CN115450045B - Flame retardant, washable flame-retardant cotton fabric, preparation method and application thereof - Google Patents

Abstract

The application discloses a flame retardant, a washable flame-retardant cotton fabric, a preparation method and application thereof. The flame retardant of the application comprises the following components: graphene oxide, phosphoric acid, urea, guanidine phosphate, dicyandiamide and an aqueous solvent; in the flame retardant, the concentration of graphene oxide is 8-10 mg/ml, the concentration of phosphoric acid is 56-84 mg/ml, the concentration of urea is 34-86 mg/ml, the concentration of guanidine phosphate is 22-65 mg/ml, and the concentration of dicyandiamide is 25-75 mg/ml. The flame retardant is combined with cotton fabric fiber molecules in a multiple bonding mode to form the washable flame-retardant cotton fabric with a three-dimensional penetrating structure. The washable flame-retardant cotton fabric prepared by the method has excellent flame retardant property, LOI (Low-loss-of-ignition) after 50 times of washing can still reach 32.8%, has excellent flame retardant property and washable property, and is simple in preparation process, environment-friendly in preparation process and easy to realize large-scale production.

Description

A kind of flame retardant, water-resistant flame-retardant cotton fabric, preparation method and application thereof

Technical field

This application belongs to the technical field of functional textiles, and specifically relates to a flame retardant, washable flame retardant cotton fabric, preparation method and application.

Background technique

A large number of fire accidents occur around the world every year, causing serious harm to human life, and a large number of fire accidents are caused by flammable textiles. Cotton fabric has excellent properties such as good breathability, comfort, hydrophilicity and biodegradability, and is widely used in the textile and clothing industries. However, its limiting oxygen index (LOI) is only about 18%, making it flammable. Therefore, it will be a very practical research topic to prepare cotton fabrics with flame retardant properties and reduce the fire hazards that may be caused by cotton fabrics during use.

Cotton fabrics are natural fiber textiles. To give cotton fabrics flame retardant function, the most widely used method is to use flame retardants to post-process cotton fabrics, that is, through layer-by-layer self-assembly method, chemical grafting method, sol-gel method and Physical adhesion fixes the flame retardant on the surface of the fabric, so that the cotton fabric has good flame retardant properties. However, post-processed flame retardant cotton fabrics usually have washing resistance problems that cannot be ignored. For example, in patent CN 109183408A, a flame-retardant cotton fabric is prepared using a layer-by-layer self-assembly method using polycationic sol and anionic solution. Although the prepared flame-retardant cotton fabric has good flame-retardant effect, the preparation process is simple, and it is green and environmentally friendly. The water-washing resistance of the flame-retardant cotton fabric prepared by this method is not significant. For example, in patent CN110117899A, KH570 is used to surface modify attapulgite (ATP), and then KH590 is used to graft cotton fabric. Finally, ATP is grafted to the surface of cotton fabric through sulfide-ene click reaction under UV light irradiation to prepare Flame-retardant cotton fabric, the obtained cotton fabric has excellent flame-retardant properties, but the preparation method is complicated, and the washing resistance of the final flame-retardant cotton fabric is not clear yet.

Contents of the invention

The purpose of this application is to overcome the shortcomings of the existing technology and provide a flame retardant, water-resistant flame-retardant cotton fabric, preparation method and application thereof, so as to solve the complex preparation process, low flame-retardant efficiency and water-wash resistance of traditional flame-retardant cotton fabrics. Poor technical issues.

In order to achieve the above application purpose, the first aspect of this application provides a flame retardant containing the following components: graphene oxide, phosphoric acid, urea, guanidine phosphate, dicyandiamide and water solvent; in the flame retardant, The concentration of graphene oxide is 8 to 10 mg/ml, the concentration of phosphoric acid is 56 to 84 mg/ml, the concentration of urea is 34 to 86 mg/ml, and the concentration of guanidine phosphate is 22 to 65 mg/ml. , the concentration of dicyandiamide is 25 to 75 mg/ml.

