High-strength anti-aging composite plastic hose and preparation method thereof

Abstract

The invention relates to the technical field of polyethylene pipes, and discloses a high-strength anti-aging composite plastic hose and a preparation method thereof.The high-strength anti-aging composite plastic hose is prepared from, by weight, 100 parts of polyethylene resin and 0.5-3 parts of hindered phenol antioxidant modified graphene; after the surface of the graphene oxide is organically modified, the dispersity becomes good, and the graphene oxide contains long-chain alkane similar to a polyethylene chain segment, so that the compatibility between the graphene and the polyethylene resin is further improved, and the tensile strength and the elongation at break of the material are remarkably enhanced. The modified graphene is uniformly dispersed in a polyethylene matrix, and a continuous conductive path can be formed, so that the volume resistivity is reduced, and the antistatic performance of the material is improved. The surface of the modified graphene is grafted with a hindered phenol structure of di-tert-butylphenol, so that the thermo-oxidative aging resistance of polyethylene can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of polyethylene pipes, in particular to a high-strength aging-resistant composite plastic hose and a preparation method thereof. Background Art

[0002] Polyethylene resin is odorless, non-toxic, colorless and transparent, has excellent low temperature resistance and corrosion resistance, and is widely used in hose containers, pipes and pipelines, wires and cables, electronic appliances, etc. Traditional polyethylene pipes and other products have problems such as high resistivity, poor antistatic performance, low mechanical strength, and poor thermal oxygen aging resistance.

[0003] Adding antioxidants such as hindered phenols to polyethylene resin can improve its aging resistance and other properties. As a nanomaterial with excellent performance, graphene oxide has important applications in materials such as polyethylene, polystyrene, acrylic resin, and epoxy resin. Improving the dispersibility of graphene and improving its compatibility with the resin matrix are research hotspots. Chinese patent CN109651649B discloses a graphene-based antioxidant and its preparation method and application. The antioxidant is grafted onto the obtained carboxyl-activated graphene oxide to obtain a graphene-based antioxidant, which can improve the thermal oxygen stability of polyolefin materials. However, the patent does not significantly improve the compatibility between graphene and materials such as polyethylene, which is not conducive to improving the tensile and other mechanical properties of the material. Summary of the invention

[0004] The invention solves the problem that the strength, aging resistance, antistatic properties and the like of polyethylene and its pipes are relatively poor.

[0005] The technical solution of the present invention is a high-strength aging-resistant composite plastic hose and a preparation method thereof, which comprises 100 parts of polyethylene resin and 0.5-3 parts of hindered phenol antioxidant modified graphene in parts by weight.

[0006] The preparation method is as follows: polyethylene resin and hindered phenol antioxidant modified graphene are added into an extruder for melt blending, the temperature of sections 1-6 is 150-185°C, the screw speed is 60-100r / min, extrusion molding is performed to obtain a high-strength aging-resistant composite plastic hose.

[0007] Further, the preparation method of hindered phenol antioxidant modified graphene is:

[0008] (1) Add 100-130 parts by weight of thionyl chloride and 1 part of graphene oxide to a reaction vessel equipped with a condenser reflux tube, disperse by ultrasonic, react at 60-70° C. in a nitrogen atmosphere for 18-24 hours, distill under reduced pressure, and dry to obtain graphene chloride.

[0009] (2) Add solvent and chlorinated graphene to a reaction vessel, disperse by ultrasonication, add triethylamine and fatty acid ester hindered phenol, react at 15-20°C for 1-2h, then at 30-45°C for 24-36h, distill under reduced pressure, wash with chloroform, water, and ethanol in turn, and dry to obtain hindered phenol antioxidant modified graphene. The reaction formula is as follows:

[0010]

[0011] Furthermore, the solvent is dichloromethane, chloroform or toluene.

[0012] Furthermore, by weight, the amount of the acyl chloride graphene is 100 parts, the amount of triethylamine is 25-70 parts, and the amount of fatty acid ester hindered phenol is 120-300 parts.

