WO1996030302A1 - Nouveau procede de preparation de silice precipitee, nouvelles silices precipitees contenant du zinc et leur utilisation au renforcement des elastomeres - Google Patents
Nouveau procede de preparation de silice precipitee, nouvelles silices precipitees contenant du zinc et leur utilisation au renforcement des elastomeres Download PDFInfo
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- WO1996030302A1 WO1996030302A1 PCT/FR1996/000462 FR9600462W WO9630302A1 WO 1996030302 A1 WO1996030302 A1 WO 1996030302A1 FR 9600462 W FR9600462 W FR 9600462W WO 9630302 A1 WO9630302 A1 WO 9630302A1
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- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
- C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
- C09C1/28—Compounds of silicon
- C09C1/30—Silicic acid
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- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/113—Silicon oxides; Hydrates thereof
- C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
- C01B33/18—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof
- C01B33/187—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof by acidic treatment of silicates
- C01B33/193—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof by acidic treatment of silicates of aqueous solutions of silicates
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- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
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Definitions
- the present invention relates to a new process for the preparation of precipitated silica, precipitated silicas in particular in the form of powder, substantially spherical beads or granules, and their application as a reinforcing filler for elastomers. It is known that precipitated silica has been used for a long time as a reinforcing white filler in elastomers.
- the filler has a very good ability to be incorporated into the matrix during mixing with the elastomer (incorporability of the filler) and to disintegrate or disintegrate in the form of a very fine powder (charge disaggregation), and where, on the other hand, the powder resulting from the abovementioned disintegration process can itself, in turn, disperse perfectly and homogeneously in the elastomer (dispersion of the powder).
- silica particles have an unfortunate tendency, in the elastomer matrix, to agglomerate with one another.
- the negative consequence of these silica / silica interactions is to limit the reinforcement properties to a level substantially lower than that which it would theoretically be possible to achieve if all the silica / elastomer interactions capable of being created during the mixing operation, were actually obtained (this theoretical number of silica / elastomer interactions being, as is well known, directly proportional to the external surface, of the silica used).
- silica / silica interactions tend, in the raw state, to increase the stiffness and the consistency of the mixtures, thus making their use more difficult.
- the present invention aims to overcome the aforementioned drawbacks and to solve the above-mentioned problem.
- the invention also relates to precipitated silicas which, preferably, are in the form of powder, substantially spherical beads or, optionally, granules, and which, while having a relatively large size, have very satisfactory reinforcing properties and, preferably, a very good dispersibility (and deagglomeration) ability.
- the CTAB specific surface is the external surface determined according to standard NFT 45007 (November 1987) (5.12).
- the DOP oil intake is determined according to standard NFT 30-022 (March 1953) using dioctylphthalate.
- the density of filling in the packed state is measured according to standard NFT-030100.
- the pH is measured according to ISO standard 787/9 (pH of a 5% suspension in water).
- the ability to disperse and deagglomerate the silicas according to the invention can be quantified by means of a specific deagglomeration test.
- the disagglomeration test is carried out according to the following protocol: the cohesion of the agglomerates is assessed by a particle size measurement
- the deagglomeration under ultrasound is carried out using a VIBRACELL BIOBLOCK sonicator (600 W), equipped with a 19 mm diameter probe.
- the particle size measurement is carried out by laser diffraction on a SYMPATEC granulometer.
- the value of the median diameter 0 ⁇ that is obtained is lower the higher the silica has a high deagglomeration capacity.
- the ratio (10 ⁇ volume of suspension introduced (in ml)) / optical density of the suspension detected by the granulometer is also determined (this optical density is of the order of 20). This report is indicative of the rate of fines, that is to say the rate of particles smaller than 0.1 ⁇ m which are not detected by the granulometer.
- This ratio called ultrasound disaggregation factor (Fr j ), is all the higher as the silica has a high disaggregation ability.
- One of the objects of the invention is a process for the preparation of precipitated silica of the type comprising the reaction of a silicate with an acidifying agent, whereby a suspension of precipitated silica is obtained, then the separation and drying of this suspension, in which the precipitation is carried out as follows:
- step (a) adding, after step (iii), to the reaction medium at least one zinc compound, then a basic agent, and, when said separation involves filtration and disintegration of the cake resulting from this filtration, said disintegration is preferably carried out in the presence of at least one aluminum compound,
- step (b) a silicate and at least one zinc compound are added to the reaction medium simultaneously after step (iii) and, when said separation comprises a filtration and disintegration of the cake resulting from this filtration, the disintegration is preferably carried out in the presence of at least one aluminum compound.
- the process concerned is a process for the synthesis of precipitation silica, that is to say that an acidifying agent is made to act, under very specific conditions. silicate.
- a strong mineral acid such as sulfuric acid, nitric acid or hydrochloric acid, or an organic acid such as acetic acid, formic acid or l 'carbonic acid.
- the acidifying agent can be diluted or concentrated; its normality can be between 0.4 and 36 N, for example between 0.6 and 1.5 N.
- the acidifying agent is sulfuric acid
- its concentration can be between 40 and 180 g / l, for example between 60 and 130 g / l.
