Quantitative chemical analysis method for measuring blending ratio of acetate fiber to triacetate fiber

Abstract

The invention discloses a quantitative chemical analysis method for measuring the blending ratio of acetate fiber to triacetate fiber, which comprises the following steps: putting a blended fabric piece sample into a weighing bottle, drying, cooling to room temperature, and weighing to obtain the dry mass m0 of the sample; putting the sample into a conical flask, and adding 100mL of acetone / methanol mixed solution into each gram of the sample; placing the conical flask on a constant-temperature water bath oscillation device at 48-52 DEG C for oscillation dissolution; transferring the dissolved sample together with the solution into a crucible; then cleaning residues in the crucible with absolute ethyl alcohol for 2-4 times, and then cleaning with clear water; the crucible and the residues are placed in a precise blast drying oven to be dried in the environment of 102-108 DEG C, weighing is conducted after the crucible and the residues are cooled to the room temperature, and the dry mass m1 of the residues only containing the triacetate fibers is obtained; and calculating the net dry percentage of each component in the sample through the mass loss. Compared with an existing standard test method, the method has the advantages that the usage amount of acetone is reduced, the dissolution efficiency of acetone is improved, and the test process is greatly shortened.

Description

[Technical field]

[0001] The invention relates to the technical field of textile fiber content detection, in particular to a quantitative chemical analysis method for determining the blending ratio of acetate fiber and triacetate fiber. [Background technology]

[0002] Acetate and triacetate fibers are the chemical fibers that are most similar to silk. Their fabrics have a smooth feel, bright colors, are light in texture, do not wrinkle easily and have good drape. They are widely used in men's and women's fashion, dresses, pajamas, underwear and other products, and are very popular among consumers.

[0003] At present, the test standards used for quantitative analysis of acetate and triacetate blended products are GB / T2910.8-2009 "Quantitative Chemical Analysis of Textiles Part 8: Acetate and Triacetate Mixtures (Acetone Method)" and GB / T 2910.9-2024 "Quantitative Chemical Analysis of Textiles Part 9: Mixtures of Acetate and Certain Other Fibers (Benzyl Alcohol Method)".

[0004] Among them, GB / T 2910.8-2009 stipulates that the fiber content of acetate and triacetate blended products is determined by the acetone method, that is, 70% acetone (volume fraction) solution is used to dissolve and remove acetate from a mixture of known dry mass in an oscillating water bath at room temperature, and the remaining triacetate is collected, washed, dried and weighed, and its percentage in the mixture is calculated using the corrected mass, and then the percentage of acetate is obtained from the difference. In this method, the process is not less than 1 hour, and the efficiency is low; each gram of sample requires at least 200 mL of acetone reagent, which is a large amount; and acetone has certain hazards to the environment and human body.

[0005] GB / T 2910.9-2024 stipulates that the benzyl alcohol method is used to determine the fiber content of acetate and triacetate blended products, that is, benzyl alcohol solution is used to dissolve and remove acetate from a mixture of known dry mass in a constant temperature oscillating water bath at (52±2)℃, and the remaining triacetate is collected, washed, dried and weighed, and its percentage in the mixture is calculated using the corrected mass, and the percentage of acetate is then obtained from the difference. In this method, the process is also not less than 1h, and the efficiency is low; no less than 300mL of benzyl alcohol reagent is required for each gram of sample, which is a large amount; and benzyl alcohol is harmful to the environment and human body.

[0006] In view of this, it is necessary to provide a quantitative chemical analysis method for determining the blending ratio of acetate fiber and triacetate fiber to overcome the above-mentioned defects. [Summary of the invention]

[0007] The purpose of the present invention is to provide a quantitative chemical analysis method for determining the blending ratio of acetate fiber and triacetate fiber, aiming to improve the problems of long fiber determination process, large amount of reagent used and harmful sample of existing acetate fiber and triacetate fiber blended products, and the method is more efficient and more environmentally friendly than similar methods.

