A functional polyether sulfone fiber and a preparation method and application thereof

Abstract

The present application belongs to the field of textile, and relates to the preparation of functional fiber, in particular to a kind of functional polyether sulfone fiber and its preparation method and application.The present application uses polyether sulfone as raw material, forms polyether sulfone solution by selecting suitable solvent, then adds functional ionic liquid or functional material in polyether sulfone solution, finally forms polyether sulfone-ionic liquid-functional material mixed system.Because polyether sulfone, ionic liquid and added functional particles are compatible, in the dissolving process, due to the shear, stretching and other effects applied by continuous phase, after stirring uniformly and defoaming, at room temperature, through melting or electrospinning forming, the formed fiber is placed in atmospheric environment or deionized water to remove ionic liquid and other additives, and the fiber after removing ionic liquid and additives is dried.If the fiber is spun by melting method, the spinning temperature can be significantly reduced, the energy consumption is reduced, and the cost is saved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of textiles, and relates to the preparation of functional fibers, in particular to a functional polyether sulfone fiber and a preparation method and application thereof. BACKGROUND

[0002] Polyether sulfone (PES) has thermal chemical stability, good mechanical strength, light weight, large specific surface area, high dimensional stability, acid and alkali resistance, blood compatibility, excellent flame retardancy, good internal pore connectivity and other advantages. Therefore, polyether sulfone (PES) is one of the most widely used separation membrane materials. As a material of polysulfone, polyether sulfone (PES) has good mechanical properties and has been widely used, but due to its hydrophobic structure, it is easy to be contaminated after film formation. Membrane pollution is mainly caused by the adsorption of non-polar solutes, hydrophobic particles or bacteria. This is a problem that is concerned in membrane filtration. Once the filter membrane is contaminated, it will lead to higher energy consumption of the membrane, shorter service life of the membrane, and difficult to achieve separation performance. In view of the advantages and disadvantages of PES membrane, the current research trend of PES is to develop new membrane materials and structures, especially to reduce the influence of pollution, biocompatibility and functionality.

[0003] There are generally three ways to modify PES membranes: one is to modify the surface of the prepared PES membrane, the surface modification of PES membrane is a more common method, through modification, the hydrophobicity of the PES membrane surface can be changed, so as to introduce hydrophilic performance groups or particles while keeping the membrane skeleton unchanged. The hydrophilicity of the modified PES membrane can be determined by water contact angle. Two is to modify the chemical structure of PES material, and then prepare modified membrane. Bulk modification refers to introducing functional groups into the main chain of polymer macromolecules, such as sulfonic acid group (-SO3 -hydrophilic groups, such as hydroxyl (-OH), carboxyl (-COOH), amino (-NH2) or a combination thereof. The introduction of hydrophilic groups improves the hydrophilicity of PES. Three is blending, which can also be considered as surface modification. Blending of hydrophilic functional groups with PES membranes is considered to be one of the simplest methods to improve the hydrophilicity of the membrane surface. Polymer blending is to directly blend hydrophobic PES membranes with hydrophilic polymers. After blending of the hydrophilic polymer with PES, the performance of the PES membrane will usually be changed. The hydrophilicity of the membrane is improved. However, the elution of the mixed hydrophilic polymer is inevitable. Therefore, the amphiphilic copolymer synthesized recently is used for blending with PES to prepare membranes. This modification method can find a balance point between hydrophobicity and hydrophilicity. The addition of hydrophilic materials in the pores of the membrane has a positive effect on the reduction of flux and antifouling performance, and endows the membrane with good reactivity and other functions. Patent CN1763278A discloses a method for preparing polyether sulfone fibers, which directly melts and spins polyether sulfone to prepare, and does not have other functions, and the melting heating degree used is high, and the technology required is high; it can be seen that the existing polyether sulfone fiber (fiber membrane) technology has good treatment effect, but the technical requirement is high, the investment is large, and the treatment cost is high. SUMMARY

[0004] To solve the above technical problems, the present application provides a functional polyether sulfone fiber and a preparation method and application thereof.

