DE3149201C2 - Emulsifier for emulsion polymerization and use of the emulsifier - Google Patents

Abstract

The invention relates to an emulsifier for emulsion polymerization, containing, as an effective component, a hemiamide alkali salt and / or a hemiamide alkali salt of succinic acid with a hydrocarbon radical with 8 to 30 carbon atoms.

Description

wherein R ^{1 is} a hydrocarbon radical having 8 to 30 carbon atoms, R ² and R ³ each represent hydrogen atoms or alkyl groups having] to 4 carbon atoms, or R ² and R ³ together form a five-membered or six-membered heterocyclic ring via the nitrogen atom, and X is Alkali metal or a substituted or unsubstituted ammonium group.

2. Use of the emulsifiers according to claim 1 in the production of polystyrene, styrene-butadicn rubber, Polyisoprene rubber, acrylonitrile butadiene styrene polymer, methyl methacrylate butadiene rubber or polybutadiene rubber in an amount of 0.5 to 10% by weight based on the incorporated put monomers.

The invention relates to an emulsifier for emulsion polymerization.

It is known to use resin acid soaps and fatty acid soaps as emulsifiers in the production of styrene-butadiene rubber, Isoprene rubber, butadiene rubber, chloroprene rubber and ABS resins over the To use emulsion polymerization. Of the known emulsifying agents, resin acid soaps in particular are z. B. the soaps of disproportionated rosin and hydrogenated rosin, due to the tackifying properties suitable so that the obtained synthetic rubbers and synthetic

Resins have better tack and processability properties. Since these emulsifying agents are soluble especially at low temperatures and at low ^temperatures for the polymerization Temperatuf are suitable are the properties of the rubbers, and resins in which they are processed in

generally sufficient. These known emulsifiers or emulsifiers, which are particularly useful in practice

are preferred, but have the disadvantage that they are not available in sufficient quantities because

the colophony as a natural product is not unrestrictedly accessible.

The invention is therefore based on the object of providing a synthetically producible emulsifier to provide, which can be used as a substitute for the known resin acid soaps and which is more effective for the Emulsion polymerization is employable as the rosin acid soaps and this contributes to shortening the polymerization time as compared with that of the rosin acid soaps. It is also desired an emulsifier that

is more effective and therefore used in smaller amounts than the resin acid soaps in emulsion polymerization can be.

The object is achieved by an emulsifier of the type indicated, which is characterized in that it is made from an alkali salt of succinic acid half-amide of the general formula 1 - as mentioned above - with a hydrocarbon radical with 8 to 30 carbon atoms for R ¹ as the active ingredient of the Emul-

greed.

There are intensive studies on the production of emulsifiers for emulsion polymerization have been carried out using chemically easily accessible starting materials and which nevertheless have very good properties as replacement products for resin acid soaps. It it was found that the salts of succinic acid according to the invention with the hydrocarbon radical from 8 to 30 carbon atoms can be used very well as emulsifiers for emulsion polymerization, and in fact in smaller ones Quantities than the known rosin acid soaps. The salts according to the invention are capable of the polymerization to accelerate, so that this is completed in a shorter time than when using the known Resin acid soaps is common. As shown in the accompanying FIG. 1, the emulsifying agents according to the invention have an effect a conversion of the monomer into the polymer in a time 50 to 60% shorter than when it is used of salts of disproportionated rosin (emulsifier "a") is the case.

