TWI648310B - Process for the preparation of a polyamide - Google Patents

Abstract

The present invention relates to a process for the preparation of a semi-aromatic polyamine from a diamine and a dicarboxylic acid, which comprises the steps of: (i) dispensing a liquid or gaseous diamine to an aromatic dicarboxylic acid-containing process. The powder is stirred to form a powder containing a diamine/dicarboxylate (DD-salt), and (ii) the DD-salt is polymerized in a solid state to obtain the polyamine.

Description

Preparation method of polyamine

The present invention relates to a process for the preparation of polyamines (so-called AA-BB polyamides) from diamines and dicarboxylic acids, and more particularly to the preparation of semi-crystalline semi-aromatic AA-BBs. The method of polyamine. The invention also relates to products obtained by this method.

There are various methods for preparing polyamines. Known methods include melt polymerization, solution polymerization, suspension polymerization, solid state polymerization, and the like. Polyamines made from diamines and dicarboxylic acids are usually prepared by condensing the diamine and dicarboxylic acid in a molten state. However, this procedure is not suitable for polyamines which are more heat sensitive and have a higher melting point because they cause side reactions of degradation of such polymers. Therefore, there is interest in low temperature processes for the preparation thereof, such as solid state polymerization, which is abbreviated as SSP herein.

A well-known and widely used method for preparing polyamines is a multi-step process containing SSP as another step. Examples thereof include a method in which a prepolymer is in an aqueous solution, in a suspension in an inert liquid, or in a melt, in the first step. The prepolymer thus formed is isolated from the solution or suspension and cured or cured directly from the melt and, while still in a solid state, further polymerized to produce a higher molecular weight polymer. Such a method of further subjecting the solid prepolymer to polymerization is also referred to as solid post-condensation or solid-state finishing, and is abbreviated herein as post-SSP.

In the case of AA-BB polyamide, a solid state polymerization method is also known in which a salt of a diamine and a dicarboxylic acid, which is in the form of a powder, is directly polymerized to form a polymer having a desired molecular weight. Amidoxime polymer. This salt powder solid state polymerization is also referred to as direct solid state polymerization, which is abbreviated herein as direct SSP.

Solid state polymerization processes (for polyamines, post-SSP and direct SSP) are also described in the book "Solid-state Polymerization" by C.D. Papaspyrides and S.N. Vouyiouka, Wiley, 2009.

One of the problems with low temperature processes is the long reaction time, which is typically solved by the use of a catalyst to accelerate the condensation reaction. Long reaction times are also a problem in the melt polymerization, in which a phosphorus-containing catalyst is usually used. The necessity of adding a catalyst within the solid state polymerization process has also been previously confirmed. According to R. Pfaender's description in the book "Solid-state Polymerization" (by. CDPapaspyrides and SNVouyiouka, Wiley, 2009, p. 167), the reaction rate of the solid process is not high enough and significantly lower than The reaction rate of a similar melt or solvent process. Known reactivity problems are more pronounced due to the use of aromatic dicarboxylic acids such as citric acid and isononanoic acid, such as, for example, in the paper "The condensation Kinetics of Polyphthalamides: I. Diamines and Diacids of Dimethylesters" ( Done by Malluche J.; Hellmann, GP; Hewel M.; Liedloff, HJ; Polym. Eng. Sci. 2007, 47, 1589), known, etc. It is less reactive than an aliphatic dicarboxylic acid such as adipic acid.

Examples of patents relating to the SSP and direct SPP methods for polyamines are as follows.

JP-62020527-A2 describes a process for preparing polyamido-6T starting from a first-order molar concentration of 1,6-hexanediamine and a salt of citric acid (abbreviated herein as a 6T salt). The salt is prepared from an aqueous solution which is isolated from the aqueous solution in the form of a solid powder. The polymerization process comprises a suspension polymerization step and a post-SSP step. First, at a high temperature, in the case where nitrogen is foamed therein, a prepolymer is formed in the suspension of the salt in cresol, but the salt is thus not melted. The prepolymer was then isolated and subjected to another polymerization in the presence of sodium hypophosphite as a catalyst under a nitrogen atmosphere. If a sodium hypophosphite catalyst is not used, the polymerization takes a long time and a gelled material is obtained.

