CN111849083A

CN111849083A - Production method of damping, sound-absorbing and noise-reducing sealing rubber for chemical pump

Info

Publication number: CN111849083A
Application number: CN202010559713.7A
Authority: CN
Inventors: 徐向远
Original assignee: Anhui Tenglong Pump And Valve Manufacturing Co ltd
Current assignee: Anhui Tenglong Pump And Valve Manufacturing Co ltd
Priority date: 2020-06-18
Filing date: 2020-06-18
Publication date: 2020-10-30
Anticipated expiration: 2040-06-18
Also published as: CN111849083B

Abstract

The invention belongs to the field of high polymer materials, and particularly relates to a production method of a chemical pump damping sound absorption and noise reduction sealing rubber, which is simple in production method and wide in raw material source, improves corrosion resistance by using sulfonated graphite oxide, unexpectedly obtains a high loss effect, greatly improves effective loss of the sealing rubber, is wide in raw material source, is simple and easy to implement in production method, can be used in a chemical pump for many years without great change in acoustic performance, can meet the sound absorption and noise reduction requirements of the chemical pump, and has good corrosion resistance.

Description

Production method of damping, sound-absorbing and noise-reducing sealing rubber for chemical pump

Technical Field

The invention belongs to the technical field of high polymer materials, and particularly relates to a production method of damping, sound-absorbing and noise-reducing sealing rubber for a chemical pump.

Background

The chemical pump is widely used for water supply and drainage in industry and city, and also can be used for irrigation and drainage in farmland and orchard for delivering clear water or other liquids. With the progress of chemical pump technology, the industrialization level is continuously improved, people continuously enhance the environmental awareness, the noise reduction problem of the gear pump is generally regarded as important for the chemical pump due to the special working environment of the chemical pump, for example, in the aspect of energy saving and noise reduction in polymer-biochemical workshops of Daqing refining company, the mechanical pump is modified to reduce noise pollution and save a large amount of funds, but no leakage is always pursued by chemical equipment, but no leakage and a long path is required to be taken, such as the problem of material cavitation, the problem of reliability of static sealing and the like. However, the aging resistance of rubber is poor, for example, CN109504007A A rubber sealing material for chemical pumps discloses that the rubber sealing material for chemical pumps prepared by the invention has good mechanical property, corrosion resistance, wear resistance and impact resistance. However, polytetrafluoroethylene is used as a main raw material and is not pure rubber, a vulcanizing agent used in the method cannot vulcanize the polytetrafluoroethylene, the polytetrafluoroethylene is sintered and molded and cannot be mixed with other materials for processing, and a prepared sealing material cannot obtain a good use effect; the sound energy is gradually attenuated, so that the purpose of sound absorption is achieved, and sound absorption and noise reduction are realized by utilizing the characteristic of multiple holes. However, the use of porous sound absorption and noise reduction is common knowledge in life, and the porous sound absorption and noise reduction can not ensure sealing, and is greatly limited and restricted in the sealing application of chemical pumps, no products and corresponding technologies related to the chemical pump damping sound absorption and underwater noise reduction rubber with better performance exist in the current market, the existing rubber sealing material is difficult to balance in the aspects of pressure resistance, vibration reduction, weather resistance, corrosion resistance and the like without the chemical pump liquid environment, the preparation method is complex, the cost is high, the material use is limited, the current materials are mostly polytetrafluoroethylene plastics and the like, the sound absorption and noise reduction in the liquid environment of the current corrosion-resistant chemical pump can not be widely met, the sound absorption and noise reduction materials also have good comprehensive performances of vibration reduction, corrosion resistance and the like, the materials such as the existing underwater sound absorption polyurethane and the like can not meet the requirements of the corrosion-resistant use environment of the chemical pump, and technical, on the basis of urgent need for developing sealing rubber with balanced performance for chemical pumps, a production method of damping sound absorption and noise reduction sealing rubber for chemical pumps is urgently needed to be developed to meet the existing technical requirements and performance requirements.

Disclosure of Invention

Aiming at the problems, the invention aims to provide a production method of the damping, sound-absorbing and noise-reducing sealing rubber for the chemical pump.

