Composite rubber-polymer wear-resistant material for hydraulic devices

FIELD: chemistry.

SUBSTANCE: invention can be used in machine-building to make wear-resistant rod packing and cylinders of hydraulic devices instead of rubber fabric chevron seals, as well as for articles for construction purposes in mining, oil and gas extraction and chemical industry. The rubber mixture based on cis-isoprene rubber SKI-3 - 100 pts.wt contains the following, pts.wt: ultra-high molecular weight polyethylene, modified 7 wt % carbonaceous material carbosil - 170, viscose fibre filler, saturated with latex-resorcinol-formaldehyde composition - banavis - 80, active technical carbon P-234 - 30, petroleum oil - softening agent - netoxol 5, zinc oxide - 5, stearic acid - 1, sulphur - 3, sulfonamide C 1.6, diaphene antiageing agent FP-1, antiozonant-acetonanil N - 1.

EFFECT: articles obtained from the rubber-polymer material have extremely high rigidity, frame structure, resistance to frictional forces, weak acid and alkaline solutions, while partially retaining elasticity, high hardness under intense wear conditions.

1 tbl

 

The invention relates to polymeric materials and can be used in machinery for the manufacture of wear resistant seals rod and hydraulic cylinder units instead of herringbone rubber cuffs, as well as for products for structural purposes in the mining, oil and gas and chemical industry for the manufacture of bearings, gears, wheels, skid plates, levers, operating in a wide temperature interval under heavy wear in the environment, air, mineral oils, water emulsions, mild acids and alkalis.

Most modern structural materials based on polymer matrices have complex requirements for resistance to the action of oils, physico-mechanical, cold-resistant, wear-resistant, thermal and other characteristics. In this regard, when creating composites it is necessary to select the components that have complex effect on the polymer matrix, providing a synergistic effect. These components include ultra-high molecular weight polyethylene.

Known self-lubricating thermoplastic polymer composition with improved wear resistance comprising a mixture in the form of a melt of thermoplastic polymer polyolefins of ultrahigh molecular what about the weight (RF Patent 97115931 C08L 23/02). Material intended for the manufacture of molded parts - bearings, gears, wheels, skid plates, levers. However, this material has insufficient rigidity and frame that does not allow you to use it in engineering responsible for making structural products.

Known antifriction polymeric composition containing polyformaldehyde, modified barium sulfate, talc and boron nitride, and ultra-high molecular weight polyethylene (UHMWPE) (USSR Author's certificate 1670911 C08L 59/02). The material has high physical and mechanical properties and effective when used as a structural material for mechanical engineering, in particular machine tools in the manufacture of parts copiers finishing-turning machines. However, the material is characterized by a low frost resistance and the rate of abrasion.

Known composite material based on recycled polymeric material or rubber and skeletal body for hexagonal panels for pavement areas, roads, footpaths (RF Patent 2310032). The material can carry substantial loads in the temperature range from minus 30°C to plus 60°C. the Disadvantage of the material is low frost resistance and abrasion resistance, which are determining the La products of similar type.

Known wear-resistant, cyclododecanone, oil and petrol resistant composite material based on polyurethane, of which the company LLC "Uralpromkomplekt" produced a wide range of products for the mining, oil and gas and chemical industries, including polyurethane cuff herringbone according to GOST 22704. The material has a sufficiently high resistance to oils, grease, oil, fuel, has a high uprugoopticheskii properties and high hardness. However, composite material based on polyurethane has a tendency to hydrolysis, destruction under the action of water vapor and hot water, excessive heat buildup during repeated deformation, low temperature resistance and very high cost.

Based on the results of the patent search, the proposed material does not have a prototype, because it is not described composite material on the basis of UHMWPE, which includes the ingredients, typical of the rubber composition (rubber, vulcanizing the group, antioxidants and so on), using as filler viscose fabric fibers.

The objective of the invention is to develop a cheap durable construction rezinopolimernykh material with physical-mechanical characteristics meet the requirements of the materials used is adequate for the manufacture of parts for the mining, oil, gas and chemical industry, namely, rod seals and hydraulic cylinder devices, instead of the herringbone rubber seals for bearings, gears, wheels, skid plates, levers, operating in an environment of air, water, mild acids and alkalis in heavy wear at the temperature from minus 50 to plus 80°C.

To solve this problem developed rezinopolimernykh composite material based on modificirovannogo UHMWPE and available and inexpensive synthetic CIS-isoprene rubber SKI-3 domestic production with the introduction of viscose fiber filler - banavie. This increases the hardness, stiffness and frame obtained products while maintaining some flexibility. At the same time on the surface of articles formed of the wear-resistant layer is able to withstand intense wear in the environment, air, mineral oils, water, water emulsions, mild acids and alkalis.

