008] Step 3: Take each type of accelerator as a reaction set, use 2-5 specific components under this type to perform auxiliary vulcanization on the rubber sample separately, and observe the vulcanization completion time of the rubber sample;

[0009] Step 4: Repeat step 3 until all 2-5 specific components of all types of accelerators and their corresponding vulcanization times are tested and collected;

[0010] Step 5: dilute 2-5 specific components of each type of accelerator into N purity levels, and use the diluted products of each level to assist in vulcanization of the rubber sample;

[0011] Step 6: Plot a curve of the purity of 2-5 specific components in each type of accelerator and the change in vulcanization completion time, take the average value of the changes in different curves of 2-5 specific components as the standard curve of the purity of the accelerator and the change in vulcanization completion time, and construct a comparison model;

[0012] Step 7: Use the accelerator to be tested to perform auxiliary vulcanization on the rubber sample to obtain the vulcanization completion time of the rubber sample;

[0013] Step 8: Input the accelerator to be tested into the comparison model, identify the type of the accelerator to be tested, select the time variation standard curve of the corresponding type, and determine the purity according to the vulcanization completion time of the accelerator to be tested.

[0014] A further improvement is that in the step 1, the multiple types of accelerators are classified according to the standard vulcanization speed, including: super-speed grade: dithiocarbamates, xanthates; quasi-super-speed grade: thiuram; fast grade: thiazoles, xanthamides; medium-speed grade: guanidines; slow grade: aldehyde amines, thioureas.

[0015] A further improvement is that in the step 2, various raw materials are weighed according to the rubber formula, specifically including 50-120 parts of styrene-butadiene rubber, 2-6 parts of zinc stearate, 0.1-3 parts of sulfur, 5-80 parts of white carbon black and 0.5-1 part of zinc barium white, and the above raw materials are fully mixed in a rubber mixing equipment to obtain a rubber sample.

[0016] A further improvement is that in step 2, the rubber sample does not contain a vulcanization accelerator, and the thickness of the plurality of rubber samples is controlled to be 6 mm or less than 6 mm.

[0017] A further improvement is that in step three, multiple rubber samples are added to the mold respectively, and a vulcanizing agent is added, and then 2-5 specific components under each type of accelerator are used to assist in vulcanization of the rubber samples respectively, and the vulcanization temperature is controlled to be uniformly 150°C.

[0018] Further improvement is: in the step three, the vulcanization completion time of the rubber sample is observed, and the specific standard is: using a vulcanization analyzer to measure the property changes of the rubber sample, and checking whether the vulcanization mold can be easily opened, and there is no over-vulcanization phenomenon after opening the mold: stickiness, slag falling, and breakage, so as to determine that the vulcanization is completed.

[0019] A further improvement is that in step 5, the purity level is controlled until the difference between the vulcanization completion time of the rubber sample with the accelerator added and the vulcanization completion time without the accelerator added is less than 20 seconds.

[0020] A further improvement is that in step six, the comparison model is constructed specifically by constructing a plurality of main models based on the standard curves of the purity and vulcanization completion time of different types of accelerators. Under each main model, a sub-model is constructed based on the purity and vulcanization completion time variation curves of the corresponding 2-5 specific components. The vulcanization completion time is used as the trigger comparison target in the main model and the sub-model.

[0021] A further improvement is that in step seven, the rubber sample is subjected to auxiliary vulcanization using the accelerator to be tested for at least 2-3 cycles, and the average value of the vulcanization completion time is taken as a typical comparison value of the vulcanization completion time of the accelerator to be tested.

[0022] A further improvement is that in step eight, when it is necessary to further determine the purity, the Internet is connected to determine whether the accelerator to be tested is the same as or closest to a component among the 2-5 specific components under the corresponding type of accelerator, and the vulcanization completion time of the accelerator to be tested is compared again with the sub-model of the component to further determine its purity.

[0023] The beneficial effects of the present invention are:

[0024] 1. The present invention selects multiple types of accelerators as comparison objects, and each type of accelerator selects multiple main components as targets, which are diluted into N purity levels to perform auxiliary vulcanization on the rubber samples respectively, and the change curve between purity and vulcanization completion time is determined, and a comparison model is constructed. When measuring the accelerator to be tested, it is only necessary to perform auxiliary vulcanization on the rubber sample to obtain the vulcanization completion time, and compare it with the comparison model, so that the purity can be quickly determined, and the measurement is more convenient.

[0025] 2. The present invention constructs a comparison model. Once the model is constructed, it can provide a comparison standard for subsequent multiple measurements, greatly improving efficiency.