[0008] In order to achieve the above object, the present invention provides a quantitative chemical analysis method for determining the blending ratio of acetate fiber and triacetate fiber, comprising:

[0009] Step S10: putting a sample of a blended fabric of acetate fiber and triacetate fiber into a weighing bottle, drying it, cooling it to room temperature, and then weighing it to obtain a dry mass m0 of the sample;

[0010] Step S20: Place the weighed sample into a conical flask, add 100 mL of acetone / methanol mixture per gram of sample, plug the flask, and carefully shake the flask to ensure that the sample is completely soaked in the solution;

[0011] Step S30: placing the conical flask on a constant temperature water bath oscillating device at 48-52° C. to oscillate and dissolve, with the oscillation frequency maintained at 60-80 times / min, and oscillating and dissolving for 19-21 min;

[0012] Step S40: the dissolved sample and the solution are transferred to a crucible, and the liquid is first drained by gravity and then by suction; then the residue in the crucible is cleaned with anhydrous ethanol for 2 to 4 times, and then cleaned with clean water for a preset number of times; wherein each cleaning is first drained by gravity and then by suction;

[0013] Step S50: Finally, the crucible and the residue are placed in a precision blast oven and dried at 102-108° C., and weighed after cooling to room temperature to obtain a dry mass m1 of the residue containing only triacetate fiber;

[0014] Step S60: Calculate the net dry percentage of each component in the sample by mass loss; wherein the calculation formula is as follows:

[0015] P1=1-P2; m0 is the dry mass of the blended fabric sample before dissolution, m1 is the dry mass of the triacetate fiber after dissolution, d is the mass correction coefficient of the triacetate fiber in the acetone / methanol solution obtained in advance, P1 is the net dry percentage content of the acetate fiber, and P2 is the net dry percentage content of the triacetate fiber.

[0016] In a preferred embodiment, in step S10, after the blended fabric sample is disassembled into yarns, two portions are taken as parallel samples, and then both are tested according to steps S10-S50 to obtain two groups of net dry percentage data of each component, and then the average value is taken.

[0017] In a preferred embodiment, the method further comprises the steps of:

[0018] A preset number of triacetate fiber samples are taken as parallel samples, and the test is performed according to the steps S10-S50, and the calculation is performed according to the calculation formula of the mass correction coefficient d, which is as follows:

[0019] Here, m0 is the dry mass of triacetate fiber before dissolution, and m1 is the dry mass of triacetate fiber after dissolution.

[0020] In a preferred embodiment, the method further comprises the steps of:

[0021] Prepare acetone / methanol mixed solution: mix acetone and methanol solution in a volume ratio of 45:55.

[0022] In a preferred embodiment, in the step S10, it further includes:

[0023] The sample was split into yarns of 2 to 5 cm in length and placed in a weighing bottle.

[0024] The quantitative chemical analysis method for determining the blending ratio of acetate fiber and triacetate fiber provided by the present invention adopts a dissolution system of an acetone / methanol mixed solution. In the dissolution system, acetone acts directly on acetate fiber as a true solvent, and methanol acts as a co-solvent to improve the dissolution efficiency of the acetone solvent, thereby achieving the effect of quantitative analysis. Compared with the current standard test method, the present invention reduces the amount of acetone used, improves the dissolution efficiency of acetone, and greatly shortens the test process; at the same time, it ensures that the mass loss of the remaining fiber (triacetate fiber) in the dissolution system is controllable, thereby effectively improving the accuracy of the data.

Brief Description of the Drawings

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 The present invention provides a flow chart of a quantitative chemical analysis method for determining the blending ratio of acetate fiber and triacetate fiber. [Specific implementation method]

[0027] In order to make the purpose, technical solution and beneficial technical effect of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the specific implementation methods described in this specification are only for explaining the present invention, not for limiting the present invention.

[0028] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0029] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0030] In an embodiment of the present invention, a quantitative chemical analysis method for determining the blending ratio of acetate fiber to triacetate fiber is provided, which is used to dissolve and remove acetate fiber from a mixture from which non-fibrous materials have been removed using an acetone / methanol solution, collect the residue, wash, dry and weigh it; use the corrected mass to calculate its percentage of the dry mass of the mixture, and then use the difference to determine the mass percentage of acetate fiber.

