DE2145260A1 - TRANSPARENT POLYAMIDE - Google Patents

Description

2U5260

FARBWEKKE HOECHST AKTIENGESELLSCHAFT

formerly Master Lucius & Brüning, Frankfurt / Main

File number: HOE? 1 / T 237

Date: 9.9.1971 Dr. El / rw

Transparent polyamides

Polyamides made from aliphatic diamines and aliphatic dicarboxylic acids have been known for decades. Depending on their composition, these polyamides are either crystalline substances with high melting points or amorphous substances with relatively low freezing temperatures. The crystalline aliphatic Polyamides are used in injection molding. The amorphous alipolitical polyamides can be easily made into foils, tapes, sheets, Process pipes and injection molded parts. However, because of the low glass transition temperatures of the polyamides, they can only be used with use low temperatures, which naturally severely limits their usefulness.

Polyamides made of m-xylylenediamine or mixtures of m-xylylenediamine and p-xylylenediamine with dicarboxylic acids have been used in a number of Patent specifications described. The polyamides described are in many cases crystalline and can be processed into threads. Amorphous, transparent polyamides can be produced from m-xylylenediamine with pimelic acid or azelaic acid. Serve polyamides but have the disadvantage that their freezing temperatures are generally below 100 C; Moldings made from these polyamides can therefore cannot be used at higher temperatures.

It is also known that m-xylylenediarnine with isophthalic acid with Mixtures of isophthalic acid and terephthalic acid transparent Forms polyamides (U3-PS 2.766.222). These polyamides only have one low impact strength which opens up their use in many areas.

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There has now been a method of making transparent polyamides by. Polycondensation of diarains and dicarboxylic acids or their Acid halides, esters, nitriles or amides are known per se Found V / else and under customary conditions, which is characterized in that one

a) m-xylylenediamine or mixtures of p-xylylenediamine and at least 50 mol%, preferably at least 65 mol; £ m-xylylenediamine, and

b) Mixtures of at least one aromatic, 7 to 20 C-

^ Atoms, preferably Ö to 14 carbon atoms, containing dicarboxylic acid, especially mononuclear, in meta- or para-position Carboxyl group-bearing dicarboxylic acid, and at least one aliphatic saturated 5 to 20 carbon atoms, preferably 6 to 12 carbon atoms, containing dicarboxylic acid, the proportion of aliphatic dicarboxylic acid or dicarboxylic acids 10 to 90 mol? a, preferably j> 0 to 70 mol> 0, or mixtures of the corresponding Dicarboxylic acid derivatives

begins.

Necessary for the preparation of the polyamides according to the invention diamines, m-xylylenediamine and p-xylylenediamine can be obtained by hydrogenation of isophthalonitrile or terephthalonitrile ψ.

As aromatic dicarboxylic acids, which together with aliphatic Dicarboxylic acids with m-xylylenediamine or mixtures of at least 50 mol%, preferably at least 6 ^> Mol / a, m-xylylenediamine and p-xylylenediamine are reacted, those with 7 to 20 are suitable C atoms, preferably O to 1 ^ C atoms, or mixtures of these Dicarboxylic acids. Mononuclear dicarboxylic acids bearing carboxyl groups in the meta or para position are particularly suitable Isophthalic acid, Tei-ephthaloriure or Mir, 'hungen au ;; Isophthalic acid and terephthalic acid.

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Further advantageous examples of aromatic dicarboxylic acids to be used according to the invention are 2,5-pyridinedicarboxylic acid, k, k'-diphenyldicarboxylic acid, 1, ^ f-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, k, h '-diphenylsulfondicarboxylic acid.

It is also possible to use mixtures of the aromatic dicarboxylic acids, in particular mixtures of h, k '-diphenylsulfonic acid and isophthalic acid.

As aliphatic dicarboxylic acids, which together with aromatic dicarboxylic acids with m-xylylenediamine or mixtures of m-xylylenediamine and p-xylylenediamine are reacted, such are suitable with 5 to 20 carbon atoms, preferably 6 to 12 carbon atoms, especially adipic acid. Further advantageous examples of the invention The aliphatic dicarboxylic acids to be used are 2-methylglutaric acid, Pimelic acid, suberic acid, azelaic acid, sebacic acid or 1,10-decanedicarboxylic acid.