In addition, the emulsifying agents according to the invention have the advantage that they, like the resin acid soaps, contribute are readily soluble at low temperatures and also as emulsifiers for polymerisation at low temperatures can be used because they decisively improve the stability of the latex formed. Also effect the emulsifiers according to the invention a suitable tackiness and processability of the obtained

Rubber or resin without adversely affecting the properties of these products. It is known that the alkali salt of substituted succinic acid can be used as an auxiliary dispersant in combination can be used with a resin acid soap or fatty acid soap for emulsion polymerization (cf. Japanese Patent Application Laid-Open No. 86 783/11978). The alkali salt of substituted succinic acid is, however,

when used alone for emulsion polymerization, it cannot be used as an effective emulsifier. The alkali salt also does not improve or accelerate the polymerization reaction. When the alkali salt of substituted succinic acid is used as the emulsifier, the rate of conversion is less than 50% of the conversion caused by the known rosin acid soaps. It was therefore particularly surprising that the succinic acid salts according to the invention have such a good effect on the polymerization.
The succinic acid salts according to the invention are salts of the general formula I

CNR ² R ³

C-OX

Il ο

where R 'is a hydrocarbon radical with 8 to 30 carbon atoms, R ² and R ³ each represent hydrogen atoms or alkyl groups with 1 to 4 carbon atoms, or R ^: and R ³ together form a five-membered or six-membered heterocyclic ring suspended from the nitrogen atom form, and X is an alkali metal atom or a substituted or unsubstituted ammonium group.

The preferred hydrocarbon radicals R ^{1 of} the general formula I are straight-chain or branched-chain alkenyl groups or alkyl groups, in particular those which have 10 to 25 carbon atoms, e.g. B. octenyl, nonenyl, nonyl, decenyl, dodecenyl, dodecyl, tetradecenyl, pentadecenyl, hexadecenyl, octadecenyl, octadecyl and eicosenyl. If the hydrocarbon radicals have fewer than 8 carbon atoms, the salt according to the invention has only a low level of effectiveness in terms of micelle formation. If the hydrocarbon radical has more than 30 carbon atoms, the salt according to the invention has only a very low solubility in water. In both cases, the emulsifiability of the salts according to the invention is reduced.

The alkyl groups R ² and R ³ are straight-chain or branched-chain alkyl groups, in particular methyl, ethyl, propyl, isopropyl and butyl. Examples of the heterocyclic rings which are formed from the radicals R ² and R ³ together with the nitrogen atom are, in particular, pyrrolidino, piperidino, piperazino and morpholines

The compounds of the general formula I in which at least one of the radicals R ² and R ^{3 is} a hydrogen atom tend to convert into imide compounds when the emulsifier is stored for a long period of time. For emulsifying agents that are to be stored for a long time, it is therefore preferred to use compounds in which neither R ² nor R ^{3 is} a hydrogen atom.

The alkali salts according to the invention, which are used as active ingredient components for the emulsifiers, are z. B. manufactured as follows:

An equimolar addition product of an olefin with a certain number of Carbon atoms and maleic acid used for the appropriately hydrogenated product thereof (alkenyl succinic anhydride or alkyl succinic anhydride). The starting material is made with ammonia, a primary Amine or a secondary amine reacted to produce the hemiamide in equimolar proportions, the then neutralized with ammonia or an amine to produce the ammonium salt. Alternatively the hemiamide can also be mixed with potassium hydroxide, sodium hydroxide or another alkali metal hydroxide can be neutralized to produce an alkali metal salt. According to the above procedure, the olefin is with

* "Maleic anhydride converted under the usual conditions, e.g. at temperatures of 150 to 280 ° C for

about 30 minutes to 10 hours in an open or closed reaction vessel. For the hydrogenation, the addition product is reacted under customary conditions. The reaction for the preparation of the monoamide is carried out at -30 to 150 ⁰ C, preferably 0 to 50 h at about ⁰ C, for 10 minutes to third The salt can also be used under usual conditions, e.g. B. at about 0 to 8O ⁰ C, are produced.

Suitable olefins for the above process are e.g. B. Oligomers of lower olefins, such as ethylene, propylene, Butene, isobutene, pentene, isopentene and witches. There are also a number of primary and secondary amines can be used for the above method, e.g. B. methylamine, ethylamine, propylamine and butylamine, and as secondary Amines e.g. B. dimethylamine, diethylamine, methylethylamine, dipropylamine, morpholine, piperidine, piperazine and pyrrolidine.

