Articles made from hydrophilic thermoplastic polyurethane compositions

Abstract

To provide an article prepared by injection molding.SOLUTION: An article is prepared by injection molding, where the article is formed from a hydrophilic thermoplastic polyurethane composition, where the thermoplastic polyurethane composition comprises a reaction product of a hydroxyl terminated polyol intermediate component, an aliphatic isocyanate component and optionally a chain extender component. For the injection molding, the hydrophilic thermoplastic polyurethane has a crystallization temperature measured by dynamic scanning calorimetry of at least 75°C.SELECTED DRAWING: None

Description

[Technical field]

[0001] Technical Field The present invention relates to articles made using hydrophilic thermoplastic polyurethane compositions. The articles can be made by injection molding or by 3D printing. [Background technology]

[0002] background Hydrophilic thermoplastic polyurethanes (TPUs) made from aliphatic isocyanates exhibit beneficial properties that make them useful for a variety of articles, but the manufacturing methods for making articles from such TPU materials are somewhat limited. In particular, hydrophilic TPU compositions based on aliphatic isocyanates require commercially unacceptable long processing times, which prevents such materials from being used in certain applications. For example, in injection molding applications or 3D printing applications such as fused deposition modeling, the TPU materials need to solidify sufficiently before they can be handled. Such hydrophilic TPUs based on aliphatic isocyanates typically crystallize at lower temperatures or not at all, and therefore solidify more slowly, resulting in a longer period of time before the article can be removed from the mold or handled after printing, so that such hydrophilic TPUs have longer cycle times. Making articles from these materials using injection molding or 3D printing is not commercially viable due to the long processing times. Therefore, it is necessary to have a hydrophilic TPU based on an aliphatic isocyanate that can be rapidly solidified in a mold so that articles can be made by injection molding or 3D printing. Summary of the Invention [Means for solving the problem]

[0003] Abstract The present invention relates to injection molded or 3D printed articles made from hydrophilic thermoplastic polyurethanes (TPUs), and processes for making such articles.

[0004] In one embodiment of the present invention, the injection molded article comprises a TPU composition, the TPU composition comprising the reaction product of a hydroxyl terminated polyol intermediate component, an isocyanate component comprising an aliphatic diisocyanate, and optionally a chain extender, the TPU composition having a crystallization temperature of at least 75° C. as measured by dynamic scanning calorimetry (DSC). In one embodiment, the TPU composition comprises 10 wt % to about 50 wt % hard segments. In one embodiment, the TPU composition has a water absorption range of at least 100% as measured by ASTM D570 test method. In some embodiments, the chain extender is present and comprises 1,4-butanediol. In some embodiments, the hydroxyl terminated polyol intermediate comprises poly(ethylene glycol).

[0005] In another embodiment, an injection molded article comprises a TPU composition comprising the reaction product of a hydroxyl terminated polyol intermediate component comprising poly(ethylene glycol), an isocyanate component comprising hexamethylene diisocyanate, and a chain extender component, wherein the isocyanate component and the chain extender component constitute the hard segments of the TPU composition, the TPU composition comprises 10 wt % to about 30 wt % hard segments, the TPU composition has a water absorption range of at least 100% as measured by ASTM D570 test method, and the TPU composition has a crystallization temperature of at least 75° C. as measured by DSC. In one such embodiment, the hydroxyl terminated polyol intermediate consists essentially of poly(ethylene glycol). The isocyanate component consists essentially of hexamethylene diisocyanate. It may be, or consist essentially of.

[0006] Another embodiment of the invention includes a method of making an injection molded article comprising the steps of preparing a TPU composition as described herein, wherein the thermoplastic polyurethane composition has a crystallization temperature of at least 75° C. as measured by DSC; heating the thermoplastic polyurethane composition to a temperature of from 160° C. to 190° C. to melt the thermoplastic polyurethane composition; injecting the molten thermoplastic polyurethane composition into a mold; and cooling the thermoplastic polyurethane composition to form an article.

[0007] Another embodiment of the invention includes the use of a TPU composition comprising the reaction product of a hydroxyl-terminated intermediate component, where the hydroxyl-functional intermediate component comprises poly(ethylene glycol), an isocyanate component comprising hexamethylene diisocyanate, and optionally a chain extender component, in injection molding to form an article. In one such embodiment, the chain extender is present and comprises 1,4-butanediol.

[0008] In one embodiment of the present invention, the 3D printed article comprises a TPU composition, the TPU composition comprising the reaction product of a hydroxyl-terminated polyol intermediate component, an isocyanate component comprising an aliphatic diisocyanate, and optionally a chain extender, the TPU composition having a crystallization temperature of at least 75° C. as measured by dynamic scanning calorimetry (DSC). In one embodiment, the TPU composition comprises 10 wt % to about 50 wt % hard segments. In one embodiment, the TPU composition has a water absorption range of at least 100% as measured by ASTM D570 test method. In some embodiments, the chain extender is present and comprises 1,4-butanediol. In some embodiments, the hydroxyl-terminated polyol intermediate comprises poly(ethylene glycol).

[0009] In another embodiment, the 3D printed article comprises a TPU composition, the TPU composition comprising the reaction product of a hydroxyl-terminated polyol intermediate component comprising poly(ethylene glycol), an isocyanate component comprising hexamethylene diisocyanate, and a chain extender component, the isocyanate component and the chain extender component constituting the hard segments of the TPU composition, the TPU composition comprising 10 wt% to about 30 wt% hard segments, the TPU composition having a water absorption range of at least 100% as measured by ASTM D570 test method, and the TPU composition having a crystallization temperature of at least 75°C as measured by DSC. In one such embodiment, the hydroxyl-terminated polyol intermediate consists essentially of poly(ethylene glycol). The isocyanate component may consist essentially of hexamethylene diisocyanate.

