DE1125169B - Process for the production of plastics - Google Patents

Description

Process for the production of plastics It is known unsaturated Compounds such as butadiene, isoprene, styrene and x-methylstyrene with alkali metals, Alkali alkylene and alkali hydrides form high molecular weight compounds that contain the alkali metal contained in organometallic bond, ionically polymerize and then the obtained high molecular weight organometallic compounds with carbon dioxide, acidic esters, Aldehydes, ketones or alkylene oxides in the manner of an organometallic synthesis implement, resulting in polymers containing carboxyl and OH groups.

It is also known to use unsaturated hydrocarbons with such To polymerize radical formers that contain functional groups, such as. B. with azoisobutyric acid ester or hydrogen peroxide.

This results in polymers which contain the functional groups contain the radical formers bound and their functional groups, if they are not already present as OH groups, as in the case of hydrogen peroxide, converted into such can be. These polymers accordingly represent mixtures of more or less branched high molecular weight monohydric and polyhydric alcohols.

It is also known high molecular weight compounds that contain OH groups carry to react with diisocyanates to form polyurethanes. Also those mentioned, through radical polymerization obtained high molecular weight polyhydroxyl compounds has been reacted with diisocyanates to form polyurethanes.

In contrast, the present invention relates to the use of polyhydroxyl compounds obtained by ionic polymerization are.

One according to the prior art from a copolymer obtained by free radicals Polyurethane elastomer produced as a polyhydroxyl compound shows properties in particular a tensile strength according to DIN 53504, an elongation at break according to DIN 53504, a pin tear resistance according to DIN 53506 and a tear strength according to DIN 53513, which are clearly inferior to the process products of the present invention are.

The method of the present invention for making plastics including foams and fabrics based on polyhydroxyl compounds, Polyisocyanates and optionally crosslinking agents with shaping consists in that polyhydroxyl compounds are used which are obtained by a) ionic polymerization olefinic monomers with alkali metals or bifunctional alkali metal organic Compounds to high molecular weight bifunctional organometallic compounds, b) reaction of these high molecular weight organometallic compounds with alkylene oxides, Aldehydes or ketones to high molecular weight dialcoholates and c) hydrolysis of these to the free polyhydroxyl compounds have been obtained.

As olefinic monomers, which can be used individually or in a mixture in anionic Polymerization can be converted into high molecular weight organometallic compounds, are for example: butadiene, isoprene, 2-ethylbutadiene, 2-isopropylbutadiene, 2-phenylbutadiene, 2,3-dimethylbutadiene, styrene, methylstyrene, o-, m- and p-methylstyrene or vinyl chloride.

The alkali metals are potassium and especially lithium and sodium in question. Bifunctional organic alkali metal compounds are those which which contain 2 metal atoms in the molecule.

First and foremost, those compounds should be mentioned in which at least one of the two alkali atoms present in each molecule in the allyl position to one aromatic nucleus or a double bond, such as. B. p-xylylene-dilithium or disodium, the 9,10-disodium compound of 9,10-dihydroanthracene and des 9,10-dihydrophenanthrene, or the 1,2- or. 1,4-disodium compound of 1,2- or 1,4-dihydronaphthalene or very particularly the dilithium and disodium compounds of dimers and oligomers of the above-mentioned unsaturated compounds consisting of the alkali metals and the monomeric unsaturated hydrocarbons z. Am Presence of certain ethers or polynuclear aromatic compounds available are.

As compounds with the high molecular weight organometallic compounds to be converted to dialcoholates are: alkylene oxides, such as ethylene oxide, Propylene oxide, butadiene oxide, cyclohexene oxide, phenoxypropylene oxide, glycidyl allyl ether, N-methyl-N-phenylamino-propylene oxide, or aldehydes such as formaldehyde, acetaldehyde, Propionaldehyde, isobutyraldehyde, oenanthaldehyde, benzaldehyde, p-N, N-dimethylaminobenzaldehyde, and ketones such as acetone and methyl ethyl ketone. Among these are the alkylene oxides preferred because they do not lead to aldol condensations under the reaction conditions tend.

The use of ethylene oxide is particularly advantageous because it leads to primary alcohols and the use of amino-epoxides and amino-aldehydes, which do not carry any hydrogen atoms on the nitrogen, because the amino group causes the later reaction of the isocyanates with the neighboring OH group is accelerated. Finally, aminoaryl radicals and aryloxy radicals act as internal anti-aging agents in the case of the still unsaturated polymers.

