Method for producing transparent rigid thermoplastic polyurethane

Abstract

To provide a thermoplastic polyurethane which is firstly transparent and has high hardness and a high elastic modulus and secondly has very good elongation at break and to provide a method for producing the same.SOLUTION: There is provided a transparent thermoplastic polyurethane which can be obtained or was obtained by converting (i) a polyisocyanate composition, (ii) at least one chain extender and (iii) at least one polyol composition, wherein the polyol composition includes at least one polyol (P1) having molecular weight Mw in the range of 500 to 2000 g / mol and at least one aromatic polyester block (B1) and a hard segment content is<75%, the chain extender used in (ii) is a diol having molecular weight of Mw<220 g / mol and the chain extender used in (ii) and the polyol (P1) present in the polyol composition are used in a molar ratio of 40:1 to 1:10.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a thermoplastic polyurethane obtained or obtained by converting a polyisocyanate composition, a chain extender, and a polyol composition, wherein the polyol composition comprises a polyol (P1) having a molecular weight Mw in the range of 500 to 2000 g / mol and at least one aromatic polyester block (B1), and the hard segment content of the thermoplastic polyurethane is less than 75%. The present invention further relates to a method for producing a molded article comprising such a thermoplastic polyurethane, and a molded article obtained or obtained by the method of the present invention. [Background technology]

[0002] Thermoplastic polyurethanes for various applications are generally known from the prior art. By varying the feedstock, different aspects of the properties can be obtained.

[0003] US5574092 discloses rigid thermoplastic polyurethanes having a Tg of at least 50°C, which contain hard segments based on diisocyanates and chain extender mixtures containing aromatic diols. According to the examples, very brittle materials are obtained with elongations at break of less than 170%.

[0004] US5627254 describes the unit of butanediol (BDO) and HO-(CH2CH2O) n Rigid thermoplastic polyurethanes containing polyethylene glycol (PEG) units of the -H type (n is an integer from 2 to 6) have been disclosed. These materials have the disadvantage of being brittle and difficult to process.

[0005] WO 2015 / 063062 A1 relates to thermoplastic polyurethanes obtainable or obtained by reacting at least one aliphatic polyisocyanate, at least one chain extender, and at least one polyol composition. The polyol composition comprises a polyol selected from the group consisting of polyetherols and at least one bisphenol derivative selected from the group consisting of bisphenol A derivatives having a molecular weight Mw>315 g / mol and bisphenol S derivatives having a molecular weight Mw>315 g / mol, wherein at least one of the OH groups of the bisphenol derivative is alkoxylated. The document also describes a method for producing the thermoplastic polyurethanes and a method for using the thermoplastic polyurethanes of the invention for the production of extruded products, films, and molded articles. Such aliphatic TPUs have a hardness >70 Shore D, but a low modulus and a completely insufficient elongation at break. A further disadvantage is the use of bisphenol A, which is of some concern from a toxicological point of view.

[0006] Typically, rigid thermoplastic polyurethanes have a hard segment content of 75% or more and are obtained by reacting isocyanates with chain extenders, such as hexane-1,6-diol or cyclohexane-1,4-dimethanol. These materials have high hardness and high dimensional stability, but are very brittle, with elongations at break of less than 200% or even less than 100%.

[0007] However, many applications require materials that not only have high hardness, i.e. in particular a hardness >75 Shore D and a modulus >2000 MPa at room temperature, but also a good elongation at break of more than 300%. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] US5574092 [Patent Document 2] US5627254 [Patent Document 3] WO2015 / 063062A1 Summary of the Invention [Problem to be solved by the invention]

[0009] In progress from the prior art, it was an object of the present invention to provide a thermoplastic polyurethane which is firstly transparent, has a high hardness and a high modulus, and secondly has a very good elongation at break. A further object of the present invention was to provide a thermoplastic polyurethane which is firstly transparent, has a high hardness and a high modulus, and secondly has a very good elongation at break, and which can be produced in a simple and inexpensive manner, in a one-shot process. [Means for solving the problem]

[0010] This object is achieved according to the present invention by providing a composition comprising at least components (i) to (iii): (i) a polyisocyanate composition; (ii) at least one chain extender, and (iii) at least one polyol composition 1. A thermoplastic polyurethane obtained or obtained by converting The polyol composition comprises at least one polyol (P1) having a molecular weight Mw in the range of 500 to 2000 g / mol and having at least one aromatic polyester block (B1), The hard segment content in the thermoplastic polyurethane is <75%; This can be achieved with thermoplastic polyurethanes. DETAILED DESCRIPTION OF THE INVENTION

[0011] According to the present invention, the polyol (P1) has a molecular weight Mw in the range of 500 to 2000 g / mol. The polyol (P1) also has an aromatic polyester block (B1). This is understood to mean that the aromatic polyester block (B1) in the context of the present invention can be a polyester of an aromatic dicarboxylic acid and an aliphatic diol or a polymer of an aliphatic dicarboxylic acid and an aromatic diol. The aromatic polyester block (B1) in the context of the present invention is preferably a polyester of an aromatic dicarboxylic acid and an aliphatic diol. Suitable aromatic dicarboxylic acids here are, for example, terephthalic acid, isophthalic acid, or phthalic acid, with terephthalic acid being preferred. Thus, suitable polyols (P1) in the context of the present invention are, for example, those having at least one polyethylene terephthalate block or at least one polybutylene terephthalate block, in which the number of repeating units in the aromatic system is at least two in series. The aromatic polyester block (B1) is preferably prepared in a separate step prior to further conversion to a polyol to ensure sufficient block length of the repeating units in the aromatic system.

[0012] According to the invention, the thermoplastic polyurethane may in particular be a compact thermoplastic polyurethane. Thus, in a further embodiment, the invention relates to a thermoplastic polyurethane as described above, in which the thermoplastic polyurethane is a compact thermoplastic polyurethane.

[0013] Thus, in a further embodiment, the present invention relates to a thermoplastic polyurethane as described above, wherein the aromatic polyester block (B1) is a polyester of an aromatic dicarboxylic acid and an aliphatic diol. In a still further embodiment, the present invention relates to a thermoplastic polyurethane as described above, wherein the aromatic polyester block (B1) is a polyethylene terephthalate block or a polybutylene terephthalate block. In a still further embodiment, the present invention relates to a thermoplastic polyurethane as described above, wherein the aromatic polyester block (B1) is a polyethylene terephthalate block.