A second aspect of the application provides a method for preparing a flame retardant, which includes the following steps: mixing graphene oxide solution, phosphoric acid, urea, guanidine phosphate and dicyandiamide to prepare a flame retardant;

In the flame retardant, the concentration of graphene oxide is 8-10 mg/ml, the concentration of phosphoric acid is 56-84 mg/ml, the concentration of urea is 34-86 mg/ml, and the concentration of guanidine phosphate is The concentration is 22-65 mg/ml, and the concentration of dicyandiamide is 25-75 mg/ml.

The third aspect of this application provides the application of a flame retardant on cotton fabrics.

The fourth aspect of the present application provides a washable flame-retardant cotton fabric. The surface of the washable flame-retardant cotton fabric contains a flame retardant. The flame retardant contains the following components: graphene oxide, phosphoric acid, urea, Guanidine phosphate, dicyandiamide and water solvent; in the flame retardant, the concentration of graphene oxide is 8-10 mg/ml, the concentration of phosphoric acid is 56-84 mg/ml, and the concentration of urea is 34 ~86mg/ml, the concentration of guanidine phosphate is 22~65mg/ml, and the concentration of dicyandiamide is 25~75mg/ml.

The fifth aspect of this application provides a method for preparing a washable flame-retardant cotton fabric, including the following steps:

Pretreatment of cotton fabric surface;

Prepare a flame retardant containing graphene oxide solution, phosphoric acid, urea, guanidine phosphate and dicyandiamide; in the flame retardant, the concentration of the graphene oxide is 8-10 mg/ml, and the concentration of the phosphoric acid is 56 ~84mg/ml, the concentration of urea is 34~86mg/ml, the concentration of guanidine phosphate is 22~65mg/ml, and the concentration of dicyandiamide is 25~75mg/ml;

The flame retardant is impregnated or coated on the surface of the pre-treated cotton fabric, and after drying treatment, a washable flame-retardant cotton fabric is obtained.

Further, the pretreatment process is as follows: soaking the cotton fabric in an alkaline solution, then washing it with water until it is neutral and drying it.

Further, the alkaline solution is sodium hydroxide solution or potassium hydroxide solution.

Further, the concentration of the alkaline solution is 0.5-2 mol/L.

Further, the temperature of the drying treatment is 150-170°C, and the time is 6-10 minutes.

Compared with the existing technology, this application has the following technical effects:

A kind of flame retardant in this application introduces graphene oxide as the carbon source in the intumescent flame retardant. Graphene oxide can act as a barrier to the transmission of heat and materials during the combustion process, and can combine acid sources and nitrogen sources. It synergistically exerts a flame retardant effect, which is beneficial to improving the flame retardant performance and washing resistance of cotton fabrics.

The preparation method of the flame retardant of the present application is simple, the preparation cost is low, the preparation process is green and environmentally friendly, and it is easy to realize large-scale production.

The water-resistant flame-retardant cotton fabric of this application is coated on the surface of the cotton fabric with a flame retardant containing graphene oxide, phosphoric acid, urea, guanidine phosphate and dicyandiamide. The flame retardant constructs a flame retardant during the high-temperature drying process. Covalent grafting between the agent and cotton fabric fiber molecules (P-O-C and C=N-C grafting), while self-assembly can occur between graphene oxide and cotton fiber molecules in the flame retardant system, producing a "three-dimensional penetration" "Structural" water-resistant flame-retardant cotton fabric simultaneously achieves the flame-retardant properties and wash-resistant properties of cotton fabrics.

The preparation method of the washable flame-retardant cotton fabric of the present application is simple, the preparation cost is low, the preparation process is green and environmentally friendly, and it is easy to realize large-scale production.

Description of the drawings

In order to more clearly explain the specific embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description The drawings illustrate some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting creative efforts.

Figure 1 is a schematic diagram of the combination between the flame retardant and cotton fabric fiber molecules provided by the embodiment of the present application;

Figure 2 shows the pure cotton fabric before (a) (b) and after (c) (d) burning and the washable flame-retardant cotton fabric prepared in Example 3 of the present application before (e) (f) and after (g) ( h) SEM morphology picture.

Detailed ways

In order to make the technical problems, technical solutions and beneficial effects to be solved by this application clearer, this application will be further described in detail below in conjunction with examples. It should be understood that the specific embodiments described here are only used to explain the present application and are not used to limit the present application.