Mixtures of the aliphatic dicarboxylic acids can also be used will.

The polyamides according to the invention are produced according to known, Process developed for the preparation of polyhexamethylene adipamide. Diamines and dicarboxylic acids are used, if appropriate with the addition of water and / or acetic acid, placed in a stainless steel autoclave. It is sometimes useful to do so beforehand to produce the salts from the diamines and dicarboxylic acids. The components are heated to around 200 to 250 ° C. while stirring. Then the water vapor is released and the temperature is increased to around 26o to 300 ° C. At this temperature it will be about JO minutes stirred in a stream of nitrogen. Eventually evacuation and all that condenses for a long time until the folyamide has the desired molecular weight has reached.

It is often advantageous to have an excess of up to 5 percent by weight, preferably 0.5 to 2 percent by weight, of m-xylylejidiamine or dc-s ucmischec from m-xylylenedia; rir; and to use p-Xylylendiamiη, uil losses by distilling off xylyl '; ndi .-: .. ii'neri at der ί * ό.1 yl.ondenratiun o> n "2» J cjteicSe ^

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2U5260

The polyamides can also be made from m-xylylenediamine or a mixture from m-xylylenediamine and p-xylylenediamine and dicarboxylic acid halides, esters, nitriles or amides by known processes.

Polyamides with particularly high molecular weights and good mechanical properties Properties are obtained if the polyamides produced in the stirred autoclave are preferably used in a further process step condensed in a twin screw extruder under vacuum.

The polyamides according to the invention of the general formula

--pHN-R -NH-CO-E -Col · - R., wherein

R ^ for a m-xylylene radical, which is 0 to 50 mol%, preferably 0 to 35 mol% is replaced by a p-xylylene radical,

R for two or more divalent aromatic, randomly distributed over the macromolecule, containing 5 to 18 carbon atoms, preferably 6 to 12 carbon atoms, in particular mononuclear, bonded in the meta or para position, and aliphatically saturated ones, 3 Hydrocarbon radicals containing up to 18 carbon atoms, preferably k to 10 carbon atoms, the proportion of aliphatic radicals being 10 to 90 mol%, preferably 30 to? 0 mol%,

R for H or OC-R-COOH and

R. for OH or NH-R.-NH, and where χ indicates the degree of polymerization, the reduced specific viscosity of the 1 / o solution in phenol / tetrachloroethane (in a weight ratio of 60: ZfO) at 25 ° C as a measure 1.0 ^u to 2.5 dl / g, preferably 1.5 to 2.0 dl / g,

are characterized by high transparency, good impact strength and good dielectric properties and are excellent for processing by injection molding. They have freezing temperatures of generally over 100 ° C and can be calibrated

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process well after the injection molding process. They are suitable for Manufacture of injection molded articles that can also be used in the range of higher temperatures. Some of the invention Polyamides, especially those containing p-xylylenediamine in Containing coordination with terephthalic acid, if tempered for a sufficiently long period of time at temperatures above the freezing temperature crystallize and are then opaque. However, these polyamides can also be made into transparent moldings by injection molding are processed.

Polyamides of the formula given above are particularly suitable, where R_ for a mixture of statistically about that Macromolecule distributed p-C ^ H.- or / and m-CVH.- and - (CHp) .- best stands.

Moldings made from the polyamides according to the invention are transparent and have good dielectric properties. Because of the high The moldings are freezing temperatures even at relatively high temperatures without any loss of their good mechanical properties to use.

The polyamides according to the invention can be used wherever where transparency and good mechanical properties at higher temperatures are important. You can e.g. B. to foils, plates, Pipes, cable covers and, particularly advantageously, can be processed into technical parts by injection molding.

Examples

The viscosity measurements were carried out on solutions of 1 g of polyamide in 100 ml of phenol-tetrachloroethane (in the weight ratio ÖOr'fO). The freezing temperatures were determined by differential thermoi
it's correct.

