CN1167494A - Polyurethane composition - Google Patents
Polyurethane composition Download PDFInfo
- Publication number
- CN1167494A CN1167494A CN95196447A CN95196447A CN1167494A CN 1167494 A CN1167494 A CN 1167494A CN 95196447 A CN95196447 A CN 95196447A CN 95196447 A CN95196447 A CN 95196447A CN 1167494 A CN1167494 A CN 1167494A
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- CN
- China
- Prior art keywords
- patent protection
- require
- compound
- prepolymer
- vulcabond
- 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.)
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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
- C08G2110/00—Foam properties
- C08G2110/0041—Foam properties having specified density
- C08G2110/0066—≥ 150kg/m3
-
- 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
- C08G2350/00—Acoustic or vibration damping material
Landscapes
- 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
A method of producing a polyurethane having a density of from 0.3 to 0.7 g/cc and improved physical and dynamic properties comprising preheating a prepolymer consisting of 4,4'-diphenylmethane di-isocyanate and a polymeric polyol having a molecular weight of at least 1000 and mixing said prepolymer with a resin mixture of a polymeric polyol which may be the same as the said polyol.
Description
The present invention relates to use the microvoid polyurethane goods of making engineering parts such as spring assistor (spring assistors), snubber and vibration isolator etc.
Tradition microvoid polyurethane goods are by forming prepolymer or quasi-prepolymer manufacturing from high molecular polyhydroxy component such as polyester or polyethers with naphthalene diisocyanate (NDI) complete reaction or partial reaction.Then, make prepolymer or quasi-prepolymer and water, dibasic alcohol, catalyzer and suitable additive reaction, produce poromerics.This have many shortcomings with using the closely-related method of NDI.Its main drawback is:
The storage period of the prepolymer that polyol and NDI reaction form is limited.
The vapour pressure of NDI is quite high under the normal process temperature, is enough to cause the distribution of toxicity steam.
Producing microvoid polyurethane needs the time in the long mould, and production cost and equipment cost are improved.
The ratio of mixture of prepolymer and chain propagation agent mixture is lower, it is 10: 1 or lower, the viscosity differences of two components is big, and prepolymer instability, these make this material can not use modern more effective processes, for example: high pressure hits stream to be mixed and the low-pressure screw injection moulding machine, wherein liquid mixture can be injected directly in the close die.
In order to overcome these shortcomings, recommend to use 4,4 '-'-diphenylmethane diisocyanate (MDI) replaces NDI.Yet this suggestion is also unsuccessful, because use the hysteresis loss height of the goods of MDI production so far, and physicals and bad dynamic performance.Though try hard to overcome and the relevant problem of use MDI, so far, only obtain limited success.For example noticed following limitation:
Can only be at the molded satisfied product of quality that gets of the low-temperature measurement/proportioning machine of injecting type mixing head with high speed agitator.
Can only be in limited parts by weight scope and density range in the production depanning time be the satisfied moulded parts of time in 5 minutes or the shorter short mould.And change mixing head speed or proportioning machine volume can not address this problem.
Method is moulded in casting method or filling and high pressure hits the moulded parts that stream mixes manufacturing, the compression set poor performance, and the performance under dynamic compressing stress is also poor.
The low high-efficiency method for producing of optimum processing conditions and demould time can not with obtain desirable physical properties and the needed isocyanate groups of dynamic property and equivalence ratio 0.85～1.5 to isocyanate-reactive compound: 1 is compatible.
The consumption of given whipping agent and catalyst consumption, from the goods of can only the mould-forming limited density range of a kind of compound, so, define from given compound can be molded the size and the type of parts.
Usually, spring assistor, cushion plate and the vibroshock of microvoid polyurethane manufacturing has very complicated inside and outside shape, dark groove is usually arranged on endoporus, this just need pour into fluent material or be injected in the mould in 2～5 minutes, before polymerization process was finished, material just reached very high green strength, so that by stretching parts more than 300%, can extract the pore-forming pin out, and not have open-minded splitting.
Spring assistor in automotive suspension is used also needs to have very accurate stress emergent property, this means that the density of material and modulus must be controlled within the very meticulous scope.Adopt common method, have only limited several moulding technologies just can reach this requirement.
Scanning electron microscopy finds, most of above-mentioned shortcomings result from the anisotropy that adopts the microcellular foam that existing tricks of the trade and method produce.Anisotropic experience definition is " global characteristics of the abscess of porous plastics is not good enough ".
