CH716381B1 - Process for the production of polyamides. - Google Patents

Abstract

The invention relates to a process for the continuous production of amorphous or microcrystalline polyamides based on cycloaliphatic diamines and aliphatic dicarboxylic acids and a process for the continuous production of molding compounds containing these polyamides, comprising the steps: (a) The monomers and water present in the melt state are continuously fed separately without premixing at a temperature T0 into a first oligomerization zone, the amount of water, based on the weight of all starting materials for producing the polyamide, being at most 20% by weight; (b) The composition fed in in step (a) is subjected to an oligomerization in a first oligomerization zone without mass transfer with the environment at a temperature T1 and a pressure P1; (c) The reaction mixture from stage (b) is transferred to a second oligomerization zone and there the oligomerization is continued at a temperature T2 and a pressure P2, part of the water being separated off via the vapor phase and where T2> T1 and P2 <P1 ; (d) The reaction mixture from stage (c) is transferred to a post-condensation zone and further condensed there at a temperature T3 and a pressure P3 with the release of water, T3 ≥ T2 and P3 <P2 and a liquid-gaseous reaction mixture being formed; (e) The reaction mixture from stage (d) is fed to a discharge zone where the liquid polyamide in the melt is compacted after separation of the gas phase, mixed with fillers and additives in the case of the production of molding compounds, discharged and, after cooling, granulated.

Description

TECHNICAL AREA

The present invention relates to a process for the continuous production of amorphous or microcrystalline polyamides based on cycloaliphatic diamines and aliphatic dicarboxylic acids in which the monomers are metered directly into the reaction zone in the molten state.

STATE OF THE ART

Polyamides are among the polymers produced on a large scale worldwide and, in addition to the main areas of application, films, fibers and materials, serve a multitude of other uses.

Due to their very good optical and mechanical characteristics, the use of amorphous or microcrystalline polyamides or their molding compounds for applications in the field of automotive parts, electronics, optical components, panels, housings, visible surfaces, etc. is widespread. High-quality surfaces are used to support the "high-end quality" positioning of car equipment, household appliances, entertainment electronics, sports equipment and easy-to-clean industrial surfaces. In addition, high demands are placed on the material, which, in addition to its high-quality appearance, must be unbreakable, free-flowing, stretchable and low-warpage. This requires small changes in volume due to crystallization and low moisture absorption. Furthermore, excellent abrasion resistance and dynamic load capacity are required. In addition, due to the favorable optical properties of the amorphous or microcrystalline polyamides, such as haze, transparency and refractive index, optical applications such as glasses for sunglasses, lenses for technical devices, lights or signal lamps, optocouplers, housing or display material for mobile phones or LEDs, will be realized. These applications require high optical purity as well as improved transparency and clarity (haze) combined with high temperature resistance with very little discoloration of the materials.

In the field of transparent polyamides with high light permeability, excellent dynamic load capacity and excellent chemical resistance, two types of polymer in particular are known. Microcrystalline, transparent polyamides made from PACM with 35-60 mol% trans, trans isomers of bis (4-aminocyclohexyl) methane, 65-40 mol% of other diamines and dodecanedioic acid are known from DE 43 10 970 A1. The production of the microcrystalline polyamides was carried out in such a way that the starting materials were first dissolved in 35-45% by weight water under nitrogen in a polycondensation reactor under pressure at 170 ° C. The temperature was then raised to 215 ° C. and stirred at this temperature for 1 hour to obtain a homogeneous salt solution. After the temperature had been increased further to 280 ° C., the water formed by the polycondensation was used while the pressure was continuously released. After a reaction time of 2 hours at 280 ° C., the polyamide was withdrawn from the reactor.

From EP-A-0 725 101 amorphous, transparent polyamides with high chemical and thermal resistance and excellent dynamic resistance to fatigue load are known, which from MACM (bis (4-amino-3-methyl-cyclohexyl) methane ) and dodecanedioic acid are built up. Microcrystalline polyamides based on a mixture of the cycloaliphatic diamines PACM and MACM with aliphatic dicarboxylic acids are known from EP 1 369 447 A1, which have an optimal spectrum of properties with regard to transparency, haze, chemical resistance and dynamic loading. These polyamides are produced in known pressure vessels. The dissolution of the starting materials in 25-50% by weight of water (salt formation) is followed by a pressure phase at 260-310 ° C. This is followed by a relaxation phase at 260 to 310 ° C. The degassing is then carried out in a temperature range from 260 to 310 ° C. The polyamides are then discharged in strand form, cooled in a water bath at 5 - 80 ° C and granulated. The granulate is dried for 12 hours at 80 ° C. to a water content below 0.06%. The inventive, transparent molding compositions based on amorphous or microcrystalline polyamides are equipped with additives such as stabilizers, lubricants, fillers or impact modifiers by downstream mixing processes, in particular extrusion on single or multi-screw extruders with melt temperatures between 250 and 350 ° C.

WO 2014 198 757 A1 relates to a method for the continuous production of polyamide oligomers and a method for the production of partially crystalline or amorphous, thermoplastically processable polyamides from these polyamide oligomers. In this process, too, the starting materials are first converted into a homogeneous aqueous phase in a heatable and stirrable reactor and this aqueous phase is then continuously transferred from a storage vessel to a first precondensation unit consisting of a three-part tube bundle reactor with a heat exchanger. The reaction mixture is then released into a 2 L jacketed reactor and discharged from there either continuously as a solid or as a melt. Only the partially aromatic polyamide 6I / 6T is described as an amorphous polyamide. To produce the aqueous phase, 47% by weight of water, based on all starting materials, are used for this purpose. The precondensation in the first oligomerization unit takes place at 230 ° C. and 35 bar, and the pressure is released in the stirred reactor at 240 ° C. and 28 bar. In a post-condensation, the aqueous oligomer solution is then fed to a further expansion unit (separator) which operates at 315 ° C. and 6 bar. The polymer is then discharged.

The production of AABB polyamides usually begins with the formation of an aqueous salt solution from at least one diamine and at least one dicarboxylic acid and optionally other monomer components such as lactams, ω-amino acids, monoamines, monocarboxylic acids, etc. This salt solution is in one stirred and heated reactor and then transferred to a storage container with the process being carried out continuously, from where the reaction zone is then charged with a homogeneous salt solution. The formation of the salt solution is then followed by oligomerization in the liquid aqueous phase. To further increase the molecular weight through polycondensation, the aqueous solution is converted into the melt with controlled separation of water and an increase in temperature.

The known processes for the production of polyamides, in particular amorphous or microcrystalline polyamides, are still in need of improvement, especially with regard to the dosage and mixing of the monomers and the conduct of the process in oligomer formation and post-condensation. In particular, the known processes use a high concentration of water in order to be able to homogeneously dissolve the salts formed and to be able to store them in a stable manner over a long period of time. During the polycondensation, the water used as solvent plus the resulting water of reaction must be evaporated, which is inefficient from an energetic point of view. In addition, at least two voluminous containers with equipment are required in a continuous process for the salt production and storage of the salt solution.

OBJECT OF THE INVENTION

The present invention is based on the object of providing an improved process for the production of amorphous or microcrystalline polyamides. On the one hand, the polyamides should be made available in an energy-efficient manner and without the disadvantages of batch production. On the other hand, the complex salt production and storage should be dispensed with. Furthermore, the production process should be able to provide amorphous and microcrystalline polyamides with an extremely constant quality, in particular with regard to the solution viscosity and the end groups. In addition, the polyamides produced according to the invention should be distinguished by advantageous product properties, in particular a very good inherent color, a good film grade and a molecular weight distribution that is not too broad. In particular, the polyamides should have a very high degree of purity, e.g. only a very small number of black spots (inclusions), so that they are suitable, among other things, for use in optical applications. Furthermore, the typical disadvantages of a batch process, such as limitation of the batch size, loss of time due to filling, emptying and cleaning of the reaction vessel, etc. should also be avoided. A further aim is to provide an improved process for the continuous production of molding compounds which, in addition to the amorphous or microcrystalline polyamide, contain fillers and / or additives.

This object is achieved according to the invention by a process for the continuous production of amorphous or microcrystalline polyamides (A) based on cycloaliphatic diamines and aliphatic dicarboxylic acids according to claim 1, comprising the steps: (a) The monomers present in the melt state, comprising the at least one cycloaliphatic diamine (Y) and the at least one acyclic aliphatic dicarboxylic acid (X), and optionally further diamines (V) and aminocarboxylic acids (Z), and water are continuously fed into a first oligomerization zone separately without premixing at a temperature T0, wherein the amount of water, based on the weight of all starting materials for producing the polyamide (A), is at most 20% by weight; Optionally, monofunctional regulators (S), catalysts (K) and process auxiliaries (U) in the melt state or dissolved / dispersed in water are also fed to the first oligomerization zone; (b) The composition fed in in step (a) is subjected to an oligomerization in a first oligomerization zone without mass transfer with the environment at a temperature T1 and a pressure P1; (c) The reaction mixture from stage (b) is transferred to a second oligomerization zone and there the oligomerization is continued at a temperature T2 and a pressure P2, part of the water being separated off via the vapor phase and where T2> T1 and P2 <P1 ; (d) The reaction mixture from stage (c) is transferred to a post-condensation zone and further condensed there at a temperature T3 and a pressure P3 with the release of water, where T3 ≥ T2 and P3 <P2, and a liquid-gaseous reaction mixture is formed ; (e) The reaction mixture from stage (d) is fed to a discharge zone which operates in a temperature range T4, where the liquid polyamide (A) in the melt, after separation of the gas phase, compacts, optionally further degassed, discharged and after cooling is granulated.

Furthermore, this object is achieved by a process for the continuous production of a molding compound FM, containing at least one amorphous or microcrystalline polyamide (A), according to claim 2, comprising the steps: (a) The monomers present in the state of the melt, comprising the at least one cycloaliphatic diamine (Y) and the at least one acyclic aliphatic dicarboxylic acid (X), and optionally further diamines (V) and aminocarboxylic acids (Z), and water are continuously fed into a first oligomerization zone separately without premixing at a temperature T0, the The amount of water, based on the weight of all starting materials for producing the polyamide (A), is at most 20% by weight; Optionally, monofunctional regulators (S), catalysts (K) and process auxiliaries (U) in the melt state or dissolved / dispersed in water are also fed to the first oligomerization zone; (b) The composition fed in in step (a) is subjected to an oligomerization in a first oligomerization zone without mass transfer with the environment at a temperature T1 and a pressure P1; (c) The reaction mixture from stage (b) is transferred to a second oligomerization zone and there the oligomerization is continued at a temperature T2 and a pressure P2, part of the water being separated off via the vapor phase and where T2> T1 and P2 <P1 ; (d) The reaction mixture from stage (c) is transferred to a post-condensation zone and further condensed there at a temperature T3 and a pressure P3 with the release of water, where T3 ≥ T2 and P3 <P2, and a liquid-gaseous reaction mixture is formed ; (e) The reaction mixture from stage (d) is fed to a discharge zone, which operates in a temperature range T4, where the liquid polyamide (A) in the melt, after separation of the gas phase, compacts with fillers (B) and / or Additives (C) are mixed, optionally further degassed, discharged and, after cooling, granulated.

