(1) Sequentially adding chloromethyl vinylbenzene, 6-chloro-1-hydroxybenzotriazole and sodium hydroxide into N, N-dimethylformamide solution, heating to 70-80 ℃, and reacting for 4-5 hours to obtain a compound 2, wherein the molar ratio of chloromethyl vinylbenzene to 6-chloro-1-hydroxybenzotriazole to sodium hydroxide is 1:1.1-1.2:2.0-2.5; wherein the dosage of N, N-dimethylformamide is 5-10mL/1g chloromethyl vinyl benzene, and the chemical structural formula of the compound 2 is as follows:

(2) Adding platinum dioxide into absolute ethyl alcohol, stirring until the platinum dioxide is uniformly dispersed in the absolute ethyl alcohol, slowly bubbling hydrogen into the solution, sequentially adding diethyl cyanomethylphosphate and concentrated hydrochloric acid, and reacting at room temperature for 10-12h to obtain a compound 3, wherein the molar ratio of the diethyl cyanomethylphosphate to the platinum dioxide to the concentrated hydrochloric acid is 1:0.4-0.5:2.0-2.5; the dosage of the absolute ethyl alcohol is 5-10mL/1g of diethyl cyanomethylphosphonate; the bubbling time of the hydrogen is 20-40min; the chemical structural formula of the compound 3 is as follows:

(3) Adding the compound 2 into absolute ethyl alcohol, replacing nitrogen under ice bath condition, then slowly adding an aqueous solution of the compound 3, adjusting the pH value of the reaction solution to 9-10 by using a 1mol/L sodium hydroxide solution, and reacting for 12-14h at room temperature to obtain the compound 1; the molar ratio of the compound 3 to the compound 2 is 1:1.1-1.2; the dosage of the absolute ethyl alcohol is 5-10mL/1g of the compound 3.

The invention also provides a preparation method of the regenerated polyamide fiber, which comprises the following steps: collecting polyamide waste, cleaning and drying for later use; weighing the crushed polyamide waste and modified antibacterial polypropylene according to the weight ratio, blending, extruding from spinneret orifices on a spinneret plate through melt spinning, cooling by adopting circular blowing, oiling, stretching and winding to obtain the regenerated polyamide fiber.

Further, the technological parameters of melt spinning are: the melting temperature is 240-260 ℃, the spinning temperature is 250-280 ℃, the cooling temperature is 15-25 ℃, the prestretching temperature is 70-80 ℃, the stretching temperature is 140-160 ℃, the stretching multiple is 2.7-3.3, and the winding speed is 1000-1500m/min.

The invention has the following beneficial effects:

the invention takes polypropylene as a raw material for modification, and obtains the modified antibacterial polypropylene containing rigid benzene ring, phosphate, benzotriazole and nitrogen-chloro amine structure through structural modification, wherein the rigid benzene ring structure can enhance the mechanical property of the product and improve the breaking strength of the product; the phosphate has good flame retardant effect; the benzotriazole structure has certain light stability, can shield or absorb ultraviolet energy, eliminates or slows down the possibility of photochemical reaction, and prevents or delays the photo-aging process, so that the aging resistance of the product is enhanced, and has certain corrosion inhibition property, so that the ablation of each component of the material against flame can be promoted to be exerted, and the flame retardance of the product is improved; the nitrogen-chloro amine structure has good antibacterial effect, so that the product has antibacterial property; according to the invention, the modified antibacterial polypropylene and the polyamide waste are blended, and the regenerated polyamide fiber is prepared through melt spinning, so that the regenerated polyamide fiber with good comprehensive performance is prepared while the recycling of the polyamide waste is realized.

The regenerated polyamide fiber prepared by the invention has good strength, ageing resistance, flame retardance and antibacterial property, has wide application value, and can be applied to the production of carpets, such as automobile mats, ceramic tile carpets and floor mats; and the purpose of recycling the polyamide waste is achieved, so that the waste is turned into wealth, the social resource is saved, and the environment is effectively protected.

Detailed Description

The following description of the technical solutions in the embodiments of the present application will be made clearly and completely in connection with the embodiments of the present application, and it is obvious that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.