- silicate any common form of silicates such as metasilicates, disilicates and advantageously an alkali metal silicate, in particular sodium or potassium silicate.
- the silicate may have a concentration expressed as silica of between 40 and 330 g / l, for example between 60 and 300 g / l, in particular between 60 and 250 g / l.
- sulfuric acid is used as the acidifying agent
- sodium silicate as the silicate.
- sodium silicate In the case where sodium silicate is used, it generally has a weight ratio SIO j / Na ⁇ of between 2 and 4, for example between 3.0 and 3.7. With regard more particularly to the process for the preparation of the invention, the precipitation takes place in a specific manner according to the following steps.
- a base stock which comprises silicate as well as an electrolyte (step (i)).
- the quantity of silicate present in the initial base stock advantageously represents only a part of the total quantity of silicate used in the reaction.
- electrolyte is understood here in its normal acceptance, that is to say it means any ionic or molecular substance which, when in solution, decomposes or dissociates to form ions or charged particles. . Mention may be made, as electrolyte, of a salt from the group of alkali and alkaline earth metal salts, in particular the salt of the starting silicate metal and of the acidifying agent, for example sodium sulfate in the case of the reaction of a sodium silicate with sulfuric acid.
- the electrolyte concentration in the initial base stock is (greater than 0 g / l and) less than 17 g / l, preferably less than 14 g / l.
- the silicate concentration in the initial base stock is (greater than 0 g / l and) less than 100 g of Si0 2 per liter.
- this concentration is less than 90 g / l, especially 85 g / l. It can in some cases be less than 80 g / l.
- the second step consists in adding the acidifying agent to the base stock of the composition described above (step (ii)). This addition, which results in a corresponding drop in the pH of the reaction medium, takes place until a pH value of at least about 7 is reached, generally between 7 and 8.
- step (iii)) of acidifying agent and silicate is carried out.
- This simultaneous addition is preferably carried out in such a way that the pH value is constantly equal (to within +/- 0.1) to that reached at the end of step (ii).
- the preparation process according to the invention comprises one of the two operations (a) or (b) mentioned above, that is to say:
- step (b) adding, after step (iii), simultaneously to the reaction medium a silicate and at least one zinc compound and, when the separation, used in the process, involves filtration and disintegration of the cake from this filtration, the disintegration is preferably carried out in the presence of at least one aluminum compound.
- the precipitation is advantageously carried out after having carried out the precipitation according to steps (i), ( ii) and (iii) previously described, the following successive steps:
- a basic agent is added to the reaction medium, preferably until a pH value of the reaction medium of between 7.4 and 10, in particular between 7.8 and 9, is obtained,
- acidifying agent is added to the reaction medium, preferably until a pH value of the reaction medium of at least 7, in particular between 7 and 8.5, for example between 7 and 8.
- stage (iii) it may then be advantageous to carry out, after the simultaneous addition of stage (iii), a maturing of the reaction medium, this maturing being able for example to last from 1 to 60 minutes, in particular from 3 to 30 minutes.
- step (iii) and step (iv) it may be desirable, between step (iii) and step (iv), and in particular before said possible ripening, to add to the medium reaction an additional amount of acidifying agent.
- This addition is generally carried out until a pH value of the reaction medium of between 3 and 6.5, in particular between 4 and 6, is obtained.
- the acidifying agent used during this addition is generally identical to that used during steps (ii), (iii) and (vi) of the first variant of the preparation process according to the invention.
- the reaction medium is usually matured between step (v) and step (vi), for example for 2 to 60 minutes, in particular for 5 to 45 minutes.
- a ripening of the reaction medium is most often carried out after step (vi), for example for 2 to 60 minutes, in particular for 5 to 30 minutes.
- the basic agent used during step (iv) can be an ammonia solution or, preferably, a sodium hydroxide solution (or soda).
- a step (iv) which consists in adding simultaneously to the reaction medium a silicate and at least one zinc compound. It may then be advantageous to carry out, after the simultaneous addition of step (iv), a maturing of the reaction medium, this maturing being able for example to last from 2 to 60 minutes, in particular from 5 to 30 minutes.
- step (iv) it may be desirable, after step (iv), and in particular after this possible ripening, to add to the reaction medium an additional amount of acidifying agent.
- This addition is generally carried out until a pH value of the reaction medium of at least 7 is obtained, in particular between 7 and 8.5, for example between 7 and 8.
- the acidifying agent used during this addition is generally identical to that used during steps (ii) and (iii) of the second variant of the preparation process according to the invention.
- the reaction medium is usually matured after this addition of acidifying agent, for example for 1 to 60 minutes, in particular for 3 to 30 minutes.
- the zinc compound used in the preparation process according to the invention is generally an organic or inorganic zinc salt.
- organic salt mention may in particular be made of the salts of carboxylic or polycarboxylic acids, such as the salts of acetic, citric, tartaric or oxalic acid.
- inorganic salt mention may in particular be made of halides and oxyhalides (such as chlorides, oxychlorides), nitrates, phosphates, sulfates and oxysulfates.