[0014] According to the present invention, the thermoplastic polyurethane has a hard segment content of <75%. The hard segment content here is the proportion of the thermoplastic polyurethane formed by the isocyanate and the chain extender. In the context of the present invention, the hard segment content is determined by the formula disclosed in WO 2007 / 118827 A1, where a value of 1.0 corresponds to 100%, and a hard segment content of <75% corresponds to a value of <0.75 according to the formula specified in WO 2007 / 118827 A1.

[0015] Surprisingly, the use of polyols (P1) with molecular weights Mw in the range of 500 to 2000 g / mol and at least one aromatic polyester block (B1) allows the production of transparent, hard, and non-brittle thermoplastic polyurethanes with a hard segment content of <75%. Thus, the thermoplastic polyurethanes of the present invention have a hardness of >75 Shore D, a modulus of elasticity at room temperature of >2000 MPa, and an elongation at break of >300%.

[0016] In the context of the present invention, suitable polyols (P1) are particularly those based on aromatic polyesters, such as polybutylene terephthalate (PBT) or polyethylene terephthalate (PET). The polyols (P1) are preferably prepared by reacting aromatic polyesters with dicarboxylic acids and diols to obtain mixed aromatic / aliphatic polyester diols. For example, in the context of the present invention, aromatic polyesters in solid or liquid form can be reacted with dicarboxylic acids and diols. According to the present invention, the aromatic polyesters used typically have a molecular weight greater than that of the blocks (B1) present in the polyol (P1).

[0017] The polyester polyols (P1) suitable according to the invention typically comprise 20% to 70% by weight, preferably 30% to 60% by weight, more preferably 35% to 55% by weight, and even more preferably 40% to 50% by weight of aromatic polyester blocks (B1) (in each case based on the total polyester polyol (P1)). In a further embodiment, the invention therefore relates to a thermoplastic polyurethane as described above, in which the polyol (P1) comprises 20% to 70% by weight of aromatic polyester blocks (B1), based on the total polyester polyol (P1).

[0018] According to the invention, the polyol (P1) has a molecular weight Mw in the range from 500 to 2000 g / mol, preferably in the range from 750 to 1500 g / mol, more preferably in the range from 900 to 1200 g / mol, most preferably in the range from 950 to 1050 g / mol. In a further embodiment, the invention therefore relates to a thermoplastic polyurethane as described above, in which the polyol (P1) has a molecular weight Mw in the range from 750 to 1500 g / mol.

[0019] The molecular weight (Mw) is calculated using the following formula (where z is the functionality of the polyester polyol and z=2): Mw=1000mg / g[(z·56.106g / mol) / (OHN[mg / g])]

[0020] In the preparation of polyol (P1), it is preferable to use aromatic polyesters such as polybutylene terephthalate (PBT) or polyethylene terephthalate (PET). Polyethylene terephthalate is a thermoplastic polymer that can be produced by polycondensation. The quality of PET and its physical properties, such as toughness or durability, depend on the chain length. The old PET synthesis method was based on the transesterification of dimethyl terephthalate with ethylene glycol. Today, PET is almost exclusively synthesized by the direct esterification of terephthalic acid with ethylene glycol. Similarly, polybutylene terephthalate (PBT) can be obtained by reacting terephthalic acid with butane-1,4-diol. Similar thermoplastic polymers are available under trade names such as CRASTIN® (DuPont), POCAN® (Lanxess), ULTRADUR® (BASF), or ENDURAN® and VESTODUR® (SABIC IP). The chemical and physical / technical properties of this thermoplastic polymer roughly correspond to those of PET.

[0021] According to the present invention, it is also possible to use aromatic polyesters such as polybutylene terephthalate (PBT) or polyethylene terephthalate (PET) obtained from recycling processes. For example, polyethylene terephthalate can be used in the form of flakes obtained from plastic recycling processes. This type of material typically has a molecular weight of about 12,000 g / mol.

[0022] According to the invention, suitable polyols (P1) can also be obtained by transesterification of aromatic polyesters, such as polybutylene terephthalate or polyethylene terephthalate, having higher molecular weights with diols. Suitable reaction conditions are known per se to those skilled in the art.

[0023] Furthermore, diols having 2 to 10 carbon atoms, such as ethanediol, propanediol, butanediol, pentanediol, hexanediol, or di- or triethylene glycol, especially butane-1,4-diol, or mixtures thereof, are used to prepare polyol (P1). Short polyether diols, such as PTHF250 or PTHF650, or short-chain polypropylene glycols, such as PPG500, can also be used. The dicarboxylic acids used can be, for example, linear or branched diacids having 4 to 12 carbon atoms or mixtures thereof. Adipic acid, succinic acid, glutaric acid, or sebacic acid, or mixtures of these acids, are preferably used. Adipic acid is particularly preferred in the context of the present invention. According to the present invention, it is also possible to use additional polyester diols, such as butanediol adipate or ethylene adipate, as raw materials for the preparation of polyol (P1).

[0024] In the context of the present invention, it is essential to use at least one chain extender and a polyol composition as described above in the preparation of the thermoplastic polyurethane.

[0025] According to the invention, it is possible to use one chain extender, but also a mixture of different chain extenders.

[0026] The chain extender used in the present invention can be, for example, a compound having a hydroxyl group or an amino group, in particular a compound having two hydroxyl groups or two amino groups.However, according to the present invention, it is also possible to use a mixture of different compounds as a chain extender.In that case, according to the present invention, the average functionality of the mixture is 2.

[0027] According to the present invention, it is preferable to use a compound having a hydroxyl group, particularly a diol, as a chain extender. It is preferable to use an aliphatic, araliphatic, aromatic, and / or alicyclic diol having a molecular weight of 50 g / mol to 220 g / mol. Alkanediols having 2 to 10 carbon atoms in the alkylene group are preferred, particularly di-, tri-, tetra-, penta-, hexa-, hepta-, octa-, nona-, and / or deca-alkylene glycols. In the present invention, 1,2-ethylene glycol, propane-1,3-diol, butane-1,4-diol, and hexane-1,6-diol are particularly preferred. It is also possible to use aromatic compounds such as hydroxyquinone (bis(2-hydroxyethyl)) ether.