Benzoyl peroxide CAS number 94-36-0; trichloroisocyanuric acid CAS number 87-90-1; chloromethyl vinyl benzene CAS No. 30030-25-2; 6-chloro-1-hydroxybenzotriazole CAS number 26198-19-6; sodium hydroxide CAS number 1310-73-2; cyanomethyl diethyl phosphate CAS number 2537-48-6; platinum dioxide CAS number 1314-15-4; hydrochloric acid CAS number 7647-01-0; n, N-dimethylformamide CAS number 68-12-2; xylene CAS number 1330-20-7; acetone CAS number 67-64-1; absolute ethyl alcohol CAS number 64-17-5; dichloromethane CAS number 75-09-2; petroleum ether CAS No. 8032-32-4; all chemical reagents are commercially available.

Example 1

This example provides a regenerated polyamide fiber and a method of making the same.

Regenerated polyamide fiber is prepared from 80 parts by weight of polyamide waste and 60 parts by weight of modified antibacterial polypropylene through melt spinning; wherein the polyamide waste is nylon 66 waste.

A method for preparing regenerated polyamide fibers comprising the steps of: collecting polyamide waste, cleaning and drying for later use; weighing the crushed polyamide waste and modified antibacterial polypropylene according to the weight ratio, blending, extruding from spinneret orifices on a spinneret plate through melt spinning, cooling by adopting circular blowing, oiling, stretching and winding to obtain the regenerated polyamide fiber. Wherein the technological parameters of melt spinning are as follows: the melting temperature is 260 ℃, the spinning temperature is 280 ℃, the cooling temperature is 25 ℃, the pre-stretching temperature is 70 ℃, the stretching temperature is 160 ℃, the stretching multiple is 3.0, and the winding speed is 1500m/min.

s1, adding benzoyl peroxide and a compound 1 into a xylene solution, adding polypropylene (purchased from Dongguan Hongyao plastic limited company, model 320 powder), heating to 120 ℃ under the protection of nitrogen, reacting for 3 hours, naturally cooling to room temperature, filtering, dissolving a solid in xylene at 150 ℃, stirring and refluxing for 1.5 hours, adding acetone, continuously stirring for 40 minutes, cooling to room temperature, filtering and drying to obtain modified polypropylene; wherein the dosage of the xylene is 15mL/1g of polypropylene; the mass ratio of the polypropylene to the compound 1 to the benzoyl peroxide is 1:0.2:0.02;

s2, adding trichloroisocyanuric acid into an acetone solution, then adding modified polypropylene, stirring vigorously for 3 hours at room temperature, filtering, washing with acetone for three times, and drying to obtain modified antibacterial polypropylene, wherein the content of effective active chlorine is 14.6%; wherein the mass ratio of the modified polypropylene to the trichloroisocyanuric acid to the acetone is 1:0.5:15.

The reaction process for preparing the modified antibacterial polypropylene comprises the following steps:

wherein the chemical structural formula of the compound 1 is as follows:

the preparation method comprises the following steps:

(1) Sequentially adding chloromethyl vinylbenzene, 6-chloro-1-hydroxybenzotriazole and sodium hydroxide into N, N-dimethylformamide solution, heating to 80 ℃, reacting for 5 hours, naturally cooling to room temperature, adding water (the same volume as DMF) and dichloromethane (2 times of the volume of N, N-dimethylformamide) for extraction, collecting an organic phase, and concentrating under reduced pressure to obtain a compound 2, wherein the molar ratio of chloromethyl vinylbenzene, 6-chloro-1-hydroxybenzotriazole and sodium hydroxide is 1:1.1:2.0; the dosage of the N, N-dimethylformamide is 10mL/1g chloromethyl vinyl benzene, and the reaction process is as follows:

compound 2: ESI (m/z): 286.7[ M+H ]]⁺ ，¹ H-NMR(600MHz，DMSO-d₆ ，δppm)：7.99(s，1H)，7.85(d，1H)，7.46(d，1H)，7.33-7.35(m，2H)，7.29-7.30(m，1H)，7.24-7.26(m，2H)，6.30-6.32(m，1H)，5.56(s，1H)，4.49-5.50(m，2H)。