In this application, the term "and/or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and/or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. Condition. Where A and B can be singular or plural. The character "/" generally indicates that the related objects are in an "or" relationship.

In this application, "at least one" refers to one or more, and "plurality" refers to two or more. "At least one of the following" or similar expressions thereof refers to any combination of these items, including any combination of a single item (items) or a plurality of items (items). For example, "at least one of a, b, or c", or "at least one of a, b, and c" can mean: a, b, c, a-b ( That is, a and b), a-c, b-c, or a-b-c, where a, b, and c can be single or multiple respectively.

It should be understood that in various embodiments of the present application, the size of the sequence numbers of the above-mentioned processes does not mean the order of execution. Some or all steps can be executed in parallel or one after another. The execution order of each process should be based on its function and order. The internal logic is determined and should not constitute any limitation on the implementation process of the embodiments of the present application.

The terminology used in the embodiments of the present application is only for the purpose of describing specific embodiments and is not intended to limit the present application. As used in the embodiments and the appended claims, the singular forms "a," "the" and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise.

The weights of relevant components mentioned in the description of the embodiments of the present application may not only refer to the specific content of each component, but also represent the proportional relationship of weight between the components. Therefore, as long as the relevant components are combined according to the description of the embodiments of the present application, Any scaling up or down of the content is within the scope disclosed in the examples of this application. Specifically, the mass described in the description of the embodiments of this application may be mass units well known in the chemical industry such as μg, mg, g, kg, etc.

The terms "first" and "second" are only used for descriptive purposes to distinguish objects such as substances from each other, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. For example, without departing from the scope of the embodiments of the present application, the first XX may also be called the second XX, and similarly, the second XX may also be called the first XX. Therefore, features defined as "first" and "second" may explicitly or implicitly include one or more of these features.

In the first aspect, embodiments of the present application provide a flame retardant, containing the following components: graphene oxide, phosphoric acid, urea, guanidine phosphate, dicyandiamide and a water solvent; in the mixed solution of the flame retardant, the graphene oxide The concentration is 8~10mg/ml, the concentration of phosphoric acid is 56~84mg/ml, the concentration of urea is 34~86mg/ml, the concentration of guanidine phosphate is 22~65mg/ml, and the concentration of dicyandiamide is 25~75mg/ml .

A flame retardant in the embodiment of the present application introduces graphene oxide as the carbon source in the intumescent flame retardant. Graphene oxide can act as a barrier to the transmission of heat and materials during the combustion process, and it can compound the acid source ( Phosphoric acid, guanidine phosphate) and nitrogen source (urea, guanidine phosphate) synergistically exert a flame retardant effect, which is beneficial to improving the flame retardant performance and washability of cotton fabrics.

A second aspect of the embodiment of the present application provides a method for preparing a flame retardant, including the following steps: mixing graphene oxide solution, phosphoric acid, urea, guanidine phosphate and dicyandiamide to prepare a flame retardant;

In the mixed solution of the flame retardant, the concentration of graphene oxide is 8 to 10 mg/ml, the concentration of phosphoric acid is 56 to 84 mg/ml, the concentration of urea is 34 to 86 mg/ml, and the concentration of guanidine phosphate is 22 to 65 mg/ml. , the concentration of dicyandiamide is 25~75mg/ml.

In specific embodiments of the present application, the following steps can be used to prepare the flame retardant: adding graphene oxide (GO) solution, phosphoric acid (H ₃ PO ₄ ), urea (Urea), guanidine phosphate (GP) and The catalyst dicyandiamide (DICY) is prepared into a flame retardant mixed solution.

Among them, in the mixed solution, the concentration M1 of graphene oxide is 8-10 mg/ml, the concentration M2 of phosphoric acid is 56-84 mg/ml, the concentration M3 of urea is 34-86 mg/ml, and the concentration M4 of guanidine phosphate is 22-22 mg/ml. 65mg/ml, the concentration M5 of dicyandiamide is 25~75mg/ml.

The preparation method of the flame retardant in the embodiment of the present application is simple, the preparation cost is low, the preparation process is green and environmentally friendly, and it is easy to realize large-scale production.

The third aspect of the embodiment of the present application provides an application of the above-mentioned flame retardant on flame-retardant cotton fabrics.