No. 4,925,914 describes a suspension polymerization process in which a salt of a diamine and a dicarboxylic acid is dispersed together with a phosphorus-containing catalyst in an inert liquid and polymerized in the form of a suspension, and then the polymer is isolated from the reaction medium. And analyzed. Intensive mixing must be carried out by using a high shear mixer to finely disperse the salt and catalyst in the reaction medium. These examples include various semi-aromatic homopolymers. Typical values for the yield of the formed polymer are in the range of 23% to 76%.

U.S. Patent No. 5,128,442 describes a direct SSP process from a solid salt of one of a diamine and a dicarboxylic acid. In the process of U.S. Patent No. 5,128,442, the solid salt is prepared from a solution, suspension or dispersion containing the dicarboxylic acid and diamine, and a catalytically effective phosphorus compound uniformly distributed therein. The The salt is polymerized in the solid form at a first reaction temperature to form a prepolymer. The prepolymer is further polymerized at a second, higher reaction temperature to form a higher molecular weight polymer. In one example, a semi-aromatic polyamine (PA-6T/66, 50/) having a melting temperature of 302 ° C is formed from a 6T/66 salt obtained from an aqueous solution in the presence of a catalyst. 50 m / m). The polymerization took 33 hours and the resulting polymer had a total number of end groups of 360 to 380 millimoles per kilogram (meq/kg) which corresponded to a molecular weight of only about 3,000 grams per mole. In view of the presence of the catalyst and even a polymer having a lower molecular weight, the reaction time is considered to be still quite long. Further, the use of higher reaction temperatures within the methods of this patent creates problems and is significantly limited by the severe adhesion of solid materials.

The salt process is typically carried out in a solvent or diluent. The salt may first be polymerized into a prepolymer by solution or suspension polymerization in the solvent or diluent, and then isolated as a solid prepolymer, followed by a post-SSP to form the final polymer. Alternatively, the salt is first isolated as a solid powder from the solvent or diluent and polymerized by melt polymerization or solid state polymerization. A further method for the preparation of a salt is described in U.S. Patent Nos. 5,801,278 and 5,874,520, each of which uses a low temperature medium. No. 5,874,520 describes a process in which a solid diamine carbamate is mixed with a solid dicarboxylic acid. These compounds are especially mixed under high shear conditions which exhibit "new" particle surfaces of molecules that have been reacted without frictional friction or the like. The use of a low temperature medium such as dry ice or nitrogen not only controls the heat of the reaction, but also maintains the reaction mixture in a solid state. US-5,801,278 describes in the presence of a cryogenic medium such as dry ice and liquid nitrogen, A process for preparing a diamine/dicarboxylate. US-5,801,278 further clarifies the same process that can be used to form a paste rather than a free flowing powder without the use of a cryogenic medium. The use of organic solvents (such as for suspension polymerization), or low temperature media can complicate the overall process and can result in undesired additional costs, or even hinder mass production. Semi-crystalline semi-aromatic polyamides are high performance thermoplastics, and the high price is partly due to manufacturing costs. It is therefore necessary to optimize the process for equipping such semi-crystalline semi-aromatic AA-BB polyamines to allow for high yield preparations in an efficient manner without gelation.

One object of the present invention is an optimized process for the preparation of semi-crystalline semi-aromatic polyamines. The object is achieved according to the process of the invention comprising the steps of: (i) dispensing a liquid diamine to a stirred powder comprising an aromatic dicarboxylic acid to form a diamine/dicarboxylate-containing powder. And (ii) subjecting the diamine/dicarboxylate to solid state polymerization to obtain the polyamine.

A direct effect of the process according to the invention is carried out in solid state in all steps and therefore does not melt, dissolve or disperse in a liquid or be cooled by a cryogenic medium. Solvents, dispersants, use of low temperature media, and the like processing and regeneration steps can be omitted, thereby saving processing and energy costs. The semicrystalline semi-aromatic polyamines produced using the process according to the invention did not show signs of gelation and were obtained in high yield.

