Polymer dispersions for fire prevention and firefighting
AssigneeEvonik Degussa GmbH
InventorsBernd Diener, Veronika Gehler, Erich Kuester, Daniel Roulands, Dieter Wehrhahn
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Abstract
The present invention relates to water-in-oil polymer dispersions comprising of a continuous organic phase and therein finely dispersed and cross-linked, water-swellable polymerizates, where these have a residual monomer content of less than 1,000 ppm. The present invention relates further to a process for the production of polymer dispersions according to the invention. In addition, the present invention relates to devices for fire prevention and firefighting and to the use of the polymer dispersions according to the invention.
Claims16
A process for preventing fires or fighting fires, the process comprising:
- providing a fire extinguishing agent;
- wherein the agent is made according to the process comprising treating water with an amount of a water-in-oil polymer dispersion sufficient to produce an agent having a viscosity of 100 mPas or more, wherein the water-in-oil dispersion comprises:
- (i) a continuous organic phase immiscible with water;
- wherein said continuous organic phase comprises:
- (A) a fatty acid ester or mixture of at least two fatty acid esters;
- and
- (B) white oils from petroleum distillation or ligroin;
- wherein said white oils have a boiling range of 150° C. to 200° C.;
- and
- (ii) finely dispersed and cross-linked, water-swellable polymerizates;
- wherein said polymerizates were produced via an inverse phase polymerization process;
- and
- wherein an amount of a residual monomer present in the water-in-oil dispersion is less than 1,000 ppm after a predetermined amount of a residual monomer eliminator is provided to the water-in-oil dispersion;
- and
- wherein the water-in-oil dispersion has an environmental compatibility measured by having an EC50 value over about 10 mg/l according to OECD Guideline 201 and OECD Guideline 202;
- and
- applying the agent to a surface.
A method for using an agent for fire protection and/or fire fighting, the method comprising:
- (a) providing an agent comprising a water-in-oil polymer dispersion mixture comprising:
- (i) a continuous organic phase immiscible with water;
- wherein said continuous organic phase comprises
- (A) a fatty acid ester or mixture of at least two fatty acid esters;
- and
- (B) white oils from petroleum distillation or ligroin;
- wherein said white oils have a boiling range of 150° C. to 200° C.;
- (ii) finely dispersed and cross-linked, water-swellable polymerizates;
- and
- (iii) a residual monomer content of less than 1,000 ppm;
- wherein after the inverse phase polymerization of an emulsion to produce the cross-linked, water-swellable polymerizates, a sufficient amount of a residual monomer eliminator selected from the group consisting of:
- (A) acid or neutral salts derived from sulfur with an oxidation number less than VI;
- (B) sodium dithionite;
- (C) sodium thiosulfate;
- (D) sodium sulfite or sodium disulfite;
- (E) substances with a hydrogen sulfide group;
- (F) sodium hydrogen sulfide;
- or
- (G) compounds from the groups of:
- (1) thiols,
- (2) mercaptoethanol,
- (3) dodecylmercaptan,
- (4) thiopropionic acid,
- (5) salts of thiopropionic acid,
- (6) salts of thiopropane sulfonic acid, or
- (7) salts of amines
- is communicated with the resulting water-in-oil polymer dispersion to reduce the residual monomer content to less than about 1,000 ppm;
- (b) treating water with an amount of the agent sufficient to raise the viscosity of the resulting mixture to 100 mPas or more to produce a fire extinguishing agent having an environmental compatibility measured by having an EC50 value over about 10 mg/l according to OECD Guideline 201 and OECD Guideline 202;
- and
- (c) applying said fire extinguishing agent to a surface.
Dependencies are inferred from the claim text.