DE102004041605A1 - New carbodiimide compounds useful in the preparation of polyurethane and as stabilizers against hydrolytic dismantling of ester containing compounds e.g. polyaddition- and polycondensation products - Google Patents

Abstract

Carbodiimide compounds (I) (where the content of 1-methyl-2,5-dihydro-phospholene-1-oxide (a) and 1-methyl-2,3-dihydro phospholene-1-oxide (b) is less than 100 ppm) are new. Carbodiimide compounds of formula (I) (where the content of 1-methyl-2,5-dihydro-phospholene-1-oxide (a) and 1-methyl-2,3-dihydro phospholene-1-oxide (b) is less than 100 ppm) are new. n : 1-20; R1, R2optionally substituted (cyclo)aliphatic, araliphatic or aromatic compounds; and R3, R4H, -CH3 or -CH2-CH3. Independent claims are also included for: (1) the preparation of (I); and (2) polyurethane containing (I) obtained by the method. [Image].

Description

mit den folgenden Bedeutungen für n, R₁, R₂, R₃ und R₄:
n: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 13, 14, 15, 16, 17, 18, 19 oder 20,
R₁: aliphatischer, cycloaliphatischer, araliphatischer oder aromatischer, gegebenenfalls substituierter gegebenenfalls verzweigtkettiger Rest, bevorzugt -CH₂-CH₂-, -CH₂-CH₂-CH₂- oder -CH₂-CH₂-CH₂-CH₂-,
R₂: aliphatischer, cycloaliphatischer, araliphatischer oder aromatischer, gegebenenfalls substituierter gegebenenfalls verzweigtkettiger Rest, bevorzugt -CH₂-CH₂-, -CH₂-CH₂-CH₂- oder -CH₂-CH₂-CH₂-CH₂-,
R₃: H, -CH₃ oder -CH₂-CH₃, bevorzugt -H oder -CH₃, besonders bevorzugt -H,
R₄: H, -CH₃ oder -CH₂-CH₃, bevorzugt -H oder -CH₃, besonders bevorzugt -H,
wobei der Gehalt an 1-Methyl-2,5-dihydro-phospholen-1-oxide und 1-Methyl-2,3-dihydro-phospholen-1-oxide, d.h. der Gesamtgehalt an den beiden Katalysatoren 1-Methyl-2,5-dihydro-phospholen-1-oxide und 1-Methyl-2,3-dihydro-phospholen-1-oxide, kleiner 100 ppm, bevorzugt kleiner 50 ppm, besonders bevorzugt kleiner 25 ppm, insbesondere kleiner 10 ppm ist, bezogen auf das Gewicht des Carbodiimids (i). Außerdem betrifft die Erfindung Verfahren zur Herstellung von

mit den folgenden Bedeutungen für n, R₁, R₂, R₃ und R₄:
n: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 13, 14, 15, 16, 17, 18, 19 oder 20,
R₁: aliphatischer, cycloaliphatischer, araliphatischer oder aromatischer, gegebenenfalls substituierter gegebenenfalls verzweigtkettiger Rest, bevorzugt -CH₂-CH₂-, -CH₂-CH₂-CH₂- oder -CH₂-CH₂-CH₂-CH₂-,
R₂: aliphatischer, cycloaliphatischer, araliphatischer oder aromatischer, gegebenenfalls substituierter gegebenenfalls verzweigtkettiger Rest, bevorzugt -CH₂-CH₂-, -CH₂-CH₂-CH₂- oder -CH₂-CH₂-CH₂-CH₂-,
R₃: H, -CH₃ oder -CH₂-CH₃, bevorzugt -H oder -CH₃, besonders bevorzugt -H,
R₄: H, -CH₃ oder -CH₂-CH₃, bevorzugt -H oder -CH₃, besonders bevorzugt -H, wobei man 1,3-Bis-(1-methyl-1-isocyanato-ethyl)-benzol in Gegenwart von

