SU138050A1 - The method of obtaining aqueous dispersions of synthetic materials - Google Patents

Description

Currently used as sizing compositions for manufacturing paper, cardboard, dry plaster, and others. Rosin, paraffin and other similar emulsions do not provide a sufficiently strong and waterproof material. At the same time, the use of synthetic resins and latexes for this purpose (urea or melamine-formaldehyde resins, silicone latexes, etc.) is limited by the need to apply high temperatures and pressures; In addition, synthetic resins tend to increase the rigidity and brittleness of cellulosic materials.

A new method has been developed for obtaining aqueous dispersions free of the above disadvantages from synthetic materials, namely, in order to obtain stable, weather-resistant emulsions suitable as impregnating and sizing compositions, a composition consisting of unsaturated polyesters, a monomer and a polymerization initiator is used. the latter, for example polyether acrylates, styrene and benzoyl peroxide.

Example. For the preparation of the emulsion of the above composition is used (in%);

1) 1% solution breech in water40

2) a mixture of polyether acrylates with monomer and initiator. . 60 The composition of a mixture of polyetheracryl includes (in%):

a) dimethacrylate-bis-triethylene glycol phthalate

(polyester MGF-9) 70

b) tetramethacrylate-bis-glycerin phthalate (polyether TMGF-11) 20

c) styrene9

d) initiator benzoyl peroxide 1

To a metered amount of a one percent aqueous casein solution with vigorous stirring (the speed of rotation of the bashalka is 2000

 138050-2 -

2500 rpm slowly with a speed of 7-10 ml / min poured a mixture of polyesters with monomer and initiator. Upon completion of the addition of the mixture, the resulting emulsion is stirred for another 10-15 minutes.

At room temperature, the prepared emulsion remains stable for more than 15 days and can be diluted with water in any ratio.

In order to check the quality of the resulting emulsion, three batches of paperboard paper are made according to the known technology using as a binder: rosin glue, SBT grade resin and the described polyester acrylate emulsion. The corresponding cardboard samples are immersed in water for 24 hours. After such a test, the water absorption was for sizing cardboard (%):

rosin glue10

emulsion resin SBT13

emulsion polyester acrylates 5

These indicators confirm the advantage of the proposed emulsions over the previously known.

Subject invention

A method of producing aqueous dispersions of synthetic materials, characterized in that, in order to expand the raw material base and to obtain stable, atmospheric emulsions suitable as impregnating and sizing compositions, a composition consisting of unsaturated polyesters and monomer is used, for example polyester acrylates and styrene .