HU205150B - Process for producing polymeric dispersions by using premulsion - Google Patents

Abstract

During emulsion polymerisation (in this case) preemulsified monomers are added in small doses to an aq. catalyst soln. at 70-85 deg. C. Conventional anionic and nonionic surfactants were used for the preemulsification stage 1-10 wt.% (based on monomers) of another emulsifier is added to the reaction mixt. This emulsifier is an adduct of a styrene-maleic-acid-anhydride copolymer (mol wt. 1400-2500; acid no: 270-480 -mg KOH/g) and/or of a partial ester of styrene-maleic-acid anhydride-copolymer with a 1-200 alcohol (mol. wt. 1700-2500; acid no: 210-230 mg KOG/g)- and fatty acid esters of oxyethylated multifunctional aliphatic alcohols and/or of fatty acid polyethylene esters and/or of oxyethylated fatty acid alcohols, and/or oxyethylated-alkyl-phenols. The adduct is neutralised by an alkali and the soln. of adduct contains 18-28 wt.% solids. The final reaction mix is agitated for 2-3 hours at 70-85 deg. C and the resulting polymer dispn. is neutralised by an alkaline soln. - (Dwg.0/0)

Description

The present invention relates to a process for preparing polymeric dispersions using a monomeric pre-emulsion.

Dispersions of monomers by emulsion polymerization are widely used as film-forming materials in the lacquer and paint, leather, paper and textile industries. (H. Qarson: The Applications of Synthetic Resin Emulsions, E. Benn Ltd. London 1972). For this type of film-forming material, the need for a good water and chemical resistance of the coating, as well as the possibility of high coating brightness and, consequently, of small particle size, and a safer and longer shelf life of the products is a prominent requirement. These properties are highly dependent on the type and amount of emulsifiers and protective colloids used in the emulsion polymerization. .

Most commonly, anionic and nonionic surfactants are commonly used to form polymeric dispersions by emulsion polymerization. The ethylene oxide compounds of fatty acids, fatty alcohols, alkyl phenols and the ethylene oxide are the most commonly used anionic type as the anionic type.

Technologically, the preparation of polymer dispersions is generally accomplished by the simultaneous addition of two liquids to the reactor, ensuring a uniform, uniform addition of a stream of monomers essentially free of initiator. Such processes are described in U.S. Patent Nos. 4,101,490 and 3,965,032 and British Patent 118,725.

However, a so-called pre-emulsion technology is known for producing polymer dispersions, in which a pre-prepared aqueous pre-emulsion of monomers is continuously added to the manufacturing apparatus. An advantage of this process is that reproducible and small particle size can be achieved by adding a single fluid stream - there is no need to coordinate two fluid streams depending on technological parameters.

Hyen's technology is used to produce mainly polymeric dispersions based on vinyl acetate and vinyl acetate. Methods of pre-emulsion technology are described in U.S. Patent Nos. 4,081,416, 4,137,205 and 4,171,407.

A common feature of such processes is that the anionic and nonionic surfactants are used instead of the protective colloid to ensure dispersion stability. However, to improve unsatisfactory frost stability, a few percent of the carboxyl-functional monomer, e.g. acrylic acid is added to a mixture of copolymerization reaction.

In our experimental work, we have found that the emulsifiers of the preemulsion technology can be significantly enhanced by using an emulsifier containing from about 1400 to about 2500 moles / kg of an emulsifier in the range of 1400-2500 mole%, based on the total amount of monomers in the preemulsion. g of a styrene-maleic anhydride copolymer and / or a partial ester of a styrene-malemic anhydride copolymer with a carbon number of 120 carbon atoms with fatty acid esters of oxyethylated polyhydric aliphatic alcohols and / or with fatty acid polyethylene and / or solution.

The use of a specially formulated adduct used in the present invention results in a final product with improved properties in polymerization compared to the use of known styrene-maleic anhydride copolymer emulsifiers.

By styrene-maleic anhydride copolymers is meant a polymer having a molecular weight of 1400-2500, preferably 1600-1900, having an acid number of 270-480 mg KOH / g, wherein the molar ratio of maleic anhydride to styrene ranges from 1: 1 to 1: 3.

Partial esters of styrene-maleic anhydride copolymers with C 1-20 alcohols are understood to mean polymers having a molecular weight of 1700-2500, melting point 100-170 ° C, 105-270 mgKOH / g.

