Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/08—Processes
  • C08G18/10—Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G65/00—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule
  • C08G65/02—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from cyclic ethers by opening of the heterocyclic ring
  • C08G65/32—Polymers modified by chemical after-treatment
  • C08G65/329—Polymers modified by chemical after-treatment with organic compounds
  • C08G65/333—Polymers modified by chemical after-treatment with organic compounds containing nitrogen
  • C08G65/33348—Polymers modified by chemical after-treatment with organic compounds containing nitrogen containing isocyanate group
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/08—Processes
  • C08G18/10—Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
  • C08G18/12—Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step using two or more compounds having active hydrogen in the first polymerisation step
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/40—High-molecular-weight compounds
  • C08G18/48—Polyethers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/40—High-molecular-weight compounds
  • C08G18/48—Polyethers
  • C08G18/4804—Two or more polyethers of different physical or chemical nature
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/40—High-molecular-weight compounds
  • C08G18/48—Polyethers
  • C08G18/4866—Polyethers having a low unsaturation value
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/65—Low-molecular-weight compounds having active hydrogen with high-molecular-weight compounds having active hydrogen
  • C08G18/66—Compounds of groups C08G18/42, C08G18/48, or C08G18/52
  • C08G18/6666—Compounds of group C08G18/48 or C08G18/52
  • C08G18/667—Compounds of group C08G18/48 or C08G18/52 with compounds of group C08G18/32 or polyamines of C08G18/38
  • C08G18/6674—Compounds of group C08G18/48 or C08G18/52 with compounds of group C08G18/32 or polyamines of C08G18/38 with compounds of group C08G18/3203
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G65/00—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule
  • C08G65/02—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from cyclic ethers by opening of the heterocyclic ring
  • C08G65/26—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from cyclic ethers by opening of the heterocyclic ring from cyclic ethers and other compounds
  • C08G65/2642—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from cyclic ethers by opening of the heterocyclic ring from cyclic ethers and other compounds characterised by the catalyst used
  • C08G65/2645—Metals or compounds thereof, e.g. salts
  • C08G65/2663—Metal cyanide catalysts, i.e. DMC's
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L71/00—Compositions of polyethers obtained by reactions forming an ether link in the main chain; Compositions of derivatives of such polymers
  • C08L71/02—Polyalkylene oxides

Definitions

• 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.
• TPU thermoplastic polyurethane
• DMC double metal cyanide
• 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 using 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 products are useful in the preparation of nonionic surface active agents, lubricants and coolants, textile sizes, packaging films, as well as in the preparation of solid or flexible polyurethanes by reaction with polyisocyanates.
• thermoset polyurethane elastomers produced using triols made by DMC catalysis are also known. More specifically, U.S. Patent 4,242,490 discloses the preparation of such elastomers by reacting 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 specified range of molar ratios using either a prepolymer process or a "one-shot" process.
• TPU elastomers Methodology for preparing TPU elastomers is well-established in the art.
• U.S. Patent 4,202,957 discloses polyurethane polyether-based elastomers, made using a select group of polypropylene oxide-polyethylene oxide block copolymers, which this patent states are thermoplastic, recyclable and possess high temperature degradation resistance thus permitting fabrication by injection molding.
• U.S. Patent 5,096,993 discloses the production of TPU elastomers made using DMC-prepared polyether polyols. These elastomers are disclosed in the *993 patent as having excellent physical and chemical properties.
• 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 extruded into shaped articles as might be desired. Accordingly, new methodology for producing hard elastomers having excellent physical and chemical properties made using DMC-prepared polyol(s) in a readily extrudable elastomer-forming composition would be highly desired by the elastomer manufacturing community. The present invention provides such desired methodology.
• the present invention relates to a thermoplastic polyurethane or polyurea elastomer made by reacting in a "one-shot" process (preferably a continuous 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 (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) millieguivalents 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
• the present 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 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
• 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 (preferably 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 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 being between about 0.15:1 and about 75:1, said elastomer
• the present invention relates to a method of fabricating a thermoplastic elastomer which comprises the steps of:
• the polyol blend has an average ethylene oxide ("EO") content as a cap of between about 0% and about 45%, preferably between 5% and 30%, more preferably between 10% and 25%, based upon the total weight of the polyol blend.
• EO average ethylene oxide
• the first polyol and the second polyol are each polyether diols.
• thermoplastic elastomers having a hardness in the range of between a 75 Shore A and a 75 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 complex catalyst. These elastomers exhibit excellent physical and chemical properties.
• the elastomers possess excellent structural strength and stability characteristics.
• the elastomers 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 extrudable elastomers-forming polymers which tend to "slam-up" or crystallize in colder portions of the extruder or die during extrusion processing. Instead of the desired clear, transparent, extruded film one obtains an undesired hazy, milky film that may contain random chunks of hard material.
• 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 prepared by reacting an organic polyisocyanate with a polyalkylene ether polyol(s) in an equivalent ratio of NCO to OH groups of from about 15:1 and about 1.2:1 (preferably between 7:1 and 3:1), using standard procedures, to yield an isocyanate-terminated prepolymer of 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 amines, e.g., tertiary amines and metal compounds such as lead octoates, 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 polyol blends consist essentially of two or three polyols.
• Preferred polyol reactants are the polyether diols and combinations thereof.
• Suitable polyether diols include various polyoxyalkylene diols and combinations thereof, preferably containing ethylene oxide ("EO") 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 hydroxyl content of between about 30 and about 95%, more 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 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 neutralizing with an effective amount of an acid, such as phosphoric acid.
• the polyols can be prepared, according to well-known methods, by condensing an alkylene oxide, or a mixture of alkylene oxides using random or step-wise addition, with a polyhydric initiator or mixture of initiators.
• Illustrative alkylene oxides include ethylene oxide, propylene oxide, butylene oxide, amylene oxide, aralkylene oxides such as styrene oxide, and the halogenated alkylene oxides such as trichlorobutylene oxide and so forth.
• the most preferred alkylene oxide is propylene oxide or a mixture thereof with ethylene oxide using random or step-wise oxyalkylation.
• the polyhydric initiator used in preparing the polyether diol reactant includes the following and mixtures thereof: ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, butane diols, pentane diols, water, combinations thereof, and the like.
• the alkylene oxide-polyhydric initiator condensation reaction is preferably carried out in the presence of a double metal cyanide catalyst.
• unsaturated end groups result in monofunctional 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.
• One double metal cyanide complex catalyst found particularly suitable for use is a zinc hexacyanometallate of formula:
• M may be Co(III), or Cr(III) or Fe(II) or Fe(III); x, y, and z may be fractional numbers, integers, or zero and vary depending on the exact method of preparation of the complex.
• 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 molecular 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 weight and the number-average molecular weight, M /M .
• M /M A M of 1.054 or lower does not allow the formation of a suitable extrusion 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.
• Any suitable organic diisocyanate, or mixture 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 65:35 mixtures 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, xylene diisocyanate (XDI), isophorone diisocyanate (IPDI), 3,3'-bistoluene-4,4'-diisocyanate, hexamethylene diisocyanate (HDI), hydrogenated MDI, hydrogenated XDI, cyclohexane diisocyanate, paraphenylene diisocyanate, mixtures and derivatives thereof, and the like.
• inventions suitably employ an isomeric mixture 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 extenders 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,5-diol, hexane diol, oxyalkylated hydroquinone, resorcinol and b?sphenol A, hydrogenated bisphenol A, 1,4-cyclohexane dimethanol, or polyalkylene oxide diols with molecular weights between 100 - 500, diethyltoluene diamine, ethylene diamine, 4,4'-methylene bis(2-chloroaniline) ("MOCA”), hydrazine, substituted aromatic diamines such as the product commercially available as UNILINK 4200, a product of UOP, Inc., N,N-bis(2-hydroxypropyl)-aniline which is commercially available as ISONOL 100, a product of Dow Chemical Corp.
• the polyether ⁇ olyol(s), polyisocyanate(s) , chain extender(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 extrusion of the formed elastomer as is well-known in the art.
• the prepolymer method or the one-shot method can be used, the one-shot method is preferred.
• the one-shot method is intended to 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 10 percent on an equivalent basis) of polyol prior to carrying out the polyurethane forming reaction.
• urethane forming catalysts can be used as well as the usual compounding ingredients such as antioxidants or other antidegradants. Typical antioxidants include hindered phenols, butylated hydroxytoluene (“BHT”), and the like.
• compounding ingredients include, for example, plasticizers, adhesion promoters, fillers and pigments like clay, silica, fumed silica, carbon black, talc, phthalocyanine blue or green, Ti02, U-V absorbers, MgC03, CaC03 and the like.
• the compounding ingredients, such as fillers are suitably employed in the elastomer in an amount of between 0 and about 75 weight•percent based upon the weight of the elastomer.
• the polymerization reaction may be carried out in a single reaction (one-shot process), or in one or more sequential steps (prepolymer process), using either bulk polymerization or solution polymerization.
• polar solvents such as tetrahydrofuran (“THF”), dimethylformamide (“DMF”), and dimethylacetamide (“DMAC”) are typically utilized.
• THF tetrahydrofuran
• DMF dimethylformamide
• DMAC dimethylacetamide
• all the isocyanate-reactive components are reacted simultaneously with the polyisocyanate.
• 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.
• RIM reaction injection molding
• 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 of both.
• the mixing of the reactants can be carried out at ambient temperature (of the order of 25°C.) and the resulting mixture is then heated to a temperature of the order of about 40°C. to about 130°C, preferably to a temperature of about 90°C. to about 120°C Alternatively, and preferably, one or more of the reactants is preheated to a temperature within the above ranges before the admixing is carried out.
• 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 20°C. to about 115°C.
• 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.
• molecular weight and average molecular weight are intended to designate weight average molecular weight.
• Polydispersity is defined as the weight-average molecular weight divided by the number-average molecular weight.
• 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 (gly e) .
• the reactor was closed, flushed three times with nitrogen and then heated to 100°C. 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 g. was added over a period of 4 hrs at a propylene oxide partial pressure of 30 psi.
• a 2000 ml resin flask was charged with 1100 g., 0.491 moles, of the polyol (OH# 50.1).
• 1,4-butanediol 138.8 g., 1.54 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 85°C in vacuo, 1-2 mm Hg, for two hours after which time period 300 g. increments were weighed out and placed in a 90°C oven prior to mixing with the isocyanate.
• Diphenylmethane diisocyanate, MDI, 125.5 g., 0.502 mole, increments were weighed out and maintained at 90°C prior to mixing.
• MDI diphenylmethane diisocyanate
• 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 420°F. 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 extruded in a 3/4" extruder through a 4" film die at a profile of: zone 1, 195°C; zone 2, 202°C; zone 3, 203°C; die, 209°C.
• the resulting cloudy tape has 300% modulus of 1200 psi and ultimate tensile strength of 4500 psi.
• Diphenylmethane diisocyanate, MDI, 157.9 g., 0.631 mole, increments were weighed out and maintained at 90°C prior to mixing.
• MDI diphenylmethane diisocyanate
• 0.05-0.10 g. were added to the polyol samples and mixed.
• the MDI was then added and the mixture rapidly stirred until it thickens (10-18 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 420-430°F.
• the plaques were hazy and appeared to be inhomogeneous, with areas of clear polymer and areas of white, opaque material.
• the dried polymer is extruded in a 3/4" extruder through a 4" film die at a profile of: zone 1, 190°C; zone 2, 195°C; zone 3, 195°C; 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, 190°C; zone 2, 200°C; zone 3, 200°C; die, 212°C the melt viscosity is too low to allow a film to form.
