DE2234507A1 - PROCESS FOR THE PRODUCTION OF POLYURETHANES - Google Patents

Description

fcappe 22952 / Dr, K. / wz - ■

Imperial Chemical Industries London, UK

Process for the production of polyurethanes Friorltttt * 16.7 «71 - Great Britain The invention relates to polyurethane polymers

and in particular to a new method of manufacture of elastomeric polyurethane polymers ^

GeinäJS of the invention is a method vorgesehlagen "for the preparation of elastomeric polyurethane polymers is listed welchee characterized that a _f-ira weaentllchen linear polyhydroxy compound old" Inem molecular weight greater than 800 and a

209885/1198

übersohuß of S-Isooyanatomethyl- ^ S ^ .- trlmethylcyclohexyl isocyanate are reacted together to prepare a Isocyanatab closed prepolymer Vorpolymei "with a low molecular weight diol, or hydroxylamine Dlamin nriacht, and the reaction continues until a solid product obtained ₀

^ Isooyanatoraethyl- ^ SjS-trimethylcycolhexyl-isocyanate is also known as isophorone diisocyanate »The practical one« It is for the sake of this description that the last " Nomenclature used.

With the expression "low molecular weight diol ⁹ 'is meant a compound which contains two aliphatically" or alizjidieoh bound hydroxyl groups and has a molecular weight of at most 250,

Are using the term "polyhydroxy compounds with a molecular weight of more than 800 ⁿ polyester, Polyätherthioäther and polyacetals intentioned, but it is preferred to use a polyester or polyether. These polymers should preferably be linear, but may also be slightly branched. You should also either be liquid or have a melting point of not more than 6O ⁰ C »

Examples of polyethers that can be used are polymers and copolymers of cyclic oxides such as 1,2-alkylene oxide, e.g. ethylene oxide, epiohlorohydrin, 1,2-propylene oxide * 1,2-butylene oxide? and 2-, 5-butylene oxide, oxycyclobutane and substituted!) Oxycyclobutanes and tetrahydrofurans _λ

209885/1 198 "'*

BATH ORIGINAL.

Polyethers should also be mentioned which are produced, for example, by polymerizing an alkylene oxide in the presence of a basic catalyst and water, glycol or a primary / grade «Mixtures of such polyethers can also be used» The preferred polyethers are polypropylene glycol and polytetrahydrofuran ₀

Examples of polyether thiol ethers used are the products of self-condensation of thioglycias, such as, B-. Thiodiglycol or the condensation of thioglycols with glycols.

The polyesters that can be used *

can be prepared by conventional processes from aliphatic dicarboxylic acids and dihydric alcohols. Suitable dicarboxylic acids are e.g. 6. Bernstein ^ Qlutai ^ Adipin »Pimeiln>Kork-> Azelaln« and sebacic acid as well as mixtures thereof. Small amounts of up to about 20 mole percent phthalic> isophthalic and terephthalic acid can also be used «Suitable dihydric alcohols are, for example, ethylene glycol, 1,2-propylene glycol, diethylene glycol, dipropylene glycol, trimethylene glycol, 1,2-, 1,5-i 2 3 = and 1,4-butylene glycol, neopentyl glycol, pentamethylene glycol and hexamethylene glycol and mixtures thereof »Small amounts of polyols that contain more than two hydroxyl groups, such as ζ ο Β» Glycerine, triraethylolpropane or pentaerythritol, can also be used »The acid value of the polyester should be used are less than 6.0 and preferably less than 3 o The preferred polyesters have melting points below 6O ⁰ C and are derived from glycols with two to eight carbon atoms and dicarboxylic acids with four to ten carbons.

209885/1198

22345Ü7

atoms from ₀ Particularly suitable are polyesters having a molecular weight between 1000 and 2500 which, and are derived from such dicarboxylic acids, especially adipic a glycol or Glycolgeirdsch * Polyester »by polymerization of cyclic lactones or mixtures of cyclic lactones such as Z ₀ Bo £ ~ Caprolactone and its alleyl-substituted derivatives are also suitable

Examples of polyacetals that can be used are the reaction products of aldehydes, vie ζ, B = formaldehyde, acetaldehyde and butyraldehyde, with sw® inert alcohols, such as a, B, propylene glycol. Butylene glycol and