Amongst the styrene-maleic anhydride copolymers and their partial esters, the polymer preferably has a molecular weight of 1800-2800, melting point 135-150 ° C, and an acid number of 210-230 mg KOH / g.

The following compounds are preferably used to prepare the partial ester adduct of the styrene-maleic anhydride copolymer and / or the styrene-maleic anhydride copolymer:

(a) ethylene oxide adducts of fatty acid esters of polyhydric alcohols. Thus, esters of trivalent (e.g., glycerol, trimethylolpropane), tetravalent (e.g., pentaerythritol, anhydrosorbite), divalent (e.g., ethylene glycol, propylene glycol) esters of C16-18 saturated or unsaturated fatty acids are ethoxylated,

(b) polyethylene glycol esters of fatty acids: monoesters of C16-C18 saturated and unsaturated fatty acids with 2-40 ethylene oxide units,

(c) ethylene oxide adducts of fatty alcohols: ethers of saturated and unsaturated fatty alcohols having from 10 to 20 carbon atoms containing from 2 to 30 units of ethylene oxide,

d) alkylene phenols may be ethylene oxide adducts: ethers containing from 8 to 40 ethylene oxide units of C8-C18 alkyl phenols.

The adduct of the partial ester of the styrene-maleic anhydride copolymer with oxyethylated alkyl phenols is particularly preferably used as emulsifier in the process of the invention.

Among the oxyethylated monoalcohols, the ethers of octyl and nonylphenols containing from 10 to 25 ethylene oxide units are preferred.

Among the known emulsifiers used in the emulsion polymerization reaction, the alkyl

EN 205 150 Β -ols ethylene oxide adducts, C 10 -C 18 alkyl dialkyl sulfosuccinates, C 8 -C 18 alkyl chain, and 2 to 40 ethylene oxide units (alkyl phenol polyethylene glycol ether) sulfates ammonium salts.

In the process of the present invention, an emulsifier is used wherein 20-50% by weight of the acid groups of the partial ester of styrene maleic anhydride and / or styrene-maleic anhydride, preferably 4050% by weight, are reacted with the oxyethylated compound at 120-180 ° C. and then stirring the developer with 10-50% by weight of 28% ammonium hydroxide solution at 100-150 ° C relative to the starting materials until complete dissolution of the material.

Examples of the monomer include esters of vinyl monocarboxylic acids with C 1 -C 18 monoalcohols, preferably methyl acrylate, butyl acrylate, methyl methacrylate, vinyl monocarboxylic acid amides, preferably methacrylamide, aromatic vinyl hydrocarbons, C 1 -C 18 vinyl monocarboxylic acids and their vinyl esters, preferably acrylic acid, methacrylic acid, etc. employed.

Vinyl monomers are pre-emulsified by the addition of anionic and nonionic surfactants and water under intense mixing. The monomeric pre-emulsion is added portionwise to the 70-85 ° C aqueous catalyst mixture and then mixed with 1-10% by weight of the total amount of monomer emulsifier adduct of the present invention, 18-20% by weight. aqueous solution, the reaction mixture is then stirred at 70-85 [deg.] C. for 2-3 hours, then the aqueous polymer dispersion is neutralized with a reaction solution, preferably ammonium hydroxide solution, then filtered and removed. »

The dispersion according to the invention has the advantage that the coating made of it has increased frost resistance and abrasion resistance.

The following examples illustrate the process of the invention.

EXAMPLE 1 Styrene-maleic anhydride copolymer having a molecular weight of 1600 and having an acid number of 480 mg KOH / g and 100 parts by weight of 6 ethoxy units of oxyethylated sorbitol tetra (tallow oil ester) up to 110 mg KOH / g acid The reaction mixture is stirred under stirring and then cooled to 90 ° C, 350 parts water and 20 parts 28% ammonium hydroxide solution are added. The system is then stirred for 60 minutes at 130 ° C until complete dissolution of the styrene-maleate dicarboxylated sorbitol ester adduct.

Example 2 Partial ethyl ester of styrene-maleic anhydride copolymer having a molecular weight of 1900, 275 mg KOH / g, 20 parts by weight of ethyl acetate and 20 parts by weight of 20 parts of ethoxy acid in a styrene-maleic anhydride copolymer of molecular weight 1700 Polyethylene glycol ester is stirred at 160 ° C to 65 mg KOH / g acid with stirring and then cooled to 90 ° C, 440 parts water and 10 parts 28% ammonium hydroxide solution are added and 60 minutes The system is stirred at 135 ° C until the adduct formed is completely dissolved.

