Abstract: A chemically modified precipitated silica characterised by the presence of alkyl moieties chemically bound to the silica and a process for its manufacture.

Abstract: A precipitated silica having a broad particle size distribution and large median particle size as well as its method of manufacture is provided. The precipitated silica has a CTAB surface area SCTAB in the range from 40 to 300 m2/g, a difference between BET surface area SBET and CTAB surface area SCTAB of at least 35 m2/g, a width of the particle size distribution Ld, measured by centrifugal sedimentation, of at least 1.5, an amount of aluminium WA1 in the range from 0.5 to 7.0 wt %, and a median particle size d50, measured by centrifugal sedimentation, such that for a given value of CTAB surface area SCTAB and amount of aluminium WAl, parameter A, defined by the following equation: A=|d50|+0.782×|SCTAB|?8.524×|WAl|.

Abstract: A precipitated silica suitable for thermal insulation applications and a process for its manufacture.

Abstract: A precipitated silica characterised by the presence of specific acid sites on its surface and a process for its manufacture.

Abstract: Precipitated silica having large median particle size for use as reinforcing filler in elastomeric compositions as well as its method of manufacture. In particular, a precipitated silica characterised by a CTAB surface area SCTAB in the range from 70 to 350 m2/g; an amount WM of at least one metal M selected from elements of groups 3, 4 and 5 of at least 0.1 mol %; and a median particle size d50, measured by centrifugal sedimentation, such that: |d50|?183×|RION|×|WM|?0.67×|SCTAB|+233 (I) wherein |d50| represents the numerical value of median particle size d50 measured by centrifugal sedimentation and expressed in nm; |RION|, the numerical value of the ionic radius of metal M expressed in nm; |SCTAB|, the numerical value of the CTAB surface area SCTAB expressed in m2/g; and |WM|, the numerical value of the percentage molar amount of the metal WM.

Abstract: A rubber composition is based on at least one elastomer, a reinforcing inorganic filler, an agent for coupling the elastomer to the reinforcing inorganic filler, and a crosslinking system. The reinforcing inorganic filler comprises at least one silica S having: a CTAB specific surface area SCTAB within a range extending from 40 to 300 m2/g; a difference between the BET specific surface area SBET and the CTAB specific surface area SCTAB of greater than or equal to 35 m2/g; an aluminium content WAl within a range extending from 0.5 to 7.0% by weight relative to the weight of the silica S; a width of the aggregate size distribution Ld, measured by centrifugal sedimentation, of greater than or equal to 1.5; and a median aggregate diameter d50, measured by centrifugal sedimentation, such that for a given value of CTAB specific surface area SCTAB and a given aluminium content WAl, a magnitude A is defined by the following equation (I): A=[d50]+0.782×[SCTAB]?8.

Abstract: A precipitated silica characterised by the presence of specific acid sites on its surface and a process for its manufacture.

Abstract: A precipitated silica suitable for thermal insulation applications and a process for its manufacture.

Abstract: A chemically modified precipitated silica characterised by the presence of alkyl moieties chemically bound to the silica and a process for its manufacture.

Abstract: A precipitated silica characterised by the presence of specific acid sites on its surface and a process for its manufacture.

Abstract: A rubber composition is based on at least one elastomer, a reinforcing inorganic filler, an agent for coupling the elastomer to the reinforcing inorganic filler, and a crosslinking system. The reinforcing inorganic filler comprises at least one silica S having: a CTAB specific surface area SCTAB within a range extending from 40 to 300 m2/g; a difference between the BET specific surface area SBET and the CTAB specific surface area SCTAB of greater than or equal to 35 m2/g; an aluminium content WAl within a range extending from 0.5 to 7.0% by weight relative to the weight of the silica S; a width of the aggregate size distribution Ld, measured by centrifugal sedimentation, of greater than or equal to 1.5; and a median aggregate diameter d50, measured by centrifugal sedimentation, such that for a given value of CTAB specific surface area SCTAB and a given aluminium content WAl, a magnitude A is defined by the following equation (I): A=[d50]+0.782×[SCTAB]?8.

