CA2135293A1

CA2135293A1 - Hard thermoplastic polyurethane elastomers

Info

Publication number: CA2135293A1
Application number: CA002135293A
Authority: CA
Inventors: James M. O'connor; John W. Reisch; Curtis P. Smith
Original assignee: Individual
Current assignee: Olin Corp
Priority date: 1992-06-04
Filing date: 1993-05-20
Publication date: 1993-12-09
Also published as: KR100259667B1; JP3326176B2; KR950701943A; WO1993024549A1; EP0643733A1; EP0643733A4; AU4384193A; JPH07507344A

Abstract

This invention relates to a method of fabricating a thermoplastic elastomer which comprises the steps of: (a) fabricating a polyol blend having a desired polydispersity and comprising a first polyol and a second polyol, a diisocyanate, and a difunctional, isocyanato-reactive chain-extender, the first polyol being prepared utilizing a double metal cyanide complex catalyst and having a molecular weight of between about 1,000 and about 5,000, said first polyol having an end group unsaturation level of no greater than 0.04 milliequivalents per gram of polyol, the second polyol being a polyether polyol having an average molecular weight of between about 1,000 and about 20,000, (b) reacting said polyol blend with a diisocyanate to produce an isocyanate-terminated prepolymer, and (c) reacting said isocyanate-terminated prepolymer with a difunctional isocyanato-reactive chain extender in a mold or in an extruder in order to produce a hard elastomer characterized by a hardness of between a 75 Shore A and about a 75 Shore D. Also claimed is the elastomer produced by the above method utilizing a one-shot technique.

Description

W093/24549 ~13~,293 PCI/US93/04785 .. l i' HARD THERMOPLASTIC POLYURETHANE ELASTOMERS

The present invention relates generally to the production of thermoplastic polyurethane ("TPU") elastomers and polyurea elastomers having high hardness and, more specifically, to the production of elastomers utilizing a polyol blend containing a low unsaturation level polyol prepared using a double metal cyanide complex catalyst. ;
The use of double metal cyanide (so-called ~DMCn) catalysts in the preparation of high molecular weight lQ polyols is well-established in the art. For example, U.S. Patent 3,829,505, assigned to General Tire & Rubber Company, discloses the preparation of high molecular weight diols, triols etc., using these catalysts. The polyols prepared usin~ these catalysts can be fabricated to have a higher molecular weight and a lower amount of end group unsaturation than can be prepared using commonly-used KOH catalysts. The '505 patent discloses that these high molecular weight polyol pro~ucts are useful in the preparation of nonionic surface active agents, lubricants and coolants, t~tile sizes, packaging films, as well as in th preparation of solid f or fle~ible polyurethanes by reaction with polyisocyanates.
Certain thermoset polyurethane elastomers produced using triols made by DMC catalysis are also known. More specifically, U.S. Patent 4,242,490 W093/24s49 PCT/US93~04785 ~1 JS ~ 9 3 -2- ;

discloses the preparation of such elastomers by react~ng a DMC catalyst-prepared polypropylene ether triol having a molecular weight of from 7,000 to 14,000, ethylene glycol, and toluene diisocyanate in a specificd range of molar ratios using either a prepolymer process or a "one-shot~ process.
Methodology for preparing TPU elastomers is well-established in the art. By way of illustration, U.S. Patent 4,202,957 discloses polyurethane polyether-based elastomers, made usin~ a select group of polypropylene oside-polyethylene o~ide block copolymers, which this patent states are thermoplastic, recyclable and possess high temperature degradation resistance thus permitting fabrication by injection molding.
As another illustration, U.S. Patent 5,096,99~
discloses the production of TPU elastomers made using DMC-prepared polyether polyols. These elastomers are disclosed in the '993 patent as having e~cellent physical and chemical properties.
Unfortunately, hard TPU elastomers, such as those elastomers having a hardness within the range of between 75 Shore A and about 75 Shore D, prepared in accordance with prior art methods utilizing a DMC-prepared polyol are generally not as readily estruded into shaped articles as might be desired. Accordingly, new methodology for producing hard elastomers having e~cellent physical and chemical properties made using DMC-prepared polyol(s) in a readily extrudable elastomer-forming composition would be highly desired by ?- ' 30 the elastomer manufacturing community. The present ~ ;
invention provides such desired methodology.
In one aspect, the present invention relates to a thermoplastic polyurethane or polyurea elastomer made by "
reacting in a ~one-shot~ process (preferably a ~