This object is also achieved by the polyamides (A) according to the invention according to claims 11 and 12.

This object is also achieved by the polyamide molding compositions (FM) according to claim 13.

This object is finally achieved by the use of the polyamides produced according to the invention according to claim 14 and the use of the polyamide molding compositions (FM) produced according to the invention according to claim 15.

Advantageous embodiments of the invention are contained in the subclaims.

DISCLOSURE OF THE INVENTION

Surprisingly, it has been found that the above-described object is achieved by a production process comprising the following features: the at least one cycloaliphatic diamine and the at least one acyclic aliphatic dicarboxylic acid and optionally other monomers and monofunctional regulators are not used as aqueous Salt solution are fed to the reaction zone, but as a melt in each case separately directly into the reaction zone; • Optional components such as monofunctional regulators (S), catalysts (K) and process auxiliaries (U) are also dosed directly into the reaction zone in the melt state or dissolved or dispersed in water; • the amount of water used, based on the weight of all starting materials for the polyamide (A), is a maximum of 20% by weight; • the water is also fed directly into the reaction zone; • the individual reaction zones are operated continuously; The amorphous or microcrystalline polyamides (A) produced according to the invention can optionally be mixed with fillers (B) and additives (C) in the discharge zone without the polyamide (A) having to be melted again for this purpose.

Thus, a first object of the invention is a process for the continuous production of amorphous or microcrystalline polyamides (A) based on cycloaliphatic diamines and aliphatic dicarboxylic acids, which includes the following process steps: a) The monomers present in the state of the melt, including the at least one cycloaliphatic diamine (Y) and the at least one acyclic aliphatic dicarboxylic acid (X), and optionally further diamines (V) and aminocarboxylic acids (Z), and water (W) are fed separately without premixing at a temperature T0 into a first oligomerization zone, where the amount of water based on the weight of all starting materials for producing the polyamide (A) is at most 20% by weight, preferably less than 15% by weight, particularly preferably 2 to 12% by weight and particularly preferably 4 to 10% by weight %, is; optionally, monofunctional regulators (S), catalysts (K) and process auxiliaries (U) in the melt state or dissolved or dispersed in water are likewise fed to the first oligomerization zone; the temperature T0 is preferably in a range from 130 to 200 ° C .; b) The composition fed in in stage (a) is subjected to an oligomerization in the first oligomerization zone without mass transfer with the environment at a temperature T1 and an absolute pressure P1, where T1 is preferably ≥ T0 and where the temperature T1 is preferably in a range of 190 up to 230 ° C. and the pressure P1 is preferably in the range from 20 to 50 bar; c) The reaction mixture from stage (b) is transferred to a second oligomerization zone and there the oligomerization is continued at a temperature T2 and a pressure P2, part of the water being separated off via the vapor phase and where T2> T1 and P2 <P1; the temperature T2 is preferably in a range from 240 to 270 ° C. and the pressure P2 is preferably in the range from 5 to 15 bar; d) The reaction mixture from stage (c) is transferred to a post-condensation zone and further condensed there at a temperature T3 and a pressure P3 with the release of water, where T3 ≥ T2 and P3 <P2, and a liquid-gaseous reaction mixture is formed; the temperature T3 is preferably in a range from 260 to 320 ° C. and the pressure P3 is preferably in the range from 1 to 4 bar; e) The reaction mixture from stage (d) is fed to a discharge zone which operates in a temperature range T4, where the liquid polyamide (A) in the melt, after separation of the gas phase, compacted, optionally further degassed, discharged and, after cooling, granulated becomes; the discharge zone preferably operates in a temperature range T4 from 240 to 300.degree.

Thus, a second object of the invention is a process for the continuous production of molding compositions FM, containing amorphous or microcrystalline polyamides (A) based on cycloaliphatic diamines and aliphatic dicarboxylic acids, which includes the following process steps: a) The present in the state of the melt Monomers comprising the at least one cycloaliphatic diamine (Y) and the at least one acyclic aliphatic dicarboxylic acid (X), and optionally further diamines (V) and aminocarboxylic acids (Z), and water (W) are separately at a temperature T0 in a fed into the first oligomerization zone, the amount of water based on the weight of all starting materials for the preparation of the polyamide (A) at most 20% by weight, preferably less than 15% by weight, particularly preferably 2 to 12% by weight and particularly preferably 4 to 10% by weight; optionally, monofunctional regulators (S), catalysts (K) and process auxiliaries (U) in the melt state or dissolved or dispersed in water are likewise fed to the first oligomerization zone; the temperature T0 is preferably in a range from 130 to 200 ° C .; b) The composition fed in in stage (a) is subjected to an oligomerization in the first oligomerization zone without mass transfer with the environment at a temperature T1 and an absolute pressure P1, where T1 is preferably ≥ T0 and where the temperature T1 is preferably in a range of 190 up to 230 ° C. and the pressure P1 is preferably in the range from 20 to 50 bar; c) The reaction mixture from stage (b) is transferred to a second oligomerization zone and there the oligomerization is continued at a temperature T2 and a pressure P2, part of the water being separated off via the vapor phase and where T2> T1 and P2 <P1; the temperature T2 is preferably in a range from 240 to 270 ° C. and the pressure P2 is preferably in the range from 5 to 15 bar; d) The reaction mixture from stage (c) is transferred to a post-condensation zone and further condensed there at a temperature T3 and a pressure P3 with the release of water, where T3 ≥ T2 and P3 <P2, and a liquid-gaseous reaction mixture is formed; the temperature T3 is preferably in a range from 260 to 320 ° C. and the pressure P3 is preferably in the range from 1 to 4 bar; e) The reaction mixture from stage (d) is fed to a discharge zone, which operates in a temperature range T4, where the liquid polyamide (A) in the melt, after separation of the gas phase, compacts with fillers (B) and / or additives (C) is mixed, optionally further degassed, discharged and, after cooling, granulated; the discharge zone preferably operates in a temperature range T4 from 240 to 300.degree.

With regard to the method outlined above, it is preferred that at least one of the temperature or pressure ranges mentioned below is selected and particularly preferably that all ranges are selected at the same time: the temperature T0 is in the range from 130 to 200 ° C .; the temperature T1 is in the range from 190 to 230 ° C; the temperature T2 is in the range from 240 to 270 ° C; the temperature T3 is in the range from 260 to 320 ° C; the temperature T4 is in the range from 240 to 300 ° C; the pressure P1 is in the range from 20 to 50 bar; the pressure P2 is in the range from 5 to 15 bar; the pressure P3 is in the range from 1 to 4 bar.

The pressure data given above and below always relate to the absolute pressure, i.e. the atmospheric pressure corresponds to approx. 1 bar.

The invention also provides the polyamides (A) obtainable in this way and the polyamide molding composition (FM) containing polyamide (A).

Another object of the invention is the use of the amorphous or microcrystalline polyamides (A) or the polyamide molding compounds (FM), which are produced by a method as defined above and below, preferably for the production of components in the areas of application Electro / electronics, automobiles and optics.

The inventive method has the following advantages: • The inventive method enables the continuous production of amorphous or microcrystalline polyamides (A) and the polyamide molding compounds (FM), so that the typical disadvantages of a batch process, such as limitation of the Batch size, loss of time due to filling, emptying and cleaning of the reaction vessel, tendency to form deposits on the inner wall of the reaction vessel, etc. can be avoided. • The handling of the components present in the melt (diamines, dicarboxylic acids and optionally aminocarboxylic acids and monofunctional regulators) allows these components to be cleaned effectively by filtration before they are fed into the first oligomerization zone. • The use of only small amounts of water and the avoidance of a separate salt formation in a stirred reactor leads, on the one hand, to a simplified process management with fewer system parts and a smaller volume of the system parts and, on the other hand, to a reduction in the evaporation energy. • The polyamide formation initially takes place without any material exchange with the environment, i. H. especially without the immediate removal of water as taught by many of the methods known from the prior art. Thus, the loss of more volatile monomers, such as. B. the diamines (V) or (Y), reduced or avoided. Since the second oligomerization zone of the process according to the invention reaches a quasi-steady state with regard to the molar mass, it is ensured that neither solidification nor molar mass build-up of the polyamide oligomers takes place, even if the polyamide oligomers have to be stored for a long time during a production interruption . The process according to the invention enables the direct production of polyamide molding compounds which contain the polyamide (A) in addition to fillers (B) and additives (C) without the polyamide (A) having to be in solid form, for example as dried granules, so that the process time until the molding compound (FM) is present is practically barely extended compared to the production of the polyamides (A).

DEFINITIONS OF TERMS

In the context of the present invention, the term “polyamide” (abbreviation PA) is understood to be a generic term which includes homopolyamides and copolyamides. The selected spellings and abbreviations for polyamides and their monomers correspond to those specified in ISO standard 16396-1 (2015 (D)). The abbreviations used therein are used synonymously for the IUPAC names of the monomers, in particular the following abbreviations for monomers occur: MACM for bis (4-amino-3-methyl-cyclohexyl) methane (also as 3,3'-dimethyl-4 , 4'-diaminodicyclohexylmethane referred to, CAS No. 6864-37-5), PACM for bis (4-amino-cyclohexyl) methane (also referred to as 4,4'-diaminodicyclohexylmethane, CAS No. 1761-71-3) , TMDC for bis (4-amino-3,5-dimethyl-cyclohexyl) methane (also known as 3,3 ', 5,5'-tetramethyl-4,4'-diaminodicyclohexylmethane, CAS No. 65962-45-0 ).

Compared with the partially crystalline polyamides, amorphous polyamides have no or only a very low, hardly detectable heat of fusion. In dynamic differential calorimetry (DSC) according to ISO 11357 (2013) at a heating rate of 20 K / min, the amorphous polyamides preferably show a heat of fusion of less than 5 J / g, particularly preferably a maximum of 3 J / g, very particularly preferably from 0 to 1 J / g. Due to their amorphous nature, amorphous polyamides do not have a melting point.

