DE1264782B - Process for the production of pearl-shaped, water-soluble, high molecular weight polymers - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

C08f

German class: 39 c -25/01

Number: 1264 782 " ^vj: "

File number: M 49957IV d / 39 c

Filing date: August 8, 1961

Opening day: March 28, 1968

Process for the production of pearl-shaped, water-soluble, high molecular weight polymers from water-soluble acrylic monomers by polymerizing a aqueous solution of acrylic monomers in reverse emulsion or suspension in immiscible with water organic liquids in the presence of redox catalysts are already known. The watery one The monomer solution can already contain up to 80 percent by weight of the monomer.

However, according to these known methods, it is not possible to produce uniform high molecular weight products to manufacture.

There has now been a process for the production of pearl-shaped, water-soluble, high molecular weight polymers or copolymers of water-soluble acrylic monomers by polymerization of aqueous Solutions that contain at least one water-soluble acrylic monomer and whose amount of water is smaller than the amount of monomers, as water-in-oil emulsions in water-immiscible organic Liquids found in the presence of catalytic amounts of redox polymerization initiators in which then uniform products that are completely free of insoluble particles can be produced, when the polymerization takes place under reduced pressure.

As water-soluble acrylic monomers, acrylamides, methacrylamides, acrylic acid (including their salts, alkali metal and other water-soluble salts, including acidic addition salts), but also Mixtures of these acrylic monomers used in homo- or copolymerization.

The preparation of the water-soluble acrylic polymers is carried out by polymerizing the monomer while it in the aqueous phase of a water-in-oil emulsion is resolved. The polymers are created in the liquid medium in the form of solid beads. It is without any difficulty possible, polymers with a molecular weight of 500,000 to 5,000,000 or possibly to gain more, determined from the structural viscosity. One can also use polymers with a molecular weight from 15,000,000 to 20,000,000 and above, determined by the method of Light scattering.

The amount of water required to prepare the aqueous monomer solution is less than that Amount of monomers. The ratio of water to monomers is usually about 20 to 30: 100.

The acrylic monomer dissolved in water is dissolved in a mineral oil or other water-immiscible organic liquid, e.g. B. various organic solvents, with process for the production of pearl-shaped,
water-soluble, high molecular weight polymers

Applicant:

Momingstar-Paisley, Inc.,
Hawthorne, NJ (V. St. A.)

Representative:

Dr. F. Zumstein, Dr. E. Assmann,

Dr. R. Koenigsberger

and Dipl.-Phys. R. Holzbauer, patent attorneys,

8000 Munich 2, Bräuhausstr. 4th

Claimed priority:

V. St. v. America 8 August 1960 (47 990)

by means of a suitable emulsifying agent, and if necessary in the presence of a small amount of a suspension stabilizing or agglomeration preventing Means, emulsified.

The amount of water used is in any case smaller than the amount of organic water used Liquid. 1 to 9 parts of water to 10 parts of organic liquid or even less are favorable Amounts of water. Suitable emulsifiers are calcium and zinc oleate, sorbitol sesquioleate and sorbitol monooleate. Practically any emulsifier, especially those soluble in the "oil" phase, can use water-in-oil emulsions brought about, can be used.

The suspension stabilizers or anticaking agents have the practical ones The task of preventing the pearls formed in the course of the polymerization from sticking together. In In some cases the presence of a filler as a supplement is very desirable. Will be the filler used together with the appropriately concentrated surface-active emulsifier, so is its function as a dispersant is enhanced. Mineral fillers represent a very practical type of Agglomeration inhibitors and include compounds such as tricalcium phosphate, hydroxyapatite or silicates. Other useful compounds are sparingly soluble salts such as calcium and magnet sium carbonate, calcium and magnesium silicates and finely divided oxides such as clay, fuller's earth, talc

809 520/683

3 4

and bentonite. Organic substances that are the same The respective grain size of the according to the process Fulfill purpose, such as starch, gelatin, cellulose derivatives of the invention produced beads is based on the following or polyvinyl alcohol, can also use requirements:

find The stabilizers and the inhibitors _{L Fnste distribution of the} water-oil emulsion,

_{against agglomeration,} for example, calcium 5 _2> stirring speed during polymerization,

phat, can the reaction medium before entering the 3 ^ _rt ^ ₅ agitator

Reaction or polymerization in the sticky ₄ ] _{M and size of the mineral} feet. Phase can be added at any point in time. It is most advantageous to add this at the beginning of the process. In general, the amount of mine added or to introduce it into the water-organic-liquid fillers between 0.1 and 5.0% and keits mixture before homogenization. above (based on the entire suspension).

