Patent Description:
A polyurethane is a family of polymeric materials whose chains have soft and hard segments. Because of this unique structure, polyurethane materials have many excellent properties, for example, resistance to low temperature, abrasion resistance, and high stability in biological environment, thus widely used in airspace products, medical devices, coatings, textile and leather.

Polyurethanes can be tailored to produce a range of products from soft and flexible to hard and rigid. They can be extruded, injection molded, compression molded, and solution spun, for example. Thus, polyurethanes are important biomedical polymers, and are used in implantable devices such as artificial hearts, cardiovascular catheters, pacemaker lead insulation, etc..

Commercially available polyurethanes used for implantable applications include BIOSPAN segmented polyurethanes available from Polymer Technology Group of Berkeley, Calif, PELLETHANE segmented polyurethanes available from Dow Chemical, Midland, Mich. , and TECOFLEX segmented polyurethanes available from Thermedics, Inc. , Woburn, Mass. These polyurethanes and others are described in the article "<NPL>). Typically, polyether polyurethanes exhibit more biostability than polyester polyurethanes, and are therefore generally preferred polymers for use in biological applications,.

<CIT> describes polyisobutylene-based polyurethanes.

<CIT> describes the use of polydiene diols in thermoplastic polyurethanes.

Polyether polyurethane elastomers, such as PELLETHANE <NUM>-80A (P80A) and <NUM>-55D (P55D), which are believed to be prepared from polytetramethylene ether glycol (PTMEG) and <NUM>,<NUM>'-diphenylmethane diisocyanate (MDI) extended with <NUM>,<NUM>-butanediol (BDO), are widely used for implantable cardiac pacing leads. Pacing leads are insulated wires with electrodes that carry stimuli to tissues and biologic signals back to implanted pulse generators. The use of polyether polyurethane elastomers as insulation on such leads has provided significant advantage over silicone rubber, primarily because of the higher tensile strength and elastic modulus of the polyurethanes.

Currently, polyurethane materials used in medical devices often have the following structures: the soft segments are formed by oligomer polyols such as polytetramethyleneoxide (PTMO), polydimethylsiloxane (PDMS), or aliphatic polycarbonate, while the hard segments are formed by diisocyanate such as <NUM>,<NUM>'-diphenylmethane diisocyanate (MDI) or hydrogenated MDI (HMDI), and chain extender such as <NUM>,<NUM>-butanediol (BDO). However, during long term use, polyether or polycarbonate polyurethanes may chemically degrade through oxidation, hydrolysis, or enzymatic reactions which could result in material failure, or, under certain conditions, even device failure. For example, polyether polyurethane materials, when used in long term implants, can be oxidized. The oxidation caused by the inflammatory reactions often occurs at the device surface contacting the tissues. It is known as environmental stress cracking. The oxidation reaction that occurs at the device surface contacting certain metallic surface (e.g. cobalt and its alloys) is known as metal ion induced oxidization.

Generally, ether bonds are susceptible to oxidation degradation. Unfortunately, oxidative chemicals are present in the patients' biology. Therefore, the key for solving such a problem is to develop a polyurethane material which is composed of soft segments that are more resistant to oxidation reactions than polyether. A number of polyurethanes with new soft segments have been developed in the past, for example, polycarbonate polyurethane (Carbothane™ by Lubrizol, Bionate™ by DSM, etc.), PDMS polyurethane (ElastEon™ by Biomerics, Pursil™ by DSM, etc.), etc. Those new materials have demonstrated improved resistance to oxidation degradation. However, there are concerns of hydrolysis degradation with them.

Recently, a polyurethane material which is made of polyisobutylene soft segment has shown excellent oxidation and hydrolytic degradation resistance. However, the synthesis of this material requires complicated processes. Production of the material at commercial scale with comparable cost remains an issue. Polyethylene diol has been proposed in the past (<CIT>). It was assumed that polyurethane made of polyethylene segments would have good resistance to oxidation and hydrolytic reactions. Similar to polyisobutylene polyurethane, synthesis process of polyethylene polyurethane remains a technical challenge, which continues to delay the commercialization of the material.

Therefore, there still is a need to develop an effective method for producing polyolefin diols to make polyurethane materials, so as to provide the identification of materials, particularly polyurethanes, that have the desired stability to oxidation and hydrolysis, and desirable physical properties, as well as good processability, particularly for use in implantable medical devices.