In addition to a glass transition temperature, microcrystalline polyamides also have a melting point. However, they have a morphology in which the crystallites have such a small dimension that a plate made from them with a thickness of 2 mm is still transparent, ie its light transmission is at least 90% and its haze is at most 3%, measured according to ASTM D 1003 -13 (2013). In the dynamic differential calorimetry (DSC) according to ISO 11357 (2013) at a heating rate of 20 K / min, microcrystalline polyamides preferably show a heat of fusion of 5 to 25 J / g, particularly preferably 5 to 22 J / g, very particularly preferably from 5 to 20 J / g. In comparison, partially crystalline polyamides show a pronounced melting peak in the DSC and have a heat of fusion of more than 25 J / g.

According to the present invention, a transparent polyamide is present if its light transmission measured according to ASTM D 1003-13 (2013) on plates with a thickness of 2 mm is at least 90% and its haze is at most 3%. When transparent polyamides are mentioned in the following, amorphous or microcrystalline polyamides are always meant that meet the above definitions with regard to transparency and heat of fusion.

The haze describes the scattering behavior of a substance, the transparency the light transmission through the substance. In the context of the present invention, under the haze or the transparency of the molded body produced from the polyamide molding compound (2 mm thick plates with width and length: 60 × 60 mm) according to ASTM D1003 on a Haze Gard Plus measuring device from BYK Gardner understood haze or transparency (total transmission) measured with CIE illuminant C at 23 ° C.

With regard to the polyamide (A) according to the invention, the monomers of the dicarboxylic acid and the diamine component and any aminocarboxylic acids or monofunctional regulators used form repeating units or end groups in the form of amides which are derived from the respective monomers. These generally make up at least 95 mol%, in particular at least 99 mol%, of all repeating units and end groups present in the polyamide. In addition, the polyamide can also contain small amounts of other repeating units which can result from degradation or secondary reactions of the monomers, for example the diamines.

Component (A)

In step (a) of the inventive method, the starting materials for the production of the amorphous or microcrystalline polyamide (A) are provided and transferred in the liquid state without prior mixing in a first oligomerization zone and mixed there. The starting materials for the production of polyamide (A) comprise at least the following components: (Y) at least one cycloaliphatic diamine (X) at least one acyclic aliphatic dicarboxylic acid, preferably at least one acyclic aliphatic dicarboxylic acid having 6 to 18 carbon atoms (W) water

Further starting materials for the production of polyamide (A), which can be provided in process stage (a), are the following components: (V) acyclic aliphatic diamines, preferably acyclic aliphatic diamines having 4 to 12 carbon atoms (Z) Aminocarboxylic acids (S) monofunctional regulators, in particular monocarboxylic acids (S1) or monoamines (S2) (K) catalysts (also referred to as polycondensation catalysts) (U) processing aids

The further components S, K, U can, depending on their nature, be introduced into a first oligomerization unit in the melt or in the form of an aqueous solution or dispersion.

The polyamide (A) is at least one transparent, cycloaliphatic polyamide of the formula VX / YX / Z, where at least the polyamide unit YX must be present (and thus the units VX and Z are optional) and where the monomer Units V, Y, X and Z are derived from the following molecules which are present in amidically bonded polyamide (A): (V): Acyclic aliphatic diamine, preferably having 4 to 12 carbon atoms; (Y): cycloaliphatic diamine; (X): Acyclic aliphatic dicarboxylic acid, preferably having 6 to 18 carbon atoms; (Z): aminocarboxylic acids, preferably with 6 to 12 carbon atoms.

The inventive polyamides (A) are based on cycloaliphatic diamines and acyclic aliphatic dicarboxylic acids, are amorphous or microcrystalline and have high transparency and low haze.

According to a preferred embodiment, the diamine (V) is selected from the group consisting of 1,4-butanediamine, 1,5-pentanediamine, 2-methyl-1,5-pentanediamine, hexanediamine, in particular 1,6-hexanediamine, 2,2,4-trimethyl-1,6-hexamethylenediamine, 2,4,4-trimethyl-1,6-hexamethylenediamine, nonanediamine, especially 1,9-nonanediamine, 2-methyl-1,8-octanediamine, 1.10 -Decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine and mixtures thereof. The acyclic, aliphatic diamines (V) selected from the group consisting of diamines having 6 to 10 carbon atoms, in particular 1,6-hexanediamine, 1,9-nonanediamine, 1,10-decanediamine and mixtures thereof, are particularly preferred.

Another preferred embodiment of the present invention provides that the cycloaliphatic diamine (Y) is selected from the group consisting of bis (4-amino-3-methyl-cyclohexyl) methane (MACM), bis (4 -amino-cyclohexyl) -methane (PACM), bis- (4-amino-3-ethyl-cyclohexyl) -methane, bis- (4-amino-3,5-dimethyl-cyclohexyl) -methane (TMDC), 2, 6-norbornanediamine (2,6-bis- (aminomethyl) -norbornane), 1,3-diaminocyclohexane, 1,4-diaminocyclohexanediamine, isophoronediamine, 1,3-bis- (aminomethyl) cyclohexane (BAC), 1,4-bis - (aminomethyl) cyclohexane, 2,2- (4,4'-diaminodicyclohexyl) propane and mixtures thereof. The cycloaliphatic diamines (Y) selected from the group consisting of bis (4-amino-3-methyl-cyclohexyl) methane (MACM) and bis (4-aminocyclohexyl) methane (PACM) and mixtures thereof are particularly preferred.

Another preferred embodiment of the present invention provides that the acyclic, aliphatic dicarboxylic acid (X) is selected from the group consisting of adipic acid, 1,7-heptanedioic acid, 1,8-octanedioic acid, 1,9-nonanedioic acid, 1 , 10-decanedioic acid, 1,11-undecanedioic acid, 1,12-dodecanedioic acid, 1,13-tridecanedioic acid, 1,14-tetradecanedioic acid, 1,15-pentadecanedioic acid, 1,16-hexadecanedioic acid, 1,17-heptadecanedioic acid, 1,18 -Octadecanedioic acid, and mixtures thereof. The acyclic, aliphatic dicarboxylic acids (X) selected from the group consisting of dicarboxylic acids having 10 to 16 carbon atoms, in particular 1,10-decanedioic acid, 1,12-dodecanedioic acid, 1,14-tetradecanedioic acid, 1,16-hexadecanedioic acid and mixtures are particularly preferred of this.

According to a further preferred embodiment of the present invention, the α, ω-aminocarboxylic acid (Z) is selected from the group consisting of α, ω-aminocaproic acid, α, ω-aminoheptanoic acid, α, ω-aminoctanoic acid, α, ω-aminonanoic acid , α, ω-aminodecanoic acid, α, ω-aminoundecanoic acid (AUA) and α, ω-aminododecanoic acid (ADA), particularly preferred are α, ω-aminoundecanoic acid and α, ω-aminododecanoic acid and mixtures thereof.

Within component (A), the monomer units are preferably selected such that the abbreviations V, X, Y, Z in the formula VX / YX / Z are derived from the following molecules which are amidically bonded in the polyamide (A) : V: acyclic aliphatic diamine with 6 or 10 carbon atoms; Y: cycloaliphatic diamine selected from the group consisting of MACM, PACM. X: acyclic aliphatic dicarboxylic acid with 10 to 16 carbon atoms, Z: α, ω-aminoundecanoic acid or α, ω-aminododecanoic acid.

In the case of component (A) according to the formula VX / YX / Z, it is particularly preferred that (V) is selected from the group consisting of 1,6-hexanediamine, methyl-1,8-octanediamine, 1,9-nonanediamine, 1 , 10-decanediamine, (Y) is selected from the group consisting of bis (4-amino-3-methyl-cyclohexyl) methane (MACM) and bis (4-amino-cyclohexyl) methane (PACM), (X) is selected from the group 1,12-dodecanedioic acid, 1,16-hexadecanedioic acid, (Z) is selected as α, ω-aminododecanoic acid.

The amorphous or microcrystalline polyamide (A) is preferably selected from the group consisting of the polyamides (PA): MACM6, MACM8, MACM9, MACM10, MACM12, MACM14, MACM16, MACM18, PACM6, PACM8, PACM9, PACM10, PACM12 , PACM14, PACM16, PACM18, TMDC6, TMDC8, TMDC9, TMDC10, TMDC12, TMDC14, TMDC16, TMDC18 and copolymers thereof. Preferred copolymers (copolyamides) are MACM10 / PACM10, MACM12 / PACM12, MACM14 / PACM14, MACM16 / PACM16, MACM18 / PACM18, TMDC10 / PACM10, TMDC12 / PACM12, TMDC14 / PACM14, TMDC16 / PACMAC / PACM18, MACDC18 / MACM10 / MACM16, MACM12 / MACM16, PACM10 / PACM12, PACM10 / PACM16 and PACM12 / PACM16.

The polyamide (A) is particularly preferably MACM10, PACM10, MACM12, PACM12, MACM14, PACM14, MACM16, PACM16, TMDC10, TMDC12, TMDC14, TMDC16 or copolyamides from two or more of these systems. Particularly preferred copolyamides are MACM10 / PACM10, MACM12 / PACM12, MACM14 / PACM14, MACM16 / PACM16, MACM10 / MACM12, MACM10 / MACM16, MACM12 / MACM16, PACM10 / PACM12, PACM10 / PACM16 and PACM12 / PACM16.

The polyamide (A) is particularly preferably selected from the group consisting of the polyamides (PA) MACM12, PACM12 and MACM12 / PACM12.

With regard to the processability and the profile of properties, it is found to be advantageous if the cycloaliphatic polyamide (A) has a solution viscosity (determined on the basis of a solution of 0.5 g of polymer dissolved in 100 ml of m-cresol at 20 ° C. in accordance with ISO 307 (2007) ) in the range from ηrel = 1.4 to 2.5, preferably in the range from ηrel = 1.5 to 2.0, in particular in the range from 1.55 to 1.90.

It is also advantageous if the transparent polyamide (A) is an amorphous polyamide with a melting enthalpy of less than 5 J / g, or a microcrystalline polyamide with a melting enthalpy in the range from 5 to 25 J / g.

In addition to the monomers V, Y, X, Z and the water, further components can be metered into a first oligomerization zone in stage (a). These further components are preferably selected from catalysts (K), monofunctional chain regulators (S), processing aids (U) and mixtures thereof.