The present invention produces in order to overcome above-mentioned shortcoming just.
In other aspects of the present invention, the reacting weight of paying special attention to resin compound is suitable, thereby generation is bordering on ideal isotropy foam structure.
According to the present invention, a kind of method of making microvoid polyurethane is provided, and it comprises: make molecular weight be at least 1000 polymeric polyhydroxy compound, contain glycol or diamines and 4 of 2～20 carbon atoms, 4 '-'-diphenylmethane diisocyanate (MDI) reaction, making density is 0.3～0.7 gram per centimeter
3Urethane.
In a preferred embodiment of the invention, prepolymer or quasi-prepolymer are at least 1000 polymeric polyhydroxy compound from molecular weight, are preferably glycol, triol or tetrol and MDI and form.Then, make the reaction of prepolymer and resin compound, resin compound is by polymeric polyhydroxy compound, and preferably it is with to form the employed polymeric polyhydroxy compound of prepolymer identical and contain the glycol or the diamines formation of 2～20 carbon atoms.Resin compound also can comprise additive such as chain propagation agent, catalyzer, tensio-active agent and whipping agent etc.The equivalent of preferred resin mixture shows with the KOH milligram numerical table of every gram material, is 200～300.
The step that enforcement the present invention produces moulded parts is preferably as follows:
Preheating (i) prepolymer, it comprises vulcabond and polymeric polyhydroxy compound, (ii) resin compound, it comprises polymeric polyhydroxy compound and contains glycol or diamines, chain propagation agent, one or more catalyzer, one or more tensio-active agents, the whipping agent of 2～20 carbon atoms and can be because of technology or commercial other additives of considering needs.
Prepolymer (i) and resin (ii) are metered into mixing device adding to depress.
In described mixing device, adopt the high pressure be enclosed in the high speed agitator of container or be called reaction injection moulding (RIM) technology to hit stream and mix, prepolymer (i) and resin are (ii) mixed.
The liquid mixture of requirement is injected in the close die or open mold of heating with specified proportion.
Described component is reacted in heating mould, until forming firm polymkeric substance, and then after the short period, before the slaking, for example in baking oven before the slaking, the demoulding.
Injecting molded part does not need other aftertreatments except removing to annotate the road defective material.
As what narrated, the polymeric polyhydroxy compound molecular weight is at least 1000, is preferably about 2000.Preferred polymeric polyhydroxy compound is that equivalent is about 110 two functional polyester polyols such as polyhexamethylene adipate, poly-hexanodioic acid butylidene ester and poly-epsilon-caprolactone and polyether polyhydroxy-compound such as poly(propylene oxide) and gathers 1, the 4-butyleneglycol.If need, can use the combination and the multipolymer of more than one polymeric polyhydroxy compound.
Preferred vulcabond used in the present invention is the alkylene diisocyanate that replaces of alkyl or aryl as 4,4 '-'-diphenylmethane diisocyanate (MDI).MDI can be pure or one or more so-called modified version.The molar ratio range of employed vulcabond and polyol is preferably 2: 1 to 5: 1, and more preferably vulcabond is 2.4: 1 to 5: 1 to the ratio of polyol.Isocyanate groups is preferably 0.85: 1 to 1.15: 1 with ratio to isocyanate-reactive compound.
The preferred additives that comprises in reaction mixture comprises one or more catalyzer, is preferably secondary amine or tertiary amine, organometallic compound such as organo-tin compound.By the catalyzer of selecting to suit, can not wait set time from 20 minutes by about 3 minutes in mould.Use same type catalyst, extrudate density can be at 0.35～0.70 gram per centimeter
3Regulate in the scope.Particularly preferred catalyzer comprises amine salt of selling with " Dabco " 33LV by name and the organo-tin compound of selling with " Dabco " F12CL by name.Other additives comprise tensio-active agent, preferred non-silicone surfactants (because using siloxanes can impair the isotropic acquisition of abscess), oxidation inhibitor, bacteriostatic compound and pigment.In example, all umbers or percentage number average are by weight.
Embodiment 1
The quasi-prepolymer that contains 20～22% (weight) isocyanate groups be by equivalent be about 1100 polycaprolactone and 4,4 '-the '-diphenylmethane diisocyanate prepared in reaction.Prepolymer is remained in 42 ℃.
