DE1268840B - Process for the production of polyamides - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

German class:

Number:

File number:

Registration date:

Display day:

C08g

C09d

39 c-10

39 b-22/04
22 h-1/02
1268 840

P 12 68 840.3-44
April 4th 1962
May 22, 1968

It is known that polyamides are made from a diamine of the general formula

H ₂ N- (CHa) ₈ -NH ₂

in which s can assume the value 2 to 12, a bis (aminomethyl) cyclohexane and a dicarboxylic acid. Such compounds are intended for diverse processing in the melt flow. According to an older proposal, which does not belong to the state of the art, 3- (amino-methyl) -3,5,5-trimethyl-cyclohexylamine can be polycondensed with dicarboxylic acids, preferably adipic acid. The corresponding products show very good properties, such as B. enormous surface hardness, a number of interfering properties for the usual purposes. The very high softening point, which makes processing the product very difficult under normal working conditions, should be mentioned in particular.

The invention relates to a process for the production of polyamides by reacting Adipic acid with 3- (amino-methyl) -3,5,5-trimethylcyclohexylamine, which is characterized in that one the S ^ amino-methyO-SjSjS-trimethyl-cyclohexylamine partly by a diamine of the general formula

Process for the production of polyamides

Applicant:

Hibernia chemistry

Company with limited liability,

4660 Gelsenkirchen-Buer

Named as inventor:

Dr. Karl Schmitt,

Dr. Günther Keller f, 4690 Herne;

Dr. Fritz Gude, 4680 Wanne-Eickel

H ₂ N - (CH ₂ ) ,, - NH ₂

(x = 2 to 10)

replaced.

The polyamides obtained in this way show a softening interval which is outstandingly suitable for processing in the melt flow. You can z. B. add hexamethylenediamine in amounts of up to about 50% without losing the glassy character of the condensate. Even with amounts of more than 50%> ^e.g. 80%, clear effects are still obtained, but then again a noticeable increase in the softening point can be observed. It is found here that the more hexamethylenediamine is added in the aforementioned range, the greater the reduction in the softening point. While the non-modified product having a softening range of 220 to 24O ⁰ C, to a polycondensate is obtained in the modified according to the invention the product for example with an addition of 50% hexamethylenediamine with a softening point of 120 to 140 ° C. At the same time shows that, surprisingly, An increase in the surface hardness of the product can be observed due to the addition of hexamethylenediamine. For example, with normal condensates without additives, a ball indentation hardness of 1100 to 1150 kg / cm ^{2 is obtained} , while a product that is modified with 10% hexamethylenediamine easily has a surface hardness of 1250 to 1300 kg / cm ² .

The examples listed in the table below serve to illustrate the invention. The molecular weight of the condensates is given by the reduced specific viscosity of 1% solutions, measured in pure formic acid at 20 ° C (red).

The condensation is carried out under the usual conditions, i. i.e., one can in particular work in such a way that one uses either the starting substances in pure form or in form the salts with adipic acid, both the additive and the cyclic diamine. The in Condensation temperatures generally used are approximately in the range between 150 and 300 ° C. The condensation is here preferably carried out in such a way that the salt mixture Heated under reflux for a few hours above the melting temperature and then after the end a vacuum is applied to this precondensation stage, the temperature possibly being adjusted according to the gradient lets the melt viscosity increase continuously.

809 550/495

Adipic acid

Hexamethylene

diamine

Adipic acid

3- (aminomethyl) -

3,5,5-trimethyl-

cyclohexylamine

Weight percent

Softening interval

Ball indentation hardness

kg / cm ²

Comparative example

example 1 Example 2 Example 3 Example 4

10 30 50 65

100
90
70
50

35

221 to 239

179 to 217

180 to 212
116 to 149
228 to 233

1129
1273
1153
1198
1137

1.72
0.96
1.44
1.41
1.37

Unexpected technical advantages of the polyamides produced according to the invention over those from the USA patent 3,012,994 known polyamides result from the following comparison tests:

Approach A
(inventive method)

0.01 mol salt of adipic acid and hexamethylenediamine,

0.09 moles of adipic acid,

0.09 mol of 3- (amino-methyl) -3,5,5-trimethyl-cyclohexylamine,
10 ml of water.

Approach B
(Method according to US Pat. No. 3,012,994)

0.01 mol salt of adipic acid and hexamethylenediamine,

0.09 moles of adipic acid,

0.09 mol 1,3-bis (amino-methyl) -cyclohexane, 10 ml water.

Both approaches were condensed as follows: 3 hours of refluxing in a common oil bath at 150 to 220 ⁰ C, then increasing the temperature while distilling off the water to 200 to 220 ⁰ C and 4 hours of applying a vacuum of 15 mmHg with an oil bath temperature of 220 to 23O ⁰ C. The polycondensation reactions were carried out under nitrogen.

Properties of the polycondensates

The two polyamides differ significantly in their dissolving behavior in alcohols. To the exam 0.3 g of substance were heated to boiling with the specified solvent in each case.

The following solution behavior was shown:

solvent In the heat
solution Approach A cold stable Approach B Methanol, 1.0 ml In the heat
solution and in the cold stable Not completely dissolved in the heat. At the Ab
cool to room temperature
a stiff, opaque white gel Methanol, 2.0 ml, In the heat
solution and in the cold stable Dissolved in the heat. On cooling down
Room temperature creates a stiff
opaque white gel Methanol, 5.0 ml .... In the heat
solution and in the cold stable Dissolved in the heat. On cooling down
Room temperature creates a stiff,
opaque white gel Ethanol, 1.0 ml In the heat
solution and in the cold stable Dissolved in the heat. On cooling down
Room temperature creates a stiff,
opaque white gel Ethanol, 2.0 ml In the heat
solution and in the cold stable Dissolved in the heat. On cooling down
Room temperature creates a stiff,
opaque white gel Isopropanol, 2.0 ml ... and in the Dissolved only a small part in the heat,
results when cooling down in the room
temperature an opaque slurry

In contrast to the polyamide of batch B, one can also be made from the polyamide of batch A Prepare stable alcoholic solution in the cold. So you can use this substance to produce fuel-soluble paints prepare.

In contrast to the polyamide of approach B, the polyamide of approach A can do an excellent job z. B. in the paint industry, in the painting process as a final coat for artificial leather and for coating Tissues and special papers are used as an alcoholic solution. There is also the option of the alcoholic solutions to produce cast films. Paints of this type can be used as a solution by dipping, Cold and hot spray can be processed. You can also pour or spray out of the container line alcoholic solution.

Claims (1)

5 6 _,, in part by a diamine of common form Claim: Process for the production of polyamides ^H a ^N ~ ( ^CH ^ ~ ^NH a <* = ^{2 to 10} > replaced by reaction of adipic acid with 3- (amino-. methyl) - 3,5,5 - trimethyl - cyclohexylamine, there- 5 characterized by the fact that the documents considered: USA ^ Patent No. 3,012,994. 809 550/495 5.68 © Bundesdruckerei Berlin