High-toughness regenerated polyester material for chemical fibers and processing method thereof

Abstract

The application discloses a high-toughness regenerated polyester material for chemical fibers and a processing method thereof, and relates to the technical field of polyester material regeneration. In the application, a modified nitrile rubber is obtained by introducing a hyperbranched structure and a polycaprolactone segment into the molecular chain of the nitrile rubber, so as to further improve the toughness, flexibility and ductility of the nitrile rubber. Moreover, a montmorillonite with a hyperbranched polyester grafted on the surface is prepared, the interlayer spacing of the montmorillonite is expanded, and the thermal stability of the material is improved. In addition, quaternary ammonium salt and polysiloxane are introduced into the hyperbranched polyester, so that the regenerated polyester material has good lubricity and antistatic property. The hyperbranched structure has no chain entanglement, and in combination with the lubricity of the polysiloxane, the processing fluidity of the polyester material is reduced, so that subsequent injection molding or extrusion is facilitated.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of polyester material regeneration, and particularly relates to a high-toughness regenerated polyester material for chemical fibers and a processing method thereof. BACKGROUND

[0002] The regenerated PET chip technology can recycle and reuse waste PET materials (such as waste textiles, waste plastic bottles and the like), realizes cyclic reuse, reduces the demand for new raw materials, and reduces energy consumption and environmental pollution. Through the chemical regeneration PET chip production process, the waste polyester can be converted into high-quality new polyester fibers, thereby reducing the dependence on petroleum resources.

[0003] The chemical method is to depolymerize the waste polyester into small molecules, and the small molecules are polymerized again after purification to obtain regenerated polyester. However, in the prior art, there are problems such as low reaction efficiency of the melt polycondensation chain extension technology, poor compatibility of the added elastomer with the polyester, and lack of functionality.

[0004] Therefore, the application provides a high-toughness regenerated polyester material for chemical fibers and a processing method thereof, which solves the problems in the prior art by preparing a high-toughness material that is compatible with the polyester material. SUMMARY

[0005] The application aims to provide a high-toughness regenerated polyester material for chemical fibers and a processing method thereof to solve the problems in the prior art.

[0006] To achieve the above-mentioned purpose, the application provides the following technical scheme: a processing method of a high-toughness regenerated polyester material for chemical fibers, comprising the following steps:

[0007] The waste polyester material is dried and melt-extruded, mixed with ethylene glycol, and subjected to a depolymerization reaction to obtain a depolymerization liquid. The ethylene glycol is subjected to vacuum distillation, and an epoxy chain extender is added and subjected to heating and stirring reaction. Then, modified nitrile rubber, hyperbranched polyester grafted montmorillonite, an accelerator and an antioxidant are added, and the mixture is subjected to copolymerization reaction and polycondensation reaction in sequence to obtain the high-toughness regenerated polyester material.

[0008] Further, the mass ratio of the waste polyester material, the ethylene glycol, the epoxy chain extender, the modified nitrile rubber, the hyperbranched polyester grafted montmorillonite, the accelerator and the antioxidant is 100: (0.5-1.5): (0.5-0.7): (25-45): (10-20): (0.3-0.5): (0.5-1.0).

[0009] Further, the epoxy chain extender is chain extender 6059.

[0010] The antioxidant is a mixture of one or more of antioxidant 1010, antioxidant 1076 and antioxidant 168.

[0011] The accelerator is N,N-dimethylaniline, N,N-diethylaniline, triethylamine.

[0012] Further, the temperature of the melt extrusion is 255-285℃;

[0013] The process conditions of the depolymerization reaction are: temperature 180-230℃, time 60-120min, pressure 0.50-0.15MPa;

[0014] The process conditions of the reduced pressure distillation are: temperature 120-130℃, time 1-3h, pressure 8-12mmHg.

[0015] Further, the process conditions of the copolymerization reaction are: temperature 225-235℃, time 40-60min;

[0016] The process conditions of the polycondensation reaction are: temperature 265-275℃, time 40-60min, pressure 1.0-1.4kPa.

[0017] Further, the modified nitrile rubber is prepared by the following process:

[0018] Step 1: mixing the terminal amino liquid nitrile rubber and the polyepoxy compound, heating and reacting under the protection of nitrogen atmosphere to obtain the epoxy-terminated nitrile rubber;

[0019] Step 2: mixing the epoxy-terminated nitrile rubber, tetrabutylammonium hydroxide and the polyhydroxy compound, heating and reacting to obtain the hyperbranched nitrile rubber;

[0020] Step 3: mixing the hyperbranched nitrile rubber, caprolactone and tetrabutylammonium hydroxide, heating and reacting to obtain the modified nitrile rubber.