Polyamines made from diamines and dicarboxylic acids are also known as AA-BB Polyamide. This nomenclature is used in accordance with Nylon Plastics Handbook, Edited by Melvin I. Kohan, Hanser Publishers, 1995; for example, PA-6T means a structured block, a homopolymer of 1,6-hexanediamine and p-nonanoic acid, PA -66/6T represents a copolymer made from 1,6-hexanediamine, adipic acid and p-citric acid, and the blend of PA-66 and PA-6T is called PA-66/PA-6T. .

Figure 1 shows an SEM image of powder particles of semi-crystalline semi-aromatic polyamide produced by the process of the present invention. The powder particles have a size of several hundred microns. The powder particles represent a microporous structure in which pores, cracks, and many small crystallites are visible at the surface. A portion of the second particle can be seen on the left side of the figure.

The term "polyamine" as used herein, unless otherwise expressly indicated, includes both homopolyamine and copolyamine. When more than one diamine and/or more than one dicarboxylic acid is used, the process according to the invention allows the preparation of a copolyamide or a polyamido copolymer, however when only one diamine and one dicarboxylic acid are used, A homopolyamine or a polyamine homopolymer is then formed. The homopolyamines and copolyamines together are also referred to as (co)polyamines.

The terms "diamine" and "dicarboxylic acid" are also intended to be used in the phrase "the semi-aromatic (co)polyamine is selected from the group consisting of diamines and dicarboxylic acids" unless otherwise specified or unambiguously specified. These include diamines containing two or more different diamines, and dicarboxylic acids containing two or more different dicarboxylic acids. For example, in the case of homopolyamines, only one diamine and one dicarboxylic acid are used.

The polyamine obtained by the method is a semi-aromatic polyfluorene amine. The term semi-aromatic as used herein means that the polyamine contains an aromatic group-containing repeating unit different from other repeating units, particularly aliphatic repeating units. More specifically, the semi-aromatic polyamine obtained by this method comprises a repeating unit derived from an aromatic dicarboxylic acid. The aromatic dicarboxylic acid is one in which the carboxylic acid groups (-CO2H groups) are directly attached to the aromatic units and have no methylene or other aliphatic units therebetween.

The term diamine/dicarboxylic acid as used herein means a diammonium dicarboxylate salt obtained by contacting a dicarboxylic acid and a diamine and neutralizing the dicarboxylic acid and the diamine. The abbreviation "diamine/dicarboxylate" is also a DD salt.

In the process according to the invention, the diamine/dicarboxylate is formed by dispensing a diamine to a stirred powder comprising an aromatic dicarboxylic acid. This step is referred to herein as the salt preparation step, or step (i).

The term "stirred powder" as used herein means to maintain moving powder particles. It may, for example, be mechanical, or by air flow, or by gravity, or by any combination thereof, as by stirring in a rotating vessel, stirring by rolling, or by fluidizing in a fluidized bed reactor. Achieved by the role. The DD salt formed is typically in the form of a powder.

By powder herein is meant a particulate material composed of discrete and substantially solid particles. These particles (referred to as powder particles) suitably have a particle size ranging from submicron to about 2 mm or less.

The use of the dicarboxylic acid powder in the salt preparation step (i) in the form of a powder in the form of the salt preparation step (i) means that the stirred powder has a melting temperature below the dicarboxylic acid temperature. The preparation of the DD salt in a stirred powder also means that the temperature of the powder is lower than the DD salt (which is The melting temperature is further referred to herein as "Tm-salt".

During the formulation of the diamine, the temperature of the agitated powder is referred to herein as the term "powder temperature." The temperature of the agitated powder can be determined by standard methods (e.g., using a thermocouple).

The stirred powder comprises at least one aromatic dicarboxylic acid. The chopped powder in step (i) may comprise a mixture of two or more dicarboxylic acids (e.g., two or more aromatic dicarboxylic acids, or one aromatic dicarboxylic acid and one aliphatic dicarboxylic acid). When the dicarboxylic acid powder is composed of two or more dicarboxylic acids, and wherein the dicarboxylic acid powder is composed of a physical state mixture of one or more dicarboxylic acid powders, the salt preparation step (i) is equally likely A mixture of physical states of 2 or more DD salts is obtained. In this case, the powder temperature should be lower than the lowest temperature of the melting temperature of the DD salt having the lowest melting temperature and the lowest temperature of the melting temperature of the dicarboxylic acid having the lowest melting temperature.

