MXPA98003616A - Preparation of polyurethanes termoplasti - Google Patents

Abstract

In a process for preparing thermoplastic polyurethanes by reacting (a) isocyanates with (b) compounds reactive towards isocyanates, and having a molecular weight of 500 to 10,000 grams per mole, in the presence or absence of (c) chain extenders which have a molecular weight of less than 500 grams per mole, (d) catalysts and / or (e) auxiliaries and customary additives, the component (b) used comprises at least one polyether polyol (b1) comprising polyoxypropylene units and polyoxyethylene and having a molecular weight of 500 to 10,000 grams per mole, an unsaturation of less than 0.07 milliequivalent per gram and a primary hydroxyl group content of 80 percent to 100 percent

Description

"PREPARATION OF THERMOPLASTIC POLYURETHANES" The present invention relates to a process for preparing thermoplastic polyurethanes by reacting (a) isocyanates with (b) compounds reactive towards isocyanates and having a molecular weight of 500 to 10,000 grams per mole, in the presence or absence of (c) agents chain extenders having a molecular weight of less than 500 grams per mole, (d) catalysts and / or (e) customary auxiliaries and additives, and also the thermoplastic polyurethanes that can be prepared by this process. Further, the invention relates to polyol components comprising at least one polyether alcohol comprising polyoxypropylene and polyoxyethylene units and having a molecular weight of 500 to 10,000 grams per mole, an unsaturation of less than 0.07 milliequivalent per gram and a primary hydroxyl group content of 80 percent to 100 percent plus polytetrahydrofuran. The thermoplastic polyurethanes, which are also referred to below as TPU, are partially crystalline materials and belong to the class of thermoplastic elastomers. They have a combination of advantageous material properties such as low abrasion, good chemical resistance and simultaneously high flexibility and high strength with the advantages of economical thermoplastic processing which can be carried out continuously or in batches by various known methods, for example, the process of belt or extrusion. A total view of TPUs, their properties and applications is provided, for example, in "Kunststoff-Handbuch", volume 7, Polyurethane, third edition, 1993, edited by G. Oertel, Carl Hanser Verlag, Munich. To prepare TPUs, polytetrahydrofurans (PTHF) having molecular weights of 500 to 2000 grams per mole are used, such as polyether polyols, which will also be referred to below as polyols. The use of polypropylene glycols having molecular weights of 1000 to 4000 grams per mole to which terminal ethylene oxide units have been added in order to obtain primary hydroxyl groups, are described for the preparation of the TPU's in, for example, the U.S. Patent Number 5 185 420 and Patent Number WO 93/24549. The polyether polyols described in these documents, by way of example, containing 70 percent or 75.6 percent of primary hydroxyl groups, have the disadvantage of unsatisfactory reactivity to the isocyanates so that an undesirably high catalyst concentration is required for the reaction in the process of a single operation. In addition, TPUs prepared using these polyols have considerable disadvantages in their mechanical properties compared to PTHF-based TPUs. An object of the present invention is to develop a process for preparing thermoplastic polyurethanes having an improved reactivity of the polyol component, wherein the TPUs prepared by the process must have an improved mechanical property profile as compared to the previously known TPUs based on the polypropylene glycols. We have found that this object is achieved in the preparation of thermoplastic polyurethanes, by reacting (a) isocyanates with (b) compounds reactive towards isocyanates and having a molecular weight of 500 to 10,000 grams per mole, in the presence or absence of (c) chain extender agents having a molecular weight of less than 500 grams per mole, (d) catalysts and / or (e) auxiliaries and customary additives, using a component (b) comprising at least one polyether polyol (bl) comprising polyoxypropylene and polyoxyethylene units and having a molecular weight of 500 to ,000 grams per mole, an unsaturation of less than 0.07 milliequivalent per gram and a primary hydroxyl group content of 80 percent to 100 percent. The novel polyols of the component (bl) have an unsaturation of less than 0.07 milliequivalent per gram, preferably from 0.001 to 0.05 milliequivalent per gram, particularly preferably from 0.001 to 0.04 milliequivalent per gram, in particular from 0.001 to 0.01 milliequivalent per gram. The unsaturation customarily provided in milliequivalents per gram of the polyether polyalcohol can be determined by generally known methods, for example by the known Kaufmann method by means of bromination of the double bonds and subsequent iodometric evaluation. The unit of milliequivalent per gram usually corresponds to the content of the double bond in millimoles per gram of the polyether polyol. The