oil-resistant blended rubber-plastic cable sheath material and preparation method thereof
Technical Field
The invention relates to the technical field of plastic cable sheaths and preparation thereof, in particular to oil-resistant blended rubber-plastic cable sheath materials and a preparation method thereof.
Background
The cable sheath is the indispensable intermediate structure part of cable, plays the effect of protection cable, guarantees the circular telegram safety of cable, lets medium such as copper wire and water, air isolated, avoids appearing the electric leakage phenomenon. Therefore, the sheath of the cable in some environments needs to have excellent oil resistance so as to meet the actual requirement. The traditional rubber-plastic blending system has a complex processing technology and is limited by the heat resistance and oil resistance of the base material, the heat resistance and oil resistance of the blending system are slightly insufficient, and the use requirements of drilling platforms, locomotives and other severe environments are difficult to meet.
Because the cold-resistant and oil-resistant flame-retardant sheath material is often used in severe environmental conditions, such as high temperature, strong ultraviolet irradiation, high ozone concentration, chemical corrosion and the like, the highest temperature can exceed 100 ℃ in some places, if the cable does not meet the requirements, the cable material is fragile and even can decompose the cable sheath layer, all the situations can directly increase the occurrence of fire or casualties of people, and the risk of short circuit of the cable can also increase. The nitrile rubber as the copolymer rubber of butadiene and acrylonitrile has the advantages of excellent oil resistance, aging resistance, wear resistance and the like. And because the nitrile rubber has polar groups in the molecule and has better compatibility with polyvinyl chloride, the blend of the nitrile rubber and the polyvinyl chloride has good mechanical property, and particularly has obvious modification effect on the defects of low impact strength, insufficient elasticity and the like of the polyvinyl chloride. Therefore, the nitrile rubber/polyvinyl chloride blending system is often used as a sheath material for oil-resistant and low-temperature-resistant electric wires and cables.
The nitrile rubber is prepared from butadiene and acrylonitrile by an emulsion polymerization method, is mainly produced by a low-temperature emulsion polymerization method, has excellent oil resistance, higher wear resistance, better heat resistance and strong bonding force, has the defects of poor low-temperature resistance, poor ozone resistance, poor insulating property and slightly lower elasticity, is mainly used for manufacturing oil-resistant rubber products, and is synthetic rubbers prepared by copolymerizing butadiene and acrylonitrile, wherein the nitrile rubber is the synthetic rubber with better oil resistance (especially alkane oil) and aging resistance, the acrylonitrile content (%) in the nitrile rubber is five types including 42-46, 36-41, 31-35, 25-30, 18-24 and the like, the more the acrylonitrile content is, the better the oil resistance is, but the cold resistance is correspondingly reduced, the nitrile rubber can be used in 120 ℃ air or 150 ℃ oil for a long time, and further has good water resistance, air tightness and excellent bonding property, is widely used for manufacturing various oil-resistant rubber products, various gaskets, sleeves, flexible packages, oil-resistant pipes, printing and dyeing cables, aeronautical rubber roll, flexible rubber materials and the like.
The chloroprene rubber has good physical and mechanical properties, oil resistance, heat resistance, flame resistance, sunlight resistance, ozone resistance, acid and alkali resistance and chemical reagent resistance, and has the defects of poor cold resistance and storage stability.
However, the traditional nitrile rubber/polyvinyl chloride blending system is complex in processing technology, a reinforcing agent carbon black is required to be added in , otherwise, the mechanical property is not good, for example, an oil-resistant low-temperature-resistant rubber-plastic composition disclosed in Chinese patent publication CN101353451A and a flame-retardant thermosetting nitrile polyvinyl chloride rubber for wires and cables disclosed in CN102050971A are not good in wear resistance and high temperature resistance of the traditional system, can only meet short-term low-temperature oil resistance and cannot meet the requirement of long-term high-temperature oil immersion performance at 105 ℃.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, provides oil-resistant blended rubber-plastic cable sheath materials and a preparation method thereof, solves the problem that a rubber-plastic sheath in the prior art cannot meet the requirement of long-term high-temperature oil immersion at 105 ℃, and has the advantages of no deformation, no cracking and long service life after long-term use in high-temperature oil.
