DE1282946B - Process for producing homogeneous polyester urethane elastomers - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

DESIGN SCREEN

: -; in £ α .:

German class:

Number:
File number:
Registration date:
Display day:

B65d

39 b5- 22/10

STJnr

1282 946 ■
P 12 82 "946.8-43 '(G 42052)
November 19, 1964 " ..,.,
November 14, 1968 * '

The invention relates to a method for producing homogeneous polyester urethane elastomers from adipic and / or azelaic acid tetramethylene glycol polyesters and polyisocyanates in excess with crosslinking of the NCO-modified polyester with polyfunctional amines, optionally from Solutions.

The industrially produced and used polyester urethanes are mainly linear molecules containing adipate groups. Although these polyurethanes have excellent abrasion resistance, oil resistance and tensile strength and can be prepared such that they practically do not tend to be at temperatures of from - to be 6O ⁰ C or brittle higher, these polyurethanes have at -65 ⁰ C is not an elongation of about 200% · Most have elongations of about 100% or less. If these polyester urethanes are used at relatively low temperatures, they will not withstand the normal impact forces that occur during transport with fuel containers filled with light gasoline or other hydrocarbons. , .- -.

Polyesters are numerous in the art of making polyester urethane elastomers and polyisocyanates have become known, which are active under a wide variety of process conditions Polyfunctional compounds containing hydrogen atoms can be brought to network.

In particular, a method for producing elastomers containing urethane groups (German Auslegeschrift 1152 535) has become known, according to which polyester containing at least two hydroxyl groups are used, those of adipic acid and a glycol mixture of 60 to 75 percent by weight 1,6-hexanediol and 25 to 40 percent by weight 2,3-butanediol. and / or 2,2-dimethylpropanediol-1,3 have been received. The polyesters formed in this way are then reacted with polyisocyanates and the reaction product reacted with peroxides to form elastomers, the low Show tendency to crystallize. Such a product shows after storage for 4 weeks at -5 ° C practically unchanged Shore hardness.

It is also still a process for the production of polyurethane compositions (U.S. Patent 2,953,539) become known, in which a polyester and a polyisocyanate are used in proportions, which correspond approximately to a stoichiometric molar ratio of the two components. The thus obtained Polyurethane is then compounded with carbon black and a peroxide is added to make it crosslinking

Process for producing homogeneous
Polyester urethane elastomers. ■

Applicant:

The Goodyear Tire & Rubber Company,
Akron, Ohio (V. St. A.)

Representative:

Dipl.-Ing. W. Meissner and Dipl.-Ing. H. Tischer, Patent Attorneys, 1000 Berlin 33, Herberiistr. 22nd

Claimed priority:
V. St. v. America November 19, 1963
(324884)

hardened. Such polyurethane compositions are relatively flexible when they are kept at low temperatures for a long time be exposed, but as long as no relatively high elongation is required.

'The invention is now over this ^prior: art, the object zügrunde, a plastic 3NC based vonPolyesterurethanenzuschaffen: which is able to without changing its physical properties unusually low temperature-

■ to withstand temperatures of the order of -65 ° -G ', and at the same time an elongation of at least Should have 100%.

; This task is now according to the invention in characteristic! in a drawing manner in that 1.25 to 2.5 mol an organic, essentially two isocyanate

■ group-containing polyisocyanate with about 1 mol 4P 'of a terminal hydroxyl group Polyester containing at least 20 weight percent tetramethylene glycol azelate with a molecular weight of about 800 to 3000 and about 80 to 0 percent by weight ■ tetramethylene glycol adipate with a molecular weight from about 800 to about 3000, and from about 0.25 to about 0.9 moles of a diamine per mole Polyisocyanate, based on the equivalent of the hydroxyl-terminated polyester is used in excess, are reacted, optionally with removal of the solvent. Any suitable organic polyisocyanate can be used for the process according to the invention,

809 637/1117

such as the following aliphatic diisocyanates: ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, Pentamethylene diisocyanate, oetamethylene diisocyanate, undecamethylene diisocyanate, dodecamethylene diisocyanate, SjS'-diisocyanatodipropyl ether, CyclopentylenrljS-diisocyanate or cyclohexylene-1,4-diisocyanate, or the aromatic diisocyanates such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate or mixtures of 2,4- and 2,6-tolylene diisocyanate, Xylylene -1,4-diisocyanate, xylylene -1,3 -diisocyanate, 4,4 '- diphenylmethane diisocyanate, 2 - nitrodiphenyl-4,4' - diisocyanate, 4,4 '- diphenylpropane diisocyanate, ρ - isocyanatobenzyl isocyanate, m - phenylene diisocyanate, ρ - phenylene diisocyanate, naphthylene -1,4 - diisocyanate or 3,3'-dimethyl-4,4'-diphenylene diisocyanate. However, the aromatic diisocyanates are preferred.

The aromatic diamines used in this invention are used in an amount from about 0.25 to 0.9 moles per mole of organic polyisocyanate, the opposite the equivalent of the polyester is in excess, is used. Preferred results will be obtained when the amount of diamine is about 0.5 to 0.8 mol, based on the excess organic polyisocyanate. Examples of suitable aromatic diamines, using conventional procedures are to be used, the so-called slowly reacting diamines, measured after the boiling point Methylene chloride test, such as methylene-bis-o-chloranüin, o-dichlorobenzidine or 4,4'-bis-aminophenyl sulfone. Examples of suitable rapidly reacting diamines, measured by the boiling methylene chloride test, are 4,4'-methylenedianiline, methyltolidine, tolylenediamine, Duroldiamine, o-toluidine, o-dianisidine. The fast reacting diamines are recommended before use preferably dissolved in a suitable solvent.

The following examples: * If the "invention starts, it does not limit it ** - ·· :, ^: / ·

For example

A prepolymer was prepared by reacting a mixture of 400 parts of tetramethylene glycol azelate with a molecular weight of 2000 and 400 parts of tetramethylene glycol adipate with a molecular weight of 2000 with 169 parts of tolylene diisocyanate. This prepolymer was stored for 28 days in an airtight container, after which it had a content of free NCÖ groups of 4.3 ° / o ^au f ", whereas the theoretical value was 4.2%.

This prepolymer was used to produce sprayable polyurethanes according to the methods described below Approaches given in the table are used.

Prepolymer

Methyl ethyl ketone

2-ethoxyethyl acetate ......

2-nitropropane ..............

10 Vq cellulose acetate butyrate in
2-ethoxyethyl acetate

Spray approach
Prepolymer solution 1
Prepolymer solution 2
SolutionB *. ......

Prepolymer 1 2 solution 200 200 60 60 60 -., - - 60 10 • 10 100 ■. 100 12.8 13, i

* Solution B was made by dissolving 172 parts of methylenebis-δ-chloroaniline produced in 206 parts of methyl ethyl ketone.

Physical properties of the hardened sprayed compositions

Spray approach

Instron Tensile Strength, kg / cm ² , 24 ° C ......

Dimension, mm .. ...... ......

Masland bending test, ⁰ C, OK for tensile strength, kg / cm ^{8 , -53.4 0} C ...........

Elongation,%, -53.4 ° C ........ ■ ,. .......

Volume change,%.

Gehman torsion test ° C. .., /

Tensile Strength, kg / cm

301 343 · "■ 460 490 0.533 0.432. -68 '' -68 497 511 290 . 290 21 20 ' 207-407-44 ° i -307-397-44 below -100 ° C ·. · Below - 100 ° G

89.3

69.6

"Example

A mixture of 700 parts of tetramethylene glycol adipate with a conversion number of 56 and 300 parts of tetramethylene glycol azelate with a conversion number from 59 was heated to 93-104 ° C and 45 minutes under vacuum .; degassed. 178 parts of tolylene diisocyanate were added to the mixture of degassed polyesters added. After a conversion period of 30 meows, a vacuum was applied again.

Stirring under vacuum was continued for 40 minutes continued. The prepolymer produced in this way was filled into metal containers.

From 177 parts of the above prepolymer and 15 parts of molten methylene-bis-o-chloraniün a urethane casting was made. The panels were cured at 93 ° C for 22 hours. The hardened one Elastomer was a homogeneous translucent mass.

1 282 # 46

5: ' ^lYES '«

The physical properties of the hardened are quickly reacting diamines are used,

Elastomers were as follows: is it preferred to use the crosslinker in a solution

Shore A hardness 85 medium or carrier, such as a plasticizer or

₇ '. ,. Extending oil or materials of a similar nature to dissolve.

tensile strength, _ 5 Some suitable plasticizers are tricresyl phosphate,

Kg / cm, Z4 υ jöu tributoxyethyl phosphate and dibutyl phthalate. These

Elongation,%, 24 ° C ... 580 Plasticizers can be used in amounts of about 50 to 60 ° / ₀ tensile strength, of the polyurethane; the rapidly rekg / cm ² , - 53.4 ° C ... 810 acting diamines can be used for the production of casting elongation,%, ¹⁰ pieces with a suitable two-component

-53.4 ° C 366 pressure mixer can be used.

Volume change ' ⁰ L' 23.8 ^{In this} invention, all non-implementation

,,,, “. , ■ ^ ·,, · ^ o ^, capable solvents that are used to produce paints

Masland bending test in order to be used at -62 C, which are sprayed

Tensile strength, _ig, can be used. Examples are benzene,

kg / cm 57 toluene, the paraffinic types of naphtha, the naphtha

Gehman torsional naphtha varieties, the aromatic naphtha

test, ⁰ C - 30 ° / -41 ° / -45 ° / -75 ° C grades, low-boiling chlorinated hydrocarbons,

(no crystallinity) such as methylene chloride, ethyl formate, propyl formate,

2o butyl formate, amyl formate, ethyl acetate, propyl acetate,

EXAMPLE 3 Methyl acetate, butyl acetate, amyl acetate, acetone, Me-From 350 parts of tetramethylene glycol adipate with ethyl ethyl ketone, diethyl ketone, methyl isoamyl ketone, a conversion number of 111, 150 parts of tetra-2-ethoxyethyl propionate, methyl isobutyl ketone, dimethylene glycol conversion number of 59, or an alkane oxyacelate with a low conversion number of 59. Mixtures and 149 parts of a mixed toluene diisocyanate 25 of certain solvents in certain amounts can be used to prepare a prepolymer. The Vorpoly- be expedient if satisfactory Ausbreitungsmerisat (200 parts) was heated to 71 to 77 ⁰ C. Properties and evaporation rates The prepolymer was then to be obtained with a mixture when the polyurethane composition consisting of 28 parts of methylene-bis-o-chloroaniline and 7 parts is sprayed onto a surface. This applies to ins-tetramethylene glycol azelate treated at 104 ° C. After 30 special, if volatile solvents such as benzene were mixed well, the flowable mixture, or acetone, should be used
poured into molds. The cast samples were It is further expedient of spraying mass some 20 hours at 95 ⁰ C treated before the transit pigments and other additives such as surfactants translucent homogeneous plates of physical agents, smoothing agents, for example cellulose acetate butyrate, were reviewed. The results of these 35 or other tests known in the spray coating technique are listed below: add sentences. It is particularly useful

about 0.5 to 5 parts, and preferably about 1 to 2 parts

Add Shore A hardness 91 of a pigment per 100 parts of prepolymer,

Tensile strength to ensure weather resistance and reflective properties

kg / cm ² , 24 ° C 375 40 shafts.

Elongation ° / _0, 24 ° C 400 submicron silica, which phasenhydrolyse by steam Zugfestigkeit'kg / cm ² of silicon tetrachloride in an

—534 C "563 5 hot gaseous atmosphere is produced for

' ₀ '"'"''"''''''the sprayable polyurethane compounds are particularly

Dennung, J _0, -53.4 C ... 280 _e i _{4g gnetj if s} i i _{ner eme} amount of from about 0.1 to

Change in volume, ° / ₀ 17.3 15 parts per 100 parts of solid in the solution

Masland bending test is correct at -57 ° C. The preferred amount is about 0.5

Tensile strength, kg / cm ... 54.5 to about 6 parts, since then the amount of solvent

which are required to achieve a sprayable viscosity

The conversion numbers of the polyesters are as 50 as is not changed significantly. This

The sum of the hydroxyl number and the carboxyl number gives the proportion of pyrogenic silica

given; in general, however, the sprayable composition obtained is also good thixotropic

less than 5 and preferably less than 2. Properties.

With the expression "fast amine crosslinkers" are. With more soluble crosslinkers, the amount of those diamines are meant which when tested in a boiling vehicle or solvent to about 5 to 25% by weight methylene chloride a haze can be reduced within about percent, with a ge-10 generate up to less than 25 seconds. Still films using pressure-mixing equipment This test method will be able to produce a practically cast or cast part. Others saturated Solution of the diisocyanate and the diamine in hand, it is with a very short pot life, d. H. 5 to 20 Se methylene chloride manufactured. This creates habitual and / or erlich in the case of less soluble diamines an approximately 0.2 to 0.5 molar solution of the diisocyanate, 25 to 80 percent by weight or more Cyanate and the diamine, when in methylene chloride, use carriers to allow the reaction mixture to be resolved. The boiling methylene chloride- spread out or as a film or coating on cloth Solutions of the diamine and the polyisocyanate can be sprayed. The amount of carrier or mixed and the length of time measured, the solvent can therefore be used in a suitable manner generation of a turbidity is required. Diamine, which varies from about 5 to over 80 percent by weight after 30 seconds will cause haze to be desired processing properties regarded as slow reacting diamines. to obtain. A preferred proportion of solvent

Claims (3)

ß ^^^^^^ pß ^^ the Ge. mj $ pji .aitfia polyester, 'piarnm. ^ cLjioiyisocyanat, da. this. ^ fengenfereiehy ^ it permitted.,; Spraying / .coatings- * _dürch, "spreading -and to produce foils by spreading .;,.. to. harden at ... elevated / ... temperatures, since the "hardening! Jb ^ LJtain temperature is sufficient; however, in the case of reaction mixtures containing slow reaction hazards, hardening at elevated temperatures may be necessary!" In some cases it has also been found to be expedient and even advantageous to cure conversion mixtures which contain both slowly and rapidly reacting diamines at elevated temperatures of about 40 to 160 ° C. for about 1 to 30 hours. The Masland> bending test: is carried out with a 1.27 * x 7.62-0.0254 to 0.254 cm strip of the cured polyurethane elastomer The strip is bent until both ends are in contact with one another and held together in this position with a clamp. The curved one ne.Streifen is placed in a cold vessel and at a speed of about 5.6 ° G every 6, to. Cooled 8 minutes to the test temperature. The sample is then held at the test temperature for 1 hour, usually at intervals of 5.6 ° G, from -34 ° C to the break point, after which the bent sample is subjected to a rapid blow of 0.346 mkp. The temperature, «at. the ais sample. break! or splintered, is given as the MaslaHd breaking point. ■ * - '":' ~" "■ -. Patent claims Heif" -. ■ 1.; Method for the establishment of homogeneous; Polyesterurethane elastomers made from adipinic and / or azelaic acid tetramethylene glycol polyisocyanates in excess with crosslinking of the NCO-modified polyesters with polyfunctional amines, optionally from solutions, characterized in that 1.25 to 2.5 mol of an organic, in the ¹ essentially two isocyanate group-containing polyisocyanate with about 1 mole of a terminal hydroxyl group-containing polyester which has at least 20 percent by weight of tetramethylene glycol azelate with a molecular weight of about 800 to 3000 and about 80 to 0! percent by weight of tetramethylene glycol adipate with a molecular weight of about 800 to about 3000, and about 0.25 to about 0.9 moles of a diamine per mole of polyisocyanate, which is used in excess with respect to the equivalent of the polyester containing terminal hydroxyl groups, are reacted, optionally with removal of the solvent. 2. The method according to claim 1, characterized in that that a slowly reacting diamine is used as the diamine, which when boiling Methylene chloride test shows turbidity after 25 seconds. 3. The method according to claim 1, characterized in ^ that as a diamine a fast reacting one is used, which in the boiling methylene chloride test a turbidity in less than 25 seconds having. ■ '..... .. Considered publications:
German Auslegeschrift No. 1152 535;
U.S. Patents * Nos. 2,905,652, 2,943,072, 539. ? V KV ^ i ^^ i-it · ^ "snw.;. ■; ■ 5, t- * -ά '' J