The low molecular weight diol, Dlarnin or Hydroxy ~ arain, which is in the second stage of the new 'procedure is used is preferably one which

diieocyanat V to react with diphenylmethane ^ ala sole further neektloneteilnehmer is capable of forming a crystalline polymer having a melting point of at least 150 ⁰ C, preferably Dioie * Particularly useful are Dlole Äthylengiycol, 1,4-Bufcandlol, 1.6 -Hexenediol, 1,4 »bis- (ü-Hy (Sroxyethoxy} -benzene and 1,6-cyclohexanediol,

Di «; © rate stage of the procedure, that is <? Ie dca prepolymers, can b * i a temperature

from 6ü ^c to 1.50 ⁰ C, preferably 90 ° to HO ⁰ C verden verden,

The, broad level, in the case of the prepolyrcer further 2ΟΟ0Π3 / 1198 3 ■

is reacted with low deal molekularan PiQi ,, can at a temperature of 6o ^Q to 220 ⁰ C, preferably carried out 80 ° C to 200 ^Q "ground.

Small amounts of one or more compounds of this type, which polymers against light or against oxydatlve or thermal discoloration or stabilize against oxidative or thermal degradation, such as alky! substituted © ,, phenolic Compounds can be added * If necessary, fillers «and pigments» can also be added the. In order to interfere with the polysation formation reaction of the To keep diisocyanates low, these additives should be used be dry.

not
It is / soldered »that daa pre-Polynes with the low

molecular diol is reacted immediately after the reaction between the polyhydroxy compound and the isphoron isocyanate has been obtained a Vorpolymerstabilisator can be added to the stability further z \ x improve. Typical additives are Chlorwassörsttof-f, CfsrbonsBureohlorlde, such as; B. benzoyl chloride, Lewis acids, such as.s. Boron trifluoride and strong acids, such as ZO, sulfuric acid or strong acid halide, e, such as Z ₀ Β »phosphorus trichlorido

Reaction between the prepolymer low molecular weight DIoL can be in continuous

885/11 S3

SAD

Catfish are run, for example catfish can use the prepolymer and low molecular weight di-oil, which are based on the

corresponding reaction temperature are preheated ^ unheated -

depending on a / mixing chamber, which has a device for mixing the two ReaktlonstellnsLuaer and is designed so that the liquid Gemisah flows on or into another heated receptacle j, such as z, B> on a moving belt, which over a plate runs, which is heated to the required temperature ο After a short time, the mixture solidifies and can be subjected to final heating in the form of a web. If necessary, it can be broken into strips or granules. » before e »is heated. B _n organic and inorganic bases and organometailisoh "compounds that can be added who the low molecular DLOL if necessary together old" the to the solidification rate of the reaction * to increase mixture.

The final upgrade will be preferential «· wisely carried out in the absence of oxygen and moisture, such as ζ ο Bo In a closed container, under a nitrogen dacka or in a vacuum oven->

The ratio of polyhydroxy compound to Isooyanat, welohes used for dio production of the prepolymers should be such that 1.1 to ₁ S O Ißocyanatgruppen and preferably 3 to 6 isocyanate groups for every hydroxyl group present, the proportion of the isocyanate groups in the prepolymers Sindo which i by _t €; the conventional method can also be determined

209885/1198 " ⁷ -

Hydroxy! Groups Biol Q _s $% 1 to 1.1 s 1 * In cases in which there is an excess of isocyanate groups to the hydroxyl groups ° Pro-products are generally insoluble in solvents * but in other cases, the product is soluble in solvents "in solvents insoluble products know in general are rendered soluble" that "at 8IE mechanically durcharbt1- ^ ^et #typischerweise 'at elevated temperatures" Such methods may also aümmimühlen _i, Mi ^{sehs *> n} with crescent-shaped blades, Exfcrufern etc. can be carried out ο

By the erfindungageaäße method he "suspended solid products, whether they are soluble in a solvent or are not thermoplastic uad suitable augmentation for the production of slastctneren Fonügegenetänden by Druokverformung, extrusion, Kalandr & and other commonly ^l methods used sum molding of thermoplastic materials »In order to achieve the radial properties, it is usually preferred to heat the finished molded object to a temperature of up to ISO ⁰ C for up to approx. 24 hours after molding

The solid elastomers that are soluble in organic solvents, as commonly used in the Production of polyurethane products are used, can be resolved by any conventional device, such as. z, B, through roller mills, mixers with half » Flush-mounted blades, etc. Suitable solvents are inert towards isocyanate and hydroxyl groups »