[0013] Furthermore, the preparation method of fatty acid ester hindered phenol is as follows: toluene, 100 parts of 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid, 76-84 parts of alkyl glycidyl ether, and 2-2.5 parts of tetrabutylammonium bromide are added to a reaction vessel provided with a condenser reflux tube by weight, stirred and reacted at 100-110° C. for 6-8 hours, filtered, the filtrate is distilled under reduced pressure, washed with ethanol, and the product is recrystallized in chloroform to obtain fatty acid ester hindered phenol. The reaction formula is as follows:

[0014]

[0015] The beneficial technical effect of the present invention is as follows: the present invention performs a ring-opening reaction on 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid and alkyl glycidyl ether to obtain a fatty acid ester hindered phenol, and the secondary hydroxyl group with less steric hindrance reacts with the acyl chloride group of acyl chloride graphene to obtain hindered phenol antioxidant modified graphene, which is finally blended with polyethylene resin and molded to obtain a high-strength aging-resistant composite plastic hose material. After the surface of graphene oxide is organically modified, the dispersibility becomes better, and it contains long-chain alkanes similar to polyethylene segments. At the same time, during the blending process, the long-chain alkanes of graphene and polyethylene molecular chains undergo physical chain entanglement, which further improves the compatibility and interfacial force between graphene and polyethylene resin, and significantly enhances the tensile strength and elongation at break of the material.

[0016] The modified graphene of the present invention is uniformly dispersed in the polyethylene matrix to form a continuous conductive path, thereby reducing the volume resistivity and being beneficial to improving the antistatic performance of the material.

[0017] The modified graphene surface of the present invention is grafted with the hindered phenol structure of di-tert-butylphenol, which can reduce the free radicals generated by the thermal oxidation of polyethylene and inhibit the free radical chain reaction, thereby improving the thermal oxidation aging resistance of polyethylene. After high-temperature thermal oxidation aging, the polyethylene material still has high tensile strength and elongation at break. DETAILED DESCRIPTION

[0018] The following examples are further listed to illustrate the present invention in detail. It should also be understood that the following examples are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the principles described in the present invention belong to the scope of protection of the present invention.

[0019] The following polyethylene resin, brand 7149U, Shandong Ousheng Chemical Co., Ltd. Graphene oxide, thickness between 0.6-1.2nm, Guangzhou Hongwu Material Technology Co., Ltd.

[0020] Embodiment 1:

[0021] (1) Add 100 g of thionyl chloride and 1 g of graphene oxide to a reaction vessel equipped with a condenser reflux tube, disperse by ultrasonication, react at 70° C. for 18 h in a nitrogen atmosphere, distill under reduced pressure, and dry to obtain graphene chloride.

[0022] (2) Add 50 mL of toluene, 4 g of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid, 3.36 g of octadecyl glycidyl ether, and 0.1 g of tetrabutylammonium bromide to a reaction vessel equipped with a condenser reflux tube, stir and react at 100° C. for 6 h, filter, distill the filtrate under reduced pressure, wash with ethanol, and recrystallize the product in chloroform to obtain a fatty acid ester hindered phenol.

[0023] (3) Add 150 mL of chloroform and 2 g of chlorinated graphene into a reaction container, disperse by ultrasonic, add 0.5 g of triethylamine and 2.4 g of fatty acid ester hindered phenol, react at 15 ° C for 2 h, then react at 40 ° C for 24 h, distill under reduced pressure, wash with chloroform, water, and ethanol in turn, and dry to obtain hindered phenol antioxidant modified graphene.

[0024] (4) Add 10 kg of polyethylene resin and 50 g of hindered phenol antioxidant modified graphene into an extruder for melt blending. The temperatures of sections 1-6 are 150° C., 160° C., 175° C., 175° C., 185° C., and 180° C. The screw speed is 100 r / min, and extrusion molding is performed to obtain a high-strength, aging-resistant composite plastic hose.