W 0 93/24549 21~S2~ PC-r/US93/04785 S, continuous one-sbot process) a polyol blend ot polyether polyols comprising a first polyol and a second polyol, a ~ :~
: diisocyanate, and a difunctional, isocyanato-reactive ~.
chain-estender, the irst polyol being prepared ;-utilizing a double metal cyanide comples catalyst and - having a molecular weight of between about 1,000 and : about 5,000 ~advantageously between 1,500 and 4,000, more advantageously between 1,500 and 2,500), said first ~: polyol having an end group unsaturation level of no :~ 10 greater than 0.04 (preferably less than 0.02, more preferably less than 0.01) milliequivalents per gram of - polyol, the second polyol being a polyether polyol having an average molecular weight of between about 1,000 and about 20,000 (advantageously between 1,000 and 4,000, more advantageously between 1,000 and 4,000), the second polyol being present in an amount of between about 5% and about 50% based upon the weight of said polyol blend, with the proviso that the average molecular weight of said second polyol is different from :; ; 20 the average molecular weight of said first polyol, and with the additional proviso that the polydispersity of said polyol blend is greater than the polydispersity of said first polyol, the polydispersity of said polyol blend being between about 1.05 and about 3.0 tpreferably between 1.1 and 1.5, more preferably between 1.1 and 1.2), the equivalent ratio of NCO groups on said .
diisocyanate to active hydrogen groups;on said polyol plus chain e~tender being between about 1:0.7 and about 1:1.3 (preferably between 1:0.9 and 0.9:1, more ~;
preferably between 1:0.95 and 0.95:1), and the molar ~ `
ratio of chain estender to polyol being between about 0.15:1 and about 75:1, said elastomer having a hardness of between a 75 (preferably at least 80) Shore A and about a 75 (preferably no greater than 65, more W093/24549 PCT/US93/04785 ~ ~
' I 3.~3.~ 9 3 r l;
i i, preferably no greater than 55) Shore D. Preferably,~the first polyol and the second polyol are each polyether ', diols.
In another aspect, the presellt invention relates to a thermoplastic polyurethane or polyurea elastomer : made by reacting an isocyanate-terminated prepolymer with a difunctional isocyanato-reactive chain-extender, the isocyanate-terminated prepolymer being the reaction product of a polyisocyanate and a polyol blend of polyether polyols comprising a first polyol and a second polyol, the first polyol being prepared utilizing a double metal ¢yanide complex catalyst and havinq a molecular weight of between about l,000 and about 5,000 ~: :(advantageously between l,500 and 4,000, more advantageously between l,500 and 2,500), said first polyol having an end group unsaturation level of no greater than 0.04 (preferably less than 0.02, more : ~ preferably less than O.Ol) milliequivalents per gram of - polyol, the second polyol being a polyether polyol having an average molecular weight of between about l,000 and about 20,000 (advantageously between l,000 and :
- 4,000, more advantageously between l,0~0 and 4,000), the `
~ second polyol being present in an amount of between : about 5~ and about 50% based upon the weight of said ~: polyol blend, with the proviso that the average molecular weight of said second polyol is different from : the average molecular weight of said first polyol, and with the additional proviso that the polydispersity of ;:
: said polyol blend is greater than the polydispersity of ~ `~
said first polyol, the polydispersity of said polyol blend being between l.09 and about 3.0 (preferably . :`
between l.l and l.S, more preferably between l.l and 1.2), the equivalent ratio of NCO groups on said diisocyanate to active hydrogen groups on said polyol W093/24s49 ~1352S ~ PCT/US93/~78~ ~

_5_ plus chain extender being between about 1:0.7 and about 1:1.3 (preferably between 1:0.9 and 0.9:1, more : preferably between 1:0.95 and 0.95:1), and the molar - ratio of chain extender to polyol ~eing between about 0.15:1 and about 75:1, said elastomer having a hardness of between a 75 (preferably at least 80) Shore A and about a 75 (preferably no greater than 65, more preferably no greater than 55) Shore D. Preferably, the first polyol and the second polyol are each polyether diols.
- In yet another aspect, the present invention relates to a method of fabricating a thermoplastic elastomer which comprises the steps of:
(a) fabricating a polyol blend of polyether ~:; 15 polyols comprising a first polyol and a second polyol, the first polyol being prepared utilizing a double metal :~
cyanide complex catalyst and having a molecular weight : of between about 1,000 and about 5,000 (advantageously between 1,500 and 4,000, more advantageously between 1,500 and 2,500), said first polyol having an end group unsaturation level of no greater than 0.04 (preferably . less than 0.02, more preferably less than 0.01~
: milliequivalents per gram of polyol, the second polyol being a polyether polyol having an average molecular weight of between about 1,000 and about 20,000 (advantageously between 1,000 and 4,000, more advantageously between 1,000 and 4,000), the second polyol being present in an amount of between about 5%
and about 50% based upon the weight of said polyol 30 blend, with the proviso that the average molecular ~ :
weight of said second polyol is different from the average molecular weight of said first polyol, and with .
the additional proviso that the polydispersity of said polyol blend is greater than the polydispersity of said ~:

W 0 93/24549 ~ 1 3 ~ 2 ~ 3 PCT/US93/047B5 -6- :

flrst polyol, the polydispersity of said polyol blend~
being between about 1.05 and about 3.0 (preferably between 1.1 and 1.5, more preferably between 1.1 and 1.2), (b) reacting said polyol blend with a diisocyanate to produce an isocyanate-terminated prepolymer, and (c) reacting said isocyanate-terminated prepolymer with a difunctional isocyanato-reactive chain extender in a mold or in an estruder in order to produce a hard elastomer characterized by a hardness of between a 75 (preferably at least 80) Shore A and about a 75 (preferably no greater than 6S, more preferably no ; greater than S5) Shore D, with the proviso that when the lS molecular weight of the polyol is less than 4,000, then the polyol has an ethylene o~ide content of less than 35 weight based upon the weight of the polyol. Preferably, ~ the polyol blend has an average ethylene o~ide ("EO~) ;- content as a cap of between about 0~ and about ~5~, preferably between 5% and 30%, more preferably between 10% and 25%, based upon the total weight of the polyol blend. Preferably, the first polyol and the second poIyol are each polyether diols. `
These and other aspects will become apparent upon reading the following detailed description of the invention.
It has now been surprisingly found that hard, readily e~trudable thermoplastic elastomers having a hardness in the range of between a 75 Shore A and a 75 30 Shore D, and fabricated using at least one polyol made ~-using a DMC catalyst, are suitably produced in accordance with the present invention. The elastomers are produced utilizing a polyol blend containing at least one polyol prepared using a double metal cyanide W093/24549 2 1 3 5 ~ ~, 3 PCT/~S93/~785 ~ ~

