CN113416339B

CN113416339B - Plastic hose and preparation method thereof

Info

Publication number: CN113416339B
Application number: CN202110840279.4A
Authority: CN
Inventors: 杨悦; 程文孝; 王春艳; 孙兰英
Original assignee: Shanghai Shuangshi Plastic Products Co ltd
Current assignee: Shanghai Shuangshi Plastic Products Co ltd
Priority date: 2021-07-24
Filing date: 2021-07-24
Publication date: 2022-10-28
Anticipated expiration: 2041-07-24
Also published as: CN113416339A

Abstract

The invention discloses a plastic hose and a preparation method thereof, and relates to the technical field of plastic hoses. The plastic hose is prepared from the following components in parts by weight: 50-65 parts of polytetrafluoroethylene, 1.5-4 parts of filler, 150-200 parts of fluorine-containing siloxane and 400-600 parts of alkyl lithium/ethylenediamine solution; the preparation method comprises the following steps: the method comprises the following steps of carrying out cold press molding on polytetrafluoroethylene and filler to obtain a cold press blank; sintering and molding the cold-pressed blank to obtain filled plastic; making the filled plastic into a filled plastic pipe; and soaking the filled plastic pipe in an alkyl lithium/ethylenediamine solution, and then soaking the filled plastic pipe in fluorine-containing siloxane to obtain the plastic hose. The plastic hose can be used for cosmetic manufacturing or cosmetic conveying, and has the advantages of good hydrophobicity and low water absorption rate; in addition, the preparation method of the application is beneficial to gathering the fluorine-containing siloxane on the surface of the plastic hose and improving the hydrophobicity of the surface of the plastic hose.

Description

Plastic hose and preparation method thereof

Technical Field

The invention relates to the technical field of plastic hoses, in particular to a plastic hose and a preparation method thereof.

Background

The plastic hose has wide application, large demand and wide market. When the plastic hose is applied to cosmetic manufacturing or cosmetic conveying, the used plastic hose needs to have the performances of safety, no toxicity, high temperature resistance, high strength, high toughness, chemical resistance and the like, and the polytetrafluoroethylene has the performances of excellent high and low temperature resistance, low friction, excellent chemical stability and the like, so that the plastic hose made of the polytetrafluoroethylene can be applied to the fields of cosmetic manufacturing or cosmetic conveying. However, the wear resistance of polytetrafluoroethylene is not good enough, and the wear resistance of polytetrafluoroethylene is generally improved by filling modification.

In the related technology, a polytetrafluoroethylene material filled with glass fibers is disclosed, and the polytetrafluoroethylene material filled with the glass fibers is prepared by blending polytetrafluoroethylene and glass fibers in a weight ratio of 100: 10-30, and then extruding and sintering the mixture.

In view of the above-mentioned related art, the inventors of the present invention have considered that the above-mentioned polytetrafluoroethylene material has a problem of high water absorption, and a plastic hose made of such polytetrafluoroethylene material is liable to adversely affect the quality of cosmetics when it is in contact with the cosmetics for a long period of time.

Disclosure of Invention

In order to solve the problem that a plastic hose made of polytetrafluoroethylene is high in water absorption rate, the application provides the plastic hose and the preparation method thereof.

In a first aspect, the present application provides a plastic hose, which adopts the following technical scheme:

a plastic hose is prepared from the following components in parts by weight: 50-65 parts of polytetrafluoroethylene, 1.5-4 parts of filler, 150-200 parts of fluorine-containing siloxane and 400-600 parts of alkyl lithium/ethylenediamine solution.

By adopting the technical scheme, the polytetrafluoroethylene and the filler can be used for preparing the plastic hose with good wear resistance, the polytetrafluoroethylene contains carbon-fluorine bonds, the polytetrafluoroethylene is placed in an alkyl lithium/ethylenediamine solution, the carbon-fluorine bonds can generate a reduction reaction, the surface of the polytetrafluoroethylene can be activated, so that the fluorine-containing siloxane can be grafted on the surface of the polytetrafluoroethylene, the long molecular chain of the polytetrafluoroethylene grafted by the fluorine-containing siloxane can be intertwined with the ungrafted polytetrafluoroethylene, and the fluorine-containing siloxane is favorably fixed on the surface of the polytetrafluoroethylene;

the fluorine-containing siloxane has lower intermolecular force, can reduce the surface energy and the friction coefficient of the polytetrafluoroethylene, is beneficial to improving the hydrophobicity of the polytetrafluoroethylene, and solves the problem of high water absorption of a plastic hose made of the polytetrafluoroethylene; in addition, the fluorine-containing siloxane grafted on the long molecular chain of the polytetrafluoroethylene and the filling material can form chemical bonds or hydrogen bonds, which is beneficial to improving the compatibility of the polytetrafluoroethylene and the filling material.