The present disclosure is an effective method for preparing polyolefin polyurethane. The method consists of two parts. The first part is making polyolefin diols by polymerizing dienes followed by hydrogenation. A second part is making polyurethane materials by using microwave heating. The polyolefin polyurethane made in the present way is expected to have the excellent properties for long term biomedical implant applications.

Aspects, embodiments and examples of the present disclosure in which the thermoplastic elastomer is not obtained using microwave radiation do not form part of the invention and are merely provided for illustrative purposes. For example, the second aspect and example <NUM> of this disclosure fall under the scope of claim <NUM>.

The present application provides a production method that provides a feasible path to make saturated polyethylene diol and other polyolefin diols. It is simple and highly efficient. Specifically, it can be realized with lower equipment cost, shorter reaction time, higher yield, fewer byproducts, and lower energy consumption than that with traditional methods. It is suitable for continuous production at large scale.

Products made with this method can be used for medical devices, particularly for implantable medical devices such as a medical device electrical lead.

The present application designs and makes cardiac electrical therapy delivery leads with the polyethylene and branched polyethylene polyurethane materials via hydrogenation followed by microwave polymerization methods. The leads resist to oxidation degradation failure and have same mechanical performance as the leads made of polyether polyurethane.

In the present application, the terms are defined as follows:
Polymerization is a chemical reaction between many monomers of one or more types. The reaction results in formation of a long chain molecule. The reactive groups of the monomers are chemically linked together and become different groups. For example, a hydroxyl of one monomer and an isocyanate of another monomer can react and form a urethane group. The urethane groups present in the polymer chain and function as linkages.

Diol is an organic compound that has two hydroxyl groups that can react with isocyanate groups of other compounds.

Diisocyanate is an organic compound that has two isocyanate groups that can react with hydroxyl groups to form urethane groups.

Chain extender is a compound that has a molecular weight of less than 200D and two hydroxyl groups that can react with isocyanates. Chain extender can also be diamine or compound with amine at one end and hydroxyl group at the other end, such as <NUM>-amino-<NUM>-butanol.

Catalyst is a compound that can accelerate reactions, but is not a part of reaction products.

Unsaturated soft segment diol is a soft segment diol containing C=C double bonds or other unsaturated hydrocarbon bonds.

Hydrogenation is a reaction to convert unsaturated hydrocarbon groups into saturated groups by adding hydrogen atoms, for example converting C=C into C-C. The reaction usually needs hydrogen gas and catalysts.

Polyurethane prepolymer is a polymer that has a molecular weight of 50D to <NUM>,000D and has two isocyanate groups at the ends of each molecule that can react with chain extender to form urethane groups.

Polyurethane is a polymer that is formed through reactions between diol and diisocyanate compounds. Urethane groups formed are the linkages between the monomers.

Chain branch is a chemical group chemically linked to the main chain structure as a side group. A polymer chain can have one or more than one chain branch. Chain braches can be same or different. Some chain branch examples as methyl, ethyl, propyl, butyl, isobutyl, etc..

Microwave radiation reactor is a chemical reactor in which the reaction can proceed under microwave radiation. A typical microwave radiation reactor has noncontact infrared temperature sensors that can be used to monitor reaction mixture temperature and allow the temperature to be controlled on real-time base.

A "biomaterial" may be defined as a material that is substantially insoluble in body fluids and tissues and that is designed and constructed to be placed in or onto the body or to contact fluid or tissue of the body. Ideally, a biomaterial will not induce undesirable reactions in the body such as blood clotting, tissue death, tumor formation, allergic reaction, foreign body reaction (rejection) or inflammatory reaction; will have the physical properties such as strength, elasticity, permeability and flexibility required to function for the intended purpose; can be purified, fabricated and sterilized easily; and will substantially maintain its physical properties and function during the time that it remains implanted in or in contact with the body.

An "elastomer" is a polymer that is typically capable of being stretched to approximately twice its original length and retracting to approximately its original length upon release.

A "medical device" may be defined as a device that has surfaces that contact blood or other bodily fluids in the course of their operation, which fluids are subsequently used in patients. This can include, for example, extracorporeal devices for use in surgery such as blood oxygenators, blood pumps, blood sensors, tubing used to carry blood and the like which contact blood which is then returned to the patient. This can also include endoprostheses implanted in blood contact in a human or animal body such as vascular grafts, stents, stent grafts, medical electrical leads, indwelling catheters, heart valves, and the like, that are implanted in blood vessels or in the heart. This can also include devices for temporary intravascular use such as catheters, guide wires, balloons, and the like which are placed into the blood vessels or the heart for purposes of monitoring or repair.