The fourth aspect of the embodiment of the present application provides a washable flame-retardant cotton fabric. The surface of the flame-retardant cotton fabric contains a flame retardant. The flame retardant contains the following components: graphene oxide, phosphoric acid, urea, guanidine phosphate, bis- In the mixed solution of cyanamide and water solvent; flame retardant, the concentration of graphene oxide is 8~10mg/ml, the concentration of phosphoric acid is 56~84mg/ml, the concentration of urea is 34~86mg/ml, and the concentration of guanidine phosphate is The concentration of dicyandiamide is 22~65mg/ml, and the concentration of dicyandiamide is 25~75mg/ml.

The water-resistant flame-retardant cotton fabric in the embodiment of the present application is coated with a flame retardant containing graphene oxide, phosphoric acid, urea, guanidine phosphate and dicyandiamide on the surface of the cotton fabric, and the flame retardant is constructed during the high-temperature drying process. Covalent grafting with cotton fabric fiber molecules (P-O-C and C=N-C grafting), while self-assembly can occur between graphene oxide and cotton fiber molecules in the flame retardant system to prepare a "three-dimensional through-structure" "The washable flame-retardant cotton fabric simultaneously achieves the flame-retardant and washable properties of cotton fabrics.

The fifth aspect of the embodiments of the present application provides a method for preparing a washable flame-retardant cotton fabric, including the following steps:

(1) Pretreat the surface of cotton fabric;

(2) Prepare a flame retardant containing graphene oxide, phosphoric acid, urea, guanidine phosphate and dicyandiamide; in the mixed solution of the flame retardant, the concentration of graphene oxide is 8 to 10 mg/ml, and the concentration of phosphoric acid is 56 to 56 mg/ml. 84mg/ml, the concentration of urea is 34~86mg/ml, the concentration of guanidine phosphate is 22~65mg/ml, and the concentration of dicyandiamide is 25~75mg/ml;

(3) Impregnating or coating the surface of the pretreated cotton fabric with the flame retardant, and obtaining the flame retardant and antibacterial cotton fabric after drying treatment.

In the above step (2), the pretreatment process is as follows: soaking the cotton fabric in an alkaline solution, then washing it with water until it is neutral and drying it. In the embodiment of the present application, the alkaline solution is sodium hydroxide solution or potassium hydroxide solution. The concentration of the alkaline solution can be selected from 0.5 to 2mol/L.

In the above step (3), the temperature of the drying process is 150-170°C and the time is 6-10 minutes. The moisture on the surface of the fabric is removed through drying treatment, and high temperature drying is used to achieve P-O-C grafting and C=N-C grafting between the flame retardant and cotton fiber molecules. After drying, the surface of the cotton fabric can be repeatedly coated with flame retardant multiple times to achieve better flame retardant and washable effects. Specifically, during the coating process, a 250-mesh screen-assisted scraper coating technology can be used to evenly coat the new intumescent flame retardant prepared in step (1) on the front side of the cotton fabric pretreated in step (2). , and dried; then the reverse side is coated and the operation is repeated to obtain a double-sided coated flame-retardant cotton fabric. The self-assembly effect between GO in the flame retardant and cotton fabric fiber molecules is used to achieve the coating effect on cotton fibers. At the same time, the P-O-C grafting and C= between the flame retardant and cotton fiber molecules are achieved during the high-temperature drying process. After N-C grafting, a flame-retardant cotton fabric is finally obtained (the combination between the flame retardant and the cotton fabric fiber molecules is shown in Figure 1).

The preparation method of a washable flame-retardant cotton fabric in the embodiment of the present application uses a new intumescent flame retardant to reactively modify the hydroxyl functional groups on the surface of the cotton fabric. The flame retardant molecules not only interact with the cotton fibers on both sides of the cotton fabric The molecules are combined in the form of multiple bonds, and the flame retardant penetrates into the woven structure of the cotton fabric, forming a washable flame-retardant cotton fabric with a "three-dimensional penetration structure". The dense "three-dimensional penetrating structure" provides excellent combustion protection for the cotton fabric base; the prepared water-resistant flame-retardant cotton fabric exhibits good water-wash resistance.