[0010] Another embodiment of the invention includes a method of making a 3D printed article, the method comprising operating a system for solid freeform fabrication of an object, the system comprising a solid freeform fabrication apparatus that deposits small beads of build material in a controlled manner to form a three dimensional article, the build material comprising a TPU composition, the TPU composition comprising the reaction product of a hydroxyl terminated polyol intermediate component, an isocyanate component comprising an aliphatic diisocyanate, and optionally a chain extender, the TPU composition having a crystallization temperature of at least 75° C. as measured by dynamic scanning calorimetry (DSC).

[0011] Another embodiment of the invention is a solid freeform fabrication machine hot melt product for forming an article of a TPU composition comprising a reaction product of a hydroxyl-terminated intermediate component, the hydroxyl-functional intermediate component comprising a poly(ethylene glycol), an isocyanate component comprising hexamethylene diisocyanate, and optionally a chain extender component. In one such embodiment, the chain extender is present and comprises 1,4-butanediol. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Detailed Description Injection molded or 3D printed articles according to the present invention are made using a TPU composition comprising the reaction product of a hydroxyl terminated intermediate component, an isocyanate component comprising an aliphatic diisocyanate, and optionally a chain extender component. In one aspect of the present invention, the thermoplastic polyurethane composition has a crystallization temperature as measured by DSC of at least 75°C so that the thermoplastic polyurethane composition can be effectively injection molded or used in a solid freeform fabrication system (3D printing). The TPU composition of the present invention can also have a water absorption range of at least 100% as measured by ASTM D570. The TPU composition can also have a hard segment (defined as the amount of isocyanate alone or a combination of isocyanate and chain extender) of 10 wt% to 50 wt%, for example 13 wt% to 30 wt%. Hydroxyl-Terminated Intermediate Components

[0013] The TPU compositions described herein are made using hydroxyl-terminated polyol intermediates. The polyols include polyether polyols, polyester polyols, polycarbonate polyols, polysiloxane polyols, and combinations thereof.

[0014] In one useful embodiment, the hydroxyl-terminated polyol intermediate comprises a polyether polyol intermediate. Hydroxyl-terminated polyether intermediate comprises a polyether polyol derived from a diol or polyol having a total of 2 to 15 carbon atoms, an alkyl diol or glycol having 2 to 6 carbon atoms in some embodiments reacted with an ether comprising an alkylene oxide, typically ethylene oxide or propylene oxide or mixtures thereof. For example, a hydroxyl-functional polyether can be produced by first reacting propylene glycol with propylene oxide, followed by subsequent reaction with ethylene oxide. Primary hydroxyl groups resulting from ethylene oxide are more reactive than secondary hydroxyl groups and are therefore preferred. Useful commercially available polyether polyols include poly(ethylene glycol) comprising ethylene oxide reacted with ethylene glycol, poly(propylene glycol) comprising propylene oxide reacted with propylene glycol, poly(tetramethylene ether glycol) comprising water reacted with tetrahydrofuran, which may also be described as polymerized tetrahydrofuran and is commonly referred to as PTMEG. Polyether polyols may also include polyamide adducts of alkylene oxides, such as ethylenediamine adducts including the reaction product of ethylenediamine and propylene oxide, diethylenetriamine adducts including the reaction product of diethylenetriamine and propylene oxide, and similar polyamide-type polyether polyols. Copolyethers may also be utilized in the described compositions. Exemplary copolyethers include the reaction products of THF and ethylene oxide or THF and propylene oxide. These are available from BASF as PolyTHF® B, a block copolymer, and PolyTHF® R, a random copolymer. The various polyether intermediates generally have number average molecular weights (Mn), as determined by assay of the terminal functional groups, of greater than about 700, such as from about 700 to about 10,000, or from about 1,000 to about 8,000, or from about 1,400 to about 8,000.

[0015] In some embodiments, the hydroxyl-terminated polyol intermediate used to make the TPU compositions of the present invention comprises a poly(ethylene glycol) having an Mn of about 1,000 to about 10,000. In some embodiments, the hydroxyl-terminated polyol intermediate consists essentially of poly(ethylene glycol) having a Mn of about 1,000 to about 10,000. Isocyanate component

[0016] The TPU composition described herein is made using a) polyisocyanate component. In particular, the polyisocyanate component useful in the present invention is an aliphatic diisocyanate. Examples of aliphatic polyisocyanates include isophorone diisocyanate (IPDI), 1,4-cyclohexyl diisocyanate (CHDI), decane-1,10-diisocyanate, lysine diisocyanate (LDI), 1,4-butane diisocyanate (BDI), 1,5-pentane diisocyanate (PDI), hydrogenated xylene diisocyanate (HXDI), isophorone diisocyanate, hexamethylene diisocyanate (HDI) and dicyclohexylmethane-4,4'-diisocyanate (H12MDI). A mixture of two or more polyisocyanates may be used.

[0017] In any embodiment of the present invention, the polyisocyanate component may consist or consist essentially of hexamethylene diisocyanate. Chain extender component

[0018] The TPU compositions described herein are optionally made using a chain extender component. Chain extenders include diols, diamines, and combinations thereof.

[0019] Suitable chain extenders include relatively low molecular weight polyhydroxy compounds, such as lower aliphatic or short chain glycols having 2 to 20, or 2 to 12, or 2 to 10 carbon atoms. Suitable examples include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol (BDO), 1,6-hexanediol (HDO), 1,3-butanediol, 1,5-pentanediol, neopentyl glycol, 1,4-cyclohexanedimethanol (CHDM), 2,2-bis[4-(2-hydroxyethoxy)phenyl]propane (HEPP), hexamethylenediol, heptanediol, nonanediol, dodecanediol, 3-methyl-1,5-pentanediol, ethylenediamine, butanediamine, hexamethylenediamine, and hydroxyethylresorcinol (HER), and the like, and mixtures thereof. In some embodiments, the chain extender comprises BDO, HDO, 3-methyl-1,5-pentanediol, or a combination thereof. In some embodiments, the chain extender comprises BDO. Other glycols, such as aromatic glycols, may be used, but in some embodiments, the TPUs described herein are essentially free, or even completely free, of such materials.

