DE1495744C - Process for the preparation of stable aqueous emulsions of ethylene copolymers - Google Patents

Description

3 4

water-soluble substances that form free radicals, 7 g potassium peroxydisulphate,

in particular inorganic per compounds, such as 13.7 g of 2-ethylhexyl maleic acid half-ester,

for example potassium, sodium or ammonium 60 g 1 N potassium hydroxide solution,

peroxydisulfate, perborate, hydrogen peroxide or 3.3 g see. Potassium phosphate,

others. The mentioned water-soluble per- 5 650 g ■ dist. boiled water
Connections can still be in the form of

Redox systems, ie in combination with Reduk-filled. After rinsing three times with about 20 atü tion media, 100 g of vinyl chloride and then ethylene are used in a manner known per se. Suitable reducing agents are, for example, pressurized up to a pressure of about 70 atmospheres, such as sodium pyrosulfite or bisulfite, sodium io. After heating to 70 ° C., within 30 minutes of minuformaldehyde sulfoxylate or triethanolamine. Here the pressure rises to around 130 atmospheres. You press initiator amounts of 0.1 to 3 percent by weight, ethylene up to a pressure of 200 atmospheres and based on the polymer, for the production of stable polymerized with thorough stirring for 14 ¹ Za hours. Sufficient in emulsions. "This time four times 50 g of vinyl chloride

The copolymerization is pumped up according to the present process. By recompressing ethylene if the pH is between 4 and 8 len, the pressure is between 180 and 200 atmospheres. keep. A total of 118 g of ethylene are used.

Since when using Alkaliperoxydisulfaten After cooling and releasing the pressure is obtained In the course of the polymerization, the hydrogen ions 918 g of a coagulate-free emulsion with a pH of 6 concentration of the reaction medium in the direction of 20 with 26 percent by weight solids content. That from it If lower pH values are shifted, it contains copolymers which can be isolated by coagulation for the purpose of education It is often advantageous to use higher yields, reacting 68 weight percent vinyl chloride, 5.3 weight ion medium Add buffer substances to one percent maleic acid half-ester and a 26.7 weight reduction of the pH value in a strongly acidic environment as a percentage of ethylene. The emulsion delivers when avoided. For this purpose, e.g. Borax or 25 dry on glass a clear, stretchable elastic secondary potassium phosphate. ■ Film that does not become cloudy when wetted with water

The interpolymerization according to the present is. 100 g of a process produced in a parallel experiment can be done with ethylene pressures of 30.2% emulsion with 0.18 g of Na above 10 atmospheres, but it is advisable to stir and press with trium alginate dissolved in 21.0 g of water carried out between 100 and 300 atmospheres. 30 left to stand for 24 hours. A cream pressures above 300 atmospheres are obtained, if necessary, with a solids content of 53.6 percent by weight,
borrowed, can also be applied. The temperature . . . _o .

depends on the initiator used in each case.

or initiator system. Polymerization in a 200-1 stainless steel high pressure autoclave is preferred

tion temperatures below 100 ° C, especially between 35 is a mixture of
see 50 »and 85 ° C. 0.865 kg potassium peroxydisulfate,

The process can be both discontinuously ₀ - _{7 kg of} maleic acid decyl half ester,

as well as run continuously. In the continuous _{014 k} potassium hydroxide (89 <Voig), '

The embarrassing procedure is initially an ah- 0.205 kg lake. Potassium phosphate,

proportional part of the aqueous phase and the monomers 40 _{91 0 k} dist. boiled water

presented and later to the extent that the poly ■

merization is progressing, more water filled. After rinsing three times at about 20 atm Phase and monomers via pressure locks in ethylene are pumped in 13 kg of vinyl chloride, introduced the reaction space. The polymerization is carried out at 70 ° C and

The 45 obtainable by the present process compress ethylene to a pressure of 180 to Emulsions are characterized by good film formation at 220 atmospheres. A total of 26.3 kg of ethylene are consumed. Coatings set by drying such. Half an hour after reaching the poly polymer emulsions can be obtained (e.g. in the merization temperature 13 kg Heat on glass), there are surprisingly strong vinyl chloride, 5.34 kg solution "P" (mixture of hydrophobic and completely clear. Also 50 0.7 kg of maleic acid decyl half ester, 0.14 kg of potassium Contact with water and aqueous liquid hydroxide - 89%, 4.5 kg dist. boiled water) This transparency is retained. pumped in.