(2) Adding platinum dioxide into absolute ethyl alcohol, stirring until the platinum dioxide is uniformly dispersed in the absolute ethyl alcohol, slowly bubbling hydrogen into the solution, sequentially adding diethyl cyanomethylphosphate and concentrated hydrochloric acid, reacting for 10 hours at room temperature, filtering to remove the platinum dioxide, removing the ethanol by rotary evaporation, and recrystallizing with dichloromethane and petroleum ether (volume ratio is 5:1), filtering and drying to obtain a compound 3, wherein the molar ratio of diethyl cyanomethylphosphate to the platinum dioxide to the concentrated hydrochloric acid is 1:0.4:2.0; the dosage of the absolute ethyl alcohol is 10mL/1g of diethyl cyanomethylphosphonate; the bubbling time of the hydrogen is 20min; the reaction process is as follows:

compound 3: ESI (m/z): 182.1[ M-Cl]⁺ ，¹ H-NMR(600MHz，DMSO-d₆ ，δppm)：8.31(s，3H)，4.19-4.20(m，4H)，3.57(t，2H)，2.51(t，2H)，1.36(t，6H)。

(3) Adding the compound 2 into absolute ethyl alcohol, replacing nitrogen under ice bath condition, then slowly adding an aqueous solution of the compound 3 (3 mL of water/1 g of the compound 3), regulating the pH value of the reaction solution to 9-10 by using a 1mol/L sodium hydroxide solution, reacting for 14 hours at room temperature, removing the ethanol by rotary evaporation, filtering to obtain a crude product, recrystallizing the crude product by using methanol and petroleum ether (volume ratio is 1:2), filtering and drying to obtain the compound 1, wherein the molar ratio of the compound 3 to the compound 2 is 1:1.1; the dosage of the absolute ethyl alcohol is 10mL/1g of the compound 3; the reaction process is as follows:

compound 1: ESI (m/z): 431.4[ M+H ]]⁺ ，¹ H-NMR(600MHz，DMSO-d₆ ，δppm)：7.86(d，1H)，7.43(s，1H)，7.33-7.35(m，2H)，7.28-7.29(m，3H)，7.25(s，1H)，6.72(d，1H)，6.30-6.32(m，1H)，5.58(s，1H)，4.49-5.50(m，2H)，4.19-4.20(m，4H)，3.34(t，2H)，2.42(t，2H)，1.35(t，6H)。

Example 2

Regenerated polyamide fiber is prepared from 50 parts by weight of polyamide waste and 40 parts by weight of modified antibacterial polypropylene through melt spinning; wherein the polyamide waste is nylon 66 waste.

A method for preparing regenerated polyamide fibers comprising the steps of: collecting polyamide waste, cleaning and drying for later use; weighing the crushed polyamide waste and modified antibacterial polypropylene according to the weight ratio, blending, extruding from spinneret orifices on a spinneret plate through melt spinning, cooling by adopting circular blowing, oiling, stretching and winding to obtain the regenerated polyamide fiber. Wherein the technological parameters of melt spinning are as follows: the melting temperature is 240 ℃, the spinning temperature is 250 ℃, the cooling temperature is 15 ℃, the pre-stretching temperature is 70 ℃, the stretching temperature is 160 ℃, the stretching multiple is 3.0, and the winding speed is 1200m/min.

Wherein the modified antibacterial polypropylene was prepared in the same manner as in example 1.

Example 3

Regenerated polyamide fiber is prepared from 60 parts by weight of polyamide waste and 50 parts by weight of modified antibacterial polypropylene through melt spinning; wherein the polyamide waste is nylon 6 waste.

A method for preparing regenerated polyamide fibers comprising the steps of: collecting polyamide waste, cleaning and drying for later use; weighing the crushed polyamide waste and modified antibacterial polypropylene according to the weight ratio, blending, extruding from spinneret orifices on a spinneret plate through melt spinning, cooling by adopting circular blowing, oiling, stretching and winding to obtain the regenerated polyamide fiber. Wherein the technological parameters of melt spinning are as follows: the melting temperature is 250 ℃, the spinning temperature is 260 ℃, the cooling temperature is 20 ℃, the pre-stretching temperature is 80 ℃, the stretching temperature is 150 ℃, the stretching multiple is 3.3, and the winding speed is 1400m/min.

Example 4

Regenerated polyamide fiber is prepared from 70 parts by weight of polyamide waste and 40 parts by weight of modified antibacterial polypropylene through melt spinning; wherein the polyamide waste is nylon 6 waste.