The invention is realized by the following technical scheme:

a production method of a chemical pump damping sound absorption noise reduction sealing rubber comprises the following steps:

firstly, preparing chlorosulfonated butyl rubber: dissolving crushed butyl rubber in carbon tetrachloride at 65-75 ℃ to form 100-150 g/L solution, adding 0.2-0.4 part of ethanolamine and 0.1-0.2 part of azodiisobutyronitrile initiator into the solution, blowing a chlorine sulfonating agent with a volume ratio of chlorine to sulfur dioxide of 1: 2 into the solution at 70 ℃, wherein the chlorine content is 0.8-1.0%, and when the sulfonation degree is 0.170-0.190 meq/g, removing acid gas, adding diisopropylamine to neutralize to a pH value of 7.2-7.4, adding water into the quenched solution, emulsifying the mixture of water and the quenched solution to form slurry for neutralizing sulfonated polymers, removing the solvent from the slurry, separating powder particles from the water, and drying to constant weight to obtain powder particles;

secondly, adjusting the temperature of an open mill to 80-85 ℃, adjusting the roll spacing to 0.6-0.65 mm, adding 100-105 parts of chlorosulfonated butyl rubber obtained in the step (1), coating a front roll with the rubber, uniformly adding a mixture of 1-2 parts of stearic acid and 5-8 parts of sericite powder along a roller of the open mill at a constant speed, adding all scattered materials into a rubber material during mixing, performing 3/4 operations from each side once, adding 1-2 parts of zinc oxide, adding all scattered zinc oxide into the mixed rubber material, performing 3/4 cutting operations from each side alternately twice, discharging sheets, adjusting the roll spacing to 0.7-0.8 mm, rolling the mixed rubber longitudinally and passing through for five times, and discharging the rubber to obtain the mixed rubber;

And thirdly, putting the rubber compound obtained in the second step, poly-1-butene, ionic liquid, sulfonated graphite oxide and chlorinated polypropylene into an internal mixer according to a certain proportion, blending at 160-170 ℃, rotating at 10-20 r/min until torque and temperature are stable, and extruding to obtain the modified ethylene-propylene rubber.

Further, the preparation method of the sulfonated graphite oxide comprises the following steps: weighing 4-4.5 parts by weight of expanded graphite, 2.5-3 parts by weight of potassium nitrate and 55-64 parts by weight of concentrated sulfuric acid, uniformly mixing in a reaction vessel in an ice water bath, mechanically stirring for 20-30 min, slowly adding 8.7-9.5 parts by weight of potassium permanganate, and mechanically stirring at low temperature for 30-60 min; heating to 35-40 ℃ in water bath, reacting for 1-1.5 h at constant temperature, adding 54-65 parts of deionized water, reacting for 2-4 h at constant temperature in water bath at 90-95 ℃, cooling to 55-60 ℃, adding 35-40 parts of 30% hydrogen peroxide by mass, stirring uniformly by magnetic force, washing with dilute hydrochloric acid and deionized water to neutrality, filtering, adding 10-15 parts of aminobenzene sulfonic acid, stirring for 6h at 25-30 ℃, performing centrifugal separation on the product, washing with water to neutrality, and freeze-drying to obtain the sulfonated graphite oxide.

Further, the butyl rubber of the step (1) is a copolymer of isobutylene and isoprene, and the amount of the isoprene monomer unit is 0.5-3.0% of the total amount of all monomer units of the butyl rubber; the weight average molecular weight of the butyl rubber is 30-50 ten thousand.

Further, the N-ethylpyridine bromide salt, the N-hexylpyridine hexafluorophosphate salt or the N-butylpyridine bis (trifluoromethanesulfonyl) imide salt.

Further, the chlorinated polypropylene has a chlorine content of 25-30%.

Further, the poly-1-butene is poly-1-butene resin with the melt index of 0.4-0.6 g/10 min.

Further, the mixing ratio of the rubber compound in the step (3), the poly-1-butene, the ionic liquid, the sulfonated graphite oxide and the chlorinated polypropylene is 50: 60-65: 25-30: 12-15 in parts by weight.

The invention has the beneficial effects that:

the rubber sealing material prepared by the production method does not need an additional vulcanizing agent and a vulcanizing method, has good thermoplastic processing performance, and after the rubber compound is plasticized by the ionic liquid, the groups in the ionic liquid obstruct the interaction of sulfonate groups, reduce intermolecular force and have internal plasticizing effect. The sulfonated graphite oxide is added into the rubber matrix, so that filler particles are uniformly distributed around the polymer network, when sound waves act on the material, the polymer network generates local expansion and compression, and simultaneously, the filler particles vibrate along with the polymer network, so that the relaxation and absorption effects of the material on sound energy are increased, the internal loss of the material can be improved, the flaky graphite fluoride is added into the rubber matrix, and the internal layering of the flaky sulfonated graphite oxide can form gaps which can generate relative friction and cavity resonance effect under the action of external sound waves to jointly lose the sound energy. In addition, the scattering and refraction effects of the sericite powder filler increase the propagation path of sound waves in the material, which is beneficial to attenuation of sound energy, meanwhile, the heterogeneity of local structure can also convert partial compression deformation generated under the action of the sound waves into shear deformation, which is beneficial to increase the loss absorption of viscoelastic materials to the sound energy, and the introduction of sulfonated graphite oxide indirectly improves the acid-base corrosion resistance and wear resistance of the sealing rubber, has excellent waterproof and oil-proof functions, has good hydrophobicity, the blending of the poly-1-butylene and the graphite fluoride improves the strength, and the characteristic impedance of chlorosulfonated butyl rubber is more matched with that of an aqueous medium, so that the sound waves can enter a sound absorption system without reflection; through the blending of the rubber component, the sulfonated graphite oxide and the sericite powder have large attenuation, so that most of incident sound energy is absorbed.

Compared with the prior art, the invention has the following advantages:

the chemical pump sealing rubber prepared by the production method disclosed by the invention has the advantages of high internal consumption, good water resistance and corrosion resistance, good thermal plasticity processing and excellent aging resistance, the corrosion resistance is improved by using the sulfonated graphite oxide, the high loss effect is obtained unexpectedly, the effective loss of the sealing rubber is greatly improved, the source of the adopted raw materials is wide, the production method is simple and easy, the acoustic performance of the sealing rubber in the chemical pump can be unchanged after years of use, the requirements of sound absorption and noise reduction of the chemical pump can be met, and the sealing rubber has good corrosion resistance.

Detailed Description

The invention is illustrated by the following specific examples, which are not intended to be limiting.

Example 1

(1) preparation of chlorosulfonated butyl rubber: dissolving crushed butyl rubber in carbon tetrachloride at 75 ℃ to form 100 parts of 150g/L solution, adding 0.4 part of ethanolamine and 0.2 part of azodiisobutyronitrile initiator into the solution, blowing a chlorine sulfonating agent with the volume ratio of chlorine to sulfur dioxide of 1: 2 into the solution at 70 ℃, removing acid gas when the chlorine content is 1.0 percent and the sulfonation degree is 0.190meq/g, adding diisopropylamine into the solution to neutralize the pH value to 7.4, adding water into the quenched solution, emulsifying the mixture of the water and the quenched solution to form slurry of neutralized sulfonated polymer, removing the solvent from the slurry, separating powder particles from the water, and drying the powder particles to constant weight to obtain the powder particles; (2) adjusting the temperature of an open mill to 85 ℃, adjusting the roll spacing to 0.65mm, adding 105 parts of chlorosulfonated butyl rubber obtained in the step (1), coating the rubber on a front roll, uniformly adding a mixture of 2 parts of stearic acid and 8 parts of sericite powder along the roller of the open mill at a constant speed, adding all scattered materials into a rubber material during mixing, making 3/4 cutters from each side once, adding 1-2 parts of zinc oxide, adding all scattered zinc oxide into the mixed rubber material, alternately making 3/4 cutters from each side twice, discharging sheets, adjusting the roll spacing to 0.8mm, rolling the mixed rubber longitudinally and thinly passing through for five times, and discharging the rubber to obtain the mixed rubber; (3) and (3) putting the rubber compound obtained in the step (2), poly-1-butene, ionic liquid, sulfonated graphite oxide and chlorinated polypropylene into an internal mixer according to a certain proportion, blending at 170 ℃, rotating at the speed of 20r/min until torque and temperature are stable, and extruding to obtain the sulfonated graphite oxide, wherein the preparation method of the sulfonated graphite oxide comprises the following steps: weighing 4.5 parts of expanded graphite, 3 parts of potassium nitrate and 64 parts of concentrated sulfuric acid in parts by weight, uniformly mixing in a reaction vessel in an ice-water bath, mechanically stirring for 30min, slowly adding 9.5 parts of potassium permanganate, and mechanically stirring at low temperature for 60 min; heating to 40 ℃ in water bath for reacting at constant temperature for 1.5h, adding 65 parts of deionized water, reacting at constant temperature in 90 ℃ in water bath for 4h, cooling to 60 ℃, adding 35 parts of 30 mass percent hydrogen peroxide, uniformly stirring by magnetic force, washing with dilute hydrochloric acid and deionized water to be neutral, filtering, adding 15 parts of aminobenzenesulfonic acid, stirring at 30 ℃ for 6h, centrifugally separating a product, washing with water to be neutral, and freeze-drying to obtain a sulfonated graphite oxide, wherein the butyl rubber in the step (1) is a copolymer of isobutylene and isoprene, and the amount of isoprene monomer units is 3.0% of the total amount of all monomer units of the butyl rubber; the weight average molecular weight of the butyl rubber is 50 ten thousand, one of N-ethylpyridine bromide salt, N-hexylpyridine hexafluorophosphate or N-butylpyridine bis (trifluoromethanesulfonyl) imide salt is selected, the chlorinated polypropylene with the chlorine content of 25-30% is selected, the poly-1-butene is poly-1-butene resin with the melt index of 0.4g/10min, the mixing ratio of the rubber compound in the step (3) to the poly-1-butene, the ionic liquid, the sulfonated graphite oxide and the chlorinated polypropylene in parts by weight is 50: 65: 30: 15, and the poly-1-butene resin is purchased from Mitsui chemical M4142.

Example 2

(1) Preparation of chlorosulfonated butyl rubber: dissolving crushed butyl rubber in carbon tetrachloride at 65 ℃ to form 100g/L solution, adding 0.2 part of ethanolamine and 0.1 part of azodiisobutyronitrile initiator into the solution, blowing a chlorine sulfonating agent with the volume ratio of chlorine to sulfur dioxide of 1: 2 into the solution at 70 ℃, removing acid gas when the chlorine content is 1.0 percent and the sulfonation degree is 0.170meq/g, adding diisopropylamine into the solution to neutralize the pH value to 7.2, adding water into the quenched solution, emulsifying the mixture of the water and the quenched solution to form slurry for neutralizing sulfonated polymer, removing the solvent from the slurry, separating powder particles from the water, and drying the powder particles to constant weight to obtain the powder particles; (2) adjusting the temperature of an open mill to 80-85 ℃, adjusting the roll spacing to 0.6-0.65 mm, adding 100-105 parts of chlorosulfonated butyl rubber obtained in the step (1), coating a front roll with the rubber, uniformly adding a mixture of 1 part of stearic acid and 5 parts of sericite powder along a roller of the open mill at a constant speed, adding all materials scattered in the mixing period into a rubber material, performing 3/4 cutters from each side once, adding 1 part of zinc oxide, adding all scattered zinc oxide into the mixed rubber material, performing 3/4 cutters from each side alternately for two times, discharging sheets, adjusting the roll spacing to 0.7mm, rolling the mixed rubber longitudinally and thinly passing through for five times, and discharging the rubber to obtain the mixed rubber; (3) and (3) putting the rubber compound obtained in the step (2), poly-1-butene, ionic liquid, sulfonated graphite oxide and chlorinated polypropylene into an internal mixer according to a certain proportion, blending at 160 ℃, rotating at 10r/min until torque and temperature are stable, and extruding to obtain the sulfonated graphite oxide, wherein the preparation method of the sulfonated graphite oxide comprises the following steps: weighing 4 parts by weight of expanded graphite, 2.5 parts by weight of potassium nitrate and 55 parts by weight of concentrated sulfuric acid, uniformly mixing in a reaction vessel in an ice water bath, mechanically stirring for 20min, slowly adding 8.7 parts by weight of potassium permanganate, and mechanically stirring at low temperature for 30 min; heating to 35 ℃ in a water bath, reacting at a constant temperature for 1h, adding 54 parts of deionized water, reacting at a constant temperature in a 90 ℃ water bath for 2h, cooling to 55 ℃, adding 3 parts of 30 mass percent hydrogen peroxide, uniformly stirring by magnetic force, washing with diluted hydrochloric acid and deionized water to be neutral, filtering, adding 10 parts of aminobenzenesulfonic acid, stirring at 25 ℃ for 6h, centrifugally separating a product, washing with water to be neutral, and freeze-drying to obtain a sulfonated graphite oxide, wherein the butyl rubber in the step (1) is a copolymer of isobutylene and isoprene, and the amount of isoprene monomer units is 3.0% of the total amount of all monomer units of the butyl rubber; the weight average molecular weight of the butyl rubber is 50 ten thousand, one of N-ethylpyridine bromide salt, N-hexylpyridine hexafluorophosphate or N-butylpyridine bis (trifluoromethanesulfonyl) imide salt is selected, the chlorinated polypropylene with the chlorine content of 30 percent, the poly-1-butene is poly-1-butene resin with the melt index of 0.6g/10min, the mixture in the step (3) is mixed with the poly-1-butene, the ionic liquid, the sulfonated graphite oxide and the chlorinated polypropylene according to the weight parts of 50: 65: 30: 15, and the poly-1-butene resin is purchased from Basell 4235.

Comparative example 1

This comparative example 1 compares to example 1 in that no chlorosulfonating agent is used in step (1), except that the process steps are otherwise identical.

Comparative example 2

This comparative example 2 compares to example 2 in step (3) no sulfonated graphite oxide is used, except that the process steps are otherwise the same.

Comparative example 3

This comparative example 3 compares to example 2, in which step (3) uses no chlorinated polypropylene, except that the process steps are otherwise the same.

Comparative example 4

This comparative example 4 compares to example 2, in step (3) no poly-1-butene is used, except that the process steps are otherwise the same.

Comparative example 5

In this comparative example 4, compared with example 2, no ionic liquid was used in step (3) except that the process steps were otherwise identical.

The performance test results of the damping, sound-absorbing and noise-reducing sealing rubber for the chemical pumps in the embodiments 1 to 2 and the comparative examples 1 to 5 are shown in table 1:

table 1 comparison result of physical and chemical performance test of damping, sound absorption and noise reduction sealing rubber for chemical pump in embodiment and comparative examples 1-5

Note: reference is made to a GB/T531-2008 vulcanized rubber or thermoplastic rubber press-in hardness test method; GB/T3512-2001 vulcanized rubber or thermoplastic rubber hot air accelerated aging and heat resistance tests; GB/T8170-2008 numerical value reduction rule and the representation and judgment of limit numerical value; GB/T11211-2009 vulcanized rubber or thermoplastic rubber and metal adhesive strength determination two-plate method; GB/T13295-2008 nodular cast iron pipes, pipe fittings and accessories for water and gas pipelines; GB/T15254-1994 vulcanized rubber and metal bonding 180 DEG peeling test; HG/T3090-1987 general provisions for the quality of the appearance of molded and extruded rubber articles; GB/T1690-2010 vulcanized rubber or thermoplastic rubber liquid resistance test method; GB/T7762-2014 vulcanized rubber or thermoplastic rubber resists the ozone crack static tensile test; a 57mm pulse sound tube, a water temperature of 22 ℃, a frequency of 3kHzGB/T5266-2006 longitudinal wave sound velocity and attenuation measurement pulse tube method of the underwater acoustic material; measuring sound absorption coefficient and sound impedance in the GBT18696.1-2004 acoustic impedance tube; .

In summary, the chemical pump damping sound absorption noise reduction sealing rubber prepared by the method has good aging resistance and heat resistance improvement effects, excellent mechanical properties, slightly reduced hardness, good underwater sound absorption modification effect, good heat resistance, suitability for use in high-temperature environments and good application value, and is matched with impedance of conveyed liquid.

Claims

1. A production method of a chemical pump damping sound absorption noise reduction sealing rubber is characterized by comprising the following steps:

(1) preparation of chlorosulfonated butyl rubber: dissolving crushed butyl rubber in carbon tetrachloride at 65-75 ℃ to form 100-150 g/L solution, adding 0.2-0.4 part of ethanolamine and 0.1-0.2 part of azodiisobutyronitrile initiator into the solution, blowing a chlorine sulfonating agent with a volume ratio of chlorine to sulfur dioxide of 1: 2 into the solution at 70 ℃, wherein the chlorine content is 0.8-1.0%, and when the sulfonation degree is 0.170-0.190 meq/g, removing acid gas, adding diisopropylamine to neutralize to a pH value of 7.2-7.4, adding water into the quenched solution, emulsifying the mixture of water and the quenched solution to form slurry for neutralizing sulfonated polymers, removing the solvent from the slurry, separating powder particles from the water, and drying to constant weight to obtain powder particles;

(2) Adjusting the temperature of an open mill to 80-85 ℃, adjusting the roll distance to 0.6-0.65 mm, adding 100-105 parts of chlorosulfonated butyl rubber obtained in the step (1), coating a front roll with the rubber, uniformly adding a mixture of 1-2 parts of stearic acid and 5-8 parts of sericite powder along a roller of the open mill at a constant speed, adding all materials scattered in the mixing period into a rubber material, performing 3/4 cutting knife once from each side, adding 1-2 parts of zinc oxide, adding all scattered zinc oxide into the mixed rubber material, alternately performing 3/4 cutting knives twice from each side, discharging sheets, adjusting the roll distance to 0.7-0.8 mm, rolling the mixed rubber for five times longitudinally and discharging the rubber to obtain the mixed rubber;

(3) and (3) putting the rubber compound obtained in the step (2), poly-1-butene, ionic liquid, sulfonated graphite oxide and chlorinated polypropylene into an internal mixer according to a certain proportion, mixing at 160-170 ℃, rotating at 10-20 r/min until torque and temperature are stable, and extruding to obtain the modified polycarbonate.

2. The production method of the chemical pump damping, sound absorption and noise reduction sealing rubber as claimed in claim 1, wherein the preparation method of the sulfonated graphite oxide comprises the following steps: weighing 4-4.5 parts by weight of expanded graphite, 2.5-3 parts by weight of potassium nitrate and 55-64 parts by weight of concentrated sulfuric acid, uniformly mixing in a reaction vessel in an ice water bath, mechanically stirring for 20-30 min, slowly adding 8.7-9.5 parts by weight of potassium permanganate, and mechanically stirring at low temperature for 30-60 min; heating to 35-40 ℃ in water bath, reacting for 1-1.5 h at constant temperature, adding 54-65 parts of deionized water, reacting for 2-4 h at constant temperature in water bath at 90-95 ℃, cooling to 55-60 ℃, adding 35-40 parts of 30% hydrogen peroxide by mass, stirring uniformly by magnetic force, washing to neutrality by using dilute hydrochloric acid and deionized water, filtering, adding 10-15 parts of aminobenzene sulfonic acid, stirring for 6h at 25-30 ℃, performing centrifugal separation on the product, washing to neutrality by using water, freezing

Drying to obtain the sulfonated graphite oxide.

3. The production method of the damping, sound-absorbing and noise-reducing sealing rubber for the chemical pump as claimed in claim 1, wherein the butyl rubber in the step (1) is a copolymer of isobutylene and isoprene, and the amount of the isoprene monomer unit is 0.5-3.0% of the total amount of all monomer units of the butyl rubber; the weight average molecular weight of the butyl rubber is 30-50 ten thousand.

4. The production method of the chemical pump damping, sound absorption and noise reduction sealing rubber as claimed in claim 1, wherein one of N-ethylpyridine bromide salt, N-hexylpyridine hexafluorophosphate salt or N-butylpyridine bis (trifluoromethanesulfonyl) imide salt is used.

5. The production method of the damping, sound-absorbing and noise-reducing sealing rubber for the chemical pump as claimed in claim 1, wherein the chlorinated polypropylene has a chlorine content of 25-30%.

6. The production method of the damping, sound-absorbing and noise-reducing sealing rubber for the chemical pump as claimed in claim 1, wherein the poly-1-butene is a poly-1-butene resin with a melt index of 0.4-0.6 g/10 min.

7. The production method of the damping, sound-absorbing and noise-reducing sealing rubber for the chemical pump as claimed in claim 1, wherein the mixing ratio of the rubber compound in the step (1) to the poly-1-butene, the ionic liquid, the sulfonated graphite oxide and the chlorinated polypropylene is 50: 60-65: 25-30: 12-15 in parts by weight.