Preferably, the composition is prepared from the following components in parts by weight: 55-60 parts of polytetrafluoroethylene, 2.5-3 parts of filling material, 170-180 parts of fluorine-containing siloxane and 480-520 parts of alkyl lithium/ethylenediamine solution.

By adopting the technical scheme, the prepared plastic hose has better hydrophobicity at the ratio of the components, and the problem of high water absorption of the plastic hose made of polytetrafluoroethylene can be further improved.

Preferably, the filler is one of glass fiber, carbon fiber and polyarylsulfone.

By adopting the technical scheme, the glass fiber, the carbon fiber and the polyarylsulfone can enhance the wear resistance of the polytetrafluoroethylene, the carbon fiber can also reduce the water absorption of the polytetrafluoroethylene, and the polyarylsulfone can introduce the fluorine-containing siloxane into a polyarylsulfone main chain in a chemical copolymerization mode to further enhance the hydrophobic property of the plastic hose.

Preferably, the fluorine-containing siloxane is trifluoropropyl-containing siloxane.

By adopting the technical scheme, the trifluoropropyl-containing siloxane has a siloxane bond on the main chain, methyl and trifluoropropyl on the side chain, and a fluorine atom on the side chain can shield the siloxane bond, so that the trifluoropropyl-containing siloxane has stronger chemical resistance, and the chemical resistance of the plastic hose can be enhanced.

Preferably, the alkyllithium/ethylenediamine solution is made from t-butyllithium and ethylenediamine in a molar ratio of 1 (0.8-1.2).

By adopting the technical scheme, in the solution of tert-butyl lithium and ethylenediamine in the proportion, the reduction reaction rate on the surface of the polytetrafluoroethylene can be prevented from being too high, and the formation of a carbonaceous layer on the surface of the polytetrafluoroethylene can be reduced.

Preferably, the polytetrafluoroethylene is expanded polytetrafluoroethylene.

By adopting the technical scheme, the expanded polytetrafluoroethylene has a large number of fine fibrils and microporous structures, so that the high temperature resistance, the chemical stability and the high toughness of the polytetrafluoroethylene are kept, the polytetrafluoroethylene is endowed with softness, and the improvement of the flexibility of the plastic hose is facilitated.

In a second aspect, the present application provides a method for manufacturing a plastic hose, which adopts the following technical scheme: a preparation method of a plastic hose comprises the following steps:

s1, uniformly mixing polytetrafluoroethylene and fillers according to a ratio, and performing cold press molding to obtain a cold press blank;

s2, sintering and forming the cold-pressed blank, wherein the sintering temperature is increased to 365-385 ℃ at the heating rate of 100 ℃/h, sintering is carried out for 1.6-2.2h at constant temperature, and the filled plastic is obtained after cooling;

s3, manufacturing the filled plastic into a filled plastic pipe;

and S4, soaking the filled plastic pipe in an alkyl lithium/ethylenediamine solution for 0.4-0.6h at 0 ℃, then soaking the filled plastic pipe in fluorine-containing siloxane for 7-9h at 70 ℃ to obtain the plastic hose.

By adopting the technical scheme, the polytetrafluoroethylene is mixed with the filler, so that the filler is favorably dispersed in the polytetrafluoroethylene; after the filling plastic is made into the filling plastic pipe, the filling plastic pipe is grafted, which is beneficial to the gathering of the fluorine-containing siloxane on the surface of the plastic hose and the improvement of the hydrophobicity of the surface of the plastic hose.

Preferably, in the step S3, the filled plastic is unidirectionally stretched by a stretching method to prepare expanded polytetrafluoroethylene, and then is prepared into the filled plastic tube.

By adopting the technical scheme, the expanded polytetrafluoroethylene prepared from the filled plastic is beneficial to improving the flexibility of the filled plastic pipe, so that the finally prepared plastic hose has better flexibility.

