CN100532440C - Hydrated calcium silicate super fine powder strengthening rubber - Google Patents
Hydrated calcium silicate super fine powder strengthening rubber Download PDFInfo
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- CN100532440C CN100532440C CNB2007102000557A CN200710200055A CN100532440C CN 100532440 C CN100532440 C CN 100532440C CN B2007102000557 A CNB2007102000557 A CN B2007102000557A CN 200710200055 A CN200710200055 A CN 200710200055A CN 100532440 C CN100532440 C CN 100532440C
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Abstract
The present invention is superfine calcium silicate hydrate powder reinforced rubber and its production process. The materials consist of raw rubber 100 weight portions, zinc oxide 5 weight portion, sulfur 2.5 weight portions, stearic acid 1.5 weight portions, promoter 0.6 weight portions, and calcium silicate hydrate powder 30-60 weight portions. The calcium silicate hydrate powder is low crystallinity superfine powder prepared with quartz sand as the silica material and lime as the calcium material and through dynamic hydrothermal synthesis. The present invention adopts inexpensive calcium silicate hydrate powder to replace carbon black as rubber reinforcing stuffing, and the rubber product has breaking strength higher than that of carbon black rubber. Calcium silicate hydrate powder is white, so that the present invention may be used widely in producing color rubber products.
Description
(1) technical field
The present invention relates to a kind of rubber composite.
(2) background technology
Traditional rubber composite is generally by obtaining after rubber and the mixing sulfuration of filler auxiliary agent.Wherein rubber is a polymer moiety, mainly contains good plasticity and toughness, and filler mainly plays increase-volume, reinforcement, modification and make things convenient for effects such as technology.Filler commonly used is a carbon black, and carbon black is main reinforced filling in rubber, yet it is higher to add sooty rubber production cost, and curing time is longer, thus in the existing rubber industry with lime carbonate as compatibilization filler with the minimizing rubber material using quantity.Other compatibilization filler of having studied has flyash, super crushed quartz etc., but because technical reason, have the cost height, power consumption is big, dust pollution heavy, the characteristics of reinforcing effect difference, and can only cooperate carbon black to use, can not produce light-colour rubber, utilizing flyash, super crushed quartz to replace carbon black constantly has as the research and development of reinforced filling and appears in the newspapers, but success in production practice yet.
On the other hand, in the industrial production of silicate building material, the emphasis of people's concern at present is to steam to press under higher pressure to generate the higher hydrated calcium silicate of crystallization degree, as products such as Tobemolai stone, mirabilitum crystallina pomegranate stone, afwillites, think that its mechanical property is better, and at lower pressure, than the short very low hydrated product of constant voltage time hydro-thermal synthetic crystallization degree, as C-S-H gel, CSH (B) etc., do not obtain paying attention to and using.
(3) summary of the invention
The purpose of this invention is to provide a kind of hydrated calcium silicate super fine powder strengthening rubber, solution is applied in the rubber industry hydrated calcium silicate of the unsteady state of white as light inorganic reinforced filling, bring into play the double effects of its increase-volume and reinforcement, reduce production costs, reduce the energy consumption of powder production, the problem of reduction dust pollution.
The object of the present invention is achieved like this: this hydrated calcium silicate super fine powder strengthening rubber is characterized in that: its proportioning raw materials is calculated in mass,
Rubber: 100 parts;
Zinc oxide: 5 parts;
Sulphur: 2.5 parts;
Stearic acid: 1.5 parts;
Promotor: 0.6 part;
Hydration calcium silicate powder: 30 parts～60 parts;
Above-mentioned hydration calcium silicate powder is to be siliceous material with quartz sand, is calcareous material with unslaked lime, and the calcium silicon mol ratio is 1:1, and water-solid ratio is 5:1,, and the dry powder that form synthetic through dynamic hydro-thermal.
Above-mentioned rubber is natural rubber or styrene-butadiene rubber(SBR).
Above-mentioned promotor is dibenzothiazyl disulfide or tetraethylthiuram disulfide.
Also contain 1.5 parts of anti-aging agent in the above-mentioned raw materials component.
Above-mentioned anti-aging agent is 2 mercapto benzimidazole or 2-thiol group tolimidazole.
Also contain the surface-modifying agent that accounts for hydration calcium silicate powder total mass 1%～2% in the above-mentioned raw materials component.
