EP0162716A2
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EP
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A process for preparing polymer particles
Assignee: GEA Process Engineering AS
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Filing: 1985-05-22
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Granted: —
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Expires: 2005-05-22
Abstract
Abstract Substantially spherical solid particles of a substantially uniform particle size are prepared by dispersing a solution of a polymerizable substance in a first liquid by means of a suitable emulsifier to form droplets of the polymerizable substance of a substantially uniform particle size, which are thereafter poured into a second liquid with which the first liquid is immiscible and which contains a sufficient amount of a reactant to polymerize the polymerizable substance. After the polymerization the substantially embodiment, an aqueous solution of an alkaline metal silicate, especially sodium silicate, is dispersed in a coparaffinate by means of a suitable emulsifier, and the emulsion is poured into an aqueous solution of the polymerization reactant to form gelled, substantially spherical hydrated silica particles.
Inventors
- 👤 Ove Emil Hansen
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 05:08
CPC Classifications
C; C01; C01G; C01G25/00; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/14; C01B33/152; C01B33/16; C01B33/166; C01F; C01F7/00; C01F7/02; C01G25/02; C12; C12N; C12N11/00; C12N11/14; C01P; C01P2004/00; C01P2004/30; C01P2004/32; C01P2004/51; C01P2004/52
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
88 words
A process for preparing substantially spherical solid particles of a substantially uniform particle size, said method comprising dispersing a solution of a polymerizable substance in a first liquid by meant of a suitable emulsifier to form droplets of the polymerizable substance of a substantially uniform particle size, pouring the emulsion Into a second liquid with which the first liquid is immiscible and which contains a sufficient amount of a reactant to polymerize the polymerizable substance, and recovering the polymerized, substantially spherical particles of the polymerizable substance thus formed.
Claim 2
Dependent Claim
88 words
A process for preparing substantially spherical solid particles of a substantially uniform particle size, said method comprising dispersing a solution of a polymerizable substance in a first liquid by meant of a suitable emulsifier to form droplets of the polymerizable substance of a substantially uniform particle size, pouring the emulsion Into a second liquid with which the first liquid is immiscible and which contains a sufficient amount of a reactant to polymerize the polymerizable substance, and recovering the polymerized, substantially spherical particles of the polymerizable substance thus formed.
Claim 3
Dependent Claim
16 words
A process according to claim 1, In which the polymerizable substance is an inorganic gel-forming compound.
Claim 4
Dependent Claim
15 words
A process according to claim 1, in which the emulsion is a water-in-oil type emulsion.
Claim 5
Dependent Claim
37 words
A process according to claim 2, in which the inorganic gel-forming compound is selected from the group consisting of silica sol and alkali metal silicates, aluminates and zirconates, preferably an alkali metal silicate such as sodium silicate.
Claim 6
Dependent Claim
27 words
A process according to claim 1, in which the first liquid Is an organic liquid the density of which differs significantly from that of the second liquid.
Claim 7
Dependent Claim
17 words
A process according to claim 5, In which the organic liquid is a hydrocarbon, preferably a coparaffinate.
Claim 8
Dependent Claim
25 words
A process according to claim 1, in which the second liquid is miscible with the liquid in which the polymerizable substance is dissolved, preferably water.
Claim 9
Dependent Claim
18 words
A process according to claim 1, In which the polymerization reactant is an acid or an acid buffer.
Claim 10
Dependent Claim
24 words
A process according to claim 1, In which the average particle size of the polymerized particles is In the range of about 1-100 m.
Claim 11
Dependent Claim
52 words
A process according to claim 1, in which an aqueous solution of an alkali metal silicate such as sodium silicate is dispersed in a cops- raffinate by means of the emulsifier, the emulsion formed being poured into an aqueous solution of the polymerization reactant to form gelled, substantially spherical hydrated silica particles.
Claim 12
Dependent Claim
28 words
A process according to claim 10, in which the aqueous solution of the alkali metal silicate is an aqueous solution of sodium silicate in a concentration of 8-20%.
Claim 13
Dependent Claim
27 words
A process according to claim 10, in which the sodium silicate is sodium sillicate of the formula Na 2 O(SiO 2 ) x' wherein x is 3-4.
Claim 14
Dependent Claim
57 words
A process according to claim 10, in which the second liquid is an aqueous buffer of a pH In the range of 4-7 such as an acetate buffer, which is present in a volume sufficient to maintain a final pH in the mixture of the emulsion and the second liquid of below 7, such as about 5.3.
Claim 15
Dependent Claim
31 words
A process according to claim 10, in which the polymerized, substantially spherical hydrated silica particles are subjected to an acid treatment by boiling In a mineral acid such as hydrochloric acid.
Claim 16
Dependent Claim
75 words
A process according to claim 1, in which the solution of the polymerizable substance is dispersed In the first liquid by simultaneously and continuously feeding the solution of the polymerizable substance and the first liquid, which contains the emulsifier, into a substantially cylindrical, elongated passage defined in a body member at such a flow rate that the passage is only partly filled up by the liquids to be emulsified, and by vibrating the body member.
Claim 17
Dependent Claim
30 words
A process according to claim 1, in which the solution of the polymerizable substance and the first liquid, which contains the emulsifier, is simultaneously driven through at least one orifice.
References Cited (Backward Citations)
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