In one embodiment, the polyurethane cited above can be made in the following way in two steps.

In the first step, making a diol having the following structure:
<CHM>
wherein n is an integer of <NUM>-<NUM>; R<NUM> and R<NUM> are independently H, C<NUM>-<NUM> alkyl, C<NUM>-<NUM> cycloalkyl or C<NUM>-<NUM> alkenyl.

In order to achieve the structure in the first step, a proper diene monomer or a group of proper diene monomers are selected. The diene monomers polymerize alone or copolymerize with other alkene monomers using hydrogen peroxide as catalyst for both cases. The dienes include, but not limited to, butadiene, isoprene, etc. The alkene monomers include, but not limited to, ethylene, propylene, butylene, isobutylene and combination thereof. The molecular weight of polydiene can be controlled by adjusting the ratio of the total double bonds and hydrogen peroxide. The polydienes can also be made by anionic polymerization, living free radical polymerization, and/or other polymerization reactions followed by terminating the two chain ends with hydroxyl groups to form diol structures.

In the second step, the structure (I) made in the first step is hydrogenated into the following saturated diols (II):
<CHM>
wherein n is an integer of <NUM>-<NUM>; R<NUM> and R<NUM> are independently H, C<NUM>-<NUM> alkyl, or C<NUM>-<NUM> cycloalkyl.

The diols according to the structure (II) is hydrogenated polyethylene diol, hydrogenated polypropylene diol, hydrogenated polybutylene diol, hydrogenated polybutadiene diol, hydrogenated polypentylene diol, hydrogenated poly(<NUM>-methyl-<NUM>-pentene) diol, hydrogenated polyhexene diol, hydrogenated poly(ethylene-propylene) copolymer diol, or hydrogenated polyisobutylene diol.

During preparing a polyurethane, water and /or other impurities are removed before conducting hydrogenation to avoid poisoning the hydrogenation catalysts. An expert in the field should know methods of removing impurities. One method can be heating the mixtures while applying vacuum for proper duration.

In the first aspect, the present invention provides a medical device comprising a biomaterial formed from a polyurethane, polyurea, or polyurethane-urea elastomer being made of a soft segment diols or diamines including, but not limited to, saturated hydrogenated polyolefin diols, hydrogenated polyolefin diamines, or a mixture of hydrogenated polyolefin diols, hydrogenated polyolefin diamines, polyether diols, and/or polycarbonate diols. The polyolefin diols or polyolefin diamine that may have <NUM> to <NUM> carbon atoms in the main chain, wherein each carbon atom in the main chain may have <NUM> to <NUM> side chains and each side chain can have <NUM> to <NUM> carbon atoms.

In this invention, the number-average molecular weight of the elastomer is <NUM>× <NUM><NUM>-<NUM>,<NUM>× <NUM><NUM> g/mol, preferably <NUM>× <NUM><NUM>-<NUM> × <NUM><NUM> g/mol; the ultimate elongation of the elastomer is <NUM>-<NUM>%; the Young's modulus of the elastomer is <NUM> to <NUM>,000MPa; and the ultimate tensile strength of the elastomer is <NUM>-100MPa.

In this invention, the medical device may have the following structure, comprising:.

In this invention, the metal wire may include, but not limited to: MP35N, Ag cored MP35N, Ta, and low Ti MP35N; and, the polymeric insulation material may include, but not limited to: fluoropolymer, silicone and polyimide.

In this invention, the medical device is an electrical stimulation device, including but not limited to: neurological stimulation device, cardiac stimulation device, heart assist device, gastrointestinal stimulation device, skeletomuscular stimulation devices, sensing devices, etc..

In this invention, the medical device is an implantable cardia pacing lead, including but not limited to: coaxial lead, multilumen lead, etc..

In this invention, the medical device is an implantable cardioverter defibrillation lead, including but not limited to: coaxial lead, multilumen lead, etc..

In this invention, the medical device is a sensing device, including but not limited to: electrical sensing, mechanical sensing, chemical sensing, etc..

In this invention, the medical device is a combined stimulation lead with sensors.