In summary, the present application has the following beneficial effects:

1. because the fluorine-containing siloxane and the alkyl lithium/ethylenediamine solution are adopted, the alkyl lithium/ethylenediamine solution can activate the surface of the polytetrafluoroethylene, so that the fluorine-containing siloxane can be grafted on the surface of the polytetrafluoroethylene, the hydrophobicity of the polytetrafluoroethylene can be improved, and the problem of high water absorption of a plastic hose made of the polytetrafluoroethylene is solved;

2. trifluoropropyl siloxane is preferably used in the application, which can enhance the chemical resistance of the plastic hose;

3. according to the method, the polytetrafluoroethylene and the filler are mixed firstly, so that the filler is favorably dispersed in the polytetrafluoroethylene, the filled plastic is made into the filled plastic pipe firstly, and then the filled plastic pipe is grafted, so that the fluorine-containing siloxane is favorably gathered on the surface of the plastic hose, and the hydrophobicity of the surface of the plastic hose is favorably improved.

Detailed Description

The present application will be described in further detail with reference to examples.

The starting materials used in the examples of the present application are commercially available except as specifically indicated. Wherein the ethylene diamine is industrial grade ethylene diamine from Aite (Shandong) New materials, the sec-butyl lithium is from Shanghai Kaiser chemical Co., ltd, the product number is 598-30-1, the tert-butyl lithium is from Shanghai Kaiser chemical Co., ltd, the product number is 594-19-4, the polytetrafluoroethylene is from DuPont, the product number is 6C, the glass fiber is glass fiber powder from Wuhe Weijia composite Co., ltd, the length-diameter ratio is 13, the carbon fiber is carbon fiber powder from oil antistatic plastics technology Co., ltd, the fineness is 30-1000 mesh, the hydroxyl-terminated fluorine-containing polyester polysiloxane is from Anhui Aita silicone oil Co., ltd, the product number is OTA3375F, the trifluoropropylsiloxane is 3,3,3-trifluoropropyltrimethoxysilane from Wulanai white medicine Co., ltd, the product number is 680001.

Preparation of an alkyllithium/ethylenediamine solution

Preparation examples 1 to 4

As shown in Table I, the main difference between the preparation examples 1 to 4 is the different ratios of the raw materials.

The following description will be made by taking preparation example 1 as an example.

Adding alkyl lithium and ethylenediamine into a stirrer, and stirring for 15min under the condition of 240r/min to obtain an alkyl lithium/ethylenediamine solution.

Table a raw material compounding ratio table of preparation examples 1 to 4

Examples

Examples 1 to 5

As shown in Table I, examples 1-5 differ mainly in the ratios of the raw materials.

A plastic hose is prepared according to the following steps:

s1, according to the proportion, after polytetrafluoroethylene is crushed into powder with the particle size of 25 microns, the powder and filler are added into a mixer together, the mixture is stirred and mixed for 3min at the rotating speed of 8000r/min, the mixed material is placed into a circular mold, and cold press molding is carried out under the pressure of 34.5MPa, so as to obtain a cold press blank;

s2, placing the cold-pressed blank into a high-temperature furnace for sintering and forming, wherein the sintering temperature is increased to 375 ℃ at a heating rate of 100 ℃/h, then sintering at a constant temperature for 2h, taking out the sintered material, and naturally cooling to room temperature at room temperature to obtain filled plastic;

s3, adding the filled plastic into a vertical pushing press, and pushing at a material cavity temperature of 50 ℃ and a neck mold temperature of 60 ℃ to prepare a filled plastic pipe;

s4, soaking the filled plastic pipe in a container containing an alkyl lithium/ethylenediamine solution, submerging the alkyl lithium/ethylenediamine solution in the filled plastic pipe, soaking at the temperature of 0 ℃ for 0.5h, taking out the filled plastic pipe, placing the filled plastic pipe in the container containing fluorine-containing siloxane, submerging the filled plastic pipe in the fluorine-containing siloxane, soaking at the temperature of 70 ℃ for 8h, taking out the soaked pipe, and obtaining a plastic hose;

the filler in this example was glass fiber with aspect ratio of 13, the alkyllithium/ethylenediamine solution was the alkyllithium/ethylenediamine solution prepared in preparation example 1, and the fluorine-containing siloxane was trifluoropropylsiloxane.

TABLE II raw material proportioning tables for examples 1-5

Examples 6 to 11

As shown in Table three, the difference from example 5 is that examples 6 to 11 differ mainly in the raw materials.