- the zinc compound can be used in the form of a solution, generally aqueous.
- zinc sulfate is used as the zinc compound.
- the temperature of the reaction medium is generally between 70 and 98 ° C.
- the reaction is carried out at a constant temperature between 75 and 96 ° C.
- the temperature at the end of the reaction is higher than the temperature at the start of the reaction: thus, the temperature at the start of the reaction is maintained preferably between 70 and 96 ° C., then the temperature is increased in a few minutes, preferably to a value between 80 and 98 ° C, value at which it is maintained until the end of the reaction; operations (a) or (b) are thus usually carried out at this constant temperature value.
- this separation generally comprises filtration (followed by washing if necessary) and disintegration, said disintegration preferably being carried out in presence of at least one aluminum compound and, preferably, in the presence of an acidifying agent as described above (in the latter case, the aluminum compound and the acidifying agent are advantageously added simultaneously ).
- the separation also generally comprises filtration (followed by washing if necessary) and a disintegration, said disintegration preferably being carried out in the presence of at least one aluminum compound and, in general, in the presence of an acidifying agent as described above (in the latter case, the compound of l aluminum and the acidifying agent are advantageously added simultaneously).
- the aluminum compound generally consists of an alkali metal aluminate, in particular potassium or, very preferably, sodium.
- the amount of zinc compound used in the preparation process according to the invention is such that the precipitated silica prepared contains between 1 and 5%, in particular between 1, 5 and 4%, for example between 1, 5 and 2.5%, by weight of zinc.
- the separation implemented in the preparation process according to the invention usually comprises a filtration carried out by means of any suitable method, for example by means of a belt filter, a rotary vacuum filter or, preferably, 'a filter press.
- the precipitated silica suspension thus recovered (filtration cake) is then dried.
- this suspension must present immediately before its drying a dry matter content of at most 24% by weight, preferably at most 22% by weight.
- This drying can be done by any means known per se.
- the drying is carried out by atomization.
- any suitable type of atomizer can be used, in particular a turbine, nozzle, liquid pressure or two-fluid atomizer.
- the suspension to be dried has a dry matter content greater than 15% by weight, preferably greater than 17% by weight and, for example, greater than 20% by weight.
- the drying is then preferably carried out by means of a nozzle atomizer.
- the precipitated silica capable of being obtained according to this embodiment of the invention and preferably by using a filter press is advantageously in the form of substantially spherical beads, preferably with an average size of at least 80 ⁇ m .
- a grinding step can be carried out on the product recovered, in particular on the product obtained by drying a suspension having a dry matter content greater than 15% by weight.
- the precipitated silica which can then be obtained is generally in the form of a powder, preferably of average size of at least 15 ⁇ m, in particular between 15 and 60 ⁇ m, for example between 20 and 45 ⁇ m.
- the products ground to the desired particle size can be separated from any non-conforming products by means, for example, of vibrating screens having appropriate mesh sizes, and the non-conforming products thus recovered be returned to grinding.
- the suspension to be dried has a dry matter content of at most 15% by weight. The drying is then generally carried out by means of a turbine atomizer.
- the precipitated silica which can then be obtained according to this embodiment of the invention and preferably by using a rotary vacuum filter is generally in the form of a powder, preferably of medium size. at least 15 ⁇ m, in particular between 30 and 150 ⁇ m, for example between 45 and 120 ⁇ m.
- the dried (in particular from a suspension having a dry matter content of at most 15% by weight) or ground product can, according to another embodiment of the invention, be subjected to a stage of agglomeration.
- Agglomeration is understood here to mean any process which enables finely divided objects to be linked together so as to bring them in the form of objects of larger size and more mechanically resistant. These processes include direct compression, wet granulation (i.e. with the use of a binder such as water, silica slurry, ...), extrusion and, preferably, compaction at dry.
- the precipitated silica capable of being obtained according to this embodiment of the invention is advantageously in the form of granules, preferably of size at least 1 mm, in particular between 1 and 10 mm.
- the products can be calibrated to a desired size, for example by sieving, then packaged for their future use.
- the powders, as well as the beads, of precipitated silica obtained by the process according to the invention thus offer the advantage, among other things, of having simple, effective and economical access to granules as mentioned above, in particular by operations conventional shaping, such as for example granulation or compaction, without the latter causing degradation capable of masking, or even annihilating, the good intrinsic properties attached to these powders or these beads, as may be the case in the prior art by using conventional powders.
- CTAB specific surface of between 90 and 250 m 2 / g, for example between 120 and 230 m 2 / g,
- a BET specific surface area between 90 and 250 m 2 / g, for example between 120 and 240 m 2 / g, - a DOP oil intake of less than 300 ml / 100g, preferably between 200 and 295 ml / 100g ,
- the silica according to the invention preferably has a zinc content of between 1.5 and 4% by weight; this content can be in particular between 1.5 and 2.5% by weight.
- One of the essential characteristics of the precipitated silica according to the invention is its consumption, in a model medium (xylene), of an ingredient for vulcanizing rubber (stearic acid).