The purpose of the invention is realized by the following technical scheme:
the preparation method of oil-resistant blended rubber-plastic cable sheath materials is characterized by comprising the following steps:
step , adding the layered mineral into a grinding machine, adding liquid nylon for wetting, grinding for 2-4 hours, continuously adding a stripping propping aid and a coupling agent into the grinding machine, continuously grinding for 2-4 hours, and uniformly mixing to obtain a jelly, namely a layered mineral-nylon blend;
and step two, adding the nitrile rubber and the chloroprene rubber into an internal mixer according to the weight ratio for times of internal mixing, adding an auxiliary agent into the rubber matrix for the second time of internal mixing, adding the layered mineral-nylon blend for the third time of internal mixing, and thinly passing through an open mill to obtain the oil-resistant blended rubber-plastic cable sheath material.
Preferably, the layered minerals are at least of mica powder, talc, montmorillonite, kaolin, illite and graphite.
Preferably, the liquid nylon is a glue solution with the mass concentration of 15% obtained by dissolving nylon in dimethylformamide.
Preferably, the stripping propping aid is at least of sodium dodecyl sulfonate and sodium dodecyl benzene sulfonate.
Preferably, the coupling agent is at least of silane coupling agent, titanate coupling agent, aluminate coupling agent and zirconate coupling agent.
, the layered mineral-nylon blend is prepared from the following raw materials, by weight, 10-20 parts of a layered mineral, 8-15 parts of liquid nylon, 0.5-1 part of a delamination supporting agent, and 0.1-0.3 part of a coupling agent.
, the rotation speed of the grinding in step is 38 r/min.
Preferably, the materials in the second step are banburied according to the parts by weight, 60-100 parts of nitrile rubber, 40-60 parts of chloroprene rubber, 20-40 parts of layered mineral-nylon blend and 5-10 parts of auxiliary agent;
preferably, the auxiliary agent is prepared from the following raw materials in parts by weight: 1-2 parts of an anti-aging agent, 0.5-1.0 part of a vulcanization activator, 3-5 parts of a vulcanization crosslinking agent, 1-2 parts of a plasticizer, 2-4 parts of a dispersing agent, 3-5 parts of a flame retardant and 2-5 parts of a promoter.
, wherein the anti-aging agent is at least of anti-aging agent AW, anti-aging agent RD, anti-aging agent A and anti-aging agent D;
the vulcanization active agent is magnesium stearate;
the vulcanization crosslinking agent is sulfur;
the plasticizer is at least of plasticizer DOP, plasticizer DCP, plasticizer DMP, plasticizer DINP and plasticizer DIDP;
the dispersant is a plastic dispersant EBS;
the accelerator is at least of accelerator DMP-30, accelerator EP-184, accelerator BDMA, accelerator TMTD and accelerator DPG.
The flame retardant consists of the following components in parts by weight: 1-2 parts of red phosphorus, 2-3 parts of ammonium polyphosphate and 1-2 parts of tricresyl phosphate.
And , carrying out the temperature of times of banburying in the second step of the process is 55-65 ℃, and the banburying time is 3-4 min, carrying out the second banburying in the second step of the process is 55-65 ℃, and the banburying time is 5-10 min, and carrying out the third banburying in the second step of the process is 55-65 ℃, and the banburying time is 5-15 min.
The colloid is obtained by dispersing the lamellar mineral in the liquid nylon and grinding the lamellar mineral, and the colloid is subjected to rubber-plastic blending with a rubber matrix, so that the liquid nylon is favorably and uniformly dispersed with the lamellar structure mineral, the nylon has excellent oil resistance, and the dispersed lamellar structure mineral can resist the penetration of oil. The supporting force of the layered structure of the layered mineral is enhanced by adding the delamination supporting agent, and the raw materials are mixed more uniformly by the coupling agent.