molecular weight of the polyols (bl) is from 500 to 10,000 grams per mole, preferably from 1000 to 5000 grams per mole, and particularly preferably from 1000 to 2750 grams per mole. The hydroxyl number of the polyols (bl) is usually 10 to 230 milligrams of KOH per gram. The polyols preferably have a hydroxyl number of 52 to 110 milligrams of KOH per gram, particularly preferably 60 to 100 milligrams of KOH per gram. The functionality of the polyols depends on the unsaturation of the polyols and the functionality of the initiator molecules. For the preparation of thermoplastic polyurethanes, the functionality is preferably from 1.9 to 3.0, particularly preferably from 1.95 to 2.8, in particular from 1.95 to 2.2, since a higher functionality leads to crosslinked polyurethanes which make thermoplastic processing difficult. The polyols (bl) of the present invention can be prepared, for example, according to generally known methods by alkoxylation of the initiator substances which preferably has a functionality of 2 with alkylene oxides in the presence of, for example, basic salts of cesium, e.g., cesium hydroxide, and / or basic salts and / or alkaline earth metal hydroxides as catalysts. The catalysts used throughout the alkoxylation are preferably cesium hydroxide and / or calcium hydroxide. As initiator substances, preference is given to using the difunctional substances such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butane diols, for example, 1,4-butanediol, polyoxyethylene glycols and / or preferably polyoxypropylene glycols having customary molecular weights of less than 500 grams per mole. The higher functional initiator substances such as glycerol and / or trimethylpropane can be used as initiating substances, with the functionality of the novel polyols (bl) preferably prepared, being within the indicated scale. The polyols (bl) of the present invention comprise both polyoxyethylene and polyoxypropylene units. A preferred embodiment can be carried out, for example, by the sufficient addition of propylene oxide to the initiator substances in order to synthesize a block of polyoxypropylene units having a molecular weight of preferably at least 700 grams per mole, particularly preferably at least 900 grams per mole. This preferred block of polyoxypropylene units can either be added directly to the initiating substances or alternatively to the alkylene oxides which have already been added to the initiating substances. For example, the initiator substances can first be alkoxylated with additional alkylene oxides, for example, butylene oxide and / or preferably ethylene oxide, and subsequently as described with propylene oxide, or else first with propylene oxide and subsequently with additional alkylene oxides, for example, butylene oxide and / or preferably ethylene oxides. However, the polyoxypropylene block is preferably added directly to the initiating substances. In addition, the initiator can be alkoxylated with additional alkylene oxides, for example butylene oxide and / or preferably ethylene oxide, together with propylene oxide. Preference is given to the use of polyols containing from 5 percent to 30 percent by weight, particularly preferably from 15 percent to 25 percent by weight, in particular from 15 percent to 22 percent by weight of groups of polyoxyethylene, based on the total weight of all the polyoxyalkylene groups. Preferably, the polyols are finally alkoxylated with ethylene oxide, as a result of which the polyols (bl) have terminal polyoxyethylene groups. Specific preference is given to the block polymers wherein the first propylene oxide and then in the second step the ethylene oxide is added to the initiator substance. The proportion of the terminal polyoxyethylene units in the polyols (bl) of the present invention is preferably from 5 percent to 30 percent by weight, particularly preferably from 5 percent to 25 percent by weight, based on the total weight of all polyoxyalkylene groups. The ratio of the primary hydroxyl groups in the polyols (bl) is in accordance with the present invention, from 80 percent to 100 percent, preferably from 82 percent to 95 percent. The preparation of the polyols (bl) of the present invention, for example, can be carried out in the following manner: The initiating substances and the catalysts can preferably, after removing any water present at elevated temperature and reduced pressure, react with the propylene oxide and possibly with additional alkylene oxides in a customary reactor or autoclave, for example a stirred reactor or a tube reactor equipped with the usual facilities for cooling the reaction mixture. The catalyst is usually present in the reaction mixture in an amount of 0 to 10 parts per million, based on the total formulation. The alkoxylation is preferably carried out at the temperature of the reaction mixture within the range of 70 ° C to 150 ° C, particularly preferably 80 ° C to 105 ° C. The reaction is carried out at generally known pressures. The alkylene oxides as a general rule, can be added to the reaction mixture