HK1078098B - Copolymers of tetrahydrofuran, ethylene oxide and an additional cyclic ether - Google Patents

Description

Copolymers of tetrahydrofuran, ethylene oxide and other cyclic ethers

Technical Field

The present invention relates to novel compositions comprising copolymers of tetrahydrofuran, ethylene oxide and other cyclic ethers.

Background

Homopolymers of tetrahydrofuran (THF, oxolane), namely polytetramethylene ether glycol, are well known for use as soft segments in polyurethanes. These homopolymers provide superior dynamic properties to polyurethane elastomers and fibers. They have very low glass transition temperatures, but their crystalline melting temperatures are above room temperature. Therefore, they are waxy solids at ambient temperatures and need to be maintained at elevated temperatures to prevent curing.

Copolymerization with cyclic ethers has been used to reduce the crystallinity of polytetramethylene ether chains. This lowers the polymer melting temperature of the polyglycol and at the same time can improve certain dynamic properties of polyurethanes comprising such copolymers as soft segments. Among the comonomers used for this purpose ethylene oxide is present, which, depending on the comonomer content, can lower the copolymer melting temperature below ambient temperature. The use of copolymers of THF and ethylene oxide can also improve certain dynamic properties of the polyurethane, such as elongation at break, which is desirable for certain end-use applications.

Copolymers of THF and ethylene oxide are well known in the art. Their preparation is described, for example, by Pruckmayr in U.S. Pat. No. 4,139,567 and U.S. Pat. No. 4,153,786. Such copolymers may be prepared by any known cyclic ether polymerization method, for example as described in "polytetrahydrofuran" by p. Such polymerization methods include catalysis with strong proton or Lewis acids, catalysis with heteropolyacids, and catalysis with perfluorosulfonic acids or acidic resins. In some cases, it may be advantageous to use a polymerization accelerator, such as a carboxylic acid anhydride, as described in U.S. Pat. No. 4,163,115. In these cases, the initial polymer product is a diester, which needs to be hydrolyzed in a subsequent step to produce the desired polymer diol.

U.S. patent 5,684,179 to Dorai discloses the preparation of diesters of polytetramethylene ethers from the polymerization of THF with one or more comonomers. While Dorai includes 3-methyltetrahydrofuran, ethylene oxide, propylene oxide, and the like, it does not describe glycol copolymers of tetrahydrofuran, ethylene oxide, and cyclic or substituted cyclic ethers.

Diols formed as copolymers of tetrahydrofuran and ethylene oxide provide advantages over homopolymer diols in terms of physical properties. At ethylene oxide contents above 20 mole percent, the copolymer diol is a moderately viscous liquid at room temperature and has a lower viscosity at temperatures above the melting point of polytetrahydrofuran compared to polytetrahydrofuran of the same molecular weight. Certain physical properties of polyurethanes prepared from tetrahydrofuran copolymers are superior to those of polyurethanes prepared from tetrahydrofuran homopolymers.

However, there are certain disadvantages associated with the use of Ethylene Oxide (EO) in these copolymers. EO is quite hydrophilic and may increase the water sensitivity of the corresponding polyurethane when used in the required concentrations.

Disclosure of Invention

The present invention is a copolymer diol prepared by polymerizing tetrahydrofuran, ethylene oxide, and at least one other cyclic ether. The present invention also relates to polyurethane polymers comprising the reaction product of at least one organic polyisocyanate compound and a copolymer diol prepared by the copolymerization of tetrahydrofuran, ethylene oxide and at least one other cyclic ether. The invention also relates to spandex filaments comprising the polyurethane described above.