In this invention, the elastomer is an insulation layer.

In this invention, the elastomer is an outside sheath.

In this invention, the elastomer is a structural component.

In this invention, the elastomer is a spatial filling component.

In this invention, the elastomer is a component for jointing other components.

In this invention, the medical device is an implantable cardioverter defibrillation lead, wherein.

In this invention, the medical device is an implantable cardiac pacing lead, wherein.

In this invention, the medical device is is an implantable cardioverter defibrillation lead, wherein.

In the second aspect, the present invention provides a method for preparing a medical device, comprising:.

In this invention, in step (i), adding diols and a solvent into a reactor, for example, a hydrogenating reactor; after diol is dissolved, adding a noble metal hydrogenating catalyst and hydrogen gas into the reactor; controlling the temperature and pressure to be within pre-planned ranges and letting the reaction continue until completion; and, separating the hydrogenating diols, purifying, and drying them.

In this invention, in step (i), the volume of the hydrogenating reactor is <NUM>-<NUM>, the reaction temperature is <NUM>-<NUM>, preferably <NUM>-<NUM>, the reaction pressure is <NUM>-100MPa, and the reaction time is <NUM>-<NUM>; and, the noble metal hydrogenating catalyst is one of the Pt group metals (i.e. Ru, Rh, Pd, Os, Ir and Pt) carrier catalysts.

In this invention, in step (ii), before conducting pre-polymerization, heating and dehydrating the hydrogenated soft segment obtained in step (i) in vacuum, wherein the temperature of heating and dehydrating is <NUM>-<NUM>, and the time of heating and dehydrating is <NUM>-<NUM>.

In this invention, in step (ii), the diisocyanate is selected from toluene-<NUM>,<NUM>-diisocyanate (TDI), its isomer or a mixture thereof; <NUM>,<NUM>'-diphenylmethane diisocyanate (MDI), hexamethylene diisocyanate, isophorone diisocyanate, methylene bis(cyclohexyl) diisocyante (HMDI), trans-cyclohexane,<NUM>,<NUM>-diisocyante (CHDI), p-phenyl diisocyanate, lysine diisocyanate, p-phenyl dimethylene diisocyanate, <NUM>,<NUM>-cyclopentane diisocyanate, p-tetramethyl ditoluene diisocyanate, m-tetramethyl ditoluene diisocyanate, and mixtures thereof.

In this invention, in step (ii), the polymerization catalyst is selected from the group consisting of triethylene diamine, dibutyldilaurate tin, stannous octoate, and mixtures thereof.

In this invention, in step (ii), the pre-polymerization temperature is <NUM>-<NUM>, preferably from <NUM> to <NUM>, and the pre-polymerization time is <NUM>-<NUM>.

In this invention, in step (ii), the microwave radiation power is <NUM>-800W for <NUM> to <NUM> of reactant mixture.

In this invention, in step (iii), the chain extender is selected from ethylene glycol, <NUM>,<NUM>-propylenediol, <NUM>,<NUM>-butanediol, <NUM>,<NUM>-hexandiol, <NUM>,<NUM>-cyclohexanediol, <NUM>,<NUM>-henxanediol, <NUM>,<NUM>-octanediol, <NUM>,<NUM>-nondadiol, <NUM>,<NUM>-decanediol, p-diphenyl ethylene diol, colophony dimethol, ethylenediamine, propylenediamine, butylenediamine, hexanediamine, cyclohexanediamine, and mixture thereof;.

In this invention, in step (iii), the polymerization temperature is <NUM>-<NUM>, and the polymerization time is <NUM>-<NUM>, preferably <NUM>-<NUM>.

In this invention, the steps (i)-(iii) are conducted in the presence of a solvent, wherein the solvent is selected from the group consisting of toluene, xylene, tetrahydrofuran, trichloromethane, N,N-dimethyl formamid, ethyl acetate, N,N-dimethylacetamide, dimethyl sulfoxide and mixtures thereof.

In this invention, the method comprises:.

In the third aspect, the present invention provides a medical device electrical lead, comprising:.

In the fourth aspect, the present invention provides a method of using a medical device electrical lead, the method comprising:.

In the fifth aspect, the present invention provides use of the medical device for correcting cardiac rhythm, defibrillating, assisting hearts, sensing, stimulating neurological systems, gastrointestinal system, skeletomuscular tissues or organs, etc..