100 ml phenol tetrachloroethane (in a weight ratio of 60: ^z f0) at 25 ° C

D thermal analysis at a heating rate of * f ° C / min. loading

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- 6 Example 1

831 g terephthalic acid, 735 g adipic acid, 1380 g m-xylylenediamine and 300 ml of water were placed in a stainless steel autoclave

given. After removing the oxygen in the air with nitrogen Melted in a closed autoclave and stirred at 220 ° C. for 1 hour. Then over the course of 1 hour, the overpressure was on Atmospheric pressure lowered and the temperature at the same time to 275 C - At this temperature was 30 minutes in a stream of nitrogen touched. Then the pressure was reduced to 0.3 mm Hg. The melt was obtained for 30 minutes at these temperature and pressure conditions stirs. A transparent polyamide was obtained with a reduced specific viscosity of 1.9 dl / g. The freezing temperature of the product was II3 C.

The material was made into plates on an injection molding machine 60 χ 60 χ 2 mm in size. The screw temperature was 295 C and the mold temperature 60 C.

The impact strength of the panels was tested by means of a drop test. The panels were exposed to impact stress in such a way that a falling body from different heights was dropped perpendicularly onto the panels stretched out on a frame. The tip of the drop hammer represented a hemisphere with a ψ radius of 10 mm; the weight of the drop hammer was 1 kg. 10 panels were tested per height. At a fall height of 75 cm, the impact energy was sufficient to break 20% of the panels.

Comparative example from example 1

From 831 g isophthalic acid, 83I g terephthalic acid, 1380 g m-xylylenediamine and 3 ^ 0 ml of water was made according to the procedure described above made of a polyamide. The polyamide obtained had a reduced specific viscosity of 2.2 dl / g.

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The material was processed and tested as described above. Even at a drop height of 25 cm, the impact energy was sufficient to break 20% of the panels.

Example 2

From 831 g isophthalic acid, 735 g adipic acid, 1380 g m-xylylenediamine and 300 ml of water was made according to that described in Examplei Method produced a polyamide. The product obtained had a reduced specific viscosity of 1.81 dl / g. The freezing temperature of the transparent polyamide was 120 C.

Example 3

From 831 g of terephthalic acid, 735 g of adipic acid, 966 g of m-xylylenediamine, k 1 * fg of p-xylylenediamine and 3 ^ 0 ml of water, a polyamide was prepared by the method described in Example 1. The opaque polyamide obtained had a reduced specific viscosity of 2.3 dl / g. The glass transition temperature of the product was 123 ° C. The opaque polyamide was injection-molded on an injection molding machine to form transparent plates measuring bO 60 χ 2 mm. The screw temperature was 295 C and the mold temperature 60 C.

example H

A polyamide was produced from 831 g of isophthalic acid, 735 g of adipic acid, 966 g of m-xylylenediamine, * f1't g of p-xylylenediamine and 300 ml of water by the method described in Example 1. The transparent polyamide obtained had a reduced specific viscosity of 2.33 dl / g · ^^ ^e ^ infrared temperature was

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Example 5

A polyamide was prepared from 1162 g of isophthalic acid, 58 g of adipic acid, 966 g of m-xylylenediamine, kik g of p-xylylenediamine and 300 ml of water by the method described in Example 1. The transparent product obtained had a reduced specific viscosity of 2.1 dl / g. The freezing temperature was 142 C-

Example 6

498 g of terephthalic acid, 1219 g of suberic acid, 1375 g of m-xylylenediamine and a polyamide 3OO ml of water was prepared according to the procedure described in Example 1 W method. The transparent product obtained had a reduced specific viscosity of 1.93 dl / g. The freezing temperature of the polyamide was 13 ^ C.

Example 7

From 831 g terephthalic acid, 9 ^ 1 g azelaic acid, 976 g m-Xy.lylenediamine, ^ 18 g of p-xylylenediamine and 300 ml of water were made according to the example 1, a polyamide is produced using the method described. The transparent polyamide obtained had a reduced specific viscosity of 2.3 dl / g and a freezing temperature of 108 ° C.