Detailed Description

The present invention relates to a material of glycol composition comprising a copolymer of tetrahydrofuran, ethylene oxide and one or more other cyclic ethers. Herein, the term "copolymer" refers to a polymer formed from at least three monomers. Since the addition of ethylene oxide to polymeric diols will increase the hydrophilic character of subsequent polyurethane products, it is desirable to control or even minimize this hydrophilicity and thereby reduce the water sensitivity of the products ultimately made from these copolymers. Other cyclic ethers or substituted cyclic ethers are more hydrophobic and therefore can compensate for the increased hydrophilicity caused by the ethylene oxide comonomer. This serves to reduce the water sensitivity of compounds such as polyurethanes made from the copolymers of the present invention. Examples of such hydrophobic monomers are alkyl substituted tetrahydrofurans and larger cyclic ethers containing a smaller proportion of oxygen in the molecule than ethylene oxide. Copolymer diols can be produced that contain tetrahydrofuran and ethylene oxide units in the polymer chain as well as other polyether monomers distributed in a random manner along the polymer backbone. It should be noted that in this case the alkyl substituted oxolane, e.g. 3-methyloxolane, is referred to as the corresponding alkyl substituted tetrahydrofuran, i.e. 3-methyltetrahydrofuran. Herein, the term "cyclic ether" is understood to include both unsubstituted and substituted forms.

The copolymers of the present invention can be produced by the method of Pruckmayr in U.S. patent 4,139,567 using a solid perfluorosulfonic acid resin catalyst. Alternatively, any other acidic cyclic ether polymerization catalyst may be used to produce these copolymers, such as heteropolyacids. Heteropolyacids and salts thereof useful in the practice of the present invention are catalysts for the polymerization and copolymerization of cyclic ethers as described by Aoshima et al in U.S. Pat. No. 4,658,065.

A wide variety of strong acid and excessively acidic catalysts well known to those skilled in the art can be used for the copolymerization of the cyclic ethers of the present invention. These include, but are not limited to, fluorinated sulfonic acids, supported Lewis or Bronsted acids, as well as various zeolite and heterogeneous acid catalysts. Perfluorinated ion exchange polymers (PFIEPs), such as NAFION ® PFIEP products, a range of perfluorinated sulfonic acid polymers, are generally suitable for use at EO levels of about 25 mole% or greater. NAFION ® is available from e.i. du Pont DE Nemours and Company, Wilmington, DE (hereinafter DuPont). Fluorosulfonic acids are widely used as catalysts, especially for lower levels of EO. Heteropolyacids, (e.g. phosphotungstic acid) are generally suitable in the range of EO levels used.

The molar concentration of ethylene oxide in the polymer is from 1% to 60%, and preferably from 1% to 30%. The molar concentration of the other cyclic ethers is from 1% to 40% and preferably from 1% to 20%.

The cyclic ether may be represented by formula 1:

wherein the content of the first and second substances,

r is a C1 to C5 alkyl or substituted alkyl group,

n is an integer from 3 to 4 or from 6 to 9,

m is zero or 1. Except that when n is 4, m is 1.

Examples of cyclic ethers are as follows:

chemical name of Ring C

C3 oxetane, methyl-oxetane and dimethyl-oxetane,

c4 alkyl-tetrahydrofurans such as 3-methyl-tetrahydrofurane and 3-ethyl-tetrahydrofurane,

and 2-methyl-tetrahydrofuran, and a pharmaceutically acceptable salt thereof,

the oxacycloheptane of C6 is,

the alcohol is C7 oxygen-heterocyclic octane,

c8 Oxononane, and

c9 Oxocyclodecane

Although not represented by the above formula, 3, 4-dimethylcyclopentane (3, 4-dimethyl-tetrahydrofuran) and perfluoroalkyl oxiranes, such as (1H, 1H-perfluoropentyl) -oxiranes, may be used for purposes of the present invention as other cyclic substituted ethers.

The molar percentage ratio of monomers in the THF/EO/3-MeTHF copolymer is 3-50% EO, 5-25% 3-MeTHF and the balance THF. The preferred ranges of mole percentages are 8-25% EO, 5-15% 3-MeTHF and the balance THF.