[0025] Embodiment 2:

[0026] (1) Add 130 g of thionyl chloride and 1 g of graphene oxide to a reaction vessel equipped with a condenser reflux tube, disperse by ultrasonication, react at 60° C. in a nitrogen atmosphere for 24 h, distill under reduced pressure, and dry to obtain graphene chloride.

[0027] (2) Add 40 mL of toluene, 4 g of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid, 3.04 g of hexadecyl glycidyl ether, and 0.08 g of tetrabutylammonium bromide to a reaction vessel equipped with a condenser reflux tube, stir and react at 110° C. for 8 h, filter, distill the filtrate under reduced pressure, wash with ethanol, and recrystallize the product in chloroform to obtain a fatty acid ester hindered phenol.

[0028] (3) Add 200 mL of dichloromethane and 2 g of chlorinated graphene into a reaction container, disperse by ultrasonication, add 0.8 g of triethylamine and 4 g of fatty acid ester hindered phenol, react at 20° C. for 1 h, then at 30° C. for 36 h, distill under reduced pressure, wash with chloroform, water, and ethanol in turn, and dry to obtain hindered phenol antioxidant modified graphene.

[0029] (4) Add 10 kg of polyethylene resin and 150 g of hindered phenol antioxidant modified graphene into an extruder for melt blending. The temperatures of sections 1-6 are 150° C., 160° C., 175° C., 175° C., 185° C., and 180° C. The screw speed is 60 r / min, and extrusion molding is performed to obtain a high-strength, aging-resistant composite plastic hose.

[0030] Embodiment 3:

[0031] (1) 200 mL of toluene and 2 g of chlorinated graphene (prepared in Example 1) were added to a reaction container, and ultrasonic dispersion was performed. 1.4 g of triethylamine and 6 g of fatty acid ester hindered phenol (prepared in Example 1) were added, and the mixture was reacted at 20° C. for 1 h, and then at 45° C. for 36 h. The mixture was distilled under reduced pressure, washed with chloroform, water, and ethanol in sequence, and dried to obtain hindered phenol antioxidant modified graphene.

[0032] (2) Add 10 kg of polyethylene resin and 300 g of hindered phenol antioxidant modified graphene into an extruder for melt blending. The temperatures of sections 1-6 are 150° C., 160° C., 175° C., 175° C., 185° C., and 180° C. The screw speed is 100 r / min, and extrusion molding is performed to obtain a high-strength, aging-resistant composite plastic hose.

[0033] Comparative Example 1:

[0034] (1) 10 kg of polyethylene resin was added to an extruder, the temperatures of sections 1-6 were 150° C., 160° C., 175° C., 175° C., 185° C., and 180° C., the screw speed was 100 r / min, and extrusion molding was performed to obtain a plastic hose.

[0035] Comparative Example 2:

[0036] (1) 10 kg of polyethylene resin and 50 g of graphene oxide were added to an extruder for melt blending. The temperatures of sections 1-6 were 150° C., 160° C., 175° C., 175° C., 185° C., and 180° C. The screw speed was 100 r / min, and extrusion molding was performed to obtain a composite plastic hose.

[0037] Comparative Example 3:

[0038] (1) Add 150 mL of chloroform and 2 g of graphene chloride to a reaction vessel, disperse by ultrasonication, add 0.5 g of triethylamine and 2.4 g of 3,5-di-tert-butyl-4-hydroxybenzyl alcohol (structural formula CAS No. 88-26-6), first react at 15°C for 2h, then react at 40°C for 24h, distill under reduced pressure, wash with chloroform, water, and ethanol in sequence, and dry to obtain hindered phenol antioxidant modified graphene.

[0039] (2) Add 10 kg of polyethylene resin and 50 g of hindered phenol antioxidant modified graphene into an extruder for melt blending. The temperatures of sections 1-6 are 150° C., 160° C., 175° C., 175° C., 185° C., and 180° C. The screw speed is 100 r / min, and extrusion molding is performed to obtain a composite plastic hose.