A method for preparing regenerated polyamide fibers comprising the steps of: collecting polyamide waste, cleaning and drying for later use; weighing the crushed polyamide waste and modified antibacterial polypropylene according to the weight ratio, blending, extruding from spinneret orifices on a spinneret plate through melt spinning, cooling by adopting circular blowing, oiling, stretching and winding to obtain the regenerated polyamide fiber. Wherein the technological parameters of melt spinning are as follows: the melting temperature is 260 ℃, the spinning temperature is 260 ℃, the cooling temperature is 25 ℃, the pre-stretching temperature is 75 ℃, the stretching temperature is 150 ℃, the stretching multiple is 2.7, and the winding speed is 1000m/min.

Comparative example 1

This comparative example provides a regenerated polyamide fiber and a method for producing the same, differing from example 1 in that the regenerated polyamide fiber is produced by melt spinning 80 parts by weight of a polyamide waste material and 60 parts by weight of a modified polypropylene; wherein the polyamide waste is nylon 66 waste.

The method for producing the regenerated polyamide fiber and the method for producing the modified polypropylene are the same as in example 1.

Comparative example 2

This comparative example provides a regenerated polyamide fiber and a method for producing the same, differing from example 1 in that the regenerated polyamide fiber is produced by melt spinning 80 parts by weight of a polyamide waste material and 60 parts by weight of polypropylene; wherein the polyamide waste is nylon 66 waste.

The regenerated polyamide fiber was produced in the same manner as in example 1.

Comparative example 3

This comparative example provides a regenerated polyamide fiber and a method for producing the same, differing from example 1 in that the regenerated polyamide fiber is produced from 80 parts by weight of a polyamide waste material by melt spinning; wherein the polyamide waste is nylon 66 waste.

Test example 1

The regenerated polyamide fibers prepared in examples 1 to 4 and comparative examples 1 to 3 were respectively subjected to a total fineness, breaking strength, elongation at break tensile property test; the breaking strength and breaking elongation test method refers to GB/T3916-2013; anti-aging test is referred to GB/T16991-2008; the test results are shown in Table 1.

Table 1 correlation performance test table

As can be seen from the comparison results of Table 1, the total fineness of the regenerated polyamide fibers prepared in examples 1-4 is 1750-2000dtex, and the regenerated polyamide fibers have certain wear resistance while ensuring the softness, and the breaking strength and the breaking elongation before and after aging are far greater than those of comparative examples 1-3; compared with the modified polypropylene (added) in the comparative example 1, the modified polypropylene (added) in the comparative example 2 and the comparative example 3 (only polyamide waste is used), the rigid benzene ring on the molecular chain of the modified antibacterial polypropylene added in the example 1 can enhance the mechanical property of the product, improve the breaking strength of the product, enable the benzotriazole structure to have certain light stability, shield or absorb the energy of ultraviolet rays, eliminate or slow down the possibility of photochemical reaction and prevent or delay the photo-aging process, thereby enhancing the aging resistance of the product and ensuring that the breaking strength of the product before and after aging is not obviously changed basically; the invention shows that the modified antibacterial polypropylene and the polyamide waste material are blended and melt-spun, and the regenerated polyamide fiber with good strength and ageing resistance can be prepared.

Test example 2

The regenerated polyamide fibers prepared in examples 1 to 4 and comparative examples 1 to 3 were subjected to flame retardant and antibacterial property test, and the oxygen index test method was referred to GB/T2406-2009; testing the antibacterial effect on staphylococcus aureus and escherichia coli; the test results are shown in Table 2.

TABLE 2 flame retardant and antibacterial Property test Table

As can be seen from the comparison results of Table 2, the limiting oxygen index of the regenerated polyamide fibers prepared in examples 1-4 is 31-34%, the antibacterial rate against staphylococcus aureus is more than 98%, the antibacterial rate against escherichia coli is more than 99%, and the flame retardant and antibacterial properties of the regenerated polyamide fibers are far better than those of comparative examples 1-3; compared with the modified polypropylene (added) in the comparative example 1, the modified polypropylene (added) in the comparative example 2 and the comparative example 3 (only polyamide waste is used), the phosphate on the molecular chain of the modified antibacterial polypropylene added in the example 1 has flame retardant effect, and the benzotriazole structure also has certain corrosion inhibition property, so that the flame resistance of each component of the material against flame can be promoted to be exerted, and the flame resistance of the product is improved; the nitrogen-chloro amine has the antibacterial effect, is realized by directly acting hydrolytic release oxidative halogen and microorganism, and shows that the invention blends and melt-spins modified antibacterial polypropylene and polyamide waste, and can prepare regenerated polyamide fiber with good flame retardance and antibacterial property.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Furthermore, it should be understood that although the present disclosure describes embodiments, not every embodiment is provided with a separate embodiment, and that this description is provided for clarity only, and that the disclosure is not limited to the embodiments described in detail below, and that the embodiments described in the examples may be combined as appropriate to form other embodiments that will be apparent to those skilled in the art.