As polyisocyanates that reacted with the high molecular weight dialcohols are, for example, the NCO groups having aliphatically bonded, such as butane-1,4-diisocyanate, hexane-1,6-diisocyanate, 3-oxaheptane-1,7-diisocyanate, 3-thloheptane-1,7-diisocyanate, cyclohexane-1,4 and 1,3-diisocyanate, 4,4'-methylene-bis-cyclohexyl isocyanate and p-xylylene-w, w'-di isocyanate, or aromatic diisocyanates such as phenylene-1,3- and -l, 4-diisocyanate, 4-chlorophenylene-1, 3-diisocyanate, triphenylmethane triisocyanate, 4,4'-diphenylene diisocyanate, 3,3'-dinitrodiphenylene-4,4'-diisocyanate, diphenylmethane-4,4'-diisocyanate, Diphenylsulfone-4,4'-diisocyanate, naphthylene-1,5-diisocyanate, or aromatic-aliphatic Diisocyanates, such as. B. p-B-Iso called cyanatoethyl phenyl isocyanate. Also isocyanate releasers from these polyisocyanates may be mentioned.

For the production of high molecular weight bifunctional organometallic Compounds which should expediently have a molecular weight of 700 to 12,000, can be the olefinic monomer or a mixture of several monomers in the presence or absence of inert solvents with the required molecular weight to achieve the necessary amount of the finely divided alkali metal are mixed at once, or it can first remove the alkali metal by adding a relatively small amount dissolved on olefinic monomers as a dialkali metal compound of the di- or oligomer be, whereupon the remainder of the olefinic monomers necessary to achieve the Molecular weight is necessary, is added all at once or successively.

Going through the dialkali metal compound stage of the oligomer represents a preferred special case of the use of difunctional alkali metal organic Compounds with a molecular weight between 60 and 600 as starters for the Polymerization. The use of the low molecular weight difunctional alkali metal compound allows much better than the block and solvent polymerization with the free alkali metals the exact setting of the desired molecular weight and also more uniform in terms of molecular weight Products than the polymerization with free alkali metals or even more than that Radical polymerization. That is especially for the later implementation of them manufactured High molecular weight dialcohols with diisocyanates are important because they are low Proportions of dialcohols that have a much higher molecular weight than corresponds to the average molecular weight in the reaction with the isocyanates lead to a too rapid increase in viscosity and thus the gelling or Shorten the casting time undesirably. The selection of high molecular weight organometallic Compounds and the "dialcohols" obtained from them are due to their special characteristics Suitability for the isocyanate polyaddition process, as this is due to its steric Structure and their uniformity to form urea and / or urethane groups Polymerization products with particularly regular spacing of the urea and / or Lead urethane groups. Because the polymerization is associated with a great deal of heat is, must be ensured by suitable cooling systems that the released Heat is dissipated well. In most cases, the reaction temperature is temperatures between -80 and 130 "C depending on the type of polymerization initiator used, the monomers and the solvents into consideration. So needed the polymerization with free alkali metals generally higher temperatures because of the greater Latency times than those with the difunctional alkali metal compounds, while in The presence of ethers causes the polymerization to be powers of ten faster in both cases expires. The temperature used also depends on the desired temperature steric structure of the high molecular weight »dialcohols«, since the steric structure is outside on the type of monomer, the alkali metal used and the solvent added is also determined by the reaction temperature. By choosing suitable reaction partners and reaction conditions, as is known for high molecular weight elastomers, also here in hand to polymerize stereospecifically. With service one can do so the polymerization in the direction of the pure trans-1,4-, cis-1, P, 1,2- or 3,4-polymerization or in the case of olefins in the direction of syndiotactic, isotactic or atactic polymers to steer. So you get z. B. with lithium (or lithium compounds) and isoprene in Absence of ethers difunctional metal compounds with Polycis-1,4-structure, while in the presence of ethers the 3,4 structure predominates.

According to the proportion of aromatic monomers, the polymerization products can be used with less than about 50% aromatic monomer more than those with more than about 50% of aromatic monomers differ, the former essentially provide Elastomers, while the latter essentially lead to plastic plastics.

The molecular weight of the high molecular weight organometallic compound depends on the ratio of the amount of low molecular weight organometallic used Compound (MD) to the amount of the reacted monomer (MM) and can easily according to the can be calculated using the following formula: Molecular weight = 2 MM + MG Nn where ND for the number of alkali metal equivalents in the low molecular weight difunctional Alkali metal compound are included. When using free alkali metals as a polymerization starter takes the place of the amount of low molecular weight organic alkali metal compound is the amount of reacted during the polymerization Alkali metal.