- IR infrared spectrometry
- the flask is then placed under magnetic stirring for 105 min. Then the stirring is stopped and the flask is still left in the oil bath for 15 minutes. The total duration of the reaction at 120 ° C. is therefore 2 hours. The refrigerant is removed and the flask is removed from the oil bath.
- the contents of the flask are filtered on a microfiltration system (MILLIPORE assembly with filters with DURAPORE membranes made of polyvinylidene fluoride (pore size: 0.45 ⁇ m)).
- MILLIPORE assembly with filters with DURAPORE membranes made of polyvinylidene fluoride (pore size: 0.45 ⁇ m) The contents of the flask are filtered on a microfiltration system (MILLIPORE assembly with filters with DURAPORE membranes made of polyvinylidene fluoride (pore size: 0.45 ⁇ m)).
- the IR spectrum of solution S is produced.
- the value of the characteristic peak of stearic acid reduced to the equation of the calibration line makes it possible to determine the level of stearic acid present in solution S; taking into account the mass of xylene added during dilution, the level of stearic acid in the reaction filtrate is obtained.
- the level and therefore the amount of stearic acid consumed by the silica during the reaction is deduced from the initial stearic acid level and the stearic acid level after reaction (the latter being the stearic acid level of the filtrate ).
- the number N of stearic acid molecules consumed per nm 2 of surface of the silica is then determined.
- the zinc contained in the precipitated silica according to the invention is not, preferably, in crystallized form, but rather occurs in amorphous form (this can be determined by X-ray diffraction).
- the precipitated silica has: - a CTAB specific surface of between 90 and 185 m 2 / g, in particular 120 and 185 m 2 / g, for example between 140 and 180 m 2 / g, - a median diameter 0 ⁇ ), after deagglomeration with ultrasound, less than 4 ⁇ m, preferably less than 3 ⁇ m,
- the median diameter &), after ultrasonic deagglomeration, of the precipitated silica according to this variant of the invention may be less than 2.8 ⁇ m, for example less than 2.5 ⁇ m.
- the ultrasound deagglomeration factor (Fp) of the precipitated silica according to this variant of the invention may be greater than 11 ml, for example greater than 14 ml.
- the BET specific surface of the precipitated silica according to this variant of the invention is generally between 90 and 195 m 2 / g, in particular between 120 and 195 m 2 / g, for example between 150 and 190 m 2 / g.
- the precipitated silica has: - a CTAB specific surface greater than 185 m / g and less than
- the median diameter (0 ⁇ ), after ultrasonic deagglomeration, of the precipitated silica according to this variant of the invention can be less than 4 ⁇ m.
- the ultrasound deagglomeration factor (Fp) of the precipitated silica according to this variant of the invention may be greater than 6 ml.
- the BET specific surface area of the precipitated silica according to this variant of the invention is generally between 185 and 230 m 2 / g.
- one of the characteristics of silica can also reside in the distribution, or distribution, of the pore volume, and in particular in the distribution of the pore volume which is generated by the pores of smaller or equal diameters. at 400 A. This last volume corresponds to the useful pore volume of the fillers which are used in the reinforcement of the elastomers.
- the silica according to a particular mode of the invention has a porous distribution such that the pore volume constituted by the pores whose diameter is between 175 and 275 A represents at least 50%, for example at least 60%, of the pore volume constituted by the pores of diameters less than or equal to 400 ⁇ .
- the silica has a BET specific surface / CTAB specific surface ratio of between 1.0 and 1.2, that is to say it preferably has a low microporosity.
- the pH of the silica according to the invention is generally between 8.0 and 9.0, for example between 8.3 and 8.9.
- the silicas according to the invention can be in the form of powder, substantially spherical beads or, optionally, granules and are in particular characterized by the fact that, while having a relatively large size, they have very satisfactory reinforcing properties and, preferably, excellent ability to disperse and disagglomerate. They can thus thus have an advantageously greater dispersibility and disaggregation capacity, with the same or similar specific surface and with identical or similar size, than that of the silicas of the prior art.
- the silica powders according to the invention preferably have an average size of at least 15 ⁇ m; this is for example between 15 and 60 ⁇ m (in particular between 20 and 45 ⁇ m) or between 30 and 150 ⁇ m (in particular between 45 and 120 ⁇ m). They preferably have a DOP hulia plug of between
- the filling density in the packed state (DRT) of said powders is, in general, at least 0.17, and, for example, between 0.2 and 0.3.
- Said powders generally have a total pore volume of at least 2.5 cm 3 / g, and more particularly between 3 and 5 cm 3 / g.
- the substantially spherical beads according to the invention preferably have an average size of at least 80 ⁇ m.
- this average size of the beads is at least 100 ⁇ m, for example at least 150 ⁇ m; it is generally at most 300 ⁇ m and is preferably between 100 and 270 ⁇ m.
- This average size is determined according to standard NF X 11507 (December 1970) by dry sieving and determination of the diameter corresponding to a cumulative refusal of 50%.
- They preferably have a DOP hulia intake of between 240 and 290 ml / 100 g.