-7- ~
i comple~ catalyst. These elastomers e~hibit escellent~
physical and chemical properties. The elastomers possess e~cellent structural strength and stability characteristics. In addition, the eiastomers are recyclable and can be re-extruded and remolded if desired.
The present invention is particularly surprising because previous efforts to produce such hard elastomers by the present inventors using made with a DMC catalyst have resulted in poorly e~trudable elastomers-forming polymers which tend to "slam-up" or crystallize in colder portions of the extruder or die during e~trusion processing. Instead of the desired clear, transparent, est~ruded film one obtains an undesired hazy, milky film that may contain random chunks of hard material.
Without wishing to be bound to any particular theory, it is believed by the present inventors that such poor extrudability is attributable to the narrow molecular ~
- weight distribution of polyols made using DMC -catalysts. The present invention provides a solution to ~; this extrudability problem, and this solution is believed to be attributable to the enhanced mol~:cular weight distribution or polydispersity associated with the polyols employed in the present invention.
` The thermoplastic elastomers of the present invention may be made by the prepolymer process or the one-shot process. The polyurethane isocyanate-terminated prepolymer that is utilized when employing the prepolymer process according to the invention is ~ ~
30 prepared by reacting an organic polyisocyanate with a ~ `
polyalkylene ether polyol(s) in an equivalent ratio of NCO to OH groups of from about lS:l and about l.2:l (preferably between 7:l and 3:l), using standard procedures, to yield an isocyanate-terminated prepolymer ~ 352~3 o~ controlled molecular weight. The reaction may be ~ ¦
accelerated by employing a catalyst; common urethane ~- catalysts are well known in the art and include numerous organometallic compounds as well as am~nes, e.g., tertiary amines and metal compounds such as lead ~^~ octoate~s, mercuric succinates, stannous octoate or dibutyltin dilaurate may be used. Any catalytic amount may be employed; illustratively, such amount varies, depending on the particular catalyst utilized, from about 0.01 to about 2 percent by weight of the polyurethane prepolymer.
The polyol blend comprises at least a first polyol and a second polyol, and additional polyols may be~employed in the blend as desired. The preferred l5~polyol blends consist essentially of two or three polyols. Preferred polyol reactants are the polyether ~ dio~ls and combinations thereof. Suitable polyether s~ diols include various polyo~yalkylene diols and combinations thereof, preferably containing ethylene oxide (~E0~) in an amount of between about 5 and about 40, more preferably between about 15 and about 30, ``
weight percent based upon the weight of the polyol.
Suitable diols preferably have a primary hydro~yl content of between about 30 and about 95%, more 25 preferably between about 50 and about 95%. The ~`
ethylenic unsaturation level for the polyol is preferably no greater than 0.04, more preferably less '~~ `
than 0.025, milliequivalents per gram of polyol. It is !''' preferred that any residual alkali metal catalyst in the 30 polyol be no greater than 25 ppm, more preferably no ~-greater than 8 ppm, most preferably no greater than 5 ~ ppm. The potential adverse effects of residual alkali ;~ metal catalyst in the polyol can be overcome by W O 93/24549 ,~ 1 3 ~ PC~r/US93/04785 neutralizing with an effective amount of an acid, such as phosphoric acid. , The polyols can be prepared, according to 5 well-known methods, by condensing an alkylene o~ide, or 5 a mixture of alkylene o~ides using random or step-wise addition, with a polyhydric initiator or mixture of initiators. Illustrative alkylene o~ides include ethylene o~ide, propylene oxide, butylene o~ide, amylene o~ide, aralkylene 02ides such as styrene o~ide, and the 10 halogenated alkylene oxides such as trichlorobutylene oxide and so forth. The most preferred alkylene o~ide is propylene o~ide or a mixture thereof with ethylene oxide using random or step-wise oxyalkylation.
The polyhydric initiator used in preparing the 15 polyether diol reactant includes the following and mi~tures thereof: ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, butane diols, pentane diols, water, combinations thereof, and the like.
The alkylene o~ide-polyhydric initiator condensation reaction is preferably carried out in the presence of a double metal cyanide catalyst. Without wishing to be bound by any particular theory, it is speculated by the present inventor that unsaturated end groups result in monoCunctional species that act as chain stoppers in elastomer formation. In polyol synthesis with KOH catalysis, the unsaturation formed increases as a direct function of equivalent weight.
Eventually conditions are establ;shed wherein further ~-propylene oxide addition fails to increase the molecular weight. In other words, the use of alkali catalysts to produce high molecular weight, hydro~y terminated polyoxypropylene ethers results in a substantial loss in hydroxy functionality. With dou~le metal cyanide W093/24549 PCTtUS93/0478S
~ 13 .~

i catalysis, much less unsaturation is formed allowing ~ , higher equivalent weight polyols to be prepared.
` The double metal cyanide complex class catalysts suitable for use ahd their preparation are described in U.S. Pat. Nos. 4,472,560 and 4,477,5B9 to Shell Chemical Company and U.S. Pat. Nos. 3,941,849; 4,242,490 and 4,335,188 to The General Tire & Rubber Company.
One double metal cyanide comple~ catalyst found particularly suitable for use is a zinc , ~ 10 he~acyanometallate of formula:
. ~ .

3[M(cN)6]2.szncl2~yGLyME~zH2o wherein M may be Co(III), or Cr(III) or Fe(II) or Fe(III); ~, y, and z may be fractional numbers, integers, or zero and vary depending on the e~act method of preparation of the comple~.
~; The second component of the polyol blend having a ;
different molecular weight, either higher or lower or a mixture of both high and low, in order to widen the ~; ~ moIecular weight distribution. A measure of the ;~
molecular weight distribution, polydispersity, is measured on a suitable GPC or HPSEC column or set of columns and is related to the ratio of the weight-average molecular weiqht and the number-average molecular weight, MW~Mn. A MW/Mn of 1.054 or ~ `
lower does not allow the formation of a suitable estrusion grade polymer while a MW/Mn between 1.054 and 3.5 (preferably between 1.10 and 3.0, more preferably between 1.10 and 2.5) yields desirable ~!
materials.
,.
' .