In step (i), the diamine is distributed to the stirred powder in the form of a liquid. In the case where the diamine is a solid at room temperature, it may be necessary to first melt the diamine for the preparation of the liquid diamine.

Once the diamine is dispensed, the diamine and the dicarboxylic acid in the form of a stirred powder form a reaction mixture whose composition can be gradually changed. The dicarboxylic acid is originally contained, and after a period of time, the self-mixing dicarboxylic acid The acid and the diamine/dicarboxylate are altered, and finally the diamine/dicarboxylate powder can be formed.

In step (ii) of the process according to the invention, the diamine/dicarboxylate is polymerized in the solid state to produce the polyamine. Preferably, the DD salt is polymerized in the form of the powder from step (i).

The term solid state polymerization in the text means that the DD can be made The polymerization is carried out under conditions in which the salt, the polyamine and any intermediate condensation products thereof maintain the solid state. This is carried out by using the reaction temperature for the condensation step (group) which is lower than the melting temperature of the DD salt, respectively lower than the melting temperature of the polyamine, and any intermediate product thereof.

When the process is not carried out in the solid state, it can result in fusion of the particles to form agglomerates and cohesive powder flow. Once these phenomena occur, the temperature at which the reactants begin to mechanically deform (also known as the softening temperature) depends on the process and process conditions, and is therefore preferably under real life process conditions, such as laboratory scale. The test scale or factory scale is measured. It can be done experimentally at different temperatures, from below the softening temperature to near the softening temperature. In the agitation process equipment, for example, during heating from below the softening temperature to the softening temperature, the softening temperature is expressed as a sharp increase in the measured torque. In the static polymerization experiment, the softening temperature can be observed, for example, from a sample showing agglomerates containing molten and molten particles. In the case of the solid state polymerization in the process according to the present invention, softening is avoided by applying a condensation condition which is much lower than the melting temperature of the intermediate product of the DD salt, polyamine and the like.

Unless otherwise indicated, the term melting temperature (Tm) as used herein means in the context of a DSC according to the method of ISO 11357-1/3 (2009) (the scanning rate in the first heating cycle is 20 ° C / The endothermic melting peak was measured in minutes.

The salt production process in a stirred powder and in its solid state polymerization is carried out in the solid state. It does not exclude the addition or formation of liquid components during the course of the process. First, you can add all two in a liquid form. The amine is used for salt preparation. For example, during the solid state polymerization step (ii), a liquid diamine may also be added. The diamine used in step (i) may contain a little water. During the polymerization, once the amine is reacted with the carboxylic acid group, water may also be formed which may evaporate and condense. During the preparation of the salt, a small amount of water may also be present in the feedstock or formed during the furnishing step. A small amount of water does not become a problem as long as the stirred powder can be maintained. The water may be removed by evaporation during or during the heating of the solid state polymerization during or after the preparation of the salt.

The powder containing the DD salt as prepared in step (i) may comprise water (e.g., about 7.5% by weight, or even higher), such as water for crystallization, and still maintain the form of the agitated powder. The powder preferably comprises up to 5% by weight of water, more preferably up to 2.5% by weight or even more preferably up to 1.0% by weight or 0.5% by weight of water, wherein the % by weight (wt%) is relative to the diamine and dicarboxylic acid In terms of the total weight within the DD salt. In the salt preparation step (i), the diamine is distributed in liquid form. The distribution of the diamine in liquid form during the salt preparation step necessarily means that the diamine is at a distribution temperature (i.e., at the time of dispensing, the temperature of the diamine is higher than the diamine The melting temperature is lower than the boiling temperature of the diamine). The boiling temperature is measured under the pressure conditions used during dispensing.

The diamine may consist of a mixture of two or more diamines. If a diamine mixture is used, the melting temperature, boiling temperature and dispensing temperature of the diamine will depend on the diamine mixture.