[0028] According to the invention, it is also possible to use compounds containing amino groups, such as diamines, as well as mixtures of diols and diamines.

[0029] As chain extenders, diols with a molecular weight M<220 g / mol are preferred. According to the invention, it is possible to use only one diol with a molecular weight M<220 g / mol for the preparation of transparent thermoplastic polyurethanes.

[0030] In a further embodiment, two or more diols are used as chain extenders. It is therefore also possible to use a mixture of chain extenders, where at least one diol has a molecular weight M<220 g / mol. When two or more chain extenders are used, the second or subsequent chain extenders can have a molecular weight of ≧220 g / mol.

[0031] In a further embodiment, the chain extender is selected from the group consisting of butane-1,4-diol and hexane-1,6-diol.

[0032] In a further embodiment, the present invention therefore relates to a thermoplastic polyurethane as described above, wherein the chain extender used in (ii) is a diol with a molecular weight Mw<220 g / mol.

[0033] The chain extender, particularly a diol having a molecular weight Mw<220 g / mol, is preferably used in a molar ratio of 40:1 to 1:10 relative to the polyol (P1). The chain extender and polyol (P1) are preferably used in a molar ratio of 20:1 to 1:9, more preferably 10:1 to 1:8, for example 5:1 to 1:5, or 4:1 to 1:4, more preferably 3:1 to 1:2.

[0034] In a further embodiment, the present invention therefore relates to a thermoplastic polyurethane as defined above, wherein the chain extender used in (ii) and the polyol (P1) present in the polyol composition are used in a molar ratio of 40:1 to 1:10.

[0035] According to the present invention, the polyol composition can comprise a further polyol and said at least one polyol (P1).It is therefore also possible to use in the context of the present invention a polyol composition comprising at least one chain extender and said at least one polyol (P1) and at least one further polyol.

[0036] In another embodiment, the present invention provides a thermoplastic polyurethane as described above, wherein the polyol composition comprises an additional polyol selected from the group consisting of polyetherols, polyesterols, polycaprolactone alcohols, and hybrid polyols.

[0037] The high molecular weight compound having a hydrogen atom reactive with isocyanate used may be a commonly known polyol having a compound reactive with isocyanate.

[0038] Polyols are known in principle to those skilled in the art and are described, for example, in "Kunststoffhandbuch [Plastics Handbook], Volume 7, Polyurethanes", Carl Hanser Verlag, 3rd Edition, 1993, Chapter 3.1. It is particularly preferred to use polyesterols or polyetherols as polyols. Polyester polyols are particularly preferred. It is likewise possible to use polycarbonates. Copolymers can also be used in the context of the present invention. The number-average molecular weight of the polyols that can be used according to the present invention is preferably 0.5 x 10 3 g / mol~8×10 3 g / mol, preferably 0.6 × 10 3 g / mol ~ 5 × 10 3 g / mol, specifically 0.8 × 10 3 g / mol ~ 3 × 10 3 g / mol.

[0039] These materials preferably have an average functionality with respect to isocyanates of 1.8 to 2.3, more preferably 1.9 to 2.2, especially 2.

[0040] The polyesterol used may be a polyesterol based on a diacid and a diol. The diol used is preferably a diol having 2 to 10 carbon atoms, such as ethanediol, propanediol, butanediol, pentanediol, hexanediol, or di- or triethylene glycol, particularly butane-1,4-diol, or a mixture thereof. The diacid used may be any known diacid, such as a linear or branched diacid having 4 to 12 carbon atoms, or a mixture thereof. Adipic acid is preferably used as the diacid.

[0041] Suitable polyetherols according to the invention are polyethylene glycol, polypropylene glycol and polytetrahydrofuran.

[0042] In a particularly preferred embodiment, the polyol is polytetrahydrofuran (PTHF) having a molecular weight in the Mw range of 600 g / mol to 2500 g / mol.

[0043] As well as PTHF, various other polyethers are suitable according to the invention, but polyesters, block copolymers and hybrid polyols such as poly(ester / amides) can also be used.

[0044] The polyols used preferably have an average functionality of 1.8 to 2.3, preferably 1.9 to 2.2, in particular 2. The polyols used according to the invention preferably have only primary hydroxyl groups.

[0045] According to the invention, the polyol can be used in pure form or in the form of a composition comprising said polyol and at least one solvent, suitable solvents being known per se to those skilled in the art.

[0046] The additional polyol is preferably used in a molar ratio to the polyol (P1) ranging from 10:1 to 1:10. In a further preferred embodiment, the further polyol and the polyol (P1) are used in a molar ratio ranging from 9:1 to 1:9, more preferably from 5:1 to 1:5.

[0047] According to the invention, at least one polyisocyanate is used. According to the invention, it is also possible to use a mixture of two or more polyisocyanates.

[0048] Suitable polyisocyanates in the context of the present invention are diisocyanates, especially aliphatic or aromatic diisocyanates, more preferably aromatic diisocyanates.

[0049] In a further embodiment, the present invention therefore relates to a thermoplastic polyurethane as described above, wherein the polyisocyanate is an aliphatic or aromatic diisocyanate.

[0050] According to the present invention, the components are converted at a ratio such that the hard segment content in the thermoplastic polyurethane is <75%, preferably <70%, more preferably <50%, and even more preferably <40%. Therefore, the hard segment content in the thermoplastic polyurethane is preferably in the range of 10% to 75%, preferably in the range of 20% to 70%, more preferably in the range of 20% to 50%, and even more preferably in the range of 20% to 40%.

[0051] Furthermore, in the context of the present invention, the isocyanate components used may be pre-reacted prepolymers in which some of the OH moieties have reacted with isocyanates in a previous reaction step. These prepolymers react with the remaining OH moieties in a further step, the actual polymer reaction, to then form the thermoplastic polyurethane. The use of prepolymers makes it possible to use OH moieties with secondary alcohol groups.