over a period of 4 to 20 hours, depending on the desired molecular weight of the polyol. Preferably, the propylene oxide is added at the beginning of the reaction so that, as described, a block of the polyoxypropylene units having a molecular weight of at least 700 grams per mole is added to the initiating substances . The reaction time can be from 1 to 8 hours, with the complete reaction of the alkylene oxides preferably being ensured. After completing the conversion, for example, of propylene oxide and possibly additional alkylene oxides, the polyoxyethylene units subsequently and especially preferably are added to the polyol end by the addition of ethylene oxide. Subsequently, the reaction mixture, as a rule, is cooled, preferably under reduced pressure, and worked in a known manner. For example, the cesium catalyst can be removed from the polyol by absorption or for example silicates and subsequent filtration. Alternatively, basic catalyst salts, for example, the aforementioned hydroxides, can be neutralized, e.g., by an appropriate acid such as phosphoric acid, and left in the polyol. Known stabilizers, e.g., against oxidation, can be subsequently added to the polyols. In addition to the polyol component (bl) of the present invention, it is possible to use, if desired, additional compounds reactive towards the isocyanates, for example, polyether polyols and / or polyester polyols, - lo ¬ which has a customary unsaturation of more than 0.07 milliequivalent per gram, and / or, for example, PTHF. The weight ratio of the polyols of the present invention based on the total weight of all the isocyanate-reactive compounds used in the preparation of the TPU, ie, the sum of the components (b) and (c), preferably at least 0.1 percent by weight, preferably from 0.1 percent to 90 percent by weight, particularly preferably from 30 percent to 90 percent by weight, in particular, from 40 percent to 80 percent by weight . Preference is given to the use of a polyol component (b) comprising both PTHF and polyols (bl) of the present invention. Specific preference is given to a polyol component comprising from 30 percent to 90 percent by weight, in particular from 40 percent to 80 percent by weight, of polyether polyol having a molecular weight of 500 to 1000 grams per mol, an unsaturation of less than 0.07 milliequivalent per gram, and from 80 percent to 100 percent of primary hydroxyl groups more than 10 percent to 70 percent by weight, in particular, from 20 percent to 60 percent in weight, of polytetrahydrofuran. The components (a), (b) and, if desired, (c), (d) and / or (e) which are used customarily in the preparation of the TPUs are described below by way of example: ( a) the appropriate organic isocyanates (a) are preferably aliphatic, cycloaliphatic and in particular aromatic diisocyanates. Specific examples are: aliphatic diisocyanates such as 1,6-hexamethylene diisocyanate, 1,5-methylpentamethylene diisocyanate, 1,4-diisocyanate of 2-ethylbutylene, or mixtures of at least 2, of alkylene diisocyanates of 6 carbon atoms mentioned, 1, 5-pentamethylene diisocyanate and 1,4-butylene diisocyanate, cycloaliphatic diisocyanates such as l-isocyanato-3, 3, 5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate), 1, 4-cyclohexane diisocyanate, 2,4- and 2,6-diisocyanate of 1-methylcyclohexane and also the corresponding isomer mixtures, 4,4'-, 2,4'- and 2, 2'-dicyclohexylmethane diisocyanate and also the corresponding isomer mixtures and preferably aromatic diisocyanates such as 2,4-toluene diisocyanate, mixtures of 2,4- and 2,6-toluene diisocyanate, 4,4'-, 2,4'- and 2,2 'diphenylmethane diisocyanate (MDl), mixtures of 2,4'- and 4,4'-diphenylmethane diisocyanate, 4,4'- and / or 2,4'-diisocyanates of liquid diphenylmethane modified with urethane, 4,4 '-diisocyanate (1,2-diphenylethane) and 1,5-naphthylene diisocyanate. Preference is given to the use of 1,6-hexamethylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate, isomer mixtures of diphenylmethane diisocyanate having a content of 4,4 '' diphenylmethane diisocyanate greater than 96. percent by weight and in particular 4, 4 '- diphenylmethane diisocyanate. b) In addition to the above-described polyols (bl) of the present invention, the isocyanate-reactive substances (b) that can be used are, for example, polyhydroxyl compounds having molecular weights of 500 to 10,000, preferably polyetherols and polyesterols. However, hydroxyl-containing polymers, for example polyacetals, such as polyoxymethylene and especially formally insoluble in water, eg, formal polybutanediol and polyhexanediol formal, and aliphatic polycarbonates, particularly those prepared from diphenyl carbonate and , 6-hexanediol by transesterification, having the aforementioned molecular weights, are also suitable. The mentioned polyhydroxyl compounds can be used as individual components or in the form of mixtures in addition to the polyols of the present invention. These polyols that can be used in addition to the polyols of the present invention are described below by way of example.