• 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 (M V ⁇ ) and polydispersity (M /M ) of the polyol blend prior to making the thermoplastic polyurethanes.
• the polydispersity was measured by GPC chromatography, whereas the molecular weight of the blend was calculated based upon the hydroxyl numbers of the individual polyols (polyols A, B, and C) employed in producing the various polyol blends.
• a 2000 ml resin flask was charged with 1100 g. of the polyol blend V and vacuum dried polyol.
• 1,4-butanediol, 173.1 g., 1.92 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 85°C in vacuo, 1-2 mm Hg, for two hours after which time period 300 g. increments were weighed out and placed in a 90°C oven prior to mixing with the isocyanate.
• Diphenylmethane diisocyanate, MDI, 143.0 g., 0.571 mole, increments were weighed out and maintained at 90°C prior to mixing.
• MDI diphenylmethane diisocyanate
• 0.05-0.10 g. were added to the polyol samples and mixed.
• the MDI was then added and the mixture 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 100°C and 0.3 mm Hg for 14-18 hrs.
• the dried polymer is compression molded at 400°F. 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" extruder through a 4" film die at a profile of: zone 1, 206°C; zone 2, 212°C; zone 3, 212°C; die, 215°C.
• the resulting nice clear tape has 300% modulus of 1630 psi and ultimate tensile strength of 5300 psi.
• thermoplastic polyurethanes at 35% hard segment levels were made from the other polyol blends resulting in nice, clear extruded tapes and clear compression molded plaques.
• the physical property data is summarized in the Table 2.
• Example I A blend of 50 parts polyol with OH# 112.7 and 50 parts OH# 50.1 gives a polyol with OH# 81.4.
• a 2000 ml resin flask was charged with 950 g. of the polyol blend and vacuum dried polyol.
• 1,4-butanediol, 160.0 g., 1.78 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 85°C in vacuo, 1-2 mm Hg, for two hours after which time period 300 g. increments were weighed out and placed in a 90°C oven prior to mixing with the isocyanate.
• Diphenylmethane diisocyanate, MDI, 170.0 g., 0.680 mole, increments were weighed out and maintained at 90°C prior to mixing.
• MDI 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 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 100°C and 0.3 mm Hg for 14- ⁇ 8 hrs.
• the dried polymer is compression molded at 400°F. 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 strength is obtained.
• the dried polymer is extruded in a 3/4" extruder through a 4" film die at a profile of: zone 1, 200-210°C; zone 2 , 205-215°C; zone 3, 205-215°C; die, 205-220°C.
• the resulting nice clear tape has 300% modulus of 1500-2500 psi and ultimate tensile strength of 5000-6500 psi.
• Example II A blend of 50 parts polyol witli OH# 50.1 and 50 parts OH# 27.9 gives a polyol with OH# 39. PREPARATION OF A THERMOPLASTIC POLYURETHANE - 35% Hard Segment
• 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 until it thickens (18-26 sec) at which point it is then poured into Teflon*
• the dried polymer is compression molded at 400°F. Specimens for tensile, die C and split tear were
• the resulting nice clear tape has 300% modulus of 1500-2500 psi and ultimate tensile strength of 5000-6500 psi.

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• Chemical & Material Sciences (AREA)
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• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Toxicology (AREA)
• Polyurethanes Or Polyureas (AREA)

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• 1993
  • 1993-05-20 KR KR1019940704403A patent/KR100259667B1/ko not_active Expired - Lifetime
  • 1993-05-20 CA CA002135293A patent/CA2135293A1/en not_active Abandoned
  • 1993-05-20 WO PCT/US1993/004785 patent/WO1993024549A1/en not_active Ceased
  • 1993-05-20 AU AU43841/93A patent/AU4384193A/en not_active Abandoned
  • 1993-05-20 JP JP50062594A patent/JP3326176B2/ja not_active Expired - Fee Related
  • 1993-05-20 EP EP93914018A patent/EP0643733A4/de not_active Withdrawn

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