The amorphous or microcrystalline polyamides (A) can contain at least one monofunctional carboxylic acid (S1) or monofunctional amine (S2) as a regulator (S) in copolymerized form. The monofunctional regulators (S) serve to end-cap the polyamides produced according to the invention. In principle, all monocarboxylic acids (S1) which are capable of reacting with at least some of the available amino groups under the reaction conditions of the polyamide condensation are suitable. Suitable monocarboxylic acids (S1) are aliphatic monocarboxylic acids, alicyclic monocarboxylic acids and aromatic monocarboxylic acids. These include formic acid, acetic acid, propionic acid, n-, iso- or tert-butyric acid, valeric acid, trimethyl acetic acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, cyclohexanoic acid, benzoic acid , Methylbenzoic acids, α-naphthoic acid, β-naphthoic acid, phenylacetic acid, oleic acid, ricinoleic acid, linoleic acid, linolenic acid, erucic acid, acrylic acid, methacrylic acid and mixtures thereof.

The monocarboxylic acid (S1) is particularly preferably selected from acetic acid, propionic acid, benzoic acid, stearic acid and mixtures thereof. In a special embodiment, the amorphous or microcrystalline polyamides (A) contain exclusively benzoic acid as monocarboxylic acid (S1) in polymerized form.

The amorphous or microcrystalline polyamides (A) can contain at least one monoamine (S2) in copolymerized form. The monoamines (S2) serve to end-cap the polyamides produced according to the invention. In principle, all monoamines which are capable of reacting with at least some of the available carboxylic acid groups under the reaction conditions of the polyamide condensation are suitable. Preferred monoamines (S2) are aliphatic monoamines. These include methylamine, ethylamine, propylamine, butylamine, hexylamine, heptylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, cyclohexylamine, dicyclohexylamine, and mixtures thereof.

The amount of water provided in stage (a) and fed directly into the first oligomerization zone, based on the sum of all starting materials for polyamide (A), is a maximum of 20% by weight, preferably less than 15% by weight, particularly preferred 2 to 12% by weight and very particularly preferably 4 to 10% by weight.

In a special embodiment, process auxiliaries (U), monofunctional regulators (S) and / or polycondensation catalysts (K) are added to the water to simplify the charging of the first oligomerization zone (stage a) if they are soluble or dispersible in water.

Preferred processing aids (U) are inorganic and organic stabilizers and defoamers.

At least one catalyst (K) can be used for the preparation according to the invention of the amorphous or microcrystalline polyamides (A). Suitable catalysts are preferably selected from inorganic and / or organic phosphorus, tin or lead compounds and mixtures thereof.

Tin compounds suitable as catalysts are, for. B. tin (II) oxide, tin (II) hydroxide, tin (II) salts of mono- or polybasic carboxylic acids, e.g. B. tin (II) dibenzoate, tin (II) di (2-ethylhexanoate), tin (II) oxalate, dibutyltin oxide, butyltin acid (C4H9-SnOOH), dibutyltin dilaurate, etc. Suitable lead compounds are e.g. B. lead (II) oxide, lead (II) hydroxide, lead (II) acetate, basic lead (II) acetate, lead (II) carbonate etc.

Preferred catalysts are phosphorus compounds such as phosphoric acid, phosphorous acid, hypophosphorous acid, phenylphosphonic acid, phenylphosphinic acid and / or their salts with mono- to trivalent cations, such as. B. Na, K, Mg, Ca, Zn or Al, and / or their esters, such as. B. triphenyl phosphate, triphenyl phosphite or tris (nonylphenyl) phosphite. Hypophosphorous acid and its salts, such as, for example, sodium hypophosphite, are particularly preferred as the catalyst.

The catalysts (K) are preferably used in an amount of 0.005 to 1.0% by weight, based on the total weight of all starting materials used in stage (a).

Hypophosphorous acid and / or a salt of hypophosphorous acid in an amount of 50 to 1000 ppm, particularly preferably 100 to 500 ppm, based on the total amount of the components suitable for polyamide formation (= sum of components (V), (X), (Y), (Z) and (S)) are used.

At least one chain regulator can be used to regulate the molar mass. Suitable chain regulators are, on the one hand, the aforementioned monocarboxylic acids (S1) and monoamines (S2) and, on the other hand, bifunctional diamines and diacids, i.e. also one of the diamine components (V) or (Y) or the dicarboxylic acid component (X), if these are in a stoichiometric excess can be used. Such a suitable chain regulator is thus, for example, MACM as component (Y) or 1,12-dodecanedioic acid as component (X). The preferred amount of these chain regulators used is in a range from 5 to 500 mmol per kg of polyamide (A), preferably 10 to 200 mmol per kg of polyamide (A). In the process according to the invention for producing the polyamides (A), the molar ratio of the total diamines used to the total dicarboxylic acids used is preferably in the range from 1.05 to 0.95, particularly preferably in the range from 1.02 to 0.98, and with particular preference the diamines and dicarboxylic acids are equimolar used.

CONTINUOUS PROCESS FOR PRODUCING THE POLYAMIDE (A) AND THE POLYAMIDE MOLDING COMPOUNDS (FM)

Stage (a)

According to the invention, the polyamide-forming monomers, i.e. the diamines (V) and (Y), the dicarboxylic acids (X) and the aminocarboxylic acids (Z) and, if necessary, also the monofunctional regulators (S) are melted either in separate storage containers or continuously operating melting units , the melting and storage preferably taking place under inert gas. By means of metering pumps, the abovementioned components are continuously conveyed in the required amount to a first oligomerization zone, where they are fed in via separate inlet openings. On the route from the storage tank or from the melting unit to the entry into the first oligomerization zone, the components are heated from the storage or melting temperature TL (TL> Tm; Tm = melting temperature of the component under consideration) to temperature T0. The water (W) heated to a temperature T0 is also fed separately into the first oligomerization zone.

The optionally used components (K) and (U) can be metered into the first oligomerization zone either in the melt or as an aqueous solution or dispersion. For this purpose, these components can be dissolved or dispersed in the water (W). Components (K) and (U), regardless of whether they are in the form of a melt or an aqueous solution / dispersion, are heated to temperature T0 before being fed into the first oligomerization zone. The temperature T0 is preferably in a range from about 130 to 200.degree. C., particularly preferably from 140 to 190.degree.

Stage (b)

In the first oligomerization zone, the components fed in are mixed and the formation of polyamide oligomers (precondensation) is initiated at a temperature T1 and a pressure P1. The pressure P1 is clearly above the water vapor partial pressure established at the temperature T1, which ensures that the reaction is carried out in one phase. There is thus no exchange of substances with the environment, in particular no volatile constituents, in particular water, of the reaction mixture are evaporated and given off to the environment via the gas phase. The mass per unit of time of the reaction mixture which leaves the first oligomerization zone via the discharge valve is thus equal to the mass of the starting materials fed in for the polyamide (A).

The composition fed in in stage (a) is heated rapidly from a temperature T0 on entry to a temperature T1 as it passes through the first oligomerization zone. This temperature is then maintained until it exits this zone. A pressure P1 is set by means of a pump, which is above the partial pressure of the water vapor at T1. This ensures that there is no gas phase in the mixture, i.e. that neither water nor monomers or additives are in the gas phase.

The temperature T1 in the first oligomerization zone is preferably in a range from about 190 to 230.degree. C., particularly preferably from 200 to 220.degree.

The pressure P1 in the first oligomerization zone is preferably in a range from 20 to 50 bar, particularly preferably in a range from 25 to 40 bar.

Stage (c)

The reaction mixture from the first oligomerization zone is transferred to a second oligomerization zone and there the oligomerization is continued at a temperature T2 and a pressure P2 until a quasi-steady state, characterized by a constant mean solution viscosity, is reached, with part of the water over the vapor phase is deposited and where T2> T1 and P2 <P1. In this stage, the reaction mixture is transferred from the first to the second oligomerization zone and the polycondensation is advanced at a temperature T2 and a pressure P2 until the conversion, based on the polycondensation of the diamines and dicarboxylic acids, has preferably reached a value of 70 to 90% . In this case, water is separated out via the vapor phase, while the polyamide oligomers are still in the liquid state. A heated gas can flow through the second oligomerization zone to remove water.

The temperature T2 in the second oligomerization zone is preferably in a range from about 240 to 270.degree. C., particularly preferably from 245 to 265.degree.

The pressure P2 in the second oligomerization zone is preferably in a range from 5 to 15 bar, particularly preferably in a range from 6 to 12 bar.

After passing through the second oligomerization zone, the polyamide oligomers preferably have a number-average molar mass Mn in the range from 1000 to 8000 g / mol, particularly preferably in the range from 1200 to 4000 g / mol.

Stage (d)

In this stage, the polyamide oligomers of stage (c) are transferred to a post-condensation zone and condensed further at a temperature T3 and a pressure P3 with the release of water. Since the gas phase is not separated off in this stage, a liquid-gaseous reaction mixture is formed. T3 ≥ T2 and P3 <P2. Pressure P3 is preferably less than or equal to 4 bar, particularly preferably less than 3 bar and in particular equal to atmospheric pressure (1 bar). The temperature T3 is preferably in a range from 260 to 320.degree. C., particularly preferably in the range from 270 to 310.degree.

Stage (s)

In this stage, the reaction mixture (product stream) from stage (d) is fed to a discharge zone, and the liquid components of the mixture are first separated from the gaseous components of the mixture. The water released in stage (d) is separated from the liquid polyamide (A) and then condensed. The liquid polyamide (A), which is in the melt, is compacted, discharged as a strand and, after cooling, granulated. If appropriate, fillers and additives can be incorporated into the polyamide (A) within the discharge zone. At the end of the discharge zone, either the polyamide (A) or the polyamide molding compound (FM), optionally provided with further additives (B) and (C), is present. Polyamide (A) or molding compound (FM) are discharged and, after cooling, fed to a granulator. Optionally, degassing or a zone with reduced pressure can also be integrated into the discharge unit, as a result of which the polyamide (A) can be subjected to a further post-condensation. The discharge zone preferably operates in a temperature range (T4) from 240 to 300.degree. C., particularly preferably in a range from 250 to 290.degree.

During the entire production process, the polyamide oligomers or the polyamides remain in the liquid phase and a solid phase is never obtained. The high molecular weight amorphous or microcrystalline polyamides (A) or the polyamide molding compound (FM) are only solidified when discharged in stage (e).

To carry out the oligomerization in stages (b) and (c), the first and second oligomerization zones can each consist of a reactor or can comprise several identical or different reactors. In the simplest case, a single reactor is used as the oligomerization zone. If several reactors are used, they can each have the same or different temperatures and / or pressures. If several reactors are used, they can each have the same or different mixing characteristics. The individual reactors are preferably subdivided one or more times by means of internals.

Suitable reaction apparatus for the oligomerization are known to the person skilled in the art. These include the commonly used reactors for liquid and gas-liquid reactions, such as. B. tubular reactors, stirred kettles, etc., which can optionally be subdivided by internals. The reactors can preferably contain beds or packings. These include B. static mixers, packings such as Raschig Pall rings or packings such as Sulzer packings, Raschig Ralu pack or fillings made of monofilament fabrics. Thus, the residence time characteristic can be modified, e.g. B. to achieve a narrower residence time distribution.