W093/24549 ~ 2~3 PO/US93/oJ78s Any suitable organic diisocyanate, or mi~ture of diisocyanates, may be used in the elastomer-forming process of the present invention. Illustrative are toluene diisocyanate, such as the 80:20 and the 6S:35 mi~tures of the 2,4- and 2,6-isomers, ethylene .- .
diisocyanate, propylene diisocyanate, methylene-bis -(4-phenyl) isocyanate (also referred to as diphenylmethane diisocyanate or MDI), dibenzyl ~
diisocyanate, ~ylene diisocyanate (XDI), isophorone ~-diisocyanate (IPDI), 3,3'-bistoluene-4,4'-diisocyanate, hexamet~hylene diisocyanate (HDI), hydrogenated MDI, hydrogenated XDI, cyclohe~ane diisocyanate, paraphenylene diisocyanate, mi~tures and derivatives thereof, and the like. Other advantageous embodiments of the invention suitably employ an isomeric mi~ture of 2,4- and 2,6-toluene diisocyanate in which the weight ;`
ratio of the 2,4-isomer to the 2,6-isomer is from about 60:40 to about 90:10, and more preferably from about 65:35 to about 80:20, as well as MDI.
Chain estenders useful in the present invention include diols and diamines such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butane diol, pentane diol, 3-methylpentane-l,S-diol, hexane diol, osyalkylated hydroquinone, resorcinol and bisphenol A, hydrogenated bisphenol A, 1,4-cyclohesane dimethanol, or polyalkylene o~ide diols with molecular weights between 100 - 500, diethyltoluene diamine, ethylene diamine, 4,4'-methylene bis(2-chloroaniline) (~MOCAn), hydrazine, substituted aromatic diamines such ~;
30 as the product cGmmercially available as UNILINK 4200, a <
product of UOP, Inc., N,N-bis~2-hydrosypropyl)-aniline which is commercially avail-ble as ISONOL 100, a product of Dow Chemical Corp., and ~he like, and combinations thereof. The chain e~tension can be conducted either in W O 93/24549 . PC~r/US93/04785 2 1 r3 ~ 3 -12~

situ during the prepolymer formation or in a separate~ ¦
reaction step.
In preparing the polyurethane and/or polyurea ~
elastomer, the polyether polyol~s), polyisocyanate(s), '' 5 chain e~tender(s), and other components are reacted, '-typically under conditions of an elevated temperature.
A preferred method of forming the desired thermoplastic ~'' elastomers is by continuous processing utilizing an '-'' extruder as illustrated by U.S. Patent 3,642,964. An -alternative method involves batch processing, followed by grinding and e~trusion of the formed elastomer as is well-known in the art. Although either the prepolymer method or the one-shot method can be used, the one-shot method is preferred. The one-shot method is intended to ¦ 15~ also include the process whereby the diisocyanate has been converted to a quasi-prepolymer by reaction with a minor amount (i.e., less than about lO percent on an ' equivalent basis) of polyol prior to carrying out the '' polyurethane forming reaction. ' In preparing the elastomer, urethane forming catalysts can be used as well'as the'usual compounding ~' ingredients such as antiosidants or other antidegradants. Typical antio~idants include hindered phenols, butylated hydrosytoluene (~BHT"), and the like. Other optional compounding ingredients include, for e~ample, plasticizers, adhesion promoters, fillers and pigments like clay, silica, fumed silica, carbon black, talc, phthalocyanine blue or green, TiO2, U-V
absorbers, MgC03, CaC03 and the like. The compounding 30 ingredients, such as fillers, are suitably employed in ~ ~' the elastomer in an amount of between O and about 75 weight percent based upon the weiqht of the elastomer. ' The polymerization reaction may be carried out in a W 0 93/24549 21,S~3 PC r/US93/04785 single reaction (one-shot process), or in one or mor~
sequential steps (prepolymer process), using either bulk polymerization or solution polymerization. When l soiution polymerization is used, polar solvents such aS ;~
tetrahydrofuran (nTHF~)/ dimethylformamide (~DMFn), and dimethylacetamide (nDMAC") are typically utilized. In -the one-shot process, all the isocyanate-reactive `-components are reacted simultaneously with the polyisocyanate. In such process, it is normal practice to blend all components except the polyisocyanate into a ~ side" mixture, which is then reacted with the polyisocyanate to form the polyurethane and~or polyurea elastomer. However, the order of mixing is not critical ~-as long as the components do not undesirably react before all components are present. The reaction mixture is usually then placed in a mold, or extruded through an extruder, and cured at a suitable temperature. The apparatus used for blending and molding is not especially critical. Hand mixing, conventional machine mixing, and the so-called reaction injection molding (RIM) equipment are all suitable. In the prepolymer process, all or a portion of one or more of the isocyanate reactive materials is reacted with a stoichiometric excess of the polyisocyanate to form an isocyanate-terminated prepolymer. This prepolymer is then allowed to react with the remaining isocyanate-reactive materials to prepare the polyurethane and~or `
polyurea elastomer. The prepolymer can be prepared with , either the polyether or the chain extender, or a mixture 30 of both. ~-The mi~ing of the reactants can be carried out at ambient temperature (of the order of 25C.) and the resulting mi~ture is then heated to a temperature of the order of about 40C. to about 130C., preferably to a . .: .
. ~ . ~ .... . ..

W O 93/24S49 PCT~US93/04785 ~ `
~! ~ j"" ~
213~293 -14- '`

temperature of about 90C. to about 120C Alternatively, and preferably, one or more of the reactants is preheated to a temperature within the above ranges before the admising is carried ou.... Advantageously, in -a batch procedure, the heated reaction components are -subjected to degassing in order to remove entrained bubbles of air, water, or other gases before the reaction takes place. This degassing is accomplished conveniently by reducing the pressure under which the components are maintained until no further evolution of bubbles occurs. The degassed reaction components are then admixed and transferred to suitable molds or extrusion equipment or the like and cured at a temperature of the order of about 20C. t~ about 115C.
15 The time required for curing will vary the temperature `
of curing and also with the nature of the particular composition, as is known in the art.
As used herein, the terms ~molecular weight" and "average molecular weight" are intended to designate ; 20 weight average molecular weight. ~Polydispersity" is defined as the weight-average molecular weight divided by the nùmber-average molecular weight.
While the invention has been described above with reference to specific embodiments thereof, it is apparent that many changes, modifications and variations can be made witbout departing from the inventive concept disclosed herein. Accordingly, it is intended to embrace all such changes, modifications and variations that fall within the spirit and broad scope of the appended claims.

