Storage-stable, mould release agents-containing polyol compositions.

0001The invention relates to polyol mixtures which contain internal mold release agent mixtures and optionally further auxiliaries.

0002The production of hard, semi-hard and flexible polyurethane materials is often carried out in such a way that a polyol mixture is mixed with polyisocyanates by machine and injected into a mold in which the reaction mixture which is reacting is then cured, possibly with the formation of layers of different densities. The mold can be made of various materials (such as steel, aluminum or epoxy resin) and can be heated or unheated.

0003For better demoldability of the workpiece formed in this way from the reaction mixture, so-called external release agents or release lacquers which are injected into the mold or so-called internal release agents which are incorporated into the reaction mixture and without the use of external release agents to ensure good demoldability of the formed workpiece (molded part ) to lead. Such internal release agents can be added to the isocyanate component of the reaction mixture or preferably the polyol component of the reaction mixture or both components before they are combined in the mixing device.

0004Internal release agents are often products that contain aliphatic paraffin chains, which should mostly contain more than 10 carbon atoms. Reaction products or derivatives of long-chain fatty acids, in particular natural fatty acids, such as oleic acid, tall oil fatty acid, stearic acid, palm kernel fatty acids, trans fatty acids, ricinoleic acids, linoleic acids, erucic acids or mixtures thereof, are preferably used.

0005Descendants or reaction products of such fatty acids that can be used in principle are their hydrogenation or reduction products, their esterification or amidation products, salts, urethanes or esters of such esterification or amidation products, amine salts of such fatty acids or addition products, for example on carbodiimides or in the context of Passerini or Ugi - multi-center reactions.

0006In the course of time, two types of internal release agents have proven to be particularly effective, namely the types which contain NH functions, be it through amide or urethane bonds in the molecule or those types which contain amine salt functions, the latter possibly also themselves May have amide functions. Both basic types can also have ester groups.

0007Of the salt-like types, there may be mentioned, for example, the oleic acid salt of the amide from 1 mol of 1,3-N-dimethylpropylenediamine and oleic acid or of the ester from 1 mol of N-dimethylethanolamine and oleic acid. Of the -NH functions, non-salt-like types of internal release agents are, for example, the reaction product of diisocyanatodiphenylmethane types (ie polyisocyanates) with the ester from, for example 1 Mol called pentaerythritol and 2 to 3 moles of oleic acid, or the oleic acid amide from 1 mole of oleic acid and the oleic acid ester of ethanolamine.

0008Urethane or ester group-containing, non-salt-like release agents, like the release agents containing salt groups, can be used particularly well as internal release agents.

0009The polyol mixtures used for the production of molded parts from polyol and polyisocyanate mixtures mentioned at the outset often contain short-chain polyols, ie based on polyalcohols and / or (poly) amines by alkoxylation up to OH numbers over 700 polyols, and medium-chain polyols, ie equally , but through extensive alkoxylation up to OH numbers between approx. 100 and 700, converted products, and on the same principle in principle but up to OH numbers between 8 and 100 converted products (so-called long-chain polyols).

0010Of course, short-chain, medium-chain or long-chain polyols of a different type of preparation which are characterized by the OH number ranges mentioned are also suitable, be they polyesters, polyamides, polyurethanes, non-modified, primarily accessible polyols, such as glycerol, sugar products, formoses and others , or so-called polymer polyols, filler-containing polyols, So-called PHD polyols or other polyisocyanate reaction products in stable dispersion containing polyols and polyol mixtures.

0011In addition, such polyol mixtures often contain further special pore stabilizers, if appropriate oxidation or radiation stabilizers, colorants, fragrances or other active substances, and small amounts of water and, if appropriate, additional blowing agents.

0012DE-OS 1 953 637 discloses a process for the production of foams by foaming a reaction mixture of polyisocyanates, compounds with reactive hydrogen atoms, water and / or organic blowing agents and additives in closed forms. Salts of aliphatic carboxylic acids and primary amines or amines and / or ester groups containing amines having at least 25 aliphatic carbon atoms are used as additives.