1-Methyl-2,5-dihydro-phospholen-1-oxide (CAS [930-38-1]) und/oder

1-Methyl-2,3-dihydro-phospholen-1-oxide (CAS [872-45-7]) zum Carbodiimid umsetzt und 1-Methyl-2,5-dihydro-phospholen-1-oxide und/oder 1-Methyl-2,3-dihydrophospholen-1-oxide aus dem Carbodiimid entfernt, bis der Gehalt an 1-Methyl-2,5-dihydro-phospholen-1-oxide und 1-Methyl-2,3-dihydro-phospholen-1-oxide kleiner als 100 ppm, bevorzugt kleiner 50 ppm, besonders bevorzugt kleiner 25 ppm, insbesondere kleiner 10 ppm ist, bezogen auf das Gewicht des Carbodiimids (i). Des weiteren betrifft die Erfindung Polyurethane enthaltend die erfindungsgemäßen Carbodiimide.The invention relates to carbodiimide (i) having the following structure:

with the following meanings for n, R ₁ , R ₂ , R ₃ and R ₄ :
n: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 13, 14, 15, 16, 17, 18, 19 or 20,
R ₁ : aliphatic, cycloaliphatic, araliphatic or aromatic, optionally substituted, optionally branched-chain radical, preferably -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ - or -CH ₂ -CH ₂ -CH ₂ -CH ₂ - .
R ₂ : aliphatic, cycloaliphatic, araliphatic or aromatic, optionally substituted, optionally branched-chain radical, preferably -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ - or -CH ₂ -CH ₂ -CH ₂ -CH ₂ - .
R _{3 is} H, -CH ₃ or -CH ₂ -CH ₃ , preferably -H or -CH ₃ , more preferably -H,
R _{4 is} H, -CH ₃ or -CH ₂ -CH ₃ , preferably -H or -CH ₃ , more preferably -H,
wherein the content of 1-methyl-2,5-dihydro-phospholene-1-oxides and 1-methyl-2,3-dihydro-phospholene-1-oxides, ie, the total content of the two catalysts 1-methyl-2.5 dihydro-phospholene-1-oxides and 1-methyl-2,3-dihydro-phospholene-1-oxides, less than 100 ppm, preferably less than 50 ppm, more preferably less than 25 ppm, in particular less than 10 ppm, by weight of carbodiimide (i). Moreover, the invention relates to methods for the production of

with the following meanings for n, R ₁ , R ₂ , R ₃ and R ₄ :
n: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 13, 14, 15, 16, 17, 18, 19 or 20,
R ₁ : aliphatic, cycloaliphatic, araliphatic or aromatic, optionally substituted, optionally branched-chain radical, preferably -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ - or -CH ₂ -CH ₂ -CH ₂ -CH ₂ - .
R ₂ : aliphatic, cycloaliphatic, araliphatic or aromatic, optionally substituted, optionally branched-chain radical, preferably -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ - or -CH ₂ -CH ₂ -CH ₂ -CH ₂ - .
R _{3 is} H, -CH ₃ or -CH ₂ -CH ₃ , preferably -H or -CH ₃ , more preferably -H,
R _{4 is} H, -CH ₃ or -CH ₂ -CH ₃ , preferably -H or -CH ₃ , more preferably -H, where 1,3-bis (1-methyl-1-isocyanatoethyl) benzene in the presence of

1-methyl-2,5-dihydro-phospholene-1-oxides (CAS [930-38-1]) and / or

1-methyl-2,3-dihydro-phospholene-1-oxides (CAS [872-45-7]) to give carbodiimide and 1-methyl-2,5-dihydro-phospholene-1-oxides and / or 1-methyl -2,3-dihydrophospholen-1-oxides removed from the carbodiimide until the content of 1-methyl-2,5-dihydro-phospholene-1-oxides and 1-methyl-2,3-dihydro-phospholene-1-oxides less than 100 ppm, preferably less than 50 ppm, more preferably less than 25 ppm, in particular less than 10 ppm, based on the weight of the carbodiimide (i). Furthermore, the invention relates to polyurethanes containing the carbodiimides according to the invention.