In the copolymerization process of the present invention, ethylene oxide functions as a polymerization initiator (or accelerator), and copolymerization rapidly initiates ring opening of the other cyclic ethers of the present invention starting from the opening of the strained 3-membered ring. Due to the combination of the ethylene oxide, tetrahydrofuran and a third monomer, such as alkyl substituted tetrahydrofuran, with hydrophobic and hydrophilic comonomer units, careful design of the composition provides novel polymer chains. These novel copolymers are valuable as "soft segments" in polyurethane polymers. They are particularly valuable when used to make spandex.

"Spandex" refers to a manufactured fiber in which the fiber-forming substance is a long-chain synthetic polymer composed of at least 85% by weight of a segmented polyurethane. The multi-block polyurethane can be made from a polymeric diol, a diisocyanate, and a difunctional chain extender. In the preparation of spandex polymers, the polymer is chain extended by sequential reaction of hydroxyl end groups with diisocyanates and diamines. In each case, the copolymer must be chain extended to provide a spinnable polymer with the necessary properties, including viscosity.

The polymeric diols useful in making the polyurethanes of the present invention may have a number average molecular weight of about 1500-. Diisocyanates which may be used include 1-isocyanato-4- [ (4-isocyanatophenyl) methyl ] benzene, ("4, 4 '-MDI") 1-isocyanato-2- [ (4-isocyanatophenyl) methyl ] benzene ("2, 4' -MDI"), mixtures of 4, 4 '-MDI and 2, 4' -MDI, bis (4-isocyanatocyclohexyl) methane, 5-isocyanato-1- (isocyanatomethyl) -1, 3, 3-trimethylcyclohexane, 1, 3-diisocyanato-4-methyl-benzene, and mixtures thereof. When a polyurethane is desired, the chain extender is a diol, such as ethylene glycol, 1, 3-propanediol, or 1, 4-butanediol, and mixtures thereof.

Optionally, monofunctional alcohol chain terminators such as butanol may be used to control polymer molecular weight, and higher functional alcohol "chain branching agents" such as pentaerythritol may be used to control viscosity. Such polyurethanes can be melt spun, dry spun or wet spun into spandex. When a polyurethaneurea (a subset of polyurethanes) is desired, the chain extender is a diamine, such as ethylenediamine, 1, 3-butanediamine, 1, 4-butanediamine, 1, 3-diamino-2, 2-dimethylbutane, 1, 6-hexanediamine, 1, 2-propanediamine, 1, 3-propanediamine, N-methylaminobis (3-propylamine), 2-methyl-1, 5-pentanediamine, 1, 5-diaminopentane, 1, 4-cyclohexanediamine, 1, 3-diamino-4-methylcyclohexane, 1, 3-cyclohexanediamine, 1-methylenebis (4, 4' -diaminohexane), 3-aminomethyl-3, 5, 5-trimethylcyclohexane, 1, 3-diaminopentane, 1-diaminopentane, or mixtures thereof, M-xylylenediamine and mixtures thereof. Optionally, chain terminators, such as diethylamine, cyclohexylamine or n-hexylamine, can be used to control the molecular weight of the polymer, and trifunctional "chain branching agents" such as diethylenetriamine can be used to control solution viscosity. When spandex is desired, the polyurethaneurea is typically dry spun or wet spun.

The practice of the present invention is illustrated by the following examples, which are not intended to limit the scope of the invention.

Material

Tetrahydrofuran, 2-methyl-tetrahydrofuran, fluorosulfonic acid, and phosphotungstic acid hydrate are available from Aldrich Chemical, Milwaukee WI. Phosphotungstic acid hydrate is dehydrated by heating at 300 ℃ for at least three hours before use.

3-methyl-tetrahydrofuran, 3-ethyl-tetrahydrofuran and oxepane were prepared according to the methods described in the literature.

