Alizarin Yellow R functionalized acrylic fiber and preparation method and application thereof

Abstract

The present invention relates to a preparation method and application of Alizarin Yellow R functionalized acrylic fiber, belonging to the technical field of acid-base indication. The present invention aims to solve the problem that small molecule acid-base indicators cannot be separated from a solution, and for a system with high requirements, they will cause certain pollution to the solution after determination. In addition, some acid-base indicators are expensive and have a complicated preparation process, and the disadvantage that they are difficult to recycle further increases the application cost of these small molecule acid-base indicators. The characteristics mainly include the following two steps: 1. Pretreatment of commercial acrylic fiber; 2. Preparation of ethanolamine functionalized acrylic fiber; 3. Preparation of Alizarin Yellow R functionalized acrylic fiber. The preparation method of the solid acid-base indicator is simple, the acid-base color change is sensitive, and it also shows excellent recycling performance, and has good industrial application value.

Description

Technical Field

[0001] The invention belongs to the technical field of acid-base color change indication, and relates to an Alizarin Yellow R functionalized acrylic fiber and a preparation method and application thereof. Background Art

[0002] Acid-base wastewater mainly comes from metallurgy, petrochemical industry, papermaking and other industries. When it enters the water, it will destroy the natural neutralization effect, affect the normal growth of aquatic organisms, and reduce the self-purification function of the water body; when it penetrates into the soil, it will destroy the physical and chemical properties of the soil, causing soil acidification or alkalinization, affecting the normal growth of crops. Monitoring pH changes is very important in life and scientific research, but common monitoring methods are generally complicated to operate or require high instrumentation and equipment. Therefore, it is particularly important to monitor acid-base changes through simple methods (such as color changes).

[0003] Traditional small molecule acid-base indicators have advantages such as high sensitivity and significant color change, but they cannot be separated from the solution, and for systems with high requirements, they will cause certain contamination to the solution after measurement. In addition, some acid-base indicators are expensive and have complex preparation processes, and their difficulty in recycling further increases the application cost of these small molecule acid-base indicators.

[0004] In recent years, many immobilized reusable acid-base color-changing sensor materials have been used in the field of pH monitoring and practical applications. However, these acid-base color-changing materials are currently mainly used in the form of nanomaterials, granular materials, membrane materials, etc., and most of these materials are costly, complex in preparation, and have unsatisfactory repeatability, making them difficult to be widely used. In the context of green chemistry and carbon neutrality, the present invention provides a acrylic-based recyclable flexible acid-base color-changing material through technological innovation of acid-base indicator materials, which solves the problems of high preparation cost, complex production, unsatisfactory repeatability or complex operation, and high requirements for instruments and equipment for common pH detection materials, while reducing costs and optimizing the actual operating experience. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention proposes an Alizarin Yellow R functionalized acrylic fiber with a cheap and easily available carrier, a simple preparation process, sensitive acid-base color change, low cost, and good recycling performance, as well as a preparation method and application thereof. The obtained Alizarin Yellow R functionalized acrylic fiber is used as a new type of solid-supported acid-base color change indicator to solve the problems of existing small molecule acid-base indicators that cannot be recycled, pollute the environment, and have high costs.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A method for preparing Alizarin Yellow R functionalized acrylic fiber comprises the following steps:

[0008] (1) Pretreatment of commercial acrylic fiber: Place commercial polyvinyl alcohol fiber in distilled water and react under magnetic stirring. After the reaction, filter, rinse with distilled water, and dry for later use.

[0009] (2) Preparation of ethanolamine functionalized acrylic fiber: The acrylic fiber treated in step (1) is added to a mixture of ethanolamine and water for reaction. After the reaction is completed, the fiber is taken out and repeatedly washed with warm water until neutral, and then dried to obtain ethylene glycol functionalized acrylic fiber PAN. E F;

[0010] (3) Preparation of Alizarin Yellow R functionalized acrylic fiber: Add ethylene glycol functionalized acrylic fiber PAN into a round bottom flask. E F, then add Alizarin Yellow R, concentrated phosphoric acid and distilled water to react, filter after the reaction, wash the obtained fiber repeatedly with warm water until the filtrate does not show color under ultraviolet light, and finally dry to obtain Alizarin Yellow R functionalized acrylic fiber PAN E F-MO.

[0011] Furthermore, the reaction temperature of step (1) is 50-100°C, and the reaction time is 2-10 h.

[0012] Furthermore, in step (2), the volume ratio of ethanolamine to water is 3:1 to 1:5. Based on 1 g of the acrylic fiber treated in step (1), 50 mL of a mixture of ethanolamine and water is required.

[0013] Furthermore, in step (2), the reaction temperature is 60-120° C., and the reaction time is 1-8 h.