organic Carbodiimides are known and are used, for example, as Stabilizer against the hydrolytic degradation of ester groups Compounds, for example polyaddition and polycondensation such as. Polyurethanes. Carbodiimides may be well known Process be prepared, for example by the action of basic catalysts on mono- or polyisocyanates with elimination of carbon dioxide. Suitable catalysts are e.g. heterocyclic, phosphorus bound containing compounds, metal carbonyls, phospholines, phospholens and phospholidines and their oxides and sulfides.

such Carbodiimides, their preparation and their use as stabilizers against the hydrolytic cleavage of polyester-based plastics are used e.g. described in EP-A 808 828, DE-A 4 318 979, DE-A 4 442,724 and EP-A 460 481.

The The object of the present invention was improved carbodiimides as stabilizers against the hydrolytic cleavage of plastics based on polyester to develop the optimal incorporation in the starting components of the plastics or in the plastics themselves and also the dynamic and static properties the plastics, in particular polyurethane elastomers, not adversely affect. A special goal was the Property profile of the plastics to be stabilized, in particular of the thermoplastic polyurethane also under conditions in which usually Hydrolysis occurs to get. In particular, the tensile strength should and / or the elongation at break in particular a thermoplastic polyurethane even with prolonged storage under moist Conditions are improved.

These Task could by the carbodiimides, which are obtainable by the method described above, and in particular the polyurethanes containing the carbodiimides according to the invention are dissolved.

Purely statistically, the hydrolytic degradation of a polyester a molecule by splitting two molecules. This is accompanied by a corresponding molar mass loss. at Use of the carbodiimide occurs by trapping the acidic Polymer residue to a combination of these two molecules. The Problem of molecular weight reduction, however, is not solved. The particular advantage of the carbodiimides of the invention is both in their outstanding effectiveness as hydrolysis stabilizers as well as in their ability to talk about the Acrylate group at the end of the carbodiimide crosslinks and thus higher molecular weights build up in the polymer. This particular advantage comes in particular in thermoplastics, preferably thermoplastic polyurethane particularly advantageous for carrying.

• • Leicht herstellbar
• • Ohne Nebenreaktionen in TPU einarbeitbar
• • Niedrige Viskositäten bei Verarbeitungstemperatur (60°C)
• • pumpfähig bei Raumtemperatur
• • Lagerstabil
• • Wirksam als Hydrolyseschutzmittel, insbesondere wenn katalysatorfrei, d.h. mit deutlich reduziertem Gehalt z.B. an Phospholen-oxid
• • Geringe Flüchtigkeit
• • Kostengünstig
• • Reaktion in Masse, d.h. ohne Lösungsmittel

In addition, the carbodiimides according to the invention have the following advantages:

• • Easy to produce
• • Can be used without side reactions in TPU
• • Low viscosities at processing temperature (60 ° C)
• • pumpable at room temperature
• • Shelf life
• • Effective as a hydrolysis protection agent, especially when catalyst-free, ie with significantly reduced content, for example, of phosphole oxide
• • Low volatility
• • Cost effective
• • Reaction in bulk, ie without solvent

umgesetzt wird mit den folgenden Bedeutungen für R₁ und R₃:
R₁: aliphatischer, cycloaliphatischer, araliphatischer oder aromatischer, gegebenenfalls substituierter gegebenenfalls verzweigtkettiger Rest,
R₃: H, -CH₃ oder -CH₂-CH₃.Preferably, the process is carried out in such a way that 1,3-bis (1-methyl-1-isocyanatoethyl) benzene or the carbodiimide obtainable from 1,3-bis (1-methyl-1-isocyanatoethyl) benzene with R ₃ -CCH ₂ -CO-R ₁ CH ₂ OH, particularly preferred

is reacted with the following meanings for R ₁ and R ₃ :
R ₁ : aliphatic, cycloaliphatic, araliphatic or aromatic, optionally substituted optionally branched-chain radical,
R ₃ : H, -CH ₃ or -CH ₂ -CH ₃ .