The colloid is obtained by dispersing the lamellar mineral in the liquid nylon and grinding the lamellar mineral, and the colloid is subjected to rubber-plastic blending with a rubber matrix, so that the liquid nylon can be favorably uniformly dispersed with the lamellar structure mineral, the nylon has excellent oil resistance, and the dispersed lamellar structure mineral can resist the penetration of oil; the prepared blended rubber-plastic sheath has excellent oil resistance, high temperature resistance, chemical corrosion resistance and aging resistance, and can be used in severe environments such as high-temperature oil immersion and the like for a long time without deformation and cracking; the blended rubber-plastic sheath has the advantages of complete and reliable performance and long service life, and can completely meet the requirements of cable sheaths in specific fields.
The anti-aging agent, the vulcanization activator, the vulcanization cross-linking agent, the plasticizer, the dispersant, the flame retardant and the accelerator are added into the blended rubber-plastic sheath, so that various performances of the blended rubber-plastic sheath are improved, and the blended rubber-plastic sheath is more beneficial to processing and forming so as to be suitable for industrial large-scale production.
The invention relates to a flame retardant which is a functional auxiliary agent for endowing inflammable polymers with flame retardancy, and is mainly designed aiming at the flame retardancy of high polymer materials.
The second purpose of the invention is to provide oil-resistant blended rubber-plastic cable sheath materials prepared by the method.
The invention has the beneficial effects that: the colloid is obtained by dispersing the lamellar mineral in the liquid nylon and grinding the lamellar mineral, and the colloid is subjected to rubber-plastic blending with a rubber matrix, so that the liquid nylon can be favorably uniformly dispersed with the lamellar structure mineral, the nylon has excellent oil resistance, and the dispersed lamellar structure mineral can resist the penetration of oil; the prepared blended rubber-plastic sheath has excellent oil resistance, and can be used in severe environments such as high-temperature oil immersion and the like for a long time without deformation and cracking; the blended rubber-plastic sheath has the advantages of complete and reliable performance and long service life, and can completely meet the requirements of cable sheaths in specific fields.
Detailed Description
The present invention is further described in the following detailed description with reference to specific embodiments, but it should not be understood that the scope of the present invention is limited to the examples described below.
Example 1
Step , adding 10 parts by weight of layered mineral mica powder into a ball mill, dissolving nylon in dimethylformamide to obtain liquid nylon with the mass concentration of 15%, adding 8 parts by weight of the liquid nylon into a grinding machine for wetting, grinding for 2 hours at the rotating speed of the ball mill of 38r/min, continuously adding 0.5 part by weight of stripping support aid sodium dodecyl sulfate and 0.1 part by weight of silane coupling agent into the ball mill, continuously grinding for 2 hours, and uniformly mixing to obtain a jelly, namely a layered mineral-nylon blend;
and secondly, adding 65 parts by weight of nitrile rubber and 40 parts by weight of chloroprene rubber into an internal mixer for times of internal mixing, wherein the temperature of times of internal mixing is 65 ℃ and the internal mixing time is 4min, then adding 10 parts by weight of auxiliary agent for second internal mixing, wherein the temperature of the second internal mixing is 65 ℃ and the internal mixing time is 10min, then adding 20 parts by weight of layered mineral-nylon blend for third internal mixing, wherein the temperature of the third internal mixing is 65 ℃ and the internal mixing time is 5min, and finally, thinly discharging the mixture through an open mill to obtain the oil-resistant blended rubber-plastic cable sheath material.