With reference to <FIG>, it shows two designs of lead body according to the embodiments of the present application. The cable design is generalized as the reference sign <NUM>, which comprises: cable of metal wires <NUM> at the core; a layer of polymeric insulation materials <NUM> surrounding the cable of metal wires <NUM>; another layer of polymeric insulation materials <NUM> surrounding the layer of polymeric insulation materials <NUM>; coil of metal wires <NUM> surrounding the layer of polymeric insulation materials <NUM>; and a layer of the biomaterial <NUM> surrounding the coil of metal wires <NUM>. The coin design is generalized as the reference sign <NUM>, which comprises: coil of metal wires <NUM> at the core; a layer of polymeric insulation materials <NUM> surrounding the coil of metal wires <NUM>; another layer of polymeric insulation materials <NUM> surrounding the layer of polymeric insulation materials <NUM>; coil of metal wires <NUM> surrounding the layer of polymeric insulation materials <NUM>; and a layer of the biomaterial <NUM> surrounding the coil of metal wires <NUM>. This tubing may have OD of <NUM>-<NUM>, nominal <NUM>; wall thickness of <NUM>-<NUM>, nominal <NUM>; and material rigidity (Shore Durometer) of 50A-75D, preferably 80A-55D, nominal 55D. This tubing can be made with extrusion process.

With reference to <FIG>, it shows another design of lead body according to the embodiment of the present application, comprising: a multi-lumen tubing <NUM> having a plurality of conductor lumens each containing a plurality of coil of metal wires <NUM> and cable of metal wires <NUM>, wherein the multi-lumen tubing <NUM> is made from the biomaterial; and layers of polymeric insulation materials <NUM> surrounding the coil of metal wires <NUM> and cable of metal wires <NUM>.

With reference to <FIG>, it shows another design of lead body according to the embodiment of the present application, comprising: a multi-lumen tubing <NUM> having a plurality of conductor lumens each containing a plurality of coil of metal wires <NUM> and cable of metal wires <NUM>, wherein the multi-lumen tubing <NUM> is made from the biomaterial; an overlay tubing <NUM> surrounding the multi-lumen tubing <NUM>; and layers of polymeric insulation materials <NUM> surrounding the coil of metal wires <NUM> and cable of metal wires <NUM>.

With reference to <FIG>, it is a plan view of the medical device electrical lead according to the embodiment of the present application. As shown in <FIG>, the pacing lead <NUM> includes a connector assembly at its proximal end, including a first conductive surface <NUM>, a second conductive surface <NUM>, and two insulative segments <NUM> and <NUM>; insulative segments <NUM> and <NUM> are each provided with a plurality of sealing rings <NUM>; extending from the connector assembly is an elongated lead body, including an outer insulative sheath <NUM>, which is formed from the polymers described above; within insulative sheath <NUM> is located an elongated conductor (not shown), such as a quadrifilar, multiconductor coil, which is described in <CIT>); two of the conductors within the coil are coupled to conductive surface <NUM>, and the other two are coupled to conductive surface <NUM>; at the distal end of the lead are located a ring electrode <NUM>, coupled to two of the conductors, and a tip electrode <NUM>, coupled to the other two of the four conductors of the quadrifilar coil; and, extending between ring electrode <NUM> and tip electrode <NUM> is an additional insulative sheath <NUM>. Such medical electrical leads can be implanted into a vein or artery of a mammal and electrically connected to an implantable medical device.

The invention has been described with reference to various specific and preferred embodiments and will be further described by reference to the following detailed Examples. It is understood, however, that there are many extensions, variations, and modification on the basic theme of the present invention beyond that shown in the examples and detailed description, which are within the scope of the present invention.

Examples are given below in order to specifically describe the present invention; however, the present invention is not limited to the examples that are described below. In the following examples, measurements or quantity ratios are based on weight in all instances.

<NUM> of polybutadiene diol and <NUM> THF were added into a hydrogenating kettle; after polybutadiene diol was dissolved, <NUM> of Pt hydrogenating catalyst and hydrogen gas were added into the hydrogenating kettle; the temperature was controlled to be <NUM> and pressure was controlled to be 2MPa and the reaction continued for <NUM> hours until completion; and, the obtained hydrogenated diols were separated, purified, and dried.