Examples

Example 1

This example serves to illustrate the copolymerization of tetrahydrofuran, 3-ethyl-tetrahydrofuran and ethylene oxide. Tetrahydrofuran (160g, 2.22 moles) and 3-ethyl-tetrahydrofuran (40g, 0.4 moles) were charged to a 500 ml 4-neck round bottom flask equipped with a mechanical stirrer, dry ice condenser, thermometer and gas inlet tube. 1, 4-butanediol (0.8g, 0.01 mole) was added as a molecular weight control agent along with 10 grams of dry, cryoground NAFION ® NR-50 to less than 80 mesh. NAFION ® NR-50 is a solid perfluorosulfonic acid resin in bead form, available from DuPont. The polymerization mixture was stirred and heated to 50 ℃. At this point ethylene oxide was added slowly through the gas inlet tube and continued until 8.3g (0.19 moles) had been added, which took about 4 hours. The EO feed was then cut off and the gas inlet system was flushed with dry nitrogen. Heating was continued for an additional 15 minutes, after which the polymerization vessel was cooled to 30 ℃ and then filtered. The solid catalyst is recovered and can be reused. The polymer solution was dried under vacuum at 100 ℃ under a pressure of 0.2mmHg (0.027 kPa). The final product filtration gave 50g (24%) of a clear, sticky polymer, which was characterized by Fourier transform Infrared Spectroscopy (FTIR), Nuclear magnetic resonance Spectroscopy (NMR) and Gel Permeation Chromatography (GPC). It has the following properties and composition:

number average molecular weight: 3100

Tetrahydrofuran content: 72 mol%

Ethylene oxide content: 25 mol% of

3-ethyl-tetrahydrofuran content: 3 mol% of

Example 2

This example serves to illustrate the copolymerization of tetrahydrofuran, 3-ethyl-tetrahydrofuran and ethylene oxide.

A 250 ml round bottom polymerization reactor was equipped with a mechanical stirrer, a dry ice reflux condenser with a desiccated gypsum moisture barrier, a thermometer, and a gas inlet tube. Tetrahydrofuran (26g, 0.36 mole), 3-ethyl-tetrahydrofuran (13g, 0.13 mole) and dry NAFION catalyst powder (grade NR-50, 3g) were added. The mixture was heated to 60 ℃ under a slow nitrogen flow with stirring. When the system reached 60 ℃, ethylene oxide gas (EO) was slowly added through the gas inlet tube at a rate of about 6 g/h. The addition of EO was continued until a total of 6.5g of EO had been added. The EO feed was then cut off and the gas inlet system was flushed with dry nitrogen. Heating was continued for an additional 15 minutes and the polymerization vessel was then allowed to cool to room temperature.

The polymer solution was separated from the solid catalyst by filtration and any polymer attached to the catalyst was removed by washing with dry methanol. Unreacted monomers were removed from the solution by distillation, and the polymer residue was vacuum-dried at 100 ℃ and 1mmHg (0.13kPa) pressure for 1 hour. Final filtration gave 36 wt% of clear polymer, number average molecular weight determined by endgroup titration 1075, composition determined by NMR analysis as follows:

49 wt% of tetrahydrofuran, with the proviso that,

20% by weight of 3-ethyl-tetrahydrofuran, and

31% by weight of ethylene oxide.

Example 3

This example serves to illustrate the copolymerization of tetrahydrofuran, oxepane and ethylene oxide. A 100 ml round bottom polymerization reactor was equipped with a mechanical stirrer, a dry ice reflux condenser with a desiccated gypsum moisture barrier, a thermometer, and a gas inlet tube. Tetrahydrofuran (10g, 0.14 mole), oxepane (hexamethylene oxide, 10g, 0.1 mole) and dry NAFION catalyst powder (grade NR-50, 2g) were added. 1, 4-butanediol was added as a molecular weight controlling agent. The mixture was heated to 70 ℃ under a slow nitrogen flow with stirring. When the system reached 70 ℃, ethylene oxide gas was slowly added through the gas inlet line at a rate of 4.5 grams per hour. The addition of EO was continued until a total of 9g of EO had been added. The EO feed was then cut off and the gas inlet system was flushed with dry nitrogen. Heating was continued for an additional 15 minutes and the polymerization vessel was then allowed to cool to room temperature.

