DE2123969A1 - Production of mixed polyesters based on caprolactone - Google Patents

Description

SCHERING AG

Patent department

Λχβη / Bu

Production of mixed polyesters Giipro I act on- Basi s

The subject of the invention is a further development of the process of the main patent (patent application P 21 15 072.1) for the production of mixed polyesters from caprolactones of the general formula

R-CH- (GR ₂ J _4- -C = O-

0

wherein R is a hydrogen atom, a methyl or an ethyl radical can be and where .R is at most three times an alkylrer, π should be, and from dicarboxylic acids and polyols with or without the use of inert solvents, in the first stage the caprolactones with an aliphatic polyol in the presence an inorganic catalyst, namely antimony ^) chloride or antimony (V) fluoride, reacted, then optionally mixed with a small amount of water and the hydroxide-containing ICster compounds formed be reacted with the dicarboxylic acid in the second stage without isolation, the equivalent ratio of polyol: Dicarboxylic acid should be> 1, which is characterized in that instead of the antimony (V) halides, a trialkyloxonium salt, whose alkyl groups contain 1 to 4 carbon atoms and are preferably ethyl groups, is used as a catalyst

A particular Ausführungoform of the inventive method is characterized in that the trialkyloxonium SaI /, J ¹ r.iäthyloxoniiUii hexachloroantimonate (V) is used ^f.

Eu are already mixed polyesters made from caprolactone and polyols ■ and dicarboxylic acids and their preparation described

209847/1163

BAD ORfQfNAL

SCHERING AG

Patent department

Ax / Bu -2-

(German Offenlegungsschriften 1 940 942 and 1 946 430).

In the German Offenlegungsschrift 1 940 942, the Production of liquid polyesters based on ε-caprolactone or 6-hydroxycaproic acid, a dicarboxylic acid or their anhydride, a glycol in an excess of 5 to 20 wt .- $ and a polyol with at least 3 hydroxide groups described in the molecule.

| l The polymerization of these 4 components is carried out in a

Temperature carried out from 220 to 24O ⁰ C in the presence of tetraalkyl titanate as a catalyst and a solvent and / or entrainer, in which the catalyst residues are undesirable in a re-use of the product and must therefore not required catalysis.

In the German Offenlegungsschrift 1 946 430 liquid hydroxyl-containing polyesters described. To produce them, ε-caprolactone is used in the presence of a sulfonic acid group bearing ion exchange resin is hydrolyzed with a large excess of water to give 6-hydroxycaproic acid. \

Then a dicarboxylic acid and a mixture of two different Dialcohols are added in excess of 5 to 20% by weight, with considerable effort (at 230) the added Driven off water and then with the addition of a further catalyst (tetraalkyl titanate) at 250 C die polymerizing esterification made.

For further processing, it must be done in a different apparatus the reaction mixture can be dehydrated and degassed under heating in vacuo.

2 09 847/1163

BAD ORfGfNAL ^

SCHi) RIHG AG

Patent department

Ax / Bu. -3-

To get a product with the properties you want, a polyalcohol with at least 3 OH groups per molecule must also be used during production.

Has opposed both of the above-mentioned disclosure documents the method according to the invention each has several of the following advantages:

1. The lactone used is not hydrolyzed.

2. The use of a single catalyst (trialkyloxonium salt) is sufficient.

3 "The e:" finding method requires lower levels 1 temperatures than the known method.

4. When the final product is filtered, the catalyst and its decomposition products removed.

5. It is not necessary to use a dialcohol geiaiseh.

6ο No additional polyalcohol is required.

7. No excess of dialcohol is required, which must then be removed and / or during the reaction is lost because the temperature is too high.

8. The process according to the invention requires only one reactor for its successive reaction stages and does not require any cleaning or separation processes in between.

According to one that does not belong to the known state of the art Proposal is ε-caprolactone in the presence of an antimony (V) halide or a trialkyloxonium salt as a catalyst by a dialcohol as a ring opening agent

-4- 209847/1163

SCHBRIlTG AG

Patent department

Ax / Bu -4-

polymerized to form an ester bearing OH groups at the chain ends. Following the same suggestion, the Catalyst darfach optionally by a small amount of water to Alitimon (V) oxide - decomposed hydrate, which in a subsequent heat supply, optionally with the supply of a small amount of a mono-, di- or polyalcohol that catalyzes the esterification of the still free carboxyl groups. According to the same proposal, the catalyst and its residues in the usual filtering of the reaction P product completely removed.

In the same way, the catalysts of the invention, Trialkyloxonium salts, use. Their alkyl groups should contain 1 to 4 carbon atoms and preferably be ethyl groups. As anions of these catalyst salts those are possible, the trialkyloxoniuin salts can stabilize, for example tetrafluoroborate, trifluoromethane sulfonate, hexafluoroantimonate (V) - and preferred Hexachloroantimonate (V) ion.

In the implementation of diols or polyols according to the invention with the lactone the polyalcohols become through the chain extension made less volatile, which is of particular value for the subsequent esterification with dicarboxylic acids is. The water added after the lactone polymerization or the water quickly formed by esterification is then destroyed the polymerization catalyst and supplies antimony (V) oxide hydroxate, which acts as an esterification catalyst the further esterification is clearly catalyzed.