[0014] Further, in step (3), 0.5 g of ethylene glycol was used to functionalize acrylic fiber PAN E F as the base, add 0.2~1.5 g of Alizarin Yellow R, 0.5~2 mL of concentrated phosphoric acid, and 20~60 mL of distilled water.

[0015] Furthermore, in step (3), the reaction temperature is preferably 60-120° C., and the reaction time is 4-10 h.

[0016] Furthermore, the temperature of the warm water in step (2) and step (3) is 60-80°C.

[0017] Furthermore, the drying in step (2) and step (3) is carried out in a drying oven at 60° C. for 12 h.

[0018] The Alizarin Yellow R functionalized acrylic fiber is prepared by the preparation method of the invention.

[0019] Application of the Alizarin Yellow R functionalized acrylic fiber of the present invention in acid-base detection.

[0020] After adopting the above technical solution, the present invention achieves the following beneficial effects:

[0021] (1) The present invention is the first to prepare a solid-supported Alizarin Yellow R indicator using commercial acrylic fiber as a carrier. The solid indicator carrier is cheap and readily available, has a simple preparation process, high acid-base color change sensitivity, low cost, and good recycling performance. It effectively solves the problems of existing small molecule indicators that are non-recyclable, pollute the environment, and are high in cost.

[0022] (2) The Alizarin Yellow R functionalized acrylic fiber (PAN) prepared by the present invention E F-MO) is used to determine the acidity and alkalinity of aqueous solutions. E F-MO fiber is bright yellow in acid or neutral solution and turns brown-red in alkaline solution. It is very sensitive to alkali. 0.1-2.0 mol / L sodium hydroxide solution can make it change from yellow to brown-red within 1 s. Moreover, it is also very sensitive to color change in low concentration alkali, even at 7×10 -4 mol / L sodium hydroxide solution will still change color within 2 s. E F-MO has excellent cycling performance. After 500 cycles of color change in 0.1 mol / L alkali, the fiber can still change color quickly.

[0023] (3) The Alizarin Yellow R functionalized acrylic fiber (PAN) prepared by the present invention E F-MO) is used as an indicator in acid-base titration. E F-MO was placed in 20.00 mL of a certain concentration of HCl aqueous solution. The concentration of the HCl aqueous solution was determined by 0.100 mol / L NaOH solution, which was 0.109 mol / L. This was basically consistent with the result of using phenolphthalein as an indicator (0.108 mol / L). Figure 7 ), indicating that the Alizarin Yellow R functionalized acrylic fiber prepared by the present invention has good substitution properties for small molecule indicators. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Alizarin Yellow R functionalized acrylic fiber PAN E Synthesis route of F-MO.

[0025] Figure 2 The Alizarin Yellow R functionalized acrylic fiber PAN prepared in Example 1 E The color change of F-MO in acid and alkali.

[0026] Figure 3 The Alizarin Yellow R functionalized acrylic fiber PAN prepared in Example 1 E Color change of F-MO in different concentrations of alkali.

[0027] Figure 4 The Alizarin Yellow R functionalized acrylic fiber PAN prepared in Example 1 E F-MO changes color 500 times in 0.1 mol / L alkali.

[0028] Figure 5 The Alizarin Yellow R functionalized acrylic fiber PAN prepared in Example 1 E Color change of F-MO in different acids.

[0029] Figure 6 The Alizarin Yellow R functionalized acrylic fiber PAN prepared in Example 1 E Color change of F-MO in different alkalis.

[0030] Figure 7 The Alizarin Yellow R functionalized acrylic fiber PAN prepared in Example 1 E Determination of the stability of F-MO against strong acids and alkalis. DETAILED DESCRIPTION

[0031] The present invention will be further described below in conjunction with specific embodiments. It should be understood that the following embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention, and those skilled in the art in this field can make some non-essential improvements and adjustments based on the content of the above invention.

[0032] Example 1

[0033] The preparation method of the functionalized acrylic fiber of Alizarin Yellow R in this embodiment is as follows:

[0034] (1) Pretreatment of commercial acrylic fiber: 5.0 g of commercial polyvinyl alcohol fiber was placed in a 500 mL round-bottom flask containing 300 mL of distilled water and stirred at 100 °C. o C for 5 h, filter, and rinse with 200 mL of 60-80°C distilled water. o C Dry in a drying oven for later use.

[0035] (2) Preparation of ethanolamine functionalized acrylic fiber: Add 1.0 g of the acrylic fiber treated in step 1 to 50 mL of a mixture of ethanolamine and water (volume ratio) = 2:3. After the reaction mixture was reacted at 105°C for 4 h, the fiber was taken out and repeatedly washed with warm water (60-80°C) until neutral, and then dried in a drying oven at 60°C for 12 h to obtain ethylene glycol functionalized acrylic fiber PAN. E F.