Preferably, at least one tubular reactor each is used for the oligomerization in stages (b) and (c). A preferred embodiment of a tubular reactor for stages (b) and (c) is the tube bundle reactor. In a preferred embodiment, the oligomerization zone used for the reaction in stages (b) and (c) thus comprises at least one tubular reactor each or consists of at least one tubular reactor. This at least one tubular reactor preferably contains internal heating and mixing elements. In a preferred embodiment, the tubular reactors used for the first oligomerization zone are equipped with mixing elements.

The tubular reactors used for the reaction in stage (b) can be operated largely isothermally in a suitable embodiment. For this purpose, heat transfer surfaces can be arranged outside or inside the reactors in a suitable manner. The entire walls of the tubular reactor are preferably designed as heat transfer surfaces, but at least the area where the components are fed into the oligomerization zone, so that, for example, the temperature of the starting materials can be increased from T0 at the entry point of the first oligomerization zone to T1 in the upper part of the oligomerization zone.

The residence time of the reaction mixture in the oligomerization zone in stage (b) and (c) is preferably in a range from 5 to 60 minutes, particularly preferably from 10 to 30 minutes. The residence time in the post-condensation zone in stage (d) is in the range from 3 to 30 minutes, preferably in the range from 5 to 20 minutes.

Process step (e) is preferably carried out by means of extruders, kneaders, strand degassers or a combination of at least two of these devices. Stage (e) is particularly preferably carried out using a twin-screw extruder. In a preferred embodiment, the gas phase is separated off from the reaction mixture from stage (d) at the beginning of the discharge zone and condensed in a separate container. Thus, practically all of the water that was released during the expansion in the post-condensation zone (stage d) can be separated off shortly after the reaction mixture has entered the extruder. Depending on the required target viscosity, no further degassing of the polyamide melt is required on the remaining conveying path in the extruder. However, if a very high viscosity is to be achieved, the extruder can have one or more degassing zones.

Known vented extruders are usually constructed in such a way that the material flow to be vented is usually fed to the drive side in a feed zone of the extruder screw (s) and the extrudate is vented and conveyed to the screw tip. After passing through one or more zones of increased pressure in the extruder, the pressure is usually relieved of pressure downstream, during which degassing takes place. The degassing can take place at an overpressure that is reduced compared to the feed zone, at atmospheric pressure or with the aid of a vacuum. If fillers and reinforcing materials and / or additives are optionally added to the polyamide (A) at this stage, the extruder is equipped with additional metering points for these components. Components (B) and (C) are added after the gas phase has been separated off in the discharge zone.

The disclosed amorphous or microcrystalline polyamides (A) obtained by the process according to the invention preferably have a number-average molar mass Mn in a range from 10,000 to 25,000 g / mol and preferably a weight-average molar mass Mw in the range from 18,000 up to 50,000 g / mol. Furthermore, the amorphous or microcrystalline polyamides (A) obtained by the process according to the invention preferably have a polydispersity PD (= Mw / Mn) of at most 3, particularly preferably at most 2.5, in particular in the range from 1.8 to 2.5.

The amorphous or microcrystalline polyamides (A) or molding compositions (FM) obtainable by the process according to the invention have advantageous properties. In particular, they have a very small number of inclusions, have a good film grade and a low inherent color. In addition, the polyamides and molding compositions according to the invention are characterized by a high degree of constancy of the properties, such as the solution viscosity or the end groups.

Polyamide molding compound FM

Another object of the invention is a polyamide molding composition (FM) which contains an amorphous or microcrystalline polyamide (A) produced by the inventive method described.

A polyamide molding compound (FM) containing the following components or consisting of the following components is preferred: (A) 25 to 100% by weight of amorphous or microcrystalline polyamide, as defined above, (B) 0 to 70% by weight % of at least one filler, (C) 0.01 to 30% by weight of at least one additive different from (A) and (B), components (A) to (C) totaling 100% by weight.

The polyamide molding compositions (FM) according to the present invention contain components (A) to (C) or preferably consist exclusively of components (A) to (C), with the proviso that components (A ) to (C) add a total of 100% by weight. The specified ranges of the quantities specified for the individual components (A) to (C) are to be understood in such a way that an arbitrary quantity can be selected for each of the individual components within the specified ranges, provided that the strict requirement is met that the sum of all components ( A) to (C) gives 100% by weight.

Component (B)

Component (B) is a filler which is contained in 0 to 70% by weight in the polyamide molding compound (FM). The fillers can be both fibrous and particulate, individually or as a mixture. Component (B) can therefore contain fibrous fillers (reinforcing agents) or particulate fillers or else a mixture of reinforcing agents and particulate fillers.

According to a preferred embodiment of the present invention, component (B) is 10 to 60% by weight, more preferably 20 to 55% by weight and particularly preferably 25 to 50% by weight in the polyamide molding composition (FM), these quantities being based on the sum of components (A) to (C) or the total weight of the polyamide molding compound (FM).

It is particularly preferred if component (B) consists exclusively of reinforcing agents selected from the group consisting of glass fibers, carbon fibers, boron fibers, aramid fibers, basalt fibers and mixtures thereof. According to a preferred embodiment of the polyamide molding composition according to the invention, component (B) is formed entirely from glass fibers.

The glass fibers used have a cross-sectional area that is either circular (or synonymously round) or non-circular (or synonymously flat), in the latter case the dimensional ratio of the main cross-sectional axis to the minor cross-sectional axis at least 2, preferably in the range from 2.5 to 4.5.

The reinforcement with glass fibers can be done with short fibers (e.g. cut glass with a length of 2 to 50 mm) or continuous fibers (long glass or rovings). In a preferred embodiment, the glass fibers used according to the invention are short glass fibers with a diameter in the range from 6 to 20 and preferably from 9 to 12 μm. The glass fibers are in the form of cut glass with a length of 2 to 50 mm. In particular, E and / or S glass fibers are used according to the invention. But it can also all other types of fiberglass, such. B. A, C, D, M, R glass fibers or any mixtures thereof or mixtures with E and / or S glass fibers can be used. There are the usual for polyamide sizes, such. B. various aminosilane sizes, used, high temperature stable sizes are preferred.

In the case of flat glass fibers, i.e. glass fibers with a non-circular cross-sectional area, those with a dimensional ratio from the main cross-sectional axis to the secondary cross-sectional axis perpendicular to it of more than 2, preferably from 2.5 to 4.5, in particular from 3 to 4, are preferably used. These so-called flat glass fibers have an oval, elliptical, elliptical (so-called cocoon fiber), polygonal, rectangular or almost rectangular cross-sectional area provided with constriction (s). Another characteristic feature of the flat glass fibers used is that the length of the main cross-sectional axis is preferably in the range from 6 to 40 μm, in particular in the range from 15 to 30 μm and the length of the secondary cross-sectional axis in the range from 3 to 20 μm, in particular in the range of 4 to 10 µm.

Mixtures of glass fibers with circular and non-circular cross-sections can also be used to reinforce the molding compositions according to the invention, the proportion of flat glass fibers preferably predominating, i.e. more than 50% by weight of the total mass of the fibers. The glass fibers can be provided with a size suitable for thermoplastics, in particular for polyamide, containing an adhesion promoter based on an amino or epoxysilane compound.

The flat glass fibers of component (B) are preferably selected as E-glass fibers according to ASTM D578-00 with a non-circular cross section, preferably from 52 to 62% silicon dioxide, 12 to 16% aluminum oxide, 16 to 25% calcium oxide , 0 to 10% borax, 0 to 5% magnesium oxide, 0 to 2% alkali oxides, 0 to 1.5% titanium dioxide and 0 to 0.3% iron oxide. The glass fibers of component (B), as flat E-glass fibers, preferably have a density of 2.54 to 2.62 g / cm 3, a tensile modulus of elasticity of 70 to 75 GPa, a tensile strength of 3000 to 3500 MPa and an elongation at break of 4.5 to 4.8%, the mechanical properties being determined on individual fibers with a diameter of 10 µm and a length of 12.7 mm at 23 ° C and a relative humidity of 50%.

Component (B) can further contain particulate fillers, optionally in surface-treated form, selected from the following group: kaolin, calcined kaolin, talc, talc, mica, silicate, quartz, titanium dioxide, wollastonite, amorphous silicas, magnesium carbonate, Magnesium hydroxide, chalk, lime, feldspar, barium sulfate, solid or hollow glass spheres or ground glass, in particular ground glass fibers and mixtures of the elements from this group. Glass microspheres with an average diameter in the range from 5 to 100 μm are particularly preferred as fillers, since these tend to give the molded part isotropic properties and thus allow molded parts to be produced with low warpage.

According to a preferred embodiment of the present invention, component (B) consists exclusively of a glass filler selected from the group consisting of glass fibers, ground glass fibers, glass particles, glass flakes, glass spheres, glass hollow spheres or combinations of the aforementioned. If glass spheres or glass particles are selected as component (B), their mean diameter is 0.3 to 100 μm, preferably 0.7 to 30 μm, particularly preferably 1 to 10 μm.

Another preferred embodiment of the present invention provides that the type of glass of component (B) is selected from the group consisting of E-glass, ECR-glass, S-glass, A-glass, AR-glass and R- Glass, in particular E and S glass, and mixtures of these types of glass.

According to a preferred embodiment, component (B) is a high-strength glass fiber or so-called S-glass fiber. This is preferably based on the ternary system silicon dioxide-aluminum oxide-magnesium oxide or on the quaternary system silicon dioxide-aluminum oxide-magnesium oxide-calcium oxide, with a composition of 58 to 70% by weight silicon dioxide (SiO2), 15 to 30% by weight aluminum oxide ( Al2O3), 5 to 15% by weight magnesium oxide (MgO), 0 to 10% by weight calcium oxide (CaO) and 0 to 2% by weight other oxides, such as zirconium dioxide (ZrO2), boron oxide (B2O3), titanium dioxide (TiO2), iron oxide (Fe2O3), sodium oxide, potassium oxide or lithium oxide (Li2O) is preferred.

It is particularly preferred if the high-strength glass fiber has the following composition: 62 to 66% by weight silicon dioxide (SiO2), 22 to 27% by weight aluminum oxide (Al2O2), 8 to 12% by weight magnesium oxide ( MgO), 0 to 5% by weight calcium oxide (CaO), 0 to 1% by weight other oxides, such as zirconium dioxide (ZrO2), boron oxide (B2O3), titanium dioxide (TiO2), iron oxide (Fe2O3), sodium oxide, potassium oxide and lithium oxide (Li3O).