R ₁ , R ₂ , R ₃ and R ₄ particularly preferably have the following meanings:
R ₁ and R ₂ : -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ - and / or -CH ₂ -CH ₂ -CH ₂ -CH ₂ -,
R ₃ and R ₄ : -H and / or -CH ₃ , preferably -H.

essential to the invention Thus, the very low content of catalysts is that in the carbodiimide remains. While in EP-A 808 828 a catalyst is used which does not pass through Distillation is to be removed and also in the Scriptures at no It should be noted that the catalyst advantageously consists of the carbodiimide is removed, according to the invention by the removal of the catalyst significantly greater stability of the thermoplastic Polyurethane can be achieved.

The Preparation of the carbodiimides of the invention is well known and takes place essentially by two implementation steps. On the one hand (1) by well-known implementation of the isocyanate groups with elimination of carbon dioxide in the presence of methyl-2,5-dihydro-phospholene-1-oxides (CAS [930-38-1]) and / or 1-methyl-2,3-dihydro-phospholene-1-oxides (CAS [872-45-7]) as catalyst produces carbodiimide structures, on the other hand, (2) isocyanate groups with the corresponding hydroxyacrlyate and / or hydroxymethacrylate compound, preferably hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate and / or hydroxyethyl methacrylate, more preferably reacted 2-hydroxyethyl acrylate.

According to the invention you can the 1,3-bis (1-methyl-1-isocyanato-ethyl) benzene before the reaction for Carbodiimide with the corresponding hydroxyacrlyate or hydroxymethacrylate compound, preferably hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, Hydroxyethyl methacrylate, more preferably 2-hydroxyethyl acrylate implement. However, it is preferred that the carbodiimide with the corresponding Hydroxyacrlyate or hydroxymethacrylate compound, preferably hydroxyethyl acrylate, Hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, more preferably reacting 2-hydroxyethyl acrylate.

For example can be the carbodiimides of the invention to obtain 1,3-bis (1-methyl-1-isocyanatoethyl) benzene in the presence of methyl 2,5-dihydro-phospholene-1-oxides (CAS [930-38-1]) and / or 1-methyl-2,3-dihydro-phospholene-1-oxides CAS ([872-45-7]), preferably 1-methyl-2,3-dihydro-phospholene-1-oxides, reacted under carbon dioxide cleavage to carbodiimide and then the isocyanate group-containing Carbodiimide with the corresponding hydroxyacrlyate or hydroxymethacrylate compound, preferably hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, Hydroxyethyl methacrylate, more preferably 2-hydroxyethyl acrylate implements. The molar ratio the NCO groups of the isocyanate group-containing carbodiimide too the hydroxyl groups of the corresponding hydroxyacrlyate or hydroxymethacrlyate compound, preferably hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, Hydroxyethyl methacrylate, more preferably 2-hydroxyethyl acrylate is usually 10: 1 to 0.2: 1, preferably 5: 1 to 0.5: 1, more preferably 1: 1 to 0.5: 1, in particular 1: 1.

Alternatively, the carbodiimides according to the invention can be obtained by reacting 1,3-bis (1-methyl-1-isocyanatoethyl) benzene with a molar deficiency of corresponding hydroxyacrlyate or hydroxymethacrylate compound, preferably hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, Hydroxyethyl methacrylate, more preferably 2-hydroxyethyl acrylate and then reacting the isocyanate-containing reaction product in the presence of methyl-2,5-dihydrophospholen-1-oxides (CAS [930-38-1]) and / or 1-methyl-2,3-dihydro -phospholen-1-oxides (CAS [872-45-7]) with carbon dioxide release to carbodiimides. According to this process variant, initially up to 50% by weight, preferably up to 23% by weight, of the isocyanate groups of the diisocyanate are reacted with the corresponding hydroxyacrylate or hydroxymethacrylate compound, preferably hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, more preferably 2-hydroxyethyl acrylate and then the free isocyanate groups in the presence of catalysts under Kohlendioxidfreisetung completely or partially condensed to carbodiimides and / or oligomeric polycarbodiimides.