The emulsifiers according to the invention are suitable for emulsion polymerization, e.g. B. for manufacturing of various synthetic rubbers and synthetic resins, such as polystyrene, styrene-butadiene rubber, Polyisoprene rubber, acrylonitrile butadiene styrene polymer, methyl methacrylate butadiene rubber and polybutadiene rubber. Since the emulsifiers according to the invention in particular at low Temperatures are soluble, the emulsifiers are suitable for both emulsion polymerizations at low temperatures Temperatures as well as at high temperatures. Suitable polymerizable monomers for manufacture of synthetic rubbers and resins by means of emulsion polymerization are e.g. B. Acrylates, Methacrylates, styrene, vinyl chloride, butadiene, chloroprene and isoprene.

The emulsifiers according to the invention are used for the polymerization in amounts of about 0.5 to 10% by weight, preferably 1 to 5% by weight, based on the monomer used, is used. The one in emulsion polymerization Usable amounts of emulsifiers according to the invention are significantly smaller than the amounts.

which are necessary when using known resin acid soaps.

The emulsifiers according to the invention can - usually - also in combination with others
known emulsifiers can be used. However, the excellent properties are already then
achieved when the emulsifiers according to the invention are used alone. jk

example 1

A butylene oligomer (mixture containing 46% C, _r olefin, 15% Ci ₅ -OIeHn and 15% C ,, - OIefin) and maleic anhydride are subjected to an addition reaction to form a succinic anhydride (saponification number:
400), which is then treated with a sufficient amount of dimethylamine (in the form of a
s 50% aqueous solution) is ^{reacted at 10 to 20 0} C for 1 h, and the dimethylamine salt of the substituted succinic acid half-amide is formed. This salt is hereinafter referred to as "emulsifier A".

Example 2

The substituted succinic anhydride of example! 1 is dissolved in benzene, and then ammonia gas is added to
the solution was introduced into the door for 1 h, the temperature of the solution being kept at 20 to 25 ° C. The received
Precipitate is dried to produce the ammonium salt of the substituted succinic acid half-amide. B

(hereinafter referred to as "emulsifier B"). §

Comparative example 3

The substituted succinic anhydride from Example 1 is dissolved in 0.6 saponification equivalents of ethyl alcohol

get. The solution is then heated to the boiling point of ethyl alcohol for 1 hour for reaction. It becomes the Γ

Alcohol is distilled off from the reaction mixture in vacuo to obtain the ethyl half-ester of the substituted Siuccin- |

acid (acid number: 175). The Halbester is then neutralized by reaction with a entsprc- t

equivalent amount of chewing hydroxide to produce the potassium salt of the half-ester (hereinafter referred to as § '

»Emulsifier C«). | i

Example 4 ||

A propylene olefin (containing 76% C | ₂ olefin, 17% C _n olefin in mixture) and maleic anhydride ||

are subjected to an addition reaction to form the substituted succinic anhydride with a stranding j |

to produce number of 420, which then reacted with 0.5 saponification equivalents of diethylamine at 20 to 25 ° C sy

to produce the substituted succinic acid half-amide with an acid number of 170. The hemi-amide becomes |

then neutralized with sufficient equivalents of caudal hydroxide to neutralize the potassium salt of the |

Produce hemiamids (hereinafter referred to as "emulsifier D"). |

Example 5 f *

1

A butylene oligomer (containing 15% C ,, - ₁₂ -olefin, 19% C _13. ^ -Olefin, 62% C ₁₅ -I ₆ -OIeIm and 4% Ci ₇ - ^ - OIe-|

fin in a mixture) and maleic anhydride are subjected to an addition reaction to form a succinic acid |

to produce reanhydride with a saponification number of 351, which then with 0.5 saponification equivalents of dimethyl |

lamin is reacted at 10 to 20 ⁰ C in order to produce the succinic acid half-amide with an acid number of 186. |

The Haibarnid is then neutralized with sufficient equivalents of caudal hydroxide to neutralize |

to produce the potassium salt of hemiamide (hereinafter referred to as "emulsifier F"). I.