[0021] Further, in Step 1, the mass ratio of the terminal amino liquid nitrile rubber and the polyepoxy compound is 1:(3-5);

[0022] The polyepoxy compound is one or a mixture of more than one of glyceryl triglycidyl ether, trimethylolpropane triglycidyl ether and epoxidized soybean oil.

[0023] Further, in Step 1, the process conditions of the heating and reaction are: temperature 150-170℃, time 1-2h.

[0024] Further, in Step 2, the mass ratio of the epoxy-terminated nitrile rubber, tetrabutylammonium hydroxide and the polyhydroxy compound is 10:(0.3-0.5):(2-4);

[0025] The polyhydroxy compound is one or a mixture of both of bistrimethylolpropane and dipentaerythritol.

[0026] Further, in step 2, the process conditions for heating reaction are: temperature 90-120℃, time 10-20h.

[0027] Further, in step 3, the mass ratio of hyperbranched nitrile rubber, caprolactone and tetrabutylammonium hydroxide is 10: (30-50): (0.01-0.03).

[0028] Further, in step 3, the process conditions for heating reaction are: temperature 80-100℃, time 5-10h.

[0029] In the above technical solution, the amino group of the terminal amino liquid nitrile rubber is used to initiate the ring opening of the epoxy group of the polyepoxide compound, and the polyepoxide compound is controlled to be in excess, so as to obtain an epoxy-terminated nitrile rubber. Then, the polyhydroxy compound is used to initiate the ring opening of the epoxy group of the epoxy-terminated nitrile rubber under the action of tetrabutylammonium hydroxide, so as to form an ether bond and a new hydroxyl group. The polyhydroxy compound is used as a reaction center, the hydroxyl group on the polyhydroxy compound reacts with multiple epoxy groups, the branching point increases, a hyperbranched structure is formed, and a hyperbranched nitrile rubber is obtained. Finally, the hydroxyl group on the hyperbranched nitrile rubber is used to initiate the ring opening polymerization of caprolactone under the action of tetrabutylammonium hydroxide, so as to form an ester bond, and a modified nitrile rubber is obtained.

[0030] The nitrile rubber itself has good toughness, the hyperbranched structure can disperse stress, cooperates with the nitrile rubber, and introduces the polycaprolactone, so as to further improve the toughness, flexibility and ductility of the nitrile rubber. In addition, the hyperbranched polymer has good flowability, is convenient for processing and molding, the polycaprolactone segment has good compatibility with polyester materials, can reduce phase separation, and can improve the mechanical properties of the materials.

[0031] Further, the preparation process of the hyperbranched polyester grafted montmorillonite is as follows:

[0032] S1: The polymethylhydrogen siloxane is mixed with (N,N-dimethyl-3-aminopropyl) trimethoxysilane and tetrabutylammonium hydroxide, heated and reacted, rotary evaporated, and distilled under reduced pressure to obtain aminated polysiloxane;

[0033] S2: The aminated polysiloxane is mixed with an ethyl chloroacetate solution, heated and reacted, and distilled under reduced pressure to obtain quaternary ammonium aminated polysiloxane;

[0034] S3: The montmorillonite is dispersed in an ethanol aqueous solution, ultrasonically dispersed, and then the quaternary ammonium aminated polysiloxane is added and heated and reacted. After suction filtration, washing and drying, modified montmorillonite is obtained.

[0035] S4: taking the modified montmorillonite dispersed in xylene, first adding p-toluenesulfonic acid and 1 / 2 mass component of dimethylol propionic acid, heating and refluxing, then adding the remaining dimethylol propionic acid, continuing to react for 2-4h, filtering, washing and drying to obtain hyperbranched polyester grafted montmorillonite.

[0036] Further, in S1, the mass ratio of polymethylhydrogen siloxane to (N,N-dimethyl-3-aminopropyl) trimethoxysilane, tetramethylammonium hydroxide is 10: (8-10): (0.01-0.03);

[0037] In S1, the polymethylhydrogen siloxane is end polymethylhydrogen siloxane DY-H201.

[0038] Further, in S1, the process conditions for heating reaction are: temperature 90-120℃, time 7-8h;

[0039] In S1, the process conditions for rotary evaporation are: temperature 130-135℃, time 10-20min;

[0040] In S1, the process conditions for vacuum distillation are: temperature 100-105℃, time 10-20min, pressure 0.01-0.03MPa.

[0041] Further, in S2, the mass ratio of aminosilicone to ethyl chloroacetate solution is 10: (4-5);

[0042] The ethyl chloroacetate solution is obtained by mixing ethyl chloroacetate and isopropyl alcohol at a mass ratio of 1:10.

