EP0833855A1 - Utilisation de diols de polydiene dans des mousses souples en polyurethane - Google Patents

Utilisation de diols de polydiene dans des mousses souples en polyurethane

Info

Publication number
EP0833855A1
EP0833855A1 EP96923917A EP96923917A EP0833855A1 EP 0833855 A1 EP0833855 A1 EP 0833855A1 EP 96923917 A EP96923917 A EP 96923917A EP 96923917 A EP96923917 A EP 96923917A EP 0833855 A1 EP0833855 A1 EP 0833855A1
Authority
EP
European Patent Office
Prior art keywords
polyurethane foam
weight
functionality
diol
parts
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP96923917A
Other languages
German (de)
English (en)
Inventor
Jozef Lucyen Rudolf Cenens
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shell Internationale Research Maatschappij BV
Original Assignee
Shell Internationale Research Maatschappij BV
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shell Internationale Research Maatschappij BV filed Critical Shell Internationale Research Maatschappij BV
Publication of EP0833855A1 publication Critical patent/EP0833855A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00Polymeric products of isocyanates or isothiocyanates
    • C08G18/06Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/67Unsaturated compounds having active hydrogen
    • C08G18/69Polymers of conjugated dienes
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00Polymeric products of isocyanates or isothiocyanates
    • C08G18/06Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40High-molecular-weight compounds
    • C08G18/62Polymers of compounds having carbon-to-carbon double bonds
    • C08G18/6204Polymers of olefins
    • C08G18/6208Hydrogenated polymers of conjugated dienes
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G2110/00Foam properties
    • C08G2110/0008Foam properties flexible
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G2110/00Foam properties
    • C08G2110/0041Foam properties having specified density
    • C08G2110/005< 50kg/m3
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G2110/00Foam properties
    • C08G2110/0041Foam properties having specified density
    • C08G2110/0058≥50 and <150kg/m3
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G2110/00Foam properties
    • C08G2110/0083Foam properties prepared using water as the sole blowing agent