[0036] (3) Preparation of Alizarin Yellow R functionalized acrylic fiber: Add 0.5 g PAN into a 100 mL round-bottom flask. EF, then add 0.5 g of Alizarin Yellow R, 0.5 mL of concentrated phosphoric acid and 20 mL of distilled water, react at 105 ° C for 6 h, filter, and wash the fiber repeatedly with warm water (60-80 ° C) until the filtrate does not show color under ultraviolet light. Finally, dry it in a drying oven at 60 ° C for 12 h to obtain Alizarin Yellow R functionalized acrylic fiber (PAN E F-MO).

[0037] The above-mentioned Alizarin Yellow R functionalized acrylic fiber (PAN E F-MO) is used for acid-base detection according to the following scheme.

[0038] 0.05 g PAN E F-MO was placed in 5 mL of an acid or alkali solution of a certain concentration, and the color change of the fiber was observed after 1 second. If the fiber was yellow, the solution was acidic or neutral; if the fiber turned reddish brown, the solution was alkaline.

[0039] Figure 2 PAN E The color change of F-MO in acid and alkali is determined by Figure 2 It can be seen that the fiber is yellow in acid solution and brown-red in alkaline solution. Figure 3 PAN E The color change of F-MO in different concentrations of alkali is determined by Figure 3 It can be seen that the fiber is brown-red in different concentrations of sodium hydroxide solution, and the fiber is brown-red in the concentration as low as 7×10 -4 mol / L, color change can still occur. Figure 4 PAN E F-MO changes color 500 times in 0.1 mol / L alkali. Figure 4 It can be seen that after 500 cycles, the fiber can still change color rapidly in the alkaline solution, which is basically indistinguishable from the newly made fiber. Figure 5 PAN E The color change of F-MO in different acids is determined by Figure 5 It can be seen that yellow color can be seen in different acids, indicating that it has good acid universality. Figure 6 PAN E The color change of F-MO in different alkalis is determined by Figure 6 It can be seen that the fiber can undergo a brown-red change in different alkaline solutions, indicating that it has good alkali universality. Figure 7 PAN E F-MO strong acid and alkali stability test, by Figure 7 It can be seen that the fiber can still show color normally after being placed in saturated sodium hydroxide solution and 9 mol / L hydrochloric acid solution for 24 h respectively.

[0040] The xylenol orange functionalized polyvinyl alcohol fiber (PVAF-XO) was applied to acid-base titration according to the following protocol.

[0041] 0.05 g PAN E F-MO was placed in 25 mL of hydrochloric acid solution of a certain concentration, and the concentration of the hydrochloric acid solution was calibrated with 0.102 mol / L sodium hydroxide solution. The titration was stopped when the fiber changed from yellow to reddish brown, and the consumption of sodium hydroxide solution was recorded. After three parallel titrations, the concentration of the hydrochloric acid solution was calculated.

[0042] The experimental results are shown in Table 1.

[0043] Table 1 PAN prepared in Example 1 E Titration results of F-MO replacing phenolphthalein as acid-base indicator

[0044] Experiment number Alkali concentration (mol / L) Indicator Determine acid concentration (mol / L) 1 0.102 Phenolphthalein 0.108 2 0.102 <![CDATA[PAN E F-MO]]> 0.109

[0045] Example 2

[0046] The preparation method of the functionalized acrylic fiber of Alizarin Yellow R in this embodiment is as follows:

[0047] (1) Pretreatment of commercial acrylic fiber: 5.0 g of commercial polyvinyl alcohol fiber was placed in a 500 mL round-bottom flask containing 300 mL of distilled water and stirred at 50 °C. o C for 10 h, filter, and rinse with 200 mL of 60-80°C distilled water. o C Dry in a drying oven for later use.

[0048] (2) Preparation of ethanolamine functionalized acrylic fiber: Add 1.0 g of the acrylic fiber treated in step 1 to 50 mL of a mixture of ethanolamine and water (volume ratio) = 3:1. After the reaction mixture is reacted at 60°C for 8 h, the fiber is taken out and repeatedly washed with warm water (60-80°C) until neutral, and then dried in a drying oven at 60°C for 12 h to obtain ethylene glycol functionalized acrylic fiber PAN. E F.

[0049] (3) Preparation of Alizarin Yellow R functionalized acrylic fiber: Add 0.5 g PAN into a 100 mL round-bottom flask. E F, then add 0.2 g of Alizarin Yellow R, 1 mL of concentrated phosphoric acid and 30 mL of distilled water, react at 60 ° C for 10 h, filter, and wash the fiber repeatedly with warm water (60-80 ° C) after the reaction until the filtrate does not show color under ultraviolet light. Finally, dry it in a drying oven at 60 ° C for 12 h to obtain Alizarin Yellow R functionalized acrylic fiber.