2 0 9 8 8 5/1 '! 9 9 ... ρ

Examples of these are esters, ketones, hydrocarbons, chlorinated hydrocarbons and more polar aprotic solvents. "Examples of such solvents" are ethyl acetate, butyl acetate, 2-ethoxyethyl acetate, aoetone, methyl ethyl ketone, methyl isobutyl ketone, 4-methoxy k- »methylpentene- 2 »on, cyclohexanone, toluene, xylene, dimethylformsmid, Dlraethylaoetarald, tetrahydrofuran

The polyurethane elastomers produced by the arfinduagsgetnäSe process are also used as

flexible coverings for © ine wide range of substrates, such as, for example © knitted, woven, gefliste textiles made of natural, artificial or synthetic materials, Chiasmi, paper, wood, unfortunately, metals, Qlas, plastics, such as a "Bo polyvinyl chloride and Polyurethane materials, e.g. B »flexible and hard Sohäume = You can also glue" when, "are used by amination Blattoiateriallen such" B ₀ for geßtrlekte ,, woven or felted fabric ©, flexible foams made Polviaylchlorid or polyurethanes and Films *

In the above applications, the elastomer, either in solid form or in solution in a solvent or a solution-medium, erratic, soft to the contrary eats inert to the isocyanate groups, without added hardening "- medium be applied, but it will usually with; an organic polyisocyanate mixed and done conventional methods applied to the substrates

j, whereby the coatings obtained on this white are hardened at a suitable temperature, which is

8857 1 13p

BATH ORIGINAL

temperature and 180 ° C., Organic polyisocyanates * which can be used for curing are, for example, aliphatic diisocyanates such as, for example, hexamethylene diisocyanates, aromatic diisocyanates ₉ such as for B tolylene ~ 2; 4 ~ diisocyanate tolylene ^ ö- diisocyanatp Diphenylmethan-4jl ⁵ -diisocyanate 3-Methyldiphenylmethan · ^, 4 "« diisocyanat, m »and p-Phenylenediisocyanate Chlorophenylen-S ^ diiaocyanat,

4,, 4 ^ Diieocyanato «^^^ diraethyldiphenyl ,, Diphenylatherdiisooyajiate and cycloaliphatic diisocyanates ^ like ζ B-

Ifiophorone diisocyanate, dicyclohexylmethane diisocyanate and methylcyclohexyl diisocyanate and mixtures of these diisocyanates.,

It is preferred. Polyisocyanates to use that contain more than two isocyanate groups per molecule. Typical examples of such polyisocyanates are the reaction products from an excess of an organic one Diisocyanates with a trihydric alcohol or a Qejöiach from a dihydric or a trivalent Alcohol and isocyanurates containing isocyanate groups polymers of diisocyanates and polyisocyanates, as well aromatic triisocyanates, for example 2,4,4'-triisocyanate-O " dlpbenyläther and 2,4,6-trilsocyanatotoluene ,, The amount of the polyisocyanate used for curing in desirable catfish between about 8 and 25 weights " Percent, based on the polyurethane elastoiner, but quantities outside of this range may also be used. If diisocyanates or polyisocyanates are used

BATH ORIGINAL

~ ίο -

are used ^ then the curing temperatures should preferably be between room temperature and 100 ^° C. Isocyanate compounds such as _P Bo adducts from polyisocyanates

with phenols, can also be used ^, in in which case curing temperatures between 70 and 180 ° C are necessary ο

The polyurethane elastomers, if they are dissolved in suitable inert solvents, can also be converted into elastomeric threads by conventional wet or dry spinning processes * and preferably after further polyisocyanate has been added. The inert © organic solvent may beisplels = a way as to distance "that one einspinnt in a solvent _s which is miscible with the inert organic solvent but posed no solvent for the polymer or to a stream of hot oases, such as, Bo air" stroke over the threads after spinning

The hardened © lastomer products have sine excellent resistance to heat, washing and solvents ο

The use of isophorone diisocyanate in the manufacture of elastomers results in products * which have a better color stabilization than is the case with elastomers. di® ßus aromatic isocyanates. "

■; '-. ■ & ζ - B- Tolylenendiisjoayanafc, ' ■ jt ^ - 'm ilaa mum Aush ^ kyn ves ^ ende Polyisotiyanat just «f; s aliphatlfKsh: U> fc .. then the Parb'beibehalturigs

