EP2389405A1 - Polyurethane casting compounds - Google Patents

Abstract

The invention relates to the use of polyurethane casting compounds for producing light-resistant compact or expanded polyurethane or polyurethane urea bodies that are characterized by exceptionally good mechanical and visual properties and particularly have a very high heat shape retention.

Description

 Polyurethanvergussmassen

The preparation of lightfast polyurethane or polyurethane urea elastomers using aliphatic and / or cycloaliphatic polyisocyanates is known.

For a number of different applications, for example, as a replacement for mineral glass for the production of glass for automotive and aircraft, for the production of optical lenses and lenses or as Vergussmassen for electronic or optoelectronic components, there is now an increasing interest in the market for hard, light and weather-resistant polyurethane and polyurethaneurea compositions.

The preparation of hard lightfast polyurethane or polyurethane urea elastomers has already been described several times. As a rule, come as polyisocyanate the industrially available aliphatic and / or cycloaliphatic diisocyanates such. For example, 1,6-diisocyanatohexane (HDI), 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate, IPDI) and / or 2,4'- and / or 4,4 '. Diisocyanatodicyclohexylmethan (Hi ₂ -MDI) or oligomeric derivatives of these diisocyanates used. For example, WO 1996/023827 describes transparent, high-hardness and impact-resistant polyurethaneurea compositions suitable for the production of automotive windows or safety glass, which are prepared by reacting semiprepolymers based on 4,4'-diisocyanatodicyclohexylmethane with substituted 4,4'-methylenebis-anilines.

An improved process for preparing such polyurethaneurea compositions which are suitable as glass substitutes, in which isocyanate-functional semiprepolymers are cured using diethyltoluene-diamine (DETDA) as the aromatic diamine, is known from WO 2003/072624.

Transparent, hard polyurethaneurea masses of good heat resistance, which can serve as material for spectacle lenses, can be similarly prepared according to the teaching of WO 2000/014137 from polyurethane prepolymers based on aliphatic and / or cycloaliphatic diisocyanates and at least one aromatic diamine or WO 2004/076518 Curing of isocyanate prepolymers with crosslinker mixtures consisting of hydroxy-functional polyurethane prepolymers and aromatic diamines obtained.

Although the use of aromatic diamines as chain extenders allows the preparation of polyurethane urea compositions with the desired high hardness and heat resistance according to the above methods, but at the same time leads to insufficient color stability. The yellowing of such compositions can be suppressed for a limited time by the addition of high levels of UV stabilizers and antioxidants, as described, for example, in WO 2008/033659, but sooner or later inevitably occurs. The production of compact, transparent polyurethane compositions which are free of urea groups and nevertheless suitable as a glass substitute is the subject of EP-A 0 943 637. In order to be able to realize sufficiently high hardnesses, however, one must rely on the use of very specific highly functional polyol mixtures in this process , However, all previously mentioned processes for producing lightfast, hard polyurethane and polyurethaneurea compositions or bodies obtainable from them have the considerable disadvantage that they work with large quantities of low molecular weight monomeric diisocyanates which are classified as toxic working substances and in some cases have a high vapor pressure. The processing of these monomeric diisocyanates requires a great safety outlay for reasons of occupational hygiene. Moreover, there is the possibility that, in particular when using a polyisocyanate excess, such. As proposed in WO 2008/033659, unreacted monomeric diisocyanate for a long time in the molded part produced, for. As a lens, remains and can evaporate from this slowly.

There has been no lack of attempts to provide polyurethane compositions for producing lightfast hard molded articles based on low monomer, high molecular weight, physiologically acceptable polyisocyanates, in particular those based on the bckänütcü emphatic FölyiSuuyciiiciie with BiureL-, isocyanurate or Uretdionstruktur provide.

The liquid at the processing temperature in solvent-free form polyisocyanates based on linear aliphatic diisocyanates such. B. HDI trimers, but even in combination with the described in EP-B 0 943 637 special high-functionality polyol mixtures only to products with comparatively low glass transition temperature (T _g ) and correspondingly low heat resistance, as Example 1 of this publication can be found.

On the other hand low-monomer polyisocyanates based on cycloaliphatic diisocyanates provide for Verarbeitungstemeratur are solid compounds that have melting points in the range of 80 ° to 120 ⁰ C in the rule. Their use as crosslinking component for light-fast polyurethane casting compounds has hitherto always been possible only with the concomitant use of large amounts of monomeric diisocyanates as reactive diluents (see, for example, DE-A 2 900 031), which in turn is associated with the occupational hygiene disadvantages discussed above.

It is an object of the present invention to provide novel hard, light-stable and weather-resistant polyurethane and polyurethaneurea compositions which do not have the disadvantages of the known systems. The new polyurethane compositions should be based on toxicologically harmless raw materials and can be processed by conventional methods, for example by simple casting by hand or with the help of suitable machines, for example according to the REvI method, to highly crosslinked, heat-resistant moldings. This problem could be solved by providing the polyurethanes or polyurethane ureas described in more detail below.

The invention described in more detail below is based on the surprising observation that light-fast compact or foamed polyurethane or polyurethane urea bodies can be produced using trimerates of cycloaliphatic diisocyanates with solvent-free mixtures of low-viscosity HDI polyisocyanates which are distinguished by extraordinarily good mechanical and optical properties and in particular have a very high heat resistance.

Such solutions of solid or extremely high-viscosity cycloaliphatic polyisocyanurates in low-viscosity HDI polyisocyanates are known, for example, from EP-A 0 693 512 as crosslinker components for solvent-free polyols for producing hard-elastic, highly abrasion-resistant coatings, in particular for balcony or roof waterproofing. Although it is generally stated in this publication that such systems are also suitable for the production of lightfast, hard casting compounds, the skilled person, however, was unable to provide any concrete indications of the particular suitability of such polyisocyanate mixtures as starting components for the production of compact and foamed cellulose or cellulose. Polyurethane urea body high heat resistance or on the excellent optical properties so obtainable polyurethane molded body.

Solvent-free polyisocyanate mixtures consisting of HDI polyisocyanates, preferably HDI trimers, and polyisocyanates based on cycloaliphatic diisocyanates are also described in EP-A 1 484 350 as crosslinkers for very special solvent-free polyester polyols having a functionality of less than 3 in solvent-free coating compositions. In these two-component systems, which are used in particular for coating decorative parts with low thermal transfer, for example those in root wood optics, as they are increasingly used today in the automotive or furniture industry, the use of special polyisocyanate mixtures leads to glass transition temperatures (Tg) of over 70 ° C and thus allows any necessary repolishing the finished coated components. As a preferred mode of application for the systems described, EP-A 1 484 350 also mentions reaction injection molding (RJM) in closed molds, but the publication does not contain any concrete description for the production of solid, compact or even foamed moldings exclusively the coating of suitable substrates on the subject. Moreover, here, too, for example, any reference to the high optical quality and excellent heat resistance of the present invention available polyurethane or polyurethane urea. Due to the published concrete By way of example, it is even the case that the described low-monomer polyisocyanate mixtures cure only in combination with very specific, ether group-free polyester polyols based on aromatic carboxylic acids to give low-yellowing, hard and transparent polyurethanes. According to our own experiments, the comparative tests described in EP-A 1 484 350, which result in soft, matt or cloudy lacquer coatings, are not representative individual cases. As described in more detail below, the polyisocyanate mixtures which can be used according to the invention as crosslinkers in polyurethane or polyurethaneurea compositions can be combined without problems with a large number of different, even highly functional reactants, including ether-containing polyols or aromatic-free polyesterpolyols, to give transparent hard-setting systems of high optical brilliance ,

The present invention is the use of solvent-free, low-monomer polyisocyanate components A), which at 23 ° C, a viscosity of 2,000 to 100,000 mPas, a content of isocyanate groups of 13 to 23 wt .-% and an average isocyanate functionality of at least , 5, and to 30 to 95 wt .-% of at least one polyisocyanate AI) based on hexamethylene diisocyanate having an NCO content of 16 to 24 wt .-% and 20 to 60 wt .-% auς at least one polyisocyanate a-2) based on cycloaliphatic diisocyanates having an NCO content of 10 to 22 wt .-%, for the production of light-fast compact or foamed polyurethane and / or Poryharnstoff body.