[0020] The chain extender, when present, combines with the isocyanate component to form what is known as the "hard segment" of the thermoplastic polyurethane composition. When the chain extender is not present, the "hard segment" is formed solely by the isocyanate component. In some embodiments, the TPU composition of the present invention comprises at least 10 wt% hard segment. In another embodiment, the TPU composition of the present invention comprises 10 wt% to 50 wt% hard segment. In another embodiment, the TPU composition of the present invention comprises 10 wt% to 50 wt% hard segment and has a crystallization temperature of at least 75°C as measured by DSC. In one embodiment, the TPU composition comprises 10 wt% to 30 wt% hard segment and has a water absorption range of at least 100% as measured by ASTM D570. In another embodiment, the TPU composition comprises 10 wt% to 30 wt% hard segment and has a water absorption range of at least 100% as measured by ASTM D570. In another embodiment, the TPU composition comprises at least 13 wt. % hard segment and at least 75° C. crystallization temperature as measured by DSC. It has a water absorption range of at least 100% and a crystallization temperature of at least 75° C. as measured by DSC.

[0021] To prepare the thermoplastic polyurethane composition, three reactants (polyol intermediate, diisocyanate, and chain extender) are reacted together to form the TPU useful in the present invention. Any known process for reacting three reactants to make the TPU may be used. In one embodiment, the process is a so-called "one shot" process, where all three reactants are added to an extrusion reactor and reacted. The equivalents of diisocyanate to the total equivalents of the hydroxyl-containing components, i.e., polyol intermediate and chain extender glycol, may be from about 0.95 to about 1.10, or from about 0.96 to about 1.02, or even from about 0.97 to about 1.005. The reaction temperature utilizing a urethane catalyst may be from about 175 to about 245°C, or in another embodiment, from 180 to 220°C.

[0022] TPUs may also be prepared utilizing a prepolymer process. In the prepolymer route, a polyol intermediate is generally reacted with an equivalent excess of one or more diisocyanates to form a prepolymer solution having free or unreacted diisocyanates therein. The reaction is generally carried out at a temperature of about 80 to about 220°C, or about 150 to about 200°C, in the presence of a suitable urethane catalyst. A chain extender is then added, as described above, in an amount generally equal to the isocyanate end groups and any free or unreacted diisocyanate compounds. Thus, the overall equivalent ratio of total diisocyanates to total equivalents of polyol intermediate and chain extender is about 0.95 to about 1.10, or about 0.96 to about 1.02, or even about 0.97 to about 1.05. The chain extension reaction temperature is generally about 180 to about 250°C, or about 200 to about 240°C. Typically, the prepolymer route can be carried out in any conventional device, including an extruder. In such an embodiment, the polyol intermediate is reacted with an equivalent excess of diisocyanate in a first section of the extruder to form a prepolymer solution, and then a chain extender is added in a downstream section and reacted with the prepolymer solution. Any conventional extruder can be utilized, including extruders equipped with a barrier screw having a length-to-diameter ratio of at least 20, and in some embodiments at least 25.

[0023] In one embodiment, the components are mixed in a single or twin screw extruder having multiple heating zones and multiple feed ports between its feed end and die end. The components may be added at one or more of the feed ports, and the resulting TPU composition exiting the die end of the extruder may be pelletized.

[0024] The preparation of various polyurethanes according to conventional procedures and methods, and generally for any type of polyurethane available as described above, the various amounts of specific components thereof, the various reactant ratios, processing temperatures, catalysts in their amounts, polymerization equipment such as extruders of various kinds, etc. are all generally conventional and well known in the art and literature.

[0025] The described processes for preparing the TPU of the present invention include both "prepolymer" and "one-shot" processes, either batchwise or continuous. That is, in some embodiments, the TPU may be made by reacting the components together in a "one-shot" polymerization process, where all of the components, including the reactants, are added together at the same time or substantially at the same time to a heated extruder and reacted to form the TPU. Meanwhile, in other embodiments, the TPU may be made by first reacting the polyisocyanate component with a portion of the polyol component to form a prepolymer, and then reacting the prepolymer with the remaining reactants to complete the reaction to produce the TPU.

[0026] After exiting the extruder, the composition is typically pelletized, stored in moisture-proof packaging, and ultimately sold in pellet form. The composition does not necessarily have to be pelletized, and may be extruded from the reaction extruder. It will be appreciated that the composition may be directly extruded from the die as the final product profile.

[0027] During the polymerization reaction, one or more polymerization catalysts may be present. In general, any conventional catalyst may be utilized to react diisocyanates with polyol intermediates or chain extenders. Examples of suitable catalysts that specifically promote the reaction between the NCO groups of diisocyanates and the hydroxy groups of polyols and chain extenders are conventional tertiary amines known from the prior art, such as triethylamine, dimethylcyclohexylamine, N-methylmorpholine, N,N'-dimethylpiperazine, 2-(dimethylaminoethoxy)ethanol, diazabicyclo[2.2.2]octane, etc., and in particular organometallic compounds, such as titanic acid esters, iron compounds, such as iron acetylacetonate, tin compounds, such as tin diacetate, tin dioctoate, tin dilaurate, or dialkyltin salts of aliphatic carboxylic acids, such as dibutyltin diacetate, dibutyltin dilaurate, etc. The catalyst is usually used in an amount of 0.0001 to 0.1 parts by weight per 100 parts by weight of the polyhydroxy compound (b). Additives

[0028] A wide variety of optional components may be present during the polymerization reaction and / or incorporated within the TPU elastomers described above to improve processing and other properties. These additives include, but are not limited to, antioxidants such as phenolic, organic phosphites, phosphines and phosphonites, hindered amines, organic amines, organic sulfur compounds, lactones and hydroxylamine compounds, biocides, fungicides, antimicrobials, compatibilizers, electrically dissipative or antistatic additives, fillers and reinforcing agents such as titanium dioxide, alumina, clays and carbon black, flame retardants such as phosphates, halogenated materials and metal salts of alkylbenzene sulfonates, impact modifiers such as methacrylate-butadiene-styrene ("MBS") and methyl methacrylate butyl acrylate ("MBA"), release agents such as waxes, fats and oils, pigments and colorants, plasticizers, polymers, rheology modifiers such as monoamines, polyamide waxes, silicones, and polysiloxanes, slip additives such as paraffin waxes, hydrocarbon polyolefins and / or fluorinated polyolefins, and UV stabilizers which may be of the hindered amine light stabilizer (HALS) and / or UV light absorber (UVA) type. Other additives may be used to enhance the performance of the TPU composition or blended product. All of the additives mentioned above may be used in effective amounts customary for these materials.