- the filling density in the packed state (DRT) of said balls (or pearls) is, in general, at least 0.17, and, for example, between 0.2 and 0.34.
- Such silica in the form of substantially spherical beads, advantageously full, homogeneous, little dusty and of good flowability, preferably has a very good ability to disagglomerate and to disperse. In addition, it has good reinforcing properties.
- Such silica also constitutes a preferred precursor for the synthesis of the powders and granules according to the invention.
- silica in the form of substantially spherical beads constitutes a very advantageous variant of the invention.
- the dimensions of the granules according to the invention are preferably at least 1 mm, in particular between 1 and 10 mm, along the axis of their largest dimension (length).
- They preferably have a DOP hulia intake of between 200 and 260 ml / 100 g.
- Said granules can be in the most diverse forms.
- the packed filling density (DRT) of said granules is generally at least 0.27 and can range up to 0.37. They generally have a total pore volume of at least 1 cm 3 / g, and more particularly between 1.5 and 2 cm 3 / g.
- silicas according to the invention in particular in the form of powder, substantially spherical beads or granules, are preferably prepared according to one of the appropriate variants of the preparation process according to the invention and described above.
- the silicas according to the invention or prepared by the process according to the invention find a particularly advantageous application in the reinforcement of elastomers, natural or synthetic. They give these elastomers excellent rheological properties while providing them with good mechanical properties and, in general, good abrasion resistance. In addition, these elastomers are then preferably subject to reduced heating.
- the invention therefore also relates to the use of these silicas to improve the rheological properties (illustrated, for example, by the consistency MOONEY, the minimum torque) of the elastomers.
- the following examples illustrate the invention without, however, limiting its scope.
- EXAMPLE 1 (comparative) A silica is prepared (referenced A1) in accordance with Example 12 of European patent application EP-A-0520862 (filing number 92401677.7).
- the characteristics of the silica obtained A1 in the form of substantially spherical beads are as follows:
- V1 represented by the pores of d ⁇ 400 A 0.90 cm 3 / g
- V2 represented by the pores 175 ⁇ ⁇ d ⁇ 275 A 0.55 cm 3 / g - ratio V2 ⁇ 1 61%
- the number N of stearic acid molecules consumed per nm 2 of silica surface, when stearic acid is reacted with said silica A1 in xylene for 2 hours at 10 ° C. is equal to 0.5.
- the silica A1 is subjected to the deagglomeration test as defined previously in the description. After deagglomeration with ultrasound, it has a median diameter
- Si ⁇ 2 / Na 2 0 equal to 3.45 and a density at 20 ° C equal to 1.230.
- the silicate concentration expressed as Si0 2 in the initial base stock is then 79 g / l.
- the mixture is then brought to a temperature of 80 ° C. while keeping it under agitation. Then there is introduced, at a flow rate of 7.0 l / min, dilute sulfuric acid with a density at 20 ° C equal to 1.050 until a pH value is obtained in the reaction medium (measured at its temperature ) equal to 8.0.
- the reaction temperature is 80 ° C for the first 30 minutes; it is then brought from 80 to 94 ° C in about 15 minutes, then maintained at 94 ° C until the end of the reaction.
- an aqueous solution containing 180 g / l of sodium hydroxide is introduced into the reaction medium, until the pH of the reaction medium is equal to 8.0.
- the introduction of acid is then stopped and the reaction medium is cured for 5 minutes at a temperature of 94 ° C.
- the total duration of the reaction is 128 minutes.
- a precipitated silica slurry or suspension is thus obtained which is then filtered and washed using a filter press.
- the cake obtained is then fluidized by mechanical and chemical action (simultaneous addition of sulfuric acid and an amount of sodium aluminate corresponding to a weight ratio Al / Si0 2 of 0.20%). After this disintegration operation, the resulting slurry, pH equal to 8.4 and loss on ignition equal to 78.0% (therefore a dry matter content of 22.0% by weight), is atomized by means of a nozzle atomizer.
- V1 represented by the pores of d ⁇ 400 ⁇ 0.92 cm 3 / g
- V2 represented by the pores 175 ⁇ ⁇ d ⁇ 275 ⁇ 0.47 cm 3 / g
- the number N of stearic acid molecules consumed per nm 2 of silica surface, when stearic acid is reacted with said silica P1 in xylene for 2 hours at 120 ° C is equal to 1, 2.
- the silica P1 is subjected to the deagglomeration test as defined previously in the description.
- This example illustrates the use and the behavior of a silica according to the invention and of a silica not in accordance with the invention in a formulation for industrial rubber.
- the formulations are prepared as follows:
- the discharge of the mixer takes place when the temperature of the chamber reaches 165 ° C (that is to say, approximately thyroid+ 5 min 15 s).
- the mixture is introduced on a roller mixer, maintained at 30 ° C, to be calendered there. On this mixer, CBS, DPG and sulfur are introduced.
- the measurements are carried out on the vulcanized formulations.
- Vulcanization is carried out by bringing the formulations to 150 ° C for 40 minutes.
- the measured value is the abrasion loss: the lower it is, the better the abrasion resistance.