The subject of the invention is also a process for producing light-fast polyurethane and / or polyurea body by solvent-free implementation of

A) a low-monomer polyisocyanate component having at 23 ° C has a viscosity of 2,000 to 100,000 mPas, a content of isocyanate groups of 13 to 23 wt .-% and an average isocyanate functionality of at least 2.5, and the 30th to 95 wt .-% of at least one polyisocyanate a-1) based on hexamethylene diisocyanate having an NCO content of 16 to 24 wt .-% and to 5 to 70 wt .-% of at least one polyisocyanate a-2) based cycloaliphatic diisocyanates having an NCO content of 10 to 22 wt .-%, consists, with

B) to isocyanate-reactive reactants having an average functionality of 2.0 to 6.0 and optionally with concomitant use

C) further auxiliaries and additives, while maintaining an equivalent ratio of isocyanate groups to isocyanate-reactive groups of 0.5: 1 to 2.0: 1. Finally, the invention also relates to the use of the lightfast polyurethane and / or polyurea by-products obtainable in this way for producing transparent, compact or foamed moldings. The polyisocyanate component A) used for the preparation of the novel lightfast polyurethane or polyurea inks is solvent-free mixtures of 30 to 95% by weight of at least one polyisocyanate a-1) based on HDI and 5 to 70% by weight of at least one Polyisocyanate a-2) based on cycloaliphatic diisocyanates.

The polyisocyanates a-1) are the uretdione, isocyanurate, iminooxadiazinedione, urethane, allophanate, biuret and / or oxadiazinetrione group-containing derivatives of HDI, which have a viscosity of 80 at 23 ° C. to 12,000 mPas, a content of isocyanate groups of 16 to 25 wt .-%, a content of monomeric HDI of less than 0.5 wt .-% and an average isocyanate functionality of at least 2.0.

These are exemplified in Laas et al, J. Prakt. Chem. 336, 1994, 185-200, DE-A 1 670 666, DE-A 3 700 209, DE-A 3 900 053, EP-A 0 330 966, EP-A 0 336 205, EP-A 0 339,396 and EP-A 0 798 299.

The polyisocyanates of component a-1) are preferably HDI-based polyisocyanates of the abovementioned type with uretdione, allophanate, isocyanurate and / or iminooxadiazinetrione structure, which at 23 ° C. has a viscosity of from 100 to 1,600 mPas and a content of isocyanate groups of 18 to 24.5 wt .-% have.

The polyisocyanates of component a-1) are particularly preferably HDI polyisocyanates containing isocyanurate groups and / or iminooxadiazinedione groups of the abovementioned type having a viscosity at 23 ° C. of from 300 to 1500 mPas and a content of isocyanate groups of 20 to 24 wt .-%. The polyisocyanates of component a-2) are the per se known allophanate, biuret, isocyanurate, uretdione and / or urethane group-containing polyisocyanates based on cycloaliphatic diisocyanates which are present in solid form at 23.degree have a viscosity of more than 200,000 mPas, and their content of isocyanate groups of 10 to 25 wt .-% and monomeric diisocyanates is less than 0.5 wt .-%. Suitable cycloaliphatic starting diisocyanates for preparing the polyisocyanate components a-2) are, for example, 1,3- and 1,4-diisocyanatocyclohexane, 1,4-diisocyanato-3,3,5-trimethylcyclohexane, 1,3-diisocyanato-2-methylcyclohexane, 1, 3-diisocyanato-4-methylcyclohexane, IPDI, 1-isocyanato-1-methyl-4 (3) isocyanatomethylcyclohexane, 2,4'- and 4,4'-diisocyanatodicyclohexylmethane, 1,3- and 1,4- Bis (isocyanatomethyl) cyclohexane, 4,4'-diisocyanato-3,3'-dimethyldicyclohexylmethane, 4,4'-diisocyanato-S, 3'-S'-tetramethyldicyclohexylmethane, 4,4'-diisocyanato-1, bi (cyclohexyl), 4,4'-diisocyanato-3,3'-dimethyl-1, 1'-bi (cyclohexyl), 4,4'-diisocyanato-2,2 ', 5,5'-tetra- Methyl-l, r-bi (cyclohex- yl) and any mixtures of these diisocyanates. The polyisocyanates of component a-2) are preferably compounds of the abovementioned type with isocyanurate groups which are known per se and are described by way of example in Laos et al., J. Prakt. Chem. 336, 1994, 185-200, EP-A 0 003 765, EP-A 0 017 998, EP-A 0 193 828, DE-A 1 934 763 and DE-A 2 644 684.

The polyisocyanates of component a-2) are particularly preferably those of the type described above based on IPDI and / or 2,4'- and 4,4'-diisocyanatodicyclohexylmethane with a content of isocyanate groups of 13 to 19 wt .-%.

Very particularly preferred polyisocyanates of component a-2) are those of the type described above based on IPDI with an isocyanate group content of 15 to 18% by weight.

Both the HDI used for the preparation of the polyisocyanate component a-1) and the stated cycloaliphatic starting diisocyanates for the polyisocyanate components a-2) can be prepared by any desired method, for example by using B. by phosgenation or phosgene-free way, for example by urethane cleavage, are produced.

The polyisocyanate component A) present in the compositions which can be prepared or used according to the invention is prepared by simply mixing the individual components a-1) and a-2) preheated to temperatures of 30 to 240 ° in the quantitative ratio given above, preferably while maintaining a weight ratio a -1): a-2) from 90:10 to 35:65, more preferably from 80:20 to 40:60, and then stirring the mixture to homogeneity, the temperature of the mixture optionally being raised by further heating to a temperature of 30 to 140 ⁰ C, preferably 40 to 100 ⁰ C is maintained. In a preferred embodiment, in the preparation of the polyisocyanate component A), the polyisocyanate component a-2 which is highly viscous or solid at 23 ° C. is allowed to undergo catalytic trimerization of cycloaliphatic diisocyanates immediately after preparation by thin-layer distillation in still heated state, for example at temperatures from 100 to 240 ⁰ C, in which optionally also heated polyisocyanate component a-1) and stir, optionally with further heating to homogeneity of the mixture. In another, likewise preferred embodiment, in the preparation of the polyisocyanate component A), the polyisocyanate component a-1) is stirred into the polyisocyanate component a) used in the preparation of the polyisocyanate component A). cyanate component a-2) present after completion of the trimerization reaction crude solution before the thin-film distillation and separates only then from the excess monomeric cycloaliphatic diisocyanates.

Irrespective of the nature of their preparation, the polyisocyanate components A) are generally obtained as clear, practically colorless resins whose viscosity at 23 ° C. is preferably from 6,000 to 60,000 mPas, particularly preferably from 8,000 to 50,000 mPas, whose isocyanate group content is preferably from 15 to 22 wt .-%, particularly preferably from 16 to 21 wt .-%, and their average isocyanate functionality is preferably from 2.8 to 5.0, more preferably 3.0 to 4.5. The polyisocyanate component A) is low in residual monomers, since it has a residual content of monomeric diisocyanates (total of monomeric HDI and monomeric cycloaliphatic diisocyanates) of less than 1 wt .-%, preferably less than 0.5 wt .-%, more preferably less than 0.3% by weight.