The high-strength glass fibers (S-glass fibers) preferably have a tensile strength of at least 3700 MPa, preferably of at least 3800 or 4000 MPa, and / or an elongation at break of at least 4.8%, preferably of at least 4.9 or 5.0% and / or a tensile strength -E modulus of more than 75 GPa, preferably of more than 78 or 80 GPa, these glass properties on single fibers (pristine single filaments) with a diameter of 10 µm and a length of 12.7 mm at a temperature of 23 ° C and a relative humidity of 50% are to be determined.

Component (C)

The polyamide molding composition (FM) according to the invention contains 0.01 to 30% by weight of at least one additive as component (C), which is different from components (A) and (B).

According to a preferred embodiment, the polyamide molding composition (FM) according to the invention preferably contains 0.02 to 20% by weight of at least one additive as component (C).

According to a preferred embodiment, component (C) is selected from the group consisting of lubricants, heat stabilizers, processing stabilizers, processing aids, viscosity modifiers, oxidation retardants, agents against thermal decomposition and decomposition by ultraviolet light, UV blockers, lubricants and mold release agents, colorants, in particular dyes, inorganic pigments, organic pigments, plasticizers, flame retardants, impact modifiers and mixtures thereof.

According to a particularly preferred embodiment, the polyamide molding composition (FM) contains as component (C) at least one lubricant, this preferably in a proportion of 0 to 2% by weight, particularly preferably from 0.01 to 2.0% by weight , based in each case on the total weight of components (A) to (C). Al, alkali, alkaline earth salts, esters or amides of fatty acids with 10 to 44 carbon atoms and preferably with 14 to 44 carbon atoms are preferred, the metal ions Na, Mg, Ca and Al being preferred and Ca or Mg particularly preferred are. Particularly preferred metal salts are Ca stearate and Ca montanate and also Al stearate. The fatty acids can be monovalent or divalent. Examples are pelargonic acid, palmitic acid, lauric acid, margaric acid, dodecanedioic acid, behenic acid and the particularly preferred stearic acid, capric acid and montanic acid (mixture of fatty acids with 30 to 40 carbon atoms).

Furthermore, aliphatic alcohols, which can be monohydric to tetrahydric, are preferred as lubricants. These alcohols are preferably selected from the group consisting of n-butanol, n-octanol, stearyl alcohol, ethylene glycol, propylene glycol, neopentyl glycol, glycerol, pentaerythritol and mixtures thereof, with glycerol and pentaerythritol being preferred.

In addition, aliphatic amines, which can be 1- to 3-valent, are preferred lubricants. Preferred amines are selected from the group consisting of stearylamine, ethylenediamine, propylenediamine, hexamethylenediamine, di (6-aminohexyl) amine and mixtures thereof, with ethylenediamine and hexamethylenediamine being particularly preferred.

Preferred esters or amides of fatty acids are selected from the group consisting of glycerol distearate, glycerol tristearate, ethylene diamine distearate, glycerol monopalmitate, glycerol trilaurate, glycerol monobehenate, pentaerythritol tetrastearate and mixtures thereof. In addition, white oils or silicone oils can also be used.

According to a further preferred embodiment, the polyamide molding compound (FM) contains as component (C) at least one heat stabilizer, this preferably in a proportion of 0 to 3% by weight, particularly preferably from 0.01 to 2.0% by weight , based in each case on the total weight of components (A) to (C).

According to a preferred embodiment, the heat stabilizers are selected from the group consisting of: Compounds of mono- or divalent copper, for example salts of mono- or divalent copper with inorganic or organic acids or mono- or dihydric phenols, the oxides of a - Or divalent copper, or the complex compounds of copper salts with ammonia, amines, amides, lactams, cyanides or phosphines, preferably Cu (I) or Cu (II) salts of the hydrohalic acids, the hydrocyanic acids or the copper salts of the aliphatic carboxylic acids. The monovalent copper compounds CuCI, CuBr, Cul, CuCN and Cu2O, and the divalent copper compounds CuCl2, CuSO4, CuO, copper (II) acetate or copper (II) stearate are particularly preferred. The copper compounds are advantageously used in combination with other metal halides, in particular alkali halides such as Nal, Kl, NaBr, KBr, the molar ratio of metal halide to copper halide being 0.5 to 20, preferably 1 to 10 and particularly preferably 3 to 7. • Stabilizers based on secondary aromatic amines, these stabilizers preferably being present in an amount of 0.01 to 2.0, preferably from 0.02 to 1.5% by weight, • Stabilizers based on sterically hindered phenols, these stabilizers preferably in an amount of 0.01 to 1.5 , preferably from 0.02 to 1.0% by weight, and • phosphites and phosphonites, and • mixtures of the aforementioned stabilizers.

Particularly preferred examples of stabilizers based on secondary aromatic amines which can be used according to the invention are adducts of phenylenediamine with acetone (Naugard A), adducts of phenylenediamine with linoles, Naugard 445, N, N'-dinaphthyl-p-phenylenediamine, N-phenyl- N'-cyclohexyl-p-phenylenediamine or mixtures of two or more thereof.

In principle, all compounds with a phenolic structure which have at least one sterically demanding group on the phenolic ring are suitable as sterically hindered phenols. Preferred examples of stabilizers based on sterically hindered phenols which can be used according to the invention are N, N'-hexamethylene-bis-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionamide, bis- (3,3-bis- (4'-hydroxy-3'-tert-butylphenyl) butanoic acid) glycol ester, 2,1'-thioethylbis (3- (3,5-di.tert-butyl-4-hydroxyphenyl) propionate, 4-4 '-Butylidene-bis (3-methyl-6-tert-butylphenol), triethylene glycol 3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate or mixtures of two or more of these stabilizers.

Preferred phosphites and phosphonites are triphenyl phosphite, diphenylalkyl phosphite, phenyl dialkyl phosphite, tris (nonylphenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite, distearylphentaerythritol diphosphite, tris (2,4-di-tert-butylphenylphosphite, tris (2,4-di-tert-butylphenylphosphite, diaphosphitol bis (2,4-di-pentylphenyl) phosphite, tris (2,4-di-tert-butylphenylphosphite, di-phosphitodiphosphite, di-phosphitodiphosphite, tris (2,4-di-tert-butyl-phosphitodiphosphite) tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, diisodecyloxypentaerythritol diphosphite, bis (2,4-di-tert-butyl-6-methylphenyl) pentaerythritol diphosphite, bis (2,4 , 6-tris (tert-butylphenyl)) pentaerythritol diphosphite, tristearyl sorbitol triphosphite, tetrakis (2,4-di-tert-butylphenyl) -4,4'-biphenylenediphosphonite, 6-isooctyloxy-2,4,8,10-tetra -tert-butyl-12H-dibenz- [d, g] -1,3,2-dioxaphosphocine, 6-fluoro-2,4,8,10-tetra-tert-butyl-12-methyl-dibenz [d, g ] -1,3,2-dioxaphosphocine, bis (2,4-di-tert-butyl-6-methylphenyl) methyl phosphite and bis (2,4-di-tert-butyl-6-methylphenyl) ethyl phosphite. Tris [2-tert-butyl-4-thio (2'-methyl-4'-hydroxy-5'-tert-butyl) -phenyl-5-methyl] phenyl-phosphite and tris (2,4-di -tert-butylphenyl) phosphite (Hostanox PAR24, Irgafos 168).

A preferred embodiment of the heat stabilizer consists of a combination of organic heat stabilizers (in particular Irgafos 168 and Irganox 1010), a bisphenol A-based epoxy (in particular Epikote 1001) and a copper stabilizer based on Cul and Kl. A commercially available stabilizer mixture, consisting of From organic stabilizers and epoxides, for example, Irgatec NC66 from Ciba Spez. GmbH or Recyclobyk 4371 is particularly preferred. Heat stabilization based exclusively on Cul and Kl.

Examples of oxidation retarders and heat stabilizers are phosphites and other amines (e.g. TAD), hydroquinones, various substituted representatives of these groups and their mixtures in concentrations of up to 1% by weight, based on the weight of components (A) to ( C) called.

Various substituted resorcinols, salicylates, benzotriazoles and benzophenones may be mentioned as UV stabilizers, which are generally used in amounts of up to 2% by weight, based on the weight of the polyamide molding composition (I).

Inorganic pigments such as titanium dioxide, ultramarine blue, iron oxide and carbon black and / or graphite, furthermore organic pigments such as phthalocyanines, quinacridones, perylenes and dyes such as nigrosine and anthraquinones can be added as colorants.

Component (C) can furthermore also comprise impact modifiers, these are preferably selected from the group consisting of polyolefins, polyolefin copolymers, styrene copolymers, styrene block copolymers, ionic ethylene copolymers, it being possible for these to be partially neutralized by metal ions , and mixtures thereof. The impact modifiers are preferably present in functionalized form. The polyamide molding compositions (FM) preferably contain 0 to 35% by weight, particularly preferably 5 to 20% by weight, of impact modifiers.

According to a preferred embodiment of the present invention, the impact modifiers of component (C) are functionalized by copolymerization and / or by grafting. For this purpose, a compound selected from the group consisting of unsaturated carboxylic acids, unsaturated carboxylic acid derivatives and mixtures thereof and / or unsaturated glycidyl compounds is particularly preferably used. This is particularly preferably selected from the group consisting of unsaturated carboxylic acid esters, in particular acrylic acid esters and / or methacrylic acid esters, unsaturated carboxylic acid anhydrides, in particular maleic anhydride, glycidyl acrylic acid, glycidyl methacrylic acid, α-ethyl acrylic acid, maleic acid, fumaric acid, itaconic acid, citrauccconic acid, butenic acid and mixtures thereof .

If the functionalization is carried out by copolymerization, the proportion by weight of each individual compound used for the functionalization is preferably in the range from 3 to 25% by weight, particularly preferably from 4 to 20% by weight and particularly preferably from 4.5 to 15% by weight. -%, each based on the total weight of component (C).

If the functionalization takes place by grafting, the weight fraction of each individual compound used for the functionalization is preferably in the range from 0.3 to 2.5% by weight, particularly preferably from 0.4 to 2.0% by weight and particularly preferably from 0.5 to 1.9% by weight. -%, each based on the total weight of component (C).

As impact modifiers are preferably selected polyolefins or polyolefin copolymers from the group consisting of polyethylene, polypropylene, polybutylene, ethylene-α-olefin copolymers, propylene-α-olefin copolymers, ethylene-propylene copolymers, ethylene-propylene Diene copolymers and their mixtures, the α-olefins preferably having 3 to 18 carbon atoms. The α-olefins are particularly preferably selected from the group consisting of propene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene and mixtures thereof. Among the ethylene-α-olefin copolymers, ethylene-propylene copolymers, ethylene-1-butene copolymers or ethylene-propylene-1-butene copolymers are preferred.

The styrene copolymers are preferably styrene copolymers with a comonomer selected from the group consisting of butadiene, isoprene, acrylate and mixtures thereof. The styrene block copolymers are preferably selected from the group consisting of styrene-butadiene-styrene triblock copolymers (SBS), styrene-isoprene-styrene triblock copolymers (SIS), styrene-ethylene / butylene-styrene triblock copolymer (SEBS), styrene-ethylene / Popylene-styrene triblock copolymer (SEPS) and mixtures thereof.

The styrene-ethylene / butylene-styrene triblock copolymers are linear triblock copolymers composed of an ethylene / butylene block and two styrene blocks. The styrene-ethylene / propylene-styrene triblock copolymers are linear triblock copolymers composed of an ethylene / propylene block and two styrene blocks.

The styrene content in the styrene-ethylene / butylene-styrene triblock copolymers or styrene-ethylene / popylene-styrene triblock copolymers is preferably from 20 to 45% by weight, particularly preferably from 25 to 40% by weight and very particularly preferably from 25 to 35% by weight.

The ionic ethylene copolymers are preferably composed of the monomers selected from the group consisting of ethylene, propylene, butylene, acrylic acid, acrylate, methacrylic acid, methacrylate and mixtures thereof, the acid groups being partially neutralized with metal ions, with particular preference being given to ethylene. Methacrylic acid copolymers or ethylene-methacrylic acid-acrylate copolymers in which the acid groups are partially neutralized with metal ions. The metal ions used for neutralization are preferably sodium, zinc, potassium, lithium, magnesium ions and mixtures thereof; sodium, zinc and magnesium ions are particularly preferred.

WAYS OF CARRYING OUT THE INVENTION

Measurement methods:

Relative viscosity (solution viscosity ηrel)

The relative viscosity was determined according to ISO 307 (2007) at 20 ° C. For this purpose, 0.5 g of polymer granules were dissolved in 100 ml of m-cresol; the calculation of the relative viscosity (RV) according to RV = t / t0 was based on Section 11 of the standard.

Constancy of the solution viscosity:

In the batch process, samples were taken at the beginning of the granulation and at the end of the granulation of a batch, the two samples being taken about 40 minutes apart, and the solution viscosity in each case as indicated above and their difference determined. In the continuous process according to the invention, the difference in the solution viscosity of two samples taken 40 minutes apart was determined. The table shows the mean difference in the solution viscosities, determined from five individual determinations.

Number of inclusions per 100 g

To determine the number of inclusions (black spots) per 100 g, the number of those granules which have inclusions is counted in 100 g of granules. The stated number of inclusions per 100 g is an average of 5 individual determinations. The batch method (comparative examples) is an average of 5 successive batches (each batch provides approx. 4 kg of polyamide), while the continuous method evaluated 5 slots of 4 kg each. This means that a granulate sample of 100 g was taken from each batch or slot and the number of inclusions was counted.

Foil note

To determine the film grade, a flat film with a film thickness of 70 μm was extruded from the polyamides produced in the examples, for example with a Plasti-Corder from Brabender, which was guided past an optical system (CCD camera) which removed the impurities Detect and count in the film (information per m <2>) and determine its size. Such an optical system with an evaluation program is sold by the company OCS GmbH Witten under the name “Foil test FT4”. For the evaluation, the impurities in this film were divided into 10 size classes according to their diameter (see table below) and weighted with different weight factors. To determine the film grade, approx. 1.5 m 2 film was examined. <100 0.1 500 - 600 40 100 - 200 1 600 - 700 55 200 - 300 10 700 - 800 100 300 - 400 20 800 - 900 200 400 - 500 30> 900 350

The film grade was calculated using the following formula by adding the sums of the weighted impurities per size class and dividing by 1000, where xi stands for the impurities per square meter and size class and fi stands for the weight factors:

Color (ΔE)

The E value (color locus) in accordance with EN ISO 11664-4 in the CIELAB color space of the various samples and the respective reference was determined on plates 50 × 40 × 3 mm. For this purpose, the CIE L <*>, a <*>, and b <*> values were determined on a spectrophotometer from Datacolor (device designation: Datacolor 650) under the following measuring conditions in front of a white lacquered contrasting sheet, measuring mode: reflection, measuring geometry: D. / 8 °, type of light: D6510, gloss: included, calibration: UV-calibrated, aperture: SAV (Small Area View, 9 mm illuminated, 5 mm measured). From the L <*>, a <*>, and b <*> values of reference and sample according to the CIELAB system, the color difference ΔE between the color locations (L <*> a <*> b <*>) reference and (L <*> a <*> b <*>) Test according to ISO 12647 and ISO 13655 as Euclidean distance as follows:

As a reference, selected samples made of a polyamide with the same chemical structure as in the respective example or comparative example, produced according to the batch process on a 5 t production facility, were used. For example, a selected sample of polyamide MACM12, produced on a batch production facility, was used as a reference for example B1 and comparative example CE1.

End groups (amino and carboxy end groups)

The amino (NH2) and carboxy (COOH) end group concentrations are determined by means of a potentiometric titration. For the amino end groups, 0.2 to 1.0 g of polyamide are dissolved in a mixture of 50 ml of m-cresol and 25 ml of isopropanol at 50 to 90 ° C. and, after addition of aminocaproic acid, titrated with a 0.05 molar perchloric acid solution. To determine the COOH end groups, 0.2 to 1.0 g of the sample to be determined, depending on its solubility, is dissolved in benzyl alcohol or a mixture of o-cresol and benzyl alcohol at 100 ° C and, after adding benzoic acid, titrated with a 0.1 molar tetra-n-butylammonium hydroxide solution.

Example B1: Production of an amorphous polyamide based on MACM and 1,12-dodecanedioic acid (process according to the invention)

MACM was stored in a storage container at 80 ° C. and the mixture of 1,12-dodecanedioic acid and benzoic acid at 140 ° C. under inert gas. The hypophosphorous acid was mixed with water in a ratio according to Table 1 and stored at 23 ° C. in a tank under an inert gas. The starting materials (MACM, mixture of dodecanedioic acid and benzoic acid, mixture of hypophosphorous acid and water) were continuously conveyed into the reactor of the first oligomerization zone (tubular reactor, length: 1400 mm, diameter: 32 mm, with static mixer) via separate heaters, so that the The temperature of the individual components was 170 ° C. (T0) in each case before entry into the tubular reactor of the first oligomerization zone. The reaction mixture was then heated to a temperature T1 of 210 ° C. in the reactor. The pressure was set to 25 bar (P1). The reaction mixture was then transferred via a valve into the second oligomerization zone (tubular reactor, length: 2000 mm, diameter: 25 mm, with 3L receiver) and there was let down to a pressure of 10 bar (P2). At the same time, the temperature of the reaction mixture was increased to 248 ° C. (T2) and the water in the gas phase was separated off. The liquid reaction mixture was then introduced into the post-condensation zone (tubular reactor, length: 1000 mm, diameter: 32 mm) via a further valve, with a second expansion step taking place. The pressure in this zone was reduced to atmospheric pressure (P3 = 1 bar) and the temperature was increased to 295 ° C (T3). After transferring the reaction mixture into the discharge unit, designed as a twin-screw extruder (Leistritz Micro, screw diameter: 27 mm / length: 44D) with cylinder temperatures (T4) in the range from 250 to 280 ° C, the water released in the post-condensation zone was separated off by means of a backward degassing, the liquid polymer is discharged as a strand, cooled in a water bath and granulated. The drying took place over a period of 24 hours at 80.degree. 4.0 kg of MACM12 polyamide were produced per hour. The diamine to dicarboxylic acid molar ratio was 1.02.

Table 1: Dosage of the starting materials for example B1

MACM 2'214 45.98 DDS 2'094 43.50 Benzoic acid 22.76 0.47 Water 481.4 10.00 Hypophosphorous acid 2.276 0.047

Example B2: Production of a microcrystalline polyamide based on PACM and 1,12-dodecanedioic acid (process according to the invention)

The test procedure corresponded to Example 1, with the difference that not the diamine MACM but the diamine PACM was used and the delivery rates were selected according to Table 2 and the temperature T1 was 215 ° C. and the pressure P1 was 26 bar. 3.8 kg of microcrystalline polyamide PACM12 were produced per hour. The amount of water added was 8% by weight based on the total batch and the molar ratio of diamine to dicarboxylic acid was 1.01.

Table 2: Dosage of the starting materials for example B2

PACM 1,984 44,100 DDS 2,155 47,895 benzoic acid 0 0 water 360.0 8,000 hypophosphorous acid 0.206 0.005

Example B3: Production of a microcrystalline polyamide based on PACM, MACM and 1, 12-dodecanedioic acid (process according to the invention)

The experimental procedure corresponded to Example 1, with the difference that it was not the diamine MACM alone, but a 1: 1 mixture of the diamines MACM and PACM in terms of molar proportions, and the delivery rates were selected in accordance with Table 3. The production rate was 3.6 kg of microcrystalline polyamide MACM12 / PACM12 per hour. The amount of water added was 6% by weight based on the total batch and the molar ratio of diamine to dicarboxylic acid was 1.01.

Table 3: Dosage of the starting materials for example B3

MACM 989.7 24.82 PACM 869.6 21.80 DDS 1,833 47.22 Benzoic acid 5,377 0.13 Water 239.3 6.00 Hypophosphorous acid 0.967 0.024

Comparative example CE1: Production of an amorphous polyamide based on MACM and 1, 12-dodecanedioic acid (batch process)

A pressure autoclave of 20 L capacity was charged with 2,356 g 1,12-dodecanedioic acid, 2,491 g MACM, 5,122 g 50% aqueous hypophosphorous acid (H3PO2), 25.61 g benzoic acid and 1,625 g water. After inerting with nitrogen, the autoclave was first heated to 200 ° C. and stirred until a homogeneous solution was obtained. The temperature was then increased to 290 ° C. After a two-hour pressure phase at 290 ° C., the pressure was released to atmospheric pressure within 1.5 hours and degassed at 280 ° C. for about 1 hour. The material was then discharged in strands, cooled in a water bath, granulated and dried at 80 ° C. for 24 hours. The amount of water added was 25% by weight based on the total batch and the molar ratio of diamine to dicarboxylic acid was 1.02.