[0050] Example 3

[0051] The preparation method of the functionalized acrylic fiber of Alizarin Yellow R in this embodiment is as follows:

[0052] (1) Pretreatment of commercial acrylic fiber: 5.0 g of commercial polyvinyl alcohol fiber was placed in a 500 mL round-bottom flask containing 300 mL of distilled water and stirred at 80 °C. o C for 8 h, filter, and rinse with 200 mL of 60-80°C distilled water. o C Dry in a drying oven for later use.

[0053] (2) Preparation of ethanolamine functionalized acrylic fiber: Add 1.0 g of the acrylic fiber treated in step 1 to a mixture of 50 mL of ethanolamine: water (volume ratio) = 1:5. After the reaction mixture is reacted at 120°C for 1 h, the fiber is taken out and repeatedly washed with warm water (60-80°C) until neutral, and then dried in a drying oven at 60°C for 12 h to obtain ethylene glycol functionalized acrylic fiber PAN. E F.

[0054] (3) Preparation of Alizarin Yellow R functionalized acrylic fiber: Add 0.5 g PAN into a 100 mL round-bottom flask. E F, then add 1.5 g of Alizarin Yellow R, 2 mL of concentrated phosphoric acid and 60 mL of distilled water, react at 120 ° C for 4 h, filter, and wash the fiber repeatedly with warm water (60-80 ° C) after the reaction until the filtrate does not show color under ultraviolet light, and finally dry it in a drying oven at 60 ° C for 12 h to obtain Alizarin Yellow R functionalized acrylic fiber.

[0055] The above shows and describes the basic principles and main features of the present invention and the 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 to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for preparing Alizarin Yellow R functionalized acrylic fiber, characterized in that: The following steps are involved: (1) Pretreatment of commercial acrylic fiber: Place the commercial acrylic fiber in distilled water and react under magnetic stirring. After the reaction, filter, rinse with distilled water, and dry for later use. (2) Preparation of ethanolamine functionalized acrylic fiber: Add the acrylic fiber treated in step (1) into a mixture of ethanolamine and water for reaction. After the reaction is completed, take out the fiber and wash it repeatedly with warm water until it is neutral, and dry it to obtain ethanolamine functionalized acrylic fiber PAN. E F; (3) Preparation of Alizarin Yellow R functionalized acrylic fiber: Add ethanolamine functionalized acrylic fiber PAN into a round bottom flask. E F, then add Alizarin Yellow R, concentrated phosphoric acid and distilled water to react, filter after the reaction, wash the obtained fiber repeatedly with warm water until the filtrate does not show color under ultraviolet light, and finally dry to obtain Alizarin Yellow R functionalized acrylic fiber PAN E F-MO.

2. The method for preparing the Alizarin Yellow R functionalized acrylic fiber according to claim 1, wherein: The reaction temperature of step (1) is 50-100°C and the reaction time is 2-10 h.

3. The method for preparing the Alizarin Yellow R functionalized acrylic fiber according to claim 1, wherein: In step (2), the volume ratio of ethanolamine to water is 3:1 to 1:

5. Based on 1 g of the acrylic fiber treated in step (1), 50 mL of a mixture of ethanolamine and water is required.

4. The method for preparing the Alizarin Yellow R functionalized acrylic fiber according to claim 1, wherein: In step (2), the reaction temperature is 60-120° C. and the reaction time is 1-8 h.

5. The method for preparing the Alizarin Yellow R functionalized acrylic fiber according to claim 1, characterized in that: In step (3), 0.5 g of ethanolamine was used to functionalize acrylic fiber PAN E F as the base, add 0.2~1.5 g of Alizarin Yellow R, 0.5~2 mL of concentrated phosphoric acid, and 20~60 mL of distilled water.

6. The method for preparing the Alizarin Yellow R functionalized acrylic fiber according to claim 1, characterized in that: In step (3), the reaction temperature is preferably 60-120° C., and the reaction time is 4-10 h.

7. The method for preparing the Alizarin Yellow R functionalized acrylic fiber according to claim 1, characterized in that: The temperature of the warm water in step (2) and step (3) is 60-80°C.

8. The method for preparing the Alizarin Yellow R functionalized acrylic fiber according to claim 1, characterized in that: The drying in step (2) and step (3) is carried out in a drying oven at 60°C for 12 h.

9. Alizarin Yellow R functionalized acrylic fiber obtained by the preparation method according to any one of claims 1 to 8.

10. Use of the Alizarin Yellow R functionalized acrylic fiber according to claim 9 in acid-base detection.

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