For the preparation of the DD salt, the temperature of the powder during dispensing is preferably at least 40 ° C below the melting temperature (Tm salt) of the DD salt, more preferably at least 60 ° C below the Tm salt. By using a powder temperature that is further lower than the Tm salt The potential for premature reaction of the diamine and dicarboxylic acid can be reduced. The powder temperature is also preferably maintained below 220 ° C; more preferably below 180 ° C. Since a fatty dicarboxylic acid is present in the stirred powder, the temperature of the powder is preferably 150 ° C or lower, and more preferably 130 ° C or lower. The powder temperature is also preferably below the boiling temperature of the water. The boiling temperature is determined herein under the pressure conditions applied while the reaction is proceeding. The problem of the cleaned gaseous water to be condensed in the cold spot and the fouling of the powder on such cooling can be reduced by using a lower powder temperature. This lower powder temperature can also be advantageously applied, as is especially the case with aliphatic dicarboxylic acids, in which the low temperature reaction is more readily carried out and the DD salt which adheres to the particles due to the softening action of water.

The powder temperature is also preferably maintained above 0 °C. For water intended to be present in the reaction mixture for the preparation of the salt, it reduces the risk of freezing of the water. The powder temperature is more preferably at least 20 ° C to allow heat to be removed via a stave and does not freeze the components of the wall.

The diamine is distributed to the stirred powder to form a powder reaction mixture while the stirred powder can be stored. Therefore, the diamine is preferably not added together with the dicarboxylic acid and mixed in the stirred powder, otherwise it is not suitable for retaining the stirred powder, and may also cause agglomerated and unhumided portions of the wetted portion. Incomplete neutralization reaction. It complicates and even inhibits the proper mixing and homogenization of such reaction components. It is preferred to limit the rate of distribution to prevent local accumulation of liquid diamine, thereby preventing excessive wetting, local overheating, and premature reaction with water release resulting in excessive adhesion and complication of movement of the bed. This distribution method is preferred and is expressed by the term "gradually assigned".

As an indication, the diamine liquid is preferably gradually distributed over a period of from about 25 minutes to about 36 hours, such as from about 1 to 20 hours, preferably from 2 to 10 hours. As long as the agitated powder can be retained, a shorter dispensing time of less than 25 minutes can be used, for example 20 minutes. However, it may be more difficult, especially when performed on a larger scale. Longer dispensing times greater than 36 hours can be used, such as 48 hours, or longer. However, for economic reasons, this long allocation time is less good.

It is also preferred to use the one of the following average distribution rates to distribute the diamine: 0.05 mole% diamine per minute (mppm) (equivalent to a total distribution time of 33.3 hours) and 5 moles per minute (20 minutes) Between amines (mppm), preferably between 0.1 mppm (16.7 hours) and 4 mppm (25 minutes), such as between 0.2 mppm (8.35 hours) and 2 mppm (50 minutes), or between 0.25 mppm (6.7) Between 1 hour and 1 mppm (100 minutes), wherein the mole % of the diamine is relative to the molar amount of the dicarboxylic acid. The time in parentheses indicates the corresponding allocation time.

Long dispensing times can be used at low dispensing rates, respectively, and allow the amine to react more time with the dicarboxylic acid, and preferably to prevent softening or sticking of the acid or solid DD salt, but it will This method is less economical. However, if appropriate, short dispensing times can be used at higher dispensing rates, respectively, for proper mechanical agitation of the dicarboxylic acid and efficient dispersion of the diamine in the reaction mixture, and removal from the mixing. The heat of the step (which is produced by the formation of a salt of a diamine with a dicarboxylic acid) to prevent adhesion and agglomeration of the reaction mixture may require a more powerful or special mixer design. In each case, a routine experiment can be used, such as the point The appropriate rate of distribution is determined by assigning a variable to the rate.