Prepare above-mentioned polyester, 1, the resin compound of 4-butyleneglycol, water, tertiary amine catalyst, organo-metallic tin catalyst and tensio-active agent, and remain in 45 ℃.Make resin compound by prescription, making its equivalent is 270.
Use low pressure and high pressure measurement/mixing machine, make 100 parts of weight quasi-prepolymers and 106 parts of resin compound reactions.Mixture is injected in 60 ℃ of close die, makes elastic element (spring aid) and test plate (panel).
Embodiment 2
Repeat the process of embodiment 1, but the equivalent of polyol (resin) mixture is 230, mixes with 112 parts of prepolymers and 100 parts of polyols (resin) mixture.Make moulded parts as embodiment 1.
Density of material is 250 kilograms/meter
3(can make density by this mixture at an easy rate is 450,550 and 650 kilograms/meter
3Mo(u)lded item, its demould time is lower than 5 minutes).Then, with this moulded parts 90 ℃ of following post curings 12 hours.
Embodiment 3
The quasi-prepolymer that contains 14～16% (weight) isocyanate groups be by equivalent be about 1100 polyether glycol (polytetramethylene ether diol) and 4,4 '-the '-diphenylmethane diisocyanate prepared in reaction.Quasi-prepolymer is remained in 40 ℃.
Prepare above-mentioned polyethers, 1, the resin compound of 4-butyleneglycol, water, tertiary amine catalyst, organo-metallic tin catalyst and tensio-active agent, and remain in 40 ℃.Make resin compound by prescription, making its equivalent is 260.
Use low pressure and high pressure measurement/mixing machine, make 112 parts of weight quasi-prepolymers and 100 parts of polyol mixture reactions.Mixture is injected in 60 ℃ of close die.Make elastic element and test plate (panel).
Density of material is 260 kilograms/meter
3(can make density by this mixture at an easy rate is 450,550 and 650 kilograms/meter
3Mo(u)lded item, its demould time is lower than 5 minutes).Then with this moulded parts 90 ℃ of following post curings 6 hours.
Embodiment 4
The quasi-prepolymer that contains the isocyanate groups of 14～16% (weight) be by equivalent be about poly-hexanodioic acid ethylidene/butylidene ester and 4,4 of 1050 '-the '-diphenylmethane diisocyanate prepared in reaction.Prepolymer is remained in 40 ℃.
The pre-filling moulded above-mentioned line style and branched polyester, 1,4-butyleneglycol, water, tertiary amine catalyst, organo-metallic tin catalyst and surfactant mixtures, and remain in 40 ℃.Make said mixture by prescription, making its equivalent is 240.
Use low pressure and high pressure measurement/mixing machine that 100 parts of weight quasi-prepolymer mixtures and 85 parts of polyol mixture reactions will be injected into from the mixture of this machine in 60 ℃ of close die, make elastic element and test plate (panel).
The foam free of this porous plastics (free foam) density is 230 kilograms/meter
3(can make density by this mixture at an easy rate is 450,550 and 650 kilograms/meter
3Mo(u)lded item, its demould time is lower than 5 minutes).Then with this moulded parts 90 ℃ of following post curings 16 hours.
To at room temperature place for 1 week according to the goods of the foregoing description preparation, measure its physicals then.The result is as shown in the table.
Embodiment1234
Test methodFoam free density kilogram/rice
3250 250 260 230 DIN, 53420 mo(u)lded item density kilogram/rice
35351570 ℃ of 22 hours 50% compression set %, 7 7.5 10.0 9.4 DNI, 53572 screen resilience %, 60 55 50 35 BS 903 of 450 450 450 450 DIN, 53420 hot strength megapascal (MPa)s, 5.5 6.0 4.5 5 DNI, 53571 extension at break %, 450 430 400 400 DIN, 53571 tearing strength Newton/millimeter, 14.4 16 14.0 17.0 DNI
Part AB/B
Dynamic fatigue test
Moulded parts shown in the drawings is carried out dynamic fatigue test, and accompanying drawing is represented the axial cross section of the typical spring assistor (spring assistor) of automobile suspension arrangement.According to each example formulations manufacture component.Component density is about 500 kilograms/meter
3
This test is included in 4,000 newton and loads down with 2 hertz of compression cycle 200,000 times.When test was finished, the parts tension set was no more than 5%, did not all exist any slit split or the vestige of crackle inside and outside the parts.
