DE2149896A1 - Polyurethane compound - Google Patents

Description

PATENT LAWYERS

DR. O. DITTMANN K. L. SCHIFF Df ,. A. ν. KÜNiSR DIPL. ING. F. STRBHL

β MUNICH OO MARIAHILFPLATZ 2 & 8

DA-4487

Description of the company's patent application

ASTERION LIMITED 54 Shepherd Road, Oakville ₉ Ontario, Canada

concerning
Polyurethane mass priority: October 9, 1970, Great Britain, No. 48,182 / 70

The invention relates to resin compositions based on polyurethanes and specifically relates to rigid hats which are suitable for numerous uses, such as casting _s embedding electrical parts, filling cracks and crevices, and in particular for potting purposes -

Polyurethanes have been further developed in the past two to three decades and have been used in a number of different ways Formulations for a wide variety of end uses formulated «For specific purposes, such as for the manufacture of rigid and elastomeric synthetic resin foams The relatively high price of the resin due to the special properties of these foamed products is not an obstacle to the industrial application. For applications in which dense, non-feuts products are required, however, poly-

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urethane is not widely used, mainly because many other types of resins, including various resins, which are much cheaper to manufacture, have fairly satisfactory properties. Even so, only a few exist resinous masses which can easily be hardened in situ from low viscosity starting materials and which are produced under ambient temperature conditions harden or solidify in a relatively short period of time, for example within a few minutes. This rapid solidification under ambient temperature conditions

is particularly valuable for grouting purposes, such as when machines are to be fastened to a concrete floor using bolts embedded in the concrete. Other uses where these properties can be valuable include fixing healers or posts in concrete or in a rocky environment if the product is to be used at low temperatures, or if the compound is to penetrate into fine cracks or is used for embedding electrical parts. The use of these low viscosity materials also helps create an intimate bond between the resin composition and the substrate to which it is applied. A low viscosity is also important for embedding, but a somewhat slower hardening compound is required in order to carry out the Vaka ^; ; i allow sntlüfteiis au.

It is known j various types of polyurethanes by reacting a variety of polyols with an organic poly-

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to produce functional isocyanate. Two procedures commonly used are the so-called “prepolymer ¹¹ ” or “prepolymer” or the “semi-prepolymer” method and the so-called one-shot method.

In the prepolymer or semi-prepolymer process a polyol, usually of the polyether or polyester type, first with an isocyanate in an amount in excess of that required to react with the hydroxyl groups implemented. In this way, a prepolymer is formed which is accessible for the further reaction with hydroxyl groups Contains isocyanate groups. Highly crosslinked products can be produced by suitable choice of materials. That However, the semi-prepolymer process necessarily involves more process steps than the one-step process, and it cannot a low viscosity of the prepolymer can thus easily be achieved.

The "one-shot" or one-step process is a polyfunctional one Isocyanate reacted with a polyol and the final polyurethane quickly by reacting the two components educated. A high degree of crosslinking can be achieved by using relatively low molecular weight polyols, the three or have more hydroxyl groups per molecule. The response rates vary depending on the structure of the reactants and in many cases are catalysts such as tertiary amines or organic Tin compounds, required. More than one type of polyol is usually used. The properties of the resulting product vary between elastomeric and rigid.

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Although, as can be seen from the discussion above, rigid Polyurethane compounds can be produced by the one-step process, the price of the product is too high to be economical To enable use for many different purposes.

In general, a crosslinking agent of the type mentioned, when used on its own with the isocyanate, a product too brittle for practical purposes. Furthermore the reaction rate can be so high that the thermal. Decomposition of the resulting product causes Vvird. Usually therefore, more than one type of polyol is employed, including at least one slightly higher molecular weight polyol as the crosslinking agent to form a resin with greater toughness. However, these products are still expensive.