[0029] These additional additives may be incorporated into the components of the TPU resin, into the reaction mixture for its preparation, or after the TPU resin is made. In an alternative process, the materials may all be mixed with the TPU resin and then melted, or they may be incorporated directly into the melt of the TPU resin.

[0030] In one embodiment, a release agent may be added to the TPU described herein and / or to the mold to reduce adhesion between the mold and the TPU. As release agents, it is possible to use customary substances, such as those described in "Kunststoffhandbuch, Vol. 7, Polyurethane", Carl Hanser Verlag, 3rd Edition, 1993, Chapter 3.4.9. It is particularly preferred to use waxes, fats and / or oils as release agents.

[0031] All the above-mentioned additives can be used in the conventional effective amounts for these materials. These additional additives can be incorporated into the components of the TPU composition, or into the reaction mixture for its preparation, or after the TPU composition is made. In another process, the materials can all be mixed with the TPU composition and then melted, or they can be directly incorporated into the melt of the TPU composition.

[0032] The TPU compositions described herein can be prepared by a process comprising reacting an isocyanate component described herein, a hydroxyl-terminated polyol component described herein, and, optionally, a chain extender component described herein, wherein the reaction is conducted in the presence of a catalyst, the catalyst comprising one or more compounds selected from tin or iron compounds, to provide a thermoplastic polyurethane composition.

[0033] The process may further include mixing the TPU composition with one or more blend components including one or more additional TPU materials and / or polymers, including any of those described above.

[0034] The process may further comprise the step of mixing the TPU composition of step with one or more of the additional additives mentioned above.

[0035] The process may further comprise mixing the TPU composition of step (I) with one or more blend components comprising one or more additional TPU materials and / or polymers including any of those described above, and / or mixing the TPU composition of step (I) with one or more of the additional additives described above.

[0036] The composition of the present invention or any blend thereof can also be used to manufacture the molded product of the present invention in any molding process.The molding process is well known to those skilled in the art and includes, but is not limited to, casting, cold molding, matched die molding, compression molding, foam molding, injection molding, gas-assisted injection molding, profile coextrusion, profile extrusion, rotational molding, sheet extrusion, slush molding, spraying techniques, thermoforming, transfer molding, vacuum forming, wet lamination or contact molding, blow molding, extrusion blow molding, injection blow molding, and injection stretch blow molding, or combinations thereof.

[0037] The TPU composition of the present invention is unexpectedly useful in an injection molding process. In an injection molding process, a molded article can be fabricated by injecting a molten polymer into a mold that shapes and solidifies the molten polymer into a molded article of a desired geometry and thickness. An example of an injection molding process is described as follows: A shaped laminate is placed into an injection molding tool. The mold is closed. The TPU composition of the present invention is melted and injected into the mold. To melt the TPU composition, the TPU composition can be heated to about 160°C to about 190°C. The molten TPU composition can be injected into the mold at an injection speed between 2 and 10 seconds. After injection, the material is consolidated or held for a predetermined time and pressure to dimensionally and aesthetically correct the part. A typical total molding cycle time is about 20 to about 70 seconds, and the pressure is 1,380 to 10,400 kPa. The mold is cooled to between 10°C to 70°C to cool the substrate. The temperature depends on the desired gloss and the desired appearance. Typical cooling times are 10 to 40 seconds, for example 10 to 30 seconds, depending on the thickness of the part. Finally, the mold is opened and the shaped composite article is removed.

[0038] The TPU composition of the present invention is also unexpectedly useful in 3D printing systems (solid freeform fabrication), particularly fused deposition modeling systems. The TPU compositions described herein are ideal for efficient article creation using fused deposition modeling systems. Various types of solid freeform fabrication systems and devices are known in the art. The TPU compositions of the present invention can be used with various types of solid freeform fabrication systems and devices. For example, in one embodiment, a fused deposition modeling system includes a system that builds a part layer by layer by heating a build material to a semi-liquid state and extruding it according to a computer-controlled path. The material may be dispensed from a dispenser as a semi-continuous stream and / or as a filament of material, or alternatively, as individual droplets or beads. Fused deposition modeling can sometimes use two different materials to build an object. The TPU compositions described herein can be used in a variety of applications, including 3D printing, solid freeform fabrication, and solid freeform fabrication. A laminate material, such as a TPU composition, is used in the article. The laminate material may be deposited on a support material, which may act as a "scaffold" for the laminate material. In one embodiment, a filament of material is fed from a material reservoir in the system to a print head, which moves in a two-dimensional plane, depositing material to complete each layer before the base moves along a third axis to a new level and / or plane to begin the next layer. Once the system has completed the build, the user can remove the support material, or even melt it, leaving the finished article. In one embodiment, a fused deposition modeling machine deposits tiny beads of the TPU composition described herein in a controlled manner to form a 3D printed article.

[0039] The TPU composition of the present invention and any blends thereof may also be formed as monolayer or multilayer films, including breathable films. These films may be formed by any of the conventional techniques known in the art, including extrusion, coextrusion, extrusion coating, lamination, blow and cast, or any combination thereof. The films may be obtained by flat film or tubular processes, followed by orientation in one direction in the plane of the film or in two directions perpendicular to each other. One or more of the layers of the film may be oriented to the same or different extents in the transverse and / or longitudinal directions. This orientation may be performed before or after the individual layers are brought together. Typically, the film is oriented in the machine direction (MD) at a ratio of up to 15, preferably between 5 and 7, and in the cross direction (TD) at a ratio of up to 15, preferably between 7 and 9. However, in another embodiment, the film is oriented to the same extent in both the MD and TD directions.