Above-mentioned its surface-modifying agent is silane coupling agent, titante coupling agent or aluminium esters of gallic acid coupling agent.
The production method of above-mentioned hydrated calcium silicate super fine powder strengthening rubber is characterized in that production stage is as follows:
Step 1: prepare hydration calcium silicate powder earlier: is siliceous material with granularity at the quartz sand of 0.5～2.5 μ m, is calcareous material with granularity at the unslaked lime of 0.1～1.5 μ m, the calcium silicon mol ratio is 1: 1, water-solid ratio is 5: 1, the temperature that in reactor, keeps (100-120) ± 5 ℃, through intensification 2h, constant temperature 3h-10h, cooling, discharging, filtration,＜100 ℃ of dryings, obtain granularity hydrated calcium silicate between 0.1 μ m～0.5 μ m;
Step 2: high-speed stirring, hydrated calcium silicate is broken up to powdery, its block of conglomeration after taking off planar water is broken up, granularity is 0.9 ± 0.2 μ m;
Step 3: the surface modification of powder: get 100 parts of hydration calcium silicate powder and be placed in the ball mill, grinding made its temperature rise to 100 ℃-120 ℃ in ten minutes, adding with 100 parts of hydrated calcium silicate quality in ball mill then is 1～2 part of coupling agent and 0.7～0.8 part of stearic acid of benchmark, it is mixed and modified to carry out ball milling, total modification time is 8-12 minute, slowly be cooled to room temperature then, just can obtain the calcium silicate powder after the modification, its granularity is between 0.1 μ m～0.5 μ m;
Step 4: compound mixing: on rubber mixing machine, add raw material and carry out mixing, order of addition(of ingredients) is: the mixing rubber of elder generation, add stearic acid, zinc oxide, promotor, sulphur, hydration calcium silicate powder then successively, and play the triangle bag afterwards and evenly refine glue, return thickly at last, become mixed sheet;
Step 5: sulfuration: mixed sheet is parked postcure in 24 hours, rubber unvulcanizate is placed on the template, and be clipped on the vulcanizer and vulcanize, and cure conditions is 160 ± 5 ℃, 2～4min, and sulfuration can obtain hydrated calcium silicate super fine powder strengthening rubber after finishing.
Above-mentioned steps 3 can be omitted.
In the above-mentioned steps 4, the roll spacing in rubber mixing machine mixing when beginning is 3-5mm, regulates being reduced to 1-3mm then gradually; The roller speed ratio is 1.1-1.5:1; The roller temperature control is below 50 ℃, and mixing time is 20-30min.
The present invention compares the beneficial effect that has with existing conventional art: the present invention fills the ultra-fine hydration calcium silicate powder of white with filler as reinforcement, replace the carbon black in the rubber, the basically identical of the tensile strength at yield of the rubber combined material of gained, tearing toughness and N220 black rubber, pull apart unit elongation and obviously improve, so this powder can be as the reinforcing filler of light-colour rubber.This class silicate powder particulate alkalescence of synthetic is higher, and it is 12 that the filtered water when going out still is tested pH, has the tart white carbon black with the surface and compares with potter's clay, has significantly reduced curing time, reduces energy consumption, can also reduce the consumption of promotor simultaneously.Because hydration calcium silicate powder is a white, therefore can be widely used in the colored rubber goods.
The reinforcement mechanism of hydration calcium silicate powder of the present invention: select for use the quartz sand that extensively is easy to get as raw material, adopt dynamic hydro-thermal synthesis process, make quartz sand under hydrothermal condition, rigid shell is broken, SiO2 is dissolved in the solution, silicon-oxy tetrahedron depolymerization, hydrolysis produce activated silica, are easier to and alkaloids water generation reaction Calucium Silicate powder (C-S-H) such as unslaked lime.Through intensification, constant temperature, cooling, discharging, filtration, drying, make ultra-fine, porous, bigger serface, unformed dendritic nanometer hydration calcium silicate powder.Become powder filled mutual winding, parcel and the closely knit effect mutually mutually of can producing in the macromolecular chain of rubber of dendritic hydrated silicate, can remedy rubber because of the deficiency of space molecular chain unbalance stress when the tension is arranged, can be when mutual closely knit back forms the rubber tension of integration with the stress slippage, marry again, relaxed the degree of irregularity of stress, avoided stress concentration, so help the reinforcement of rubber; Synthetic hydrated silicate powder in addition, it contains a large amount of crystal water, there is part free OH-existence on the surface, in the time of 160 ℃ can with some functional groups dehydration mortise in the rubber polymer, can be for the part hydrophilic radical by surface modification to promote wettability to rubber.
Filler of the present invention adopts the very wide starting material in source of safety non-toxic, utilizes more weak steaming compacting degree, and promptly lower pressure, the constant voltage time of lacking produce the bad gelatinous hydrated calcium silicate of mass crystallization, compares with production of carbon black to help protecting environment.Through experimental results show that with modern test method such as X diffraction analysis instrument XRD, nitrogen adsorption method BET, transmission electron microscope TEM, scanning electron microscope sem, tunnel scanning electron microscope STM:
(a), pass through hydro-thermal synthesis process, steaming pressure 10h down at 120 ℃ constant temperature and pressures (pressure is 0.198MPa) can obtain than bigger serface porous hydration calcium silicate powder, by the transmissioning electric mirror test analysis, the powder crystal granularity is minimum, can reach nano level; The TEM image shows that powder is the granuloplastic loose aggregates about 50nm, has estimated the grain fineness number size by the Scherrer formula, and granularity is between 40～60nm.
(b), logical X diffraction analysis instrument XRD, find that powder degree of crystallinity is low, mostly be unformed shape.
(c), by the observation of scanning electron microscope sem, tunnel scanning electron microscope STM, referring to Fig. 6, Fig. 7, finding has good consistency with sizing material, good dispersity in base-material (sizing material), the similar black rubber of its characteristic pattern after the hydration calcium silicate powder modification.
Fig. 4, Fig. 5 are the test-results of curing time to rubbery intensity influence of the present invention, adopt aluminium esters of gallic acid coupling agent as surface-modifying agent among Fig. 4, adopt another kind of aluminium esters of gallic acid coupling agent as surface-modifying agent among Fig. 5.Proof curing time rubbery intensity in 2-4 minute scope is the highest.
Each performance of the present invention and the correlated test result of black rubber:
Ultra-fine hydration calcium silicate powder (be meant by quartz sand and unslaked lime and do raw material) with 10h in the prepared ultra-fine hydration calcium silicate powder of the dynamic hydro-thermal reaction constant temperature of autoclave back warp 10h, volume is 40% (mass percent) of sizing material, through after the modification of properties-correcting agent, cure conditions is controlled at 160 ℃ * 3min, the effect of made rubber composite is best, and its The performance test results and N220 black rubber performance comparison are as follows:
Table 1 silane SG-Si900 modification aquation silicate powder and the performance test of natural rubber composite wood
| Powder volume (% sizing material) | 30 | 40 | 50 | 60 | 0 (50 parts of N220 carbon blacks) |
| Tensile strength at yield (MPa) | 12.8 | 14.4 | 13.7 | 12.7 | 14.5 |
| Tensile yield | 660 | 680 | 640 | 560 | 580 |
| Tear strength (MPa) | 18.6 | 23.7 | 20.2 | 18.1 | 24.6 |
| Shore hardness | 41 | 43 | 46 | 48 | 48 |
Table 2 aluminic acid lipoprotein 501 modification aquation silicate powders and the performance test of natural rubber composite wood
| Powder volume (% sizing material) | 30 | 40 | 50 | 60 | 0 (50 parts of N220 carbon blacks) |
| Tensile strength at yield (MPa) | 14.3 | 14.6 | 14.2 | 12.1 | 14.5 |
| Tensile yield | 740 | 720 | 700 | 620 | 580 |
| Tear strength (MPa) | 18.0 | 23.7 | 20.2 | 19.3 | 24.6 |
| Shore hardness | 41 | 43 | 45 | 48 | 48 |
Table 3 metatitanic acid fat TM-27 modification aquation silicate powder and the performance test of natural rubber composite wood
| Powder volume (% sizing material) | 30 | 40 | 50 | 60 | 0 (50 parts of N220 carbon blacks) |
| Tensile strength at yield (MPa) | 14.2 | 14.5 | 13.7 | 13.2 | 14.5 |
| Tensile yield | 740 | 700 | 660 | 640 | 580 |
| Tear strength (MPa) | 19.6 | 23.2 | 18.2 | 18.0 | 24.6 |
| Shore hardness | 39 | 42 | 45 | 48 | 48 |
Table 4 501 modified powders/rubber composite test data
Table 5 502 modified powders/rubber composite test data
(5) sulfuration: film is parked postcure in 24 hours, rubber unvulcanizate is placed on the template, and be clipped on the vulcanizing press.Adopt certain cure conditions to vulcanize.Sulfuration can obtain the rubber composite that hydration calcium silicate powder is a reinforcing filler after finishing.Cure conditions is 160 ℃ * 3min.Promptly get final rubber composite at last.This composite wood and black rubber mechanical property basically identical.The exploitation of this light filler can replace traditional reinforced filling carbon black, will bring revolutionary progress to rubber industry.
(4) description of drawings
Fig. 1 is the process flow sheet of hydrated calcium silicate super fine powder strengthening rubber production method of the present invention.
Fig. 2 is the technological process of production figure of hydration calcium silicate powder.
Fig. 3 is the process flow sheet of hydration calcium silicate powder modification.
Fig. 4 is the graphic representation that the intensity of a kind of hydrated calcium silicate super fine powder strengthening rubber of the present invention changes with curing time.
Fig. 5 is the graphic representation that the intensity of the another kind of hydrated calcium silicate super fine powder strengthening rubber of the present invention changes with curing time.
Fig. 6 is that carbon black disperses compatible STM tunnel sem photograph in rubber.
Fig. 7 is that hydration calcium silicate powder is disperseed compatible STM tunnel sem photograph in rubber.
(5) embodiment
The proportioning embodiment of hydrated calcium silicate super fine powder strengthening rubber of the present invention is as follows: is benchmark than the component of content with the 100g rubber by quality:
Rubber: 100g;
Zinc oxide: 5g;
Sulphur: 2.5g;
Stearic acid: 1.5g;
Promotor: 0.6g;
Hydration calcium silicate powder: any number between 30g～60g.
Above-mentioned rubber is meant natural rubber or styrene-butadiene rubber(SBR) etc.For example: natural rubber.
Above-mentioned promotor is dibenzothiazyl disulfide or tetraethylthiuram disulfide.
Also contain the surface-modifying agent that accounts for hydration calcium silicate powder total mass 1%～2% in the above-mentioned raw materials component, its surface-modifying agent can be selected silane coupling agent, titante coupling agent, aluminium esters of gallic acid coupling agent or other similar substance.
Can also contain the 1.5g anti-aging agent in the above-mentioned hydrated calcium silicate super fine powder strengthening rubber, can adopt antioxidant MB or MMB, be i.e. 2-thiol group benzimidazolyl or 2-thiol group tolimidazole.Also can adopt other similar substance.
Above-mentioned hydration calcium silicate powder is to be siliceous material with quartz sand, is calcareous material with unslaked lime, and calcium silicon is 1: 1 than (mol ratio), and water-solid ratio is 5: 1, synthetic through hydro-thermal in reactor, and the dry powder that forms.
The production method embodiment of hydrated calcium silicate super fine powder strengthening rubber of the present invention is referring to shown in Figure 1:
(1), earlier prepare hydration calcium silicate powder, the proportioning example is as follows:
With the quartz sand siliceous material, its SiO2 content 97.2%, the consumption 4.1kg of quartz sand.
With the unslaked lime that originates in Nikkei mountain, Chongqing is calcareous material, and the free CaO content of lime is 85.1%, lime consumption 4.4kg.
The consumption of water is 42.5kg, and the starting material total mass is 8.5kg, and calcium silicon is 1: 1 than CaO:SiO2 (mol ratio), and water-solid ratio is 5: 1, and said ratio can be adjusted according to selecting raw-material difference for use, and this adjustment technology belongs to those skilled in the art's known technology.
Referring to Fig. 2, said components is kept the temperature of (110) ± 5 ℃ in reactor, through intensification 2h, constant temperature 3h-10h, cooling 4h, discharging, filtration, and dry to constant weight in the temperature below 100 ℃, dynamically the synthetic hydration calcium silicate powder of hydro-thermal is standby.