Example 2
Step , adding 15 parts by weight of layered mineral talcum powder into a ball mill, dissolving nylon in dimethylformamide to obtain liquid nylon with the mass concentration of 15%, adding 10 parts by weight of liquid nylon into the grinding mill for wetting, grinding for 3 hours at the rotating speed of the ball mill of 38r/min, continuously adding 0.5 part by weight of stripping supporting aid sodium dodecyl benzene sulfonate and 0.1 part by weight of aluminate coupling agent into the ball mill, continuously grinding for 2, and uniformly mixing to obtain a jelly, namely a layered mineral-nylon blend;
and secondly, adding 80 parts by weight of nitrile rubber and 60 parts by weight of chloroprene rubber into an internal mixer for times of internal mixing, wherein the temperature of times of internal mixing is 65 ℃, and the internal mixing time is 4min, then adding 10 parts by weight of auxiliary agent for second internal mixing, wherein the temperature of the second internal mixing is 65 ℃, and the internal mixing time is 10min, then adding 30 parts by weight of layered mineral-nylon blend for third internal mixing, wherein the temperature of the third internal mixing is 65 ℃, and the internal mixing time is 5min, and finally, thinly discharging the mixture through an open mill to obtain the oil-resistant blended rubber-plastic cable sheath material, wherein the auxiliary agent is prepared from the following raw materials, by weight, 2 parts of an anti-aging agent RD, 0.5 part of magnesium stearate, 5 parts of sulfur, 2 parts of a plasticizer DOP, 2 parts of a dispersing agent EBS, 5 parts of a flame retardant and 2 parts of a BDMA promoter, and the flame retardant is composed of 2 parts of red phosphorus, 2 parts of ammonium polyphosphate and 1 part of tric.
Example 3
Step , adding 20 parts by weight of layered mineral montmorillonite mica powder into a ball mill, dissolving nylon in dimethylformamide to obtain liquid nylon with the mass concentration of 15%, adding 15 parts by weight of the liquid nylon into the ball mill for wetting, grinding for 4 hours at the rotating speed of the ball mill of 38r/min, continuously adding 0.5 part by weight of stripping supporting aid sodium dodecyl sulfate and 0.2 part by weight of titanate coupling agent into the ball mill, continuously grinding for 2 hours, and uniformly mixing to obtain a jelly, namely a layered mineral-nylon blend;
and secondly, adding 70 parts by weight of nitrile rubber and 60 parts by weight of chloroprene rubber into an internal mixer for times of internal mixing, wherein the temperature of times of internal mixing is 65 ℃, and the internal mixing time is 4min, then adding 10 parts by weight of auxiliary agent for second internal mixing, wherein the temperature of the second internal mixing is 65 ℃, and the internal mixing time is 10min, then adding 40 parts by weight of layered mineral-nylon blend for third internal mixing, wherein the temperature of the third internal mixing is 65 ℃, and the internal mixing time is 15min, and finally, thinly discharging the mixture through an open mill to obtain the oil-resistant blended rubber-plastic cable sheath material.
Comparative example 1
Comparative example 1 no blending treatment of the layered mineral with nylon but using nylon directly, the rest is as in example 1 . due to the lack of uniform compounding of the layer, the material resists the penetration of oils to be reduced.
Comparative example 2
Comparative example 2 the layered mineral was not blended with nylon but directly used with the layered mineral, the rest being 1 from example 1, since the liquid nylon lacking the liquid nylon carries the layered structure mineral powder, the layered dispersion is poor, making the material less resistant to penetration of oils.
And (3) carrying out performance test on the oil-resistant blended rubber-plastic cable sheath material prepared in the embodiments 1-3 and the oil-resistant blended rubber-plastic cable sheath material prepared in the proportions 1-2.
1. The cable material was pressed into uniform sheets and tested according to the IRHD (international rubber hardness) hardness scale with initial hardness as shown in table 1.
2. And (3) soaking the sheet pressed by the cable material in 105 ℃ engine oil for 24h, testing the change of hardness, and if the hardness is reduced, indicating that the engine oil dissolves the cable material, so that the cable material swells, and judging that the oil resistance is poor. As shown in table 1.
TABLE 1
Test items
|
Example 1
|
Example 2
|
Example 3
|
Comparative example 1
|
Comparative example 2
|
Hardness (IRHD)
|
76
|
77
|
78
|
77
|
77
|
Hardness Change (24 h, 105 ℃ oil)
|
-5
|
-4
|
-6
|
-17
|
-15 |
As can be seen from the data in table 1, the addition of the layered mineral-nylon blend has the advantage of good resistance to high temperature oil immersion.