The preparation method of the washable flame-retardant cotton fabric in the embodiment of the present application is simple, the preparation cost is low, the preparation process is green and environmentally friendly, and it is easy to realize large-scale production.

The following uses multiple specific examples to illustrate a flame retardant, washable flame retardant cotton fabric, preparation method and application of the embodiments of the present application.

Example 1

Embodiment 1 of the present application provides a flame retardant, water-resistant flame-retardant cotton fabric and a preparation method thereof, which includes the following steps:

(1) Pretreatment of cotton fabrics to activate hydroxyl groups on cotton fibers

Prepare a 1 mol/L NaOH solution, soak the cotton fabric in the solution for 24 hours, then rinse it with deionized water several times until the surface of the cotton fabric is nearly neutral, and dry it at 80°C for later use.

(2) Preparation of flame retardant

Add 15 mg/ml graphene oxide (GO) solution, phosphoric acid (H ₃ PO ₄ ), urea (Urea), guanidine phosphate (GP) and catalyst dicyandiamide (DICY) to the water solvent to prepare a flame retardant mixture solution. In the mixed solution, the concentration of graphene oxide is 8mg/ml, the concentration of phosphoric acid is 84mg/ml, the concentration of urea is 77mg/ml, the concentration of guanidine phosphate is 65mg/ml, and the concentration of dicyandiamide is 50mg/ml, room temperature (25℃) stirring reaction for 12h to obtain the flame retardant.

(3) Preparation of washable flame-retardant cotton fabric

Using 250-mesh screen-assisted scraper coating technology, the new intumescent flame retardant prepared in step (2) is evenly coated on the front of the cotton fabric pretreated in step (1), and dried at a temperature of 170°C for 5 minutes. ; Then coat the reverse side and repeat the operation 6 times to obtain a washable flame-retardant cotton fabric with a "three-dimensional penetration structure".

Example 2

Embodiment 2 of the present application provides a flame retardant, water-resistant flame-retardant cotton fabric and a preparation method thereof, which includes the following steps:

(1) Pretreatment of cotton fabrics to activate hydroxyl groups on cotton fibers

Prepare a 1 mol/L NaOH solution, soak the cotton fabric in the solution for 24 hours, then rinse it with deionized water several times until the surface of the cotton fabric is nearly neutral, and dry it at 80°C for later use.

(2) Preparation of flame retardant

Add 15 mg/ml graphene oxide (GO) solution, phosphoric acid (H ₃ PO ₄ ), urea (Urea), guanidine phosphate (GP) and catalyst dicyandiamide (DICY) to the water solvent to prepare a flame retardant mixture solution. In the mixed solution, the concentration of graphene oxide is 8mg/ml, the concentration of phosphoric acid is 84mg/ml, the concentration of urea is 86mg/ml, the concentration of guanidine phosphate is 65mg/ml, and the concentration of dicyandiamide is 75mg/ml, room temperature (25℃) stirring reaction for 12h to obtain the flame retardant.

(3) Preparation of washable flame-retardant cotton fabric

Using the 250-mesh screen-assisted scraper coating technology, the new intumescent flame retardant prepared in step (2) is evenly coated on the front of the cotton fabric pretreated in step (1), and dried at a temperature of 150°C for 5 minutes. ; Then coat the reverse side and repeat the operation 6 times to obtain a washable flame-retardant cotton fabric with a "three-dimensional penetration structure".

Example 3

Embodiment 3 of the present application provides a flame retardant, water-resistant flame-retardant cotton fabric and a preparation method thereof, which includes the following steps:

(1) Pretreatment of cotton fabrics to activate hydroxyl groups on cotton fibers

Prepare a 1 mol/L NaOH solution, soak the cotton fabric in the solution for 24 hours, then rinse it with deionized water several times until the surface of the cotton fabric is nearly neutral, and dry it at 80°C for later use.

(2) Preparation of flame retardant

Add 15 mg/ml graphene oxide (GO) solution, phosphoric acid (H ₃ PO ₄ ), urea (Urea), guanidine phosphate (GP) and catalyst dicyandiamide (DICY) to the water solvent to prepare a flame retardant mixture solution. In the mixed solution, the concentration of graphene oxide is 8mg/ml, the concentration of phosphoric acid is 84mg/ml, the concentration of urea is 34mg/ml, the concentration of guanidine phosphate is 65mg/ml, and the concentration of dicyandiamide is 75mg/ml, room temperature (25℃) stirring reaction for 12h to obtain the flame retardant.