Fillers are difficult to incorporate satisfactorily in an amount that would make the product v / it cheaper because they interfere with the thorough mixing of the reactants that is required is to achieve a practically homogeneous product. Attempts have been made to create different types of extenders too use such as coal tar and bituminous products. These endeavors however, were either directed to the manufacture of a material called modified tars can, for example, for use as road surfaces, or products have been made thereby, which even if they are rigid did not have the hardness and strength required for many uses, such as many the mentioned potting purposes. In most of these attempts the prepolymer or semi-prepolymer method was used -, -

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det. *

The invention is based on the discovery that by careful selection of the polyol, compatibility with "certain solvent or oil compositions can be achieved and a highly crosslinked rigid polyurethane composition of high strength can be formed. The novel polyurethane composition of the present invention is rigid and substantial homogeneous product obtained by reacting in a single stage a polyfunctional isocyanate with an aliphatic polyol which has 4 to 5 hydroxyl groups and an average value of not more than 1.5 ether linkages per reactive hydroxyl group, the isocyanate and the Polyol present at the beginning of the reaction in a homogeneous positive phase mixture with an extender, which consists of a hydrocarbon with aromatic character together with an aliphatic and / or naphthenic hydrocarbon, in which each of the hydrocarbons does not ^{boil below 110 0} C, and a weight ratio v on total hydrocarbons to reactants in the range of 0.1: 1 to 1: 1 is adhered to.

A substantially homogeneous product is to be understood as meaning a product that is visible to the naked eye or itself appears more or less homogeneous under eighty times magnification, taking into account the filler particles that may also be present. Under the feature that the isocyanate and the polyol at the start of the reaction in a homogeneous liquid phase mixture to be present with the hydrocarbon, it is understood that mutual solubility at least in the applied Proportions between the isocyanate and the polyol

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on the one hand and the hydrocarbon on the other hand ".

The polyol used according to the invention preferably contains at least one tertiary nitrogen atom, since compounds containing tertiary nitrogen atoms appear to be more compatible with the hydrocarbon and have the advantage of exerting a catalytic effect on the reaction. According to another embodiment, according to which a separate catalyst is used, various other polyols of the specified type can be used, for example tetraols based on pentaerythritol, such as compounds of the Wyandotte PeP series, some compounds of the Atlas G series based on sorbitol and compounds of the Dow RS series sucrose-based. I ¹ Ur many applications it is also preferable that the polyol having a relatively crowded molecular structure because thereby a high degree of crosslinking is caused in the product, to produce products with high strength and In particular, it has been found that the reaction products of ethanollarain, ethylene diamine or diethylenetriamine with an alkylene oxide, particularly propylene oxide, obtained using one to two moles of the alkylene oxide for each reactive hydrogen atom, are particularly satisfactory polyols for the purposes of the invention . Specially preferred The reaction product of ethylenediamine with four moles of propylene oxide, which is referred to as IT, N, N 'IT' -Tetrakis (2-hyctroxypropyl) ethylenediamine, and similar products, made from ethylenediamine and up to eight parts of propylene oxide, are ugly. These products have four hydroxyl groups in a relatively compact molecular structure; this number of hydroxyl groups is preferred in the polyols.

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It is therefore generally "preferred" to use a poly oil of the following to use the structure:

HO-R ¹ E ¹ - OH

HO - R ¹ R ¹ - OH

in which R and R ^{1 represent} lower alkylene or lower oxalkylene groups. Preferred among these compounds are products in which R ^{1 is} the -CH ₂ .CH (CH ₅ ) group or the -CH ₂ -CH (CH ₅ ) .0.CH ₂ . CH (CH-Z) group means, and compounds in which R is the -Clip.CHp group. It is possible to use mixtures of polyols which meet the stated conditions, and it is also possible to use a polyol with the specified characteristics together with a minor proportion of another hydrogen. Substance-containing compound, such as a diol, triol, amine or amino alcohol to use as modifiers to achieve desired properties, for example an increased reaction rate, increased toughness or flexibility or increased elongation. For example, the addition of a nitrogen-free polyol without an additional catalyst tends to increase the pot life and cure time, and the addition of a triol or a tetraol or pentavalent alcohol tends to produce less hard, but often tougher cured products. Non-reactive, for example sterically hindered, hydroxyl groups have little effect.