Example 6 j§

A Buttylenoligomer (containing 9% C _5-16 olefin, 16% C ₁₇ -] _8-olefin, 53% C _9-20 olefin, 11% C ₂₁ - ₂₂ olefin |

and 11% C ₂₃ . ₂₄ -olefin in mixture) and maleic anhydride are subjected to an addition reaction, |

to produce a succinic anhydride (saponification number: 263), which then with dimethylamine in Example 5 g

described manner is implemented to the substituted succinic acid half-amide with an acid number of 135 |

to divide. The amide is then treated with sufficient equivalents of sodium hydroxide for neutralization?

to produce the sodium salt of hemiamide (hereinafter referred to as "emulsifier G").

Example 7

The substituted succinic anhydride from Example 1 is hydrogenated, and then the product (saponification number: 397) is reacted with 0.5 saponification equivalents of n-butylamine at 20 to 25 ° C for 1 h to convert the hemiamide of
To produce alkyl succinic acid with an acid number of 165. The hemiamide is neutralized with sufficient equivalents of caudal hydroxide to make the hemiamide potassium salt (hereinafter referred to as "emulsifier H").

□ 5 Comparative example 8

The potassium salt of a commercially available disproportionated rosin is used as "emulsifier a".

Comparative example 9

The substituted succinic anhydride from Example 1 is neutralized with sufficient amounts for saponification Equivalents of an aqueous solution of potassium hydroxide to the dipotassium salt of substituted succinic acid to produce (»emulsifier b«).

Comparative example

The substituted succinic anhydride of Example 4 is neutralized in the same manner as in Comparative Example 2 to produce the dipotassium salt of substituted succinic acid (»Emulsifier c «).

Emulsion Polymerization Test:

The emulsifiers A to H according to the invention and the comparative agents a to c were used for emulsion polymerization used in the production of SBRaIs well-known synthetic rubber by means of the cold rubber process with a sulfoxylate formulation. The conversion to the SBR was with the individual Try for sure.

1. The materials used in the experiments are summarized in Table 1 below.

2. Polymerization conditions:
Temperature: 5 ⁰ C

Time: 6 h

In a nitrogen atmosphere

3. Conversion (in%) See table 2.

Table 1

Materials and means Table 2 Butadiene Parts by weight Monomer test Styrene 70 Deionized water (deaerated) 30th Dispersing medium Emulsifiers A-H or a-c 200 Emulsifier Naphthalene formaldehyde resin sodium sulfonate 4th Dispersants tert-dodecyl mercaptan 0.15 Crosslinking agents 0.245 Polymerization initiator: p-menthane hydroperoxide Oxidizing agent Iron sulfate (heptahydrate) 0.104 Reducing agent Sodium formaldehyde sulfoxylate 0.05 secondary reducing agent EDTA-4Na 0.15 Gelatinizing agents Sodium phosphate (dodecahydrate) 0.07 electrolyte 0.8 Emulsifier conversion coagulation educational (%)

1 2 3 4 5 6 7 8 9 10

81.3 74.1 72.8 73.3 71.5 79.0 68.0 60.0 27.2 25.4

0.3 0.4 0.4 0.3 0.7 0.3 0.4 0.9 0.4 0.5

4. Latex stability

The entire amount of the latex obtained during the polymerization is placed in a 500 ml three-necked flask, and then steam is introduced to remove the unreacted butadiene and styrene. The unusual one Coagulate is filtered off in a stainless steel sieve with a mesh size of 0.18 mm and then combined with the coagulum formed during the polymerization. The combined coagulates are dried. The ratio of the formation of coagulum is calculated using the following equation to determine the latex stability. The smaller the determined value, the greater the stability of the latex.

Coagulation ₌ dry weight of the total _{coagulate (g) χ} , _Q0

Formation rate (%) Dry weight of total rubber (g)

The results are shown in Table 2.