0013DE-OS 2 307 589 describes a process for the production of foams based on polyisocyanates in which, with the use of reaction products of fatty acid esters and polyisocyanates and, if appropriate, further release agents, such as oleic acid or tall oil fatty acid salts of the amide group-containing amine, which can be obtained by reacting N -Dimethylaminopropylamine with oleic acid or tall oil fatty acid is available, the foams are made in closed molds.

0014In the process according to DE-OS 2 121 670, the foam molded parts are produced using mixtures of at least two of the following components:<ul id="ul0001" list-style="none"><li>a) salts of aliphatic carboxylic acids and amines optionally having amide and / or ester groups,</li><li>b) esters of mono- and / or polyfunctional carboxylic acids having COOH and / or OH groups,</li><li>c) natural and / or synthetic oils, fats or waxes.</li></ul>

0015It has now been shown that in particular the highly effective internal release agents of the type described above, for example the release agents containing urethane-NH groups, when they are added to the polyol mixtures in the larger amounts necessary for good demolding, tend to result in unstable mixtures and "swim out".

0016It is also known to use mixtures of a plurality of release agents as an internal release agent in the production of molded parts, if appropriate even distributed in the polyol and polyisocyanate phase, if particularly good release effects are to be achieved.

0017All systems, however, have the disadvantage that they do not contain stable, ie storable preparations from the polyol mixtures customary in the production of molded parts and those which are often largely incompatible with these polyol mixtures, which can be stored for longer periods, as is customary in the transport and storage of polyurethane raw materials can produce internal release agents, especially if the release agents are added in amounts above 5%.

0018It was therefore an object to provide polyol mixtures containing internal release agents which are stable, ie can be stored for a long time, and have a good release action.

0019This object could be achieved with the mixtures of polyol mixtures and release agent mixtures according to the invention.

0020The invention relates to internal mold release agent mixtures containing polyol mixtures, which are characterized in that they essentially 55 to 95% by weight of a polyol mixture a) consisting of<ul id="ul0002" list-style="none"><li>a1) 30 to 70 wt .-% of a polyol with an OH number> 700 and</li><li>a2) 70 to 30% by weight of a polyol with an OH number ≦ 700</li></ul> and 5 to 45% by weight of a mold release agent mixture b) consisting of<ul id="ul0003" list-style="none"><li>b1) 60 to 95% by weight of salt-like release agents and</li><li>b2) 5 to 40 wt .-% release agents with amide or urethane-NH functions without salt character</li></ul> and optionally contain other aids c).

0021The polyol mixtures a) preferably consist of<ul id="ul0004" list-style="none"><li>a1) 40 to 65 wt .-% of a polyol with an OH number> 700 and</li><li>a2) 60 to 35% by weight of a polyol with an OH number ≦ 700</li></ul> and the mold release agent mixtures b)<ul id="ul0005" list-style="none"><li>b1) 70 to 90 wt .-% salt-like release agents and</li><li>b2) 10 to 30 wt .-% release agents with amide or urethane-NH functions without salt character.</li></ul>

0022The polyol mixtures preferably contain 70 to 88% by weight of polyol mixtures a) and 12 to 30% by weight of internal mold release agent mixtures b) and, if appropriate, further auxiliaries c).

0023Water, stabilizers, catalysts, etc. are preferably used as auxiliary means c).

0024The polyol mixtures according to the invention containing inner mold release agent mixtures are used together with polyisocyanates in the production of polyurethane plastics in reaction injection molding / molded part production processes.

0025Advantageously, the stable mixtures according to the invention contain the internal release agents in larger amounts and additionally stabilizers and other additives.

0026The polyol mixtures with OH numbers ≦ 700 can contain so-called medium-chain polyols and / or so-called long-chain polyols.