The polymer solution was separated from the solid catalyst by filtration and any polymer attached to the catalyst was removed by washing with dry methanol. The polymer was separated from the solution by vacuum drying at 100 ℃ and 1mmHg (0.13kPa) pressure for 1 hour. The final filtration gave 45 wt% of clear polymer, number average molecular weight 2420 as determined by end group titration and composition as determined by NMR analysis as follows:

45 wt% of tetrahydrofuran, with the proviso that,

20% by weight of oxepane, and

35% by weight of ethylene oxide.

Example 4

This example serves to illustrate the copolymerization of tetrahydrofuran, 3-methyl-tetrahydrofuran and ethylene oxide.

Tetrahydrofuran (800g, 11.1 moles) and 3-methyl-tetrahydrofuran (100g, 1.15 moles) were charged to a 2-liter 4-neck round bottom polymerization reactor equipped with a mechanical stirrer, dry ice condenser, thermometer and gas inlet tube. 1, 4-butanediol (4g, 0.033 mole) was added as a molecular weight control agent and dry NAFION pellets (grade NR-50, 30g) were added as a polymerization catalyst.

While ethylene oxide was slowly added through the gas inlet tube, the polymerization mixture was stirred and heated to 50 ℃. The ethylene oxide addition was continued until 55g (1.25 moles) had been added over a period of about 4 hours. The ethylene oxide feed was then cut off and the gas inlet system was flushed with nitrogen. Heating was continued for an additional 15 minutes, after which the polymerization vessel was cooled to 35 ℃ and then filtered. The solid catalyst residue is washed and can be recycled. The polymer solution was dried under vacuum at 100 ℃ under a pressure of 2mmHg (0.27kPa) for 1 hour. The final product filtered to give a clear, sticky polymer with the following typical properties:

Mn：2700

viscosity: 10.5 poise (1.05Pa.s) at 40 deg.C

Melting temperature: -3.9 deg.C

Ethylene oxide content: 28 mol%

3-methyl-tetrahydrofuran content: 8 mol% of

Examples 5 to 15

These examples illustrate the copolymerization of tetrahydrofuran, 3-methyl-tetrahydrofuran and ethylene oxide using fluorosulfonic acid (FSA) catalyst.

The procedure for each of these examples (table 1) is as follows: on a dry glass reactor equipped with baffles and a jacket, a thermocouple, sintered glass gas inlets for nitrogen and ethylene oxide, a solid carbon dioxide condenser with an outlet and a mechanical stirrer were installed. 3-MeTHF was added to the flask as a 55% solution of 3-MeTHF in THF with additional THF added to give the monomer addition as shown in Table 1, then cooled to 10-15 deg.C. The flask was purged with nitrogen and fluorosulfonic acid was added dropwise over 3-5 minutes through a dry addition funnel. The reaction mass was then heated to the reaction temperature and ethylene oxide was added over about 3 h. Stirring was performed to maintain the reaction mass at a uniform temperature. The temperature of the progressively tacky contents is allowed to rise to, but not exceed, 45 ℃. The temperature was adjusted by controlling the ethylene oxide feed rate.

To terminate and neutralize the reaction, the carbon dioxide condenser was replaced with a simple distillation head and hot water (600 ml) was added. The flask contents were heated to 100 ℃ to remove the tetrahydrofuran/water distillate. Nitrogen flow was maintained to accelerate distillation. When the tetrahydrofuran was stripped out, the stirring was stopped and the contents were allowed to separate. The aqueous layer was removed and the organic layer was washed twice with 600 ml of hot water. After the second wash, 15g of calcium hydroxide was added with thorough stirring, additional water was precipitated and removed. Additional calcium hydroxide was added in small portions until the pH was 7-8. The polymer mixture was maintained at 80 ℃ to maintain low viscosity.