In certain cases one can use the procedure. -T ₁

also change by moving into the water phase B e 1 s ρ 1 e J

the emulsion starch, gum or other water-soluble emulsion made from the following ingredients

brings in borrowed funds. You can also use 15 750 _{cc of} toluene

Addition of oil-soluble or swellable thickening _{7 5} tricalcium phosphate

average the susceptibility to suspension of the 25V sorbitol sesquioleate during production

mineral oils used in the emulsion or other ^ _n * woo * »- ''

1 T-, _t ·· · 1 ·, t ··! "^ Ö YYdboGl,

organic liquids increase. ·

190 g of acrylamide and 10 g of acrylic acid are added to the water-immiscible organic liquid

speed is an inert, hydrophobic liquid and represents sets. The reaction vessel was filled with nitrogen

the "oil represents" the water-in-oil emulsion. In purified water and heated to 3O ⁰ C. The reaction vessel

immiscible organic liquids, which are kept at negative pressure, the reaction by means of

can be used, heptane, toluene 2 ecm of the redox catalyst described are also in operation

and carbon tetrachloride. 25 brought and the reaction continued for so long

The acrylic monomer emulsion will continue until pearls form.

known manner prepared by first the redox catalyst was made by mixing

Water emulsified in the organic liquid and 63.2 g of ceric ammonium sulfate in 1000 parts of water

then the monomer is added, or vice versa, by adding 50 ecm of concentrated sulfuric acid and

you first dissolve the monomer in water and then dissolve anhydrous sodium sulfite in water

then the solution obtained is prepared in the organic liquid - a 2 ¹ Io ⁰ I ₀ IgQn solution,

emulsified. In both cases, the emulsifying agent can be used.

process by homogenizing in a colloid mill Example _

are promoted and thus a particularly fine mixture of the following components

division of the water or the aqueous solution in the 35-750 _{ccm of} toluene

organic hydrophobic liquid can be achieved. ₇₅ T _rica i _c i _um phosphate,

Em redox catalyst, which is particularly suitable 25 g sorbitol sesquioleate,

for making pearls with an optimal ^ q ^ water

high molecular weight, has the following compounds- 7 hydrochloric acid

Settlement: ceric ammonium sulphate together with water- ₄ or ₁₀ ~ dimethylaminoethyl methacrylate,
free sodium sulfate in aqueous acidic solution. It

You can also use other redox catalysts, such as 190 g of acrylamide. The reaction

Vascular sodium salt of Na or Formaldehydsulfoxylats is purged with nitrogen and at 30 ⁰ C

trium bisulfite as a reducing agent, and hydrogen-heated. The vessel is kept under negative pressure »

peroxide or ammonium or potassium persulphate or the reaction using that mentioned in Example 1

Sodium chlorate can be used as an oxidizing agent. Redox catalyst started up and the reac-

After adding a redox catalyst, the ion is continued until pearls are formed. Emulsion is heated to get the polymerization going

bring. Due to the exothermic example 3

However, heat will continue the reaction as long as 50

until the polymer formed, after only 6 g of glycerine monostearate (with an »HLB-Vert«

had become sticky-soft, formed into hard pearls. of 11.0) are dissolved in 700 ccm of toluene ^{at 40 3 C}

It may be necessary to dissolve the reaction (Part I). 200 g of acrylamide are through

To cool the mass, so that the reaction temperature de- Heat dissolved in 60 ccm of distilled water

remains speaking low to an evaporation of 55 (Part II). Part II is slowly added to Part I and

too much water and also to avoid imidization. by homogenizing in an Eppenbach homo-

The reaction is carried out under reduced pressure. The generator formed an emulsion. The

offers the advantage that the non-aqueous medium temperature maintained at 35 to 40 ⁰ C. The emulsion

volatilized and so the reaction medium is placed in a three-neck bottle, which is cheaper with

Reaction temperature is maintained. 60 is provided with a reflux condenser. It is nitrogen

The pearls obtained can easily be passed through the emulsion by gas for purification

Centrifuge the organic liquid and keep the temperature at 3O ⁰ C. The Reini-

separated from the remaining water. This takes a few minutes and takes place with stirring

As can be seen from the examples, are Suspen- (200 rev / min.).

sion stabilizer or agglomeration inhibitor 65 The tap with the nitrogen is closed,

gates not absolutely necessary, in contrast to the the bottle is pumped out and a vacuum of

lipophilic, surface-active emulsifiers, 180 mm Hg for the entire duration of the reaction.

which are necessary to obtain an emulsion. ' posed.