(3) Preparation of washable flame-retardant cotton fabric

Using 250-mesh screen-assisted scraper coating technology, the new intumescent flame retardant prepared in step (2) is evenly coated on the front of the cotton fabric pretreated in step (1), and dried at a temperature of 170°C for 5 minutes. ; Then coat the reverse side and repeat the operation 6 times to obtain a washable flame-retardant cotton fabric with a "three-dimensional penetration structure".

Example 4

Embodiment 4 of the present application provides a flame retardant, water-resistant flame-retardant cotton fabric and a preparation method thereof, which includes the following steps:

(1) Pretreatment of cotton fabrics to activate hydroxyl groups on cotton fibers

Prepare a 1 mol/L NaOH solution, soak the cotton fabric in the solution for 24 hours, then rinse it with deionized water several times until the surface of the cotton fabric is nearly neutral, and dry it at 80°C for later use.

(2) Preparation of flame retardant

Add 15 mg/ml graphene oxide (GO) solution, phosphoric acid (H ₃ PO ₄ ), urea (Urea), guanidine phosphate (GP) and catalyst dicyandiamide (DICY) to the water solvent to prepare a flame retardant mixture solution. In the mixed solution, the concentration of graphene oxide is 8mg/ml, the concentration of phosphoric acid is 84mg/ml, the concentration of urea is 51mg/ml, the concentration of guanidine phosphate is 22mg/ml, and the concentration of dicyandiamide is 50mg/ml, room temperature (25℃) stirring reaction for 12h to obtain the flame retardant.

(3) Preparation of washable flame-retardant cotton fabric

Using 250-mesh screen-assisted scraper coating technology, the new intumescent flame retardant prepared in step (2) is evenly coated on the front of the cotton fabric pretreated in step (1), and dried at a temperature of 170°C for 5 minutes. ; Then coat the reverse side and repeat the operation 6 times to obtain a washable flame-retardant cotton fabric with a "three-dimensional penetration structure".

Example 5

Embodiment 5 of the present application provides a flame retardant, water-resistant flame-retardant cotton fabric and a preparation method thereof, which includes the following steps:

(1) Pretreatment of cotton fabrics to activate hydroxyl groups on cotton fibers

Prepare a 1 mol/L NaOH solution, soak the cotton fabric in the solution for 24 hours, then rinse it with deionized water several times until the surface of the cotton fabric is nearly neutral, and dry it at 80°C for later use.

(2) Preparation of flame retardant

Add 15 mg/ml graphene oxide (GO) solution, phosphoric acid (H ₃ PO ₄ ), urea (Urea), guanidine phosphate (GP) and catalyst dicyandiamide (DICY) to the water solvent to prepare a flame retardant mixture solution. In the mixed solution, the concentration of graphene oxide is 8mg/ml, the concentration of phosphoric acid is 84mg/ml, the concentration of urea is 77mg/ml, the concentration of guanidine phosphate is 65mg/ml, and the concentration of dicyandiamide is 25mg/ml, room temperature (25℃) stirring reaction for 12h to obtain the flame retardant.

(3) Preparation of washable flame-retardant cotton fabric

Using 250-mesh screen-assisted scraper coating technology, the new intumescent flame retardant prepared in step (2) is evenly coated on the front of the cotton fabric pretreated in step (1), and dried at a temperature of 170°C for 5 minutes. ; Then coat the reverse side and repeat the operation 6 times to obtain a washable flame-retardant cotton fabric with a "three-dimensional penetration structure".

Example 6

Embodiment 6 of the present application provides a flame retardant, water-resistant flame-retardant cotton fabric and a preparation method thereof, which includes the following steps:

(1) Pretreatment of cotton fabrics to activate hydroxyl groups on cotton fibers

Prepare a 1 mol/L NaOH solution, soak the cotton fabric in the solution for 24 hours, then rinse it with deionized water several times until the surface of the cotton fabric is nearly neutral, and dry it at 80°C for later use.