For the preparation of light-fast polyurethane according to the invention and / or polyurea, the polyisocyanate components A) described above with any lösemittelfrei- en isocyanate-reactive reaction partners B) are reacted, the vorzu a mean in the sense of Isocyan2t-Additionεreaktion functionality of from 2 0 to 6 0 ^g have from 2 5 to 4 0 particularly preferably from 2.5 to 3.5.

These are, in particular, the customary polyether polyols known from polyurethane chemistry, polyester polyols, polyether polyester polyols, polythioether polyols, polymer-modified polyether polyols, graft polyether polyols, in particular those based on styrene and / or acrylonitrile, polyether polyamines, hydroxyl-containing polyacetals and / or hydroxyl groups. containing aliphatic polycarbonates, which usually have a molecular weight of 106 to 12,000, preferably 250 to 8,000. A broad review of suitable reactants B) can be found, for example, in N. Adam et al .: "Polyurethanes", Ullmann's Encyclopedia of Industrial Chemistry, Electronic Release, 7th ed., Chap. 3.2 - 3.4, Wiley-VCH, Weinheim 2005.

Suitable polyether polyols B) are, for example, those of the type mentioned in DE-A 2 622 951, column 6, line 65 - column 7, line 47, or EP-A 0 978 523 page 4, line 45 to page 5, line 14 if they correspond to the statements made above in terms of functionality and molecular weight, preference being given to those polyether polyols whose hydroxyl groups consist of at least 50%, preferably at least 80%, of primary hydroxyl groups. Particularly preferred polyether polyols B) are adducts of ethylene oxide and / or propylene oxide with glycerol, trimethylolpropane, ethylenediamine and / or pentaerythritol.

Suitable polyester polyols B) are, for example, those of the type mentioned in EP-A 0 978 523, page 5, lines 17 to 47 or EP-A 0 659 792, page 6, lines 8 to 19, provided that the above correspond to statements made, preferably those whose hydroxyl number is from 20 to 650 mg KOH / g.

Suitable polythiopolyols B) are, for example, the known condensation products of thiodiglycol with itself or other glycols, dicarboxylic acids, formaldehyde, aminocarboxylic acids and / or aminoalcohols. Depending on the type of mixed components used, these are polythiomethane ether polyols, polythioether ester polyols or polythioether ester amide polyols.

As component B) suitable polyacetal polyols are, for example, the known reaction products of simple glycols, such as. As diethylene glycol, triethylene glycol, 4,4'-dioxethoxy-di-phenyl-dimethylmethane (adduct of 2 moles of ethylene oxide with bisphenol A) or hexanediol, with formaldehyde or by polycondensation of cyclic acetals, such as. As trioxane, prepared polyacetals.

In addition, aminopolyethers or mixtures of aminopolyethers are also very suitable as component B), ie. H. Polyether with isocyanate-reactive groups which are at least 50 equivalent%, preferably at least 80 equivalent% of primary and / or secondary, aromatic or aliphatic bound amino groups and the remainder of primary and / or secondary, aliphatically bound hydroxyl groups , Suitable such aminopolyethers are, for example, the compounds mentioned in EP-A 0 081 701, column 4, line 26 to column 5, line 40. Likewise suitable as starting component B) are amino-functional polyether urethanes or ureas, as can be prepared, for example, by the process of DE-A 2 948 419 by hydrolysis of isocyanate-functional polyether prepolymers or also amino-containing polyesters of the abovementioned molecular weight range.

Other suitable isocyanate-reactive components B) are, for example, those described in EP-A 0 689 556 and EP-A 0 937 110, z. Example by reacting epoxidized fatty acid esters with aliphatic or aromatic polyols with Epoxidringöffung available special polyols.

Also, hydroxyl-containing polybutadienes may optionally be used as component B). For the preparation of bodies of polyurethane and / or polyurea, which have a particularly high refraction, are suitable as isocyanate-reactive components B) in particular polymercaptans, ie polythio, for example, simple alkanethiols such. Methanedithiol, 1,2-ethanedithiol, 1,1-propanedithiol, 1,2-propanedithiol, 1,3- Propanedithiol, 2,2-propanedithiol, 1,4-butanedithiol, 2,3-butanedithiol, 1,5-pentanedithiol, 1,6-hexanedithiol, 1,2,3-propanetrithiol, 1,1-cyclohexanedithiol, 1, 2-cyclohexanedithiol, 2,2-dimethylpropane-1,3-dithiol, 3,4-dimethoxybutane-l, 2-dithiol and 2-methylcyclohexane-2,3-dithiol, thioether group-containing polythiols, such as. For example, 2,4-dimercaptomethyl-l, 5-dimercapto-3-thiapentane, 4-mercaptomethyl-ljS-dimercapto-Sjό-dithiaoctane, 4,8-dimercaptomethyl-l, l l dimercapto-3,6,9-tri thiaundecane, 4,7-dimercaptomethyl-1,1,1-dimercapto-3,6,9-trithiaundecane, 5,7-dimercaptomethyl-1,1,1-dimercapto-3,6,9-trithiaundecane, 4,5-bis (mercaptoethylthio) -l, 10-dimercapto-3,8-dithia-decane, tetrakis (mercaptomethyl) methane, 1,1,3,3-tetrakis (mercaptomethylthio) propane, 1,1,5,5-tetrakis (mercaptomethylthio) 3-thiapentane, 1,1,6,6-tetrakis (mercaptomethylthio) -3,4-dithiahexane, 2-mercaptoethylthio-1, 3-dimercaptopropane, 2,3-bis (mercaptoethylthio) -1-mercaptopropane, 2,2 Bis (mercaptomethyl) -1,3-dimercaptopropane, bis (mercaptomethyl) sulfide, bis (mercaptomethyl) disulfide, bis (mercaptoethyl) sulfϊd, bis (mercaptoethyl) disulfide, bis (mercaptopropyl) sulfide, bis (mercaptopropyl) disulfide, bis (mercaptomethylthio) methane, tris (mercaptomethylthio) methane, bis (mercaptoethylthio) methane, tris (mercaptoethylthio) methane, bis (mercaptopropylthio) methane, 1,2- Bis (mercaptomethylthio) ethane, 1,2-bis (mercaptoethylthio) ethane, 2-mercaptoethylthio) ethane, 1,3-bis (mercaptomethylthio) propane, 1, 3-bis (mercaptopropylthio) propane, 1, 2,3-tris ( mercaptomethylthio) propane, 1,2,3-tris (mercaptoethylthio) propane, 1,2,3-tris (mercapto-propylthic) propane, tetrakis (mercaptomethylthio) methane, tetrakis (mercaptoethylthiomethyl) methane, tetrakis (mercaptopropylthiomethyl) methane , 2,5-Dimercapto-l, 4-dithiane, 2,5-bis (mercaptomethyl) -l, 4-dithiane and its oligomers according to JP-A 07 118 263, 1, 5-bis (mercaptopropyl) - 1,4-dithiane, 1,5-bis (2-mercaptoethylthiomethyl) -1,4-dithiane, 2-mercaptomethyl-6-mercapto-1,4-dithiacycloheptane, 2,4,6-trimercapto-l, 3,5 trithiane, 2,4,6-trimercaptomethyl-l, 3,5-trithiane and 2- (3-bis (mercaptomethyl) -2-thiapropyl) -1,3-dithiolane, polyester thiols, e.g. Ethylene glycol bis (2-mercaptoacetate), ethylene glycol bis (3-mercaptopropionate), diethylene glycol (2-mercaptoacetate), diethylene glycol (3-mercaptopropionate), 2,3-dimercapto-1-propanol (3 mercaptopropionate), 3-mercapto-1, 2-propanediol bis (2-mercaptoacetate), 3-mercapto-1,2-propanediol bis (3-mercaptopropionate), trimethylolpropane tris (2-mercaptoacetate), trimethylolpropane tris ( 3-mercaptopropionate), trimethylolethane tris (2-mercaptoacetate), trimethylolethane tris (3-mercaptopropionate), pentaerythritol tetrakis (2-mercaptoacetate), pentaerythritol tetrakis (3-mercaptopropionate), glycerol tris (2-mercaptoacetate ), Glycerol tris (3-mercaptopropionate), 1,4-cyclohexanediol bis (2-mercaptoacetate), 1,4-cyclohexanediol bis (3-mercapto propionate), hydroxymethyl sulfide bis (2-mercaptoacetate), hydroxymethyl sulfide bis (3-mercapto propionate), hydroxyethyl sulfide (2-mercaptoacetate), hydroxyethyl sulfide (3-mercaptopropionate), hydroxymethyl disulfide (2-mercaptoacetate), hydroxymethyl disulfide (3-mercaptopropionate), (2-mercaptoacetate) methyl ester) thioglycolate and bis (2-mercaptoethyl ester) thiodipropionate and also aromatic thiol compounds, such as, for example, B. 1, 2-dimercaptobenzene, 1, 3-dimercaptobenzene, 1, 4-dimercaptobenzene, 1, 2-bis (mercaptomethyl) benzene, 1, 4-bis (mercaptomethyl) benzene, 1, 2-bis (mercaptoethyl) benzene, 1,4-bis (mercaptoethyl) benzene, 1,2,3-trimercaptobenzene, 1,2,4-trimercaptobenzene, 1,3,5-tri-mercaptobenzene, 1,2,3-tris (mercaptomethyl) benzene, 1, 2,4-tris (mercaptomethyl) benzene, 1,3,5-tris (mercaptomethyl) benzene, 1,2,3-tris (mercaptoethyl) benzene, 1,3,5-tris (mercaptoethyl) benzene, 1,2 , 4-tris (mercaptoethyl) benzene, 2,5-toluenedithiol, 3,4-toluenedithiol, 1,4-naphthalenedithiol, 1,5-naphthalenedithiol, 2,6-naphthalenedithiol, 2,7-naphthalenedithiol, 1,2 , 3,4-tetramercaptobenzene, 1,2,3,5-tetramercaptobenzene, 1, 2,4,5-tetramercaptobenzene, 1, 2,3,4-tetrakis (mercaptomethyl) benzene, 1, 2,3,5-tetrakis (mercaptomethyl) benzene, 1, 2,4,5-tetrakis (mercaptomethyl) benzene, 1, 2,3,4-tetrakis (mercaptoethyl) benzene, 1, 2,3,5-tetrakis (mercaptoethyl) benzene, 1 , 2,4,5-tetrakis (mercaptoethyl) benzene, 2,2'-dimercaptobiphenyl and 4,4'-dimercaptobiphenyl. Preferred polythio compounds B) are polythioetherthiols and polyester thiols of the type mentioned. Particularly preferred polythio compounds B) are 4-mercaptomethyl-1,8,8-dimercapto-3,6-dithiaoctane, 2,5-bismercaptomethyl-1,4-dithiane, 1, 3,3-tetrakis (mercaptomethylthio) propane, 5,7-dimercaptomethyl-1,1,1-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,1,1-dimercapto-3,6,9- trithiaundecane, 4,8-dimercaptomethyl-1,1,1-dimercapto-3,6,9-trithiaundecane, trimethylolpropane tris (3-mercaptopropionate), trimethylolethane tris (2-mercaptoacetate), pentaerythritol tetrakis (2 mercaptoacetate) and pentaerythritol tetrakis (3-mercaptopropionate).