Claims

1. Regenerated polyamide fiber, characterized in that the regenerated polyamide fiber is prepared from 50-80 parts by weight of polyamide waste and 40-60 parts by weight of modified antibacterial polypropylene through melt spinning; the preparation method of the modified antibacterial polypropylene comprises the following steps:

s1, adding benzoyl peroxide and a compound 1 into a xylene solution, adding polypropylene, heating to 110-130 ℃ under the protection of nitrogen, reacting for 2-4 hours, naturally cooling to room temperature, filtering, taking a solid, dissolving the solid in the xylene at 140-150 ℃, stirring and refluxing for 0.5-1.5 hours, adding acetone, continuously stirring for 20-40 minutes, cooling to room temperature, filtering and drying to obtain modified polypropylene;

s2, adding trichloroisocyanuric acid into an acetone solution, then adding modified polypropylene, vigorously stirring for 2-3 hours at room temperature, filtering, washing with acetone for three times, and drying to obtain modified antibacterial polypropylene;

the chemical structural formula of the compound 1 is as follows:

2. the regenerated polyamide fiber according to claim 1, wherein the preparation method of the compound 1 is:

(1) Sequentially adding chloromethyl vinylbenzene, 6-chloro-1-hydroxybenzotriazole and sodium hydroxide into N, N-dimethylformamide solution, heating to 70-80 ℃, and reacting for 4-5h to obtain a compound 2 with a chemical structural formula:

(2) Adding platinum dioxide into absolute ethyl alcohol, stirring until the platinum dioxide is uniformly dispersed in the absolute ethyl alcohol, slowly bubbling hydrogen into the solution, sequentially adding diethyl cyanomethylphosphate and concentrated hydrochloric acid, and reacting at room temperature for 10-12h to obtain a compound 3, wherein the chemical structural formula is as follows:

(3) Adding the compound 2 into absolute ethyl alcohol, replacing nitrogen under ice bath condition, then slowly adding an aqueous solution of the compound 3, adjusting the pH value of the reaction solution to 9-10 by using a 1mol/L sodium hydroxide solution, and reacting for 12-14h at room temperature to obtain the compound 1.

3. The regenerated polyamide fiber according to claim 2 wherein the chloromethylvinylbenzene, 6-chloro-1-hydroxybenzotriazole, sodium hydroxide in step (1) are in a molar ratio of 1:1.1-1.2:2.0-2.5; the molar ratio of the cyanomethyl diethyl phosphate, the platinum dioxide and the concentrated hydrochloric acid in the step (2) is 1:0.4-0.5:2.0-2.5; the molar ratio of the compound 3 to the compound 2 in the step (3) is 1:1.1-1.2.

4. The recycled polyamide fiber of claim 1, wherein the polyamide waste is nylon 66 waste or nylon 6 waste.

5. The regenerated polyamide fiber according to claim 1, wherein the mass ratio of the polypropylene, the compound 1 and the benzoyl peroxide in the step S1 is 1:0.2-0.3:0.01-0.02; and in the step S2, the mass ratio of the modified polypropylene to the trichloroisocyanuric acid to the acetone is 1:0.5-0.6:15-20.

6. The method for producing a regenerated polyamide fiber according to any one of claims 1 to 5, comprising the steps of: collecting polyamide waste, cleaning and drying for later use; weighing the crushed polyamide waste and modified antibacterial polypropylene according to the weight ratio, blending, extruding from spinneret orifices on a spinneret plate through melt spinning, cooling by adopting circular blowing, oiling, stretching and winding to obtain the regenerated polyamide fiber.

7. The method of producing a regenerated polyamide fiber according to claim 6 wherein the melting temperature is 240-260 ℃.

8. The method for producing a regenerated polyamide fiber according to claim 6, wherein the spinning temperature is 250 to 280 ℃, the cooling temperature is 15 to 25 ℃, the pre-stretching temperature is 70 to 80 ℃, the stretching temperature is 140 to 160 ℃, the stretching multiple is 2.7 to 3.3, and the winding speed is 1000 to 1500m/min.