(2) Preparation of flame retardant

Add 15 mg/ml graphene oxide (GO) solution, phosphoric acid (H ₃ PO ₄ ), urea (Urea), guanidine phosphate (GP) and catalyst dicyandiamide (DICY) to the water solvent to prepare a flame retardant mixture solution. In the mixed solution, the concentration of graphene oxide is 8mg/ml, the concentration of phosphoric acid is 84mg/ml, the concentration of urea is 77mg/ml, the concentration of guanidine phosphate is 65mg/ml, and the concentration of dicyandiamide is 75mg/ml, room temperature (25℃) stirring reaction for 12h to obtain the flame retardant.

(3) Preparation of washable flame-retardant cotton fabric

Using the 250-mesh screen-assisted scraper coating technology, the new intumescent flame retardant prepared in step (2) is evenly coated on the front of the cotton fabric pretreated in step (1), and dried at a temperature of 150°C for 5 minutes. ; Then coat the reverse side and repeat the operation 6 times to obtain a washable flame-retardant cotton fabric with a "three-dimensional penetration structure".

Example 7

Embodiment 7 of the present application provides a flame retardant, water-resistant flame-retardant cotton fabric and a preparation method thereof, which includes the following steps:

(1) Pretreatment of cotton fabrics to activate hydroxyl groups on cotton fibers

Prepare a 1 mol/L NaOH solution, soak the cotton fabric in the solution for 24 hours, then rinse it with deionized water several times until the surface of the cotton fabric is nearly neutral, and dry it at 80°C for later use.

(2) Preparation of flame retardants

Add 15 mg/ml graphene oxide (GO) solution, phosphoric acid (H ₃ PO ₄ ), urea (Urea), guanidine phosphate (GP) and catalyst dicyandiamide (DICY) to the water solvent to prepare a flame retardant mixture solution. In the mixed solution, the concentration of graphene oxide is 8mg/ml, the concentration of phosphoric acid is 56mg/ml, the concentration of urea is 51mg/ml, the concentration of guanidine phosphate is 43mg/ml, and the concentration of dicyandiamide is 50mg/ml, room temperature (25℃) stirring reaction for 12h to obtain the flame retardant.

(3) Preparation of washable flame-retardant cotton fabric

Using 250-mesh screen-assisted scraper coating technology, the new intumescent flame retardant prepared in step (2) is evenly coated on the front of the cotton fabric pretreated in step (1), and dried at a temperature of 170°C for 5 minutes. ; Then coat the reverse side and repeat the operation 6 times to obtain a washable flame-retardant cotton fabric with a "three-dimensional penetration structure".

Example 8

Embodiment 8 of the present application provides a flame retardant, water-resistant flame-retardant cotton fabric and a preparation method thereof, which includes the following steps:

(1) Pretreatment of cotton fabrics to activate hydroxyl groups on cotton fibers

Prepare a 1 mol/L NaOH solution, soak the cotton fabric in the solution for 24 hours, then rinse it with deionized water several times until the surface of the cotton fabric is nearly neutral, and dry it at 80°C for later use.

(2) Preparation of flame retardants

Add 15 mg/ml graphene oxide (GO) solution, phosphoric acid (H ₃ PO ₄ ), urea (Urea), guanidine phosphate (GP) and catalyst dicyandiamide (DICY) to the water solvent to prepare a flame retardant mixture solution. In the mixed solution, the concentration of graphene oxide is 8mg/ml, the concentration of phosphoric acid is 84mg/ml, the concentration of urea is 51mg/ml, the concentration of guanidine phosphate is 43mg/ml, and the concentration of dicyandiamide is 50mg/ml, room temperature (25℃) stirring reaction for 12h to obtain the flame retardant.

(3) Preparation of washable flame-retardant cotton fabric

Using 250-mesh screen-assisted scraper coating technology, the new intumescent flame retardant prepared in step (2) is evenly coated on the front of the cotton fabric pretreated in step (1), and dried at a temperature of 170°C for 5 minutes. ; Then coat the reverse side and repeat the operation 6 times to obtain a washable flame-retardant cotton fabric with a "three-dimensional penetration structure".