Prefers you lead first the conversion to the carbodiimides by and then sets the Isocyanate group-containing carbodiimide with the corresponding Hydroxyacrlyate or hydroxymethacrylate compound. Prefers indicates the product, i. containing the carbodiimide (i) according to the invention the acrylate groups have an NCO content of less than 1% by weight, especially preferably between 0.001% by weight and 0.5% by weight, in particular of 0 wt .-% to 0.5 wt .-% on.

Of the Process step (1) for the preparation of the carbodiimides according to the invention by reacting diisocyanates at elevated temperatures, e.g. at Temperatures from 50 to 200 ° C, preferably from 150 to 185 ° C be condensed. Therefor suitable methods are described, for example, in GB-A-1 083 410, DE-B 1 130 594 (GB-A-851 936) and DE-A-11 56 401 (US-A-3 502 722).

When Catalysts for the preparation of carbodiimides have proven excellent Methyl 2,5-dihydro-phospholene-1-oxides CAS [930-38-1] and / or 1-methyl-2,3-dihydrophospholen-1-oxide CAS [872-45-7], preferred 1-methyl-2,3-dihydro-phospholene-1-oxides. These catalysts have the important advantage of being distillative from the carbodiimide have it removed.

If the reaction mixture the desired Has content of NCO groups, the polycarbodiimide is usually completed. You can do this the catalysts are distilled off under reduced pressure or by Addition of a deactivator, e.g. Phosphorus trichloride, deactivated become. The catalysts are preferably distilled off. Prefers are carbodiimides according to the invention, containing a content of catalysts for the carbodiimide formation of less than 25 ppm in the final product. The polycarbodiimide production may also be in the absence or presence of under the reaction conditions inert solvents carried out become.

By suitable choice of the reaction conditions such as the reaction temperature, the type of catalyst and the catalyst amounts and the reaction time, the skilled person can adjust the degree of condensation in the usual way. The course of the reaction can be most easily followed by determining the NCO content. Other parameters such as viscosity increase, color well or CO ₂ evolution can also be used to track the process and control the reaction.

The carbodiimides according to the invention containing at least one, preferably one to twenty, carbodiimide structures, is particularly preferred the mean degree of condensation (number average), i. the middle Number of carbodiimide structures in the carbodiimides of the invention one to ten, more preferably 2 to 8, especially 4 to 6.

by virtue of good solubility in the building components for the production of polyurethanes and the good compatibility with the polyurethanes formed, the inventive (poly) carbodiimides are especially as stabilizers against the hydrolytic degradation of (Poly) -ester structure containing polyurethanes, preferably compact or cellular polyurethane elastomers and in particular thermoplastic Polyurethanes and cellular or compact elastomers.

The Concentration of the carbodiimides of the invention in the polycondensation-containing ester groups to be stabilized or polyaddition products in general from 0.05 to 10% by weight, preferably from 0.1 to 5% by weight, based on the total weight of the mixture. In individual cases, depending on the load of the plastic by hydrolysis, the concentration also higher be.