The polyfunctional isocyanate must have at least two isocyanate groups per molecule and it is preferred to use a di-

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or to use triisocyanate or a crude product in which the average number of isocyanate groups per molecule has any value between two and three. Typical of the isocyanates that can be used are aromatic isocyanates such as distilled or crude tolylene diisocyanate, commonly referred to in the trade as TDI ", xylylene W.tJ'-diisocyanate, known commercially as XDI", diphenylmethylene diisocyanate, "especially the predominant one of the p, p ^f isomeric product, which is also known as methylene bisphenyl diisocyanate or MDI ", especially in crude or undistilled form, and the polyary! polyisocyanates, which consist of an average of between two and three phenyl groups separated by methylene groups are separated, with each phenyl ring carrying an isocyanate group, for example a product sold in crude or undistilled form under the trade name PAPI. Typically, MDI has a functionality of about 2.0 and PAPI has a functionality of about 2.3 * I ¹ D) I is a particularly satisfactory isocyanate for purposes of the invention. Aliphatic isocyanates are generally more expensive, but can be used for special purposes, especially when light stability is important, such as for coating compositions. Examples of such aliphatic isocyanates are hexamethylene diisocyanate and 4,4'-methylenebis (cyclohexyl isocyanate).

The first hydrocarbon used in the present invention must, as already indicated, have essentially aromatic character. This includes all real aromatic hydrocarbons. A suitable test for the aromatic character is the so-called clay test (ASTM D 2007); those in this description

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The values given for the aromatic character were determined by this test. Thus, a hydrocarbon with essentially aromatic character is understood to mean a hydrocarbon which has at least 50 ^c / o aromaticity, although it is preferred that the hydrocarbon show at least 75% aromaticity. particularly preferred are "hydrocarbons naphthalenes, indanes and tetralins and benzene hydrocarbons are mixtures containing, and which have about 80 bis 90 ° / o aromaticity. Benzene is not used for the purposes of the invention because it is too volatile. The aromatic hydrocarbons must be liquid and miscible with the reactants. Particularly preferred are hydrocarbons which are essentially aromatic in character and which are freely miscible with each of the reactants, namely with the polyol and with the isocyanate. Aromatic hydrocarbons such as toluene and xylene are suitable for the purposes of the invention and are in fact capable of being used in the manufacture of hardened products which are rigid pesticides with considerable hardness and pestiness and in which the odor of the hydrocarbons is not apparent. Hydrocarbons containing both aromatic rings and aliphatic side chains can also be used in many cases; However, if the aromatic character is not sufficiently pronounced, the compatibility with the starting materials may be inadequate. In any given pail, a simple test can be used to determine whether the hydrocarbon is miscible with the starting materials in the proportions to be used. If this feature is present, the hydrocarbon also often turns out to be with the hardened sample finally obtained.

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product as tolerable, i.e. that the odor of the hydrocarbon is generally not noticeable in this cured product and that the cured product is dry to the touch and shows no tendency to exude hydrocarbons at ordinary room temperature. Preferred hydrocarbons are due to its cheapness and ease of access it is determined by Products obtainable from cracking petroleum fractions, especially products that are known in the art as aromatic concentrates High temperature cracking processes are referred to. These concentrates have heretofore been seen as undesirable by-products of cracking processes considered and are therefore available at a low price. Two of these currently available products are supplied by the manufacturer (Esso Chemical Canada) designated as an aromatic concentrate and CPC 2019 A. Both materials are products that are used in a steam cracking plant can be obtained.

The two materials show the following typical characteristics:

Aromatic Concentrate CPC - 2019 A

85

10 «5 »

Aromatics 85 volume% saturated compounds 15 " Olefins - Asphaltenes 18 wt. $ sulfur 2 " Density, ⁰ API -4 Viscosity at 99 ° n_ rtts 100-200

13.6-15.4 32-33

Distillation according to ASTM D 1160, corrected for boiling on 760 mm start: 260-288 "c

Bp, AOfo: 357-385 ° C

Kp, 70 / o: 443-482 ⁰ C.