[0040] The TPU compositions described herein can be used in a wide range of injection molded articles where the properties of aliphatic TPU compositions and / or hydrophilic TPUs are desirable. Some examples of useful applications include, but are not limited to, sports and recreational equipment, shoes, such as insoles and soles, medical devices, such as implantable devices, including pacemaker leads, artificial hearts, heart valves, stent covers, artificial tendons, arteries, veins, films containing pharma- ceutical active agents, blood bags, ostomy bags, IV bags, and the like. Injection molded articles using the TPU compositions of the present invention may also include medical tubing and films. The TPU compositions described herein can make the articles waterproof, breathable, or both.

[0041] The TPU compositions of the present invention may also be used to form filaments or fibers, such as by electrospinning, force spinning, or even extrusion spinning. EXAMPLES

[0042] Thermoplastic polyurethane compositions were made using the listed polyols and isocyanates along with 1,4-butanediol chain extender. The isocyanate and chain extender components make up the hard segments. [Table 1]

[0043] Table 1 shows that the combination of HDI and polyethylene glycol at at least 10 wt% of the hard segment results in a TPU composition with the necessary crystallization temperature for an efficient injection molding process. Examples B1, C1, D1, E1, and F1 are examples of the present invention, while A1, A2, B2, C2, D2, E2, and F2 are comparative examples. A lower crystallization temperature means that the TPU composition takes longer to solidify and be removed from the mold. The composition of the present invention provides a suitable material for making injection molded articles from TPU compositions that use aliphatic isocyanates and are hydrophilic. Furthermore, as can be confirmed by comparing Examples B1 and B2, C1 and C2, and D1 and D2, the samples of the present invention made with HDI (B1, C1, and D1) have faster molding times than similar TPUs made with H12MDI.

[0044] As used herein, "including," "containing," or " The transitional term "comprising," which is synonymous with "characterized thereby," is inclusive or open-ended and does not exclude additional unrecited elements or method steps. However, in each recitation of "comprising" herein, it is intended that the term also encompasses the phrases "consisting essentially of" and "consisting of" as alternative embodiments, with "consisting of" excluding any unspecified element or step, and "consisting essentially of" permitting the inclusion of additional unrecited elements or steps that do not materially affect the essential or basic and novel characteristics of the composition or method under consideration. As used herein, measurements referred to as made by "DSC" refer to dynamic scanning calorimetry using a Perkin Elmer DSC7.

[0045] While certain representative embodiments and details have been shown for the purpose of illustrating the present invention, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention, which is limited only by the claims.