[0026] 3. The present invention constructs the standard curves of the purity and vulcanization completion time of different types of accelerators into multiple main models. Under each main model, a sub-model is constructed according to the purity and vulcanization completion time change curves of the corresponding multiple specific components. The vulcanization completion time of the accelerator to be tested is compared with the sub-model to facilitate further determination of its purity, thereby further improving the measurement accuracy while ensuring the measurement efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0028] In order to deepen the understanding of the present invention, the present invention will be further described in detail below in conjunction with examples. The examples are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0029] Embodiment 1

[0030] according to Figure 1 As shown, this embodiment proposes a method for determining the effective purity of a rubber vulcanization accelerator, comprising the following steps:

[0031] Step 1: Based on the standard vulcanization speed, select multiple types of accelerators as comparison objects, and select 2-5 main components as targets for each type of accelerator;

[0032] Step 2: Weigh various raw materials according to the rubber compound formula, fully mix them in a rubber mixing device to obtain a rubber compound, and divide the rubber compound into multiple rubber compound samples at equal distances;

[0033] Step 3: Take each type of accelerator as a reaction set, use 2-5 specific components under this type to perform auxiliary vulcanization on the rubber sample separately, and observe the vulcanization completion time of the rubber sample;

[0034] Step 4: Repeat step 3 until all 2-5 specific components of all types of accelerators and their corresponding vulcanization times are tested and collected;

[0035] Step 5: dilute 2-5 specific components of each type of accelerator into N purity levels, and use the diluted products of each level to assist in vulcanization of the rubber sample;

[0036] Step 6: Plot a curve of the purity of 2-5 specific components in each type of accelerator and the change in vulcanization completion time, take the average value of the changes in different curves of 2-5 specific components as the standard curve of the purity of the accelerator and the change in vulcanization completion time, and construct a comparison model;

[0037] Step 7: Use the accelerator to be tested to perform auxiliary vulcanization on the rubber sample to obtain the vulcanization completion time of the rubber sample;

[0038] Step 8: Input the accelerator to be tested into the comparison model, identify the type of the accelerator to be tested, select the time variation standard curve of the corresponding type, and determine the purity according to the vulcanization completion time of the accelerator to be tested.

[0039] The present invention selects multiple types of accelerators as comparison objects, and each type of accelerator selects multiple main components as targets, which are diluted into N purity levels to perform auxiliary vulcanization on rubber samples respectively, so as to determine the change curves of the purity of multiple specific components and the vulcanization completion time, and according to the average value of the change curve, the purity of each type of accelerator and the standard curve of the vulcanization completion time are determined, so as to construct a comparison model. When measuring the accelerator to be tested, it is only necessary to perform auxiliary vulcanization on the rubber sample to obtain the vulcanization completion time, and compare it with the corresponding type in the comparison model, so as to quickly determine the purity, and the measurement is more convenient. One-time model construction can provide a comparison standard for subsequent multiple measurements, which greatly improves the efficiency.

[0040] Embodiment 2

[0041] according to Figure 1 As shown, this embodiment proposes a method for determining the effective purity of a rubber vulcanization accelerator, comprising the following steps:

[0042] Based on the standard vulcanization speed, various types of accelerators are selected as comparison objects. For each type of accelerator, 2-5 main components are selected as targets. Various types of accelerators based on the standard vulcanization speed include: super-speed grade: dithiocarbamates, xanthates; quasi-super-speed grade: thiuram; fast grade: thiazole, hypoxanthine amide; medium-speed grade: guanidine; slow grade: aldehyde amine, thiourea; specifically covering all types of vulcanization accelerators, making the subsequent model comparison more extensive and suitable for the determination of various vulcanization accelerators;

[0043] Weigh various raw materials according to the rubber compound formula, specifically including: 100 parts of styrene-butadiene rubber, 5 parts of zinc stearate, 1 part of sulfur, 40 parts of white carbon black and 0.8 parts of zinc lithopone, and fully mix the above raw materials in a rubber mixing equipment to obtain a rubber compound sample, and divide the rubber compound into multiple rubber compound samples at equal intervals. The rubber compound samples do not contain a vulcanization accelerator, and the thickness of the multiple rubber compound samples is controlled to be 6 mm or less than 6 mm; the finished rubber compound samples have a thickness of less than 6 mm, and the rubber compound can be considered to be uniformly heated under the vulcanization process conditions, and its vulcanization time is the same as the positive vulcanization time;