D-86 boil

start: 185-1 96 ° C bp, 50 $: 229-249 C end of boiling : 29O, 6-31Oc

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The main components of the aromatic concentrate are naphthalenes, Indanes, tetralines and alkylbenzenes. The aromatic concentrate leads to mixtures with the starting material that are suitable for some uses are somewhat viscous; aie in this regard preferred blends were therefore prepared using blends of the aromatic concentrate and CPC 201S A, with preferred the latter product was not present in excess and in particular a mixture in the ratio 1: 1 was used. The ax'oiüatic concentrate can optionally be diluted with other liquid hydrocarbons of aromatic character but of low viscosity can be used, such as xylene. the Use of aromatic concentrate or a similar relatively high-boiling material by itself or in the described Sometimes diluted is very preferred because it produces products with extremely good physical properties can be. There seems to be some evidence that higher molecular weight extenders are preferred are.

The second hydrocarbon used in the present invention is an aliphatic or naphthenic hydrocarbon, which is preferably saturated. Viie in Pall of the aromatic hydrocarbon are excluded compounds having a low boiling point of less than about 11O ⁰ C because of their volatility. However, such hydrocarbons are usually available in the form of mixtures of several different components and are usually characterized by their origin and boiling range. The following hydrocarbons can therefore be used for the purposes of the invention: Petroleum naphthas

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or - "benzine, of .not less than 10 $ below 175 C and not less $ 95, typically have a Siedebereieh than as below 240 ⁰ C (ASTM D 86) such as VM & P naphtha, the largely of naphthenes and paraffins "is and typically has a boiling range of 119 ° - having 143 ° C, high flash naphtha having a boiling range of about 150-200 ⁰ C, kerosene having a boiling range of about 150 - 30O ⁰ C, various fuel oils, such as fuel oil Ur. 1 with .einem boiling range of about 200 ° -. 33O ⁰ C and # 2, which is somewhat less volatile, Bunker C oil, and mineral oils with even higher boiling range.

Many of these products, especially those used as fuels, have an extremely variable composition and can be used alongside Paraffins and / or naphthenes contain varying amounts of aromatic hydrocarbons. One such aromatic containing hydrocarbon therefore not only supplements the first hydrocarbon but also replaces it in one greater or lesser extent, depending on the aromatic content. Since the quantitative ratio used according to the invention of the first hydrocarbon to the second hydrocarbon is of importance, it is obviously preferred To use hydrocarbons with a relatively constant composition from batch to batch. It is also used for many purposes preferably the use of hydrocarbons too high viscosity avoided. Therefore, if the chosen is the first hydrocarbon aromatic concentrate, which is present on its own or in a mixture with CPC 2019 A, it is preferred uses a relatively poorly viscous second hydrocarbon, such as that under the designation Acme 34 from Gulf Oil

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Canada Limited or the one under the name Diol 34 from Imperial Hydrocarbon available from Oil Limited. Both oils are high naphthenic oils with low vapor pressure and are quite throaty constant composition; in addition, "they have low viscosity. On the other hand, when a low viscosity of the mixtures of hydrocarbon and reactants is not so important or when the aromatic hydrocarbon chosen is not very viscous, a heavier second hydrocarbon can be used, like Bunker G-Oil. As "stated earlier," however, has the latter Material has a very variable composition, so it may be necessary to test samples from each batch of the oil infer that the fully satisfactory for a specific application Ratios of total hydrocarbon to reactants and first hydrocarbon to second hydrocarbon can be determined. In any particular case, a simple test will indicate whether the hydrocarbon is involved with the starting materials is miscible in the proportions in which it is to be used. If this characteristic is present, so the hydrocarbon generally proves to be miscible with the hardened end product, i.e. the smell of the Hydrocarbon in this cured product is generally not noticeable and the cured product is felt dry to the touch and does not tend to exude hydrocarbon under normal ambient temperature conditions.

The ratio of the first hydrocarbon to the second hydrocarbon present according to the invention can vary from about 5.1 to 1: 1, ie about 15 to 50 % of the total hydrocarbon can be aliphatic and / or naphthenic. At . .

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a proportion below about 15 ^ is compared with a small improvement the use of aromatic hydrocarbon alone achieved, which is the subject of German patent application P ......... The exact! Puncture of the second hydrocarbon is not known, but it seems the compatibility of the hydrocarbon to modify with the reactant, i.e., it forms a mixture with the first hydrocarbon, which is something is less compatible with the intermediates and / or end products of the reaction. Surprisingly, this results in products with higher compressive strength than by using aromatic hydrocarbon alone.