Abstract: A precipitated silica characterised by the presence of specific acid sites on its surface and a process for its manufacture.

Abstract: Precipitated silica having a broad particle size distribution and large median particle size as well as its method of manufacture.

Abstract: A process for preparing precipitated silica in which: (i) an aqueous stock having a concentration of alkali metal silicate less than 20 g/L is formed; (ii) acid is added to said initial stock, until at least 50% of the amount of M2O is neutralized; (iii) silicate and acid are simultaneously added, such that the degree of consolidation is greater than 4 and at most 100; (iv) silicate and acid are simultaneously added, such that the pH of the reaction medium is between 7 and 10; (v) acid is added until a pH value of between 2.5 and 5.3 is obtained; and (vi) the reaction medium is placed in contact with acid and silicate, such that the pH is between 2.5 and 5.3, wherein the acid used in at least one of the process steps is a concentrated acid.

Abstract: A process for preparing precipitated silica in which: (i) an stock having a concentration of alkali metal M silicate less than 20 g/L is formed; (ii) acid is added to said initial stock, until at least 50% of the amount of M2O is neutralized; (iii) silicate and acid are simultaneously added, such that the degree of consolidation is greater than 4 and at most 100; and (v) acid is added until a pH value of between 2.5 and 5.3 is obtained, wherein the acid used in at least one of the process steps is a concentrated acid.

Abstract: The invention concerns the combined use, in an elastomer composition preferably comprising an isoprene elastomer, a precipitated silica containing titanium and a specific conjugated diene compound, such as a conjugated diene phosphonate or phosphinate compound. It also concerns the elastomer compositions obtained and the items produced from said compositions.

Abstract: A process for preparing precipitated silicas in which: (i) an aqueous stock with a pH of between 2 and 5 is formed; (ii) silicate and acid are simultaneously added to said stock, such that the pH of the resulting reaction medium is maintained between 2 and 5; (iii) silicate is added until a pH value of between 7 and 10 is obtained; (iv) silicate and acid are simultaneously added, such that the pH of the reaction medium is between 7 and 10; (v) acid is added until a pH value of between 2.5 and 5.3 is obtained; and (vi) the reaction medium is placed in contact with acid and silicate, such that the pH is between 2.5 and 5.3; wherein the acid used in at least one of the process steps is a concentrated acid.

Abstract: The invention relates to a process for the preparation of precipitated silica formed of aggregates of large primary silica particles, at the surface of which occur small primary silica particles, in which the acid used in at least one of the process steps is a concentrated acid.

Abstract: The invention relates to a method for preparing precipitated silica, consisting in: (i) forming a starter having a pH of between 2 and 5; (ii) simultaneously adding silicate and acid, such that the pH of the reaction medium is between 2 and 5; (iii) adding silicate until the pH is between 7 and 10; (iv) simultaneously adding silicate and acid, such that the pH is between 7 and 10; (v) adding acid until the pH is between 2.5 and 5.3; (vi) bringing the reaction medium into contact with the acid and the silicate, such that the pH is between 2.5 and 5.3; and (vii) adding silicate, such as to increase the pH to a value between 4.7 and 6.3.

Abstract: Precipitated silicas including clusters of large primary silica particles having at the surface thereof small primary silica particles, have a specific surface area CTAB (SCTAB) ranging from 60 to 400 m2/g; a cluster average size d50, as measured by XDC grading after ultrasound deagglomeration, such that d50 (nm)>(6214/SCTAB (m2/g)+23; a pore volume distribution such that V(d5-d50)/V(d5-d100)>0.906?(0.0013×SCATB (m2/g)); and a pore size distribution such that Mode (nm)>(4166/SCTAB (m2/g))?9.2; such silicas are useful reinforcing fillers for polymers.