[0044] Take each type of accelerator as a reaction set, add multiple rubber samples into the mold, add vulcanizer, and then use 2-5 specific components of each type of accelerator to perform auxiliary vulcanization on the rubber samples, control the vulcanization temperature to be uniformly 150°C, and observe the vulcanization completion time of the rubber samples. The specific standard is: use a vulcanization analyzer to measure the characteristic changes of the rubber samples. As the first judgment, check whether the vulcanization mold can be easily opened. After opening the mold, there is no over-vulcanization phenomenon: stickiness, slag, and breakage. As the second judgment, to determine that the vulcanization is completed, the judgment standard is more reliable; until all 2-5 specific components of all types of accelerators and the corresponding vulcanization time are fully tested and collected;

[0045] 2-5 specific components of each type of accelerator are diluted into N purity levels. The purity level is controlled until the difference between the vulcanization completion time of the rubber sample with the accelerator added and the vulcanization completion time without the accelerator added is less than 20S, and the rubber samples are assisted in vulcanization using the diluted products of each level. The difference between the vulcanization completion time of the rubber sample with the accelerator added and the vulcanization completion time without the accelerator added is less than 20S, which has the specific meaning of: representing that there is no obvious difference between the effect of the accelerator used at this time and the effect of not using the accelerator, and this is used as the minimum level for purity judgment; at the same time, the accelerator purity level when the vulcanization completion time is the fastest is used as the maximum level. In summary, the level control is more clearly subdivided, and the data obtained is more representative.

[0046] The purity of 2-5 specific components in each type of accelerator and the change of vulcanization completion time are plotted into a curve, and the average value of the changes in different curves of 2-5 specific components is taken as the standard curve of the purity and vulcanization completion time of the type of accelerator, so as to construct a comparison model, specifically: the standard curves of the purity and vulcanization completion time of different types of accelerators are constructed into multiple main models, and under each main model, a sub-model is constructed according to the purity and vulcanization completion time change curves of the corresponding 2-5 specific components, and the vulcanization completion time is used as the trigger comparison target in the main model and the sub-model; the main model uses the standard curves representing the purity and vulcanization completion time change of different types of accelerators, and the purity can be quickly compared and judged according to the type of the accelerator to be tested. The sub-model represents the purity and vulcanization completion time change curves of multiple specific components under the corresponding main model, which can determine whether the accelerator to be tested is the same as or closest to a component among the multiple specific components, and the sub-model of the component is used to compare the accelerator to be tested again to further determine its purity.

[0047] The accelerator to be tested is used to assist the vulcanization of the rubber sample for 3 cycles, and the average value of the vulcanization completion time is taken as the typical value for the comparison of the vulcanization completion time of the accelerator to be tested, so as to obtain the vulcanization completion time of the rubber sample; the accelerator to be tested is used to assist the vulcanization of the rubber sample for multiple cycles, so that the obtained vulcanization completion time comparison typical value is more accurate.

[0048] The accelerator to be tested is input into the comparison model, the type of accelerator to be tested is identified, the time variation standard curve of the corresponding type is selected, and the purity is determined according to the vulcanization completion time of the accelerator to be tested. When the purity needs to be further determined, the Internet is connected to determine whether the accelerator to be tested is the same as or closest to one of the 2-5 specific components under the corresponding type of accelerator, and the vulcanization completion time of the accelerator to be tested is compared again with the sub-model of the component to further determine its purity. While ensuring the measurement efficiency, the measurement accuracy is further improved.

[0049] The method for determining the effective purity of a rubber vulcanization accelerator selects multiple types of accelerators as comparison objects, and each type of accelerator selects multiple main components as targets, which are diluted into N purity levels to perform auxiliary vulcanization on rubber samples respectively, so as to determine the change curves of the purity of multiple specific components and the vulcanization completion time, and according to the average value of the change curve, the standard curve of the purity and vulcanization completion time of each type of accelerator is determined, so as to construct a comparison model. When determining the accelerator to be tested, it is only necessary to perform auxiliary vulcanization on the rubber sample to obtain the vulcanization completion time, and compare it with the corresponding type in the comparison model, so as to quickly determine the purity, and the measurement is more convenient. One-time model construction can provide a comparison standard for subsequent multiple measurements, thereby greatly improving efficiency. In addition, the present invention constructs the standard curves of the purity and vulcanization completion time of different types of accelerators into multiple main models. Under each main model, a sub-model is constructed according to the purity and vulcanization completion time change curves of the corresponding multiple specific components. During the measurement, the network is accessed to determine whether the accelerator to be measured is the same as or closest to a certain component among the multiple specific components under the corresponding type of accelerator. The vulcanization completion time of the accelerator to be measured is compared again with the sub-model of the component, so as to further determine its purity, and further improve the measurement accuracy while ensuring the measurement efficiency.