A burning experiment was conducted on the washable flame-retardant cotton fabric prepared in Example 3 of the present application. The SEM morphology before (e) (f) and after (g) (h) burning is shown in Figure 2. By comparing the SEM photos of the flame-retardant cotton fabric before and after burning, it can be clearly seen that the woven structure of the flame-retardant cotton fabric remains very complete and dense after burning. The small bubble-like balls appearing in Figure (h) further illustrate the expansion type. The flame retardant has played a flame retardant role. Comparison of the photos before and after burning shows that the water-resistant flame-retardant cotton fabric prepared in the embodiment of the present application has very good flame retardant properties.

The flame-retardant cotton fabrics prepared in Examples 1 to 8 of the present application were tested for limiting oxygen index (LOI: %) and water-washing resistance. The results are as follows. Among them, the test conditions are as follows:

Limiting oxygen index test: According to the standard GB/T5454-1997 "Determination of Combustion Performance of Textiles-Oxygen Index Method", the sample is placed under vertical test conditions and the minimum oxygen concentration that just maintains combustion in the oxygen and nitrogen mixed air flow (also called limiting oxygen index) test method. Clamp the sample on the sample clamp and place it vertically in the combustion tube. In the upward flowing oxygen and nitrogen gas flow, ignite the upper end of the sample, observe its combustion characteristics, and compare its afterburning time with the specified limit value (not more than 2 minutes) Or the damaged length (not exceeding 40mm). By testing a series of samples in different oxygen concentrations, the minimum oxygen concentration value expressed as the percentage of oxygen during combustion can be measured.

Washing resistance test: Use a magnetic stirrer and beaker to complete the washing resistance test. Add 500ml of water to a 500ml beaker, cut the prepared flame-retardant cotton fabric into 5cm×12cm, place it in the beaker, stir and wash with water. Set the magnetic stirrer speed to 600r/min, and 10 minutes is one water wash.

According to the test results in the above table, it can be seen that the LOI of the flame-retardant cotton fabrics prepared in Examples 1 to 8 is much higher than that of pure cotton fabrics when not washed, which shows that the flame-retardant cotton fabrics prepared in Examples of the present application have very good Excellent flame retardant properties, after 50 times of washing, the LOI of the flame retardant cotton fabrics prepared in Examples 1 to 8 is greater than 18% of pure cotton. Among them, the LOI of the flame-retardant cotton fabrics prepared in Example 1, Example 2, Example 5, and Example 6 were 32.8%, 28%, 27.5%, and 27.1% respectively, all greater than 27% (reaching the standard for flame-retardant textiles). , that is, LOI>26%), which shows that the flame-retardant cotton fabric prepared in the embodiment of the present application has good water-washing resistance.

The above embodiments only express several implementation modes of the present application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the patent scope of the present application. It should be noted that, for those of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all fall within the protection scope of the present application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims (4)

1. A method for preparing washable flame-retardant cotton fabric, which is characterized by comprising the following steps: The surface of the cotton fabric is pretreated; the pretreatment process is as follows: soaking the cotton fabric in an alkaline solution, then washing it with water until it becomes neutral and drying it; Prepare a flame retardant containing graphene oxide solution, phosphoric acid, urea, guanidine phosphate and dicyandiamide; in the flame retardant, the concentration of the graphene oxide is 8~10 mg/ml, and the concentration of the phosphoric acid is 56~84 mg/ml, the concentration of urea is 34~86 mg/ml, the concentration of guanidine phosphate is 22~65 mg/ml, and the concentration of dicyandiamide is 25~75 mg/ml; The flame retardant is impregnated or coated on the surface of the pre-treated cotton fabric, and a washable flame-retardant cotton fabric is obtained after drying treatment; the temperature of the drying treatment is 150~170°C and the time is 5 min. 2. The preparation method of a washable flame-retardant cotton fabric according to claim 1, wherein the alkaline solution is a sodium hydroxide solution or a potassium hydroxide solution. 3. The preparation method of a washable flame-retardant cotton fabric as claimed in claim 2, wherein the concentration of the alkaline solution is 0.5~2 mol/L. 4. A washable flame-retardant cotton fabric, characterized in that it is prepared by the preparation method described in any one of claims 1-3.