Because of the viscosity of the high molecular weight) 'dialcohols' and for the most favorable processing conditions will be those molecular weights of the high molecular weight Dialkali metal compounds which are between 900 and 6000 are preferred.

Implementation of the high molecular weight bifunctional organometallic Compounds with the alkylene oxides, aldehydes or ketones are best made in in a kneader or in a screw with the exclusion of moisture and air, if possible immediately following their production. The alkylene oxides and carbonyl compounds are generally in equivalence or in a slight stoichiometric excess via the metal functions of the high molecular weight compound, optionally dissolved in suitable inert solvents, at room temperature or slightly different Temperatures added.

This implementation is just as spontaneous and associated with a great deal of heat like the polymerization of the monomers.

The alcohols formed are by adding water, acids or Salts of strong acids hydrolyzed with weak bases. The resulting alkali hydroxide, the free weak bases or the salts are expediently by filtration or Wash away with water. It has been shown that you can get particularly cheap mechanical properties of the end products and not too short reaction times or achieved in the reaction with the polyisocyanates if you use the high molecular weight )> Dialcohols «as free as possible from alkali hydroxides and salts of weak acids, whose p-value is above 2 to 3.

Finally, a possible variation is described which is that the high molecular weight »dialcohols before their reaction with diisocyanates be fully or partially hydrogenated. As a result of the hydrogenation, the structurally different Polymers of one and the same diene, different hydrogenation products are possible. Is z. B. during the successive polymerization by adding or removing Solvents or by changing the temperature of the steric and structural If the course of the polymerization is changed, double bonds are obtained which are strong differ by their rate of hydrogenation. Is z. B. a difunctional Lithium compound first reacted with isoprene in the absence of ether and finally further isoprene added together with ether is obtained after the reaction with ethylene oxide or aldehydes and subsequent careful hydrogenation a "diol", which only has double bonds in the middle of the molecule like natural rubber, while after the ends, the double bonds formed by 1,2-addition have been hydrogenated are. Are these "diols" then reacted with diisocyanates and later with sulfur or vulcanized peroxides, this is probably because of the uniform spacing of the crosslinking points vulcanizates with excellent properties.

There is no protection at this point for the manufacture of the »dialcohols« claimed.

The implementation of high molecular weight »dialcohols« with polyisocyanates generally takes place under conditions similar to those of polyesters and polyethers with polyisocyanates. In particular, additives that are there to improve of properties can also be used here with good success.

So z. B. the known chain extenders or crosslinking agents, these are low molecular weight compounds with at least two active hydrogen atoms such as B. water, di- and higher-valent alcohols, di- and polyamines, at the same time or added afterwards. All procedures can also be followed which are used for the production of finished and semi-finished products, such as B.

Chain extension with diisocyanates, optionally with additives from chain extenders to crosslinkable rubber-elastic products, the later vulcanization with polyisocyanates, isocyanate releasers, sulfur or peroxides, are converted into crosslinked, insoluble elastic products, or production of foams by adding water or blowing agents or Production of homogeneous or porous moldings according to the Gief process, in which Extension and cross-linking take place in a single step with shaping, or coating of e.g. B. textile materials or bonds with mixtures Polyisocyanates and the high molecular weight »dialcohols«. Those in a solvent Process products produced can be extracted from this, if necessary still in a precipitation bath containing a crosslinking agent, spun into threads.

The known polyesters, polyethers and polyacetals can be used terminal hydroxyl groups are also used, with new substances with new valuable Properties arise. Such modified urea and / or urethane groups polymerization products containing are of great technical interest, e.g. B. as intermediate layers for connecting layers made from natural and synthetic rubbers consist, with layers of plastics, which after the isocyanate polyaddition process were produced because they are miscible with the rubbers before they cure and can be vulcanized with these common vulcanizing agents, on the other hand, however, are also compatible with the isocyanate-based elastomers and how these can be vulcanized with isocyanates. The proportion of polyester Polyethers and polyacetals can go so far that they exceed the proportion of high molecular weight in quantity "Dialkohole" exceeds. The modified products have compared to the known Polyurethanes have some advantages, such as B. better cold resistance, high hydrolysis resistance and elasticity and are easily vulcanizable with sulfur.

The process products differ in their structure and in their properties from all previously known by the isocyanate polyaddition process available. So they differ z. B. by the steric and structural Structure, due to the more uniform molecular weight, due to the lower degree of branching and in the case of block polymerization, through the regular structure of their units of the related polymerization products containing urethane groups, the are produced via free radical polymerization.

