Method for determining formaldehyde release rate in material based on rapid thermal analysis method

Abstract

The invention provides a method for determining the formaldehyde release rate in a material based on a rapid thermal analysis method, which comprises the following steps: S1, pretreating a to-be-determined material, and dividing the to-be-determined material into a plurality of test groups; s2, testing the test group in the step S1 through operation of the comprehensive thermal analyzer, and drawing a heat flow curve of the comprehensive thermal analyzer; and S3, obtaining the release rate of the formaldehyde according to the heat flow curve. The method has the beneficial effects that the comprehensive thermal analyzer is adopted for determination, the material can be rapidly heated, the time consumed by material determination is shortened, and after nitrogen is injected into the determination environment, nitrogen can protect formaldehyde from being oxidized by oxygen in air, so that the determination error is reduced, and the determination accuracy is improved, which shows that the method has good application prospects. The method for determining the formaldehyde release rate in the material based on the rapid thermal analysis method provided by the invention has relatively high efficiency and stability, and is more suitable for promotion.

Description

Technical Field

[0001] The invention belongs to the technical field of material determination, and in particular relates to a method for determining the formaldehyde release rate in a material based on a rapid thermal analysis method. Background Art

[0002] Determining the formaldehyde release rate in materials is of great significance for protecting human health and environmental safety. By understanding the release performance of materials, more environmentally friendly and healthy materials can be selected for use in construction, furniture, decoration and other fields, thereby reducing formaldehyde pollution to indoor air quality.

[0003] In the prior art, the traditional detection method usually adopts the method of static measurement at room temperature. During the measurement process, the material will be affected by the change of environmental conditions, resulting in changes in the release environment of the material, which will affect the accuracy of the test results. Summary of the invention

[0004] In view of this, the present invention aims to propose a method for determining the formaldehyde release rate in a material based on rapid thermal analysis to solve at least one technical problem in the background technology.

[0005] To achieve the above object, the technical solution of the present invention is achieved as follows: A method for determining the formaldehyde release rate in a material based on rapid thermal analysis comprises the following steps: S1: pre-treat the materials to be measured and divide the materials to be measured into several test groups; S2: The test group in step S1 is run through a comprehensive thermal analyzer to start measurement, and a heat flow curve of the comprehensive thermal analyzer is drawn; S3: How to obtain the formaldehyde release rate based on the heat flow curve and how to calculate it.

[0006] Furthermore, the pretreatment in step S1 is any one of punching, rolling and crushing, and the materials after the pretreatment are ready for grouping.

[0007] Furthermore, in step S2, the materials of the test group obtained in step S1 are weighed to ensure that the weight is consistent, and then one material is taken out and placed in a crucible, and the crucible containing the material is sent into the comprehensive thermal analyzer. After ensuring that it is placed stably, the comprehensive thermal analyzer is sealed and waited for measurement.

[0008] Furthermore, the initial temperature of the comprehensive thermal analyzer in step S2 is set to 20-40°C, and after the comprehensive thermal analyzer is started, it is set to heat up to 300°C at a heating rate of 20-30°C / min.

[0009] Furthermore, in step S2, during the temperature rising stage, the comprehensive thermal analyzer is operated to inject gas into the chamber, and the gas is any one of air, oxygen and nitrogen.

[0010] Furthermore, the gas injection time is 1-3 minutes from the start of heating.

[0011] Furthermore, it also includes entering the data of the heat flow curve into the analysis software, smoothing and filtering the initial data, analyzing and calculating the heat flow curve, Extract the key data from the heat flow curve, extract the key data, and obtain the analysis data of the comprehensive thermal analyzer based on the analysis results and data extraction records.

[0012] The key data in the heat flow curve include baseline step, exothermic peak and endothermic peak, peak area, heating rate and sample amount. The volatilization rate of formaldehyde is closely related to temperature. The heat flow curve can show the heat change of the sample during the heating process, and then obtain the release of formaldehyde at different temperatures. According to the area of ​​the exothermic peak, the formaldehyde release amount can be calculated.

[0013] Compared with the prior art, the method for determining the formaldehyde release rate in a material based on rapid thermal analysis according to the present invention has the following advantages: In the present invention, the measurement results are relatively close to the data measured by the traditional measurement method, and the difference in the results obtained by multiple measurements is small, indicating that the measurement results are relatively stable. At the same time, the comprehensive thermal analyzer is used for measurement, which can quickly heat the material and reduce the time consumed in material measurement. After nitrogen is injected into the measurement environment, the nitrogen can protect formaldehyde from being oxidized by oxygen in the air, thereby reducing measurement errors and improving measurement accuracy. This shows that the method for measuring the formaldehyde release rate in a material based on rapid thermal analysis provided by the present invention has high efficiency and stability and is more suitable for promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings constituting part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0015] Figure 1 This is a flow chart of the method for determining the formaldehyde release rate in a material described in Example 1 of the present invention. DETAILED DESCRIPTION

[0016] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0017] The present invention will be described in detail below with reference to examples.