Example 3 Partial stearyl ester of styrene maleic anhydride having a molar weight of 1700, 270 mg KOH / g acid, 80 parts by weight of oxyethylated sorbitol penta (tallow oil ester) and 40 parts by weight of lauryl alcohol containing 8 parts of ethoxy. Polyethylene glycol ether was reacted at 150 ° C with stirring until 6 L of KOH / g acid was added, then cooled to 90 ° C, 400 parts water and 10 parts 28% NH ₄ OH solution added, followed by 60 minutes The system is stirred at 125 ° C until the adduct formed is completely dissolved.

EXAMPLE 4 Partial ethyl ester of styrene-maleic anhydride having a molecular weight of 1900 having an acid number of 220 mg KOH / g and 155 parts by weight of nonylphenol polyethylene glycol ether containing 23 units of ethylene oxide is reacted with stirring to 150 mg Con. then cooled to 90 ° C, 600 parts water and 6 parts 20% NH ₄ OH solution were added and the system was stirred at 130 ° C for 60 minutes until the adduct formed was completely dissolved.

Example 5

All were carried out as in Example 1, but using 108 parts by weight of 30 ethoxy units of oxyethylated propylene glycol monostearate instead of 100 parts by weight of oxyethylated sorbitol tetra (tallow oil ester).

Example 6

All proceed as in Example 2, but using 31 parts by weight of 6-ethoxy units of polyethylene glycol palmitic acid instead of 70 parts by weight of 20 parts of stearic acid-polyethylene glycols.

Example 7

Each was prepared as in Example 1, but using 50 parts by weight of 30 ethoxy units of oxyethylated propylene glycol monostearate and 19 parts of 6 ethoxy units of palmitic acid polyethylene glycol ester instead of 100 parts by weight of oxyethylated sorbitol (tallow oil ester).

HU 205 150 Β

Example 8

All proceed as in Example 3, but using 12.5 parts by weight of 6-ethoxy-unit polyethylene glycol ester of palmitic acid instead of 80 parts by weight of oxyethylated sorbitol penta (tallow oil ester). 5

Example 9

All proceed as in Example 3, but using 57.5 parts by weight of polyethylene glycol ester of palmitic acid instead of 57.5 parts by weight of oxyethyl sorbitol penta (tallow oil ester).

Example 10

Each was prepared as in Example 3, but using 24 parts by weight of ethylene glycol ether with 20 parts by weight of ethoxy instead of 12 parts by weight of oxyethylated lanyryl alcohol polyethylene glycol ether.

1Lpélda

All proceed as in Example 3, but using instead of the 20 oxyethylated alcohols used, a total of 26 parts by weight of allyl alcohol polyethylene glycol ether containing 8 ethoxy units.

Example 12 25

All proceed as in Example 4, but using dinonylphenol polyethylene glycol ether containing 93.5 parts 9 ethylene phenoxide units instead of 155 parts by weight of oxyethylated nonylphenolpolyethylene glycol ether. 30

Example 13

All proceed as in Example 4, but employing instead of 155 parts by weight of oxyethylated nonylphenol polyethylene glycol ether, 39 parts by weight of a polyethylene glycol ester of palmitic acid and 100 parts by weight of 40 parts of ethoxy in nonylphenol polyethylene glycol. .

Example 14 40

All proceed as in Example 4, but employing, instead of 155 parts by weight of oxyethylated nonylphenol polyethylene glycol ether, 45.5 parts by weight of lauryl alcohol polyethylene glycol ether containing 8 parts of ethoxy 'and 45 parts of nonylphenol polyethylene glycol containing 100 parts by weight of ethoxy units. .

Example 75

All proceed as in Example 4, but replacing 155 parts by weight of oxyethylated nonylphenol-50 polyethylene glycol ether with 110 parts by weight of 6 ethoxy units of oxyethylated sorbitol (tallow oil ester) and 100 parts of 40 ethoxy units of nonylphenol polyethylene glycol. -éterthasználunk.

⁵⁵ (Comparative) Example

Preparation of a polymer dispersion

180 parts by volume of distilled water, 1 part by weight of sodium salt of dioctylsulfosuccinate, 0.25 parts by weight of potassium persulphate (T. Solution) are charged into a stirred tank reactor.