The amounts of catalyst preferably used in the lactone polymerization of 0.03-0.06% by weight trialkyloxonium salt (based on the reaction product of finished polyester)

-5-209 847/1 163

BATH ORIGINAL

SCH ^ RIITG AG

• Patent Department

Ax / Bu -5-

may be an effective esterification catalyst after hydrolytic cleavage, which can also be used successfully in ε-oxycaproyl-free polyesters. By using trialkyloxonium salts in this step-by-step "one-pot esterification process", the esterification times can be significantly shortened, the reaction temperatures can be reduced (not above 200 C), the azeotropic removal of the water with an entrainer becomes superfluous, and the 5-20% glycol excesses usually used (above the calculated amount) can be reduced significantly (preferably to 1 % of the calculated amount) or even omitted entirely. The process described here is generally applicable and also gives good results when using aromatic dicarboxylic acids (eg phthalic acid) in addition to aliphatic dicarboxylic acids (eg adipic acid). The polyesters containing hydroxide groups produced by the process according to the invention can be converted into polyurethanes in solution because of their low or no content of catalyst residues. For the reaction of the hydroxide-containing polyesters with isocyanates in the melt, cleaning with bleaching earth may be necessary, ie the polyester is treated with active bleaching earth (approx. 1 - 2 $) in the heat for a few hours and then filtered off.

Lactones to be used according to the invention are unsubstituted or substituted ε-caprolactones of the general formula

R-CH- (CIt ₂ ) 4 -C =

0-

with R - H, CII _V , C ₂ H ₁ -, where a maximum of 3 of the radicals R may be an alkyl group. .

-6-209847 / 1163

SCHu) RIiJG AG

Patent department

Ax / Bu -6-

Examples of such lactones are:

ε-caprolactone,

α-, ß-, γ-, δ- or s-methyl-B-eaprolactone,

Ethyl-ε-caprolactone,

Dimethyl or diethyl B'-caprolactone or

β, β, δ- or ß ^ jö-trimethyl-E-caprolactone.

Examples of Pcüyole to be used according to the invention are

* a) linear or branched diols with "up to 12 carbon atoms, like lthandiol- (l, 2), B - ^.!. aiidiol- (l, 4), hexanediol- (1,6) or trimethyl-hexanediol- (1,6) odc-r

b) linear or branched polyols with at least 3 OH groups per molecule,

such as butanetriol- (1,2,4), trimethylol-propane or Hexanetriol- (1,2,6) or

c) unsubstituted or substituted cycloaliphatic Polyols such as cyclohexanediol or 1,4-bis (hydroxymethyl) cyclohexane.

Examples of dicarboxylic acids to be used according to the invention are

a) linear or branched aliphatic dicarboxylic acids with 2 to 12 carbon atoms, such as oxalic acid, succinic acid, adipic acid, trimethyladipic acid, decanedicarboxylic acid or

b) 1,9- or 1,10-heptadecanedicarboxylic acid or

c) unsubstituted or substituted cycloaliphatic

209847/116 ORIGINAL BATHROOM

SCILiRIHG AG

P at ent division

Axen / Bu _7_

Dicarboxylic acids with a total of "up to 12 carbon atoms, such as cyclohexane-dicarboxylic acid, or

d) aromatic dicarboxylic acids such as phthalic acid or Terephthalic acid.

-8- 209 8 47/1163,

■ « ■ 1 * tv

- ■ -! ■■ ". Ϊ > - tr-S

SCHÜRIUG AG

Patent department

Ax / Bu -8-

Example

Mixed polyester of e-caprolactone / lexanediol-CljöJ / adipic acid in a molar ratio of 6: 9: 8, caprolactone content approx. 26 fo:

551 g Hexandiöl- (1.6) and 342 g of ε-caprolactone at 40 - 50 ⁰ C presented. Then added 0.43 S (corresponding to 0.03 i ° to total polyester) triethyloxonium hexachloroantimonate thereto and stirred for 4 hours, "at 40 - 50 ⁰ C under stirring to react are then added to the destruction of the catalyst approximately 0.5. ml of water are added and the reaction mixture heated to 100 ⁰ C. Then Substituting 584 g of adipic acid and 5.31 g He-xandiol- (l, 6) (1 # Hexandiolmenge used) was added and esterified under nitrogen according to the following scheme:

1 hour from 150-175 ⁰ C for 1 hour of 1'75-200 ⁰ C for 3 hours at 200 ⁰ C.
9 hours at 200 ° C / 15 torr

A crystalline polyester is obtained with the following

Key figures: /

ber.

Hydroxyl number ■ 42.7 39.7

Acid number 0 0.6

-9-209 8 4 7/1 163

Claims (2)

21239S9 SCHERING AG '■ Patent department Axen / Bu ~ 9- Claims Further development of the · process of the main patent (Patent application P 21 15 072.1) for the production of mixed polyesters from caprolactones of the general formula R-CH- (OR ₂ ) ₄ -C = O in which II can be a hydrogen atom, a methyl or an ethyl radical and in which R can be at most three times an alkyl radical, - oll, and from dicarboxylic acids and poly \ oils with or without the use of inert solvents, with the caprolactones in the first stage with a aliphatic polyoil in the presence of an inorganic catalyst, namely antimony (V) ~ chloride or antimony (V) fluoride, then optionally mixed with a small amount of water and the hydroxide-containing ester compounds formed are reacted with the dicarboxylic acid in the second stage without isolation, wherein the polyol: dicarboxylic acid equivalent ratio should be> 1, characterized in that instead of the antimony (V) halides, a trialkyloxonium salt, the alkyl groups of which contain 1 to 4 carbon atoms and are preferably ethyl groups, is used as the catalyst. 2. The method according to claim 1, characterized in that the trialkyloxonium salt triethyloxonium hexachloroantimonate (V) is used. 209847/1163