Definitions

  • This invention relates to flexible polyurethane foams containing a polyol, especially polyurethane foams having high resilience.
  • Polyurethane foams having high resilience are typically produced from polyether triols having a number average molecular weight from 4,500 to 6,000 and an isocyanate which provides a narrow range of crosslink density.
  • the polyether triols typically have an average functionality of from 2.4 to 2.7 hydroxyl groups per molecule as a result of unsaturated endgroups that form during manufacture of the triol.
  • Toluene diisocyanate (TDI) , methylene diisocyanate (MDI), TDI/MDI mixtures, and modified TDI or MDI versions are used to produce foams with broad processing latitude.
  • Isocyanate functionality is typically 2.0, and in most cases not higher than 2.3 isocyanate groups per molecule.
  • the polyether triols form resilient foams when combined with the isocyanates having from 2.0 to 2.3 isocyanate groups per molecule under conditions which promote foaming.
  • the present invention is a high resilient polyurethane foam produced from a polydiene diol, preferably a hydrogenated polybutadiene diol, having a number average molecular weight from 1,000 to 20,000, more preferably from 1,000 to 10,000, most preferably from 3,000 to 6,000, and a functionality of from 1.6 to 2, more preferably from 1.8 to 2 hydroxyl groups per molecule.
  • the resiliency of the foam is achieved by the use of the polydiene diol, which is a highly resilient rubber, and by selecting an appropriate amount of a aromatic polyisocyanate having a functionality of from 2.5 to 3.0 isocyanate groups per molecule to assure adequate crosslinking.
  • the polydiene diol foams show superior humid aging properties in comparison to conventional polyurethane foams.
  • the present invention is a resilient polyurethane foam comprising a polydiene diol having a number average molecular weight from 1,000 to 20,000, more preferably from 1,000 to 10,000, most preferably from 3,000 to 6,000, and a functionality of from 1.6 to 2, more preferably from 1.8 to 2, hydroxyl groups per molecule, from 70 to 130, more preferably 90 to 110, index amount of an aromatic polyisocyanate having a functionality of from 2.5 to 3.0 isocyanate groups per molecule, and a blowing agent.
  • the foam shows superior humid aging characteristics in comparison to conventional polyurethane foams.
  • the polydiene diols used in this invention are prepared anionically such as described in United States Patents Nos. 5,376,745, 5,391,663, 5,393,843, 5,405,911, and 5,416,168 which are incorporated by reference herein.
  • the polydiene diols provide stable, resilient foams when the polydiene diol is hydrogenated although unsaturated polydiene diols will also result in polyurethane foams having high resilience.
  • the polydiene diols have from 1.6 to 2, more preferably from 1.8 to 2 terminal hydroxyl groups per molecule and a number average molecular weight between 1,000 and 20,000, more preferably from 1,000 to 10,000, most preferably from 3,000 to 6,000. Hydrogenated polybutadiene diols are preferred and have 1,4-addition between 30% and 70S.
  • Polymerization of the polydiene diols commences - with a monolithium or dilithium initiator which polymerizes a conjugated diene monomer at each lithium site.
  • the conjugated diene is typically 1, 3-butadiene or isoprene since other conjugated dienes cost more and do not provide advantages that justify the expense.
  • the anionic polymerization is done in solution in an organic solvent, typically a hydrocarbon like hexane, cyclohexane or benzene, although polar solvents such as tetrahydrofuran can also be used.
  • the anionic polymerization of butadiene in a hydrocarbon solvent like cyclohexane is typically controlled with structure modifiers such as diethylether or glyme (1,2-diethoxyethane) to obtain the desired amount of 1, -addition.
  • structure modifiers such as diethylether or glyme (1,2-diethoxyethane) to obtain the desired amount of 1, -addition.
  • the optimum balance between low viscosity and high solubility in a hydrogenated polybutadiene polymer occurs at a 60/40 ratio of 1,4-butadiene/l,2-butadiene.
  • This butadiene microstructure is achieved during polymerization at 50°C in cyclohexane containing about 6% by volume of diethylether or about 1000 ppm of glyme.
  • high resiliency is achieved with more than 80% 1,4-addition of isoprene.
  • Anionic polymerization is terminated by addition of a functionalizing agent like those in United States Patents 5,391,637, 5,393,843, and 5,418,296 which are also incorporated by reference, but preferably ethylene oxide, prior to termination.
  • the preferred di-lithium initiator is formed by reaction of two moles of sec-butyllithium with one mole of diisopropylbenzene.
  • This diinitiator is used to polymerize the conjugated diene monomer, preferably butadiene, in a solvent composed of 90%w cyclohexane and 10%w diethylether.
  • the molar ratio of diinitiator to monomer determines the molecular weight of the polymer.
  • the living polymer is then capped with two moles of ethylene oxide and terminated with two moles of methanol to yield the desired polydiene diol.
  • the polydiene diol can also be made using a mono- lithium initiator which contains a hydroxyl group which has been blocked as the silyl ether (as in United States Patents 5,376,745 and 5,416,168 which are also incorporated by reference) .
  • a suitable initiator is hydroxypropyllithium in which the hydroxyl group is blocked as the trimethylsilyl ether.
  • This mono-lithium initiator is used to polymerize the conjugated diene in hydrocarbon or polar solvent. The molar ratio of initiator to monomer determines the molecular weight of the polymer.
  • the living polymer is then capped with one mole of ethylene oxide and terminated with one mole of methanol to yield the mono-hydroxy polydiene polymer.
  • the silyl ether is then removed by acid catalyzed cleavage in the presence of water yielding the desired polydiene diol.
  • the polydiene diols are hydrogenated to improve stability such that at least 90%, preferably at least 95%, of the carbon to carbon double bonds in the diols are saturated. Hydrogenation of these polymers and copolymers may be carried out by a variety of well established processes including hydrogenation in the presence of such catalysts as Raney Nickel, nobel metals such as platinum and the like, soluble transition metal catalysts and titanium catalysts as in U.S. Patent 5,039,755 which is also incorporated by reference.
  • a particularly preferred catalyst is a mixture of nickel 2-ethylhexanoate and triethyl- aluminum.
  • the polybutadiene diols have no less than about 40% 1,2-butadiene addition because, after hydrogenation, the polymer will be a waxy solid at room temperature if it contained less than about 40% 1,2-butadiene addition. To minimize viscosity of the diol, the 1,2- butadiene content should be between about 40 and 60%.
  • the isoprene polymers have no less than 80% 1,4- isoprene addition in order to reduce Tg and viscosity.
  • the diene microstructures are typically determined by C-*- 3 nuclear magnetic resonance (NMR) in chloroform.
  • the polydiene diols have hydroxyl equivalent weights between about 500 and about 10,000, more preferably between 500 and 5,000, most preferably between 1,500 and 3,000. Thus, for the polydiene diols, suitable number average molecular weights will be between 1,000 and 20,000, more preferably between 1,000 and 10,000, most preferably between 3,000 and 6,000.
  • the number average molecular weights referred to here are number average molecular weights measured by gel permeation chromatography (GPC) calibrated with polybutadiene standards having known number average molecular weights.
  • the solvent for the GPC analyses is tetrahydrofuran.
  • the isocyanates used in this invention are aromatic polyisocyanates since they have the desired fast reactivity to make foam.
  • the saturated polydiene diol has a functionality of about 2 hydroxyl groups per molecule, it has been discovered that a polyisocyanate having a functionality of from 2.5 to 3.0 is needed to achieve a crosslink density that results in a stable, high loadbearing and high resilient foam.
  • Using isocyanates of lower functionality results in less stable foams having lower loadbearing capacity and having reduced resiliency. Higher isocyanate functionality will result in foam having a too high closed cell content which will negatively influence the physical properties.
  • An example of a suitable aromatic polyisocyanate which is commercially available is MONDUR MR, from Bayer, a polymeric diphenylmethane polyisocyanate which typically has an isocyanate functionality of 2.7.
  • the polyurethane foams are produced from the polydiene diol, the aromatic polyisocyanate, from 0.5 to 3.5 parts of water, an amine and tin catalyst, and a silicone surfactant.
  • Other ingredients like fire retardants, fillers, etc. may be added by those skilled in the arts of foaming.
  • a variety of amines, tin catalysts, and silicone surfactants for making polyurethane foams are commercially available from Air Products under the tradename DABCO.
  • An example of such a combination useful in making polyurethane foams from polydiene diols is DABCO 33LV amine catalyst, DABCO DC-1 tin catalyst, and DABCO DC-5160 silicone surfactant as described below.
  • the polyurethane foams are preferably prepared by blending all of the components except the isocyanate.
  • the polydiene diol is preferably preheated to reduce viscosity prior to blending. After blending, the aromatic polyisocyanate is quickly added and briefly stirred before pouring the mixture into a mold to hold the expanding foam.
  • the polyurethane foams of the present invention are useful for making articles like seat cushions, carpet backings, gaskets, and air filters.
  • the preferred embodiment of the present invention is a resilient polyurethane foam comprising 100 parts by weight of a hydrogenated polydiene diol having a number average molecular weight from 3,000 to 6,000 and a functionality of from 1.8 to 2.0 hydroxyl groups per molecule, from 0.5 to 3.5 parts by weight of water, from 90 to 110 index amount of an aromatic polyisocyanate having a functionality of from 2.5 to 3.0, preferably 2.7, isocyanate groups per molecule, from 0.1 to 2.0 parts by weight of an amine, from 0.05 to 1.0 parts by weight of a tin catalyst, and from 0 to 2.0 parts by weight of a silicon surfactant.
  • the foam shows superior resiliency and humid aging characteristics in comparison to conventional polyurethane foams.
  • Example 1 shows that polyurethane foams having high resiliency and significantly improved humid aging are produced in accordance with the present invention.
  • the examples are not intended to limit the present invention to specific embodiments although each example may support a separate claim which is asserted to be a patentable invention.
  • Example 1 shows that polyurethane foams having high resiliency and significantly improved humid aging are produced in accordance with the present invention.
  • the examples are not intended to limit the present invention to specific embodiments although each example may support a separate claim which is asserted to be a patentable invention.
  • the hydrogenated polybutadiene diol was heated to 80°C, and 100 parts by weight of the diol were blended with 1 part by weight of water, 0.27 parts by weight of DABCO 33LV amine catalyst, 0.2 parts by weight of DABCO DC-1 tin catalyst, and 0.03 parts by weight of DABCO DC-5160 silicone surfactant.
  • the components were blended for 20 seconds at 2500 rpm.
  • a 100 index amount (22 parts by weight) of MONDUR MR polyisocyanate having a functionality of 2.7 was quickly added and stirring continued for another 15 seconds.
  • a creamy mixture was formed and then poured into a mold sized to hold the resulting polyurethane foam.
  • the polyurethane foam was of good stability, had a regular cellular structure and did not show shrinkage.
  • the density, hardness, rebound resilience, hysteresis, and humid aging hardness loss of the foam was measured according to conventional methods, and also ageing the foam at 90°C and 100% relative humidity for 10 days.
  • the foam properties are reported in Table 1. These data show the excellent ball rebound resilience, the high hardness and the outstanding humid ageing resistance.
  • Example 1 The procedure of Example 1 was used to form a comparison Example by replacing the hydrogenated butadiene diol with a polyether triol having a number average molecular weight of 4,600 and an 80% primary hydroxyl content.
  • the polyurethane foam was stable, had a regular cellular structure and did not shrink during cure.
  • the density, hardness, rebound resilience, hysteresis, and humid aging hardness loss of the foam are reported in Table 1. Compared with Example 1, the foam has for about the same density only half the hardness, a lower ball rebound resilience and loses more than 20% of its original hardness after being humid aged.
  • Comparison Example B Comparison Example B
  • Example 2 The procedure of Example 2 was used to form a comparison Example by repeating all steps except that the polyether polyol was preheated to only 22°C.
  • the polyurethane foam was stable, had a regular cellular structure and did not shrink.
  • the density, hardness, rebound resilience, hysteresis, and humid aging hardness loss of the foam are reported in Table 1. Foaming at a lower temperature increases the density and hardness of the foam. Also in this example the ball rebound resilience is lower than for Example 1, and the hardness loss after humid ageing is substantially higher.
  • the hydrogenated butadiene diol of Example 1 was heated to 80°C and 100 parts by weight of the diol were blended with 2 parts by weight of water, 0.4 parts by weight of DABCO 33LV amine catalyst, 0.3 parts by weight of DABCO DC-1 tin catalyst, and 0.02 parts by weight of DABCO DC-5160 silicone surfactant.
  • the components were blended for 20 seconds at 2500 rpm.
  • a 100 index amount (37 parts by weight) of MONDUR MR polyisocyanate having a functionality of 2.7 was quickly added and stirring continued for another 15 seconds.
  • a creamy mixture was formed and then poured into a mold sized to hold the resulting polyurethane foam.
  • the polyurethane foam was stable, had a regular cellular structure and did not shrink.
  • the density, hardness, rebound resilience, hysteresis, and humid aging hardness loss of the foam was measured according to conventional methods, and also ageing the foam at 90°C and 100% relative humidity for 10 days.
  • the foam properties are reported in Table 2.
  • Example 2 The procedure of Example 2 was used to form a comparison Example by replacing the hydrogenated butadiene diol with a polyether triol having a number average molecular weight of 4,600 and an 80% primary hydroxyl content. The only other variation was that the triol was used at 22°C.
  • the polyurethane foam had a regular cellular structure. The density, hardness, rebound resilience, hysteresis, and humid aging hardness loss of the foam are reported in Table 2. Compared with Example 2, the ball rebound resilience is lower and the humid aged hardness loss is much greater.