Example 8

From 831 g of terephthalic acid, 1011 g of sebacic acid, 976 g of m-xylylenediamine, p-xylylenediamine k 18 g and 300 ml water was prepared a polyamide by the method described in Example 1. The transparent polyamide obtained had a reduced specific viscosity of 2.38 dl / g. The freezing temperature of the product was 106 ° C.

Example 9

From 919 g ^, '+' - Diphenylsulfondicarbon.v.Äure, 1023 g adipic acid, 1375 g of m-X, ylyltndiamine and 3CO ml of water was according to the example 1, a polyamide is produced using the method described. The

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holding transparent polyamide had a reduced specific Viscosity of 1.68 dl / g. The freezing temperature of the product was 102 ° C.

Example 10

From 613 g ^, M-diphenylsulfondicarboxylic acid, II69 g adipic acid, 976 g of m-xylylenediamine, * ti8 g of p-xylylenediamine and 300 ml of water a polyamide was produced according to the method described in Example 1. The obtained transparent polyamide had a reduced specific viscosity of 1.87 dl / g. The freezing temperature of the product was 103 C.

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Claims (3)

2U5260 " Patent applications . 1. Process for the production of transparent polyamides by polycondensation of diamines and dicarboxylic acids or their acid halides, esters, nitriles or amides are known per se Manner and under usual conditions, characterized in that one a) m-xylylenediarain or mixtures of p-xylylenediarain and at least 50 mol%, preferably at least 65 mol%, m-xylylenediamine and b) mixtures containing dicarboxylic acid, in particular of at least one mononuclear aromatic, 7 to 20 C W, atoms, preferably 8 to Ik carbon atoms, in the meta- or para-position carboxyl group-carrying dicarboxylic acid, and at least one aliphatic saturated, 5 to 20 Dicarboxylic acid containing carbon atoms, preferably 6 to 12 carbon atoms, the proportion of the aliphatic dicarboxylic acid or dicarboxylic acids being 10 to 90 mol%, preferably 30 to 70 % , or mixtures of the corresponding dicarboxylic acid derivatives begins. 2. The method according to claim 1, characterized in that; i one as aromatic dicarboxylic acid terephthalic acid or isophthalic acid or a mixture of terephthalic acid and isophthalic acid is used. 3. The method according to claim 1, characterized in that the aromatic dicarboxylic acid used is ^ t -, '+ ¹ -Dinhenylsulfondicarbonrräure or mixtures of * t, 4 * -Diphenylsulfondicarbonsäure and isophthalic acid. k. Polyamides of the general formula R ₇ - £ hN-R ₁ -NH-CO-R ₂ -Co3 ~ _x H _{i +} , where ^BAD ORIGINAL - 1 1 - 309818/0937 21452RH R _{1 stands} for a m-xylylene radical which has been replaced by a p-xylylene radical in an amount of from 0 to 50 mol / £, preferably from 0 to 35 mol%, Rp for two or more divalent aromatic, randomly distributed over the macromolecule, containing 5 to 18 C atoms, preferably 6 to 12 C atoms, in particular mononuclear ones, bonded in the meta or para position, and aliphatic saturated ones, 3 to 18 Hydrocarbon radicals containing carbon atoms, preferably k to 10 carbon atoms, the proportion of aliphatic radicals being 10 to 90 mol%, preferably 30 to 70 mol / O, R for H or OC-R ₂ -COOH and _{R 1 is} OH or NH-R 1 -NHp, and in which χ indicates the degree of polymerization, with the reduced specific viscosity of the Taigen solution as a measure in phenol / tetrachloroethane (in a weight ratio of 60: ' at 25 ° C 1.0 to 2.5 dl / g, preferably 1.5 to 2.0. ai / g, amounts to. 5- polyamides according to claim * f, characterized in that R is a Mixture of p-CMIs statistically distributed over the macromolecule. - or / and m-C ^ -H, - and - (CII-) .— means radicals. 309818/0937