The copolymer emulsions according to the invention After a total reaction time of 11 hours

are therefore particularly suitable for coating, or 137 kg of a 27.2% emulsion are obtained Impregnation of substrates such as B. wood, glass, 55 of a copolymer that is 65.5 percent by weight Metal, paper, fibrous materials (textiles), vinyl chloride, 3.5 percent by weight maleic acid decyl leather and others more. contains half the best and 31 percent by weight of ethylene.

In addition, these emulsions provided they

When drying, products with sufficient adhesive are used

deliver a good quality, for use on 60 .... . . . .

the adhesive sector. Polymerization is carried out analogously to Example I.

The 7 g of potassium peroxydisulfate given in the following examples,

Parts are parts by weight, unless otherwise stated. 15.4 g of abietyl maleate dissolved in

notices. 50 g of tert-butanol and

Example 1 ⁶ S ⁴⁰ S 1 N potassium hydroxide solution

■ 3.3 g see. Potassium phosphate,

In a stainless 1.3-1 high-pressure stirred autoclave ■ 710 g dist. boiled water,

becomes a mixture of 300 g vinyl chloride

at an ethylene pressure of 180 to 235 atmospheres at 70 ° C. A total of 121 g of ethylene are used. 1036 g of a 22.2% strength emulsion of a copolymer with 66.1% by weight vinyl chloride content are obtained, 6 percent by weight maleic abietyl half ester and 27.9 percent by weight ethylene.

Comparative example

A small cotton ball was attached to the forearm of seven male test persons, the with an emulsion of a copolymer of ethylene, vinyl chloride and maleic acid propyl half ester, prepared according to Example 4 of British Patent 989,678, -impregnated. After 24 hours the bandages were removed from the skin again. Symptoms of irritation could not be observed at first will. However, follicle swelling developed in two test subjects after one week with severe itching that lasted 3 to 5 days. 3 weeks after this first application, a similar experiment carried out. When the bandage was removed, there was no skin irritation this time either can be observed, but after 3 to 5 days there was strong in four subjects Reddening of the treated skin area and tender itching. Were the same subjects however, in the same manner as those described in Examples 1 to 3 of the present invention Emulsions made using 2-ethyl-hexyl-half-ester of maleic acid, Maleic acid n-decyl half ester or maleic acid dietyl half ester were treated, none of the above-mentioned irritation symptoms occurred.

Claims (1)