The new products, insofar as they are elastomers, stand out characterized by better tensile strength, high elongation at break and high elasticity, while the plastic materials have great impact resistance and a relatively high softening point own. They are used, for example, in the production of Tires, Seals, hoses, tubes, metal linings, straps, for shoe soles and - heels, as paint raw materials, for textile coating, as adhesives, for production of molded, pressed and injection molded articles.

Example Preparation of a difunctional organolithium compound as starting material To a suspension of 100 g of finely divided lithium in 61 1000 g of freshly distilled diethyl ether is added dropwise to anhydrous diethyl ether under the purest nitrogen 2,3-Dimethylbutadiene at 20 to 25 "C for one hour under vigorous Stir too. When heated, a mixture of the difunctional lithium compounds is formed of 2,3-dimethylbutadiene, its di- and oligomers. To complete the The reaction is stirred for a further 1 hour at 25 ° C. Then you do not press to remove the converted lithium from the yellow ethereal solution under the purest nitrogen and dilute the entire solution with anhydrous ether based on a normality of 1 on lithium. Yield about 10 to 121 solution.

1. Production of the high molecular weight bifunctional organometallic Connection and the “dialcoholate” Liquid butadiene is produced via piston metering pumps at a rate of 1000 cc / h and the above catalyst solution at 620 ccm / h is fed into an autoclave with vigorous stirring and brine cooling. As soon as the autoclave is filled, the needle valve is opened and that at an angle the top reaction tube is filled. The reaction mixture leaves the Autoclave with a temperature of 40 to 50 "C. After filling the reaction tube the high molecular weight difunctional lithium compound formed occurs practically free of monomers into the screw at a temperature of 10 to 15 "C. In the screw it becomes while cooling with water at 10 to 15 "C with a 2 molar solution of ethylene oxide in anhydrous ether at a speed of 370 ccm / h via a piston metering pump is pressed in, made to react. The ethereal solution of the formed)> dialcoholate " leaves the snail as a solid gelatinous mass.

2. Hydrolysis of the "dialcoholate" per gram atom of lithium is the Gelatinous mass mixed with about 20 to 30 ccm of water while cooling. Here The reaction material liquefies again, and the majority of it through hydrolysis The lithium hydroxide formed and the excess ethylene oxide are washed away with diluted sulfur acid and water removed. When the product is washed neutral is, it is on the water bath at atmospheric pressure later in a vacuum, by ether and frees water. The high molecular weight "dialcohol" formed has an OH number from 45 to 48 and is a light, thick oil.

3. Production of the polymer containing urethane groups 100 g of the dialcohol (molecular weight 2320) are first 1/1 hour with 0.80 ccm of water and 1 g of 2,6-di-tert-butyl-p-cresol is stirred at 40 to 50 "C.

Then, according to the invention, 15.5 g of an isomer mixture are stirred at 40 to 50 ° C from toluene-2,4- and toluene-2,6-diisocyanate, stirred at 500 ° C. for 2 hours and then heated in a closed vessel to 70 ° C and for 15 hours then 20 hours at 100 ° C. This gives a pale yellow, rubber-like product Material that can be processed excellently on cold and warm rollers.

The material is vulcanized with 3 to 6% dimeric toluene-2,4-diisocyanate or with an appropriate amount of 3,3'-dimethyl, 4,4-diisocyanatodiphenylurea mixed on the roller and pressed for 1/2 to 1 hour at 130 to 150 "C. Appropriate - is then reheated for a few hours at 100 ° C to vulcanize.

Claims (1)

The vulcanized product has a strength of 200 to 280 kg / cm2, an elongation at break of 400 to 500 ° / O and an elasticity of 45 to 58 ° / PATENT CLAIM: Process for the production of plastics including foams and sheet-like structures based on polyhydroxyl compounds, polyisocyanates and optionally crosslinking agents with shaping, characterized in that that polyhydroxyl compounds are used which are obtained by a) ionic polymerization olefinic monomers with alkali metals or bifunctional alkali metal organic Compounds to high molecular weight bifunctional organometallic compounds, b) Implementation of these high molecular weight organometallic compounds with alkylene oxides, Aldehydes or ketones to high molecular weight dialcoholates and c) hydrolysis of these to the free polyhydroxyl compounds have been obtained. Documents considered: German Auslegeschrift No. 1,060,594; British Patent No. 780 205.