Method of making a multi-phase aggregate using a multi-stage process
AssigneeCabot Corporation
InventorsKhaled Mahmud, Meng-Jiao Wang
Life of this patent
Estimating the term…
Abstract
Elastomeric compositions are described and include at least one elastomer and an aggregate having a carbon phase and a silicon-containing species phase. The aggregate exhibits one or more specific characteristics. Methods of improving the rolling resistance of an elastomeric composition are also described and include introducing the aggregate into an elastomeric composition.
Claims18
An elastomeric composition comprising at least one elastomer, an aggregate, and optionally a coupling agent, said aggregate comprising a carbon phase and a silicon-containing species phase, wherein said aggregate has at least one of the following characteristics:
- a) a difference between BET (N2) surface area and external surface area of from about 2 to about 100 m2/g;
- b) a difference between BET (N2) surface area and external surface area of from about 1 to about 50 m2/g after hydrofluoric acid treatment;
- c) a ratio of from about 0.1 to about 10 based on 1) the m2/g difference in BET (N2) surface area between the aggregate after and before hydrofluoric acid treatment to 2) weight percentages of elemental silicon content in said aggregate without hydrofluoric acid treatment;
- d) a weight average aggregate size measured by Disc centrifuge photosedimentameter after hydrofluoric acid treatment is reduced by about 5% to about 40% compared to weight average aggregate size without hydrofluoric acid treatment;
- e) a silica ash content in said aggregate of from about 0.05% to about 1% based on the weight of said aggregate after hydrofluoric acid treatment and based on ash resulting from silicon-containing compound;
- and
- f) a BET surface area of silica ash in said aggregate of from about 200 m2/g to about 700 m2/g.
A method of improving the rolling resistance in an elastomeric composition comprising introducing an aggregate into the elastomeric composition, wherein said aggregate comprises a carbon phase and a silicon-containing species phase, wherein said aggregate has at least one of the following characteristics:
- a) a difference between BET (N2) surface area and external surface area of from about 2 to about 100 m2/g;
- b) a difference between BET (N2) surface area and external surface area of from about 1 to about 50 m2/g after hydrofluoric acid treatment;
- c) a ratio of from about 0.1 to about 10 based on 1) the m2/ g difference in BET (N2) surface area between the aggregate after and before hydrofluoric acid treatment to 2) weight percentages of elemental silicon content in said aggregate without hydrofluoric acid treatment;
- d) a weight average aggregate size measured by Disc centrifuge photosedimentameter after hydrofluoric acid treatment is reduced by about 5% to about 40% compared to weight average aggregate size without hydrofluoric acid treatment;
- e) a silica ash content in said aggregate of from about 0.05% to about 1% based on the weight of said aggregate after hydrofluoric acid treatment and based on ash resulting from silicon-containing compound;
- and
- f) a BET surface area of silica ash in said aggregate of from about 200 m2/g to about 700 m2/g.
Dependencies are inferred from the claim text.