The mixtures for preparing the TPU or the TPU have to be based at least predominantly on substances that are difunctional in their reaction with the isocyanates. TPUs prepared using these mixtures therefore have a predominantly unbranched structure, that is, they are predominantly not cross-linked. Suitable polyetherols which, if desired, can be used in addition to the polyols (bl) can be prepared by known methods for example of one or more alkylene oxides having from 2 to 4 carbon atoms in the alkylene radical and, if is suitable, an initiator molecule containing 2 reactive hydrogen atoms in bound form by anionic polymerization, using alkali metal hydroxides such as sodium or potassium hydroxide, or alkali metal alkoxides such as sodium methoxide, sodium or potassium ethoxide or potassium isopropoxide as catalysts or by cationic polymerization using Lewis acids such as antimony pentachloride, boron fluoride etherate, etc., or bleaching earth as catalysts. Examples of the alkylene oxides are: ethylene oxide, 1,2-propylene oxide, tetrahydrofuran, 1,2- and 2,3-butylene oxide. Preference is given to the use of ethylene oxide and mixtures of 1,2-propylene oxide and ethylene oxide. The alkylene oxides can be used individually, alternatively in succession or as a mixture. Examples of suitable initiator molecules are: water, aminoalcohols, such as N-alkyldialkanolamines, for example, N-methyldiethanolamine and diols, such as alkanediols or dialkylene glycols having from 2 to 12 carbon atoms, preferably from 2 to 6 atoms of carbon, e.g., ethanediol, 1,3-propanediol, 1-butanediol and 1,6-hexanediol. If desired, it is also possible to use mixtures of the starter molecules. Other suitable polyetherols are the hydroxyl-containing polymerization products of tetrahydrofuran (polyoxytetramethylene glycols). If other polyetherols are used in addition to the polyether polyols (bl) of the present invention, preference is given to the use of polyetherols derived from 1,2-propylene oxide and ethylene oxide, wherein more than 50 percent, preferably from 60 percent to 80 percent of the OH groups are primary hydroxyl groups and wherein at least part of the ethylene oxide is placed as a terminal block and in particular polyoxytetramethylene glycols. These polyetherols can be obtained, for example, by first polymerizing the 1,2-propylene oxide to the initiator molecule and subsequently polymerizing in the ethylene oxide or by first copolymerizing all of the 1,2-propylene oxide mixed with part of the ethylene oxide. and subsequently polymerizing the remainder of the ethylene oxide or stepwise, first polymerizing part of the ethylene oxide to the initiator molecule and then polymerizing all of the 1,2-propylene oxide and then polymerizing the remainder of the ethylene oxide. The polyetherols, which are essentially linear in the case of TPUs, have customary molecular weights of 500 to 10,000, preferably 600 to 6000 and in particular, 800 to 3500. They can be used in addition to the polyols of the present invention and either individually or in the form of mixtures with one another. Suitable polyesterols which, if desired, can be used in addition to the polyols (bl), can be prepared, for example, from dicarboxylic acids having from 2 to 12 carbon atoms, preferably from 4 to 8 carbon atoms, and alcohols polyhydric Examples of suitable dicarboxylic acids are: aliphatic dicarboxylic acids such as succinic acid, glutaric acid, suberic acid, azelaic acid, sebacic acid and preferably adipic acid and aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid. The dicarboxylic acids can be used individually as mixtures, e.g., in the form of a mixture of succinic, glutaric and adipic acid. Similarly, mixtures of the aromatic and aliphatic dicarboxylic acids can be used. To prepare the polyesterols, it may be advantageous to replace the dicarboxylic acids with the corresponding dicarboxylic acid derivatives such as dicarboxylic esters having from 1 to 4 carbon atoms in the alcohol radical, dicarboxylic anhydrides or dicarboxylic