In another embodiment of the present invention, the salt preparation step (i) comprises contacting the diamine with a dicarboxylic acid to obtain a reaction mixture, wherein the diamine is reacted with the dicarboxylic acid to form a diamine/dicarboxylic acid. a salt, wherein: (a) the dicarboxylic acid comprises an aromatic dicarboxylic acid; (b) the dicarboxylic acid is provided in powder form; (c) the diamine is provided in liquid form; (d) Dissolving the diamine liquid to the dicarboxylic acid powder and maintaining the dicarboxylic acid powder in a constant movement to carry out the contacting step; (e) maintaining the reaction mixture to maintain a constant movement directly after the partitioning is completed, taking a period of time; (d) and (e) at a temperature above 0 ° C and below all temperatures: boiling temperature of the diamine and the dicarboxylic acid, the diamine/dicarboxylate and any intermediate reaction product The melting temperature; and (g) in (d) and (e), the reaction mixture contains up to 5% by weight water relative to the total weight of the amine and dicarboxylic acid.

The utility of this embodiment of the method according to the invention is such that the DD salt obtained is in the form of substantially anhydrous solid particles. "Substantially anhydrous", as used herein, means that the DD salt typically contains no more than 5% by weight water relative to the total weight. The DD salt recovered from the process is a stable, substantially free flowing powder. The DD salt obtained is in the form of a generally homogeneous product suitable for use in the general commercial process for preparing polyamine polymers. This result can be obtained without the need for a precipitation step involving the use of an organic solvent and without the use of a low temperature medium in the reaction mixture. This method does not require high shear The mixing step is cut and the method can be easily adjusted to an industrial scale.

For example, if less than one equivalent of a diamine is used, the DD salt may still contain a small amount of unreacted dicarboxylic acid. For example, if more than one equivalent of a diamine is used, the DD salt may also contain a small amount of unreacted diamine. It has been found that the DD salt can contain a small excess of diamine and still exhibit the characteristics of a dry solid powder.

The DD salt formed in step (i) may be a salt of the first molar concentration, but is not necessarily a first molar concentration salt. Even when using (close to) a stoichiometric amount of a diamine and a dicarboxylic acid, as evidenced by X-ray diffraction (XRD) measurements for the aromatic dicarboxylic acid, and for use in the DD salt The gas chromatographic analysis of the headspace sampler of the diamine allows analysis of the unreacted dicarboxylic acid and the unreacted diamine to be present simultaneously in the DD salt. Unexpectedly, it does not appear to have a significant effect on the solid state polymerization, since these reactants can be found mainly in the remaining steps of the process, and as evidenced by XRD, will form almost no residual dicarboxylic acid. And has a relatively high molecular weight or viscosity of the product.

It has further been found that in the case of a diamine excess, the molar balance is at least partially corrected by evaporation of the diamine during the first part of the condensation reaction or during the step (ii-a), however, the dicarboxylic acid is excessive. In particular, the molar balance can be corrected by adding a diamine during this step during the second part of the condensation reaction or step (ii-a) of the process.

It has been found that in the case of salt preparation in which the diamine is very deficient (for example, using a molar ratio of about 0.75 to 0.85 diamine/dicarboxylic acid molar ratio), the diamine can still be modified by adding an excess of the diamine during the solid phase polymerization. Lack and obtain a polyamine having a sufficiently high molecular weight. Therefore, in the methods according to the invention The solid DD salt preferably has a diamine/dicarboxylic acid molar ratio of at least 0.75. The diamine/dicarboxylic acid moie is preferably in the range of 0.75-1.10, more preferably 0.90-1.10, still more preferably 0.95-1.05, and most preferably 0.98-1.02. The advantage of using a diamine/dicarboxylic acid molar ratio closer to 1 is used in a more efficient manner.