[0046] According to a preferred embodiment of the present invention, for example, the following is provided: (Section 1) 1. An injection molded article comprising a thermoplastic polyurethane composition comprising the reaction product of a hydroxyl terminated intermediate component, an isocyanate component comprising an aliphatic diisocyanate, and an optional chain extender component, said thermoplastic polyurethane composition having a crystallization temperature of at least 75° C. as measured by DSC, said isocyanate component and optional chain extender component constituting hard segments of said thermoplastic polyurethane, said thermoplastic polyurethane comprising at least 10 wt % hard segments. (Section 2) 2. The injection-molded article according to claim 1, wherein the thermoplastic polyurethane comprises about 10 wt% to about 50 wt% of a hard segment. (Section 3) 3. The injection-molded article according to any one of items 1 to 2, wherein the thermoplastic polyurethane has a water absorption range of at least 70% as measured by ASTM D570. (Section 4) 4. The injection-molded article according to any one of items 1 to 3, wherein the thermoplastic polyurethane has a water absorption range of at least 100% as measured by ASTM D570. (Section 5) 5. The injection molded article of any one of claims 1 to 4, wherein the polyether polyol intermediate comprises poly(ethylene glycol). (Section 6) 6. The injection molded article according to any one of claims 1 to 5, wherein the diisocyanate comprises one or more diisocyanates selected from the group consisting of isophorone diisocyanate (IPDI), 1,4-cyclohexyl diisocyanate (CHDI), decane-1,10-diisocyanate, lysine diisocyanate (LDI), 1,4-butane diisocyanate (BDI), 1,5-pentane diisocyanate (PDI), hydrogenated xylene diisocyanate (HXDI), isophorone diisocyanate, and hexamethylene diisocyanate (HDI). (Section 7) 7. The injection-molded article of any one of claims 1 to 6, wherein the diisocyanate consists essentially of hexamethylene diisocyanate. (Section 8) the polyether polyol intermediate consists essentially of poly(ethylene glycol); 8. The injection-molded article of any one of claims 1 to 7, wherein the diisocyanate consists essentially of hexamethylene diisocyanate. (Section 9) 1. A method of making an injection molded article, comprising: preparing a thermoplastic polyurethane composition comprising a hydroxyl-terminated intermediate component, an isocyanate component comprising an aliphatic diisocyanate, and an optional chain extender component, said thermoplastic polyurethane composition having a crystallization temperature of at least 75° C. as measured by DSC, said isocyanate component and optional chain extender component constituting hard segments of said thermoplastic polyurethane, said thermoplastic polyurethane comprising at least 10 wt % hard segments; heating the thermoplastic polyurethane composition to a temperature of 120°C to 190°C to melt the thermoplastic polyurethane composition; injecting the molten thermoplastic polyurethane composition into a mold; cooling the thermoplastic polyurethane composition to form an article. A method comprising: (Section 10) 10. The method of claim 9, wherein the hydroxyl-terminated intermediate component comprises poly(ethylene glycol) and the isocyanate component comprises one or more diisocyanates selected from the group consisting of isophorone diisocyanate (IPDI), 1,4-cyclohexyl diisocyanate (CHDI), decane-1,10-diisocyanate, lysine diisocyanate (LDI), 1,4-butane diisocyanate (BDI), 1,5-pentane diisocyanate (PDI), hydrogenated xylene diisocyanate (HXDI), isophorone diisocyanate, and hexamethylene diisocyanate (HDI). (Section 11) 11. The method according to item 9 or 10, wherein the isocyanate component and the optional chain extender component constitute hard segments of the thermoplastic polyurethane, and the thermoplastic polyurethane contains at least 10 wt% to about 50 wt% of hard segments. (Section 12) 12. The method according to claim 11, wherein the thermoplastic polyurethane comprises about 10 wt % to about 30 wt % of a hard segment. (Section 13) 13. The method according to any one of items 9 to 12, wherein the thermoplastic polyurethane has a water absorption range of at least 70% as measured by ASTM D570. (Section 14) 14. The method according to any one of items 9 to 13, wherein the thermoplastic polyurethane has a water absorption range of at least 100% as measured by ASTM D570. (Section 15) 15. The method of any one of claims 9 to 14, wherein the polyether polyol intermediate consists essentially of poly(ethylene glycol). (Section 16) 16. The method of any one of claims 9 to 15, wherein the diisocyanate consists essentially of hexamethylene diisocyanate. (Section 17) 1. An injection molded article comprising a thermoplastic polyurethane composition, the thermoplastic polyurethane composition comprising a reaction product of a hydroxyl-terminated intermediate component, the hydroxyl-functional intermediate component comprising poly(ethylene glycol), an isocyanate component comprising hexamethylene diisocyanate, and a chain extender component, the isocyanate component and the chain extender component constituting hard segments of the thermoplastic polyurethane, the thermoplastic polyurethane composition comprising 10 wt % to about 30 wt % hard segments, the thermoplastic polyurethane composition having a hard segment viscosity measured by ASTM D570. An injection molded article having a water absorption range of at least 100%, said thermoplastic polyurethane composition having a crystallization temperature of at least 75°C as measured by DSC. (Section 18) 1. Use of a thermoplastic polyurethane composition comprising the reaction product of a hydroxyl-terminated intermediate component, said hydroxyl-functional intermediate component comprising poly(ethylene glycol), an isocyanate component comprising hexamethylene diisocyanate, and optionally a chain extender component, in injection molding to form an article. (Section 19) Item 19. Use of the thermoplastic polyurethane composition according to item 18, wherein the thermoplastic polyurethane composition has a crystallization temperature of at least 75°C as measured by DSC. (Section 20) Item 21. Use of the thermoplastic polyurethane composition according to item 18 or 19, wherein the isocyanate component and the optional chain extender component constitute the hard segments of the thermoplastic polyurethane, and the thermoplastic polyurethane contains at least 10 wt % of the hard segments. 21. Use of a thermoplastic polyurethane composition according to any one of claims 18 to 20, wherein the thermoplastic polyurethane comprises from about 10 wt% to about 50 wt% of hard segments. (Section 22) 22. Use of the thermoplastic polyurethane composition according to any one of items 18 to 21, wherein the thermoplastic polyurethane has a water absorption range of at least 70% as measured by ASTM D570. (Section 23) 23. The use of the thermoplastic polyurethane composition according to any one of items 18 to 22, wherein the thermoplastic polyurethane has a water absorption range of at least 100% as measured by ASTM D570. (Section 24) 24. Use of the thermoplastic polyurethane composition according to any one of paragraphs 18 to 23, wherein the polyether polyol intermediate consists essentially of poly(ethylene glycol). (Section 25) 25. Use of the thermoplastic polyurethane composition according to any one of claims 18 to 24, wherein the diisocyanate consists essentially of hexamethylene diisocyanate. (Section 26) 1. A 3D printed article comprising a thermoplastic polyurethane composition, the thermoplastic polyurethane composition comprising the reaction product of a hydroxyl-terminated intermediate component, an isocyanate component comprising an aliphatic diisocyanate, and optionally a chain extender component, the thermoplastic polyurethane composition having a crystallization temperature of at least 75°C as measured by DSC. (Section 27) 27. The 3D printed article of claim 26, wherein the isocyanate component and optional chain extender component constitute hard segments of the thermoplastic polyurethane, the thermoplastic polyurethane comprising at least 10 wt.% hard segments. (Section 28) 27. The 3D printed article of claim 26, wherein the thermoplastic polyurethane comprises about 10 wt% to about 50 wt% of a hard segment. (Section 29) 30. The 3D printed article of any one of claims 26 to 28, wherein the thermoplastic polyurethane has a water absorption range of at least 70% as measured by ASTM D570. (Section 30) 30. The 3D printed article of any one of claims 26 to 29, wherein the thermoplastic polyurethane has a water absorption range of at least 100% as measured by ASTM D570. (Section 31) 31. The 3D printed article of any one of claims 26 to 30, wherein the polyether polyol intermediate comprises poly(ethylene glycol). (Section 32) 32. The 3D printed article according to any one of claims 26 to 31, wherein the diisocyanate comprises one or more diisocyanates selected from the group consisting of isophorone diisocyanate (IPDI), 1,4-cyclohexyl diisocyanate (CHDI), decane-1,10-diisocyanate, lysine diisocyanate (LDI), 1,4-butane diisocyanate (BDI), 1,5-pentane diisocyanate (PDI), hydrogenated xylene diisocyanate (HXDI), isophorone diisocyanate, and hexamethylene diisocyanate (HDI). (Section 33) 33. The 3D printed article of any one of claims 26 to 32, wherein the polyether polyol intermediate consists essentially of poly(ethylene glycol) and the diisocyanate consists essentially of hexamethylene diisocyanate. (Section 34) 1. A method of making a 3D print, comprising: preparing a thermoplastic polyurethane composition comprising a hydroxyl-terminated intermediate component, an isocyanate component comprising an aliphatic diisocyanate, and an optional chain extender component, said thermoplastic polyurethane composition having a crystallization temperature of at least 75° C. as measured by DSC, said isocyanate component and optional chain extender component constituting hard segments of said thermoplastic polyurethane, said thermoplastic polyurethane comprising at least 10 wt % hard segments; operating a system for solid freeform fabrication of an object, said system comprising a solid freeform fabrication device that deposits microscopic beads of a build material in a controlled manner; Including, The method, wherein the build material comprises the thermoplastic polyurethane composition. (Section 35) 35. The method of claim 34, wherein the hydroxyl-terminated intermediate component comprises poly(ethylene glycol) and the isocyanate component comprises one or more diisocyanates selected from the group consisting of isophorone diisocyanate (IPDI), 1,4-cyclohexyl diisocyanate (CHDI), decane-1,10-diisocyanate, lysine diisocyanate (LDI), 1,4-butane diisocyanate (BDI), 1,5-pentane diisocyanate (PDI), hydrogenated xylene diisocyanate (HXDI), isophorone diisocyanate, and hexamethylene diisocyanate (HDI). (Section 36) 36. The method according to item 34 or 35, wherein the isocyanate component and the optional chain extender component constitute hard segments of the thermoplastic polyurethane, and the thermoplastic polyurethane contains at least 10 wt% to about 50 wt% of hard segments. (Section 37) 37. The method according to claim 36, wherein the thermoplastic polyurethane comprises about 10 wt% to about 30 wt% of a hard segment. (Section 38) 38. The method according to any one of claims 34 to 37, wherein the thermoplastic polyurethane has a water absorption range of at least 70% as measured by ASTM D570. (Section 39) 39. The method according to any one of claims 34 to 38, wherein the thermoplastic polyurethane has a water absorption range of at least 100% as measured by ASTM D570. (Section 40) 37. The method of any of claims 34 to 36, wherein the polyether polyol intermediate consists essentially of poly(ethylene glycol). (Section 41) 41. The method of any one of claims 34 to 40, wherein the diisocyanate consists essentially of hexamethylene diisocyanate. (Section 42) 1. A three dimensional printed article comprising a thermoplastic polyurethane composition, the thermoplastic polyurethane composition comprising a reaction product of a hydroxyl-terminated intermediate component, the hydroxyl-functional intermediate component comprising poly(ethylene glycol), an isocyanate component comprising hexamethylene diisocyanate, and a chain extender component, the isocyanate component and the chain extender component constituting hard segments of the thermoplastic polyurethane, the thermoplastic polyurethane composition comprising from 10 wt % to about 30 wt % hard segments, the thermoplastic polyurethane composition having a water absorption range of at least 100% as measured by ASTM D570, and the thermoplastic polyurethane composition having a crystallization temperature of at least 75° C. as measured by DSC. (Section 43) 1. Use of a thermoplastic polyurethane composition comprising the reaction product of a hydroxyl-terminated intermediate component, said hydroxyl-functional intermediate component comprising poly(ethylene glycol), an isocyanate component comprising one or more diisocyanates selected from the group consisting of isophorone diisocyanate (IPDI), 1,4-cyclohexyl diisocyanate (CHDI), decane-1,10-diisocyanate, lysine diisocyanate (LDI), 1,4-butane diisocyanate (BDI), 1,5-pentane diisocyanate (PDI), hydrogenated xylene diisocyanate (HXDI), isophorone diisocyanate, and hexamethylene diisocyanate (HDI), and optionally a chain extender component, in a solid freeform fabrication apparatus to form an article. (Section 44) 44. Use of the thermoplastic polyurethane composition according to claim 43, wherein the thermoplastic polyurethane composition has a crystallization temperature of at least 75°C as measured by DSC. (Section 45) Item 46. Use of the thermoplastic polyurethane composition according to item 43 or 44, wherein the isocyanate component and the optional chain extender component constitute the hard segments of the thermoplastic polyurethane, and the thermoplastic polyurethane contains at least 10 wt % of the hard segments. 46. ​​The use of a thermoplastic polyurethane composition according to any one of items 43 to 45, wherein the thermoplastic polyurethane comprises about 10 wt% to about 50 wt% of a hard segment. (Section 47) 47. Use of the thermoplastic polyurethane composition according to any one of paragraphs 43 to 46, wherein the thermoplastic polyurethane has a water absorption range of at least 70% as measured by ASTM D570. (Section 48) 47. Use of the thermoplastic polyurethane composition according to any one of paragraphs 43 to 46, wherein the thermoplastic polyurethane has a water absorption range of at least 100% as measured by ASTM D570. (Section 49) 49. Use of a thermoplastic polyurethane composition according to any one of paragraphs 43 to 48, wherein the polyether polyol intermediate consists essentially of poly(ethylene glycol). (Section 50) 50. The use of a thermoplastic polyurethane composition according to any one of claims 43 to 49, wherein the diisocyanate consists essentially of hexamethylene diisocyanate.