[0040] Comparative Example 4:

[0041] (1) Add 150 mL of chloroform and 2 g of graphene chloride to a reaction vessel, disperse by ultrasonication, add 0.5 g of triethylamine and 2.4 g of octadecyl alcohol (structural formula HO-C 18 H 37 , CAS No. 112-92-5), first react at 15°C for 2h, then react at 40°C for 24h, distill under reduced pressure, wash with chloroform, water, and ethanol in sequence, and dry to obtain octadecyl alcohol-modified graphene.

[0042] (2) 10 kg of polyethylene resin and 50 g of octadecyl alcohol-modified graphene were added to an extruder for melt blending. The temperatures of sections 1-6 were 150° C., 160° C., 175° C., 175° C., 185° C., and 180° C. The screw speed was 100 r / min, and extrusion molding was performed to obtain a composite plastic hose.

[0043] Performance test, prepare injection molding splines for testing, take Example 1 as an example to prepare the spline process: keep the process of Example 1 unchanged, only replace the step of extrusion molding of Example 1 to obtain a hose with extrusion (extrusion conditions are the same as Example 1), granulation and injection molding by injection molding machine (injection molding machine 1-3 section temperature is 210℃, 220℃, 225℃) to inject into the spline step, and then test the spline. The specific steps are: add 10kg polyethylene resin and 50g hindered phenol antioxidant modified graphene into the extruder for melt blending, the temperature of 1-6 sections is 150℃, 160℃, 175℃, 175℃, 185℃, 180℃, the screw speed is 100r / min, extrusion granulation, injection molding into standard splines by injection molding machine, the temperature of 1-3 sections of the injection molding machine is 210℃, 220℃, 225℃.

[0044] Then, a high resistance meter was used to read the volume resistance and volume resistivity of each sample.

[0045] Table 1 Volume resistance test

[0046]

[0047]

[0048] The tensile properties of the specimens were tested according to the national standard GB / T 1040.1-2018. The specimens were placed in a blast drying oven, thermally aged at 100°C for 168 hours, cooled at room temperature, and then the tensile properties were tested.

[0049] Table 2 Tensile properties test

[0050]

[0051] The polyethylene material of Comparative Example 1 has a large volume resistivity and poor antistatic performance. At the same time, the tensile strength and elongation at break are low. After thermal oxidative aging treatment, the tensile strength and elongation at break decrease significantly, the retention rate is low, and the aging resistance is poor.

[0052] The polyethylene material of embodiment 1-3 is added with hindered phenol antioxidant modified graphene, and the surface of graphene oxide is organically modified, and the dispersibility becomes better, and contains long-chain alkanes similar to polyethylene segments, and in the blending process, the long-chain alkanes of graphene and the polyethylene molecular chain are physically entangled, and the compatibility and interfacial force between graphene and polyethylene resin are further improved, thereby significantly improving the compatibility between graphene and polyethylene resin, enhancing the tensile strength and elongation at break of the material, and graphene is uniformly dispersed in the polyethylene matrix at the same time, and a continuous conductive path can be formed, thereby reducing the volume resistivity, which is conducive to improving the antistatic properties of the material. And the hindered phenol structure of di-tert-butylphenol is grafted on the graphene surface, which can reduce the free radicals generated by the thermal oxidation of polyethylene, inhibit the free radical chain reaction, thereby improving the thermal oxidation aging resistance of polyethylene. After high-temperature thermal oxidation aging, the polyethylene material still has very high tensile strength and elongation at break, and the retention rate is high.