[0005] The technical scheme of the present application is as follows:

[0006] A preparation method of a functional polyether sulfone fiber, comprising the following steps:

[0007] (1) preparing a polyether sulfone solution, adding ionic liquid and functional particles under stirring to obtain a spinning solution;

[0008] (2) spinning the spinning solution of step (1) after vacuum degassing, and drying after water washing to obtain the functional polyether sulfone fiber.

[0009] The solvent of the polyether sulfone solution in step (1) is DMF, 1-allyl-3-methyl imidazole chloride or DMSO.

[0010] The mass concentration of the polyether sulfone solution is 10-20%.

[0011] The ionic liquid is 1-allyl-3-methyl imidazole hexafluorophosphate.

[0012] The functional particles are one or more of graphene oxide, graphene powder, reduced graphene oxide, graphene suspension nano silver ion, nano TiO2 and magnetic nano Fe3O4.

[0013] The mass ratio of polyether sulfone, ionic liquid and functional particles in the spinning solution is 83:10:7.

[0014] The spinning in the above step (2) is any one of electrospinning, wet spinning and melt spinning.

[0015] The parameters of the electrospinning are: voltage 16-24 kv, flow rate 0.3-0.8 ml / h, spinning distance 7-12 cm; the parameters of the wet spinning are: viscosity 50-80 mPa·s, coagulation bath concentration 20-80%; the parameters of the melt spinning are: temperature 180-230 ℃, winding speed 170-250 m / min.

[0016] The coagulation bath used in the spinning process is any one of the following: ionic liquid aqueous solution, the mass fraction of ionic liquid in the coagulation bath solution is 1-10%, the coagulation bath temperature is 20-50 ℃; ethanol aqueous solution, the mass fraction of anhydrous ethanol in the coagulation bath solution is 1-25%, the coagulation bath temperature is 10-45 ℃; air coagulation, the temperature is room temperature to 100 ℃.

[0017] The functional polyether sulfone fiber prepared by the above method.

[0018] The application of the functional polyether sulfone fiber in preparing flame-retardant materials, conductive materials, photocatalytic degradation of dyes and carbon fiber composite materials.

[0019] The present application has the following advantages:

[0020] 1. The present application uses polyether sulfone as raw material, forms a polyether sulfone solution by selecting a suitable solvent, then adds a functional ionic liquid or a functional material in the polyether sulfone solution, and finally forms a polyether sulfone-ionic liquid-functional material mixed system. Since polyether sulfone, ionic liquid and the added functional particles are compatible, in the dissolving process, they are subjected to shearing, stretching and other actions exerted by the continuous phase; after uniform stirring and degassing, the fiber after forming is placed in an atmospheric environment or deionized water to remove the ionic liquid and other additives, and the fiber after removing the ionic liquid and the additives is dried. If the fiber is spun by the melt method, the spinning temperature of polyether sulfone (high-temperature spinning above 300 ℃) is reduced to about 200 ℃, special spinning equipment is not needed, the equipment cost and energy consumption are reduced, the spinning temperature can be significantly reduced, the energy consumption is reduced, and the cost is saved.

[0021] 2. Compared with other methods for preparing functional fibers, the method of the present application can be used to manufacture functional fibers by using conventional industrialized spinning equipment, thereby reducing the investment cost. The present application has the advantages of low spinning temperature, continuous production and high yield. It can provide a simple process route for the future realization of the toughening and flow guiding applications of polyether sulfone in carbon fiber composite materials.

[0022] 3. The application is to use polyether sulfone as raw material, the added functional particles have good compatibility and high efficiency, meet the requirements of economy and environmental protection. The prepared polyether sulfone has wide application prospects in flame-retardant materials, conductive materials, photocatalytic degradation of dyes, and preparation of carbon fiber composite materials. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0024] Figure 1 The electrospun polyether sulfone flame-retardant fiber film prepared for Example 1.

[0025] Figure 2 The graph of the change of photocatalytic and adsorption properties of the electrospun PES fiber film with time.

[0026] Figure 3 The polyether sulfone fiber prepared by melt spinning for Example 9. DETAILED DESCRIPTION

[0027] The technical solutions of the present application will be described below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0028] A method for preparing a functional polyether sulfone fiber, comprising the following steps:

[0029] (1) preparing a polyether sulfone solution, adding ionic liquid and functional particles under stirring to obtain a spinning solution;

[0030] (2) the spinning solution of step (1) is vacuum degassed and then spun, and after water washing and drying, the functional polyether sulfone fiber is obtained.