- the silica according to the invention provides mechanical properties at least substantially equivalent, or even better than those obtained with the silica of the prior art.
- the high reinforcing power of the silica according to the invention is confirmed by the high values obtained for the breaking strength and the elongation at break.
- the silica according to the invention exhibits satisfactory behavior in terms of abrasion resistance.
- the measurements are carried out on the vulcanized formulations.
- Vulcanization is obtained by bringing the formulations to 150 ° C for 40 minutes.
- the results (illustrating the warming trend) are reported in Table III below (the lower the value, the less the warming trend). The apparatus used to conduct the measurement was indicated.
- the warming tendency obtained from the silica according to the invention is quite low.
Abstract
Description
Claims
Priority Applications (10)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP96910063A EP0767758B2 (fr) | 1995-03-29 | 1996-03-28 | Nouveau procede de preparation de silice precipitee, nouvelles silices precipitees contenant du zinc et leur utilisation au renforcement des elastomeres |
RU96124773A RU2130425C1 (ru) | 1995-03-29 | 1996-03-28 | Способ получения осажденной двуокиси кремния и осажденная двуокись кремния, полученная этим способом |
US08/737,976 US5958127A (en) | 1995-03-29 | 1996-03-28 | Process for the preparation of precipitated silica, new precipitated silicas containing zinc and their use for the reinforcement of elastomers |
AT96910063T ATE188953T1 (de) | 1995-03-29 | 1996-03-28 | Verfahren zur herstellung von fällungskieselsäure, zinkenthaltenden fällungskieselsäuren und deren verwendung zur verstärkung von elastomeren |
BR9606289A BR9606289A (pt) | 1995-03-29 | 1996-03-28 | Processo de preparação sílica precipitada do tipo compreendendo uma reação do silicato com um agente acidificante e sílica precipitada susceptível de ser obtida segundo este processo |
AU53379/96A AU692700B2 (en) | 1995-03-29 | 1996-03-28 | Novel method for preparing precipitated silica, novel zinc-containing precipitated silicas, and use thereof for reinforcing elastomers |
JP52901296A JP3304095B2 (ja) | 1995-03-29 | 1996-03-28 | 沈降シリカの新規な製造方法、亜鉛を含有する新規な沈降シリカ及びエラストマーを強化するためのそれらの用途 |
KR1019960706795A KR100260328B1 (ko) | 1995-03-29 | 1996-03-28 | 침강 실리카의 새로운 제조 방법, 아연-함유의 새로운 침강 실리카, 및 엘라스토머의 보강에 사용되는 그것의 용도 |
PL96317423A PL183880B1 (pl) | 1995-03-29 | 1996-03-28 | Sposób wytwarzania strącanej krzemionki oraz strącana krzemionka |
DE69606255T DE69606255T3 (de) | 1995-03-29 | 1996-03-28 | Verfahren zur herstellung von fällungskieselsäure, zinkenthaltenden fällungskieselsäuren und deren verwendung zur verstärkung von elastomeren |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR9503676A FR2732330B1 (fr) | 1995-03-29 | 1995-03-29 | Nouveau procede de preparation de silice precipitee, nouvelles silices precipitees contenant du zinc et leur utilisation au renforcement des elastomeres |
FR95/03676 | 1995-03-29 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1996030302A1 true WO1996030302A1 (fr) | 1996-10-03 |
Family
ID=9477537
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/FR1996/000462 WO1996030302A1 (fr) | 1995-03-29 | 1996-03-28 | Nouveau procede de preparation de silice precipitee, nouvelles silices precipitees contenant du zinc et leur utilisation au renforcement des elastomeres |
Country Status (17)
Country | Link |
---|---|
US (2) | US5958127A (fr) |
EP (1) | EP0767758B2 (fr) |
JP (1) | JP3304095B2 (fr) |
CN (1) | CN1079779C (fr) |
AR (1) | AR001455A1 (fr) |
AT (1) | ATE188953T1 (fr) |
AU (1) | AU692700B2 (fr) |
BR (1) | BR9606289A (fr) |
CA (1) | CA2191484A1 (fr) |
DE (1) | DE69606255T3 (fr) |
ES (1) | ES2141488T5 (fr) |
FR (1) | FR2732330B1 (fr) |
PL (1) | PL183880B1 (fr) |
RU (1) | RU2130425C1 (fr) |
TR (1) | TR199600955T1 (fr) |
TW (1) | TW391978B (fr) |
WO (1) | WO1996030302A1 (fr) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
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WO1999036360A1 (fr) * | 1998-01-20 | 1999-07-22 | Rhodia Chimie | Microperles de silice a propriete sensorielle en bouche, leur procede de preparation et compositions dentifrices les contenant |
