Silica suspension in an organic solvent and method for its manufacture

Patent metadata

Field	Value
Publication number	US-12344727-B2
Application number	US-201916965987-A
Country	US
Kind code	B2
Filing date	Jan 30, 2019
Priority date	Feb 1, 2018
Publication date	Jul 1, 2025
Grant date	Jul 1, 2025

Abstract

Suspensions of silica particles in organic liquids are disclosed as well as a method for their preparation.

First claim

The invention claimed is:

1. A suspension of silica particles comprising:
a liquid [liquid (L)] selected from the group consisting of the linear or branched, saturated or unsaturated, aliphatic and cycloaliphatic hydrocarbons having from 6 to 30 carbon atoms and of the aromatic hydrocarbons having from 6 to 10 carbon atoms,
silica particles, wherein the silica particles are precipitated silica particles, and
at least one compound [compound (S)] selected from the group consisting of:
the acid phosphate esters of formula (I)
P(O)((OCH 2 CH 2 ) n OR) a (OM) b   (I)

wherein:
R represents a linear or branched, saturated or unsaturated, aliphatic hydrocarbon group having from 1 to 24 carbon atoms or an aromatic hydrocarbon having from 6 to 24 carbon atoms; M is H, Na or K, n is an integer from 4 to 8;
a is an integer equal to 1 or 2, and b is 3-a;

characterised in that said compound(S) is miscible in liquid (L) in the temperature range from 20° C. to 50° C.

2. The suspension according to claim 1 wherein the silica particles are characterized with a particle size of less than 600 nm as measured by dynamic light scattering.

3. The suspension according to claim 1 wherein the silica particles are present in an amount of from 1 to 60% by weight with respect to the total weight of the suspension.

4. The suspension according to claim 1 wherein liquid (L), is selected from the group consisting of n-hexane, n-heptane, n-octane, n-nonane, n-decane, n-dodecane, n-hexadecane, and cyclohexane.

5. The suspension according to claim 1 wherein compound(S) is present in an amount of from 5 to 50% by weight with respect to the dry weight of the silica particles.

6. The suspension according to claim 1 wherein compound(S) is such that the viscosity, measured at room temperature, of suspensions comprising n-hexadecane, silica particles in an amount of 20% by weight with respect to the total weight of the suspension, and compound(S) in a compound(S) to silica ratio in the range from 30 to 60% by weight is less than 100 mPa·s.

7. The suspension according to claim 1 wherein compound(S) is such that the viscosity, measured at room temperature, of suspensions comprising o-xylene, silica particles in an amount of 20% by weight with respect to the total weight of the suspension, and compound(S) in a compound(S) to silica ratio in the range from 30 to 60% by weight is less than 50 mPa·s.

8. A process for the preparation of the suspension of claim 1 comprising milling the precipitated silica in the presence of liquid (L) and of at least one compound(S) in a wet milling apparatus.

9. The process of claim 8 which comprises the following steps:
i. providing a solution of at least one compound (S) in liquid (L),
ii. adding the precipitated silica; and
iii. milling in a wet milling apparatus.

10. A composition comprising the suspension of claim 1 and at least one polymer.

11. A method for the preparation of the composition of claim 10 comprising mixing the suspension of claim 1 with a solution or suspension of the polymer in an organic liquid.

12. A composition comprising the suspension of claim 1 and at least one polymerizable monomer.

Assignees

• Rhodia Operations

Inventors

• Chaussee Thomas
• Magnin-Feysot Frédéric
• Fay Hélène
• Baussaron Loïc
• Le Thiesse Jean-Claude

Classifications

• C09C1/3018

  Grinding · CPC title

• C08K2201/005

  Additives being defined by their particle size in general · CPC title

• C08J3/215

  at least one additive being also premixed with a liquid phase · CPC title

• C01P2006/22

  Rheological behaviour as dispersion, e.g. viscosity, sedimentation stability · CPC title

• C01P2004/62

  Submicrometer sized, i.e. from 0.1-1 micrometer · CPC title