To isolate the polymer, the neutralized wet polymer was stripped under vacuum at 90 ℃. The solids were removed by filtration through a pad of celite on Whatman #1 filter paper on a steam heated buchner funnel. The haze-free polymer is weighed, the molecular weight is determined by end group titration and¹h NMR was used to determine the composition. These data are summarized in Table 2.

Table 1.

Examples	THF(g)	EO(g)	3-MeTHF(g)	FSA(g)	Rxn time (hr)	Rxn temperature (. degree. C.)
							5	663	37.1	176	37.1	4.4	40
6	663.6	37.1	176.4	37	2.3	30.1-34.6
							7	663.6	37	176.4	37.2	2.3	30.7-39.2
8	663.6	37	176.4	37.7	4	34.4-41.2
							9	1448	81	385	80.8	4	35-40
10	1448	53.2	385	80.8	4	35
							11	2949	204	647	141.4	4	35-41
12	2949	204	647	141.4	4.25	32-42
							13	2768	204	792	75.1	4	25-32
14	2768	204	792	74.6	3.7	15-22
							15	2768	204	792	75.9	4.5	10.5-31

Rxn in the above table refers to the reaction

Table 2.

Examples	Conversion rate	％EO	％3-MeTHF	Mn	Melting Point (. degree.C.)
						5	56	4.8	9.5	1804	14.8
6	52.9	5.0	10.0	2166	7.79
						7	NA	4.4	9.3	2244	9.89
8	63.9	5.4	9.6	1657	7.39
						9	51.6	4.7	9.6	1778	16.15
10	51.1	2.9	9.3	1996	17.89
						11	56.2	6.4	9	2274	17.18
12	50.6	7	9	2000	16.14
						13	4.2	11.8	8.1	843	14.97
14	2.9	13.3	11.3	660	4.21
						15	16.3	9	11.2	1085	11.05

Examples 16 to 20

These examples illustrate the copolymerization of tetrahydrofuran, 3-methyl-tetrahydrofuran and ethylene oxide using an anhydrous phosphotungstic acid (PTA) catalyst.

A5-L reactor equipped with baffles and a jacket was equipped with a thermocouple, ethylene oxide and nitrogen inlets, with N₂An outlet dry ice condenser and a mechanical stirrer. The apparatus is passed through N at 100 DEG C₂And blowing and drying. Tetrahydrofuran, water and anhydrous PTA were added to the flask and cooled (see table 3). 3-MeTHF was added to the flask as a 55% solution of 3-MeTHF in THF with additional THF added to give the monomer addition as shown in Table 3, then cooled to 10-15 deg.C. The reactor was purged with nitrogen and the stirrer was set to 250 rpm. Ethylene oxide was added steadily over about 2 to 4 hours while cooling to maintain the specified reaction temperature. After all of the ethylene oxide was added, stirring was continued until the total reaction time was complete. After the reaction, 1L of deionized water was added and the mixture was stirred at 45 ℃ for at least 30 minutes.

The crude copolymer was purified by the following steps: the reaction mixture was diluted with an equal volume of methanol at 45 ℃ and the methanol solution was passed through a column packed with a weak base ion exchange resin to adsorb the acid catalyst. Unreacted tetrahydrofuran, methanol and water were then removed in vacuo. The solids were removed by filtration through a pad of celite on Whatman #1 filter paper on a steam heated buchner funnel. The haze-free polymer is weighed, the molecular weight is determined by end group titration and¹h NMR was used to determine the composition. These data are summarized in Table 4.

Table 3.