In addition, sulfur-containing hydroxy compounds are also suitable as isocyanate-reactive components B). Examples which may be mentioned here are simple mercapto alcohols, such as. B. 2-mercaptoethanol, 3-mercaptopropanol, l, 3-dimercapto-2-propanol, 2,3-di-mercaptopropanol and dithioerythritol, thioether containing alcohols such. Di (2-hydroxyethyl) sulphide, 1, 2-bis (2-hydroxyethylmercapto) ethane, bis (2-hydroxyethyl) disulfide and 1, 4-dithian-2,5-diol, or sulfur-containing diols with polyester urethane, Polythioesterurethan-, Polyesteerthiourethan- or Polythioesterthiourethanstruktur the type mentioned in EP-A 1 640 394.

In the preparation of the lightfast polyurethane and / or polyurea compositions according to the invention, it is also possible to use as isocyanate-reactive compounds B) also low molecular weight, hydroxy- and / or amino-functional components, ie. H. those having a molecular weight range of from 62 to 500, preferably from 62 to 400 are used.

These are, for example, simple mono- or polyhydric alcohols having 2 to 14, preferably 4 to 10 carbon atoms, such as. 1,2-ethanediol, 1,2- and 1,3-propanediol, the isomeric butanediols, pentanediols, hexanediols, heptanediols and octanediols, 1,10-decanediol, 1,2- and 1,4-cyclohexanediol, 1, 4-Cyclohexanedimethanol, 4,4 '- (1-methylethylidene) -bis-cyclohexanol, 1,2,3-propanetriol, 1,1,1-trimethylolethane, 1, 2,6-hexanetriol, 1,1,1-trimethylolpropane, 2 , 2-bis (hydroxymethyl) -1,3-propanediol, bis (2-hydroxyethyl) hydroquinone, 1,2,4- and 1,3,5-trihydroxycyclohexane or 1,3,5-tris (2-hydroxyethyl) - isocyanurate.

Examples of suitable low molecular weight amino-functional compounds are, for example, aliphatic and cycloaliphatic amines and amino alcohols having primary and / or secondary bound amino groups, such as. B. cyclohexylamine, 2-methyl-l, 5-pentanediamine, diethanolamine, monoethanolamine, propylamine, butylamine, dibutylamine, hexylamine, monoisopropanolamine, diisopropanolamine, ethylenediamine, 1,3-diaminopropane, 1, 4-diaminobutane, isophoronediamine, di- ethylenediamine, ethanolamine, aminoethylethanolamine, diaminocyclohexane, hexamethylenediamine, methyliminobispropylamine, iminobispropylamine, bis (aminopropyl) piperazine, aminoethylpiperazine, 1,2-diaminocyclohexane, triethylenetetramine, tetraethylenepentamine, 1,8-p-diaminomethane, bis (4-aminocyclohexyl) methane, Bis (4-amino-3-methylcyclohexyl) methane, bis (4-amino-3,5-dimethylcyclohexyl) methane, bis (4-amino-2,3,5-trimethylcyclohexyl) methane, 1,1-bis ( 4-aminocyclohexyl) propane, 2,2-bis (4-aminocyclohexyl) propane, 1,1-bis (4-aminocyclohexyl) ethane, 1,1-bis (4-aminocyclohexyl) butane, 2,2-bis ( 4-aminocyclohexyl) butane, 1,1-bis (4-amino-3-methylcyclohexyl) ethane, 2,2-bis (4-amino-3-methylcyclohexyl) propane, 1,1-bis (4-amino-3 , 5-dimethylcyclohexyl) ethane, 2,2-bis (4-ami no-3,5-dimethylcyclohexyl) propane, 2,2-bis (4-amino-3,5-dimethylcyclohexyl) butane, 2,4-diaminodicyclohexylmethane, 4-aminocyclohexyl-4-amino-3-methylcyclohexylmethane, 4-amino -3,5-dimethylcyclohexyl-4-amino-3-methylcyclohexylmethane and 2- (4-aminocyclohexyl) -2- (4-amino-3-methylcyclohexyl) methane. Examples of aromatic polyamines, in particular diamines, having molecular weights below 500, which are suitable isocyanate-reactive compounds B) are, for. For example, 1,2- and 1,4-diaminobenzene, 2,4- and 2,6-diaminotoluene, 2,4'- and / or 4,4'-diaminodiphenylmethane, 1,5-diaminonaphthalene, 4.4 ', 4 "-triaminotriphenylmethane, 4,4'-bis (methylamino) -diphenylmethane or 1-methyl-1-methylamino-aminobenzene. 1-Methyl-3,5-diethyl-2,4-diaminobenzene, 1-methyl- 3,5-diethyl-2,6-diaminobenzene, l, 3,5-trimethyl-2,4-diaminobenzene, l, 3,5-triethyl-2,4-diaminobenzene, 3,5,3 ', 5'- Tetraethyl-4,4'-diaminodiphenylmethane, 3,5,3 ', 5'-tetraisopropyl-4,4'-diaminodiphenylmethane, 3,5-diethyl-3', 5'-diisopropyl-4,4'-diaminodiphenylmethane , 3,3'-Diethyl-5,5'-diisopropyl-4,4'-diaminodiphenyhnethane, 1-methyl-2,6-diamino-3-isopropylbenzene, liquid mixtures of Polyphenylpolymethylenpolyaminen, as in a known manner by condensation of aniline and mixtures of such polyamines, for example mixtures of 1-methyl-3,5-diethyl-2,4-diaminobenzene with 1-methyl-3,5-diethyl-2,6-diaminobenzene a G weight ratio of 50:50 to 85:15, preferably from 65:35 to 80:20 particularly mentioned. The use of low molecular weight amino-functional polyethers with molecular weights below 500 is also possible. These are, for example, those having primary and / or secondary, aromatic or aliphatic bound amino groups whose amino groups are optionally attached via urethane or ester groups to the polyether chains and which are accessible by known methods already described above for the preparation of higher molecular weight aminopolyether.