[0053] Compared with Example 1, Comparative Example 2 only adds graphene oxide, which is easy to agglomerate, and has poor compatibility with polyethylene resin, poor dispersibility, resulting in low tensile strength and elongation at break of the material, while the volume resistivity is higher than that of Example 1, poor antistatic performance, and after high temperature thermal oxidation aging, the tensile strength and elongation at break of the polyethylene material decrease greatly, and the aging resistance is poor. Comparative Example 3 uses the hydroxymethyl of 3,5-di-tert-butyl-4-hydroxybenzyl alcohol to react with the acyl chloride group of acyl chloride graphene to introduce the hindered phenol structure into the graphene surface. After the surface of graphene oxide is organically modified, the dispersibility becomes better, which is conducive to reducing the volume resistivity of polyethylene, but it does not contain long-chain alkanes, resulting in the compatibility of graphene with polyethylene resin is lower than that of Example 1, and the tensile strength and elongation at break of the material are low. Example 4 utilizes the hydroxyl group of octadecyl alcohol to react with the acyl chloride group of acyl chloride graphene to introduce long-chain alkanes on the graphene surface, thereby improving the compatibility between graphene and polyethylene resin, which is beneficial to improving the tensile strength and elongation at break of the material, reducing the volume resistivity, and improving the antistatic properties. However, graphene does not contain a hindered phenol structure, resulting in poor aging resistance of the polyethylene material. After high-temperature thermal oxidation aging, the tensile strength and elongation at break of the material decrease significantly.

[0054] The above is only an embodiment of the present invention, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A high-strength, aging-resistant composite plastic hose, characterized in that: The high-strength, aging-resistant composite plastic hose comprises, by weight, 100 parts of polyethylene resin and 0.5-3 parts of hindered phenol antioxidant-modified graphene; The preparation method of the hindered phenol antioxidant modified graphene is as follows: adding a solvent and chlorinated graphene into a reaction container, performing ultrasonic dispersion, adding triethylamine and fatty acid ester hindered phenol, performing reduced pressure distillation after the reaction, washing with chloroform, water and ethanol in sequence, and drying to obtain the hindered phenol antioxidant modified graphene; The structural formula of the fatty acid ester hindered phenol is: n is any integer between 14 and 18.

2. The high-strength, aging-resistant composite plastic hose according to claim 1, characterized in that: The solvent is dichloromethane, chloroform or toluene.

3. The high-strength, aging-resistant composite plastic hose according to claim 1, characterized in that: The reaction is first carried out at 15-20°C for 1-2 h and then at 30-45°C for 24-36 h.

4. The high-strength, aging-resistant composite plastic hose according to claim 1, characterized in that: In terms of weight, the usage of the acyl chloride graphene is 100 parts, the usage of triethylamine is 25-70 parts, and the usage of fatty acid ester hindered phenol is 120-300 parts.

5. The high-strength, aging-resistant composite plastic hose according to claim 4, characterized in that: The preparation method of the chlorinated graphene is as follows: by weight, 100-130 parts of thionyl chloride and 1 part of graphene oxide are added into a reaction container, ultrasonically dispersed, reacted at 60-70° C. for 18-24 hours in a nitrogen atmosphere, and distilled under reduced pressure and dried to obtain the chlorinated graphene.

6. The high-strength, aging-resistant composite plastic hose according to claim 4, characterized in that: The preparation method of the fatty acid ester hindered phenol comprises the following steps: adding toluene, 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid, alkyl glycidyl ether and tetrabutylammonium bromide into a reaction container, stirring for reaction and filtering, distilling the filtrate under reduced pressure, washing with ethanol, and recrystallizing the product in chloroform to obtain the fatty acid ester hindered phenol.

7. The high-strength, aging-resistant composite plastic hose according to claim 6, characterized in that: The reaction temperature is 100-110° C. and the reaction time is 6-8 hours.

8. The high-strength, aging-resistant composite plastic hose according to claim 6, characterized in that: In terms of weight, the amount of 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid is 100 parts, the amount of alkyl glycidyl ether is 76-84 parts, and the amount of tetrabutylammonium bromide is 2-2.5 parts; the structural formula of alkyl glycidyl ether is n is any integer between 14 and 18.

9. A method for preparing a high-strength, aging-resistant composite plastic hose according to any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: adding polyethylene resin and hindered phenol antioxidant modified graphene into an extruder for melt blending, setting the temperature of sections 1 to 6 at 150 to 190° C., setting the screw speed at 60 to 100 r / min, and performing extrusion molding to obtain a high-strength aging-resistant composite plastic hose.

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