The mixed hydrocarbon used as extenders can according to the invention in amounts Ms to 50 wt. ^ ₅ based on the total weight of hydrocarbon and reactants, and depending on the precise choice of the reactants and Kohlenwasserstof it f, is added. However, when a hydrocarbon mixture is used with less pronounced aromatic character, then the upper limit of the hydrocarbon content slightly lower than this his fourth, "for example, $ 45 · For practical purposes, is achieved only a small advantage if less than 9 to 10 io of total hydrocarbon are added, and a * preferred minimum content is 30 wt. $. particularly preferred ratios are iia range of about 40 to 50 $ fo to Gesaratkohlenwasserstoffen, particularly at about $ 45.

One of the significant advantages of the products according to the invention is that the use of hydrocarbons with moderate viscosity as an extender and the addition of fillers

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substances made possible. These fillers can be "any fillers be commonly used in plastics engineering will. For "certain applications, such as casting compounds, finely divided mineral fillers such as kie * acidic acid, preferred. For example, hardened products with high compressive strength and extremely high modulus can be produced be, the 50 wt.? € of a finely divided silica contain, such as silica powder or other forms of silica like sand. Thixotropic (uncured) masses can be made using colloidal silica, for example will.

Another advantage of using the hydrocarbons as extenders is the fact that their addition reduces the Production of polyurethane compositions with considerable toughness enabled (i.e. with reduced brittleness, not with increased elastomeric nature), so that these extenders have the function of the additional Polyols can meet. Finally, adding the hydrocarbon extender slows the reaction down and thereby reduces the exothermic heat.

The invention is further illustrated by the following examples. The compressive strengths and moduli were measured by modifying the method used to test concrete will.

Example A.

This example is given for comparison with Examples 4 to 6 below for the effect of adding different types

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and to show the proportions of the second hydrocarbon.

Two components were made in the following way:

Component A: 36 parts by weight of raw MDI 14 parts by weight of extender

Component B: 19 parts by weight Quadrol 31 parts by weight extender

The two components were simply mixed together, whereupon the reaction started and progressed to the solidification point within a few minutes. The hard product was tested a few hours later. It exhibited the following properties: compressive strength: 429 kg / cm (6100 psi), compression modulus: 13,991 kg / cm ² (199,000 psi). The extender consisted of equal parts by weight of aromatic concentrate and CPC 2019 A. Quadrol is the trademark for. N, N, N ¹ , IP-tetrakis (2-hydroxypropyl) ethylenediamine.

The examples according to the invention given below were carried out in the same way as Example A.

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total
Amount of
Extenders, - 17 - "" CPC ^ 2019A Acme 3 ^
ίο 21 43896 Compression
module,
kg / cm
(psi) example 35 25th 25th physical own
societies 22,357
(318,000) 1 40 Type of extender 25th 25th pressure
firm
ability 2
kg / cm,
(psi) 18,490
(263,000) 2 45 Aroma
table
Conc
kicked, % 25th 25th 822.6
(11,700) 16,451
(234,000) 3 45 50 40 20th 674.9
- (9,600) 14-342
(204,000) 4th 45 50 35 50 569.5
(8,100) 14,694
(209-000) 5 45 50 30th 40 513.2
(7,300) 14,485
(206,000) 6th 45 40 0 50 513.2
(7,300) 14,542
(204,000) 7th 45 35 0 40 506.2
(7,200) 8th 45 30th 0 50 562.5
(8,000) 9 .70 60 513.2
(7-300) 50

M game 10

Example 5 was repeated except that SAE 10 lubricating oil was used in place of Acme 34. The compressive strength was 548.4 kg / cm ² (7 x 800 psi) and the compression modulus was 15,526 kg / cm ² (218,000 psi).

Example 11

Example 5 was repeated, except that petrol (mineral spirit) was used instead of Acme 54. The compressive strength achieved was 520.5 kg / cm ² (7-400 psi) and the compression modulus was 14-061 kg / cm ² (200,000 psi).