[0052] Aliphatic diisocyanates that can be used include conventional aliphatic and / or cycloaliphatic diisocyanates, such as tri-, tetra-, penta-, hexa-, hepta- and / or octamethylene diisocyanate, 2-methylpentamethylene 1,5-diisocyanate, 2-ethyltetramethylene-1,4-diisocyanate, hexamethylene-1,6-diisocyanate (HDI), pentamethylene-1,5-diisocyanate, butylene-1,4-diisocyanate, trimethylhexamethylene-1,6-diisocyanate, hexam ... ,6-diisocyanate, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate, IPDI), 1,4- and / or 1,3-bis(isocyanatomethyl)cyclohexane (HXDI), cyclohexane-1,4-diisocyanate, 1-methylcyclohexane 2,4- and / or 2,6-diisocyanate, methylenedicyclohexyl 4,4'-, 2,4'- and / or 2,2'-diisocyanate (H12MDI), and the like.

[0053] Preferred aliphatic polyisocyanates are hexamethylene 1,6-diisocyanate (HDI), 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane and methylenedicyclohexyl 4,4'-, 2,4'- and / or 2,2'-diisocyanate (H12MDI). Particularly preferred are methylenedicyclohexyl 4,4'-, 2,4'- and / or 2,2'-diisocyanate (H12MDI) and 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane or mixtures thereof.

[0054] In a further embodiment, the present invention therefore relates to a process as described above, wherein the polyisocyanate is selected from the group consisting of methylenedicyclohexyl 4,4'-, 2,4'- and / or 2,2'-diisocyanate (H12MDI), hexamethylene diisocyanate (HDI) and 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (IPDI) or mixtures thereof. Suitable aromatic diisocyanates are, in particular, diphenylmethane 2,2′-, 2,4′- and / or 4,4′-diisocyanate (MDI), naphthylene 1,5-diisocyanate (NDI), tolylene 2,4- and / or 2,6-diisocyanate (TDI), 3,3′-dimethyl-4,4′-diisocyanatodiphenyl (TODI), p-phenylene diisocyanate (PDI), diphenylethane 4,4′-diisocyanate (EDI), diphenylmethane diisocyanate, dimethyldiphenyl 3,3′-diisocyanate, diphenylethane 1,2-diisocyanate and / or phenylene diisocyanate.

[0055] Suitable aromatic diisocyanates are diphenylmethane 2,2'-, 2,4'- and / or 4,4'-diisocyanate (MDI) and mixtures thereof.

[0056] Suitable examples of more highly functional isocyanates are triisocyanates, such as triphenylmethane 4,4',4''-triisocyanate, and also the cyanurates of the abovementioned diisocyanates, and oligomers obtained by partial reaction of diisocyanates with water, such as biurets of the abovementioned diisocyanates, and also oligomers obtained by controlled reaction of semi-blocked diisocyanates with polyols having an average of more than two, preferably three or more, hydroxyl groups.

[0057] In a further embodiment, the present invention relates to the above method, wherein the polyisocyanate is an aliphatic diisocyanate.

[0058] According to the present invention, the polyisocyanate can be used in pure form or in the form of a composition comprising the polyisocyanate and at least one solvent. Suitable solvents are known to those skilled in the art. Suitable examples include non-reactive solvents such as ethyl acetate, methyl ethyl ketone, tetrahydrofuran, and hydrocarbons.

[0059] According to the present invention, in the reaction of the at least one aliphatic polyisocyanate, the at least one chain extender, and the at least one polymer composition, it is possible to add further raw materials, such as catalysts or auxiliaries and additives.

[0060] Suitable auxiliaries and additives are known to those skilled in the art.Specific examples include, for example, surface-active substances, flame retardants, nucleating agents, oxidation stabilizers, antioxidants, lubricants and release aids, dyes and pigments, stabilizers (against hydrolysis, light, heat, or discoloration), inorganic and / or organic fillers, reinforcing agents, and plasticizers.Suitable auxiliaries and additives are described, for example, in Kunststoffhandbuch (Plastics Handbook), Vol. VII, published by Vieweg and Hoechtlen, Carl Hanser Verlag, Munich 1966 (pp. 103-113).

[0061] Suitable catalysts are likewise known in principle from the prior art. Suitable catalysts are, for example, organometallic compounds selected from the group consisting of organyls of tin, titanium, zirconium, hafnium, bismuth, zinc, aluminum and iron, such as tin organyl compounds, preferably tin dialkyls, such as tin(II) isooctate, tin dioctoate, dimethyltin, diethyltin, or tin organyl compounds of aliphatic carboxylic acids, preferably tin diacetate, tin dilaurate, dibutyltin diacetate, dibutyltin dilaurate, titanate esters, bismuth compounds, such as bismuth alkyl compounds, preferably bismuth neodecanoate or similar, or iron compounds, preferably iron(III) acetylacetonate.

[0062] In a preferred embodiment, the catalyst is selected from tin and bismuth compounds, more preferably tin or bismuth alkyl compounds, with tin(II) isooctanoate and bismuth neodecanoate being particularly suitable.

[0063] The catalyst is typically used in an amount of 3 ppm to 2000 ppm, preferably 10 ppm to 1000 ppm, more preferably 20 ppm to 500 ppm, and most preferably 30 ppm to 300 ppm.

[0064] In a further aspect, the present invention also provides a method for producing a medicament for the preparation of ... (a) (i) at least one polyisocyanate composition; (ii) at least one chain extender, and (iii) at least one polyol composition producing a thermoplastic polyurethane comprising the composition of where: The polyol composition comprises at least one polyol (P1) having a molecular weight Mw in the range of 500 to 2000 g / mol and having at least one aromatic polyester block (B1), The hard segment content in the thermoplastic polyurethane is <75%; and (b) A process for producing a molded body (SC) from thermoplastic polyurethane The present invention relates to a method for producing a molded body (SC) comprising:

[0065] The method according to the present invention comprises steps (a) and (b). First, in step (a), a thermoplastic polyurethane is prepared by reacting at least one polyisocyanate composition, at least one chain extender, and at least one polyol composition. According to the present invention, the polyol composition comprises at least one polyol (P1) having a molecular weight Mw in the range of 500 to 2000 g / mol and having at least one aromatic polyester block (B1).