W O 93/24549 2 1 3 . ?. ~ ~ PC~r/US93/0478S

SPECIFIC EXAMPLES
~` .' ':
I. PREPARATION OF HIGH MOLECULAR WEIGHT POLYOL WITH LOW
UNSATURATION ~.

A 2 gallon autoclave was filled with 550 g. of POLY-G~ 20-112, a polyoxypropylene diol of molecular weight 1000, and 2.2 g. of a double metal cyanide catalyst. The catalyst is a Zinc Cobaltihexacyanate complex with 1,2-dimethoxyethane (glyme). The reactor was closed, flushed three times with nitrogen and then heated to 100C. At that time a total of 150 g.
propylene oxide was added and after 20 min. the reaction started, as evidenced by a pressure drop. Then propylene oxide, 3850 9. was added over a period of 4 hrs at a propylene oxide partial pressure of 30 psi.
When the pressure dropped to 10 psi. KOH, 16 9., was introduced into the reactor and then ethylene oxide, 680 9., was allowed to react at 70 psi for 5 hrs. The unreacted ethylene oxide was vented and the reactor cooled and opened up. To the reactor was added magnesium silicate, 100 9., and Supercell filter aid, 100 9. The contents of the autoclave were then heated to 100C for 2 hrs., after which time a vacuum of 25"
water was applied for 1 hr. The polyol was then pushed through a small preheated filter press, containing a 5 `~
micron paper filter, at ~0 psi. and 100C. Analysis showed that the polyol contained 9% ethylene oxide, had an OH # of 16 mg XOH/g. and had 70% primary OH. The unsaturation value was 0.0175 meq/g. and the Zn, Co and K contents were below 2 ppm.

W093/24549 ; ~ PCT/US93/04785 ~ -:
213 ~ 2 .~ .~
- 16- !

~, .

II. PREPARATION OF A 4000 MOLECULAR WEIGHT LOW
UNSATURATION CONTAINING POLYOL (OH# 28.3, MW 3965) In a preparation similar to I. abov~ a polyol was prepared where analysis showed that the material contained 20% ethylene o~ide and had an OH ~ of 28. 3 mg KOH~g. The unsaturation value was 0.005 meq/g. and the residual KOH was 0.0 ppm.

III. PREPARATION OF A 2000 MOLECULAR WEI~HT LOW
UNSATURATION CONTAINING POLYOL (OH# 50.1 MW 2240~ ;

In a preparation similar to I. above a polyol was prepared where analysis showed that the material contained 24.6% ethylene oxide, 75.6% primary OH and had an OH # of 50.1 mg KOH~g. The unsaturation value was 0.007 meq/g. and the KOH residue was 0.20 ppm.

PREPARATION OF A THERMOPLASTIC POLYVRETHANE - 30% Hard Segment A 2000 ml resin flask was charged with 1100 9., 0.491 moles, of the polyol (OH# 50.1). In addition, 1,4-butanediol, 138.8 9., 1.54 mole, and less than 1 wt%
of a mi~ture of phenolic antioxidant, ester mold release and other processing aids were added. The mixture was dehydrated at 85C in vacuo, 1-2 mm Hg, for two hours after which time period 300 9. increments were weighed out and placed in a 90C oven prior to mi~ing with the isocyanate.

Reaction with Diphenylmethane Diisocyanate Diphenylmethane diisocyanate, MDI, 125.5 9., 0.502 mole, increments were weighed out and maintained at 90C prior to mixing. To prepare the thermoplastic W093/24549 21.,',~3 PCT/US93/0478s ~ ~

polyurethane stannous octoate, 0.14-0.18 g. were added~
to the polyol samples and mixed. The MDI was then added ~ ;
and the mixture rapidly stirred until it thickens (10-15 sec) at which point it is then poured into a Teflon*
coated pan and allowed to cure. After curing the elastomer is granulated, dried at 100~C and 0.3 mm Hg for 14-18 hrs.
The dried polymer is compression molded at 420F. Specimens for tensile, die C and split tear were die cut from the molded plaques after standing 5 days at ambient temperature. An elastomer of 79 Shore A
hardness and 5512 psi tensile strength is obtained.
The dried polymer is e~truded in a 3/4" e2truder through a 4" film die at a profile of: zone 1, 195C;
zone 2, 202C; zone 3, 203C; die, 209C. The resulting cloudy tape has 300% modulus of 1200 psi and ultimate tensile strength of 4500 psi.

PREPARATION OF A THERMOPLASTIC POLYURETHANE - 35~ Hard Segment A 2000 ml resin flask was charged with 1200 9., 0.536 moles, of vacuum dried polyol (OH# 50.1). In addition, 1,4-butanediol, 190.2 9., 2.11 mole, and less than 1 wt% of a mixture of phenolic antioxidant, ester mold release and other processing aids were added. The mixture was dehydrated at 85C in vacuo, 1-2 mm Hg, for two hours after which time period 300 9. increments were weighed out and placed in a 90C oven prior to mixing with the isocyanate.

Reaction with Diphenylmethane Diisocyanate Diphenylmethane diisocyanate, MDI, 157.9 9., 0.631 mole, increments were weighed out and maintained , _.. . . ~ .
. ~ . ~ .. . , . ~ .