[0018] Example 1 A method for determining the formaldehyde release rate in a material based on rapid thermal analysis comprises the following steps: S1: Obtain the material to be measured, which is a whole plate, cut the plate into multiple materials to be measured with uniform size, divide the materials to be measured into two groups, and perform conventional measurement method and rapid measurement method on the two groups of materials to be measured respectively; S2: Materials requiring conventional determination methods shall be uniformly tested for formaldehyde release rate using conventional determination methods.

[0019] S3: After the comprehensive thermal analyzer is running, the material is measured; S4: Input and analyze the data of the measurement results of the conventional measurement method and the rapid measurement method to obtain the difference in the results between the conventional measurement method and the rapid measurement method.

[0020] The steps of the conventional determination method of step S2 are: Toluene is used as a solvent to soak the material, and the formaldehyde in the material is extracted by the solvent; After the formaldehyde extraction is completed, a color developer is added to the solvent to allow the formaldehyde to react with the color developer to generate a colored compound; Measure 2.8 ml of the above solution, dilute with water, then place in a volumetric flask, add 20 times sodium hydroxide solution and let stand for 15 minutes, then measure the same amount of iodine solution and dilute with water; Based on the above preparation, 25 ml of potassium iodate standard solution was measured, 75 ml of hot water was added, 3 g of potassium iodide and 10 ml of glacial acetic acid solution were added, and after shaking, 1 ml of starch solution was added, and then the volume of the solution was recorded. Finally, the formaldehyde content was calculated, and the calculation formula was: Wherein, W is the formaldehyde determination result, V is the volume of the sample absorption liquid, H is the water content of the sample, m is the mass of the sample, and F is the calculation parameter of the result; By performing the same measurement steps on multiple materials, the measurement results of the conventional measurement method are obtained.

[0021] After completing multiple measurements using the conventional measurement method in step S2, the measurement results of each measurement are recorded, stored, and wait for comparison.

[0022] Example 2 The rapid determination method uses different conditions to conduct comparative determinations on the materials. The steps of the rapid determination method are: Divide multiple materials into multiple groups, use different processing and measurement methods for each group of materials, and after completing the measurement operation, obtain multiple groups of multiple comparison measurement data; The material is pre-processed by punching holes, and the pre-processed material is ready for measurement. Weigh multiple batches of materials for comparative measurement to ensure that the weights are consistent, then take a material and place it in a crucible, send the crucible containing the material into the comprehensive thermal analyzer, ensure that it is placed stably, and then seal the comprehensive thermal analyzer and wait for measurement; The initial temperature of the comprehensive thermal analyzer was set to 30°C, and after the comprehensive thermal analyzer was started, it was set to increase the temperature to 300°C at a heating rate of 25°C / min; During the heating stage, operate the comprehensive thermal analyzer to inject gas, and the gas is air; The gas injection time was 2 min from the start of the temperature rise, and the gas injection time was 2 min; S4: After the material is tested by the comprehensive thermal analyzer, the heat flow curve of the comprehensive thermal analyzer is observed, the data of the heat flow curve is input into the analysis software, the initial data is smoothed and filtered for preprocessing, the heat flow curve is analyzed and calculated, the key data in the heat flow curve is extracted, the key data is extracted, and the analysis data of the comprehensive thermal analyzer is obtained according to the analysis results and data extraction records; S5: Input and analyze the data of the measurement results of the conventional measurement method and the rapid measurement method to obtain the difference in the results between the conventional measurement method and the rapid measurement method.

[0023] Example 3 The difference between this embodiment and embodiment 2 is only that: The rapid determination method uses different conditions to conduct comparative determinations on the materials. The steps of the rapid determination method are: Divide multiple materials into multiple groups, use different processing and measurement methods for each group of materials, and after completing the measurement operation, obtain multiple groups of multiple comparison measurement data; Pre-treat the material by rolling it, and the pre-treated material is ready for measurement; Weigh multiple batches of materials for comparative measurement to ensure that the weights are consistent, then take a material and place it in a crucible, send the crucible containing the material into the comprehensive thermal analyzer, ensure that it is placed stably, and then seal the comprehensive thermal analyzer and wait for measurement; The initial temperature of the comprehensive thermal analyzer was set to 30°C, and after the comprehensive thermal analyzer was started, it was set to increase the temperature to 300°C at a heating rate of 25°C / min; During the heating stage, operate the comprehensive thermal analyzer to inject gas, and the gas is oxygen; The gas injection time is 2 min from the start of heating, and the gas injection time is 2 min.