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The gasoline used had a Kauri-butanol value of 38, an aniline point of 54 ° G and the following values of the ASTM distillation: Initial boiling point: 157 ⁰ C (3U ⁰ * ^1); End point: 195 ⁰ C (3f - 3 ° F)

Example 12

Example 3 was repeated, but instead of Acme 34 Rubber Extender Oil A (Gulf Oil Canada Ltd.) was used «The

The compressive strength achieved was 548.4 kg / cm, the compression modulus 15,748 kg / cm ² (224,000 psi).

Example 13

Example 3 was repeated, but Rubber Extender Oil B (Gulf Oil Canada Ltd.) was used in place of Acme 34. The compressive strength was 555.4 kg / cm ² (7 * 900 psi), the compression modulus was 15,045 kg / cm ² (214,000 psi).

Example 14

Example 4 was repeated, but petrolatum (white mineral oil) was used instead of Acme 34. The compressive strength was 527 kg / cm (7-500 psi) and the compression modulus was 14,483 kg / cm ² (206,000 psi).

Example 15

Example 4 was repeated; however, it was replaced by Bunker C-Oil

used by Acme 34. The compressive strength was 541.4 kg / ce (7,700 psi), the compression modulus 14,694 kg / cm (209,000 psi).

Example 16

Example 9 was repeated using SAE 10 lubricating oil in place of Acme 34. The compressive strength achieved was:

ρ O

548.4 kg / cm (7,800 psi), the compression modulus 15 * 326 kg / cm (218,000 psi). -19_

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Example 17

Example 9 was repeated using mineral spirits in place of Acme 34. The compressive strength was 520.3 kg / cm (7 * 400 psi) and the compression modulus was 14,061 kg / cm ² (200,000 psi).

The gasoline had a Kauri-butanol value of 38, an aniline point of 54 ⁰ C and showed the following values of the ASTM distillation: 'Initial boiling point 157 ⁰ C, 195 ° C endpoint.

Example 18 .

Example 9 was repeated; after Rüther Extender Oil A (Gulf Oil Canada Ltd.) used in place of Acme 34. Which he-

Targeted Compressive Strength "was 548.4 kg / cm _} the compression modulus was 15-748 kg / cm ² (224,000 psi).

Example 19

Example 9 was repeated using after Ruhher Extender Oil B (Gulf Oil Canada Ltd.) instead of Acme 34. The printing

strength "was 555» 4 kg / cm (7 x 9ΟΟ psi), the compression modulus was 15-045 kg / cm ² (214,000 psi).

Example 20

Example 10 was repeated using after petrolatum (white mineral oil) instead of Acme 34. The compressive strength was 527.3 kg / cm ² (7-500 psi) and the compression modulus was 14,483 kg / cm ² (206,000 psi).

Example 21

Example 10 was repeated, but Bunker C-OI was used instead Acme 34 clay used. The compressive strength was 541.4 kg / cm (7-700 psi) and the compression modulus was 14,694 kg / cm (209,000 psi).

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Example 22

EDP 500 * 27 parts by weight

PAPI 28 parts by weight

Extender ** 45 parts by weight

* An amine-based polyol that is likely a propylene oxide adduct of ethylenediamine represents. Functionality: 4 · Average molecular weight: 495 · Hydroxyl number, KOH / g: 450.

** The extender "consists of a mixture of aromatic concentrate, CPC 2019 A and Acme 34 at a ratio of 50:25:25 The three ingredients were mixed thoroughly, whereupon curing occurred rapidly and a rigid product was formed which had the following properties:

Tensile strength 174.3 kg / cm ² (2,480 psi)

Pulling eye 9.540 kg / cm ² (135-700 psi) elongation $ 20

Compressive Strength 225.0 kg / cm ² (3,200 psi)

Compression modulus 8,310 kg / cm ² (118,200 psi)

Patent claims:

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Claims (15)

