CS214685B2 - Process for preparing homopolymers and copolymers of unsaturated ureas - Google Patents

Abstract

The invention relates to a method for producing new homopolymers and copolymers of acryloyl- or methacryloyl ureas. The monomer substances are new. The polymerization is carried out in a known manner. All water-soluble olefinically unsaturated compounds are suitable as comonomers, in particular monomers of the acrylic and methacrylic series and also vinyl esters. The polymers can be used as flocculating, sedimentation, dewatering and retention agents.

Description

The invention relates to a process for producing homopolymers and copolymers of novel acryloyl methacryloyl ureas.

Virtually all cationic polymers of the type mentioned that are produced derive their cationic character from quaternary ammonium groups [for a literature review, see

M. F. Hoover, J. Macromol. Sci. Chem. A 4 (6) (1970), pp. 1327-1418].

The subject of the invention is a method for producing homopolymers and copolymers containing repeating structural units of the general formula

X i

-CH.-CH ^Z I .

WHAT

where

X represents either hydrogen or methyl,

R represents an alkyl group with 1 to 4 carbon atoms, m represents the number 0 or 1, n represents an integer from 1 to 4 and Z represents any salt-forming anion, such as chloride, bromide, iodide, sulfate, perchlorate, nitrate or acetate, the corresponding copolymers containing 4 to 96% by weight of the said repeating units and the remainder consisting of repeating units derived from at least one vinyl monomer which is copolymerizable with the said compounds, characterized in that the unsaturated starting compound of the general formula I

OX hn-'cc-ch =ch ₂

I °=C /0 \ (í) where

X, R, m, n and Z have the meanings given above, or a mixture thereof with other polymerizable monomers undergoes polymerization.

Suitable comonomers include all water-soluble olefinically unsaturated compounds, for example acrylic and methacrylamide and their N-substituted derivatives, in particular N-[3-dimethylaminopropyl]acrylamide and its salts and quaternary compounds, N-methylolacrylamide and -methacrylamide and their ethers, amino-substituted ethers of acrylic and methacrylic acid, such as diethylaminoethyl acrylate and dimethylaminoethyl methacrylate and their salts and quaternary compounds, and also vinyl esters such as vinyl acetate.

The polymerization is carried out by methods known per se. The initiation can be carried out thermally, photochemically, by radiation or by means of conventional radical initiators. The polymerization can be carried out in solution, suspension or emulsion. Suitable initiators are inorganic peroxides, such as hydrogen peroxide, or organic hydroperoxides and peroxides, such as tert-butyl-, cumene hydroperoxide or dibenzoyl peroxide, aliphatic azo compounds which break down into radicals, such as 2,2'-azo-bis-isobutyronitrile, redox systems, such as the persulfate or chlorate system with pyrosulfite or ferrous salts, and also transition metal chelates, which are known sources of radicals. The initiators are usually used in an amount of from 0.001 to 1% by weight, based on the amount of monomer. The optimum amount and type of optimally effective initiator are easily determined experimentally.

The polymerization is preferably carried out in the presence of a solvent or diluent. The suspension, solution and emulsion polymerization processes, which are common for other monomers, are also suitable for the production of polymers according to the invention. Optionally, auxiliary agents such as buffers, dispersants, protective colloids, etc. can be used. The polymers according to the invention can be used as flocculating, sedimenting, dewatering and retention agents. Characterized by solubility in water. In addition, their aqueous solutions have only low viscosity, which is very advantageous for their application. Due to the presence of very stable urea groups, these polymers also have excellent stability to hydrolysis.

The starting acryloyl and methacryloyl ureas are new substances that are obtained by the reaction of alkyl or acyl isocyanates with amides of unsaturated carboxylic acids at a temperature of about 20 to 140 °C and a pressure of 0.1 to 0.4 MPa in the presence of aromatic hydrocarbons or high-boiling ethers as solvents, after which the resulting halogen-substituted ureas are allowed to react with trialkylamines at a temperature of 20 to 100 °C and a pressure of 0.1 to 0.4 MPa in the presence of aliphatic and aromatic hydrocarbons, alcohols or ketones, preferably acetone as a solvent.

The invention is further illustrated by the following examples.

2146 8*3

Examples 1 to 5

Copolymers of acrylamide and monomers according to the invention (general prescription).

Acrylamide and cationic monomer are dissolved in water, the temperature of the solution is adjusted to 15 °C and the pH to 3.0. The solution is freed from oxygen by blowing with nitrogen (1 hour). 2,2'-azobis(isobutyronitrile) (AIBN), potassium peroxodisulfate and sodium dithionate and ferrous sulfate, listed in Table 1, are used as catalysts, after which the polymer starts immediately. The maximum temperature is reached after about 30 to 60 minutes. The mixture is allowed to cool, the resulting colorless gel is ground and freed from water with 2 to 3 liters of methanol. After filtration, the retained methanol is evaporated under vacuum. The yields are almost quantitative.