The carbodiimides which can be used according to the invention can be introduced by various methods into the products to be stabilized containing ester groups. For example, the carbodiimides according to the invention can be mixed with one of the synthesis components for the preparation of the polyaddition products, for example the polyisocyanates or / and polyhydroxyl compounds for the preparation of polyurethanes, or the carbodiimides can be added to the reaction mixture for the preparation of the polyurethanes. According to another procedure, the carbodiimides according to the invention can be incorporated into the melt of the fully reacted polyaddition or polycondensation products. However, it is also possible to coat granules of the polyaddition or polycondensation products with the carbodiimides according to the invention or to mix with the pulverized, pelletized or granulated carbodiimides of the invention and to introduce in a subsequent production of moldings by melt extrusion in the plastic compositions. For the production of polyurethane cast elastomers and polyester based TPU According to a preferred embodiment, the carboxyl-containing polyester polyols are first treated with the carbodiimides according to the invention to reduce the acid contents and then reacted with polyisocyanates, optionally with the addition of further amounts of carbodiimides, if appropriate in the presence of additional auxiliaries and additives. Furthermore, the carbodiimides according to the invention can be introduced into the polyurethane via the isocyanate component. However, the carbodiimides according to the invention are particularly useful if they are introduced into the ester-group-containing polymer during the customary preparation.

Especially The carbodiimides of the invention are preferred in the preparation of polyurethanes, e.g. cellular, for example microcellular polyurethanes, preferably polyurethane elastomers, in particular thermoplastic Polyurethanes used. The preparation of these polyurethanes, in particular Polyurethane elastomers can by known implementation of conventional Output components, i. Isocyanates, isocyanate-reactive compounds, optionally propellants, preferably water and optionally Catalysts, auxiliaries and / or additives in the presence of the carbodiimides of the invention take place. In this case, the carbodiimides according to the invention are preferably added to the component, which contains the propellant, preferably water.

Prefers Thus, processes for the preparation of polyurethanes are preferred thermoplastic polyurethanes preferably by reaction of isocyanates, across from Isocyanate-reactive compounds, optionally blowing agents and optionally catalysts, auxiliaries and / or additives, wherein the reaction in the presence of the carbodiimides of the invention performs.

use can the thermoplastic according to the invention processable polyurethane elastomers for extrusion, injection molding, calendar articles also for Powder-slush process Find.

Prefers become the carbodiimides invention used in thermoplastic polyurethanes.

The Processing of the invention produced TPUs, usually as granules or in powder form, to injection molding and extrusion articles, e.g. the wished Films, molded parts, rolls, fibers, linings in automobiles, hoses, Cable plugs, bellows, Towing cables, cable sheathing, seals, belts or damping elements takes place according to usual Methods, e.g. Injection molding or extrusion. Such injection molding and extrusion articles also from compounds containing the TPU according to the invention and at least one another thermoplastic, especially a polyethylene, Polypropylene, polyester, polyether, polystyrene, PVC, ABS, ASA, SAN, Polyacrylonitrile, EVA, PBT, PET, polyoxymethylene. Especially let yourself the inventively prepared Use TPU for the production of the articles presented at the beginning.

kleiner 100 ppm, bevorzugt kleiner 50 ppm, besonders bevorzugt kleiner 25 ppm, insbesondere kleiner 10 ppm, bezogen auf das eingesetzte Carbodiimid ist.The invention thus also relates to polyurethanes, in particular thermoplastic polyurethanes containing carbodiimide obtainable by the process according to the invention, in particular polyurethanes, preferably thermoplastic polyurethanes, in which the content of

less than 100 ppm, preferably less than 50 ppm, more preferably less than 25 ppm, in particular less than 10 ppm, based on the carbodiimide used.

• • Verbesserte hydrolytische Beständigkeit bei Lagerung in Wasser bei 80°C
• • Verbesserung (Erhöhung) der Zugfestigkeit und Reißdehnung bei Lagerung unter Wasser
• • Verringerung der Quelleigenschaften
• • Erhöhung der Wännefonnbeständigkeit
• • Erhöhung der HDT
• • Erhöhung des E-Modlus
• • Erhöhung der Vicat-Temperatur

The TPUs produced with the carbodiimides according to the invention have the following advantages over conventional carbodiimides:

• • Improved hydrolytic stability when stored in water at 80 ° C
• • improvement (increase) in tensile strength and elongation at break when stored under water
• • Reduction of swelling properties
• • Increasing the resistance of the telephone
• • increase the HDT
• • Increase the e-modus
• • increase the Vicat temperature

Example 1:

Preparation of stabilizers according to the invention: Isocyanate-stage

1000 Parts by weight (4.1 mol) of 1,3-bis (1-methyl-1-isocyanatoethyl) benzene with an NCO content of 34.4 wt .-% were in the presence of 2.0 Parts by weight of a mixture of 1-methyl-2,5-dihydro-phospholene-1-oxides and 1-methyl-2,3-dihydrophospholen-1-oxides solvent-free to 180 ° C heated and at this temperature with moderate evolution of carbon dioxide condensed. After reaching an NCO content of the reaction mixture of 10% by weight, this was a reaction time of about 24 hours required, the added catalyst and residues of not reacted 1,3-bis (1-methyl-1-isocyanato-ethyl) -benzols in a Temperature of 190 ° C and distilled off under a pressure of 0.2 mbar.

you received 730 parts by weight of a mixture of mono- and oligomeric polycarbodiimides with an NCO content of 8 wt .-%, a content of -N = C = N groups of 15%, a melting point <30 ° C and a Iodine color number of 4.0, measured according to DIN 6162.

The structure of the isocyanate-containing mixture of mono- and oligomeric polycarbodiimides was detected by ¹ H-NMR and IR spectrum.

Example 2: Preparation Stabilizers according to the invention: urethane

The Product of Example 1 was heated to 100 ° C. Under intense stir were within about 30 min in each case in Table 1 indicate Amounts of corresponding hydroxyacrlyate or hydroxymethacrlyate compound added. Subsequently the reaction mixture was stirred at 120 ° C for a further 2h.

Table 1

The structures of the resulting acrlyate carbodiimides and methacrylate carbodiimides were detected by ¹ H NMR and IR spectra.

Example 3: Production of TPU samples

Polyol 1)

Polyester polyol (Lupraphen VP ^® 9329, BASF Aktiengesellschaft; butanediol / 3-methyl-propanediol adipate, molecular weight 2,000, OH value = 56.1)

Polyol 2)

Polyester polyol (Lupraphen ^® 8110, BASF Aktiengesellschaft; butanediol / ethylene glycol adipate, molecular weight 2,000, OH value = 56.1)

The in Table 2 specified polyols were at 80 ° C with 1,4-butanediol mixed. Then took place with stirring the addition of the various hydrolysis stabilizers as in Table 2 listed.

Table 2

• Elastostab® ^® H01: polymeric carbodiimide (hydrolysis stabilizer) Elastogran GmbH
• Stabaxol ^® 1: monomeric carbodiimide (Antihydrolysis) of Rhein Chemie GmbH
• Stabilizer 1 to 4: stabilizers prepared in Example Second

The Glycol mixture was stirred at 80 ° C tempered.

After that were 425 g of 4,4'-MDI (Methylendiphenyldiisocyanat) was added and stirred until the Reaction mixture was homogeneous. Subsequently, the mixture was in poured a flat Teflon dish and at 125 ° C on a hot plate for 10 min annealed. The resulting TPU rind was in a heating cabinet 24 h at 100 ° C annealed. After granulating the casting plates, these were placed on a Injection molding machine processed to 2 mm splash plates. The mechanical Values were determined and are listed in Table 3.

Table 3

Table 4

Determination of hydrolysis resistance

It were punched from the spray plates S2 specimens, these in glasses (250 and 500 ml) with distilled water and placed in a temperature control cabinet defined temperature (80 ° C) posed. At certain intervals (for example weekly) three specimens were taken. Thereafter, the samples were min. Stored for 30 minutes in standard climate 23/50 and tensile strength and elongation at break certainly.