[0024] Example 4 The difference between this embodiment and embodiment 2 is only that: The rapid determination method uses different conditions to conduct comparative determinations on the materials. The steps of the rapid determination method are: Divide multiple materials into multiple groups, use different processing and measurement methods for each group of materials, and after completing the measurement operation, obtain multiple groups of multiple comparison measurement data; Pre-process the material by crushing it, and the pre-processed material is ready for measurement; Weigh multiple batches of materials for comparative measurement to ensure that the weights are consistent, then take a material and place it in a crucible, send the crucible containing the material into the comprehensive thermal analyzer, ensure that it is placed stably, and then seal the comprehensive thermal analyzer and wait for measurement; The initial temperature of the comprehensive thermal analyzer was set to 30°C, and after the comprehensive thermal analyzer was started, it was set to increase the temperature to 300°C at a heating rate of 25°C / min; During the temperature rising stage, operate the comprehensive thermal analyzer to inject gas, and the gas is nitrogen; The gas injection time is 2 min from the start of heating, and the gas injection time is 2 min.

[0025] Comparative Example 1 The difference between this embodiment and embodiment 1 is that in this embodiment, no pretreatment is performed on the material in step S3.

[0026] Comparative Example 2 The difference between this embodiment and embodiment 1 is that: in this embodiment, no gas injection is performed in step S3.

[0027] Data comparison: The measurement results provided by Examples 1 to 4 and Comparative Examples 1 to 2 were recorded, and the obtained measurement data were recorded in the following table, with the data unit being mg / m³: Measurement batch measurement items 1 2 3 4 5 Maximum error value Example 1 0.134 0.124 0.155 0.211 0.168 0.087 Example 2 0.128 0.123 0.165 0.185 0.123 0.062 Example 3 0.214 0.155 0.126 0.162 0.161 0.088 Example 4 0.124 0.126 0.121 0.121 0.124 0.005 Comparative Example 1 0.102 0.108 0.131 0.088 0.071 0.06 Comparative Example 2 0.135 0.221 0.156 0.322 0.126 0.196 By comparing and analyzing the relevant data in the table, it can be seen that the method for determining the formaldehyde release rate in a material based on rapid thermal analysis proposed in the present invention, in Example 4 using nitrogen injection, has a measurement result that is closer to the data measured by the traditional measurement method, and the difference in the results obtained from multiple measurements is small, indicating that the measurement result is relatively stable. At the same time, the comprehensive thermal analyzer is used for measurement, which can heat the material faster and reduce the time spent on material measurement. After nitrogen is injected into the measurement environment, nitrogen can protect formaldehyde from being oxidized by oxygen in the air, thereby reducing measurement errors and improving measurement accuracy. This shows that the method for determining the formaldehyde release rate in a material based on rapid thermal analysis provided by the present invention has higher efficiency and stability, and is more suitable for promotion.

[0028] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for determining the formaldehyde release rate in a material based on rapid thermal analysis, characterized in that: The steps include: S1: pre-treat the materials to be measured and divide the materials to be measured into several test groups; S2: The test group in step S1 is run through a comprehensive thermal analyzer to start measurement, and a heat flow curve of the comprehensive thermal analyzer is drawn.

2. The method for determining the formaldehyde release rate in a material based on rapid thermal analysis according to claim 1, characterized in that: The pretreatment in step S1 is any one of punching, rolling and crushing, and the materials after the pretreatment are ready to be grouped.

3. The method for determining the formaldehyde release rate in a material based on rapid thermal analysis according to claim 1, characterized in that: In step S2, the materials of the test group obtained in step S1 are weighed to ensure that the weight is consistent, and then one material is taken and placed in a crucible, and the crucible containing the material is sent into the comprehensive thermal analyzer. After ensuring that it is placed stably, the comprehensive thermal analyzer is sealed and waited for measurement.

4. The method for determining the formaldehyde release rate in a material based on rapid thermal analysis according to claim 1, characterized in that: The initial temperature of the comprehensive thermal analyzer in step S2 is set to 20-40°C. After the comprehensive thermal analyzer is started, the temperature is set to rise to 300°C at a heating rate of 20-30°C / min.

5. The method for determining the formaldehyde release rate in a material based on rapid thermal analysis according to claim 1, characterized in that: In step S2, during the temperature rise stage, the comprehensive thermal analyzer is operated to inject gas into the chamber, and the gas is selected from any one of air, oxygen, and nitrogen.

6. The method for determining the formaldehyde release rate in a material based on rapid thermal analysis according to claim 5, characterized in that: The gas injection time is 1-3 minutes from the start of heating.

7. The method for determining the formaldehyde release rate in a material based on rapid thermal analysis according to claim 1, characterized in that: Step S3 includes entering the data of the heat flow curve into the analysis software, smoothing and filtering the initial data for preprocessing, parsing and calculating the heat flow curve, extracting the key data in the heat flow curve, extracting the key data, and obtaining the analysis data of the comprehensive thermal analyzer based on the analysis results and data extraction records.

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