Examples	THF(g)	EO(g)	3-MeTHF(g)	PTA(g)	Rxn time (hr)	Rxn temperature (. degree. C.)	EO addition time (hr)
								16	2808	178	792	130	4.1	-4-4	3.1
17	2808	178	792	75.6	4	-4.4-1.5	2.9
								18	2943	70.8	657.3	75.6	6	-4.8-0.4	2.33
19	2943	123	657	75.6	5	-1-3.6	3.83
								20	2988	162	612	75.6	5	14-22	4.8

Table 4.

Examples	Conversion rate	％EO	％3-MeTHF	Mn	Melting Point (. degree.C.)
						16	59	14.6	12	3420	-0.37
17	53.6	14.45	12.9	4438	-3.21
						18	26.7	15.2	10.2	2233	4.46
19	46.6	13.9	10.35	2194	7.37
						20	66.3	12.1	8.6	4180	10.02

Example 21

This example serves to illustrate the copolymerization of tetrahydrofuran, 2-methyl-tetrahydrofuran and ethylene oxide. A 250 ml round bottom polymerization reactor was equipped with a mechanical stirrer, a dry ice reflux condenser with a desiccated gypsum moisture barrier, a thermometer, and a gas inlet tube. Tetrahydrofuran (THF, 25g, 0.35 mole), 2-methyl-tetrahydrofuran (75g, 0.75 mole) and dry NAFION catalyst powder (grade NR-50, 6.5g) were added. The mixture was heated to 60 ℃ under a slow nitrogen flow with stirring. When the system reached 60 ℃, ethylene oxide gas (EO) was slowly added through the gas inlet line at a rate of about 6 grams per hour. The addition of EO was continued until a total of 17g of EO had been added. The EO feed was then cut off and the gas inlet system was flushed with dry nitrogen. Heating was continued for an additional 15 minutes and the polymerization vessel was then allowed to cool to room temperature.

The polymer solution was separated from the solid catalyst by filtration and any polymer attached to the catalyst was removed by washing with dry methanol. The polymer was separated from the solution by vacuum drying at 100 ℃ and 1mmHg (0.13kPa) pressure for 1 hour. Final filtration gave 30 wt% of clear polymer, a molecular weight of 2000 as determined by end group titration, and had the following composition:

25 wt% of tetrahydrofuran, the amount of which is,

40% by weight of 2-methyl-tetrahydrofuran, and

35% by weight of EO to the reaction mixture,

the above data were determined by NMR analysis.

Claims (7)

1. A copolymer comprising constitutional units derived by polymerization of tetrahydrofuran, ethylene oxide and at least one additional cyclic ether, wherein the additional cyclic ether is selected from the group consisting of 2-methyl-tetrahydrofuran, 3-ethyl-tetrahydrofuran, oxepane, 3, 4-dimethyl-tetrahydrofuran and perfluoroalkyl-ethylene oxide.

2. The copolymer of claim 1, wherein the molar concentration of the constituent units derived from ethylene oxide is from 1% to 60%.

3. The copolymer of claim 2, wherein the molar concentration of the constituent units derived from ethylene oxide is from 3% to 35%.

4. The copolymer of claim 1, wherein the molar concentration of constitutional units derived from the additional cyclic ether is 3% to 40%.

5. The copolymer of claim 4, wherein the molar concentration of constitutional units derived from the additional cyclic ether is 5% to 30%.

6. A polyurethane polymer comprising the reaction product of at least one organic polyisocyanate compound and a copolymer diol comprising constitutional units derived by copolymerization of tetrahydrofuran, ethylene oxide and at least one additional cyclic ether, wherein the additional cyclic ether is selected from the group consisting of 3-methyl-tetrahydrofuran, 3-ethyl-tetrahydrofuran, oxepane, 3, 4-dimethyl-tetrahydrofuran and perfluoroalkyl-ethylene oxide.

7. A spandex filament comprising the polyurethane polymer of claim 6.