209 885/1198 " ^ll

properties of the hardened product are even better -

Another precursor to the use of isophorone diisocyanate in the present process is that, in contrast to other aliphatic diisocyanates, the products in solution are free of the. Disadvantages of unusual theological behavior ^ like s » H- T hi-Äotr op ie s inä ,

by

The invention is further illustrated by the following examples

explains, in which the parts are expressed as percentages by weight

A mixture of 720 parts of polychylene adipate with a HydroKyl value and an acid ratio of 57-3%: wr _e 1. l mg ICOH / g and 350 parts of isophorone diisocyanate is stirred in an off-atmosphere at 100 ° C. after 3 hours the isocyanate content of the product 9.0 % -

500 parts of this Tor-polymera are then portions *? wise 5iu 49 * 2 ropes 1 ^ 4 · But & ndiöl added, where it is raised from 80 to 180 to 200 ⁰ C: For one hour at this temperature, the elastomer obtained is cooled and. dissolved in ethyl acetate, the clear and colorless loaung with a pesticide content of 55 % and a viscosity of 6 _; , 8 pci se at 25 ° C obtained wj.ro ..

a part dieser.- Lbüung »earth 20% (by euf

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BATH ORIGINAL

v "4

the pesticide content of the solution) of a polyisocyanate (prepared as indicated below) is added and the resulting mixture is poured and allowed to harden, so that a film of O ,, 2 mm thick is obtained xv «

The cured film has the following properties:

Tensile strength (kg / cm ² ) 580

Elongation at break in % 450

Permanent fixation {%) , 60

Module (100 %) ₉₀

( $ 300) 197

in methyl-ethyl-ketone soluble an

mi (Jf) _ln ^ ₀₁ Pf 14.5

Lifetime / (et) 96-lCO

The color retention properties of the film are better than a movie that, in a similar way, is made from an elastomer based on tolylene diisocyanate ο If the polyisocyanate used to cure the elastomer is itself eliphatic, for example aas ßiuretpolyisocyanate which by Reaction of hexamethylene diisocyanate with water or isophorone diisocyanate is preferably obtained, then the dye retention properties of the hardened one are Films even bigger ο

Daa polyisocyanate, daa to harden the polyurethane « elastomer solution is used, as described above is obtained as follows ;;

BATH ORIGINAL

1345 parts of a mixture of 80 %. 2.4 = and 20 % 2.6 ~ Tol ^ gndiisocyanat and 487 parts of ethyl acetate are stirred / heated ^{to 76 to 78 0 C under an inert atmosphere} hours added, keeping the temperature "wfaJc maintained at the given range the mixture is further 75 minutes to 76» by cooling or heating, according to need heated 78 ⁰ C and then cooled Dae product has a Isoeyanatwsrt of about 14 JII ₀

Example 2

If ict example 1 the polyisocyanate curing agent is replaced by an equivalent amount of the polyisocyanate; which by reaction of isophorone isocyanate with trimethylolpropane and diethylenglycol »is obtained or because P by reacting trimethylolpropane with hexa » Inethylendlisoeyanat is obtained, then films which have similar physical properties and very good color retention:

Ex iel 3

500 parts of the prepolymer of Example 1 are heated to 130 ⁰ C and stirred with 49.2 parts of 1,4-butanediol., Makes it impossible for the stirring bia the high viscosity. The mixture is then ^{heated to 130 °} C. until an analysis shows that the isocyanate reaction has ended. The elastomer obtained is then dissolved in ethyl acetate, whereby a clear, colorless solution with a solids content of approximately 45% and an solvent content of 350 poise 25 ⁰ C

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BATH ORIGINAL

is obtained.

Dl · P retention properties of films containing by curing this elastomer with the polyisocyanates given in Example 1 are obtained Similar to those of the films of Example 1,

Example 4

300 parts of the prepolymer of Example 1 are heated to 130 ⁰ C and / 4? Parts of 1,4-butanediol was stirred until the viscosity height made stirring impossible The reaction is continued for a further 10 3tunden by heating to IJW ⁰ C. The elastomer obtained is then performed at I80 to 190 ⁰ C by an extruder through "and the extrudate is oetat dissolved in ethyl *, including a solution nüt a solids content of 35% to produce, which has a viscosity of 55 Boise at 25 ⁰ C .

The parabolic idiosyncrasies of films using this elastomer with the In Example 1 specified polyisocyanates have been prepared «are similar to those of the Films from Example L

Example 5 to 12

Prepolymers are produced by reacting the polyesters and polyethers, which are given in Table 1 below, with loophorondiißocyariat for 1 hour at 100 ° C. in a nitrogen mosquito

209865/1 198 "" ¹⁵

The werdenο be prepared in this manner ¥ orpolymere be mixed with the stated Slycolen and 18O to 190 ⁰ C ₅ to an analysis shows that the reaction is praised * world going to end ο It

_s obtained which are soluble in dimethylformamide '.elastische products. They have excellent color holdover "properties, if it is desired * the solvents = beständigk'eit to improve the product * _s especially when the (Hyeolkoffiponenfee _mind's then only a low proportion of reagents used to prepare the Brodukts this can be done by that _s Curing with the polyisocyanates from Example 1 is carried out, with good color retention properties being again excellent in the products obtained «

- 16 209885/1198

as * 5 6 7 7 8 9 10 11

Polyester A 500 500 - - ~ - -

Polyester 3 ■ ~ fjQO · 500. ~

^I-1 lly ester C. - - "■ ~ 500 κ>

ο Volyat & er A - - 500 to

j £ polyether B - "- - 500

S ^: sophcroEidiisoc: / Äna £ 220 110 220 220 220. 220 330 330 ' KHO

Il .i. «T-3ut. Anaiol 67 * 5 33.75 67.5 - 67.5 67.5 112.5 112.5 157.5 co

Polyester A is a polytetrafluoroethylene adipate with a molecular weight of about 109Q

σ Polyester B is a Polyhaxamftthylenadtpet »it with a molecular weight of about 2000

Polyester gel; a polytetramethylene adipate with a molecular weight of approximately 2000

"Roiyäther Λ is sin Polytetrahydrofursn old- a) molecular weight of about 2C00

Polyether Biztin Polypropylene Glycol has a molecular weight of approximately 2000

Claims (1)

Claims _S method for the preparation of elastomeric characterized PoIyurethanpolymeren that one of a substantially linear polyhydroxy compound having a molecular weight of more than 800 and an excess _s reacted with one another "to produce, the prepolymer having a low molecular weight diol or diamine, hydroxyamine _s * mixed and the reaction fortsetatj until a solid product obtained 1st at a isocyanatabgeschlossenes prepolymer, 2, method according to claim 1 "characterized that the polyhydroxy compound having a molecular weight of more than 800 made of polypropylene glycol or polytetrahydrofuran consists" 3, method according to claim 1, characterized in that that the polyhydroxy compound is a polyester with a molecular weight between 1000 and 2500 and is different from one Glycol with 2 to 8 carbon atoms and a dicarboxylic acid with 4 to 10 carbon atoms, 4 ο A method according to any one of claims 1 to J ₉ characterized _s that a low molecular weight diol is used _Ä consisting Sthylenglycol * 1,4-butanediol, Ιί, β-Hexandioli, l _i = 4- bis = - (beta-hydroxyethoxy) benzene and l ^ o hexanediol is selected ο 18th 209885/1198 223A507 5- The method according to any one of claims 1 to 4 _3, characterized in that it is carried out continuously by independently introducing the prepolymer and the low molecular weight diol, which have been preheated to the appropriate reaction temperature, into a heated mixing chamber and the liquid chain device then it is allowed to flow on a moving belt * which runs over a heated plate "whereby the mixture solidifies, β ο Method according to one of Claims © 1 to 5 *, characterized in that, after solidification, the polyurethane is subjected to a final heating ο 7c Method according to Claim 6 _S, characterized in that the final heating is carried out in the absence of oxygen and moisture ο 8. Process according to one of Claims 1 to 7, characterized in that a polyurethane product which is insoluble in solvents is converted into a product which is soluble in solvents by mechanical working through, 9> Method according to claim Q ₃ characterized in that " the mechanical processing is carried out at an elevated temperature" 10. Process for the production of coverings or adhesive layers, characterized in that a polyurethane polymer «, which has been produced by a method according to one of claims 1 to 9, with an organic 209885/1198 -19- see polyisocyanates like, the mixture is applied to a substrate and the mixture cures ^{at a temperature between room temperature and ISO 0 C.} 2 09 885/1 198 BATH ORIGINAL.