Table 5: Measurement of tensile strength [MPa] as a function of time [days]

Table 6: Measurement of elongation at break [%] as a function of time [days]

Table 7: Measurement of tensile strength [MPa] as a function of time [days]

Table 8: Measurement of elongation at break [%] as a function of time [days]

Claims (8)

Carbodiimide (i) having the structure:

with the following meanings for n, R ₁ , R ₂ , R ₃ and R ₄ : n: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 13, 14 , 15, 16, 17, 18, 19 or 20, R ₁ : aliphatic, cycloaliphatic, araliphatic or aromatic, optionally substituted Gegebe where appropriate, branched-chain radical, R ₂ : aliphatic, cycloaliphatic, araliphatic or aromatic, optionally substituted, optionally branched-chain radical, R ₃ : H, -CH ₃ or -CH ₂ -CH ₃ , R ₄ : H, -CH ₃ or -CH ₂ - CH ₃ , characterized in that the content of 1-methyl-2,5-dihydro-phospholene-1-oxides and 1-methyl-2,3-dihydro-phospholene-1-oxides is less than 100 ppm, by weight of carbodiimide (i). Process for the preparation of the following carbodiimide (i):

with the following meanings for n, R ₁ , R ₂ , R ₃ and R ₄ : n: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 13, 14 , 15, 16, 17, 18, 19 or 20, R ₁ : aliphatic, cycloaliphatic, araliphatic or aromatic, optionally substituted optionally branched-chain radical, R ₂ : aliphatic, cycloaliphatic, araliphatic or aromatic, optionally substituted optionally branched-chain radical, R ₃ : H, -CH ₃ or -CH ₂ -CH ₃ , R ₄ : H, -CH ₃ or -CH ₂ -CH ₃ , characterized in that 1,3-bis (1-methyl-1-isocyanato-ethyl ) benzene in the presence of 1-methyl-2,5-dihydro-phospholene-1-oxides and / or 1-methyl-2,3-dihydro-phospholene-1-oxides to give carbodiimide and 1-methyl-2.5 -dihydro-phospholene-1-oxides and / or 1-methyl-2,3-dihydro-phospholene-1-oxides removed from the carbodiimide until the content of 1-methyl-2,5-dihydro-phospholene-1-oxides and 1-methyl-2,3-dihydro-phospholene-1-oxide is less than 100 ppm, based on the weight of the carbodiimide ( i). A method according to claim 2, characterized in that 1,3-bis (1-methyl-1-isocyanato-ethyl) benzene or that of 1,3-bis (1-methyl-1-isocyanato-ethyl) benzene carbodiimide obtainable with R ₃ -CCH ₂ -CO-R ₁ CH ₂ OH is reacted with the following meanings for R ₁ and R ₃ : R ₁ : aliphatic, cycloaliphatic, araliphatic or aromatic, optionally substituted optionally branched chain radical, R ₃ : H , -CH ₃ or -CH ₂ -CH ₃ . A method according to claim 2, characterized in that R ₁ , R ₂ , R ₃ and R _{4 have} the following meanings: R ₁ and R ₂ : -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ - and / or -CH ₂ -CH ₂ -CH ₂ -CH ₂ -R ₃ . R ₃ and R ₄ : -H and / or -CH ₃ . Method according to one the claims 2 to 4, characterized in that the 1,3-bis (1-methyl-1-isocyanato-ethyl) benzene before the reaction to carbodiimide with the corresponding hydroxyacrylate or Hydroxy methacrylate compound implements. Method according to one the claims 2 to 4, characterized in that the carbodiimide with the corresponding hydroxyacrlyate or hydroxymethacrylate compound to carbodiimide (i). Polyurethanes containing carbodiimide obtainable by a method according to a the claims 2 to 6. Polyurethanes according to claim 7, characterized in that the content of 1-methyl-2,5-dihydro-phospholene-1-oxides and 1-methyl-2,3-dihydro-phospholene-1-oxides less than 100 ppm, based on the carbodiimide used is.