[0050] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for determining the effective purity of a rubber vulcanization accelerator, characterized in that: The following steps are involved: Step 1: Based on the standard vulcanization speed, select multiple types of accelerators as comparison objects, and select 2-5 main components as targets for each type of accelerator; Step 2: Weigh various raw materials according to the rubber compound formula, fully mix them in a rubber mixing device to obtain a rubber compound, and divide the rubber compound into multiple rubber compound samples at equal distances; Step 3: Take each type of accelerator as a reaction set, use 2-5 specific components under this type to perform auxiliary vulcanization on the rubber sample separately, and observe the vulcanization completion time of the rubber sample; Step 4: Repeat step 3 until all 2-5 specific components of all types of accelerators and their corresponding vulcanization times are tested and collected; Step 5: dilute 2-5 specific components of each type of accelerator into N purity levels, and use the diluted products of each level to assist in vulcanization of the rubber sample; Step 6: Plot a curve of the change of purity of 2-5 specific components in each type of accelerator and the vulcanization completion time, take the average value of the change of different curves of 2-5 specific components as the standard curve of the change of purity and vulcanization completion time of this type of accelerator, and construct a comparison model based on this. Specifically, construct the standard curve of the change of purity and vulcanization completion time of different types of accelerators into multiple main models, and under each main model, construct a sub-model according to the change curve of purity and vulcanization completion time of the corresponding 2-5 specific components, and use the vulcanization completion time as the trigger comparison target in the main model and the sub-model; Step 7: Use the accelerator to be tested to perform auxiliary vulcanization on the rubber sample to obtain the vulcanization completion time of the rubber sample; Step 8: Input the accelerator to be tested into the comparison model, identify the type of the accelerator to be tested, select the time variation standard curve of the corresponding type, and determine the purity according to the vulcanization completion time of the accelerator to be tested.

2. A method for determining the effective purity of a rubber vulcanization accelerator according to claim 1, characterized in that: In the step 1, the various types of accelerators are classified according to the standard vulcanization speed, including: super-speed grade: dithiocarbamates, xanthates; quasi-super-speed grade: thiuram; fast grade: thiazoles, hypoxanthines; medium-speed grade: guanidines; slow grade: aldehyde amines, thioureas.

3. A method for determining the effective purity of a rubber vulcanization accelerator according to claim 2, characterized in that: In the step 2, various raw materials are weighed according to the rubber compound formula, specifically including: 50-120 parts of styrene-butadiene rubber, 2-6 parts of zinc stearate, 0.1-3 parts of sulfur, 5-80 parts of white carbon black and 0.5-1 part of zinc lithopone, and the above raw materials are fully mixed in a rubber mixing equipment to obtain a rubber compound sample.

4. A method for determining the effective purity of a rubber vulcanization accelerator according to claim 3, characterized in that: In the step 2, the rubber sample does not contain a vulcanization accelerator, and the thickness of the plurality of rubber samples is controlled to be 6 mm or less than 6 mm.

5. A method for determining the effective purity of a rubber vulcanization accelerator according to claim 4, characterized in that: In the step three, a plurality of rubber samples are added into the mold respectively, and a vulcanizing agent is added, and then 2-5 specific components under each type of accelerator are used to perform auxiliary vulcanization on the rubber samples respectively, and the vulcanization temperature is controlled to be uniformly 150°C.

6. A method for determining the effective purity of a rubber vulcanization accelerator according to claim 5, characterized in that: In the step three, the vulcanization completion time of the rubber sample is observed. The specific standard is: using a vulcanization analyzer to measure the property changes of the rubber sample, and checking whether the vulcanization mold can be opened easily. After opening the mold, there is no over-vulcanization phenomenon: stickiness, slag falling, and breakage, so as to determine that the vulcanization is completed.

7. A method for determining the effective purity of a rubber vulcanization accelerator according to claim 6, characterized in that: In the step 5, the purity level is controlled until the difference between the vulcanization completion time of the rubber sample with the accelerator added and the vulcanization completion time without the accelerator added is less than 20 seconds.

8. A method for determining the effective purity of a rubber vulcanization accelerator according to claim 7, characterized in that: In the step 7, the rubber sample is subjected to auxiliary vulcanization using the accelerator to be tested for at least 2-3 cycles, and the average value of the vulcanization completion time is taken as the typical value for comparison of the vulcanization completion time of the accelerator to be tested.

9. A method for determining the effective purity of a rubber vulcanization accelerator according to claim 8, characterized in that: In step eight, when the purity needs to be further determined, the Internet is accessed to determine whether the accelerator to be tested is the same as or closest to a component among the 2-5 specific components under the corresponding type of accelerator, and the vulcanization completion time of the accelerator to be tested is compared again with the sub-model of the component to further determine its purity.

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