[0066] In step (b), a molded body (SC) is produced from the thermoplastic polyurethane obtained in step (a). In the context of the present invention, the molded body (SC) can also be, for example, a foil. In the context of the present invention, the molded body (SC) can be produced by any conventional method, for example, by extrusion, injection molding, or sintering, or from a solution. In particular, the production of the molded body (SC) by injection molding is preferred in the context of the present invention.

[0067] In a further embodiment, the present invention therefore relates to a method as described above, wherein the shaped body (SC) is produced in step (b) by extrusion, injection molding or sintering processes or from a solution.

[0068] The process of step (a) can in principle be carried out under reaction conditions known per se.

[0069] In a preferred embodiment, the process of step (a) is carried out at a temperature above room temperature, more preferably in the range of 50°C to 200°C, more preferably in the range of 55°C to 150°C, especially in the range of 60°C to 120°C.

[0070] According to the present invention, heating can be performed by any suitable method known to those skilled in the art, preferably by electrical heating, heating via heated oil, heated polymer fluid or water, induction field, hot air or IR radiation.

[0071] The thermoplastic polyurethane obtained is processed according to the present invention to obtain a molded body (SC). The process accordingly comprises steps (a) and (b). According to the present invention, the method can include further steps, such as a heat treatment.

[0072] The process of the present invention allows for the production of shaped bodies (SC) which are transparent, have a high hardness and are not brittle at the same time. In a further aspect, the present invention also relates to shaped bodies obtainable or obtained by the process described above.

[0073] In principle, the molded body (SC) can be any conceivable shape, such as extrusion products such as films and other molded bodies.According to the present invention, the molded body can particularly include consumer articles, such as toothbrushes, razors, housings for household appliances, displays, computer or telephone parts, plugs, automobile interior parts, footwear parts, such as toe caps for safety shoes, etc.

[0074] In a further embodiment, the present invention therefore relates to a molding as described above, wherein the molding is a consumer article, for example a consumer article for use as a toothbrush, a razor, a housing for a household item, a display, a computer or telephone part, a plug, an automobile interior part, a footwear part, for example a toe cap for a safety shoe, etc.

[0075] Further embodiments of the invention are evident from the claims and the examples. It will be understood that the features of the subject matter / method / use according to the invention listed above and described below can be used not only in the combination specified in each case but also in other combinations without departing from the scope of the invention. For example, combinations of preferred features with particularly preferred features, or combinations of features not further characterized with particularly preferred features, etc. are implicitly encompassed even if these combinations are not explicitly mentioned.

[0076] Hereinafter, exemplary embodiments of the present invention will be described, but the present invention is not limited thereto. In particular, the present invention also encompasses embodiments resulting from the reference to dependent relationships and therefore combinations specified below. More specifically, when describing a range in the following embodiments, for example, the expression "a method according to any of embodiments 1 to 4" means that any combination of embodiments within this range should be understood to be explicitly disclosed to a person skilled in the art, and the expression should be considered synonymous with "a method according to any of embodiments 1, 2, 3, and 4."

[0077] 1. At least components (i) to (iii): (i) a polyisocyanate composition; (ii) at least one chain extender, and (iii) at least one polyol composition 1. A thermoplastic polyurethane obtained or obtained by converting where: The polyol composition comprises at least one polyol (P1) having a molecular weight Mw in the range of 500 to 2000 g / mol and having at least one aromatic polyester block (B1), The hard segment content in the thermoplastic polyurethane is <75%; Thermoplastic polyurethane.

[0078] 2. The thermoplastic polyurethane according to embodiment 1, wherein the polyol (P1) comprises 20% to 70% by weight of aromatic polyester blocks (B1), based on the total polyester polyol (P1).

[0079] 3. The thermoplastic polyurethane according to any one of the preceding embodiments, wherein the aromatic polyester block (B1) is a polyester of an aromatic dicarboxylic acid and an aliphatic diol.

[0080] 4. The thermoplastic polyurethane according to any one of embodiments 1 to 3, wherein the aromatic polyester block (B1) is a polyethylene terephthalate block or a polybutylene terephthalate block.

[0081] 5. The thermoplastic polyurethane according to any one of embodiments 1 to 4, wherein the aromatic polyester block (B1) is a polyethylene terephthalate block.

[0082] 6. The thermoplastic polyurethane according to any one of the preceding embodiments, wherein the polyol (P1) has a molecular weight Mw in the range of 750 to 1500 g / mol.

[0083] 7. The thermoplastic polyurethane according to any one of the preceding embodiments, wherein the polyol (P1) is obtained from an aromatic polyester having a molecular weight in the range of 10,000 to 14,000 g / mol.

[0084] 8. The thermoplastic polyurethane according to any one of the preceding embodiments, wherein the polyol (P1) is obtained by transesterification from an aromatic polyester having a molecular weight in the range of 10,000 to 14,000 g / mol.

[0085] 9. The thermoplastic polyurethane according to any one of the preceding embodiments, wherein the polyol (P1) is obtained by transesterification from polyethylene terephthalate having a molecular weight in the range of 10,000 to 14,000 g / mol.

[0086] 10. The thermoplastic polyurethane according to any one of the preceding embodiments, wherein the chain extender used in (ii) is a diol having a molecular weight Mw<220 g / mol.

[0087] 11. The thermoplastic polyurethane according to any one of the preceding embodiments, wherein the chain extender used in (ii) and the polyol (P1) present in the polyol composition are used in a molar ratio of 40:1 to 1:10.

[0088] 12. The thermoplastic polyurethane of any one of the preceding embodiments, wherein the polyol composition comprises an additional polyol selected from the group consisting of polyetherols, polyesterols, polycarbonate alcohols, and hybrid polyols.

[0089] 13. The thermoplastic polyurethane of any one of embodiments 1-12, wherein the polyisocyanate is an aliphatic or aromatic diisocyanate.

[0090] 14. The thermoplastic polyurethane of any one of embodiments 1 to 13, wherein the hard segment content in the thermoplastic polyurethane ranges from 10% to 75%.