TABLE III raw materials proportioning tables for examples 6-12

Example 12

The difference between the embodiment and the embodiment 5 is that in the step S3, the filled plastic is firstly pressed into a blank body with the same shape as the film cavity of the pushing press, the blank body is put into the film cavity of the pushing press to be pushed, a bar is obtained at the pushing opening, and the bar is rolled by a roller to prepare a strip with required width and thickness;

heating and drying the belt material to obtain a polytetrafluoroethylene-based film, rapidly stretching the polytetrafluoroethylene-based film, controlling the stretching temperature to be between the glass transition temperature of 115 ℃ and the melting point of 327 ℃ of polytetrafluoroethylene, putting the expanded polytetrafluoroethylene into a mold at 330 ℃, heating and pressurizing the expanded polytetrafluoroethylene to be integrated, and cooling the integrated polytetrafluoroethylene to obtain expanded polytetrafluoroethylene; and then putting the expanded polytetrafluoroethylene into a vertical pushing press, and pushing at the temperature of a material cavity of 50 ℃ and the temperature of a neck mold of 60 ℃ to prepare the filling plastic pipe.

Comparative example

Comparative example 1

The polytetrafluoroethylene material filled with glass fibers provided by the comparative example was prepared by the following steps:

1) Blending polytetrafluoroethylene and glass fiber as a filling material in a mixer at a weight ratio of 100: 15 for 2 minutes to prepare a blend stock;

2) Placing the mixed material into the inner space of a common die consisting of an outer die, an upper pressing die and a lower pressing die, maintaining the pressure for 6min at the pressure of 12Mpa and the pressurizing rate of 15mm/min to complete the press forming, and then releasing the pressure and demolding to obtain a semi-finished blank;

3) Putting the semi-finished blank into a sintering furnace, firstly heating at the speed of 50 ℃/h, and preserving heat for 5 hours when the temperature is raised to 300 ℃; then heating up at the rate of 30 ℃/h, and preserving heat for 6 hours when the temperature is raised to 330 ℃; then heating up at the speed of 20 ℃/h, and preserving heat for 8 hours when the temperature is raised to 380 ℃; then cooling at the speed of 20 ℃/h, and preserving heat for 7 hours when the temperature is reduced to 330 ℃; cooling at the speed of 30 ℃/h, and preserving heat for 6 hours when the temperature is reduced to 300 ℃; finally, cooling to 250 ℃ at the speed of 50 ℃/h, and naturally cooling to room temperature to obtain the polytetrafluoroethylene material filled with the glass fiber.

Comparative examples 2 to 3

As shown in Table IV, the differences from preparation example 1 are that the raw material ratios of comparative examples 2 to 3 are different.

TABLE IV raw material proportioning tables for comparative examples 2-3

Comparative example 4

This comparative example differs from preparation 1 in that the alkyllithium/ethylenediamine solution was not included.

Comparative example 5

This comparative example differs from preparation example 1 in that no fluorine-containing siloxane was contained.

Performance test

The pipe samples prepared in preparations 1 to 12 of the present application and comparative examples 1 to 5 were subjected to a performance test. Wherein, the flexibility of the sample is detected according to the tensile strength and the elongation at break of the sample tested by QB/T4877-2015 Teflon tube; testing the mass abrasion loss of the sample according to QB/T5101-2017 plastic pipe abrasion resistance test method to detect the abrasion resistance of the sample; and (3) detecting the water contact angle of the sample according to GB/T26490-2011 'detection method for the super-amphiphobic property of the nano material', so as to detect the hydrophobic property of the sample.

The test results are shown in table five.

Table five test data tables for pipe samples of preparation examples 1-12 and comparative examples 1-5

Combining examples 1-5 with comparative example 1 and combining Table V, it can be seen that the pipe samples prepared in examples 1-5 all had lower tensile strength and higher elongation at break than the pipe samples prepared under the conditions of comparative example 1, indicating that the pipe samples prepared under the conditions of examples 1-5 all had better flexibility; the pipe samples prepared in examples 1 to 5 all have larger water contact angles and are more than 90 degrees, which shows that the pipe samples prepared under the conditions of examples 1 to 5 all have better hydrophobic property and improve the problem of high water absorption of the plastic hose; the samples of pipes prepared in examples 1-5 all had lower mass wear, indicating that the samples of pipes prepared under the conditions of examples 1-5 all had better wear resistance.