213529.~

,' at 90OC prior to mi~ing. To prepare the thermoplastic~
polyurethane stannous octoate, 0.05-0.10 g. were added to the polyol samples and mixed. The MDI was then added and the mixture rapidly stirred ~ntil it thickens (10~
5 sec) at which point it is then poured into a Teflon* -coated pan and allowed to cure. After curing the elastomer is granulated, dried at 100C and 0.3 mm Hg for 14-18 hrs.
The dried polymer is compression molded at 420-430F. The plaques were hazy and appeared to be inhomogeneous, with areas of clear polymer and areas of white, opaque material.
The dried polymer is e~truded in a 3/4" extruder through a 4" film die at a profile of: zone 1, 190C;
zone 2, 195C; zone 3, 195C; die, 208~C. After a short extrusion period, where a cloudy, white tape resulted, the material crystallized in the barrel of the extruder. Starting with a profile of: zone 1, 190C;
zone 2, 200C; zone 3, 200C; die, 212C the melt viscosity is too low to allow a film to form.
, PREPARATION OF POLYOL ~LENDS

The polyol blends listed in Table 1 were made by mixing the indicated parts by weight of the different polyols and then determining the hydroxyl number (OH#), weight average molecular weight (Mw) and polydispersity (MW/Mn) of the polyol blend prior to making the thermoplastic polyurethanes. The ¦ `
- po`lydispersity was measured by GPC chromatography, !`
whereas the molecular weight of the blend was calculated 30 based upon the hydro~yl numbers of the individual polyols (polyols A, B, and C) employed in prodùcing the various polyol blends. ` -W 0 93/24549 2 1 3 ~ 2 9 .~ PC~r/US93/04785 TA~LE 1. Polyol ~lends - Parts by Weight Individual Polyol Bl~nd Cha~ac~eristics A B
PolyolOH~ OH# OHl~ OH# of MW MW/Mn Blend112.7 50.1 27.g Blend 0 100 0 50.1 2240 1.054 II 10 90 0 57.7 1944 1.106 III 20 80 0 57.2 1962 1.165 IV 0 90 10 48.5 2313 1.091 V o ~0 20 46.6 2408 1.165 VI 5 90 5 54.4 2062 1.103 VII 10 80 10 54.2 2070 1.173 * Polyol made by conventional (KOH) catalysis, not DMC
catalysis PREPARATION OF A THE~MOPLASTIC POLYURETHANE - 35~6 Hard Segment - Polyol Blend V

A 2000 ml resin flask was charqed with llOQ 9.
of the polyol blend V and vacuum dried polyol. In addition, 1,4-butanediol, 173.1 9., 1.92 mole, and less than 1 wt% of a mi~ture of phenolic antio~idant, ester mold release and other processing aids were added. The mi~:ture was dehydrated at 85C in vacuo, 1-2 mm Hg, for two hours after which time period 300 9. increments were weighed out and placed in a 90C oven prior to mi~cing ~.
with the isocyanate. :

Reaction with Diphenylmethane Diisocyanate ' Diphenylmethane diisocyanate, MDI, 143.0 9., 0.571 mole, increments were weighed out and maintained 1... ` ,;
W093/24s49 PCT/US93/04785 ~ ~-213~293 ` f-~

~l .

at 90C prior to mi~ing. To prepare the thermoplastic polyurethane stannous octoate, 0.05-0.10 ~. were added 1-to the polyol samples and mixed. The MDI was then added and the mi~ture rapidly stirred un~il it thickens (18-26 sec) at which point it is then poured into a Teflon*
coated pan and allowed to cure. After curing the elastomer is granulated, dried at 100C and 0.3 mm Hg ~-`
for 14-18 hrs.
The dried polymer is compression molded at 400F. Specimens for tensile, die C and split tear were die cut from the molded plaques after standing 5 days at ~-ambient temperature. An elastomer of 87 Shore A
hardness and 6000 psi tensile strength is obtained.
The dried polymer is extruded in a 3/4" e~truder through a 4" film die at a profile of: zone 1, 206OC;
I zone 2, 212C; zone 3, 212C; die, 215C. The resulting nice clear tape has 300% modulus of 1630 psi and ultimate tensile strength of 5300 psi.
In a similar manner thermoplastic polyurethanes at 35% hard segment levels were made from the other polyol blends resulting in nice, clear e~truded tapes and clear compression molded plaques. The physical property data is summarized in the Table 2.
` :-.
PROPOSED EXAMPLES:

E~amD1e 1. A blend of 50 parts polyol with OH# 112.7 and 50 parts OH# 50.1 gives a polyol with OH# 81.4.

PREPARATION OF A THERMOPLASTIC POLYURETHANE - 35% Hard Segment A 2000 ml resin flask was charged with 950 g. of the polyol blend and vacuum dried polyol. In addition, 1,4-butanediol, 160.0 9., 1.78 mole, and less than 1 wt%

W093/~4549 21~293 PCT/~S93/04785 ~ ~

~';;'" ' of a mi~ture of phenolic antio~idant, ester mold relea~e 1`
and other processing aids were added. The mi~ture was 1'`'',',''!' ' dehydrated at 85C in vacuo, 1-2 mm Hg, for two hours i~-after which time period 300 9. increments were wei~he~ ;
5 out and placed in a 90C oven prior to mi~ing with the ~-isocyanate.

Reaction with Diphenylmethane Diisocyanate Diphenylmethane diisocyanate, MDI, 170.0 9., 0.680 mole, increments were weighed out and maintained ;;~
at 90C prior to mi~ing. To prepare the thermoplastic polyurethane stannous octoate, 0.05-0.10 9. were added ;
to the polyol samples and mi~ed. The MDI was then added and the mi~ture rapidly stirred until it thickens (18-26 sec) at which point it is then poured into a Teflon~
coated pan and allowed to cure. After curing the elastomer is granulated, dried at 100C and 0.3 mm Hg for 14-13 hrs.
The dried polymer is compression molded at ` -400F. Specimens for tensile, die C and split tear were die cut from the molded plaques after standing 5 days at ambient temperature. An elastomer of 85-95 Shore A
hardness and 6000 psi tensile ætrength is obtained. `
The dried polymer is extruded in a 3/4~ e~truder . `
through a 4~ film die at a profile of: zone 1, 1-25 200-210C; zone 2, 205-215C; zone 3, 205-215C; die, ';
205-220C. The resulting nice clear tape has 300%
modulus of 1500-2500 psi and ultimate tensile strength ~';~;
of 5000-6500 psi.