Comparative example CE2: Production of a microcrystalline polyamide based on PACM and 1, 12-dodecanedioic acid (batch process)

A pressure autoclave with a capacity of 20 L was charged with 2,382 g 1,12-dodecanedioic acid, 2,193 g PACM, 0.456 g 50% aqueous hypophosphorous acid (H3PO2) and 3,654 g water. After inerting with nitrogen, the autoclave was first heated to 170 ° C. and stirred until a homogeneous solution was obtained. The temperature was then increased to 280 ° C. and this temperature was maintained for two hours (pressure phase). The pressure was then released to atmospheric pressure within 1.5 hours and the mixture was degassed at 280 ° C. for about 1 hour. Finally, the material was discharged in strands, cooled in a water bath, granulated and dried at 80 ° C. for 24 hours. The amount of water added was 44% by weight based on the total batch and the molar ratio of diamine to dicarboxylic acid was 1.01.

Comparative example CE3: Production of a microcrystalline polyamide based on PACM, MACM and 1, 12-dodecanedioic acid (batch process)

1,100 g MACM, 966.2 g PACM, 2,092 g 1,12-dodecanedioic acid, 5,974 g benzoic acid, 1,074 g hypophosphorous acid (H3PO2) and 4,165 g soft water were placed in a 20 L pressure autoclave. The autoclave was then closed and heated to 290 ° C. with stirring. After a two-hour pressure phase, the pressure was released to atmospheric pressure within 1.5 hours and degassed at 280 ° C. for about 1 hour. The material was then discharged in strands, cooled in a water bath, granulated and dried at 80 ° C. for 24 hours. The amount of water added was 50% by weight based on the total batch and the molar ratio of diamine to dicarboxylic acid was 1.01. The two diamines MACM and PACM were present in a molar ratio of 50:50 (mol%).

The respective comparison of B1 with VB1, B2 with VB2 and B3 with VB3 (Table 4) clearly shows that the production process according to the invention produces products with significantly fewer inclusions, a better film grade and a lower inherent color. In addition, the products have a high degree of constancy in the solution viscosity. The method according to the invention is therefore suitable for producing amorphous or microcrystalline polyamides with a significantly improved quality. Furthermore, the continuous process is energy efficient, since much less water has to be removed from the reaction mixture by evaporation.

Table 4: Results

Solution viscosity (ηrel) - 1.69 1.72 1.71 1.70 1.71 1.71 End groups COOH mmol / kg 70 65 72 75 68 72 NH2 mmol / kg 66 63 68 76 71 70 Constancy of the solution viscosity - 0.01 0.01 0.01 0.04 0.03 0.03 Number of inclusions per 100 g - 2 3 2 14 25 18 Foil grade - 0.12 0.15 0.08 0.25 0.27 0.28 Color (ΔE) - 0.48 0.24 0.13 0.97 1.23 1.18

Claims (15)

1. A process for the continuous production of amorphous or microcrystalline polyamides A based on cycloaliphatic diamines and aliphatic dicarboxylic acids, comprising the steps: a The monomers present in the melt state, comprising the at least one cycloaliphatic diamine Y and the at least one acyclic aliphatic dicarboxylic acid X, and optionally further diamines V and aminocarboxylic acids Z, and water W are continuously fed into a first oligomerization zone separately at a temperature T0 without premixing fed in, the amount of water, based on the weight of all starting materials for producing the polyamide A, being at most 20% by weight; Optionally, monofunctional regulators S, catalysts K and processing aids U in the melt state or dissolved / dispersed in water are also fed to the first oligomerization zone; b The composition fed in in stage a is subjected to an oligomerization in a first oligomerization zone without mass transfer with the environment at a temperature T1 and a pressure P1; c The reaction mixture from stage b is transferred to a second oligomerization zone and there the oligomerization is continued at a temperature T2 and a pressure P2, part of the water being separated off via the vapor phase and where T2> T1 and P2 <P1; d The reaction mixture from stage c is transferred to a post-condensation zone and further condensed there at a temperature T3 and a pressure P3 with the release of water, where T3 ≥ T2 and P3 <P2 and a liquid-gaseous reaction mixture is formed; e The reaction mixture from stage d is fed to a discharge zone which operates in a temperature range T4, where the liquid polyamide (A) in the melt, after separation of the gas phase, is compacted, optionally further degassed, discharged and, after cooling, granulated. 2. A process for the continuous production of a molding compound FM, containing at least one amorphous or microcrystalline polyamide A, comprising the steps: a The monomers present in the melt state, comprising the at least one cycloaliphatic diamine Y and the at least one acyclic aliphatic dicarboxylic acid X, and optionally further diamines V and aminocarboxylic acids Z, and water W are continuously fed into a first oligomerization zone separately at a temperature T0 without premixing fed in, the amount of water, based on the weight of all starting materials for producing the polyamide A, being at most 20% by weight; Optionally, monofunctional regulators S, catalysts K and processing aids U in the melt state or dissolved / dispersed in water are also fed to the first oligomerization zone; b The composition fed in in stage a is subjected to an oligomerization in a first oligomerization zone without mass transfer with the environment at a temperature T1 and a pressure P1; c The reaction mixture from stage b is transferred to a second oligomerization zone and there the oligomerization is continued at a temperature T2 and a pressure P2, part of the water being separated off via the vapor phase and where T2> T1 and P2 <P1; d The reaction mixture from stage c is transferred to a post-condensation zone and further condensed there at a temperature T3 and a pressure P3 with the release of water, where T3 ≥ T2 and P3 <P2 and a liquid-gaseous reaction mixture is formed; e The reaction mixture from stage d is fed to a discharge zone which operates in a temperature range T4, where the liquid polyamide A in the melt, after separation of the gas phase, compacted, mixed with fillers B and / or additives C, optionally further degassed, discharged and granulated after cooling. 3. The method according to any one of the preceding claims, wherein the amount of water is less than 15 wt .-%, preferably 2 to 12 wt .-%, particularly preferably 4 to 10 wt .-%, each based on the weight of all starting materials for the preparation of the Polyamide (A). 4. The method according to any one of the preceding claims, wherein the monofunctional regulator S is selected from the group consisting of monocarboxylic acids S1: formic acid, acetic acid, propionic acid, n-, iso- or tert-butyric acid, valeric acid, trimethylacetic acid, caproic acid, enanthic acid, caprylic acid , Pelargonic acid, capric acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, pivalic acid, cyclohexanecarboxylic acid, benzoic acid, methylbenzoic acids, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, phenylacetic acid, methacrylic acid, acrylic acid, acrylic acid, linucic acid, ericic acid, linucic acid, linucic acid, and acrylic acid mixtures from that; or monoamines S2: methylamine, ethylamine, propylamine, butylamine, hexylamine, heptylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, cyclohexylamine, dicyclohexylamine and mixtures thereof. 5. The method according to any one of the preceding claims, wherein the catalyst K is selected from the group consisting of: phosphoric acid, phosphorous acid, hypophosphorous acid, phenylphosphonic acid, phenylphosphinic acid and / or their salts with mono- to trivalent cations. 6. The method according to any one of the preceding claims, wherein at least one of the temperature or pressure ranges mentioned below is selected, preferably all ranges are selected at the same time: the temperature T0 is in the range from 130 to 200 ° C .; the temperature T1 is in the range from 190 to 230 ° C; the temperature T2 is in the range from 240 to 270 ° C; the temperature T3 is in the range from 260 to 320 ° C; the temperature T4 is in the range from 240 to 300 ° C; the pressure P1 is in the range from 20 to 50 bar; the pressure P2 is in the range from 5 to 15 bar; the pressure P3 is in the range from 1 to 4 bar. 7. The method according to any one of the preceding claims, wherein the amorphous or microcrystalline polyamide A is a polyamide of the formula VX / YX / Z, where at least the polyamide unit YX must be present and where the monomer units V, Y, X and Z are derived from the following molecules which are present in amidic bond in the polyamide A: V: Acyclic aliphatic diamine with preferably 4 to 12 carbon atoms; Y: cycloaliphatic diamine; X: Acyclic aliphatic dicarboxylic acid having 6 to 18 carbon atoms; Z: aminocarboxylic acids. 8. The method according to any one of the preceding claims, wherein the amorphous or microcrystalline polyamide A is selected from the group consisting of MACM6, MACM8, MACM9, MACM10, MACM12, MACM14, MACM16, MACM18, PACM6, PACM8, PACM9, PACM10, PACM12, PACM14 , PACM16, PACM18, TMDC6, TMDC8, TMDC9, TMDC10, TMDC12, TMDC14, TMDC16, TMDC18, MACM10 / PACM10, MACM12 / PACM12, MACM14 / PACM14, MACM16 / PACM16, MACM18 / PACM18, TMDC10 / P12 / PACM10 / PACM14, TMDC16 / PACM16, TMDC18 / PACM18, MACM10 / MACM12, MACM10 / MACM16, MACM12 / MACM16, PACM10 / PACM12, PACM10 / PACM16 and PACM12 / PACM16. 9. The method according to any one of the preceding claims, wherein the amorphous or microcrystalline polyamide A is selected from the group consisting of MACM10, MACM12, MACM14, MACM16, PACM10, PACM12, PACM14, PACM16, TMDC10, TMDC12, TMDC14, TMDC16, MACM10 / PACM10 , MACM12 / PACM12, MACM14 / PACM14, MACM16 / PACM16, MACM10 / MACM12, MACM10 / MACM16, MACM12 / MACM16, PACM10 / PACM12, PACM10 / PACM16 and PACM12 / PACM16. 10. The method according to any one of the preceding claims, wherein the amorphous or microcrystalline polyamide A is selected from the group consisting of the polyamides MACM12, PACM12 and MACM12 / PACM12. 11. Polyamide produced by the process according to any one of claims 1 and 3-10. 12. Polyamide according to claim 11, characterized in that the polyamide has a solution viscosity, determined on the basis of a solution of 0.5 g of polymer dissolved in 100 ml of m-cresol at 20 ° C according to ISO 307: 2007, in the range of ηrel = 1.4 to 2.5, preferably in the range from ηrel = 1.5 to 2.0, in particular in the range from 1.55 to 1.90. 13. Polyamide molding compound produced by the process according to one of claims 2 to 10, characterized in that the polyamide molding compound FM contains the following components or consists of the following components: A 25 to 100% by weight of amorphous or microcrystalline polyamide B 0 to 70% by weight of at least one filler C 0.01 to 30% by weight of at least one additive different from A and B, components A to C totaling 100% by weight. 14. Use of the amorphous or microcrystalline polyamides A, produced according to the process according to one of Claims 1 and 3 to 10, for producing components in the fields of electrical / electronics, automobiles and optics. 15. Use of the polyamide molding compound FM, produced according to the method according to any one of claims 2 to 10, for the production of components in the fields of electrical / electronics, automotive and optical applications.