According to the present invention, use high pressure or low pressure liquid Shooting Technique, casting or other flow molding technology can obtain the microvoid polyurethane goods, particularly automobile suspension arrangement of needed any inside and outside shape.Spring assistor and vibroshock.
Particularly point out, advantage of the present invention is, by adopting any conventional polyurethanes proportioning machine, can be input to liquid mixture and make goods in the close die, therefore, be easy to control the topsoil that vulcabond produces, also can shorten the production cycle, and not have other refining lossess.
In addition, but the parts of the present invention's production weight and profile wide ranges, and its density range can be 0.45～0.70 gram per centimeter
3, and need not to change or regulate processing parameter, also needn't change or the conditioned reaction mixture.
When having these advantages, the physicals of moulded parts and dynamic property also have with MDI makes the level that isocyanic ester had not reached so far.
Claims (15)
1. method of making microvoid polyurethane, it comprises: make molecular weight be at least 1000 polymeric polyhydroxy compound, the glycol that contains 2～20 carbon atoms or diamines and 4,4 '-the '-diphenylmethane diisocyanate reaction, be 0.3～0.7 gram per centimeter to make density
3Urethane.
2. require the method for patent protection in the claim 1, wherein prepolymer is formed by polymeric polyhydroxy compound and vulcabond, and prepolymer and the resin compound that is formed by second kind of polymeric polyhydroxy compound and glycol or diamines are reacted.
3. require the method for patent protection in the claim 2, wherein, second kind of polymeric polyhydroxy compound is identical with first kind of polymeric polyhydroxy compound.
4. require the method for patent protection in claim 2 or the claim 3, wherein, the equivalent of resin compound shows with the milligram numerical table of the KOH of every gram material, is 200～300.
5. claim 2～4 requires the method for patent protection in any one, wherein, in reaction mixture, preferably in resin compound, comprises additive.
6. claim 2～5 requires the method for patent protection in any one, and wherein, prepolymer and resin compound are metered in the mixing device under pressure.
7. require the method for patent protection in the claim 6, wherein adopt the high speed agitator be sealed in the container or high pressure to hit stream and mix.
8. claim 2～7 requires the method for patent protection in any one, wherein blended prepolymer and resin compound is fed in the mould.
9. require the method for patent protection in the claim 8, wherein with mold heated so that form a kind of firm polymkeric substance.
10. require the method for patent protection in the claim 9, wherein the goods of the demoulding are ripened.
11. require the method for patent protection in any aforesaid right requires, wherein employed vulcabond and polyol molar ratio range are 2: 1 to 5: 1, the preferred molar ratio scope is 2.4: 1 to 5: 1.
12. require the method for patent protection in any aforesaid right requires, wherein isocyanate groups is 0.85: 1 to 1.15: 1 with scope to the ratio of isocyanate-reactive compound.
13. require the method for patent protection in any aforesaid right requires, wherein vulcabond is the vulcabond that alkyl or aryl replaces.
14. require the method for patent protection in the claim 13, wherein vulcabond be 4,4 '-'-diphenylmethane diisocyanate.