Claims

1. 1. An injection molded article comprising a thermoplastic polyurethane composition, the thermoplastic polyurethane composition comprising the reaction product of a hydroxyl-terminated intermediate component that is a hydroxyl-terminated polyol, the hydroxyl-terminated intermediate component comprising poly(ethylene glycol), an isocyanate component comprising hexamethylene diisocyanate (HDI), and a chain extender component, wherein the chain extender component is 1,4-butanediol, the isocyanate component and the chain extender component constitute hard segments of the thermoplastic polyurethane, the thermoplastic polyurethane comprising 10 wt % to 50 wt % hard segments.

2. 10. The injection molded article of claim 1, wherein the thermoplastic polyurethane has a water absorption range of at least 70% as measured by ASTM D570 modified by using specimen dimensions of 6.35 cm x 0.1524 cm and an immersion time of 72 hours.

3. 3. The injection molded article of claim 1 or 2, wherein the thermoplastic polyurethane has a water absorption range of at least 100% as measured by ASTM D570 modified by using specimen dimensions of 6.35 cm x 0.1524 cm and an immersion time of 72 hours.

4. 4. The injection molded article of claim 1, wherein the isocyanate component comprises hexamethylene diisocyanate.

5. 5. The injection molded article of claim 1, wherein the hydroxyl-terminated intermediate component comprises poly(ethylene glycol) and the isocyanate component comprises hexamethylene diisocyanate.