(2), referring to Fig. 3, hydration calcium silicate powder is broken up powder through high-speed stirring, and powder is preheated to 50～60 ℃.
(3), the surface modification of powder: take by weighing the 100g hydration calcium silicate powder and be placed in the ball mill, grinding made its temperature rise to about 110 ℃ in ten minutes, (total volume is 1% with aluminium esters of gallic acid coupling agent, and add 0.75% stearic acid and mix with it) add ball mill and carry out the dry ball milling modification, total modification time is 10 minutes, slowly be cooled to the calcium silicate powder after room temperature just can obtain modification then, its granularity is between 0.1 μ m～0.5 μ m.
(4), compound mixing: carry out mixingly on X (S) K-250 opening rubber mixing machine, order of addition(of ingredients) is: when adopting the mixing beginning of rubber mixing machine, roll spacing is 3-5mm, is reduced to 1-3mm then gradually; The roller speed ratio is 1.1-1.5:1, fast roller after.The roller temperature control is below 50 ℃, to prevent incipient scorch.According to the difficulty or ease of fillers dispersed, mixing time is 20-30min.Reinforced order is: with the mixing natural rubber rubber of rubber mixing machine, add stearic acid, zinc oxide, altax, sulphur, filler then successively earlier, beat " triangle bag " (this is evenly to refine a procedure that must adopt in the glue, returns thick at last) afterwards.
(5) sulfuration: film is parked postcure in 24 hours, rubber unvulcanizate is placed on the template, and be clipped on the vulcanizing press.Adopt certain cure conditions to vulcanize.Sulfuration can obtain the rubber composite that hydration calcium silicate powder is a reinforcing filler after finishing.Cure conditions is 160 ℃ * 3min.Promptly get final rubber composite at last.This composite wood and black rubber mechanical property basically identical.
Claims (6)
- [claim 1] a kind of hydrated calcium silicate super fine powder strengthening rubber is characterized in that: its proportioning raw materials is calculated in mass,Rubber: 100 parts;Zinc oxide: 5 parts;Sulphur: 2.5 parts;Stearic acid: 1.5 parts;Promotor: 0.6 part;Hydration calcium silicate powder: 30 parts～60 parts;Above-mentioned hydration calcium silicate powder is to be siliceous material with quartz sand, is calcareous material with unslaked lime, and the calcium silicon mol ratio is 1: 1, and water-solid ratio is 5: 1,, and the dry powder that form synthetic through dynamic hydro-thermal;Also contain the surface-modifying agent that accounts for hydration calcium silicate powder total mass 1%～2% in the described feed composition.
- [claim 2] hydrated calcium silicate super fine powder strengthening rubber according to claim 1 is characterized in that: described rubber is natural rubber or styrene-butadiene rubber(SBR).
- [claim 3] hydrated calcium silicate super fine powder strengthening rubber according to claim 1 is characterized in that: described promotor is dibenzothiazyl disulfide or tetraethylthiuram disulfide.
- [claim 4] is characterized in that according to each described hydrated calcium silicate super fine powder strengthening rubber of claim 1 to 3: also contain 1.5 parts of anti-aging agent in the described feed composition.
- [claim 5] hydrated calcium silicate super fine powder strengthening rubber according to claim 4 is characterized in that: described anti-aging agent is 2 mercapto benzimidazole or 2-thiol group tolimidazole.
- [claim 6] hydrated calcium silicate super fine powder strengthening rubber according to claim 4 is characterized in that: described surface-modifying agent is silane coupling agent, titante coupling agent or aluminium esters of gallic acid coupling agent.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101775218B (en) * | 2009-12-31 | 2012-07-25 | 重庆大学 | High-temperature vulcanized silicon rubber and fast preparation method thereof |
| CN103131066A (en) * | 2013-03-20 | 2013-06-05 | 中国矿业大学(北京) | Active calcium silicate/rubber composite material and preparation method thereof |
| CN107686118B (en) * | 2017-08-23 | 2020-07-28 | 内蒙古普诺思新材料科技有限公司 | Method for preparing calcium silicate powder by liquid-phase dynamic hydrothermal synthesis method |
| CN108945956A (en) * | 2018-08-01 | 2018-12-07 | 浙江耐者胶带有限公司 | A kind of oil resistant conveyer |
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