<NUM> toluene and <NUM> hydrogenated polybutadiene diol (H-HTPB) were added in a <NUM> glass reactor. The mixture was stirred until the H-HTPB was dissolved in the toluene. Then <NUM> <NUM>,<NUM>'-diphenyl methane diisocyanate was added followed by adding 40µL dibutyldilaurate tin catalyst. Microwave radiation (400W) was then used to heat the reaction mixture to maintain its temperature at <NUM> while it was stirred. After <NUM> hours of reaction, <NUM> of chain extender BDO (calculated according to the amount of titrated isocyanate such that the total molar of OH is equal to that of isocyanate); and then the temperature was raised to <NUM> by increasing microwave power to 500W. Let the reaction continue for <NUM> more hours. When the isocyanate completely reacted based on FI-IR test, the reaction was stopped. The reaction solution was poured into menthol to precipitate the polymer product. The mixture was placed in a refrigerator for <NUM> hours. The solid polymer product was harvested by centrifuging mixture. The product was dried in vacuum oven for <NUM> hours.

The yield of the reaction was <NUM>%. The number-average and weight-average molecular weights measured with Gel Permeation Chromatography (GPC) were Mn= <NUM>×<NUM><NUM> g/mol, and Mw=<NUM>×<NUM><NUM> g/mol.

<FIG> shows UV absorbance spectrum of polybutylene glycol before hydrogenating vs. after hydrogenating. The characteristic absorbance peak of double bond of HTPB at <NUM> disappeared after hydrogenating, indicating that all of the double bond in HTPB were hydrogenated.

<FIG> shows IR spectrum of the resulting polyurethane. The characteristic peak of isocyanate group -NCO at <NUM>,<NUM>-<NUM> disappeared, indicating that all of the residual isocyanate groups had been reacted in the last step. The peaks at <NUM>,<NUM>-<NUM> and <NUM>,<NUM>-<NUM> were assigned to -NH- of the urethane group and the peak at <NUM>,<NUM>-<NUM> was assigned to -C=O of urethane group. These two peaks suggest the formation of urethane.

<NUM> toluene was added in a <NUM> glass reactor and heated to <NUM>. <NUM> hydrogenated polybutadiene diol (H-HTPB) was added in the reactor. The mixture was stirred until the H-HTPB was dissolved in the toluene. Then <NUM> <NUM>,<NUM>'-diphenyl methane diisocyanate was added followed by adding 40µL dibutyldilaurate tin catalyst. The reaction mixture was heated with a regular heater to maintain its temperature at <NUM> while it was stirred. After <NUM> hours of reaction, <NUM> of chain extender BDO (calculated according to the amount of titrated isocyanate such that the total molar of OH is equal to that of isocyanate); and then the temperature was raised to <NUM> by increasing heating power. Let the reaction continue for <NUM> more hours. When the isocyanate completely reacted based on FI-IR test, the reaction was stopped. The reaction solution was poured into menthol to precipitate the polymer product. The mixture was placed in a refrigerator for <NUM> hours. The solid polymer product was harvested by centrifuging mixture. The product was dried in vacuum oven for <NUM> hours.

The yield of the reaction was <NUM>%, and the number-average and weight-average molecular weights measured by Gel Permeation Chromatography (GPC) were Mn = <NUM>×<NUM><NUM> g/mol, and Mw= <NUM>×<NUM><NUM> g/mol.

The mechanical properties of polyurethane include follows:.

Claim 1:
A medical device comprising a thermoplastic elastomer that is composed of soft segments and hard segments, wherein
the soft segments are made of saturated polyolefin diols or polyolefin diamine that has up to <NUM> carbon atoms in the main chain, wherein each carbon atom in the main chain has <NUM> to <NUM> side chains and each side chain has <NUM> to <NUM> carbon atoms,
the hard segment is made of a diisocyanate and a chain extender,
the hard segments make up <NUM>-<NUM>% of the elastomer and the soft segments make up the rest,
the number-average molecular weight of the elastomer is <NUM>×<NUM><NUM>-<NUM>×<NUM><NUM> g/mol; the ultimate elongation of the elastomer is <NUM>-<NUM>%; the Young's modulus of the elastomer is <NUM> to <NUM>,000MPa; and the ultimate tensile strength of the elastomer is <NUM>-100MPa, and
characterized in that the thermoplastic elastomer is obtained from a mixture including the saturated polyolefin diol or polyolefin diamine, the diisocyanate and the chain extender by using microwave radiation.