E~am~le II. A blend of 50 parts polyol with OH# 50.1 30 and 50 parts OH~ 27.9 gives a polyol with OH# 39.

WO 93/24549 P~/US93/04785 . ~ ~
21352~3 PREPARATION OF A THERMOPLASTIC POLYURETHANE - 35% Hard~
Segment A 2000 ml resin flask was charged with 550 g. of the polyol blend and vacuum dried polyol. In addition, 5 1,4-butanediol, 147.2 g., 1.63 mole, and less than 1 wt%
of a mi~ture of phenolic antio~idant, ester mold release and other processing aids were added. The mi~ture was dehydrated at 85~C in vacuo, 1-2 mm Hg, for two hours after which time period 300 9. increments were weighed out and placed in a 90C oven prior to mi~ing with the isocyanate.

Reaction with Diphenylmethane Diisocyanate Diphenylmethane diisocyanate, MDI, 137.0 g., 0.548 mole, increments were weighed out and maintained at 90C prior to mi~ing. To prepare the thermoplastic polyurethane stannous octoate, 0.05-0.10 9. were added to the polyol samples and mi~ed. The MDI was then added ~-and the mixture rapidly stirred until it thickens (18-26 sec) at which point it is then poured into Teflon*
coated pan and allowed to cure. After curing the elastomer is granulated, dried at 100C and 0.3 mm Hg for 14-18 hrs.
The dried polymer is compression ~olded at 400F. Specimens for tensile, die C and split tear were die cut from the molded plaques after standing S days at ambient temperature. An elastomer of 80-90 Shore A
hardness and 5000-6000 psi tensile strength is obtained.
The dried polymer is estruded in a 3/4" extruder through a 4" film die at a profile of: zone 1, 30 200-210~C; zone 2, 205-215C; zone 3, 205-215C; die, 205-220C. The resulting nice clear tape has 300% -. W093/24~49 PCT/VS93/0478~ ~
213~2~

I ~
modulus of 1500-2500 psi and ultimate tensile strength~ i, of 5000-6500 psi. 3 SUMMARY OF PHYSICAL PROPERTIES ~;

E~trusion:

5 Polyol 300% Ultimate Ultimate -~
Blend Modulus Tensile(psi) Elong.(~

V 1631 5307 595 :~:

Compression Molded:

Polyol 300%Ultimate Ultimate 15Blend Hardness Modulus Tensile Elong(%) V 87 ~ 1916 6011 677 20 VI 88 A 1863 4696 705 ~, f i ".~.. ~ .. .

Claims

WHAT IS CLAIMED IS:

1. A thermoplastic polyurethane or polyurea elastomer characterized by being made by reacting in a "one-shot" process a polyol blend of polyether polyols comprising a first polyol and a second polyol, a diisocyanate, and a difunctional, isocyanato-reactive chain-extender, the first polyol being prepared utilizing a double metal cyanide complex catalyst and having a molecular weight of between about 1,000 and about 5,000, said first polyol having an end group unsaturation level of no greater than 0.04 milliequivalents per gram of polyol, the second polyol being a polyether polyol having an average molecular weight of between about 1,000 and about 20,000, the second polyol being present in an amount of between about 5% and about 50% based upon the weight of said polyol blend, with the proviso that the average molecular weight of said second polyol is different from the average molecular weight of said first polyol, and with the additional proviso that the polydispersity of said polyol blend is greater than the polydispersity of said first polyol, the polydispersity of said polyol blend being between 1.09 and about 3.0, the equivalent ratio of NCO groups on said diisocyanate to active hydrogen groups on said polyol plus chain extender being between about 1:0.7 and about 1:1.3, and the molar ratio of chain extender to polyol being between about 0.15:1 and about 75:1, said elastomer having a hardness of between a 75 Shore A and about a 75 Shore D.

2. The elastomer of claim 1 characterized in that said chain extender is selected from the group consisting of diols, diamines, and combinations thereof.

3. The elastomer of claim 1 characterized in that said chain extender is selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butane diol, pentane diol, 3-methylpentane-1,5-diol, hexane diol, oxyalkylated hydroquinone, resorcinol and bisphenol A, hydrogenated bisphenol A, 1,4-cyclohexane dimethanol, polyalkylene oxide diols with molecular weights between 100 - 500, diethyltoluene diamine, ethylene diamine, 4,4'-methylene bis(2-chloroaniline) ("MOCA"), hydrazine, substituted aromatic diamines, N,N-bis(2-hydroxypropyl)-aniline, and combinations thereof.

4. The elastomer of claim 1 characterized in that said elastomer additionally contains at least one compounding ingredient selected from the group consisting of anti-oxidants, plasticizers, uv stabilizers, adhesion promoters, fillers and pigments and employed in an amount of between 0 and about 75 weight percent based upon the total weight of the composition.

5. The elastomer of claim 1 characterized in that said first polyol has a molecular weight of between 1,500 and 4,000 and said polyol blend has a polydispersity of between 1.1 and 1.5.

6. The elastomer of claim 1 characterized in that said polyol blend has an average ethylene oxide content of less than 35 weight percent if the average molecular weight of said polyol blend is less than 4,000.

7. A thermoplastic polyurethane or polyurea elastomer characterized by being made by reacting an isocyanate-terminated prepolymer with a difunctional isocyanato-reactive chain-extender, the isocyanate-terminated prepolymer being the reaction product of a polyisocyanate and a polyol blend of polyether polyols comprising a first polyol and a second polyol, the first polyol being prepared utilizing a double metal cyanide complex catalyst and having a molecular weight of between about 1,000 and about 5,000, said first polyol having an end group unsaturation level of no greater than 0.04 milliequivalents per gram of polyol, the second polyol being a polyether polyol having an average molecular weight of between about 1,000 and about 20,000, the second polyol being present in an amount of between about 5% and about 50% based upon the weight of said polyol blend, with the proviso that the average molecular weight of said second polyol is different from the average molecular weight of said first polyol, and with the additional proviso that the polydispersity of said polyol blend is greater than the polydispersity of said first polyol, the polydispersity of said polyol blend being between 1.09 and about 3.0, the equivalent ratio of NCO groups on said diisocyanate to active hydrogen groups on said polyol plus chain extender being between about 1:0.7 and about 1:1.3, and the molar ratio of chain extender to polyol being between about 0.15:1 and about 75:1, said elastomer having a hardness of between a 75 Shore A and about a 75 Shore D.