[0043] Further, in S2, the process conditions for heating reaction are: temperature 75-80℃, time 2-4h;

[0044] In S2, the process conditions for vacuum distillation are: temperature 140-150℃, time 5-10min, pressure 0.01-0.03MPa.

[0045] Further, in S3, the mass ratio of montmorillonite, ethanol aqueous solution, quaternary ammonium aminosilicone is 10: (40-50): (8-10);

[0046] The mass fraction of the ethanol aqueous solution is 50-60%.

[0047] Further, in S3, the process conditions for ultrasonic dispersion are: frequency 20-40kHz, time 20-30min.

[0048] Further, in S3, the process conditions for heating reaction are: temperature 80-100℃, time 2-3h;

[0049] In S3, the dry process conditions are: temperature 60-70 DEG C, time 4-6h.

[0050] Further, in S4, the mass ratio of modified montmorillonite, dimethylbenzene, dimethylol propionic acid and p-toluene sulfonic acid is 1:(20-30):(0.3-0.5):(0.03-0.10).

[0051] Further, in S4, the process conditions of heating and reflux reaction are: temperature 140-150 DEG C, time 2-4h.

[0052] In S4, the dry process conditions are: temperature 55-65 DEG C, time 10-12h.

[0053] In the above technical solution, first, Si-H of polymethylhydrogen siloxane and Si-OCH3 of (N,N-dimethyl-3-aminopropyl) trimethoxysilane are subjected to condensation reaction to introduce tertiary amino group, to obtain aminated polysiloxane, then, ethyl chloroacetate and the tertiary amino group are subjected to quaternary ammonium reaction to generate quaternary ammonium salt, to retain ester group, to obtain quaternized aminated polysiloxane; the quaternary ammonium salt cation of the quaternized aminated polysiloxane is subjected to ion exchange with interlayer cation of montmorillonite, to insert the polysiloxane hydrophobic chain segment into the interlayer, to expand the interlayer distance, to obtain modified montmorillonite, finally, the retained ester group and dimethylol propionic acid are subjected to ester exchange reaction under the action of p-toluene sulfonic acid, and the dimethylol propionic acid itself is subjected to self-polymerization to form hyperbranched structure, to obtain hyperbranched polyester grafted montmorillonite.

[0054] The synthesized quaternized polysiloxane can effectively expand the interlayer distance of montmorillonite, is more prone to be exfoliated into single layers in the matrix, enhances the mechanical properties of the material, the polysiloxane can also improve the thermal stability of the material, reduces degradation in the processing process, the quaternary ammonium salt has good antistatic property, the synergistic effect of the siloxane and the quaternary ammonium group can impart good lubricity and antistatic property to the regenerated polyester material, the hyperbranched structure has no chain entanglement, in combination with the lubricity of the polysiloxane, can also reduce the processing fluidity of the polyester material, facilitating subsequent injection molding or extrusion.

[0055] Compared with the prior art, the present application has the following beneficial effects:

[0056] 1. The depolymerization liquid of the waste polyester material is modified by an epoxy chain extender, epoxy groups are introduced, then modified butyl nitrile rubber with hydroxyl or carboxyl on the surface and hyperbranched polyester grafted montmorillonite are added, ring opening of the epoxy groups is initiated, the flexible butyl nitrile rubber chain segment is threaded in the polyester network, and an interpenetrating network structure is formed, so that the toughness of the regenerated polyester material is improved.

[0057] 2, The nitrile rubber itself has good toughness, the hyperbranched structure can disperse stress, cooperates with the nitrile rubber, and poly (caprolactone) is introduced, further improving the toughness, flexibility and ductility of the nitrile rubber, in addition, the hyperbranched polymer has good fluidity, which is convenient for processing and molding, the poly (caprolactone) segment has good compatibility with polyester materials, which can reduce phase separation and improve the mechanical properties of the materials.

[0058] 3, The quaternary ammonium polysiloxane can effectively expand the interlayer spacing of the montmorillonite, which is more prone to peeling into single layers in the matrix, thereby enhancing the mechanical properties of the material, the polysiloxane can also improve the thermal stability of the material and reduce degradation during processing, the quaternary ammonium salt has good antistatic property, and the synergistic effect of the siloxane and the quaternary ammonium group can impart good lubricity and antistatic property to the regenerated polyester material, the hyperbranched structure has no chain entanglement, and in combination with the lubricity of the polysiloxane, the processing fluidity of the polyester material can be reduced, facilitating subsequent injection molding or extrusion. DETAILED DESCRIPTION

[0059] The technical solutions in the embodiments of the present application will be described below in a clear and complete manner. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0060] In the following specific embodiments,

[0061] The waste polyester material is from Huai'an Ruiyi Kegao Polymer Technology Co., Ltd.;

[0062] The accelerator is N,N-dimethylaniline;