Patent claims 1. Polyurethane composition, characterized in that it contains the rigid, substantially homogeneous reaction product 'of an aliphatic polyol with 4 Ms 5 hydroxyl groups and an average of no more than 1.5 ether linkages per reactive hydroxyl group, and a polyisocyanate and as an extender a hydrocarbon mixture that consists of a hydrocarbon having aromatic character and an aliphatic and / or naphthenisehen hydrocarbon in a ratio of hydrocarbon having aromatic character to aliphatic and / or naphthenic hydrocarbon in the range of 5: 1 "to 1: 1", wherein none of the hydrocarbons below 110 ⁰ C. boils and the weight ratio of total hydrocarbon to reactants for the polyurethane is in the range 1:10 to 1: 1. 2. Polyurethane composition according to claim 1, characterized in that it is the product of the single-stage conversion of the aliphatic Polyol and the polyisocyanate represents "in which these reactants at the beginning of the reaction in a homogeneous liquid phase "in admixture with the hydrocarbon extender in a weight ratio of total hydrocarbon extenders to reactants are in the range of 1:10 to 1: 1 and a weight ratio from hydrocarbon with aromatic character to aliphatic and / or naphthenic hydrocarbon in the range of 5: 1 to 1: 1 is adhered to. 3 · Polyurethane mass according to claim 1 or 2, characterized in that that the poly oil has at least one tertiary nitrogen atom contains. ■ -22 · 209816/1583. 2H9896 4. Polyurethane composition according to claim 1 to 3, characterized in that the poly oil contains 4 hydroxyl groups. 5 · Polyurethane mass according to claim 1 Ms 4, characterized net that the polyol has the formula HO-R ¹ R ^f -OH N-R-N HO-R ¹ R ¹ - OH in which R and R ^{1 are} lower alkylene or lower oxalkylene groups. 6. Polyurethane composition according to claim 5, characterized in that R and R ¹ stand for lower alkylene radicals. 7 «Polyurethane composition according to claim 5, characterized in that R is a lower alkylene and R ^{1 is} a lower oxalkylene radical. 8. Polyurethane composition according to claim 5, characterized in that R 'is a -CH ₂ -CH (CH ₅ ) group, or a -CH ^ CH (CH ₅ ) .0.CH ₂ -CH (CH,) - group . 9. Polyurethane composition according to claim 5 to 8, characterized in that that R is an ethylene group. 10. PolyuiEthane mass according to claim 1 to 9, characterized in that that the polyisocyanate is an aromatic di- or triisocyanate. 11. Polyurethane composition according to claim 10, characterized in that the polyisocyanate is toluene diisocyanate, diphenylmethane diisocyanate, in particular diphenylmethane-p.p'-diisocyanate, or a -23- 20981 6/1583 Is polyaryl polyisocyanate. 12. Polyurethane composition according to claim 1 to 11, characterized in that -that the polyisocyanate is a compound of the formula NCO ITCO / ¹ CH, NCO η in which η has an average value of 1. 13. Polyurethaninasse according to claim 1 to 12, daäureh characterized, that as a hydrocarbon with aromatic character it is an aromatic concentrate from a high-temperature cracking process contains. 14. Polyurethane composition according to claim 1 to 13 »characterized in that that the weight ratio of hydrocarbon to reactants for the polyurethane is in the range of 2: 3 "to 1: 1, 15. Polyurethane composition according to claim 1 to 14, characterized in that that it also contains a hill substance, especially finely divided Contains silica. Process for producing a rigid, substantially homogeneous Polyurethane composition by reacting an aliphatic polyol with a polyisocyanate, characterized in that a polyisocyanate with an aliphatic polyol with 4 to 5 hydroxyl groups and on average not in one stage more than 1.5 ether linkages per reactive hydroxyl group reacts in the presence of a hydrocarbon mixture that -24- 209816/1583 See a hydrocarbon with aromatic character together with an aliphatic and / or naphthenic hydrocarbon in a weight ratio of hydrocarbon with aromatic character to aliphatic and / or naphthenic hydrocarbon in the range of 5: 1 Ms 1: 1, with none of the carbons boiling below 110 ⁰ C and the PoIyisocyanat and Polyoil beginning of the reaction in a homogeneous liquid mixture with the hydrocarbons present, and wherein a weight ratio of total reactants to hydrocarbon in the range of 1:10 to 1: 1 is maintained. 209816/1583