214883

Example Acrylamide Cationic Water Concentration Catalyst Na ₂ S ₂ O ₄ / Temperature Viscosity Molecular [g?] monomer [g] monomers AIBN K ₂ S ₂ 0g /FeSO ₄ [tag] [°C] 1% solution mass amount number in water [ °/o ] [ing] [ing] [taPa.s] focused o £ *« «$ > ac© ς© «ο

O O O

X X X X X

CM CO to CO CM rH CM t—I t-H

OOOOOO CM CM About About About About About 10 CM rH

oh

CM Tfl CM CM CM

O O O to to r-f CQ Μ Η rf co co co to lO o to o o ιο lO to lO to CM CM CM CM CM

OOOOO OOOOO what what what what what

XJ ce r-H

AS

WITH)

WHAT WHAT t> b. 05 .

OOOOO rH CO rH CO CM

O

O bO O O 05 C^ CO r-í

CM CO Tť lf5

2146 6 5

Example 6

The applicability of the polymers according to the invention as dewatering agents, for example for municipal sewage sludge, is illustrated by the two tests listed below. The dewatering time is measured by the CST (capillary suction time) method, see

1} R. Baskerville and R. Gale

A simple automatic instrument tor determining the filtrablity of sewage stodgas Water pollution Control 87 (19687, 233 to 241

2) R. Gale and R. Baskerville

Capillary Suction method tor determination of the filtration properties of a solid/liquid suspension Chemistry & Industry (1967), 355 to 356.

The results are shown in Table 2.

Table 2

Example

Viscosity of 1% solution in distilled water [mPa.s]

Capillary flow time when adding 0.1% solution in Krefeld tap water, [T _F (s)]

Addition 80 100 125 150 ppm

1 2 Product based on DMAEMA.CH3CI* 920 720 9000 Addition 71 100 45 50 150 40 200 21 11 30 3 2000 127 53 33 4 1040 74 32 14 Product based DMAEMA.CH3CI* 9000 200 63 22 ,

* DMAEMA == 2-dimethylaminoethyl acrylate

Despite the lower viscosity of the aqueous solutions, better results are achieved with the products according to the invention than with the copolymers based on DMAEMA.CH ₃ C1 used until now.

Example 7. The applicability of the products as drainage and retention aids in papermaking is illustrated by the tests described below carried out on standard pulp suspensions. . . .

Paper stock: 60% spruce sulphite pulp % hardwood pulp filler:···'-·' 30% SPS clay Grinding degree: 38 °SR

Dosage of the auxiliary agent: 0.02% based on the paper stock.

To determine the effectiveness of the products, the drainage time and retention effect are determined in a Schopper-Riegler grinding degree tester. The results are summarized in Table 3.

Table 3

Product

Drainage time [js]

Retention [)% ]

Blind test 25 72

Example 1 21 90

Example 2 18 89

Copolymer based

DMAEMA.CH3CI 29 91

DMAEMA = 2-(dimethylamino)ethyl methacrylate

It is clear that the products produced according to the invention are effective under test conditions which correspond well to the test methods in paper technology. For paper production it is advantageous that the said products are well fluid in aqueous solutions, so that they are easy to handle, well dosed and easy to dissolve.

Example 8

The products produced are tested as sedimentation agents in clarification. Clarification is carried out by adding an aluminum sulfate solution to an aqueous suspension of kaolin in water and adjusting the pH of the suspension to about 4.8. The sedimentation rate is measured, which is a measure of the flocculation properties in aqueous solution after the suspension is added to the clay. The results are shown in Table 4.

Table 4

Flocculation effect on a clay suspension containing 20 g solids per liter.

Product Additive quantity (ppm) Time (s)

Blind trial

Example

Example

Example

Example

Example

180

4.7

14.0

6.9

18.6

5.4

Literature:

H. Akyel and M. Neven, Chemistry-Ing. Technician 39 (1967), 172.

Claims (5)

OBJECT OF THE INVENTION A process for the production of unsaturated urea homopolymers and copolymers containing repeating structural units of the general formula -ca-CH ² i. what I ₊ . HN-CO-NH- (CO ^ (CH-NR j _{R i} wherein Z. X is either hydrogen or methyl, R is C 1 -C 4 alkyl, m is 0 or 1, n is an integer from 1 to 4 and Z is any salt-forming anion such as chloride, bromide, iodide, sulfate, perchlorate, nitrate or acetate, with the corresponding the copolymers contain from 4 to 96% by weight of said repeating units and the remainder consists of repeating units derived from at least one vinyl monomer which is copolymerizable with said compounds, characterized in that the unsaturated starting compound of the general formula (I): X, R, m, n and Z are as defined above, or they are subjected to polymerization by mixing them with other polymerizable monomers. 2. Method according to claim 1, characterized by. by copolymerizing unsaturated monomeric ureas of the formula I with water-soluble olefinically unsaturated monomers. 3. Process according to claim 2, characterized in that the water-soluble olefinically unsaturated comonomers are acrylamide, methacrylamide, N-substituted acrylic or methacrylamide derivatives, in particular N-dialkylamino derivatives, salts and quaternary compounds of these N-substituted derivatives, N-methylolacrylamide, N-methyl-methacrylamide, ethers of N-methylolacrylamide or -methacrylamide, airiinosubstituted esters of acrylic or methacrylic acid, including their salts and quaternary compounds or vinyl esters, or a mixture of at least two of the above compounds. 4. Process according to claim 1, characterized in that the polymerization is carried out by means of radical initiators. 5. A process according to any one of claims 1 to 4, wherein the polymerization is carried out in solution. (/; Severography, n., Plant 7, Mosl