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

Abstract

La présente invention se rapporte à des mousses de polyuréthane présentant une grande souplesse et un vieillissement par voie humide amélioré de façon significative. Lesdites mousses sont formées, de préférence, à partir d'un diol de polydiène, de préférence un diol de polybutadiène hydrogéné, comportant une fonctionnalité hydroxyle de 1,6 à 2,0, et à partir d'un polyisocyanate aromatique comportant une fonctionnalité de 2,5 à 3,0. De préférence, le diol de polydiène est mélangé avec des agents moussants avant d'être ajouté au polyisocyanate hautement réactif.
EP96923917A 1995-06-23 1996-06-21 Utilisation de diols de polydiene dans des mousses souples en polyurethane Withdrawn EP0833855A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US494640 1990-03-16
US49464095A 1995-06-23 1995-06-23
PCT/EP1996/002762 WO1997000902A1 (fr) 1995-06-23 1996-06-21 Utilisation de diols de polydiene dans des mousses souples en polyurethane

Publications (1)

Publication Number Publication Date
EP0833855A1 true EP0833855A1 (fr) 1998-04-08

Family

ID=23965333

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96923917A Withdrawn EP0833855A1 (fr) 1995-06-23 1996-06-21 Utilisation de diols de polydiene dans des mousses souples en polyurethane

Country Status (6)

Country Link
EP (1) EP0833855A1 (fr)
JP (1) JPH11509880A (fr)
CN (1) CN1191549A (fr)
BR (1) BR9609350A (fr)
CA (1) CA2224737A1 (fr)
WO (1) WO1997000902A1 (fr)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5710192A (en) * 1996-10-02 1998-01-20 Shell Oil Company Polydiene diols in resilient polyurethane foams
US5874484A (en) * 1997-01-30 1999-02-23 Shell Oil Company Use of polyol mixtures in rigid and semi-rigid polyurethane foams
KR20010012798A (ko) * 1997-05-23 2001-02-26 오노 알버어스 폴리우레탄 포움
WO1998052986A1 (fr) * 1997-05-23 1998-11-26 Shell Internationale Research Maatschappij B.V. Mousses de polyurethane
FR2765227B1 (fr) * 1997-06-25 1999-08-20 Atochem Elf Sa Mousse flexible de polyurethane a base de polydiene hydroxyle
DE102013204991A1 (de) 2013-03-21 2014-09-25 Evonik Industries Ag Herstellung von Polyurethanschäumen, die Polyole auf Polyolefinbasis enthalten
KR101725803B1 (ko) * 2015-04-13 2017-04-11 주식회사 엘지생활건강 탄화수소 폴리올을 이용한 연질 폴리우레탄 폼 및 이를 포함하는 화장품

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4939184A (en) * 1989-03-07 1990-07-03 University Of Akron Polyurethane foam
JP2816563B2 (ja) * 1989-05-15 1998-10-27 株式会社ブリヂストン 飽和炭化水素樹脂骨格ポリウレタンフォームシーリング材
EP0639596A1 (fr) * 1993-08-20 1995-02-22 Bridgestone Corporation Préparation d'une mousse de polyuréthane étanché

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9700902A1 *

Also Published As

Publication number Publication date
JPH11509880A (ja) 1999-08-31
CN1191549A (zh) 1998-08-26
BR9609350A (pt) 1999-05-11
CA2224737A1 (fr) 1997-01-09
WO1997000902A1 (fr) 1997-01-09

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