acid chlorides. Examples of polyhydric alcohols are alkanediols having from 2 to 10, preferably from 2 to 6 carbon atoms, v.gr, ethanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1.6 -hexanediol, 1, 10, decanediol, 2,2-dimethylpropan-1, 3-diol, 1,2-propanediol and dialkylene ether glycols such as diethylene glycol and dipropylene glycol. Depending on the desired properties, the polyhydric alcohols can be used alone or in mixtures with one another. Carbonic acid esters with the diols mentioned are also suitable, in particular those having 4 to 6 carbon atoms, eg, 1,4-butanediol and / or 1,6-hexanediol, the condensation products of omega-hydroxycarboxylic acids, for example, omega-hydroxycaproic acid, and preferably the polymerization products of lactones, for example, substituted or unsubstituted omega-caprolactones. As polyesterols, preference is given to using alkanediol polyadipates having from 2 to 6 carbon atoms in the alkylene radical, v.gr, ethanediol polyadipates, 1,4-butanediol polyadipates, ethanediol-1,4 polyadipates. -butanediol, 1,6-hexanediol-neopentyl glycol polyadipates, polycaprolactones and in particular polyadipates of 1,6-hexanediol-1,4-butanediol. Polyesterols preferably have molecular weights of 500 to 6000, preferably 800 to 3500. c) Suitable chain extenders (c), which usually have molecular weights of less than 500 grams per mole, preferably from 60 to 300 grams per mole, preferably are the alkanediols having from 2 to 12 carbon atoms, preferably from 2, 4 or 6 carbon atoms, for example, ethanediol, 1,6-hexanediol and in particular 1, -butanediol and the dialkylene ether glycols such as diethylene glycol and dipropylene glycol. However, other suitable chain extenders are the diesters of terephthalic acid with alkanediols having from 2 to 4 carbon atoms, for example bis (ethanediol) or bis (1,4-butanediol) terephthalate, hydroxyalkylene ethers of hydroquinone, e.g., 1,4-di (beta-hydroxyethyl) hydroquinone, (cyclo) aliphatic diamines such as 4,4'-diaminodicyclohexylmethane, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane, l-amino- 3, 3, 5-trimethyl-5-aminomethylcyclohexane, ethylenediamine, 1 / 2- and 1,3-propylenediamine, N-methylpropylene-1,3-diamine, N, N'-dimethylethylenediamine and the aromatic diamines, such as 2, 4- and 2,6-diamine of toluene, 3,5-diethyltolylene-2,4,6,6-diamine and 4,4'-diaminodiphenylmethanes, ortho-dialkyl, trialkyl and / or tetraalkyl-substituted. The chain extenders which are preferably used are the alkanediols having from 2 to 6 carbon atoms in the alkylene radical, in particular 1,4-butanediol, and / or dialkylene glycols having from 4 to 8 carbon atoms. To adjust the hardness and melting temperature of the TPU, the molar ratios of the forming components (b) and (c) can be varied within relatively broad ranges. The molar ratios of the polyhydroxyl compounds (b) with respect to the chain extenders (c) which have been found to be useful are from 1: 1 to 1: 12, in particular from 1: 1.8 to 1: 6.4, with the hardness and melting temperature of the TPU increasing with the increased diol content. d) Suitable catalysts which, in particular, accelerate the reaction between the NCO groups of the diisocyanates (a) and the hydroxyl groups of the forming components (b) and (c), are the customary catalysts known in the prior art, for example, tertiary amines such as triethylamine, dimethylcyclohexylamine, N-methylmorpholino, N, N'-dimethylpiperazine, 2- (dimethylaminoethoxy) ethanol, diazabicyclo [2.2.2] octane and the like and also, in particular, organic metal compounds such as titanate esters, iron compounds such as iron (III) acetylacetonate, tin compounds such as tin diacetate, tin dioctoate, tin dilaurate, or dialkyltin salts of aliphatic carboxylic acids, e.g., dibutyltin diacetate, dibutyltin dilaurate or the like. The catalysts are usually used in amounts of 0.002 to 0.1 part per 100 parts of the polyhydroxyl compound (b). e) In addition to the catalysts, customary auxiliaries and / or additives (e) can be added to the forming components (a) to (c). Examples which may be mentioned are surface-active substances, foam stabilizers, cell regulators, flame-retardant agents, nucleating agents, oxidation inhibitors, stabilizers, lubricants and mold release agents, dyes and pigments, inhibitors, stabilizers against hydrolysis, light, heat or discoloration, inorganic and / or organic fillers or fillers, reinforcing materials and plasticizers. Additional details related to the aforementioned auxiliaries and additives can be found in the specialized literature, for example the monograph by J.H., Saunders and K.C. Frisch "High Polymers", volume XVI, Polyurethane, parts 1 and 2, Interscience Publishers 1962 and 1964, Kunststoff-Handbuch, volume XII, Polyurethane or DE-A 29 01 774. Thermoplastic elastomers can be prepared by known methods, example, in a single operation process, continuously in belt units or using reaction extrusion apparatus and also intermittently in the molding process as well as by a known pre-polymer process. In these processes, components (a), (b) and, if desired, (c) reacting can be mixed successively or simultaneously with one another, beginning the reaction immediately. The preferred reaction is carried out by a one-step process. Reagents (a), (b) and, if desired, (c) are preferably used in a ratio such that the ratio of the NCO groups of the component is (a) to the sum of all the atoms in the NCO-reactive hydrogens of the components (b) and, if used (c) is from 1: 0.9 to 1: 1.1.2, particularly preferably from 1: 0.95 to 1: 1.1, in particular of 1: 1. The reaction is exothermic and usually progresses rapidly.

As already mentioned, the reaction mixture comprising (a), (b) and, if desired, (c), (d) and / or (e) can be reacted by the extrusion process or preferably through the belt process. In a special way, in the belt process, the procedure is as follows: The forming components (a) to (c) and, if desired, (d) and / or (e) are mixed continuously at temperatures above the melting temperature of the forming components (a) to (c) by means of a mixing head. The reaction mixture is applied to a support, preferably a conveyor belt and transported through the heated zone. The reaction temperature in the heated zone can be from 60 ° to 200 ° C, preferably from 100 ° C to 180 ° C, and the residence time is usually from 0.05 to 0.5 hour, preferably from 0.1 to 0.3. hour. After the reaction is complete, the TPU is allowed to cool and is subsequently ground or granulated. In the extrusion process, the forming components (a) to (c) and, if desired, (d) and (e) are introduced individually or as a mixture in the extrusion apparatus, being reacted at for example a temperature of 100 ° C to 250 ° C, preferably 140 ° C to 220 ° C, and the resulting TPU is extruded, cooled and granulated.

The processing of TPUs, which are usually in the form of granules or powders, is carried out by customary methods. For example, TPUs are mixed, for example, at a temperature of 0 ° C. at 200 ° C, preferably from 60 ° C to 150 ° C and in particular from 80 ° C to 120 ° C. The mixture can subsequently be homogenized at a temperature of 150 ° C to 250 ° C, preferably 160 ° C to 230 ° C and in particular 180 ° C to 220 ° C, for example, in a flowing, smoothed or melted state, preferably with degassing, e.g., by stirring, rolling, kneading or extruding, for example using a roller apparatus, a kneader or an extrusion apparatus, and forming the desired TPUs continues. Preferably, the TPUs are introduced as mixtures or individually in an extrusion apparatus, partially melted, for example, at a temperature of 150 ° C to 250 ° C, preferably 160 ° C to 230 ° C and in particular 180 ° C. C at 220 ° C, the mixture is extruded, e.g., in an individual or twin screw machine, for example with degassing, cooled and subsequently granulated. The granules can be subjected to intermediate storage or can be further processed immediately to provide the desired products. The advantages in accordance with the present invention are illustrated by the following examples.