[0063] The antioxidant is antioxidant 1010;

[0064] The epoxy chain extender is chain extender 6059;

[0065] The amino-terminated liquid nitrile rubber is with the item number xyh001 and from Hubei Xinyu Hong Biological Medicine Technology Co., Ltd.;

[0066] The polyepoxy compound is glycerol triglycidyl ether;

[0067] The polyhydroxy compound is ditrimethylolpropane;

[0068] The montmorillonite is 200 mesh;

[0069] The polymethylhydrogen siloxane is end polymethylhydrogen siloxane DY-H201;

[0070] The carboxyl-terminated nitrile rubber is with the item number lnb-136 and from Wuhan Lana Bai Medicine Chemical Co., Ltd.;

[0071] Preparation of ethyl chloroacetate solution: ethyl chloroacetate and isopropyl alcohol are mixed in a mass ratio of 1:10 to prepare the ethyl chloroacetate solution.

[0072] Example 1: a processing method of high-toughness regenerated polyester material for chemical fibers, comprising the following steps:

[0073] (1) Preparation of hyperbranched polyester grafted montmorillonite:

[0074] S1: mixing polymethylhydrogen siloxane, (N,N-dimethyl-3-aminopropyl) trimethoxysilane and tetramethylammonium hydroxide, heating and reacting, rotary evaporation, and vacuum distillation to obtain aminated polysiloxane; S2: mixing the aminated polysiloxane with the ethyl chloroacetate solution, heating and reacting, and vacuum distillation to obtain quaternary aminated polysiloxane; S3: dispersing montmorillonite in an ethanol aqueous solution, ultrasonic dispersion, adding the quaternary aminated polysiloxane, heating and reacting, suction filtration, washing, and drying to obtain modified montmorillonite; S4: dispersing the modified montmorillonite in dimethylbenzene, first adding p-toluenesulfonic acid and 1 / 2 mass component of dimethylol propionic acid, heating and refluxing, then adding the remaining dimethylol propionic acid, continuing to react for 4 h, suction filtration, washing, and drying to obtain hyperbranched polyester grafted montmorillonite; in S1, the mass ratio of polymethylhydrogen siloxane, (N,N-dimethyl-3-aminopropyl) trimethoxysilane and tetramethylammonium hydroxide is 10:10:0.03; in S1, the process conditions for heating and reacting are: temperature 120℃, time 8 h; in S1, the process conditions for rotary evaporation are: temperature 135℃, time 20 min; in S1, the process conditions for vacuum distillation are: temperature 105℃, time 20 min, and pressure 0.03 MPa; in S2, the mass ratio of the aminated polysiloxane and the ethyl chloroacetate solution is 10:5; in S2, the process conditions for heating and reacting are: temperature 80℃, time 4 h; in S2, the process conditions for vacuum distillation are: temperature 150℃, time 10 min, and pressure 0.03 MPa; in S3, the mass ratio of the montmorillonite, the ethanol aqueous solution, and the quaternary aminated polysiloxane is 10:50:10; the mass fraction of the ethanol aqueous solution is 60%; in S3, the process conditions for ultrasonic dispersion are: frequency 40 kHz, time 30 min; in S3, the process conditions for heating and reacting are: temperature 100℃, time 3 h; in S3, the process conditions for drying are: temperature 70℃, time 6 h; in S4, the mass ratio of the modified montmorillonite, dimethylbenzene, dimethylol propionic acid, and p-toluenesulfonic acid is 1:30:0.5:0.10; in S4, the process conditions for heating and refluxing are: temperature 150℃, time 4 h; in S4, the process conditions for drying are: temperature 65℃, time 12 h.

[0075] (2) Preparation of modified nitrile rubber:

[0076] Step 1: mixing the terminal amino liquid nitrile rubber and the multi-epoxy compound, heating and reacting under the protection of nitrogen atmosphere to obtain the epoxy-terminated nitrile rubber; Step 2: mixing the epoxy-terminated nitrile rubber, tetrabutylammonium hydroxide and the multi-hydroxyl compound, heating and reacting to obtain the hyperbranched nitrile rubber; Step 3: mixing the hyperbranched nitrile rubber, caprolactone and tetrabutylammonium hydroxide, heating and reacting to obtain the modified nitrile rubber; in Step 1, the mass ratio of the terminal amino liquid nitrile rubber to the multi-epoxy compound is 1:5; in Step 1, the process conditions for heating and reacting are that the temperature is 170℃ and the time is 2h; in Step 2, the mass ratio of the epoxy-terminated nitrile rubber, tetrabutylammonium hydroxide to the multi-hydroxyl compound is 10:0.5:4; in Step 2, the process conditions for heating and reacting are that the temperature is 120℃ and the time is 20h; in Step 3, the process conditions for heating and reacting are that the temperature is 100℃ and the time is 10h;