The redox catalyst is the same as in example 1.

The addition of 2-4 cc of redox catalyst brings the reaction started, during which the temperature does not rise above 63 ⁰ C, as cold, condensed flow back toluene and permanently cold water flows through the outer jacket of the reaction bottle.

After the reaction has ended, the toluene is centrifuged off and drawn off. The polyacrylamide beads are dried in an oven. They are clearly soluble in water, and the molecular weight is 20,000,000.

Comparative example

Repetition of example 3 at atmospheric pressure.

6 g of glycerol monostearate are dissolved in 700 ecm of toluene at 40 ° C. (part I).

200 g of acrylamide are dissolved in 60 ecm of distilled water with heating (part II).

Part II is slowly added to part I and is formed by homogenization in an Eppenbach homogenizer, an emulsion, during which the temperature is maintained at 35 to 4O ⁰ C. The emulsion is placed in a three-neck bottle fitted with a reflux condenser. It is purified by passing through the emulsion nitrogen gas, the temperature being maintained at 3O ⁰ C. The cleaning takes a few minutes and takes place with stirring {200 rev / min.).

There is no vacuum applied, but working under atmospheric pressure.

The addition of 2 to 4 ecm redox catalyst sets the polymerization in motion. The temperature rises to 93 ^° C., since cold condensed toluene flows back and cold water flows continuously through the outer jacket of the reaction bottle. After the reaction has ended, the toluene is centrifuged off and the product is dried.

If the final product is resolved as a l ° / _o aqueous solution, it is insoluble particles. The presence of these insoluble particles is evidence that when a vacuum is not used, crosslinking and gelation have occurred and, in this case, a non-uniform polymerization product is obtained.

The methods given in the preceding examples can be varied by adding others Ingredients used and water in a different percentage ratio, e.g. B. the water in abundance from 20 to 40 parts based on mineral oil or other organic liquid. Numerous combinations the reducing and oxidizing agents were combined with the catalysts mentioned. Solid polyacrylamide beads were always obtained in such reactions. The molecular weight can not only be done in the usual way by the type of redox catalysts used in each case set, but can also be controlled by the amount of catalyst. The course of the reaction can be achieved by increasing the hydrogen ions, ζ. Β. by adding sulfuric acid, accelerated will. Furthermore, the molecular weight can be determined in a known manner with the aid of mercaptans Regulation of the temperature and by adding metal salts such as iron, chromium and nickel salts, regulate.

The water-soluble polymers prepared according to the invention find z. B. in mining, in paper production, in the treatment of water, as a textile auxiliary and as a means for improving the Soil use.

In the field of mining, the polymers produced according to the invention act as flocculants, by removing clay and similar substances from suspensions, with supernatant liquors that can be easily processed. The same thing happens with the treatment of water, wherein the clear liquid can be recycled or drained without the problem of contamination arising from suspended solids arises. In papermaking The acrylic polymers serve to bind the titanium oxide to the paper product. The evenness play here and the extraordinarily high molecular weight of the products made according to the invention a significant role. The products are used in the field of textile production as a thickener for printing pastes or as a soluble sizing agent for hydrophobic fibers.

Claims (1)

Claim: Process for the production of pearl-shaped, water-soluble, high molecular weight polymers or copolymers of water-soluble acrylic monomers by polymerization of aqueous Solutions containing at least one water-soluble acrylic monomer and their amount of water is less than the amount of monomers than water-in-oil emulsions in with water miscible organic liquids in the presence of catalytic amounts of redox polymerization initiators, characterized in that the polymerization takes place under reduced pressure. Considered publications:
German Auslegeschriften No. 1,081 228,1082 409; laid out documents of Belgian patent No. 585 256. 809 520/683 3.68 © Bundesdruckerei Berlin