[0031] The solvent of the polyether sulfone solution in step (1) above is DMF, 1-allyl-3-methyl imidazole chloride or DMSO.

[0032] The mass concentration of the above polyether sulfone solution is 10-20%.

[0033] The ionic liquid is 1-allyl-3-methyl imidazole hexafluorophosphate.

[0034] The functional particles are one or more of graphene oxide, graphene powder, reduced graphene oxide, graphene suspension nano silver ions, nano TiO2 and magnetic nano Fe3O4.

[0035] The mass ratio of polyether sulfone, ionic liquid and functional particles in the spinning solution is 83:10:7.

[0036] The spinning in step (2) is any one of electrospinning, wet spinning and melt spinning.

[0037] The parameters of the electrospinning are: voltage 16-24kv, flow rate 0.3-0.8ml / h, spinning distance 7-12cm; the parameters of the wet spinning are: viscosity 50-80mPa·s, coagulation bath concentration 20-80%; the parameters of the melt spinning are: temperature 180-230℃, winding speed 170-250m / min.

[0038] The coagulation bath used in the spinning process is selected from any one of the following schemes: ionic liquid aqueous solution, the mass fraction of ionic liquid in the coagulation bath solution is 1-10%, the coagulation bath temperature is 20-50℃; ethanol aqueous solution, the mass fraction of anhydrous ethanol in the coagulation bath solution is 1-25%, the coagulation bath temperature is 10-45℃; air coagulation, the temperature is room temperature to 100℃.

[0039] The following will be described in conjunction with specific examples:

[0040] Example 1

[0041] The preparation method of the functional polyether sulfone fiber of the present embodiment comprises the following steps:

[0042] (1) The oven-dried polyether sulfone powder is dissolved in DMF, and under the action of mechanical stirring, it is dissolved at room temperature for 30min to obtain a polyether sulfone solution with a concentration of 15%. Then 1-allyl-3-methylimidazolium hexafluorophosphate and reduced graphene oxide are added, and after sufficient stirring, a spinning solution is obtained. The mass of polyether sulfone, 1-allyl-3-methylimidazolium hexafluorophosphate and reduced graphene oxide in the spinning solution is 8.3g, 1.0g and 7.0g respectively.

[0043] (2) The spinning solution is degassed in a vacuum oven, electrospun (voltage 20kv, flow rate 0.5ml / h, spinning distance 10cm), and the DMF is volatilized in air. The excess ionic liquid is removed by washing with water for 3 times, and then the modified polyether sulfone flame-retardant fiber is obtained after drying. The electron microscope image is shown in Figure 1 .

[0044] The fiber is tested by a limiting oxygen index instrument, and the LOI of the fiber is 26.5%.

[0045] Example 2

[0046] The preparation method of the functional polyether sulfone fiber of the embodiment is as follows:

[0047] (1) The polyether sulfone powder dried to absolute dryness is dissolved in 1-allyl-3-methylimidazole chloride, and dissolved at 100°C for 1 h under the action of mechanical stirring to obtain a polyether sulfone solution with a concentration of 20%; 1% of graphene oxide and 5% of nano silver ions are added, and the spinning solution is obtained after sufficient stirring; the mass of polyether sulfone, 1-allyl-3-methylimidazole hexafluorophosphate and 1% of graphene oxide and 5% of nano silver ions in the spinning solution is 8.3 g, 1.0 g and 7.0 g respectively.

[0048] (2) The spinning solution is filtered, vacuum oven defoamed, and wet spun (the optimal viscosity of the spinning solution is 75.24 mPa·s), and the spinning solution is used as a coagulation bath with 20% of ethanol aqueous solution as the coagulation bath, and the coagulation bath temperature is 10-45°C; after solidification, the modified polyether sulfone conductive fiber is obtained after being taken out, washed with water for three times and dried.

[0049] After detection:

[0050] The fiber conductivity is 1.4 x 10 -3 S / cm, the dry strength is 3.3 CN / dtex, the wet strength is 3.0 CN / dtex, and the dry elongation is 9%, which is increased by 61% compared with that before modification.

[0051] Example 3

[0052] The preparation method of the functional polyether sulfone fiber of the embodiment is as follows:

[0053] (1) The polyether sulfone powder dried to absolute dryness is dissolved in DMSO, and dissolved at room temperature for 30 min under the action of mechanical stirring to obtain a polyether sulfone solution with a solubility of 10%; 1-allyl-3-methylimidazole hexafluorophosphate, 10% of nano TiO2 and 5% of magnetic nano Fe3O4 are added, and the spinning solution is obtained after sufficient stirring; the mass of polyether sulfone, 1-allyl-3-methylimidazole hexafluorophosphate, nano TiO2 and magnetic nano Fe3O4 in the spinning solution is 83 g, 10 g, 7 g respectively.

[0054] (2) The spinning solution is filtered, vacuum oven defoamed, and electrospun (voltage 20 kv, flow rate 0.5 ml / h, spinning distance 10 cm), and the modified polyether sulfone fiber with photocatalytic and adsorption properties is obtained after being taken out after air drying and solidification, and dried after being washed with water for three times.

[0055] Under the irradiation of an ultraviolet light source, the adsorption and catalytic properties of dyes at different times are as follows: Figure 2As shown in Figure 2 It can be seen that the PES fiber with a mass ratio of 2:1 has better and better effect with the increase of time, and the permeability of the waste liquid increases more and more, and the permeability is 98%, indicating that the dye in the waste liquid is almost completely catalyzed.

[0056] Example 4

[0057] The preparation method of the functional polyether sulfone fiber of the embodiment is as follows:

[0058] (1) The oven-dried polyether sulfone powder is dissolved in 1-allyl-3-methyl imidazole chloride, and under the action of mechanical stirring, it is dissolved at 100°C for 1h to obtain a polyether sulfone solution with a concentration of 15%; 1% of graphene oxide and 5% of nano silver ions are added, and after sufficient stirring, a spinning solution is obtained; the mass of polyether sulfone, 1-allyl-3-methyl imidazole hexafluorophosphate, 1% of graphene oxide and 5% of nano silver ions in the spinning solution is 8.3g, 1.0g, 7.0g respectively

[0059] (2) The spinning solution is filtered, vacuum oven degassing, wet spinning (the optimal viscosity of the spinning solution is 50mPa·s), and 20% of ethanol aqueous solution is used as the coagulation bath, the coagulation bath temperature is 10-45°C, after solidification, it is taken out, washed with water for 3 times and dried to obtain the modified polyether sulfone conductive fiber. The heat stretching multiple of the polyether sulfone primary fiber is 15, which has the best tensile strength.

[0060] After detection:

[0061] The fiber conductivity is 1.38×10 -3 S / cm, dry strength is 3.1CN / dtex, wet strength is 2.8CN / dtex, dry stretch is 8.5%, which is improved by 60.8% compared with before modification.

[0062] Example 5

[0063] The preparation method of the functional polyether sulfone fiber of the embodiment is as follows:

[0064] (1) The oven-dried polyether sulfone powder is dissolved in 1-allyl-3-methyl imidazole chloride, and under the action of mechanical stirring, it is dissolved at 100°C for 1h to obtain a polyether sulfone solution with a concentration of 15%; 1% of graphene oxide and 5% of nano silver ions are added, and after sufficient stirring, a spinning solution is obtained; the mass of polyether sulfone, 1-allyl-3-methyl imidazole hexafluorophosphate, 1% of graphene oxide and 5% of nano silver ions in the spinning solution is 8.3g, 1.0g, 7.0g respectively

[0065] (2) The spinning solution is filtered, vacuum oven defoaming, wet spinning (the optimal viscosity of the spinning solution is 50 mPa·s), and 20% ethanol aqueous solution is used as the coagulation bath, the coagulation bath temperature is 10-45℃, and the modified polyether sulfone conductive fiber is obtained after solidification, three water washing and air drying.

[0066] After detection:

[0067] The fiber conductivity is 1.38 x 10 -3 S / cm, dry strength is 3.1 CN / dtex, wet strength is 2.8 CN / dtex, dry stretch is 8.5%, which is increased by 60.8% compared with before modification.

[0068] Example 6

[0069] The preparation method of the functional polyether sulfone fiber of the embodiment is as follows:

[0070] (1) The polyether sulfone powder dried to absolute dryness is dissolved in 1-allyl-3-methylimidazole chloride, and under the action of mechanical stirring, the dissolution is carried out at 100℃ for 1h to obtain a polyether sulfone solution with a concentration of 15%; 1% graphene oxide and 5% nano silver ions are added, and after sufficient stirring, a spinning solution is obtained; the mass of polyether sulfone, 1-allyl-3-methylimidazole hexafluorophosphate and 1% graphene oxide and 5% nano silver ions in the spinning solution is 8.3g, 1.0g and 7.0g respectively.

[0071] (2) The spinning solution is filtered, vacuum oven defoaming, wet spinning (the optimal viscosity of the spinning solution is 80 mPa·s), and 80% ethanol aqueous solution is used as the coagulation bath, the coagulation bath temperature is 10-45℃, and the modified polyether sulfone conductive fiber is obtained after solidification, three water washing and air drying. The heat stretching multiple of the polyether sulfone as-spun fiber is 13, which has the best tensile strength.

[0072] Example 7

[0073] The preparation method of the functional polyether sulfone fiber of the embodiment is as follows:

[0074] (1) The polyether sulfone powder dried to absolute dryness is dissolved in DMF, and under the action of mechanical stirring, the dissolution is carried out at room temperature for 30min to obtain a polyether sulfone solution with a concentration of 15%; 1-allyl-3-methylimidazole hexafluorophosphate and reduced graphene oxide are added, and after sufficient stirring, a spinning solution is obtained; the mass of polyether sulfone, 1-allyl-3-methylimidazole hexafluorophosphate and reduced graphene oxide in the spinning solution is 8.3g, 1.0g and 7.0g respectively.

[0075] (2) The spinning solution is degassed by vacuum oven, electrospun (voltage 16kv, flow rate 0.3ml / h, spinning distance 7cm), DMF is volatilized by air, and the excess ionic liquid is removed by three water washing, and the modified polyether sulfone flame-retardant fiber is obtained after drying.

[0076] The fiber filament LOI is 26.4% by the limiting oxygen index instrument test.

[0077] Example 8

[0078] The preparation method of the functional polyether sulfone fiber of the embodiment is as follows:

[0079] (1) The oven-dried polyether sulfone powder is dissolved in 1-allyl-3-methylimidazole chloride salt F under the action of mechanical stirring for 30min at room temperature to obtain a polyether sulfone solution with a concentration of 15%, 1-allyl-3-methylimidazole hexafluorophosphate and reduced graphene oxide are added, and the spinning solution is obtained after sufficient stirring; the mass of polyether sulfone, 1-allyl-3-methylimidazole hexafluorophosphate and reduced graphene oxide in the spinning solution is 8.3g, 1.0g and 7.0g respectively.

[0080] (2) The spinning solution is degassed by vacuum oven, electrospun (voltage 24kv, flow rate 0.8ml / h, spinning distance 12cm), DMF is volatilized by air, and the excess ionic liquid is removed by three water washing, and the modified polyether sulfone flame-retardant fiber is obtained after drying.

[0081] The fiber filament LOI is 27.4% by the limiting oxygen index instrument test.

[0082] Example 9

[0083] The preparation method of the functional polyether sulfone fiber of the embodiment is as follows:

[0084] (1) The oven-dried polyether sulfone powder is dissolved in 1-allyl-3-methylimidazole chloride salt F under the action of mechanical stirring for 30min at room temperature to obtain a polyether sulfone solution with a concentration of 15%, 1-allyl-3-methylimidazole hexafluorophosphate and reduced graphene oxide are added, and the spinning solution is obtained after sufficient stirring; the mass of polyether sulfone, 1-allyl-3-methylimidazole hexafluorophosphate and reduced graphene oxide in the spinning solution is 8.3g, 1.0g and 7.0g respectively.