[0091] 15. A method for producing a compact (SC), comprising the following steps: (a) (i) at least one polyisocyanate composition; (ii) at least one chain extender, and (iii) at least one polyol composition producing a thermoplastic polyurethane comprising the composition of where: The polyol composition comprises at least one polyol (P1) having a molecular weight Mw in the range of 500 to 2000 g / mol and having at least one aromatic polyester block (B1), The hard segment content in thermoplastic polyurethane is <75%; (b) A process for producing a molded body (SC) from thermoplastic polyurethane A method comprising:

[0092] 16. The method according to embodiment 15, wherein the compact (SC) is produced in step (b) by extrusion, injection molding or sintering, or from a solution.

[0093] 17. A shaped body obtainable or obtained by the method according to any one of embodiments 15 and 16.

[0094] 18. The molded article of embodiment 17, wherein the molded article is a consumer article, such as a toothbrush, a razor, a housing for a household item, a display, a computer or telephone part, a plug, an automobile interior part, a footwear part, such as a toe cap for a safety shoe, or the like.

[0095] 19. At least components (i) to (iii): (i) a polyisocyanate composition; (ii) at least one chain extender, and (iii) at least one polyol composition 1. A thermoplastic polyurethane obtained or obtained by converting where: The polyol composition comprises at least one polyol (P1) having a molecular weight Mw in the range of 500 to 2000 g / mol and having at least one aromatic polyester block (B1), The hard segment content in the thermoplastic polyurethane is <75%; The polyol (P1) contains 20% by mass to 70% by mass of the aromatic polyester block (B1) based on the total polyester polyol (P1), Thermoplastic polyurethane, wherein the aromatic polyester block (B1) is a polyethylene terephthalate block or a polybutylene terephthalate block.

[0096] 20. At least the following components (i) to (iii): (i) a polyisocyanate composition; (ii) at least one chain extender, and (iii) at least one polyol composition 1. A thermoplastic polyurethane obtained or obtained by converting where: The polyol composition comprises at least one polyol (P1) having a molecular weight Mw in the range of 500 to 2000 g / mol and having at least one aromatic polyester block (B1), The hard segment content in the thermoplastic polyurethane is in the range of 10% to 75%; A thermoplastic polyurethane, wherein the polyol (P1) contains 20% by mass to 70% by mass of an aromatic polyester block (B1) based on the total polyester polyol (P1), and the aromatic polyester block (B1) is a polyethylene terephthalate block.

[0097] 21. The thermoplastic polyurethane according to any one of embodiments 19 and 20, wherein the polyol (P1) has a molecular weight Mw in the range of 750 to 1500 g / mol.

[0098] 22. The thermoplastic polyurethane according to any one of embodiments 19 to 21, wherein the polyol (P1) is obtained from an aromatic polyester having a molecular weight in the range of 10,000 to 14,000 g / mol.

[0099] 23. The thermoplastic polyurethane according to any one of embodiments 19 to 22, wherein the polyol (P1) is obtained by transesterification from an aromatic polyester having a molecular weight in the range of 10,000 to 14,000 g / mol.

[0100] 24. The thermoplastic polyurethane according to any one of embodiments 19 to 23, wherein the polyol (P1) is obtained by transesterification from polyethylene terephthalate having a molecular weight in the range of 10,000 to 14,000 g / mol.

[0101] 25. The thermoplastic polyurethane according to any one of embodiments 19 to 24, wherein the chain extender used in (ii) is a diol having a molecular weight Mw<220 g / mol.

[0102] 26. The thermoplastic polyurethane according to any one of embodiments 19 to 25, wherein the chain extender used in (ii) and the polyol (P1) present in the polyol composition are used in a molar ratio of 40:1 to 1:10.

[0103] 27. The thermoplastic polyurethane of any one of embodiments 19-26, wherein the polyol composition comprises an additional polyol selected from the group consisting of polyetherols, polyesterols, polycarbonate alcohols, and hybrid polyols.

[0104] 28. The thermoplastic polyurethane of any one of embodiments 19-27, wherein the polyisocyanate is an aliphatic or aromatic diisocyanate.

[0105] 29. The thermoplastic polyurethane of any one of embodiments 19-28, wherein the polyisocyanate is an aromatic diisocyanate.

[0106] 30. A method for producing a compact (SC), comprising the following steps: (a) (i) at least one polyisocyanate composition; (ii) at least one chain extender, and (iii) at least one polyol composition producing a thermoplastic polyurethane comprising the composition of where: The polyol composition comprises at least one polyol (P1) having a molecular weight Mw in the range of 500 to 2000 g / mol and having at least one aromatic polyester block (B1), The hard segment content in the thermoplastic polyurethane is in the range of 10% to 75%; The polyol (P1) contains 20% by mass to 70% by mass of an aromatic polyester block (B1) based on the total polyester polyol (P1), and the aromatic polyester block (B1) is a polyethylene terephthalate block or a polyethylene terephthalate block; (b) A process for producing a molded body (SC) from thermoplastic polyurethane A method comprising:

[0107] 31. The method of embodiment 30, wherein the aromatic polyester block (B1) is a polyethylene terephthalate block.

[0108] 32. The method according to any one of embodiments 30 and 31, wherein the polyol (P1) has a molecular weight Mw in the range of 1700 to 2300 g / mol.

[0109] 33. The method according to any one of embodiments 30 to 32, wherein the chain extender used in (ii) is a diol having a molecular weight Mw<220 g / mol.

[0110] 34. The method according to any one of embodiments 30 to 33, wherein the chain extender used in (ii) and the polyol (P1) present in the polyol composition are used in a molar ratio of 40:1 to 1:10.

[0111] 35. The method according to any one of embodiments 30 to 34, wherein the compact (SC) is produced in step (b) by extrusion, injection molding or sintering, or from a solution.

[0112] 36. A molded article obtained or obtained by the method according to any one of embodiments 30 to 35.

[0113] 37. The molded article of embodiment 36, wherein the molded article is a consumer article, such as a toothbrush, a razor, a housing for a household item, a display, a computer or telephone part, a plug, an automobile interior part, a footwear part, such as a toe cap for a safety shoe, or the like.