[0031] It should be noted that before testing, the following samples and reagents can be prepared:

[0032] (1) Acetate fiber: standard interlining fabric;

[0033] (2) Triacetate fiber: test sample (insoluble in benzyl alcohol and 70% acetone, melting point 305°C);

[0034] (3) Acetate and triacetate blended fabric;

[0035] (4) Acetone / methanol mixed solution: acetone and methanol solution were mixed uniformly in a volume ratio of 45:55;

[0036] (5) Anhydrous ethanol;

[0037] (6) Precision blast oven: 105±3℃;

[0038] (7) Electronic balance: accuracy 0.0001g;

[0039] (8) Conical flask with stopper: capacity not less than 250 mL;

[0040] (9) Constant temperature water bath oscillating device: can maintain (50±2)℃, oscillation frequency 60 to 100 times / min.

[0041] like Figure 1 As shown, the method includes steps S10-S60.

[0042] Step S10: Put the acetate fiber and triacetate fiber blended cloth sample into a weighing bottle, dry it, cool it to room temperature, and then weigh it to obtain the dry mass m0 of the sample.

[0043] In this step, the sample is split into 2-5 cm long yarns and then placed in a weighing bottle. Furthermore, after the blended fabric sample is split into yarns, two portions are taken as parallel samples, and then both are tested according to the same steps to obtain the net dry percentage data of each component in two groups, and then the average value is taken to improve the accuracy of the test.

[0044] Step S20: Place the weighed sample into a conical flask, add 100 mL of acetone / methanol mixture per gram of sample, plug the flask, and carefully shake the flask to ensure that the sample is completely soaked in the solution.

[0045] The acetone / methanol mixed solution is obtained by uniformly mixing acetone and methanol solution in a volume ratio of 45:55.

[0046] Step S30: placing the conical flask on a constant temperature water bath oscillating device at 48-52°C for oscillation and dissolution, maintaining the oscillation frequency at 60-80 times / min, and oscillating and dissolving for 19-21 minutes.

[0047] Step S40: Move the dissolved sample together with the solution into a crucible (e.g., a glass crucible), drain the solution by gravity first and then by suction; then use anhydrous ethanol to clean the residue in the crucible for 2 to 4 times, and then use clean water to clean the crucible for a preset number of times (i.e., perform multiple cleanings); wherein, each cleaning is drained by gravity first and then by suction.

[0048] Step S50: Finally, the crucible and the residue are placed in a precision blast oven and dried at 102-108° C., cooled to room temperature, and weighed to obtain a dry mass m1 of the residue containing only triacetate fiber.

[0049] Step S60: Calculate the net dry percentage of each component in the sample by mass loss; wherein the calculation formula is as follows:

[0050] P1=1-P2; m0 is the dry mass of the blended fabric sample before dissolution, in g; m1 is the dry mass of the triacetate fiber after dissolution, in g; d is the mass correction coefficient of the triacetate fiber in the acetone / methanol solution obtained in advance, P1 is the net dry percentage content of the acetate fiber, and P2 is the net dry percentage content of the triacetate fiber.

[0051] Specifically, the method further includes the steps of taking a preset number (e.g., ten) of triacetate fiber samples as parallel samples, performing the test according to the steps S10-S50, and performing the calculation according to the calculation formula of the mass correction coefficient d, which is as follows: Here, m0 is the dry mass of triacetate fiber before dissolution, and m1 is the dry mass of triacetate fiber after dissolution.

[0052] In an exemplary embodiment, ten triacetate fiber samples are taken as parallel samples, each weighing about 1 gram. The test is carried out according to the above steps, and the data and result calculations are shown in Table 1 below.

[0053] Table 1: Test results of correction value d

[0054]

[0055] From the data in the table, we can see that in the acetone / methanol mixed solution method, the average value of the mass correction coefficient d of triacetate fiber is 1.0180, and the value retained to three significant figures is 1.02; the standard deviation S of this test is 0.0010, and at the 95% confidence level, its confidence limit is ±0.0007, indicating that all tests fall within a small range, indicating that the test has good reproducibility.

[0056] The following is a comparison test between this method and the current standard method, in which the blended samples tested by each method are consistent. Table 2 shows the test results of each method.