[0077] (3) Preparation of the regenerated polyester material:

[0078] The waste polyester material is dried, melt-extruded, mixed with ethylene glycol, and subjected to depolymerization reaction to obtain a depolymerization liquid, ethylene glycol is distilled under reduced pressure, an epoxy chain extender is added, heated and stirred to react, cooled, and then modified nitrile rubber, hyperbranched polyester grafted montmorillonite, an accelerator and an antioxidant are added to sequentially perform copolymerization reaction and polycondensation reaction to obtain a high-toughness regenerated polyester material; the mass ratio of the waste polyester material, ethylene glycol, epoxy chain extender, modified nitrile rubber, hyperbranched polyester grafted montmorillonite, accelerator and antioxidant is 100:1.5:0.7:45:20:0.5:1.0; the temperature for melt-extrusion is 285℃; the process conditions for depolymerization reaction are that the temperature is 230℃, the time is 120min and the pressure is 0.15MPa; the process conditions for distillation under reduced pressure are that the temperature is 130℃, the time is 3h and the pressure is 12mmHg; the process conditions for copolymerization reaction are that the temperature is 235℃ and the time is 60min; the process conditions for polycondensation reaction are that the temperature is 275℃, the time is 60min and the pressure is 1.4kPa.

[0079] Example 2: A processing method of a high-toughness regenerated polyester material for chemical fibers, comprising the following steps:

[0080] (1) Preparation of the hyperbranched polyester grafted montmorillonite:

[0081] S1: mixing polymethylhydrogen siloxane with (N,N-dimethyl-3-aminopropyl) trimethoxysilane and tetramethylammonium hydroxide, heating and reacting, rotary evaporation, and vacuum distillation to obtain aminated polysiloxane; S2: mixing the aminated polysiloxane with an ethyl chloroacetate solution, heating and reacting, and vacuum distillation to obtain quaternary ammonium aminated polysiloxane; S3: dispersing montmorillonite in an ethanol aqueous solution, ultrasonic dispersion, adding the quaternary ammonium aminated polysiloxane, heating and reacting, suction filtration, washing, and drying to obtain modified montmorillonite; S4: dispersing the modified montmorillonite in xylene, first adding p-toluenesulfonic acid and 1 / 2 mass fraction of dimethylol propionic acid, heating and refluxing to react, then adding the remaining dimethylol propionic acid, continuing to react for 3 h, suction filtration, washing, and drying to obtain hyperbranched polyester grafted montmorillonite; in S1, the mass ratio of polymethylhydrogen siloxane to (N,N-dimethyl-3-aminopropyl) trimethoxysilane and tetramethylammonium hydroxide is 10:9:0.02; in S1, the process conditions for heating and reacting are: temperature 110℃, time 7.5 h; in S1, the process conditions for rotary evaporation are: temperature 133℃, time 15 min; in S1, the process conditions for vacuum distillation are: temperature 103℃, time 15 min, and pressure 0.02 MPa; in S2, the mass ratio of aminated polysiloxane to the ethyl chloroacetate solution is 10:4.5; in S2, the process conditions for heating and reacting are: temperature 78℃, time 3 h; in S2, the process conditions for vacuum distillation are: temperature 145℃, time 8 min, and pressure 0.02 MPa; in S3, the mass ratio of montmorillonite, the ethanol aqueous solution, and the quaternary ammonium aminated polysiloxane is 10:45:9; the mass fraction of the ethanol aqueous solution is 55%; in S3, the process conditions for ultrasonic dispersion are: frequency 30 kHz, time 25 min; in S3, the process conditions for heating and reacting are: temperature 90℃, time 2.5 h; in S3, the process conditions for drying are: temperature 65℃, time 5 h; in S4, the mass ratio of modified montmorillonite, xylene, dimethylol propionic acid, and p-toluenesulfonic acid is 1:25:0.4:0.07; in S4, the process conditions for heating and refluxing to react are: temperature 145℃, time 3 h; in S4, the process conditions for drying are: temperature 60℃, time 11 h;

[0082] (2) Preparation of modified butyl nitrile rubber:

[0083] Step 1: mixing the terminal amino liquid nitrile rubber and the multi-epoxy compound, heating and reacting under the protection of nitrogen atmosphere to obtain the epoxy-terminated nitrile rubber; Step 2: mixing the epoxy-terminated nitrile rubber, tetrabutylammonium hydroxide and the multi-hydroxyl compound, heating and reacting to obtain the hyperbranched nitrile rubber; Step 3: mixing the hyperbranched nitrile rubber, caprolactone and tetrabutylammonium hydroxide, heating and reacting to obtain the modified nitrile rubber; in Step 1, the mass ratio of the terminal amino liquid nitrile rubber to the multi-epoxy compound is 1:4; in Step 1, the process conditions for heating and reacting are that the temperature is 160℃ and the time is 1.5h; in Step 2, the mass ratio of the epoxy-terminated nitrile rubber, tetrabutylammonium hydroxide to the multi-hydroxyl compound is 10:0.4:3; in Step 2, the process conditions for heating and reacting are that the temperature is 110℃ and the time is 15h; in Step 3, the process conditions for heating and reacting are that the temperature is 90℃ and the time is 8h;

[0084] (3) Preparation of the regenerated polyester material:

[0085] The waste polyester material is dried, melt-extruded, mixed with ethylene glycol, and subjected to depolymerization reaction to obtain a depolymerization liquid, ethylene glycol is distilled under reduced pressure, an epoxy chain extender is added, heated and stirred to react, cooled, and then modified nitrile rubber, hyperbranched polyester grafted montmorillonite, an accelerator and an antioxidant are added to sequentially perform copolymerization reaction and polycondensation reaction to obtain a high-toughness regenerated polyester material; the mass ratio of the waste polyester material, ethylene glycol, epoxy chain extender, modified nitrile rubber, hyperbranched polyester grafted montmorillonite, accelerator and antioxidant is 100:1.0:0.6:35:15:0.4:0.8; the temperature for melt-extrusion is 270℃; the process conditions for depolymerization reaction are that the temperature is 200℃, the time is 90min and the pressure is 0.10MPa; the process conditions for distillation under reduced pressure are that the temperature is 125℃, the time is 2h and the pressure is 10mmHg; the process conditions for copolymerization reaction are that the temperature is 230℃ and the time is 50min; the process conditions for polycondensation reaction are that the temperature is 270℃, the time is 50min and the pressure is 1.2kPa.

[0086] Example 3: A processing method of a high-toughness regenerated polyester material for chemical fibers, comprising the following steps:

[0087] (1) Preparation of the hyperbranched polyester grafted montmorillonite:

[0088] S1: mixing polymethylhydrogen siloxane with (N,N-dimethyl-3-aminopropyl) trimethoxysilane and tetramethylammonium hydroxide, heating and reacting, rotary evaporation, and reduced pressure distillation to obtain aminated polysiloxane; S2: mixing the aminated polysiloxane with an ethyl chloroacetate solution, heating and reacting, and reduced pressure distillation to obtain quaternary ammonium aminated polysiloxane; S3: dispersing montmorillonite in an ethanol aqueous solution, ultrasonic dispersion, adding the quaternary ammonium aminated polysiloxane, heating and reacting, suction filtration, washing, and drying to obtain modified montmorillonite; S4: dispersing the modified montmorillonite in xylene, first adding p-toluenesulfonic acid and 1 / 2 mass fraction of dimethylol propionic acid, heating and refluxing to react, then adding the remaining dimethylol propionic acid, continuing to react for 2 h, suction filtration, washing, and drying to obtain hyperbranched polyester grafted montmorillonite; in S1, the mass ratio of polymethylhydrogen siloxane to (N,N-dimethyl-3-aminopropyl) trimethoxysilane and tetramethylammonium hydroxide is 10:8:0.01; in S1, the process conditions for heating and reacting are: temperature 90℃, time 7 h; in S1, the process conditions for rotary evaporation are: temperature 130℃, time 10 min; in S1, the process conditions for reduced pressure distillation are: temperature 100℃, time 10 min, and pressure 0.01 MPa; in S2, the mass ratio of aminated polysiloxane to the ethyl chloroacetate solution is 10:4; in S2, the process conditions for heating and reacting are: temperature 75℃, time 2 h; in S2, the process conditions for reduced pressure distillation are: temperature 140℃, time 5 min, and pressure 0.01 MPa; in S3, the mass ratio of montmorillonite, the ethanol aqueous solution, and the quaternary ammonium aminated polysiloxane is 10:40:8; the mass fraction of the ethanol aqueous solution is 50%; in S3, the process conditions for ultrasonic dispersion are: frequency 20 kHz, time 20 min; in S3, the process conditions for heating and reacting are: temperature 80℃, time 2 h; in S3, the process conditions for drying are: temperature 60℃, time 4 h; in S4, the mass ratio of modified montmorillonite, xylene, dimethylol propionic acid, and p-toluenesulfonic acid is 1:20:0.3:0.03; in S4, the process conditions for heating and refluxing to react are: temperature 140℃, time 2 h; in S4, the process conditions for drying are: temperature 55℃, time 10 h;

[0089] (2) Preparation of modified butyl nitrile rubber:

[0090] Step 1: mixing the terminal amino liquid nitrile rubber and the multi-epoxy compound, and heating to react under the protection of nitrogen atmosphere to obtain the epoxy-terminated nitrile rubber; Step 2: mixing the epoxy-terminated nitrile rubber, tetrabutylammonium hydroxide and the multi-hydroxyl compound, and heating to react to obtain the hyperbranched nitrile rubber; Step 3: mixing the hyperbranched nitrile rubber, caprolactone and tetrabutylammonium hydroxide, and heating to react to obtain the modified nitrile rubber; in Step 1, the mass ratio of the terminal amino liquid nitrile rubber to the multi-epoxy compound is 1:3; in Step 1, the process conditions for heating to react are that the temperature is 150℃ and the time is 1h; in Step 2, the mass ratio of the epoxy-terminated nitrile rubber, tetrabutylammonium hydroxide to the multi-hydroxyl compound is 10:0.3:2; in Step 2, the process conditions for heating to react are that the temperature is 90℃ and the time is 10h; in Step 3, the process conditions for heating to react are that the temperature is 80℃ and the time is 5h;

[0091] (3) Preparation of the regenerated polyester material:

[0092] The waste polyester material is dried, melt-extruded, mixed with ethylene glycol, and subjected to depolymerization reaction to obtain a depolymerization liquid, ethylene glycol is distilled under reduced pressure, an epoxy chain extender is added, heated and stirred to react, cooled, and then modified nitrile rubber, hyperbranched polyester grafted montmorillonite, an accelerator and an antioxidant are added to sequentially perform copolymerization reaction and polycondensation reaction to obtain a high-toughness regenerated polyester material; the mass ratio of the waste polyester material, ethylene glycol, epoxy chain extender, modified nitrile rubber, hyperbranched polyester grafted montmorillonite, accelerator and antioxidant is 100:0.5:0.5:25:10:0.3:0.5; the temperature for melt-extrusion is 255℃; the process conditions for the depolymerization reaction are that the temperature is 180℃, the time is 60min and the pressure is 0.50MPa; the process conditions for the distillation under reduced pressure are that the temperature is 120℃, the time is 1h and the pressure is 8mmHg; the process conditions for the copolymerization reaction are that the temperature is 225℃ and the time is 40min; and the process conditions for the polycondensation reaction are that the temperature is 265℃, the time is 40min and the pressure is 1.0kPa.

[0093] Comparative Example 1: taking Example 1 as a comparison, the modified nitrile rubber is replaced by a commercially available carboxyl-terminated nitrile rubber, and the other conditions remain unchanged.

[0094] Comparative Example 2: taking Example 1 as a comparison, the hyperbranched polyester grafted montmorillonite is replaced by montmorillonite, and the other conditions remain unchanged.

[0095] Comparative Example 3: taking Example 1 as a comparison, the modified nitrile rubber is replaced by a commercially available carboxyl-terminated nitrile rubber, and the hyperbranched polyester grafted montmorillonite is replaced by montmorillonite, and the other conditions remain unchanged.

[0096] Experiment: the regenerated polyester material obtained in the examples and comparative examples is taken to detect various properties thereof.

[0097] Mechanical property test: refer to GB / T 1040.1-2025 to test the tensile strength and elongation at break of the recycled polyester material, to characterize the mechanical property thereof;

[0098] Antistatic property: refer to GB / T40719-2021 to test the surface resistance of the recycled polyester material, to characterize the antistatic property thereof;

[0099]

[0100] According to the data in the above table, the following conclusions can be drawn:

[0101] Compared with Example 1, the modified nitrile rubber in Comparative Example 1 is replaced by a commercially available carboxyl-terminated nitrile rubber, and the elongation at break of the obtained recycled polyester material decreases more obviously. The reason is that the polycaprolactone in the modified nitrile rubber in the application has excellent ductility and high elongation at break, and synergizes with the nitrile rubber to further improve the elongation at break of the recycled polyester material.

[0102] Compared with Example 1, the hyperbranched polyester grafted montmorillonite in Comparative Example 2 is replaced by montmorillonite, and the tensile strength and antistatic property of the obtained recycled polyester material decrease. The reason is that the quaternary ammonium amino polysiloxane is used in the application to expand the interlayer spacing of the montmorillonite, which is more prone to exfoliate into single layers in the matrix, thereby enhancing the mechanical properties of the material. The quaternary ammonium salt has good antistatic property, and synergizes with the siloxane to impart good lubricity and antistatic property to the recycled polyester material.

[0103] Compared with Example 1, the modified nitrile rubber in Comparative Example 3 is replaced by a commercially available carboxyl-terminated nitrile rubber, and the hyperbranched polyester grafted montmorillonite is replaced by montmorillonite, and the properties of the obtained recycled polyester material all decrease to different degrees.