0027The release agent mixture is added to the polyol mixture, which is to serve as the reaction component with the polyisocyanate component in the production of the molded part by mixing these two components, in an amount of 5 to 45% by weight, preferably 12 to 30% by weight, before mixing with the isocyanate component. based on the total mixture added.

0028It has been shown that only in the area according to the invention of the parameter field consisting of internal release agents containing salt groups and internal release agents containing amide or urethane-NH functions without salt functions and the mixtures of polyols of short-chain and longer-chain type used a stable, ie it is not possible to produce a mixture which tends to separate coherent, different-phase mixtures, which has reproducibly good separation effects and does not give rise to any disruption to the production of molded parts and to no deterioration in the properties of the molded parts obtained.

0029The polyol mixture according to the invention can be a stable, clear solution but also a stable dispersion, emulsion or turbidity which does not tend to separate.

0030The polyol mixtures advantageously contain both neutral and basic polyol types.

0031The polyol component a2) preferably consists of 25 to 75% by weight of polyols with OH numbers between 100 and 700 and 25 to 75% by weight of polyols with OH numbers below 100.

0032The types of internal release agents containing salt-like functions particularly preferably additionally contain -CONH or -COOR functions and represent salts of fatty acids with more than 10 C atoms, while the internal release agents of the type to be combined with this type of internal release agents without have salt-like functions -CONH functions and have one or more residues -COR in the molecule, the group -COR being derived from fatty acids with more than 10 C atoms.

0033The above-mentioned fatty acids with more than 10 carbon atoms are advantageously liquid, in particular natural, fatty acids at room temperature.

0034The aforementioned polyol mixtures are preferably polyether polyols which are produced according to the prior art by alkoxylation of acidic, neutral or basic starters with ethylene oxide and / or propylene oxide and in which the alkoxylating agents are incorporated in a mixture in blocks or in alternating arrangements.

0035The types of internal release agents with salt character to be used according to the invention are preferably fatty acid salts of the fatty acid amides from fatty acid and N-dimethyl-propylenediamine-1,3 and the types of internal release agents without salt character to be used are reaction products of polyisocyanates with the esters 1 mole of pentaerythritol and 3 moles of fatty acid, oleic acid and / or tall oil fatty acid being used as the fatty acid.

0036The conventional construction of the polyol components used for the production of molded parts and the polyisocyanate components correspond to the prior art and are familiar to the person skilled in the art. In principle, this also applies to the individual types of internal release agents used according to the invention, be they those with a salt-like character or those that have no salt-like character.

0037The person skilled in the art is familiar with the corresponding production or mixing techniques and the use of further, conventional auxiliaries and additives.

0038In addition to the types already mentioned, the salt-like release agents would also include, for example, salts from fatty amines, such as octylamine, oleylamine, dodecylamine, amines obtainable by reducing fatty acid amides or from alkoxylation of ammonia or prim. and / or sec. basic amine derivatives accessible to aliphatic or aromatic amines, fatty acid esters of such alkoxylation products, for example, N-dimethylethanolamine, N-methyldiethanolamine or tetraethoxy or Tetrapropoxyethylene diamine or amidamines, such as amidamines from fatty acids and N-methyldiethylene triamine or N-dimethylethylene diamine or triethylene tetramine, where oleic acid or tall oil fatty acids, trans fatty acids and other fatty acids which are liquid at room temperature are preferably used for salt formation.

0039In addition to the types already mentioned, the non-salt-like release agents to be combined with the above would also include: e.g. esters from fatty alcohols and fatty acids, fatty acid esters of mono- and polyhydric alcohols, for example also fatty acid glycerides, esters from fatty acids and amino alcohols, and the like are described above, or amides or amide esters, for example from oleic acid and amino alcohols such as ethanolamine, or urethanes from partial fatty acid esters of polyfunctional alcohols and polyisocyanates or esters from alcohols and amino acids amidated with fatty acids. The non-salt-like release agent types have at least one -CONH function in the molecule, such as in amides or urethanes.