FR2808266A1 (fr) * | 2000-04-28 | 2001-11-02 | Rhodia Chimie Sa | Granules de silice de precipitation epaississante obtenus par granulation et leur utilisation comme agent epaississant dans les compositions dentaires |
WO2002092508A1 (fr) * | 2001-05-11 | 2002-11-21 | Rhodia Chimie | Granules de silice de precipitation epaississante obtenus par granulation et leur utilisation comme agent epaississant dans les compositions dentaires |
EP1215171A3 (fr) * | 2000-12-14 | 2002-12-11 | Degussa AG | Silice de précipitation dopée |
Families Citing this family (19)
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FR2763581B1 (fr) * | 1997-05-26 | 1999-07-23 | Rhodia Chimie Sa | Silice precipitee utilisable comme charge renforcante pour elastomeres |
FR2818966B1 (fr) * | 2000-12-28 | 2003-03-07 | Rhodia Chimie Sa | Procede de preparation de silice precipitee contenant de l'aluminium |
WO2003002648A1 (fr) * | 2001-06-28 | 2003-01-09 | Societe De Technologie Michelin | Bande de roulement pour pneumatique renforcee d'une silice a basse surface specifique |
CN1325549C (zh) * | 2001-06-28 | 2007-07-11 | 米其林技术公司 | 采用具有非常低比表面积的二氧化硅增强的轮胎胎面 |
DE10146325A1 (de) * | 2001-09-20 | 2003-04-10 | Degussa | Fällungskieselsäure mit hohem BET/CTAB-Verhältnis |
FR2831178B1 (fr) | 2001-10-22 | 2006-04-14 | Rhodia Chimie Sa | Compositions pigmentaires a base de silice |
FR2831179B1 (fr) | 2001-10-22 | 2005-04-15 | Rhodia Chimie Sa | Procede de preparation en milieu aqueux de compositions pigmentaires a base de silice |
FR2833937B1 (fr) * | 2001-12-26 | 2004-11-12 | Rhodia Chimie Sa | Silices a faible reprise en eau |
EP1590297B2 (fr) † | 2003-01-22 | 2016-09-21 | Evonik Degussa GmbH | Silices precipitees de fa on specifique pour des applications dans le domaine du caoutchouc |
DE10353555A1 (de) | 2003-11-14 | 2005-06-30 | Carl Freudenberg Kg | Teilchenverbund, Verfahren zu deren Herstellung und deren Verwendung |
DE102004026685B4 (de) * | 2004-05-28 | 2007-07-12 | Carl Freudenberg Kg | Kautschukzusammensetzungen, Verfahren zur Herstellung von Elastomeren, Elastomere und Verwendung von Verbundteilchen |
US7622097B2 (en) | 2007-07-20 | 2009-11-24 | The National Titanium Bioxide Co., Ltd. (CRISTAL) | Process for hydrothermal production of sodium silicate solutions and precipitated silicas |
US8512664B1 (en) | 2007-07-20 | 2013-08-20 | The National Titanium Dioxide Co. Ltd. (Cristal) | Sodium silicate solutions |
US8734750B2 (en) | 2007-07-20 | 2014-05-27 | The National Titanium Dioxide Co. Ltd. (Cristal) | Sodium silicate solutions |
FR2962996B1 (fr) * | 2010-07-23 | 2012-07-27 | Rhodia Operations | Nouveau procede de preparation de silices precipitees |
RU2540640C1 (ru) * | 2013-07-11 | 2015-02-10 | Федеральное Государственное Бюджетное Образовательное Учреждение Высшего Профессионального Образования "Нижегородский Государственный Университет Им. Н.И. Лобачевского" | Способ получения железоокисных пигментов |
CN103468030B (zh) * | 2013-08-23 | 2016-05-18 | 确成硅化学股份有限公司 | 一种高分散性二氧化硅的制备方法 |
JP6374138B2 (ja) * | 2016-04-28 | 2018-08-15 | 株式会社アドマテックス | 結晶シリカ粒子材料及びその製造方法並びに結晶シリカ粒子材料含有スラリー組成物、結晶シリカ粒子材料含有樹脂組成物 |
CN108383130A (zh) * | 2018-05-04 | 2018-08-10 | 福建远翔新材料股份有限公司 | 一种沉淀水合二氧化硅的合成方法 |
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FR2303763A1 (fr) * | 1975-03-12 | 1976-10-08 | Rhone Poulenc Ind | Nouvelle silice precipitee, procede d'obtention et applications |
US4040858A (en) * | 1974-10-31 | 1977-08-09 | J. M. Huber Corporation | Preparation of precipitated silicas having controlled refractive index |
EP0520862A1 (fr) * | 1991-06-26 | 1992-12-30 | Rhone-Poulenc Chimie | Procédé de préparation de silice précipitée, silices précipitées obtenues et leur utilisation au renforcement des élastomères |
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DE1467012B1 (de) † | 1964-11-26 | 1969-11-06 | Hoesch Chemie Gmbh | Verfahren zur Herstellung eines hochaktiven,im wesentlichen aus Kieselsaeure bestehenden Fuellstoffs |
US4422880A (en) * | 1975-03-12 | 1983-12-27 | J. M. Huber Corporation | Precipitated siliceous products |