Combining examples 1-5 and comparative examples 2-3 with Table V, it can be seen that the pipe samples prepared under the conditions of examples 1-5 all had lower tensile strength and higher elongation at break than the pipe samples prepared under the conditions of comparative examples 2-3, indicating that the pipe samples prepared under the conditions of examples 1-5 all had better flexibility; the pipe samples prepared under the conditions of examples 1-5 had larger water contact angles and smaller mass abrasion loss, which indicates that the pipe samples prepared under the conditions of examples 1-5 had better hydrophobicity and abrasion resistance.

Combining example 5 and comparative examples 4-5 with table five, it can be seen that the pipe samples prepared under the conditions of comparative examples 4-5 have lower water contact angles and higher mass abrasion loss than the pipe samples prepared under the conditions of example 5, indicating that the pipe samples prepared under the conditions of the alkyllithium/ethylenediamine solution and the fluorosilicone have better hydrophobic properties.

As can be seen by combining examples 5-7 with Table V, the pipe samples prepared under the conditions of examples 5-7 all had better flexibility, which indicates that glass fiber, carbon fiber and polyarylsulfone all contribute to improving the flexibility of the plastic hose; the pipe samples prepared under the conditions of examples 6-7 all had larger water contact angles than the pipe samples prepared under the conditions of example 5, indicating that both carbon fiber and polyarylsulfone contribute to further enhancing the hydrophobicity of the plastic hose.

It can be seen by combining examples 5 and 8 and table five that the pipe samples prepared under the conditions of examples 5 and 8 have better hydrophobicity, which indicates that the hydroxyl-terminated fluorine-containing polyester polysiloxane and the trifluoropropyl siloxane both contribute to improving the hydrophobicity of the reinforced plastic hose.

It can be seen from the combination of example 5 and examples 9-11 and from Table five that the pipe samples prepared under the conditions of examples 5 and 9-11 all have better hydrophobicity, which indicates that the alkyllithium/ethylenediamine solutions prepared under the conditions of preparation examples 1-4 all contribute to improving the hydrophobicity of the reinforced plastic hose.

Combining example 5 and example 12 with table five, it can be seen that the pipe sample prepared under the conditions of example 5 has lower tensile strength and greater elongation at break than the pipe sample prepared under the conditions of example 12, indicating that expanded polytetrafluoroethylene contributes to improved flexibility of the reinforced plastic hose.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.

Claims

1. The plastic hose is characterized by being prepared from the following components in parts by weight: 50-65 parts of polytetrafluoroethylene, 1.5-4 parts of a filler, 150-200 parts of fluorine-containing siloxane and 400-600 parts of an alkyl lithium/ethylenediamine solution, wherein the fluorine-containing siloxane is trifluoropropyl siloxane, and the filler is polyarylsulfone; the preparation method of the plastic hose comprises the following steps:

s2, sintering and forming the cold-pressed blank, wherein the sintering temperature is increased to 365-385 ℃ at the heating rate of 100 ℃/h, sintering is carried out for 1.6-2.2h at constant temperature, and cooling is carried out to obtain filling plastics;

s3, manufacturing the filled plastic into a filled plastic pipe;

and S4, soaking the filled plastic pipe in an alkyl lithium/ethylenediamine solution for 0.4-0.6h at 0 ℃, soaking the filled plastic pipe in fluorine-containing siloxane for 7-9h at 70 ℃ to obtain the plastic hose.

2. The plastic hose of claim 1, wherein: the composition is prepared from the following components in parts by weight: 55-60 parts of polytetrafluoroethylene, 2.5-3 parts of filling material, 170-180 parts of fluorine-containing siloxane and 480-520 parts of alkyl lithium/ethylenediamine solution.

3. The plastic hose of claim 1, wherein: the alkyl lithium/ethylenediamine solution is prepared from tert-butyl lithium and ethylenediamine, and the molar ratio of the tert-butyl lithium to the ethylenediamine is 1 (0.8-1.2).

4. The plastic hose of claim 1, wherein: the polytetrafluoroethylene is expanded polytetrafluoroethylene.

5. The plastic hose of claim 1, wherein: and in the step S3, the filled plastic is subjected to unidirectional stretching by adopting a stretching method to prepare expanded polytetrafluoroethylene, and then the expanded polytetrafluoroethylene is prepared into a filled plastic pipe.