Optionally, sterically hindered aliphatic diamines having two amino groups bound secondarily can also be used as isocyanate-reactive components E), such as, for example, For example, the reaction products of aliphatic and / or cycloaliphatic diamines known from EP-A 0 403 921 with maleic acid or fumaric acid esters, the bisadduct of acrylonitrile to isophoronediamine obtainable in accordance with the teaching of EP-A 1 767 559 or the A 19 701 835 described hydrogenation products of aliphatic and / or cycloaliphatic diamines diamines and ketones, such as. Diisopropyl ketone, accessible Schiff bases.

Preferred reactants B) for the isocyanate-functional starting components A) are the abovementioned polymeric polyetherpolylols, polyesterpolyols and / or aminopolyethers,

as well as said low molecular weight polyhydric amines, in particular sterically hindered aliphatic diamines having two amino groups bound secondarily.

Suitable reactants for the isocyanate-functional starting components A) are also any mixtures of the above-exemplified isocyanate-reactive components B). While using pure hydroxy-functional components B) pure polyurethane compositions and exclusive use of polyamines B) pure polyurea are obtained, can be prepared using amino alcohols or suitable mixtures of hydroxy with amino functional compounds as component B) polyurethane ureas in which the equivalent ratio can be set arbitrarily from urethane to urea groups.

Regardless of the nature of the selected starting materials, the reaction of the polyisocyanate components A) with the isocyanate-reactive components B) is carried out while maintaining an equivalent ratio of isocyanate groups to isocyanate-reactive groups of 0.5: 1 to 2.0: 1, preferably 0.7: 1 to 1.3: 1, more preferably from 0.8: I to 1.2: 1.

In addition to the mentioned starting components A) and B) may optionally further auxiliaries and additives C), such. As catalysts, blowing agents, surfactants, UV stabilizers sators, foam stabilizers, antioxidants, mold release agents, fillers and pigments.

To accelerate the reaction, it is possible, for example, to use customary catalysts known from polyurethane chemistry. Examples may be mentioned here tert. Amines, such as Triethylamine, tributylamine, dimethylbenzylamine, diethylbenzylamine, pyridine, methylpyridine, dicyclohexylmethylamine, dimethylcyclohexylamine, N, N, N ', N'-tetramethyldiaminodiethyl ether, bis (dimethylaminopropyl) urea, N-methyl or N-ethylmorpholine, N-cocomoφholine, N-cyclohexylmorpholine, N, N, N ', N'-tetramethylethylenediamine, N, N, N', N'-tetramethyl-1,3-butanediamine, N, N, N ' , N'-tetramethyl-1,6-hexanediamine, pentamethyldiethylenetriamine, N-methylpiperidine, N-dimethylaminoethylpiperidine, N, N'-dimethylpiperazine, N-methyl-N'-dimethylaminopiperazine, 1,8-diazabicyclo (5.4.0) undecene-7 (DBU), 1,2-dimethylimidazole, 2-methylimidazole, N, N-dimethylimidazole-β-phenylethylamine, 1,4-diazabicyclo- (2,2,2) -octane, bis- (N, N-dimethylaminoethyl) adipate; Alkanolamine compounds, such as. Triethanolamine, triisopropanolamine, N-methyl- and N-ethyl-diethanolamine, dimethylaminoethanol, 2- (N, N-dimethylaminoethoxy) ethanol, N, N ', N "-tris- (dialkylaminoalkyl) hexahydrotriazines, eg N, N' , N "-tris- (dimethylaminopropyl) -s-hexahydrotriazine and / or bis (dimethylaminoethyl) ether; Metal salts, such as. For example, inorganic and / or organic compounds of iron, lead, bismuth, zinc, and / or tin in usual Oxidati- onsstufen the metal, such as iron (II) chloride, iron (m) chloride, zinc chloride, zinc-2 ethyl caproate, stannous octoate, stannous ethylcaproate, stannous (π) palmitate, dibutyltin (rV) dilaurate (DBTL), dibutyldilauryltin mercaptide, or lead octoate; Amidines, such as. B. 2,3-dimethyl-3,4,5,6-tetrahydropyrimidine; Tetraalkylammoniumhydroxide, such as. Tetramethylammonium hydroxide; Alkali hydroxides, such as. For example, sodium hydroxide and alkali metal such as. As sodium methylate and potassium isopropylate, and alkali metal salts of long-chain fatty acids having 10 to 20 carbon atoms and optionally pendant OH groups. Preferred catalysts C) to be used are tertiary amines and tin compounds of the type mentioned.

The catalysts mentioned by way of example can be used singly or in the form of any mixtures with one another in the preparation of the lightfast polyurethane and / or polyurea compositions according to the invention and optionally in amounts of 0.01 to 5.0% by weight, preferably 0.1 to 2 wt .-%, calculated as the total amount of catalysts used based on the total amount of the starting compounds used, for use.

The novel process preferably produces compact molded parts. By adding suitable blowing agents but also foamed moldings can be obtained. Suitable blowing agents suitable for this purpose are, for example, volatile organic substances, such as, for example, acetone. clay, ethyl acetate, halogen-substituted alkanes, such as methylene chloride, chloroform, ethylidene chloride, vinylidene chloride, monofluorotrichloromethane, chlorotrifluoromethane or dichlorodifluoromethane, butane, hexane, heptane or diethyl ether and / or dissolved inert gases, such as nitrogen, air or carbon dioxide. As a chemical blowing agent C), ie blowing agents which form gaseous products due to a reaction, for example with isocyanate groups, for example, water, water containing hydration, carboxylic acids, tertiary alcohols, eg. As t-butanol, carbamates, for example, in EP-A 1 000 955, in particular on pages 2, lines 5 to 31 and page 3, lines 21 to 42 described carbamates, carbonates, eg. As ammonium carbonate and / or ammonium bicarbonate and / or Guanidincarbamat into consideration. A blowing effect can also by adding at temperatures above room temperature with elimination of gases, such as nitrogen, decomposing compounds, eg. As azo compounds such as azodicarbonamide or Azoisobuttersäurenitril be achieved. Further examples of blowing agents as well as details on the use of blowing agents are in Kunststoff-Handbuch, Volume VII, published by Vieweg and Hochtlen, Carl Hanser Verlag, Munich 1966, eg on pages 108 and 109, 453-455 and 507-510 described.

According to the invention, surface-active additives C) can also be used as emulsifiers and foam stabilizers. Suitable emulsifiers are, for example, the sodium salts of castor oil sulfonates or fatty acids, salts of fatty acids with amines, such as. As diethylamine or diethanolamine stearic acid. Also alkali or ammonium salts of sulfonic acids, such. B. of dodecylbenzenesulfonic acids, fatty acids, such as. As ricinoleic acid, or polymeric fatty acids, or ethoxylated nonylphenol can be used as surface-active additives.

Suitable foam stabilizers are, in particular, the known, preferably water-soluble, polyether siloxanes, as described, for example, in US Pat. No. 2,834,748, DE-A 1 012 602 and DE-A 1 719 238. The allophanate-branched polysiloxane-polyoxyalkylene copolymers obtainable according to DE-A 2 558 523 are also suitable foam stabilizers.

The abovementioned emulsifiers and stabilizers which may optionally be used in the process according to the invention can be used either individually or in any desired combination with one another.

The bodies obtained from the polyurethane and / or polyurea compositions which can be prepared or used according to the invention are already distinguished as such, ie without the addition of appropriate stabilizers, by a very good lightfastness. Nevertheless, in their manufacture if appropriate, UV stabilizers (light stabilizers) or antioxidants of the known type are used as further auxiliaries and additives C).

Suitable UV stabilizers C) are, for example, piperidine derivatives, such as. For example, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 4-benzoyloxy-l, 2,2,6,6-pentamethylpiperidine, bis (2,2,6,6-tetra methyl-4-piperidyl ) sebacate, bis (l, 2,2,6,6-pentamethyl-l-4-piperidinyl) sebacate, bis (2,2,6,6-tetramethyl-4-piperidyl) suberate or bis - (2,2,6,6-tetramethyl-4-piperidyl) -dodecandioat, Benzophen- onderivate, such as. B. 2,4-dihydroxy, 2-hydroxy-4-methoxy, 2-hydroxy-4-octoxy, 2-hydroxy-4-dodecyloxy or 2,2'-dihydroxy-4-dodecyloxy-benzophenone, benzotriazole derivatives, such as B. 2- (2'-hydroxy-3 ', 5'-di-tert-amylphenyl) benzotriazole, oxalanilides, such as. B. 2-ethyl-2'-ethoxy or 4-methyl-4'-methoxyoxalanilid, salicylic acid esters, such as. As Salicylsäurephenylester, salicylic acid-4-tert-butylphenyl ester and salicylic acid 4-tert-octylphenylester, Zimtsäureesterderivate, such as. B. α-cyano-.beta.-methyl-4-methoxycinnamate, α-cyano-.beta.-methyl-4-methoxycinnamate, α-cyano-.beta.-phenylcinnamate and α-cyano-.beta.-phenylcinnamic acid isooctylester, or malonate derivatives, such as. B. 4-Methoxy-benzylidenmalonsäuredimethylester, 4-Methoxybenzyli- denmalonsäurediethylester and 4-Butoxy-benzylidenmalonsäuredimethylester. These light stabilizers can be used both individually and in any combination with each other.

Suitable antioxidants C) are, for example, the known sterically hindered phenols, such as. As 2,6-di-tert-butyl-4-methylphenol (ionol), pentaerythritol tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate), octadecyl-S- ^ S-di-tert-butyl-hydroxyphenyi-propionate, triethylene glycol bis (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate, 2,2'-thio-bis (4-methyl-6- tert-butylphenol), 2,2'-thiodiethyl-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], which are used both individually and in any combination with one another.

Further auxiliary agents and additives C) which may be used are, for example, cell regulators of the type known per se, such as, for example, cell regulators. Paraffins or fatty alcohols, the known flame retardants, e.g. Tris-chloroethyl phosphate, ammonium phosphate or polyphosphate, fillers such. As barium sulfate, diatomaceous earth, soot, whiting or reinforcing acting glass fibers. Finally, in the case of the process according to the invention, it is optionally also possible to use the per se known internal mold release agents dyes, pigments, hydrolysis protectants, fungistatic and bacteriostatic substances.

Said auxiliaries and additives C), which may be used, may be admixed with both the polyisocyanate component A) and / or the isocyanate-reactive component B). To prepare the light-fast bodies of polyurethane and / or polyurea compositions according to the invention, the polyisocyanate component A) is reacted with the isocyanate-reactive component B), optionally with the concomitant use of the abovementioned auxiliaries and additives C), in solvent-free form in the abovementioned NCO / OH ratio mixed with the aid of suitable mixing equipment and by any methods, in open or closed forms, for example by simple pouring by hand, but preferably by means of suitable machines, such as. As the usual in polyurethane technology low pressure or high pressure machines or by the RIM process, at a temperature of up to 160 ⁰ C, preferably from 20 to 14O ⁰ C, more preferably from 40 to 100 ⁰ C, and optionally under an elevated Pressure of up to 300 bar, preferably cured to 100 bar, more preferably up to 40 bar.

In this case, the starting components A) and B) to reduce the viscosities optionally to a temperature of up to 120 ° C, preferably up to 100 ⁰ C, more preferably up to 90 ⁰ C, preheated and optionally degassed by applying a vacuum. In general, the polyols which are thus prepared from the polycluels prepared or usable in accordance with the invention can be used as additives xcu ^ lx xvux ljl / X / _fuii, jLxcivxx a time of 2 to 60 min, be removed from the mold. Optionally, a post-curing at a temperature of 50 to 100 ⁰ C, preferably at 60 to 90 ⁰ C, join.

In this way one obtains from these polyurethane and / or polyurea masses compact or foamed, light- and weather-resistant, hard Köφer, characterized by excellent optical properties, high resistance to solvents and chemicals and an excellent heat distortion even at higher temperatures For example, 90 ⁰ C distinguish.

These new polyurethane and / or Polyharnstoffköφer are suitable for a variety of different applications, such as for the production of or as glass replacement discs, such. As sunroofs, front, rear or side windows in vehicle or aircraft, as safety glass or for the production of spectacle lenses and optical lenses. Because of their exceptionally high lightfastness, in particular also with hot exposure, in combination with the mentioned high heat resistance, the polyurethane and / or polyurea compositions obtainable or usable according to the invention are also very particularly suitable for producing dimensionally stable optical components, for example lenses or collectors , as they are used as intent optics in LED lights or automotive headlights.

In addition, they are also excellent for the transparent encapsulation of optical, electronic or optoelectronic components, such. As of solar modules or light emitting diodes, wherein the casting in the latter can also be formed lens-shaped. In addition, the polyurethane and / or polyurea compositions which can be used according to the invention in combination with suitable blowing agents also allow the production of bodies from yellowing-resistant or hard integral foams resistant to yellowing.

Examples

All percentages are by weight unless otherwise stated.

The NCO contents were determined titrimetrically in accordance with DIN EN ISO 11909.

OH numbers were determined titrimetrically in accordance with DIN 53240 T.2, acid numbers according to DIN 3682.

The residual monomer contents were measured according to DIN EN ISO 10283 by gas chromatography with an internal standard.

All viscosity measurements were carried out using a Physica MCR 51 Rheometer from Anton Paar Germany GmbH (DE) in accordance with DIN EN ISO 3219. The Hazen color number was measured spectrophotometrically according to DIN EN 1557 using a LICO 400 spectrophotometer from Lange, DE.

The glass transition temperature Tg was determined by DSC (differential scanning calorimetry) with a Mettler DSC 12E (Mettler Toledo GmbH, Giessen, Germany) at a heating rate of 10 ° C / min. Shore hardnesses were measured according to DIN 53505 using a Shore hardness tester Zwick 3100 (Zwick, DE).

CIE-Lab values (DIN 6174), Yellowness Index (ASTM E 313) and transmission measurements were carried out with a Lambda 900 spectrorphotometer with integration sphere (150 mm) from Perkin-Elmer, USA (07diffus, reference: air T = 100%). The xenon exposures were carried out according to DIN EN ISO 11431 in a Suntest CPS (Atlas, USA) with Suprax daylight filter (UV edge at 290 nm, black panel temperature (STT) = 48 ^° C.). As a measure of hue changes, CIE Lab and ΔE values were determined.

starting compounds

Polyisocvanate al-D

Isocyanurate group-containing HDI polyisocyanate, prepared on the basis of Example 11 of EP-A 330 966, with the change that 2-ethylhexanol instead of 2-ethyl-l, 3-hexanediol was used as the catalyst solvent.

NCO content: 22.9%

NCO functionality: 3.2 Monomeric HDI: 0.1%

Viscosity (23 ° C): 1,200 mPas

Polyisocvanate al-ID isocyanurate- and iminoxadiazinedione-containing HDI polyisocyanate, prepared on the basis of Example 4 of EP-A 0 962 455, by trimerization of HDI using a 50% strength solution of tetrabutylphosphonium hydrogen difluoride in isopropanol / methanol (2: 1) as catalyst, reaction stop at an NCO content of the crude mixture of 43% by addition of dibutyl phosphate and subsequent separation of the unreacted HDI by thin-layer distillation at a temperature of 130 ⁰ C and a pressure of 0.2 mbar.

NCO content: 23.4%

NCO functionality: 3.2

Monomeric HDI: 0.2%

Viscosity (23 ° C): 700 mPas

Polvisocvanat al-HI)

Isocyanurate and allophanate-containing HDI polyisocyanate prepared analogously to Example 4 of EP-A 0 496 208.

NCO content: 20.0%

NCO functionality: 2.5 ^•

Monomeric HDI: 0.1%

Viscosity (23 ^° C.): 450 mPas

Polvisocvanat al - IV)

Isocyanurate and uretdione-containing HDI polyisocyanate prepared analogously to Example 1 (comparative polyisocyanate) of EP-B 1 174 428. NCO content: 21.6%

NCO functionality: 2,4

Monomeric HDI: 0.2%

Viscosity (23 ° C): 160 mPas

Polvisocvanat a2 - T)

Isophorone diisocyanate (IPDI) is trimerized according to Example 2 of EP-AO 003 765 to an NCO content of 31.1% and the excess IPDI by thin film distillation at 170 ° C / 0, l mbar away. A Isocyanuratpolyisocyanat obtained as a nearly colorless solid resin having a melting range of 100 to 110 ⁰ C.

NCO content: 16.4 °,

NCO functionality: 3.3

Monomeric IPDI: 0.2%

Polyisocyanate a2 - IT)

A mixture of an isocyanurate-containing polyisocyanate based on 4,4'-diisocyanatodicyclohexylmethane with an isocyanurate polyisocyanate based on HDI, prepared as described in EP-A 1 484 350 (polyisocyanate A2-H), with a melting range of 75 to 85.degree.

NCO content: 15.1%

NCO functionality: 3.5

Monomeric diisocyanates: 0.2%

Production of the Polvovan Vanadium Components A)

The solid polyisocyanates of type a2) based on cycloaliphatic diisocyanates were coarsely crushed and placed in a reaction vessel at room temperature together with the liquid HDI polyisocyanate type al) under N 2 atmosphere. To dissolve the solid resin and homogenize the mixture was heated to 100 - 140 ⁰ C and stirred until a nearly clear solution was obtained. It was then cooled to 50 ⁰ C and filtered through a 200 mu filter. Table 1 below shows compositions (parts by weight) and characteristics of the polyisocyanates thus prepared.

Table 1:

Hydroxyfunctional reactant Bl)

Component B 1-a)

3112 g (34.6 mol) of 1,3-butanediol, 1863 g (17.9 mol) of neopentyl glycol, 2568 g (19.2 mol) of trimethylolpropane and 6706 g (40.4 mol) of isophthalic acid were combined in a reactor , which was equipped with stirrer, heating, automatic temperature control, nitrogen inlet, column, water and receiver, weighed and heated with stirring and passing nitrogen to 200 ⁰ C that the top temperature at the column 102 ⁰ C was not exceeded. After completion of the distillation of the theoretically calculated amount of water of reaction (1649 g), the water was replaced by a distillation bridge and the reaction mixture at 200 ⁰ C until the product had an acid number of <5 mg KOH / g. A high-viscosity polyester polyol was obtained at room temperature with the following characteristics:

Flow time (23 ° C): 29 s as 55% solution in MPA (ISO 2431)

OH number: 335 mg KOH / g

Acid value: 4.7 mg KOH / g Color number (APHA): 27 Hazen

Average molecular weight: 435 g / mol (calculated from OH number)

Component B 1 -b)

4034 g (35.4 mol) of ε-caprolactone, 9466 g (70.6 mol) of trimethylolpropane and 6,75g tin (IT) -2-ethyl hexanoate were mixed under dry nitrogen and heated to 160 ⁰ C for 4 hours. After cooling to room temperature was a liquid polyester diol with the following characteristics.

Viscosity (23 ^° C.): 4600 mPas

OH number: 886 mg KOH / g

Acid value: 0.4 mg KOH / g

Color number (APHA): 42 Hazen Average molecular weight: 190 g / mol (calculated from OH number)

Preparation of the Hydroxy-Functional Reactant Bl)

6300 g of component Bl-a), 6300 g of component Bl-b) and 1400 g of dipropylene glycol were stirred in a stirred tank for 1 hour at 60 ⁰ C with each other. The hydroxy reactant Bl) was obtained with the following characteristics: (23 ⁰ C) Viscosity: 19900 mPas OH number: 628 mg KOH / g

Acid value: 2.2 mg KOH / g

Color Number (APHA): 64 Hazen

Average molecular weight: 243 g / mol (calculated from OH number)

Hydrofunctional Reactant B2)

Component B2-a)

According to the process described in the preparation of the hydroxy-functional reactant Bl) for components Bl-a), from 3755 g (41.7 mol) of 1,3-butanediol, 2249 g (21.6 mol) of neopentyl glycol, 3099 g (23, 1 mol) of trimethylolpropane and 5386 g (55.0 mol) of maleic anhydride is a polyester polyol which is highly viscous at room temperature and has the following characteristics:

Flow time (23 ° C): 22 s as 55% solution in MPA (ISO 2431)

OH number: 331 mg KOH / g

Acid value: 4.7 mg KOH / g Color number (APHA): 23 Hazen

Average molecular weight: 465 g / mol (calculated from OH number)

Preparation of the hydroxy-functional reaction partner B2)

6750 g of component B2-a), 6750 g of the caprolactone polyester described in the production of the hydroxy reactant Bl) as the component Bl-b) and 1500 g dipropylene 1 hour at 60 ⁰ C were stirred glycol with one another in a stirred tank. The hydroxy-functional reaction partner B2) was obtained with the following characteristics:

Viscosity (23 ^° C.): 8100 mPas

OH number: 616 mg KOH / g

Acid value: 2.3 mg KOH / g Color number (APHA): 64 Hazen

Average molecular weight: 250 g / mol (calculated from OH number)

Hydroxyfunctional reaction partner B3)

Polyetherpolyolgemisch, consisting of equal parts by weight of a tri-methylol propane started polypropylene oxide polyether having an OH number of 1029 mg KOH / g and a viscosity (23 ° C) of 8100 mPas and a trimethylolpropane started ethylene oxide polyether having an OH number of 550 mg KOH / g and a viscosity (23 ⁰ C) of 505 mPas.

Examples 1 to 7 (Production of potting compounds)

Polyisocyanate components A) and polyol components B), if appropriate with the concomitant use of DBTL as catalyst, in the combinations and proportions (parts by weight) indicated in Table 2, in each case corresponding to an equivalent ratio of isocyanate groups to hydroxyl groups, were used to prepare potting compounds 1: 1, homogenized for 1 min at 3500 rpm using a DAC 150 FVZ speed mixer (Hauschild, DE) and then poured by hand into open, unheated polypropylene molds. After curing for 30 minutes at room temperature or at 70 ^° C. in a drying cabinet, the test specimens (diameter 50 mm, height 5 mm) were removed from the mold. After a post-curing time of 24 hours, the test specimens were tested for their mechanical and optical properties. For a quick evaluation of the heat resistance, the Shore hardness of a sample heated to 80 ^° C. was measured and the difference to the Shore hardness of the same sample measured at room temperature was calculated. The test results can also be found in Table 2. As the examples show, the polyisocyanate components used according to the invention as crosslinkers for casting compounds AI to AV both in combination with polyester polyols based on aromatic carboxylic acids (Examples 1 to 5) and in combination with aliphatic polyester polyols (Example 6) and polyether polyols (Example 7) very hard casting compounds with excellent heat resistance and high optical transparency. Example 6 and the facts che that the specimen obtained in Example 7 shows an only slightly increased yellow value of 2.2 after one week of storage at 90 ⁰ C, disprove the teachings of the EP-A 1484350, according to which the combination of such polyisocyanates with aliphatic polyester polyols or polyether polyols generally leads to turbid or non-yellowing resistant polyurethanes.

Table 2:

Example 8)

The potting compound from Example 1 was poured into a heatable mold (195 × 290 × 4 mm) with the aid of a laboratory dosing device under the conditions given in Table 3.

Table 3: Processing parameters

a ⁾ Processing temperature in each case 65 ° C

Specimens thus obtained were cut out and subjected to further mechanical and thermal tests, the results of which are shown in Tables 4 and 5.

Table 4: Mechanical properties

Table 5: Thermal properties

Example 9)

A test specimen prepared according to Example 1 was exposed to a white LED exposure at a sample temperature of 90 ^° C. at a distance of 2 mm. Table 6 shows the evolution of transmission, hue (CIE-Lab values) and yellowness index (YT) over the exposure period. In particular, the high and unchanged in time transparency (~ 90% transmission) and the low yellowing, demonstrate the excellent suitability of erfϊndungsgemis- sen polyisocyanates for the production of elastic casting compounds for the encapsulation of light emitting diodes.

Table 6:

Example 10

100 parts by weight of polyol B3), 1.0 part by weight of water, 0.5 part by weight of DBTL and 0.5 part by weight of DBU were mixed with the aid of a SpeedMixer DAC 150 FVZ (Hauschild, DE). Homogenized at 3500 rpm for 1 min. The catalyzed polyol mixture so obtained was mixed with 50 parts by weight of the polyisocyanate component A-IV, corresponding to an equivalent ratio of isocyanate to hydroxyl groups of natgruppen 1.05: 1 tempered, device by means of a laboratory Zweikomponentendosiermisch- in a 70 ⁰ C closed aluminum mold measuring 10 x 250 x 350 mm, whose inner walls were pretreated with a non-silicone-based release agent, Acmos 30-2411 (Acmos Chemie KG, DE), and registered to a density of 0.6 g / cm ³ compacted. The free density of the foam was 0.220 g / cm ³ . The reaction mixture showed the following processing times: starting time = 20 s, setting time = 50 s. After 10 minutes, the part was demolded and stored at 23 ° C for a further 24 h.

This gave an aliphatic integral foam with a compact skin that was closed on all sides and had an overall density of 0.608 g / cm ³ , a Shore D hardness of 60 and a Tg of 92 ° C. The molded article showed no softening after storage for one hour at 90 ° C.

Claims

claims

1. Use of solvent-free polyisocyanate A) a viscosity of 2,000 to 100,000 mPas at 23 ° C, a content of isocyanate groups of 13 to 23 wt .-% and an average isocyanate functionality of at least 2.5, to 30 to 95 wt. % of at least one polyisocyanate a-1) based on hexamethylene diisocyanate with an NCO

Content of 16 to 24 wt .-% and 5 to 70 wt .-% of at least one polyisocyanate a-2) based on cycloaliphatic diisocyanates having an NCO content of 10 to 22% by weight, for the production of light-density compact or foamed polyurethane and / or polyurea body.

2. Use according to claim 1, characterized in that the Polyisocyanatkomponen te A) at 23 ° C has a viscosity of 6,000 to 60,000 mPas, a content of isocyanate groups of 15 to 22 wt .-% and an average isocyanate functionality of 2, 8 to 5.0.

3. Use according to claim 1, characterized in that as polyisocyanates a-1) lophanate -, biuret, isocyanurate, iminooxadiazinedione, oxadiazinetrione, uretdione and / or urethane groups containing derivatives of KexameLhyleiidiisöcyanats be used, which at 23 ° C have a viscosity of 80 to 4000 mPas, a content of isocyanate groups of 16 to 24.5 wt .-% and an average isocyanate functionality of at least 2.0.

4. Use according to claim 1, characterized in that as polyisocyanates a-2) isocyanurate-containing polyisocyanates based on isophorone diisocyanate and / or

2,4'- and 4,4'-diisocyanatodicyclohexylmethane are used, which have a content of isocyanate groups of 13 to 19 wt .-%.

5. Use according to claim 1, characterized in that the bodies are glass substitutes

6. Use according to claim 1, characterized in that it is in the bodies to discs in the automotive or aircraft.

7. Use according to claim 6, characterized in that it is at the windows to sunroofs, front, rear or side windows in the automotive or aircraft.

Use according to claim 1, characterized in that the bodies are safety glass.

9. Use according to claim 1, characterized in that the bodies are optical lenses or spectacle lenses.

10. Use according to claim 1, characterized in that the bodies are transparent encapsulated optical, optoelectronic or electronic components.

11. Use according to claim 10, characterized in that it is the solar modules in the components.

12. Use according to claim 10, characterized in that it is the LEDs are light-emitting diodes.

Use according to claim 1, characterized in that the bodies are hard or semi-rigid integral foams

14. A process for producing light-fast polyurethane and / or polyurea body by solvent-free reaction

A) a Poiyisocyaiialkυmponeirie a viscosity of 2,000 to 100,000 mPas at 23 ° C, a content of isocyanate groups of 13 to 23 wt .-% and an average isocyanate functionality of at least 2.5, and to 30 to 95 wt. -% of at least one polyisocyanate a-1) based on hexamethylene diisocyanate having an NCO content of 16 to 24 wt .-% and at 5 to 70 wt .-% of at least one polyisocyanate a-2) based on cycloaliphatic diisocyanates with a NCO content of 10 to 22 wt .-%, consists, with

B) to isocyanate-reactive reactants having an average functionality of 2.0 to 6.0 and optionally with concomitant use

C) further auxiliaries and additives, while maintaining an equivalent ratio of isocyanate groups to isocyanate-reactive groups of 0.5: 1 to 2.0: 1.

15. The method according to claim 14, characterized in that as component B) hydroxy, amino and / or mercapto-functional compounds having an average molecular weight of 62 to 12,000 are used.

16. The method according to claim 14, characterized in that as component B) polyether polyols, Polyesteφolyole, polycarbonate polyols and / or aminopolyethers having an average molecular weight of 500 to 12,000, polythioether thiols, polyester thiols and / or low molecular weight hydroxy and / or amino-functional components of a middle MoIe- culargewichtes 62 to 500 are used.

17. The method according to claim 14, characterized in that water is used as the blowing agent as component C).

18. The method according to claim 14, characterized in that the reaction of the reactants is carried out at a temperature of up to 160 ⁰ C and a pressure of up to 300 bar.