FR2632185B1 (fr) * | 1988-06-01 | 1992-05-22 | Rhone Poulenc Chimie | Silice pour compositions dentifrices compatible notamment avec le zinc |
FR2671068B1 (fr) † | 1990-12-28 | 1993-04-23 | Rhone Poulenc Chimie | Nouvelles silices, leur procede de preparation et leur utilisation comme charges notamment pour papiers. |
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1995
- 1995-03-29 FR FR9503676A patent/FR2732330B1/fr not_active Expired - Lifetime
-
1996
- 1996-03-28 AR AR33594896A patent/AR001455A1/es unknown
- 1996-03-28 PL PL96317423A patent/PL183880B1/pl unknown
- 1996-03-28 JP JP52901296A patent/JP3304095B2/ja not_active Expired - Lifetime
- 1996-03-28 CA CA002191484A patent/CA2191484A1/fr not_active Abandoned
- 1996-03-28 CN CN96190423A patent/CN1079779C/zh not_active Expired - Fee Related
- 1996-03-28 TR TR96/00955T patent/TR199600955T1/xx unknown
- 1996-03-28 US US08/737,976 patent/US5958127A/en not_active Expired - Fee Related
- 1996-03-28 TW TW085103759A patent/TW391978B/zh not_active IP Right Cessation
- 1996-03-28 AU AU53379/96A patent/AU692700B2/en not_active Ceased
- 1996-03-28 AT AT96910063T patent/ATE188953T1/de not_active IP Right Cessation
- 1996-03-28 BR BR9606289A patent/BR9606289A/pt not_active IP Right Cessation
- 1996-03-28 EP EP96910063A patent/EP0767758B2/fr not_active Expired - Lifetime
- 1996-03-28 RU RU96124773A patent/RU2130425C1/ru not_active IP Right Cessation
- 1996-03-28 DE DE69606255T patent/DE69606255T3/de not_active Expired - Lifetime
- 1996-03-28 ES ES96910063T patent/ES2141488T5/es not_active Expired - Lifetime
- 1996-03-28 WO PCT/FR1996/000462 patent/WO1996030302A1/fr active IP Right Grant
-
1999
- 1999-02-11 US US09/248,921 patent/US6146454A/en not_active Expired - Fee Related
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US4040858A (en) * | 1974-10-31 | 1977-08-09 | J. M. Huber Corporation | Preparation of precipitated silicas having controlled refractive index |
FR2303763A1 (fr) * | 1975-03-12 | 1976-10-08 | Rhone Poulenc Ind | Nouvelle silice precipitee, procede d'obtention et applications |
EP0520862A1 (fr) * | 1991-06-26 | 1992-12-30 | Rhone-Poulenc Chimie | Procédé de préparation de silice précipitée, silices précipitées obtenues et leur utilisation au renforcement des élastomères |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1999036360A1 (fr) * | 1998-01-20 | 1999-07-22 | Rhodia Chimie | Microperles de silice a propriete sensorielle en bouche, leur procede de preparation et compositions dentifrices les contenant |
FR2808266A1 (fr) * | 2000-04-28 | 2001-11-02 | Rhodia Chimie Sa | Granules de silice de precipitation epaississante obtenus par granulation et leur utilisation comme agent epaississant dans les compositions dentaires |
EP1215171A3 (fr) * | 2000-12-14 | 2002-12-11 | Degussa AG | Silice de précipitation dopée |
US7070749B2 (en) | 2000-12-14 | 2006-07-04 | Degussa Ag | Doped precipitated silica |
WO2002092508A1 (fr) * | 2001-05-11 | 2002-11-21 | Rhodia Chimie | Granules de silice de precipitation epaississante obtenus par granulation et leur utilisation comme agent epaississant dans les compositions dentaires |
Also Published As
Publication number | Publication date |
---|---|
PL183880B1 (pl) | 2002-07-31 |
AU5337996A (en) | 1996-10-16 |
FR2732330B1 (fr) | 1997-06-20 |
US5958127A (en) | 1999-09-28 |
PL317423A1 (en) | 1997-04-14 |
AU692700B2 (en) | 1998-06-11 |
FR2732330A1 (fr) | 1996-10-04 |
ES2141488T5 (es) | 2010-04-15 |
JP3304095B2 (ja) | 2002-07-22 |
AR001455A1 (es) | 1997-10-22 |
CA2191484A1 (fr) | 1996-10-03 |
DE69606255T3 (de) | 2010-07-08 |
DE69606255T2 (de) | 2000-08-10 |
TW391978B (en) | 2000-06-01 |
ES2141488T3 (es) | 2000-03-16 |
CN1152294A (zh) | 1997-06-18 |
TR199600955T1 (tr) | 1997-03-21 |
US6146454A (en) | 2000-11-14 |
CN1079779C (zh) | 2002-02-27 |
EP0767758B2 (fr) | 2009-11-25 |
MX9605925A (es) | 1998-06-30 |
EP0767758A1 (fr) | 1997-04-16 |
EP0767758B1 (fr) | 2000-01-19 |
RU2130425C1 (ru) | 1999-05-20 |
ATE188953T1 (de) | 2000-02-15 |
BR9606289A (pt) | 1997-09-23 |
JPH10504011A (ja) | 1998-04-14 |
DE69606255D1 (de) | 2000-02-24 |
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