Emulsifiers A, C and a were tested in the same manner as above but with the above Except that the reaction time was 3 hours and 4.5 hours, respectively, in order to then contrast the corresponding conversion to determine a reaction time of 6 h. The Fi g. 1 shows the results using the emulsifying agents A, C and a. The results in Table 1 show that the emulsifier according to the invention is much more effective in terms of shortening the polymerization time than the alkali salt of disproportionated rosin, which is one of the best known common emulsifiers (emulsifier "A"), as well as the potassium salt a half ester of succinic acid.

Example 11

The substituted succinic anhydride according to Example 1 is reacted with 0.5 saponification equivalent Dimethylamine (50% aqueous solution) at 5 to 10 ° C for 1 h to remove the half-amide of the substituted succinic acid with an acid number of 181. The hemi-amide is then neutralized with sufficient amounts for neutralization Equivalents of potassium hydroxide. To make the potassium salt of hemiamide (hereinafter referred to as "Emulsifier I").

The emulsifier I became the same in terms of its effectiveness in emulsion polymerization Examined manner as indicated above, with the exception that two parts by weight of the emulsifier were used. It was found that the conversion was 61.0% and the rate of coagulation formation was 0.5% (Test 12).

Evaluation of the rubber

The following compositions were prepared in accordance with JIS K 6383, with the rubber, according to test 8, the rubber according to test 12 and a conventional SBR 1500 rubber were used. The composition was on a roller mill with rollers 45.7 cm in length and diameter 8 inches wide according to ASTM D 3185-75 to make the rubber compound.

Mixing process

The speed of rotation of the front roller was 18 rpm.

The ratio of the speed of rotation from the front to the rear roller was 1: 1.25.

The roller frame temperature was 50 ± 5 ^° C.

Components of the composition

SBR 100 Wt% Stearic acid 1 Wt% zinc oxide 3 Wt% accelerator 1 Wt% (Cyclohexyl-benzo- thiazolesulfenamide) sulfur 1 , 75% by weight Soot (HAF) 50 Wt%

The properties of the rubbers produced in this way are summarized in the table below. The search results show that, when 2 parts of the emulsifier according to the invention are used, rubbers obtained that have good properties that are comparable to the properties of rubbers, in which 4 parts by weight of a known disproportionated rosin and one commercially available SBR were used.

No. 31 49 201 12th SBR
(commercially available) Table 3 94 85 rubber 8th No. Mooney viscosity
(MLi ₊₄ : 100 ± 1 ° C) 64 86 59 Mooney scorch *) 27 ^C 45 ^m 28 ° 00 "' Min. Viscosity 45 ^C 62 50 ^m 48 ° 45 "' Min. Viscosity time 62 ^C 30 ^m 17 ° 40 "' 63 ° 20 "' t5 30 ^m 27 ° t35 , ₄₅ m 32 =

*) Large rotor, preheating for 1 min. To 125 + 1 ° C Test method: Mooney, JIS K6300-1974

Table 4

Rubber No. 8 No. 12 SBR

Vulcanization time (145 ± 1 ° C, min) 45 20 45

Unaged:

Tensile strength (kp / cm ² ) elongation (%)
Hardness [Hs (JIS A)]
300% modulus (kp / cm ² ) tensile strength (kp / cm)

Aged: (Gearofen, 70 ± I ⁰ CX 96 h) Change in tensile strength (%) Change in elongation (%) Change in hardness [Hs (JIS A)] Change in 300% modulus. (%)

Vulcanization temperature: 145 ± 1 ° C Test method: JlS K6301-1973

276 287 290 470 500 490 70 69 68 176 160 161 48 45 53 +7.8 -i, o +0.2 -26.2 -27.8 -26.3 +3 +8 +3 +47.4 +43.8 +42.1

1 sheet of drawings

Claims (1)

Patent claims: 1. Emulsifier for emulsion polymerization, consisting of a succinic acid half-amide alkali salt of the general formula I. (U C-OX O