[0114] The following examples are intended to illustrate the invention but are not intended to limit the subject matter of the invention in any way. [Example]

[0115] The following raw materials were used:

[0116] Polyol 1: polyester polyol based on adipic acid, PET, butane-1,4-diol and diethylene glycol, OH number 111.2, functionality: 2 Polyol 2: polyester polyol based on adipic acid, PET, butane-1,4-diol and diethylene glycol, OH number 112.8, functionality: 2 Polyol 3: polyester polyol based on adipic acid, PET, butane-1,4-diol and propane-1,3-diol, OH number 112.1, functionality: 2 Polyol 4: Polyester polyol based on adipic acid, succinic acid, glutaric acid, PET and diethylene glycol, OH number 75.6, functionality: 2 Polyol 5: Polyester polyol based on adipic acid, succinic acid, glutaric acid, PET and diethylene glycol, OH number 110.6, functionality: 2 PET: polyethylene terephthalate in flake form, average molecular weight Mw 12000 g / mol Isocyanate 1: Aromatic isocyanate (methylenediphenyl 4,4'-diisocyanate) Isocyanate 2: Aliphatic isocyanate (methylenedicyclohexyl 4,4'-diisocyanate) CE1: Butane-1,4-diol CE2: hexane-1,6-diol Stabilizer 1: Polycarbodiimide-based hydrolysis stabilizer Catalyst 1: 50% tin(II) isooctanoate in diethylhexyl adipate

[0117] 2. Synthesis of polyester polyol containing PET blocks 2.1 Synthesis of polyol 1 A 4000 ml round-bottom flask equipped with a PT100 thermocouple, nitrogen inlet, stirrer, column, column head, Anschutz-Thiele fittings, and heating mantle is initially charged with 880.84 g of adipic acid, 395.56 g of butane-1,4-diol, and 465.79 g of diethylene glycol. This mixture is then heated to 120°C until a homogeneous mixture is formed. Next, 1000 g of polyethylene terephthalate (PET) is added to the mixture in the form of PET flakes, followed by 10 ppm = 2.5 g of TTB (tetra-n-butyl orthotitanate, 1% in toluene). The reaction mixture is first heated to 180°C for approximately 1.5 hours, then further heated to 240°C, continuously removing the resulting water of reaction. Over the entire synthesis, the PET flakes gradually decompose, forming a clear mixture. This is concentrated until a product having an acid number <1.0 mg KOH / g is obtained.

[0118] The polymer obtained has the following properties:

[0119] Hydroxyl number: 111.2 mg KOH / g Acid value: 0.45mgKOH / g Viscosity at 75°C: 757mPas

[0120] 2.2 Synthesis of polyol 2 A 4000 ml round-bottom flask equipped with a PT100 thermocouple, nitrogen inlet, stirrer, column, column head, Anschutz-Thiele fittings, and heating mantle is initially charged with 705.39 g of adipic acid, 339.84 g of butane-1,4-diol, and 400.18 g of diethylene glycol. This mixture is then heated to 120°C until a homogeneous mixture is formed. 1250 g of polyethylene terephthalate (PET) is then added to the mixture in the form of PET flakes, followed by 10 ppm = 2.5 g of TTB (tetra-n-butyl orthotitanate, 1% in toluene). The reaction mixture is first heated to 180°C for approximately 1.5 hours, then further heated to 240°C, continuously removing the resulting water of reaction. Over the entire synthesis, the PET flakes gradually decompose, forming a clear mixture. This is concentrated until a product having an acid number <1.0 mg KOH / g is obtained.

[0121] The polymer obtained has the following properties:

[0122] Hydroxyl number: 112.8 mg KOH / g Acid value: 0.55mgKOH / g Viscosity at 75°C: 1388mPas

[0123] 2.3 Synthesis of polyol 3 A 4000 ml round-bottom flask equipped with a PT100 thermocouple, nitrogen inlet, stirrer, column, column head, Anschutz-Thiele fittings, and heating mantle is initially charged with 788.52 g of adipic acid, 309.27 g of propane-1,3-diol, and 366.24 g of butane-1,4-diol. This mixture is then heated to 120°C until a homogeneous mixture is formed. Next, 1250 g of polyethylene terephthalate (PET) is added to the mixture in the form of PET flakes, followed by 10 ppm = 2.5 g of TTB (tetra-n-butyl orthotitanate, 1% in toluene). The reaction mixture is first heated to 180°C for approximately 1.5 hours, then further heated to 240°C, continuously removing the resulting water of reaction. Over the entire synthesis, the PET flakes gradually decompose, forming a clear mixture. This is concentrated until a product having an acid number <1.0 mg KOH / g is obtained.

[0124] The polymer obtained has the following properties:

[0125] Hydroxyl number: 112.1 mg KOH / g Acid value: 0.38mgKOH / g Viscosity at 75°C: 1803mPas

[0126] 2.4 Synthesis of polyol 4 A 3000 ml round-bottom flask equipped with a thermometer, nitrogen inlet, stirrer, and heating mantle is initially charged with 819.5 g of a dicarboxylic acid mixture (consisting of adipic acid, glutaric acid, and succinic acid) and 925.9 g of diethylene glycol. This mixture is then heated to 120°C until a homogeneous mixture is formed. 1000 g of polyethylene terephthalate (PET) in the form of PET flakes is then added to the mixture. The reaction mixture is further heated at 240°C, and the resulting water of reaction is continuously removed. Over the entire synthesis, the PET flakes are gradually decomposed, forming a clear mixture. This is then condensed until a product having an acid value of <1.0 mg KOH / g is obtained.

[0127] The polymer obtained has the following properties:

[0128] Acid value: 110.6mgKOH / g Hydroxyl number: 0.6 mg KOH / g Viscosity at 75°C: 660mPas

[0129] 2.5 Synthesis of polyol 5 A 3000 ml round-bottom flask equipped with a thermometer, nitrogen inlet, stirrer, and heating mantle is initially charged with 1040.9 g of a dicarboxylic acid mixture (consisting of adipic acid, glutaric acid, and succinic acid) and 1016.2 g of diethylene glycol. This mixture is then heated to 120°C until a homogeneous mixture is formed. 750 g of polyethylene terephthalate (PET) in the form of PET flakes is then added to the mixture. The reaction mixture is further heated at 240°C, and the resulting water of reaction is continuously removed. Over the entire synthesis, the PET flakes are gradually decomposed, forming a clear mixture. This is then condensed until a product having an acid value of <1.0 mg KOH / g is obtained.