0040The advantage of the mixtures of polyols and release agent mixtures according to the invention, even in relatively large amounts, is that they lead to technically usable moldings within the compositions according to the invention and at the same time ensure their correct demolding from the technically customary molds over almost unlimited production sequences, the polyol mixture according to the invention not tending to float out of the mixed-in release agents even over a long transport and storage time, but instead represents a segregation-stable mixture in the form of a solution or dispersion.

0041This leads to an improved production possibility for the molded parts produced by reaction injection molding compared to the prior art, since no storage-stable polyol mixtures were available to date or the known polyol mixtures led to segregation. As a result, the storage tanks had to be stirred and only very short storage and transport times were permitted.

0042The invention is illustrated by the following examples.

Examples

0043In experiments, the stability behavior of the polyol mixtures according to the invention is examined after storage for 148 hours at room temperature. The parts and percentages given relate to the weight, unless stated otherwise.

0044After mixing the components with a high-speed mixer, they were stored in glass bottles with a square cross-section. The phase relationships were assessed qualitatively in the transmitted light of a light bulb with the eye.

0045The following classification was made: <tables id="tabl0001" num="0001"><table frame="all"><tgroup cols="3" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="52.50mm" /><colspec colnum="2" colname="col2" colwidth="52.50mm" /><colspec colnum="3" colname="col3" colwidth="52.50mm" /><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">class 1</entry><entry namest="col2" nameend="col2" align="left">clear, single phase</entry><entry namest="col3" nameend="col3" align="left">stable</entry></row><row><entry namest="col1" nameend="col1" align="left">2nd grade</entry><entry namest="col2" nameend="col2" align="left">homogeneous, slight turbidity</entry><entry namest="col3" nameend="col3" align="left">stable</entry></row><row><entry namest="col1" nameend="col1" align="left">Class 3</entry><entry namest="col2" nameend="col2" align="left">homogeneous, stronger turbidity</entry><entry namest="col3" nameend="col3" align="left">stable</entry></row><row><entry namest="col1" nameend="col1" align="left">Class 4</entry><entry namest="col2" nameend="col2" align="left">weak turbidity with little phase separation</entry><entry namest="col3" nameend="col3" align="left">unstable</entry></row><row><entry namest="col1" nameend="col1" align="left">Class 5</entry><entry namest="col2" nameend="col2" align="left">greater turbidity with phase separation</entry><entry namest="col3" nameend="col3" align="left">unstable</entry></row><row rowsep="1"><entry namest="col1" nameend="col1" align="left">Class 6</entry><entry namest="col2" nameend="col2" align="left">Separation into well separated phases</entry><entry namest="col3" nameend="col3" align="left">unstable</entry></row></tbody></tgroup></table></tables>

0046The following were used as salt-like release agents S:<dl id="dl0001"><dt>S₁:</dt><dd>Salt obtained by reacting one mole of 1,3-N-dimethylpropylenediamine with 2 moles of oleic acid in a nitrogen atmosphere. The salt of the oleic acid amide is formed under amidation conditions.</dd><dt>S₂:</dt><dd>Salt obtained by reacting 1 mol of N-methyl-diethanolamine with 3 mol of tall oil fatty acid under esterification conditions. The ester salt is formed.</dd></dl>

0047The following were used as non-salt-like release agents E:<dl id="dl0002"><dt>E₁:</dt><dd>Reaction product prepared at approx. 80 ° C from 2 moles of pentaerythritol-trioleic acid ester and 1 mole of technical diisocyanatodiphenylmethane.</dd><dt>E₂:</dt><dd>Amide ester from 1 mol ethanolamine and 2 mol oleic acid.</dd></dl>

0048The following types were used as polyols D: Short chain polyols<dl id="dl0003"><dt>D₁:</dt><dd>Propoxylation product of trimethylolpropane, OH number 1020</dd><dt>D₂:</dt><dd>Propoxylation product of trimethylolpropane, OH number 860</dd></dl> Medium chain polyols:<dl id="dl0004"><dt>D₃:</dt><dd>Propoxylation product of ethylenediamine, OH number 640</dd><dt>D₄:</dt><dd>Ethoxylation product of N-ethyl-diethanolamine, OH number 470</dd><dt>D₅:</dt><dd>Ethoxylation product of glycerin, OH number 250</dd></dl> Long chain polyol:<dl id="dl0005"><dt>D₆:</dt><dd>Polyether polyol, OH number 42, based on 84% trimethylolpropane and 16% propylene glycol, first 5% propoxylated, then mixed propoxylated with 30% ethylene oxide, 40% propylene oxide, then end-propoxylated with 25% propylene oxide.</dd></dl> Additive:<dl id="dl0006"><dt>P₁:</dt><dd>Commercial polyether polysiloxane stabilizer from Goldschmidt AG.</dd></dl>

0049The mixtures (M₁ to M₄) were produced from the release agent types S and E in 10% mixing steps, eg mixture series M₁ from S₁ and E₁:<tables id="tabl0002" num="0002"><img file="EP0579080A2_D0001.tif" /></tables><dl id="dl0007"><dt>M₂</dt><dd>is the mixture series of S₂ and E₁</dd><dt>M₃</dt><dd>is the mixture series of S₂ and E₂</dd><dt>M₄</dt><dd>is the mixture series of S₂ and -CONH group-free ester according to the invention from 2 mol oleic acid and 1 mol N-methyldiethanolamine.</dd></dl>

0050The following polyol mixtures (M11 to M16) were produced: <tables id="tabl0003" num="0003"><table frame="all"><tgroup cols="7" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="22.50mm" /><colspec colnum="2" colname="col2" colwidth="22.50mm" /><colspec colnum="3" colname="col3" colwidth="22.50mm" /><colspec colnum="4" colname="col4" colwidth="22.50mm" /><colspec colnum="5" colname="col5" colwidth="22.50mm" /><colspec colnum="6" colname="col6" colwidth="22.50mm" /><colspec colnum="7" colname="col7" colwidth="22.50mm" /><thead valign="top"><row><entry namest="col1" nameend="col1" align="left">mixture</entry><entry namest="col2" nameend="col2" align="left">M11</entry><entry namest="col3" nameend="col3" align="left">M12</entry><entry namest="col4" nameend="col4" align="left">M13</entry><entry namest="col5" nameend="col5" align="left">M14</entry><entry namest="col6" nameend="col6" align="left">M15</entry><entry namest="col7" nameend="col7" align="left">M16</entry></row></thead><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">Tle D₁%</entry><entry namest="col2" nameend="col2" align="center">19,93</entry><entry namest="col3" nameend="col3" align="center">19,93</entry><entry namest="col4" nameend="col4" /><entry namest="col5" nameend="col5" /><entry namest="col6" nameend="col6" /><entry namest="col7" nameend="col7" /></row><row><entry namest="col1" nameend="col1" align="left">Tle D₂</entry><entry namest="col2" nameend="col2" align="center">29,89</entry><entry namest="col3" nameend="col3" align="center">29,89</entry><entry namest="col4" nameend="col4" align="center">29,89</entry><entry namest="col5" nameend="col5" align="center">29,89</entry><entry namest="col6" nameend="col6" align="center">29,89</entry><entry namest="col7" nameend="col7" align="center">29,89</entry></row><row><entry namest="col1" nameend="col1" align="left">Tle D₃</entry><entry namest="col2" nameend="col2" /><entry namest="col3" nameend="col3" /><entry namest="col4" nameend="col4" align="center">19,93</entry><entry namest="col5" nameend="col5" align="center">19,93</entry><entry namest="col6" nameend="col6" align="center">19,93</entry><entry namest="col7" nameend="col7" align="center">19,93</entry></row><row><entry namest="col1" nameend="col1" align="left">Tle D₄</entry><entry namest="col2" nameend="col2" align="center">4,53</entry><entry namest="col3" nameend="col3" align="center">4,53</entry><entry namest="col4" nameend="col4" align="center">4,53</entry><entry namest="col5" nameend="col5" align="center">4,53</entry><entry namest="col6" nameend="col6" align="center">4,53</entry><entry namest="col7" nameend="col7" align="center">4,53</entry></row><row><entry namest="col1" nameend="col1" align="left">Tle D₅</entry><entry namest="col2" nameend="col2" /><entry namest="col3" nameend="col3" align="center">27,64</entry><entry namest="col4" nameend="col4" /><entry namest="col5" nameend="col5" /><entry namest="col6" nameend="col6" /><entry namest="col7" nameend="col7" /></row><row><entry namest="col1" nameend="col1" align="left">Tle D₆</entry><entry namest="col2" nameend="col2" align="center">27,64</entry><entry namest="col3" nameend="col3" /><entry namest="col4" nameend="col4" align="center">27,64</entry><entry namest="col5" nameend="col5" align="center">27,64</entry><entry namest="col6" nameend="col6" align="center">27,64</entry><entry namest="col7" nameend="col7" align="center">27,64</entry></row><row><entry namest="col1" nameend="col1" align="left">Tle water</entry><entry namest="col2" nameend="col2" align="center">0,40</entry><entry namest="col3" nameend="col3" align="center">0,40</entry><entry namest="col4" nameend="col4" align="center">0,40</entry><entry namest="col5" nameend="col5" align="center">0,40</entry><entry namest="col6" nameend="col6" align="center">0,40</entry><entry namest="col7" nameend="col7" align="center">0,40</entry></row><row rowsep="1"><entry namest="col1" nameend="col1" align="left">Tle P₁</entry><entry namest="col2" nameend="col2" align="center">1,81</entry><entry namest="col3" nameend="col3" align="center">1,81</entry><entry namest="col4" nameend="col4" align="center">1,81</entry><entry namest="col5" nameend="col5" align="center">1,81</entry><entry namest="col6" nameend="col6" align="center">1,81</entry><entry namest="col7" nameend="col7" align="center">1,81</entry></row></tbody></tgroup></table></tables>

0051The polyol mixtures (M11 to M16) were mixed with release agent mixtures (M₁ to M₄) of types A to L in 10% steps, for example M11 with M₁A:<tables id="tabl0004" num="0004"><img file="EP0579080A2_D0002.tif" /></tables>

0052As already described above, the mixtures thus obtained were assessed after 148 hours in accordance with the classification given. Classes 1 to 3 are stable and classes 4 to 6 are unstable.

0053The polyol mixtures M11 to M16 are evaluated in admixture with the release agent mixtures M1 to M4 with regard to their stability on the basis of the specified classifications.

0054The designation of the overall mixture to be assessed corresponds to the given codes. For example, the name of the mixture of 80% polyol mixture M11 and 20% release agent mixture M₁H is thus M11, M₁H; c.<tables id="tabl0005" num="0005"><img file="EP0579080A2_D0003.tif" /></tables>

0055Examples 1 to 33 show that in the case of the polyol mixtures used in the area according to the invention with the release agent mixtures used in the area according to the invention, stable total mixtures are obtained within the scope of the mixture areas specified according to the invention (“mixture type area according to the invention”), whereas when one of the mixture areas specified according to the invention is left ("type of mixture not area according to the invention"), overall unstable mixtures (classification 4 to 6) can be obtained.

0056Examples 34 to 37 show that, if release agent mixtures according to the invention are not used (for example those of the Mmittel release agent mixture series), incompatibilities or inadequate stability are observed.