15. require the method for patent protection in any aforesaid right requires, wherein polymeric polyhydroxy compound is that equivalent is about 110 polyester polyol.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9420107A GB9420107D0 (en) | 1994-10-05 | 1994-10-05 | Polyurethane composition |
| GB9420107.6 | 1994-10-05 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1167494A true CN1167494A (en) | 1997-12-10 |
Family
ID=10762399
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN95196447A Pending CN1167494A (en) | 1994-10-05 | 1995-09-27 | Polyurethane composition |
Country Status (11)
| Country | Link |
|---|---|
| EP (1) | EP0784640A1 (en) |
| JP (1) | JPH10507218A (en) |
| KR (1) | KR970706325A (en) |
| CN (1) | CN1167494A (en) |
| AU (1) | AU3530895A (en) |
| BR (1) | BR9509282A (en) |
| CA (1) | CA2201929A1 (en) |
| CZ (1) | CZ103997A3 (en) |
| GB (1) | GB9420107D0 (en) |
| PL (1) | PL319722A1 (en) |
| WO (1) | WO1996011219A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1326904C (en) * | 2000-12-27 | 2007-07-18 | 日立化成工业株式会社 | Photobase generators, curable compositions prepared by using same and process of curing |
| CN101124257B (en) * | 2005-02-22 | 2010-10-13 | 巴斯福股份公司 | Cylindrical molded bodies based on porous polyurethane elastomers |
| CN101128499B (en) * | 2005-02-22 | 2012-12-19 | 巴斯夫股份有限公司 | Process for producing cylindrical mouldings based on cellular polyurethane elastomers |
| CN102027030B (en) * | 2008-03-14 | 2013-11-27 | 巴斯夫欧洲公司 | Coarse-cell polyurethane elastomers |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4459711B2 (en) * | 2004-05-12 | 2010-04-28 | 日本ポリウレタン工業株式会社 | Rail pad manufacturing method |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1534551A (en) * | 1966-12-06 | 1968-07-26 | Elastomer Ag | Process for obtaining highly elastic, tear-resistant and cold-resistant cellular polyurethane materials having a relatively high specific weight |
| US3856716A (en) * | 1971-03-10 | 1974-12-24 | Laporte Industries Ltd | High density polyurethane foams |
| GB1453794A (en) * | 1974-01-11 | 1976-10-27 | Interox Chemicals Ltd | Polyurethane foams |
| DE2940856A1 (en) * | 1979-10-09 | 1981-04-23 | Elastogran GmbH, 2844 Lemförde | METHOD FOR THE PRODUCTION OF POLYURETHANE ELASTOMERS WHICH MAY CONTAIN CELLS |
| IT1240635B (en) * | 1990-05-04 | 1993-12-17 | Dow Italia | MICROCELLULAR POLYURETHANE POLYMERS PREPARED FROM THREE POLY POLYMERS (TETRAMETHYLENE) GLYCOLS WITH ISOCYANATE GROUPS TERMINALS |
| DE4102174A1 (en) * | 1991-01-25 | 1992-07-30 | Basf Ag | METHOD FOR THE PRODUCTION OF CELLED POLYURETHANE ELASTOMERS USING POLYETHERCARBONATE DIOLES AS THE STARTING COMPONENT |
-
1994
- 1994-10-05 GB GB9420107A patent/GB9420107D0/en active Pending
-
1995
- 1995-09-27 JP JP8512402A patent/JPH10507218A/en active Pending
- 1995-09-27 EP EP95932132A patent/EP0784640A1/en not_active Ceased
- 1995-09-27 AU AU35308/95A patent/AU3530895A/en not_active Abandoned
- 1995-09-27 WO PCT/GB1995/002289 patent/WO1996011219A1/en not_active Application Discontinuation
- 1995-09-27 CA CA002201929A patent/CA2201929A1/en not_active Abandoned
- 1995-09-27 CZ CZ971039A patent/CZ103997A3/en unknown
- 1995-09-27 CN CN95196447A patent/CN1167494A/en active Pending
- 1995-09-27 BR BR9509282A patent/BR9509282A/en not_active Application Discontinuation
- 1995-09-27 PL PL95319722A patent/PL319722A1/en unknown
-
1997
- 1997-04-07 KR KR1019970702259A patent/KR970706325A/en not_active Application Discontinuation
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1326904C (en) * | 2000-12-27 | 2007-07-18 | 日立化成工业株式会社 | Photobase generators, curable compositions prepared by using same and process of curing |
| CN101124257B (en) * | 2005-02-22 | 2010-10-13 | 巴斯福股份公司 | Cylindrical molded bodies based on porous polyurethane elastomers |
| CN101128499B (en) * | 2005-02-22 | 2012-12-19 | 巴斯夫股份有限公司 | Process for producing cylindrical mouldings based on cellular polyurethane elastomers |
| CN102027030B (en) * | 2008-03-14 | 2013-11-27 | 巴斯夫欧洲公司 | Coarse-cell polyurethane elastomers |
Also Published As
| Publication number | Publication date |
|---|---|
| AU3530895A (en) | 1996-05-02 |
| EP0784640A1 (en) | 1997-07-23 |
| PL319722A1 (en) | 1997-08-18 |
| CA2201929A1 (en) | 1996-04-18 |
| JPH10507218A (en) | 1998-07-14 |
| BR9509282A (en) | 1997-11-18 |
| CZ103997A3 (en) | 1997-11-12 |
| GB9420107D0 (en) | 1994-11-16 |
| KR970706325A (en) | 1997-11-03 |
| WO1996011219A1 (en) | 1996-04-18 |
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| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |