DE1268837B - Process for the production of thermally stable linear polyureas - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY GERMAN Wj9 in the PATENT OFFICE

EDITORIAL

Int. Cl .:

Number:
File number:
Registration date:
Display day:

C08g

German class: 39c -6

P 12 68 837.8-44
January 27, 1961
May 22, 1968

It is known, linearly constructed, thermoplastic polyureas with the general grouping

(_ R -NHCONH-)

by reaction of diamines with urea, phosgene, carbonic acid esters, diimidazolylcarbonyl or with To produce carbon dioxide. A number of chain terminators have also been mentioned, such as Monoamines, ζ. B. aniline, monocarboxylic acid halides, diphenylurea, diphenylamine, acetic acid, Hexamethylene diammonium acetate. All polyureas produced by the processes mentioned are but not too technical according to the usual technical processes, such as injection molding, extrusion, etc. flawless, bubble-free molded parts can be processed, because they are obtained under appropriately selected conditions either polycondensation products with low melt and solution viscosity and thus insufficient mechanical resistance to shock loads (notched impact strength), the also in the presence of the stabilizers mentioned when remelting in the form of dried and shredded material for actual shaping within a few minutes, strong bubbles develop show with the formation of mostly foam-like products, or one obtains infusible ones, that is cross-linked, non-deformable and processable products. Such polyureas can be made bubble-free Produce molded parts only with short thermal stress and only in the form of thin foils.

But it is necessary that a thermoplastic material for processing according to the usual Process of extrusion and injection molding the melting with the formation of homogeneous melts Withstands what was done with previous methods without impairing its mechanical properties does not succeed.

As a thermostabilizing chain terminator for polyureas are also already N-Alkoyl- or N-Aroylalkyl, -aryle or -aralkylene di amines have been proposed, but they are expensive.

The claimed process for the production of thermally stable linear polyureas according to per se known method of using diamines and sulfur-free carbonic acid components of chain terminators is characterized in that the thermostabilizing chain terminators are non-volatile Monosulfonic acids can be used. These include: B. to understand such monosulfonic acids, which cannot be distilled without decomposition and cannot be sublimed, such as polynuclear or sub-processes using higher alkyls for the production

of thermostable linear polyureas

Applicant:

Schering Aktiengesellschaft,

1000 Berlin N 65, Müllerstrasse. 170/172

Named as inventor:
Dipl.-Chem. Dr. Rudolf Pasedag,
Dipl.-Chem. Dr. Eugen Griebsch, 4750 Unna

substituted aromatic monosulfonic acids, especially naphthalenesulfonic acids, dodecylbenzenesulfonic acids etc. If appropriate, non-volatile monosulfonic acid derivatives, such as esters and Amides.

In the production of the polyurea from diamines and urea, after the addition of the catalyst, the first phase takes place at 120 to 140 ^° C. Here, monomeric monoureide compounds of the diamines are formed by splitting the urea into isocyanic acid and ammonia and the subsequent reaction of the isocyanic acid with the diamines. Higher temperatures in this stage should be avoided, since otherwise crosslinking will occur in the subsequent condensation stage. The actual polycondensation reaction with the elimination of a second mole of NH ₃ begins at 180 ⁰ C and is completed at 200 to 300 ⁰ C. In the final phase, it is advantageous to apply a vacuum.

This stabilizing effect of the sulfonic acids in question was not foreseeable, as one such stabilization of the polyureas with benzene or toluenesulfonic acids does not take place. she was also surprising because the amidation rate of sulfonic acids is known to be slow. The polyureas stabilized according to the invention have good performance properties and can be Process into threads, foils, extruded and injection-molded goods without bubbles depending on their molecular weight and with Use fluidized bed sintering.

example 1

87.2 g of nonamethylenediamine (amine number 700), 32.6 g of urea and 5.24 g of β- naphthalenesulfonic acid trihydrate (as a stabilizer for the theoretical molecular weight of 10,000) were _{stirred for 4} hours at 122 ° C. under an atmosphere of pure nitrogen. After finishing

809 550/460

10

account the evolution of ammonia was heated 35 minutes at 180 ⁰ C and ₂ hours at 2V 240 ⁰ C, whereby referring again evolution of ammonia began polycondensation. The reaction is continued for 1 hour in a vacuum of 2 mm at 240 ° C. and the melt is quenched. The white Polynonamethylenharnstoff shows in concentrated sulfuric acid (1% solution ^e) a solution viscosity of 1.58 and is tough and strong.

Example 2

Analogously to Example 1, 12.96 g nonamethylenediamine (amine value 691), 4.77 g of urea and 1.25 g / - Naphthalinsulfonsäuretrihydrat polycondensed (for a theoretical molecular weight of 5000) under the following conditions: 1 Hour 122 ° C, 1 hour 180 ⁰ C. , 2 hours 240 ^° C., V ₂ hours 3 mm vacuum / 240 ^° C. The polymer has the solution viscosity η 1% 1.34 and is brittle.

Example3

70.6 g of hexamethylenediamine (amine number 956), 98.2 g of nonamethylenediamine (amine number 691) [molar ratio 1: 1], 72.4 g of urea and 10.48 g of 3-naphthalenesulfonic acid trihydrate (for a molecular weight of 10,000) are converted to 122 for 1 hour ° C, stirred for 1 hour at 18O ⁰ C, 2 hours at 240 ° C and _^3/4 hours at 240 ° C at 1.5 mm of mercury under nitrogen. The colorless, transparent copolymers having good impact resistance and the solution viscosity of 1.54 (l% ig ^e solution in concentrated sulfuric acid).

Claims (1)

Claim: Process for the production of thermally stable, linear polyureas according to known methods Process from diamines and sulfur-free carbonic acid components using chain terminators, characterized in that as a thermostabilizing chain terminator non-volatile monosulfonic acids can be used. Considered publications:
French patent specification No. 1 228 083,
1110 978. 809 550/460 5.68 © Bundesdruckerei Berlin