Example 1 Thermoplastic polyurethanes of 700 parts of MDl, 175 parts of butanediol were prepared as the chain extender (rigid segment content = 39 percent) and 1000 parts of a polyether polyol or le based on the polyoxypropylene units and units of polyoxyethylene and having the characteristics shown in Table 1, through the process of a single known operation.

Table 1 Polyester polyol li le Molecular Weight 1250 2000 Hydroxyl number [mg KOH / gram] 90 50 Unsaturation [milliequivalents / gram] 0.008 0.01 Proportion of primary hydroxyl groups [%] 85 75 Weight proportion of polyoxyethylene units [%] 20 27 Functionality 1.99 1.9I TPUs prepared using polyether polyols have the properties shown in Table 2.

Table 2 Sample TPU Shore Density Abrasion Polialcohol of Hardness g / cm- mm-Polyether A li 90 1.16 58 le 89 1.13 108 Table 2 (continued) TPU Sample Resistance Resistance Lengthens Propagation Tension to Break Break Polyalcohol of N / mm2 N / mm Polyether li 57 63 610 37 530 TPUs prepared using the polyether polyol component li according to the present invention have significantly improved properties compared to TPUs based on the known polyether polyols. The tensile strength, the resistance to breakage propagation and the elongation at break of the TPUs prepared according to the present invention, increase significantly while the abrasion was able to be reduced.

Example 2 Samples of thermoplastic polyurethane incorporating polymer diols of 600 parts of MDI, 140 parts of butanediol (rigid segment content = 30 percent) and 1000 parts of the polymer diol were prepared by the single-operation process, wherein the Diol component is a mixture of the polyether polyol li and a polytetrahydrofuran diol (PTHF) having a molecular weight of 1000: Ratio in Weight Shore Density Abrasion polyol of polyether li: PTHF Hardness A g / cm- mm- 100: 0 84 1.15 86 90:10 83 1.15 90 80:20 84 1,145 97 70:30 84 1.14 81 60:40 84 1.14 78 50:50 84 1,135 61 40:60 85 1.13 54 :70 85 1.13 52 (Continuation) Relationship in Weight Resistance Resistance-polyol of Propagation polyether li: PTHF tension at break to break N / mm2 N / mm 100: 0 38 45 610 90:10 42 50 710 80:20 41 48 720 70:30 41 48 740 60:40 46 46 720 50:50 44 50 710 40:60 53 51 670 :70 56 52 650 - 21 It will be seen that the thermoplastic polyurethanes that have been prepared using the blends of the present invention have excellent properties.

Example 3 The mechanical properties of the thermoplastic polyurethane samples incorporating polymer diols, prepared from 600 parts of MDl, 140 parts of butanediol (rigid segment content = 30 percent) and 1000 parts of polymer diol, where the diol component used was polyether polyol li. according to the present invention or polyether polyol, for comparison were examined. The materials were prepared by the process of a single conventional operation with the temperature recorded as a function of time during the reaction (Table 4) Table 4 Times] 10 20 30 40 50 60 70 80 90 100 110 li [° C] 74 81 87 94 100 106 113 119 le [° C] 75 81 86 92 97 102 105 110 114 117 120 The slow temperature rise in the reaction of the comparison polyether polyol clearly shows that the reaction with the component is unsatisfactorily slow. In contrast, the rate at which the reaction temperature increases in the reaction with the li component of the present invention, shows a desirably rapid reaction from which it can be concluded that the conversion is still complete in the preparation of the TPU through the process of a single operation. The mechanical properties of TPUs are shown in Table 5: Table 5 Sample TPU Shore Density Abrasion a single hardness g / cm ^ mm ^ operation A 3i 85 1.15 83 3c 85 1.14 192 Table 5 (continued) TPU Sample Strength Resistance Lengthens the tension to the Propagation to the Breakage Break One single N / mm2 N / mm operation 3i 39 45 620 3c 20 36 810 In addition, the TPUs that were prepared using the polyether polyol li in accordance with the present invention have considerably improved mechanical properties. Thus, for example, abrasion, tensile strength and resistance to break propagation are significantly improved compared to TPU 3c which was prepared using the polyether polyol.