1 2 The maleic acid half-esters to be used have the Emulsions have a particularly good creaming behavior. Process for the production of stable water- The maleic acid half esters used are physiological rigen emulsions of copolymers, which consist of logically harmless. Let out the emulsions Ethylene, 50 to 70 percent by weight vinyl chloride 5 produce films that are completely transparent, and 2 to 10 percent by weight of maleic acid semi-incombustible or flame retardant and a very high esters exist, have low water sensitivity at pressures above 100 atü, even if and temperatures below 100 ° C in counter-very long-chain half-esters of maleic acid, the were water-soluble free radicals already reminiscent of emulsifier types, used Substances without the addition of conventional emulsifiers, io. characterized in that the invention relates to a process maleic acid half-ester from maleic acid and an aliphatic or cycloaliphatic, saturated for the production of stable aqueous emulsions, of copolymers made from ethylene, 50 to 70 gel-valent alcohol with at least 7 carbon weight percent vinyl chloride and 2 to 10 Atoms of weight is used and the polymerization consists of 15 percent maleic acid half esters, at pressures at ethylene pressures of 100 to 300 atmospheres and above 100 atmospheres and temperatures below temperatures of 50 to 85 ° C. 100 ° C is carried out in the presence of water-soluble free radicals. ^! forming substances without the addition of the usual emulsions gates, characterized in that a maleic acid 20 half esters of maleic acid and one saturated It is already a process for the production of aliphatic or cycloaliphatic oil-valent Alstabilen Aqueous emulsions of copolymers used alcohol with at least 7 carbon atoms of ethylene without the addition of conventional emulsifiers and polymerization at ethylene pressures under pressure with the help of water-soluble, free radii from 100 to 300 atü and temperatures from 50 to Calcium-forming substances have been proposed to be carried out at 25-85 ° C. after which ethylene is added in the presence of 50 to 70 Ge according to the preferred procedure parts by weight vinyl chloride and 2 to 10 parts by weight setting maleic acid half-ester with a 7 to of the salt of a half-ester of maleic acid and an alcohol compound containing 10 carbon atoms an aliphatic or cycloaliphatic lwertinent are characterized by a good creaming gen alcohol with a maximum of 6 carbon atoms in 30 th. of the alcohol component at pH values of 4 to 8, but it was observed that films and polymerized. Layers that are obtained from the emulsions produced according to the invention, which are very sensitive to storage and low water sensitivity, even if they are stable to shaking, show an excellent, very long-chain half-ester of maleic acid and film formation and deliver when drying on sub-aliphatic alcohols - which are already on emulsifier substrates, such as B. Glass, coatings of very types remember - are used
low water sensitivity. As a special third mixed polymerisation composite, if substrates made from fibrous materials, such as tex- nents of the present invention, are treated with the emulsions mentioned 40 esters of maleic acid and straight-chain or used and then over a longer period of time with the branched, saturated aliphatic or cycloaliphatic skin Contact with corneal alcohols containing at least 7 carbon atoms can, however, in some cases cause irritation of the carbon atoms. Appear as aliphatic alcohol and reddening of the skin. Such emulsions are n-heptanol-1, n-octanol-1, 2-EthyIhexasionen are therefore for use in this field 45 nol-1, 3,5,5-trimethylhexanol-1, n-dodecanoI, 2,2- not suitable. Dimethyl-decanol-1, n-tetradecanol-1, n-hexadeca-Next it is known from the British patent nol-1, abietyl alcohol and as cycloaliphatic 579 883, ethylene and vinyl chloride in aqueous alcohols cyclohexylmethanol, methylcyclohexanol, medium in the absence of emulsifiers to polymerize 3,3,5-trimethylcyclohexanol, borneol, isoborneol. In contrast to procedure 50 called menthol or decalol-2. The copolymers obtained from these alcohols or the present invention are - as mentioned above - preferably not obtained as a stable emulsion, since, as is evident from the British patent specification cited for the types containing 7 to 10 carbon atoms, is of particular interest. The product is expediently filtered after the polymerization, washed the acidic esters mentioned in the form of their salts and dried. · 55 in particular its alkali or ammonium salts, Finally it is used from the French patent. It is of course also known from writing 1 295 924, ethylene in the presence of a mix of the acids mentioned can be used,
of ethylenically unsaturated compounds with The amounts of the maleic acid half-carboxyl or sulfonic acid group to be used, such as esters, are limited by the desired properties of maleic acid half-esters with 1 to 18 carbon atoms in the 60 of the copolymer to be prepared. An ester alkyl to polymerize. Stable amounts as small as possible are required in order to obtain the emulsions which, after drying, give the polymers obtained water resistance or, however, opaque films. The coatings that can be achieved with the emulsions, on the other hand, are not reduced according to the invention. Accordingly, ethylene, vinyl chloride and 65 2 and K) percent by weight, preferably 3 and maleic acid half-esters with at least 7 carbon atoms 8 weight percent, of the above-mentioned maleic acid half-meter Esteralkyl copolymerized, with stable emulsifiers being copolymerized,
sions are obtained. Due to the special The initiation of the polymerization must by