[0104] In summary, the preparation of the modified nitrile rubber and the hyperbranched polyester grafted montmorillonite in the application can promote the comprehensive improvement of the mechanical properties and antistatic properties of the obtained recycled polyester material.

[0105] It is apparent for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, but can be implemented in other concrete forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present application is defined by the appended claims rather than the above description, and all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application.

Claims

1. A processing method of high tenacity regenerated polyester material for chemical fiber, characterized in that: The method comprises the following steps: ​ The waste polyester material is dried, melt-extruded, mixed with ethylene glycol, and subjected to depolymerization reaction to obtain a depolymerization liquid; the ethylene glycol is distilled under reduced pressure; an epoxy chain extender is added and subjected to heating and stirring reaction; the modified nitrile rubber, the hyperbranched polyester grafted montmorillonite, the accelerator and the antioxidant are added in sequence to perform copolymerization reaction and polycondensation reaction, thereby obtaining the high-toughness regenerated polyester material; The modified nitrile rubber is prepared by the following process: Step 1: mixing the amino-terminated liquid nitrile rubber and the polyepoxy compound, and performing heating reaction under nitrogen atmosphere protection to obtain the epoxy-terminated nitrile rubber; Step 2: mixing the epoxy-terminated nitrile rubber, the tetrabutylammonium hydroxide and the polyhydroxy compound, and performing heating reaction to obtain the hyperbranched nitrile rubber; Step 3: mixing the hyperbranched nitrile rubber, the caprolactone and the tetrabutylammonium hydroxide, and performing heating reaction to obtain the modified nitrile rubber; The hyperbranched polyester grafted montmorillonite is prepared by the following process: S1: mixing the polymethylhydrogen siloxane, the (N,N-dimethyl-3-aminopropyl) trimethoxysilane and the tetramethylammonium hydroxide, and performing heating reaction, rotary evaporation, and reduced pressure distillation to obtain the aminated polysiloxane; S2: mixing the aminated polysiloxane and the ethyl chloroacetate solution, and performing heating reaction and reduced pressure distillation to obtain the quaternary ammonium aminated polysiloxane; S3: dispersing the montmorillonite in an ethanol aqueous solution, performing ultrasonic dispersion, adding the quaternary ammonium aminated polysiloxane, and performing heating reaction, suction filtration, washing and drying to obtain the modified montmorillonite; S4: dispersing the modified montmorillonite in dimethylbenzene, adding the p-toluenesulfonic acid and 1 / 2 mass fraction of dimethylol propionic acid, and performing heating reflux reaction, then adding the remaining dimethylol propionic acid and continuing to react for 2-4 hours, and performing suction filtration, washing and drying to obtain the hyperbranched polyester grafted montmorillonite.

2. The processing method of high tenacity regenerated polyester material for chemical fiber according to claim 1, characterized in that: The mass ratio of the waste polyester material, the ethylene glycol, the epoxy chain extender, the modified nitrile rubber, the hyperbranched polyester grafted montmorillonite, the accelerator and the antioxidant is 100:(0.5-1.5):(0.5-0.7):(25-45):(10-20):(0.3-0.5):(0.5-1.0).

3. The processing method of high tenacity regenerated polyester material for chemical fiber according to claim 1, characterized in that: In step 1, the mass ratio of the amino-terminated liquid nitrile rubber and the polyepoxy compound is 1:(3-5).

4. The processing method of high tenacity regenerated polyester material for chemical fiber according to claim 1, characterized in that: In step 2, the mass ratio of the epoxy-terminated nitrile rubber, the tetrabutylammonium hydroxide and the polyhydroxy compound is 10:(0.3-0.5):(2-4).

5. The processing method of high tenacity regenerated polyester material for chemical fiber according to claim 1, characterized in that: In step 3, the mass ratio of the hyperbranched nitrile rubber, the caprolactone and the tetrabutylammonium hydroxide is 10:(30-50):(0.01-0.03).

6. The processing method of high tenacity regenerated polyester material for chemical fiber according to claim 1, characterized in that: In S1, the mass ratio of the polymethylhydrogen siloxane, the (N,N-dimethyl-3-aminopropyl) trimethoxysilane and the tetramethylammonium hydroxide is 10:(8-10):(0.01-0.03).

7. The processing method of high tenacity regenerated polyester material for chemical fiber according to claim 1, characterized in that: In S2, the mass ratio of the aminated polysiloxane and the ethyl chloroacetate solution is 10:(4-5).

8. A high tenacity regenerated polyester material for synthetic fiber, characterized by: The processing method is obtained according to any one of claims 1-7.

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