6. 1. A method of making an injection molded article, comprising: preparing a thermoplastic polyurethane composition comprising a hydroxyl-terminated intermediate component that is a hydroxyl-terminated polyol, the hydroxyl-terminated intermediate component comprising poly(ethylene glycol), an isocyanate component comprising hexamethylene diisocyanate (HDI), and a chain extender component, wherein the chain extender component is 1,4-butanediol, the isocyanate component and the chain extender component constitute hard segments of the thermoplastic polyurethane, the thermoplastic polyurethane comprising 10 wt % to 50 wt % hard segments; heating the thermoplastic polyurethane composition to a temperature of 120° C. to 190° C. to melt the thermoplastic polyurethane composition; injecting the molten thermoplastic polyurethane composition into a mold; cooling the thermoplastic polyurethane composition to form an article. A method comprising:

7. The method of claim 6, wherein the thermoplastic polyurethane comprises 10 wt% to 30 wt% hard segment.

8. 8. The method of claim 6 or 7, wherein the thermoplastic polyurethane has a water absorption range of at least 70% as measured by ASTM D570 modified by using a specimen size of 6.35 cm x 0.1524 cm and an immersion time of 72 hours.

9. 9. The method of any of claims 6 to 8, wherein the thermoplastic polyurethane has a water absorption range of at least 100% as measured by ASTM D570 modified by using a specimen size of 6.35 cm x 0.1524 cm and an immersion time of 72 hours.

10. 10. The method of claim 6, wherein the hydroxyl-terminated intermediate component comprises poly(ethylene glycol).

11. The method of any of claims 6 to 10, wherein the isocyanate component comprises hexamethylene diisocyanate.

12. 1. An injection molded article comprising a thermoplastic polyurethane composition, the thermoplastic polyurethane composition comprising the reaction product of a hydroxyl-terminated intermediate component that is a hydroxyl-terminated polyol, the hydroxyl-terminated intermediate component comprising poly(ethylene glycol), an isocyanate component comprising hexamethylene diisocyanate, and a chain extender component, wherein the chain extender component is 1,4-butanediol, the isocyanate component and the chain extender component constitute hard segments of the thermoplastic polyurethane, the thermoplastic polyurethane composition comprising 10 wt % to 30 wt % hard segments, and the thermoplastic polyurethane composition has a water absorption range of at least 100% as measured by ASTM D570 modified by using specimen dimensions of 6.35 cm x 0.1524 cm and a 72 hour immersion time.

13. 1. A 3D printed article comprising a thermoplastic polyurethane composition, the thermoplastic polyurethane composition comprising the reaction product of a hydroxyl-terminated intermediate component that is a hydroxyl-terminated polyol, the hydroxyl-terminated intermediate component comprising poly(ethylene glycol), an isocyanate component comprising hexamethylene diisocyanate (HDI), and a chain extender component, where the chain extender component is 1,4-butanediol, where the isocyanate component and the chain extender component constitute hard segments of the thermoplastic polyurethane, and where the thermoplastic polyurethane comprises 10 wt % to 50 wt % hard segments.

14. 14. The 3D printed article of claim 13, wherein the thermoplastic polyurethane has a water absorption range of at least 70% as measured by ASTM D570 modified by using specimen dimensions of 6.35 cm x 0.1524 cm and an immersion time of 72 hours.

15. 15. The 3D printed article of any of claims 13-14, wherein the thermoplastic polyurethane has a water absorption range of at least 100% as measured by ASTM D570 modified by using a specimen size of 6.35 cm x 0.1524 cm and an immersion time of 72 hours.

16. 16. The 3D printed article of any of claims 13 to 15, wherein the hydroxyl-terminated intermediate component comprises poly(ethylene glycol) and the isocyanate component comprises hexamethylene diisocyanate.

17. 1. A method of making a 3D print, comprising: preparing a thermoplastic polyurethane composition comprising a hydroxyl-terminated intermediate component that is a hydroxyl-terminated polyol, the hydroxyl-terminated intermediate component comprising poly(ethylene glycol), an isocyanate component comprising hexamethylene diisocyanate (HDI), and a chain extender component, wherein the chain extender component is 1,4-butanediol, the isocyanate component and the chain extender component constitute hard segments of the thermoplastic polyurethane, the thermoplastic polyurethane comprising 10 wt % to 50 wt % hard segments; operating a system for solid freeform fabrication of an object, said system comprising a solid freeform fabrication device that deposits microscopic beads of a build material in a controlled manner; Including, The method, wherein the build material comprises the thermoplastic polyurethane composition.

18. The method of claim 17, wherein the thermoplastic polyurethane comprises 10 wt% to 30 wt% hard segment.

19. 19. The method of claim 17 or 18, wherein the thermoplastic polyurethane has a water absorption range of at least 70% as measured by ASTM D570 modified by using specimen dimensions of 6.35 cm x 0.1524 cm and an immersion time of 72 hours.

20. 20. The method of any of claims 17-19, wherein the thermoplastic polyurethane has a water absorption range of at least 100% as measured by ASTM D570 modified by using specimen dimensions of 6.35 cm x 0.1524 cm and an immersion time of 72 hours.

21. 18. The method of claim 17, wherein the hydroxyl-terminated intermediate component comprises poly(ethylene glycol).

22. 22. The method of any of claims 17 to 21, wherein the isocyanate component comprises hexamethylene diisocyanate.

23. 1. A three dimensional printed article comprising a thermoplastic polyurethane composition, the thermoplastic polyurethane composition comprising the reaction product of a hydroxyl-terminated intermediate component that is a hydroxyl-terminated polyol, the hydroxyl-terminated intermediate component comprising poly(ethylene glycol), an isocyanate component comprising hexamethylene diisocyanate, and a chain extender component, wherein the chain extender component is 1,4-butanediol, the isocyanate component and the chain extender component constitute hard segments of the thermoplastic polyurethane, the thermoplastic polyurethane composition comprising 10 wt % to 30 wt % hard segments, and the thermoplastic polyurethane composition has a water absorption range of at least 100% as measured by ASTM D570 modified by using a specimen size of 6.35 cm by 0.1524 cm and a 72 hour immersion time.

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