[0085] (2) The spinning solution is degassed by vacuum oven, electrospun (voltage 24kv, flow rate 0.8ml / h, spinning distance 12cm), DMF is volatilized by air, and the excess ionic liquid is removed by three water washing, and the modified polyether sulfone flame-retardant fiber is obtained after drying.

[0086] The fiber filament LOI: 27.4% was detected by limiting oxygen index instrument test.

[0087] Example 10

[0088] The preparation method of the functional polyether sulfone fiber of the embodiment is as follows:

[0089] (1) The polyether sulfone powder dried to absolute dryness was dissolved in DMSO, and dissolved at room temperature for 30 minutes under the action of mechanical stirring to obtain a polyether sulfone solution with a solubility of 10%; 1-allyl-3-methylimidazole hexafluorophosphate and 10% nano-TiO2 were added, and the spinning solution was obtained after sufficient stirring; the mass of polyether sulfone, 1-allyl-3-methylimidazole hexafluorophosphate and nano-TiO2 in the spinning solution was 4.15 g, 0.5 g and 0.35 g respectively.

[0090] (2) The spinning solution was filtered, vacuum oven defoamed, melt spun (temperature 180°C, winding speed 170 meters / minute), and then taken out after air drying and solidification, and then dried after being washed with water for 3 times to obtain the functional polyether sulfone fiber. The electron microscope image thereof is shown in Figure 3 .

[0091] The maximum breaking strength of the functional polyether sulfone fiber prepared in the embodiment was 2.5 cN / dtex, and the breaking elongation was 66.48±3.42%.

[0092] Comparative Example 1

[0093] The preparation method of the functional polyether sulfone fiber of the embodiment is as follows:

[0094] (1) The polyether sulfone powder dried to absolute dryness was dissolved in DMSO, and dissolved at room temperature for 30 minutes under the action of mechanical stirring to obtain a polyether sulfone solution with a solubility of 10%; 1-allyl-3-methylimidazole hexafluorophosphate and 10% nano-TiO2 were added, and the spinning solution was obtained after sufficient stirring; the mass of polyether sulfone, 1-allyl-3-methylimidazole hexafluorophosphate and nano-TiO2 in the spinning solution was 4.15 g, 0.5 g and 0.35 g respectively.

[0095] (2) The spinning solution was filtered, vacuum oven defoamed, melt spun (temperature 380°C, winding speed 600 meters / minute), and then taken out after air drying and solidification, and then dried after being washed with water for 3 times to obtain the functional polyether sulfone fiber.

[0096] The maximum breaking strength of the functional polyether sulfone fiber prepared in the embodiment was 1.3 cN / dtex, and the breaking elongation was 64.48%.

[0097] The above merely provides the preferred embodiment of the present application, and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for preparing functional polyethersulfone fibers, characterized in that, The steps are as follows: (1) Prepare a polyethersulfone solution, add ionic liquid and functional particles under stirring to obtain a spinning solution; (2) The spinning solution in step (1) is degassed under vacuum and then spun. After being washed with water and dried, functional polyethersulfone fiber is obtained. The solvent for the polyethersulfone solution in step (1) is DMF, 1-allyl-3-methylimidazolium chloride, or DMSO; The polyethersulfone solution has a mass concentration of 10-20%; The ionic liquid is 1-allyl-3-methylimidazolium hexafluorophosphate; The functional particles are one or more of graphene oxide, graphene powder, reduced graphene oxide, silver nanoparticles, TiO2 nanoparticles, and magnetic Fe3O4 nanoparticles. The mass ratio of polyethersulfone, ionic liquid and functional particles in the spinning solution is 83:10:7; In step (2), the spinning process can be any one of electrospinning, wet spinning, or melt spinning. The parameters for electrospinning are: voltage 16-24kV, flow rate 0.3-0.8mL / h, spinning distance 7-12cm; the parameters for wet spinning are: viscosity 50-80mPa·s, coagulation bath concentration 20-80%; the parameters for melt spinning are: temperature 180-230℃, winding speed 170-250m / min.

2. Functional polyethersulfone fibers prepared using the method of claim 1.

3. The application of the functional polyethersulfone fiber according to claim 2 in the preparation of flame retardant materials, conductive materials, photocatalytically degradable dyes, and carbon fiber composite materials.

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