Technical result achieved in the implementation of the invention is to obtain rezinopolimernykh composite material having high tribological characteristics, resistant to water, mild acids and alkalis, mineral oils, water emulsions, can also for init coated rubber blend fabric in the manufacture of herringbone cuff; this significantly reduces labor costs.

The problem is solved in that the composite material contains a modified ultra-high molecular weight polyethylene, CIS-isoprene rubber SKI-3, viscose fiber filler Banovic, active carbon P-234, oil softening agent for rubber industry - naloxol, inorganic vulcanization accelerator is zinc oxide (zinc white), organic vulcanization activator - stearic acid, the main curing substance is sulfur, the vulcanization accelerator (N-cyclohexyl-2-benzothiazolylsulfenamide (Sulfenamid C), antioxidants - N-phenyl-N'-isopropylpyrimidine (deafen AF) and polymerized 2,2,4'-trimethyl-1,2-dihydroquinoline (acetonyl N).

Used the modified ultra-high molecular weight polyethylene (UHMWPE), which belongs to the class of polyethylenes of low pressure (PAPD); due to its unique structure, giant molecular weight of UHMWPE has a higher physical and mechanical characteristics, resistance to aggressive environments, improved tribological and frost-resistant properties than the rest of the polyethylene class PAPD. UHMWPE modified nano-modifier - carbon material - carbosil of 7%. It is a natural material, we settled on a carbon substance in recrystallizes condition, contains a large number of metamorphosed organic matter. He has a high chemical resistance, high enough, high abrasion resistance and frost resistance. As the elastic component used CIS-isoprene rubber SKI-3, representing stereoregular CIS-1,4-polyisoprene containing parts of CIS-1,4 not less than 96%.

As fillers of composite material used active carbon P-234 and viscose fiber filler Banovic, which is a viscose rayon untwisted thread length 4±2 mm, impregnated with latex-resorcinol-formaldehyde composition (TU 6-06-11-129-87) Because Banovic is a tissue filler, it gives the finished product a special rigidity and frame.

The plasticizer is highly refined deparaffinization oil oil softening agent for rubber industry - naloxol (TU 38.101999-84).

Curing group for SKI-3 contains inorganic vulcanization accelerator is zinc oxide (zinc white), organic vulcanization activator - stearic acid, the main curing substance is sulfur, the vulcanization accelerator (N-cyclohexyl-2-benzothiazolylsulfenamide (Sulfenamid C), the antioxidant is N-phenyl-N'-isopropylpyrimidine ((deafen AF) and antiozonant - floor is narisovannyi 2,2,4 '-trimethyl-1,2-dihydroquinoline (acetonyl N).

The composition rezinopolimernykh composite material according to the invention, following, in parts by weight/% by weight:

- ultra-high molecular weight polyethylene, modified mixer percussion 7 wt.% carbonaceous material carbosil fraction size not more than 50 μm - 170,0/42,76;

- CIS-isoprene rubber SKI-3 -100,0 / to 25.15;

- of viscose rayon untwisted thread length 4±2 mm, impregnated with latex-resorcinol-formaldehyde composition (Banovic) - 80,0 /20,12;

- active carbon black P-234 -30,0 / 7,55;

- highly refined deparaffinization oil oil softening agent for rubber industry - naloxol - 5,0 /1,26;

- inorganic vulcanization accelerator is zinc oxide (zinc white) - 5,0 / 1,26;

- organic vulcanization activator - stearic acid - 1,0/0,25;

- the main curing substance - sulfur - 3,0 / 0,75;

the vulcanization accelerator M-cyclohexyl-2-benzothiazolyl sulfenamid (Sulfenamid C) -1,6 / 0,40;

- antioxidant - N-phenyl-N'-isopropylpyrimidine (deafen AF) - 1,0 /0,25;

antiozonant - polymerized 2,2,4'-trimethyl-1,2-dihydroquinoline (acetonyl N)-1,0 / 0,25.

An example of obtaining the claimed composite material

Modification of UHMWPE produced in the mixer percussion. This way modificat and provides the most uniform distribution of the modifier in UHMWPE. A portion of the natural carbon-containing material - carbosil fraction size not more than 50 μm in an amount of 7% by weight UHMWPE together with UHMWPE was placed in the drum of the mixer drum type and stirred at a speed of rotation of the drums 450 rpm for 5-7 minutes

Mixing rezinopolimernykh material produced in two stages:

1st stage mixing. Prepared sample of rubber and ingredients of the composite material by weight according to the recipe. Mixing the composite material produced in the mill PD 320160/160 at the initial temperature of the surface of the rolls 30±5°C. the Sequence of input ingredients: valavala rubber SKI-3 when the gap between the rollers 1±0.5 mm, then typed stearic acid, sulfenamid C, zinc white, deafen OP, acetonyl N; regulate the magnitude of the gap rolls so that the rolls were well-handled stock mixture, introduced a modified UHMWPE, have introduced carbon black P-234 together with metaxalon, stirred for at least 15 minutes, bringing the temperature of the rolls rolls up to 80-90°C. was Removed the mixture with rolls were cooled in water to cool and put on the shelves for "curing" not less than 24 hours.

2nd stage mixing. Downloaded a mixture of 1-St stage on drums PD 320 160/160 at the initial temperature of the surface of the rolls 30±5°C. and was injected sulfur. Regulation is Ali gap rolls to a minimum and introduced Banovic with constant cooling of the rolls, the temperature of the rolls should not exceed 55°C. the Total time of mixing 45-55 minutes cure of the laboratory samples was conducted on the vulcanizing press 800×800 at a temperature of 165°C for 10 min) at a specific pressure of not less than 70 MPa.

Features durable rezinopolimernykh composite material are shown in table 1.

As can be seen from table 1, the material has a very low unique to rezinopolimernykh compositions abrasion, and the products are extremely rigid, frame and retain some elasticity. The effect of stiffness and Carcassone is achieved by a modified UHMWPE in the number 42,76% and banavie in the number 20,12%, and the effect of elasticity is due to CIS-isoprene rubber SKI-3 with an appropriate curing and protecting group. The increase in the content of the modified UHMWPE and banavie stated above reduces the total effect, and the reduction does not provide additional affectionatly stated rezinopolimernykh composite material is increased frame stiffness derived products, their high tribological properties due to the use of the modified UHMWPE and tissue filler.

The use of this invention will significantly improve the endurance of the sealing device is STV hydraulic seals due to high wear resistance, stiffness and carcanet composite material.

Developed material can be used for the manufacture of bearings, gears, wheels, skid plates, levers, operating in a wide temperature interval under heavy wear in the environment, air, mineral oils, water emulsions, mild acids and alkalis, as well as for rod seals and hydraulic cylinder units instead of herringbone rubber cuffs.

Table 1
Description casinoballroom composite material
Indices
Conditional tensile strength, MPa10.3
Elongation at break, %66
Residual elongation, %18
Relative residual deformation of compression in the air, 30% at 70°C for 22 h, %40
Abrasion, cm3/kWhAt 32.28
The coefficient of starane the relative elongation, at 70°C for 144 h in air, %-6,13
Hardness, usled89
Density, g/cm31,00

Composite rezinopolimernykh durable material for sealing hydraulic devices, characterized in that it is made on the basis of ultra-high molecular weight polyethylene, modified 7 wt.% carbonaceous material carbosil, fraction size not exceeding 50 microns in mixer percussion and contains CIS-isoprene rubber SKI-3, viscose fiber filler - of viscose rayon untwisted thread a length of 2-6 mm, impregnated with latex-resorcinol-formaldehyde composition - banawi, active carbon P-234, highly refined deparaffinization oil oil softening agent for rubber industry - naloxol, inorganic vulcanization accelerator is zinc oxide (zinc white),organic vulcanization activator-stearic acid, the main curing substance is sulfur, vulcanization accelerator cyclohexyl-2-benzothiazolylsulfenamide-sulfenamid C, antioxidant - N-phenyl-N'-isopropyl-paraphenylenediamine - deafen OP, antiozonant - polymerized 2,2,4'-trimethyl-1,2-dihydroquinoline - acetonyl N with the following ratio of components, parts by weight/% by weight:

ultra-high molecular weight polyethylene, modified 7 wt.%
carbonaceous material carbosil, fraction size
50 μm in the mixer percussion170/42,6
CIS-isoprene rubber SKI-3100/25,15
viscose fiber filler -
viscose rayon untwisted thread a length of 2-6 mm
impregnated latex-resorcinol-formaldehyde composition - banawi80/20,12
active carbon P-23430/7,55
highly refined deparaffinization oil
oil-softening agent for rubber industry - naloxol5/1,26
inorganic vulcanization accelerator is zinc oxide (zinc white)5/1,26
the main curing substance is sulfur3/0,75
the accelerator of vulcanization -
cyclohexyl-2-benzothiazolylsulfenamide-sulfenamid C1,6/0,4
antioxidant - N-phenyl-N'-isopropyl-paraphenylenediamine - deafen AF1/0,25
antiozonant - polymerized 2,2,4'-trimethyl-1,2-dihydroquinoline - acetonyl N1/0,25



 

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