8. The elastomer of claim 7 characterized in that said chain extender is selected from the group consisting of diols, diamines, and combinations thereof.

9. The elastomer of claim 7 characterized in that said chain extender is selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butane diol, pentane diol, 3-methylpentane-1,5-diol, hexane diol, oxyalkylated hydroquinone, resorcinol and bisphenol A, hydrogenated bisphenol A, 1,4-cyclohexane dimethanol, polyalkylene oxide diols with molecular weights between 100 - 500, diethyltoluene diamine, ethylene diamine, 4,4'-methylene bis(2-chloroaniline) ("MOCA"), hydrazine, substituted aromatic diamines, N,N-bis(2-hydroxypropyl)-aniline, and combinations thereof.

10. The elastomer of claim 7 characterized in that said elastomer additionally contains at least one compounding ingredient selected from the group consisting of anti-oxidants, plasticizers, uv stabilizers, adhesion promoters, fillers and pigments and employed in an amount of between 0 and about 75 weight percent based upon the total weight of the composition.

11. The elastomer of claim 7 characterized in that said first polyol has a molecular weight of between 1,500 and 4,000 and said polyol blend has a polydispersity of between 1.1 and 1.5.

12. The elastomer of claim 7 characterized in that said polyol blend has an average ethylene oxide content of less than 35 weight percent if the average molecular weight of said polyol blend is less than 4,000,

13. A method of fabricating a thermoplastic elastomer characterized by the steps of:
(a) fabricating a polyol blend of polyether polyols comprising a first polyol and a second polyol, the first polyol being prepared utilizing a double metal cyanide complex catalyst and having a molecular weight of between about 1,000 and about 5,000, said first polyol having an end group unsaturation level of no greater than 0.04 milliequivalents per gram of polyol, the second polyol being a polyether polyol having an average molecular weight of between about 1,000 and about 20,000, the second polyol being present in an amount of between about 5% and about 50% based upon the weight of said polyol blend, with the proviso that the average molecular weight of said second polyol is different from the average molecular weight of said first polyol, and with the additional proviso that the polydispersity of said polyol blend is greater than the polydispersity of said first polyol, the polydispersity of said polyol blend being between 1.09 and about 3.0, (b) reacting said polyol blend with a diisocyanate to produce an isocyanate-terminated prepolymer, and (c) reacting said isocyanate-terminated prepolymer with a difunctional isocyanato-reactive chain extender in a mold or in an extruder in order to produce a hard elastomer characterized by a hardness of between a 75 Shore A and about a 75 Shore D, with the proviso that when the molecular weight of the polyol is less than 4,000, then the polyol blend has an ethylene oxide content of less than 35 weight based upon the weight of the polyol.

14. The method of claim 13 characterized in that said chain extender is selected from the group consisting of diols, diamines, and combinations thereof.

15. The method of claim 13 characterized in that said chain extender is selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butane diol, pentane diol, 3-methylpentane-1,5-diol, hexane diol, oxyalkylated hydroquinone, resorcinol and bisphenol A, hydrogenated bisphenol A, 1,4-cyclohexane dimethanol, polyalkylene oxide diols with molecular weights between 100 - 500, diethyltoluene diamine, ethylene diamine, 4,4'-methylene bis(2-chloroaniline) ("MOCA"), hydrazine, substituted aromatic diamines, N,N-bis(2-hydroxypropyl)-aniline, and combinations thereof.

16. The method of claim 13 characterized in that said first polyol has a molecular weight of between 1,500 and 4,000 and said polyol blend has a polydispersity of between 1.1 and 1.5.

17. The method of claim 13 characterized in that said elastomer additionally contains at least one compounding ingredient selected from the group consisting of anti-oxidants, plasticizers, uv stabilizers, adhesion promoters, fillers and pigments.

18. The method of claim 17 characterized in that said compounding ingredient is employed in an amount of between 0 and about 75 weight percent based upon the total weight of the composition.

19. The method of claim 13 characterized in that steps (b) and (c) are conducted simultaneously.

20. The method of claim 13 characterized in that said hardness is between an 80 Shore A and a 65 Shore D.

21. A "one-shot" process for producing a thermoplastic polyurethane or polyurea elastomer which comprises reacting a polyol blend of polyether polyols comprising a first polyol and a second polyol, a diisocyanate, and a difunctional, isocyanato-reactive chain-extender, the first polyol being prepared utilizing a double metal cyanide complex catalyst and having a molecular weight of between about 1,000 and about 5,000, said first polyol having an end group unsaturation level of no greater than 0.04 milliequivalents per gram of polyol, the second polyol being a polyether polyol having an average molecular weight of between about 1,000 and about 20,000, the second polyol being present in an amount of between about 5% and about 50% based upon the weight of said polyol blend, with the proviso that the average molecular weight of said second polyol is different from the average molecular weight of said first polyol, and with the additional proviso that the polydispersity of said polyol blend is greater than the polydispersity of said first polyol, the polydispersity of said polyol blend being between 1.09 and about 3.0, the equivalent ratio of NCO groups on said diisocyanate to active hydrogen groups on said polyol plus chain extender being between about 1:0.7 and about 1:1.3, and the molar ratio of chain extender to polyol being between about 0.15:1 and about 75:1, said elastomer having a hardness of between a 75 Shore A and about a 75 Shore D.