[0057] Table 2: Comparison test results between this method and the current standard method

[0058]

[0059] It can be seen from the data in the table that the standard deviations of the three methods for measuring different samples are no more than 0.3, which meets the precision requirements of general test methods; the maximum content difference between the mean of each test method and the true value of the sample is 1.33, which meets the content tolerance requirements specified in GB / T 29862.

[0060] In summary, the quantitative chemical analysis method for determining the blending ratio of acetate fiber and triacetate fiber provided by the present invention adopts a dissolution system of an acetone / methanol mixed solution. In the dissolution system, acetone acts directly on the acetate fiber as a true solvent, and methanol acts as a co-solvent to improve the dissolution efficiency of the acetone solvent, thereby achieving the effect of quantitative analysis. Compared with the current standard test method, the present invention reduces the amount of acetone used, improves the dissolution efficiency of acetone, and greatly shortens the test process; at the same time, it ensures that the mass loss of the remaining fiber (triacetate fiber) in the dissolution system is controllable, thereby effectively improving the accuracy of the data.

[0061] The present invention is not limited to what is described in the specification and implementation modes, and therefore additional advantages and modifications can be easily realized by those skilled in the art. Therefore, without departing from the spirit and scope of the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details, representative devices, and illustrative examples shown and described herein.

Claims

1. A quantitative chemical analysis method for determining the blending ratio of acetate fiber and triacetate fiber, characterized in that: include: Step S10: putting a sample of a blended fabric of acetate fiber and triacetate fiber into a weighing bottle, drying it, cooling it to room temperature, and then weighing it to obtain a dry mass m0 of the sample; Step S20: Place the weighed sample into a conical flask, add 100 mL of acetone / methanol mixture per gram of sample, plug the flask, and carefully shake the flask to ensure that the sample is completely soaked in the solution; Step S30: placing the conical flask on a constant temperature water bath oscillating device at 48-52° C. to oscillate and dissolve, with the oscillation frequency maintained at 60-80 times / min, and oscillating and dissolving for 19-21 min; Step S40: moving the dissolved sample together with the solution into a crucible, draining the solution by gravity first and then by suction; Then, the residue in the crucible is cleaned with anhydrous ethanol for 2 to 4 times, and then cleaned with clean water for a preset number of times; wherein, each cleaning is first drained by gravity and then by suction; Step S50: Finally, the crucible and the residue are placed in a precision blast oven and dried at 102-108° C., and weighed after cooling to room temperature to obtain a dry mass m1 of the residue containing only triacetate fiber; Step S60: Calculate the net dry percentage of each component in the sample by mass loss; wherein the calculation formula is as follows: P1=1-P2; m0 is the dry mass of the blended fabric sample before dissolution, m1 is the dry mass of the triacetate fiber after dissolution, d is the mass correction coefficient of the triacetate fiber in the acetone / methanol solution obtained in advance, P1 is the net dry percentage content of the acetate fiber, and P2 is the net dry percentage content of the triacetate fiber.

2. The quantitative chemical analysis method for determining the blending ratio of acetate fiber and triacetate fiber according to claim 1, characterized in that: In the step S10, after the blended fabric sample is disassembled into yarns, two portions are taken as parallel samples, and then both are tested according to the steps S10-S50 to obtain two groups of net dry percentage data of each component, and then take the average value.

3. The quantitative chemical analysis method for determining the blending ratio of acetate fiber and triacetate fiber according to claim 1, characterized in that: Also includes the steps: A preset number of triacetate fiber samples are taken as parallel samples, and the test is performed according to the steps S10-S50, and the calculation is performed according to the calculation formula of the mass correction coefficient d, which is as follows: Here, m0 is the dry mass of triacetate fiber before dissolution, and m1 is the dry mass of triacetate fiber after dissolution.

4. The quantitative chemical analysis method for determining the blending ratio of acetate fiber and triacetate fiber according to claim 1, characterized in that: Also includes the steps: Prepare acetone / methanol mixed solution: mix acetone and methanol solution in a volume ratio of 45:

55.

5. The quantitative chemical analysis method for determining the blending ratio of acetate fiber and triacetate fiber according to claim 1, characterized in that: In the step S10, it also includes: The sample was split into yarns of 2 to 5 cm in length and placed in a weighing bottle.

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