Weigh into a separate vessel 340 parts by weight of distilled water, 1.0 parts by weight of the sodium salt of dioctylsulfosuccinate, 11.5 parts by weight of 23 ethylene oxide, nonylphenol polyethylene glycol ether, 1.8 parts by weight of potassium persulphate, 2 parts by weight of borax. adjust the pH of the Blended System to 5.5 with glacial acetic acid and add 9 parts by weight of acrylamide (Π.οΐdat). To solution H, premixed mixture of monomers (330 parts vinyl acetate and 110 parts vinyl formate) (HL solution) was added with stirring.

stirring for 900 minutes at 900 rpm produces a preemulsion of the monomers. Subsequently, solution I in the apparatus is heated to 80 ° C and the pre-emulsion is added at a constant rate for 3 hours. The system is then stirred at 80 ° C for 2 hours. Subsequently, it is cooled to 40 ° C with 28% w / w ammonium hydroxide solution to pH 7 and filtered through a 50 µm filter to form the resulting emulsion.

Example 17

All proceed as in Example 16, after adding the dea preemulsion to solution I, 40 parts by weight of the adduct of Example 2 are added to the system and then stirred at 80 ° C for 2 hours. The procedure of Example 16 is then followed.

Example 78

All proceed as in Example 17, but after adding the pre-emulsion, 1 part by weight of the emulsifier of Example 4 is added to the system.

Example 19

Example 18 was used in all but Example 12 was used instead of Example 4 adduct.

Example 20

All proceed as in Example 17, but after the addition of the pre-emulsion, 2 parts by weight of a partial ethyl ester of 270 mg KOH / g styrene-maleic acid copolymer having an acid number of 270 were added.

Example 27

Measure the values shown in Figs. antifreeze. Antifreeze is characterized by the number of alternating cycles during which consistency change, coagulation, does not occur.

Alternating cycles: -20 'C for 8 hours and then +20' C for 16 hours.

Then, in Figure 16-19. from the dispersion of Example 1A, and measuring the abrasion resistance of the paint coatings as described in DIN 53778/2.

The composition of the paint compositions is as follows: 16-20. The dispersion of Example 1 is 100.0 parts by weight

_2, 40.0 parts of rutile T1O

CaCO ₃ 375.0 parts by weight

Kaolin 80.0 parts by weight

HU 205 150 Β

talc 50.0 parts by weight Naphtha 10.0 parts by weight Water 350.0 parts by weight Sodium tripolyphosphate 4.0 parts by weight anti-foaming 2.0 parts by weight Chloroacetamide 2.0 parts by weight ethylene glycol 20.0 parts by weight Methyl hydroxy ethyl cellulose 4.0 parts by weight 1037.0 parts by weight

The measurement results are as follows;

Measurement 16.pl. 17.pl. 18.pl. 19.pl. 20.pl. Frost resistance (number of cycles) 1 17 9 4 2 / Wet abrasion (number of cycles) 220 1500 1800 800 500

The test results show that the dispersions of the present invention have improved frost resistance and abrasion resistance.

Claims (2)

1. A method of using polymer dispersions pre-emulsion according to which vinyl monomerekből-, anionic surfactant and nonionic surfactant, and water is prepared pre-emulsion by brisk stirring, then adding the pre-emulsion in small portions 70-85 ^o C ^and the aqueous catalyst solution with constant stirring , characterized in that the monomers 1 to 20% by weight of a neutralized aqueous emulsifier adduct solution containing from 18% to 20% by weight of a dry substance containing from 105 to 4800 molar weight of styrene-maleic anhydride copolymers having a molecular weight of 1400 to 2500, and / or the copolymer. An ethoxylated product of a partial ester of a C 20 aliphatic alcohol and a C 16-18 fatty acid ester of a polyhydric aliphatic alcohol with 2-40 ethylene oxides and / or a C 16-18 15 fatty acids with 2 to 40 ethylene oxide monoesters and / or 10 to 20 carbon fatty alcohols having 2 to 30 ethylene oxide units and / or 20 to 40 ethylene oxide ethyl ether containing 20 to 40 ethylene oxide units. and then to the resulting donuts It is prepared by neutralization with 10-50% by weight of aqueous alkaline solution. Process according to claim 1, characterized in that it has a molecular weight of 1900 and an acid number of 270 mg KOH / g. The adduct formed from the partial ethyl ester of 25 styrene-maleic acid copolymers with oxyethylated nonylphenol is used as emulsifier.