[0130] The polymer obtained has the following properties:

[0131] Acid value: 75.6mgKOH / g Hydroxyl number: 0.7 mg KOH / g Viscosity at 75°C: 840mPas

[0132] 3. Method 3.1 Determination of viscosity: Unless otherwise stated, the viscosity of the polyols was measured at 75°C using a Rheotec RC 20 rotational viscometer with a CC 25 DIN spindle (spindle diameter: 12.5 mm; measuring cylinder inner diameter: 13.56 mm) according to DIN EN ISO 3219 (edition 01.10.1994) at a shear rate of 50 (1 / s).

[0133] 3.2 Hydroxyl Number Determination: The hydroxyl number is determined by the phthalic anhydride method DIN 53240 (ed. 01.12.1971) and reported in mg KOH / g.

[0134] 3.3 Acid number determination: The acid number was determined according to DIN EN 1241 (edition 01.05.1998) and is reported in mg KOH / g.

[0135] 4.General manufacturing example The polyol was first placed in a vessel at 60-80°C and mixed with the ingredients listed in Table 1 under vigorous stirring. The reaction mixture was heated to above 80°C and then poured onto a heated Teflon-coated table. The resulting cast slab was heat treated at 80°C for 15 hours, then pelletized and processed by injection molding.

[0136] [Table 1]

[0137] 5. Mechanical properties The measurements summarized in Table 2 were established from the injection molded sheets of Examples 1-5.

[0138] The following properties of the resulting polyurethane were determined by the methods listed below.

[0139] Hardness: DIN ISO 7619-1 Tensile strength and elongation at break: DIN 53504 Tear propagation resistance: DIN ISO 34-1, B(b) Elastic modulus: DIN EN ISO 527 Wear measurement: DIN ISO 4649

[0140] [Table 2]

[0141] In the presence of PET polyol, it is possible to reduce the hard segment content (isocyanate and chain extender) and still achieve high values ​​of Shore D >75 and elongation at break >300%. The materials obtained according to Examples 1 to 5 are all transparent. The examples demonstrate that particularly good properties can be achieved with a PET content in the range of 40% to 50% and an average molecular weight Mw of the polyol of about 1000 g / mol.

[0142] Cited literature US5574092 US5627254 WO2015 / 063062 A1 WO2007 / 118827 A1 Kunststoffhandbuch, Volume 7, “Polyurethane” [Plastics Handbook, Volume 7, Polyurethane], Carl Hanser Verlag, 3rd edition, 1993, Chapter 3.1 Kunststoffhandbuch, Volume 7, Carl Hanser Verlag, 1st edition, 1966, pp. 103-113

Claims

1. At least the following components (i) to (iii): (i) a polyisocyanate composition; (ii) at least one chain extender, and (iii) at least one polyol composition 1. A transparent thermoplastic polyurethane obtained or obtained by converting the polyol composition comprises at least one polyol (P1) having a molecular weight Mw in the range of 500 to 2000 g / mol and having at least one aromatic polyester block (B1), The hard segment content in the thermoplastic polyurethane is <75%; and The chain extender used in (ii) is a diol selected from 1,2-ethylene glycol, propane-1,3-diol, butane-1,4-diol, hexane-1,6-diol, and the chain extender used in (ii) and the polyol (P1) present in the polyol composition are used in a molar ratio of 40:1 to 1:10, and The molecular weight (Mw) of the at least one polyol (P1) is calculated using the following formula, where z is the functionality of the polyester polyol and z=2: Mw = 1000 mg / g [(z 56.106 g / mol) / (OHN [mg / g])], and The aromatic polyester block (B1) is a polyethylene terephthalate block or a polybutylene terephthalate block. A thermoplastic polyurethane characterized by:

2. 2. The thermoplastic polyurethane according to claim 1, wherein the polyol (P1) comprises 20% to 70% by weight of aromatic polyester blocks (B1), based on the total polyester polyol (P1).

3. 3. Thermoplastic polyurethane according to claim 1, wherein the polyol (P1) has a molecular weight Mw in the range of 750 to 1500 g / mol.

4. The thermoplastic polyurethane of any one of claims 1 to 3, wherein the polyol composition comprises a further polyol selected from the group consisting of polyetherols, polyesterols, polycarbonate alcohols, and hybrid polyols.

5. The thermoplastic polyurethane of any one of claims 1 to 4, wherein the polyisocyanate is an aliphatic or aromatic diisocyanate.

6. 6. The thermoplastic polyurethane according to claim 1, wherein the hard segment content in the thermoplastic polyurethane is in the range of 10% to <75%.

7. A method for producing a molded body (SC), comprising the following steps: (a) (i) at least one polyisocyanate composition; (ii) at least one chain extender, and (iii) at least one polyol composition 1. A process for producing a thermoplastic polyurethane comprising the composition of the polyol composition comprises at least one polyol (P1) having a molecular weight Mw in the range of 500 to 2000 g / mol and having at least one aromatic polyester block (B1), a step in which the hard segment content in the thermoplastic polyurethane is <75%; (b) A step of producing a molded body (SC) from thermoplastic polyurethane and The chain extender used in (ii) is a diol selected from 1,2-ethylene glycol, propane-1,3-diol, butane-1,4-diol, hexane-1,6-diol, and the chain extender used in (ii) and the polyol (P1) present in the polyol composition are used in a molar ratio of 40:1 to 1:10, and The molecular weight (Mw) of the at least one polyol (P1) is calculated using the following formula, where z is the functionality of the polyester polyol and z=2: Mw = 1000 mg / g [(z 56.106 g / mol) / (OHN [mg / g])], and The aromatic polyester block (B1) is a polyethylene terephthalate block or a polybutylene terephthalate block. A method characterized by:

8. 8. The method according to claim 7, wherein in step (b) the compact (SC) is produced by extrusion, injection molding or sintering or from solution.

9. 9. The method of claim 7 or 8, wherein the thermoplastic polyurethane is a transparent thermoplastic polyurethane.

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