The salt preparation step (i) can be carried out in different ways and in different types of reactors. Preferably, the diamine is contacted with the dicarboxylic acid by spraying or dripping the diamine onto the active dicarboxylic acid powder. In a batch operation, it is preferred to spray or drip the diamine onto the active dicarboxylic acid powder, and then, after the diamine has been added, the diamine is sprayed or dropped into the active formed DD salt. The diamine is contacted with a dicarboxylic acid by a mixture with a dicarboxylic acid powder. Suitable reactors wherein the diamine and dicarboxylic acid can be contacted and mixed are, for example, tumble mixers, plowshare mixers, conical mixers, planetary screw mixers and fluidized bed reactors. These mixers are examples of low shear mixers. Although high shear mixers can also be used in principle, based on higher energy consumption, additional cooling requirements of the reaction mixture, wear of over-humidified parts and possible increased cohesion, so high shear mixers Not good. Further information on these and other low shear mixer installations can be found below: "Handbook of Industrial Mixing-Science and" edited by Paul, Edward L.; Atiemo-Obeng, Victor A.; Kresta, Suzanne M. Practice" (Publisher: John Wiley &Sons;2004;; ISBN: 978-0-471-26919-9; Electronic ISBN: 978-1-60119-414-5), in more detail, in Chapter 15, Part 15.4 and Within 15.11.

The temperature within the reactor can be controlled by conventional methods. Removable once the diamine is neutralized with the dicarboxylic acid to form the diamine/dicarboxyl The heat generated during the acid salt. For the removal step, a conventional method such as a heat exchanger, a cold wall, a cold agitator, or a combination of a gas stream or the like can be used.

The salt formation reaction itself appears to be fast enough, thus also allowing continuous salt manufacture in a suitable apparatus in a cost effective manner. For example, the process can be carried out in a continuous operation by means of an auxiliary dispensing device around a continuous feed mixing screw in a tube or tank to prepare the salt, preferably by spraying the diamine in a mixing zone or The diamine is contacted with the dicarboxylic acid by dropping it onto the stirred dicarboxylic acid powder.

The fact that the salt preparation step in the process according to the invention can be carried out without using high shear and still achieve a high degree of conversion is surprising. In fact, to avoid abrasion of the dicarboxylic acid powder, low shear agitation can be used to produce a stirred powder. In fact, the attrition can be very low, or even completely absent, so that the particle size distribution is hardly affected, unlike the fact that the size of the dicarboxylic acid powder particles generally increases during the reaction with the diamine. The advantage of this low shear agitation under the unavailability of the dicarboxylic acid powder is that the amount of fine particles produced during the process is low, and that fouling, fine dust, sagging self-weight upon storage, and due to minute particles The problem of reduced fluidity of plugging is reduced.

The dicarboxylic acid powder used in the process according to the invention preferably comprises a small fraction of particles having a small particle size. The dicarboxylic acid powder also preferably has a narrow particle size distribution. For example, the dicarboxylic acid powder has a particle size distribution having a d10 of at least 15 microns and a d90 of at most 1000 microns. Herein, the particle size distribution is determined by laser granulometry according to the method of ISO 13320 at 20 °C. a dicarboxylic acid powder having a small fraction of small particles and/or a narrow particle size distribution It is preferably used and stirred with low shear. The advantage is that the DD salt thus produced also has fewer small particles, each having a rather narrow particle size distribution, and optionally, even better flow properties.

The d10 of the particle size distribution of the dicarboxylic acid powder is preferably in the range of from 15 to 200 μm, more preferably in the range of from 16 to 160 μm. The d90 is preferably in the range of from 100 to 1000 microns, more preferably in the range of from 150 to 800 microns. The dicarboxylic acid powder preferably also has a particle size (d50) in the range of from 40 to 500 μm. The d50 is preferably in the range of 40 to 400 microns. The dicarboxylic acid powder also preferably has a Span (span) particle size distribution of from one to five, which is defined by the ratio of (d84-d16) / d50. This advantage also has a narrower particle size distribution in the formed DD salt and this flow rate is further improved.

The reaction is started by using a dicarboxylic acid powder having a narrow particle size distribution, and a low shear mixing step is applied to obtain a salt powder having good flowability.

The solid DD salt preferably has a flowability (ffc) of at least 4 (more preferably at least 7). This flowability is defined herein as the ratio of the consolidation stress (σ1) to the unrestricted relief strength (σc) (σ1/σc), which is determined by the shear test method according to ASTM D6773. In a particular embodiment of the invention, the solid DD powder is a free flowing powder, i.e., has a flowability (ffc) of at least 10. The salt powder having such good flowability can be more easily obtained by starting the reaction using at least 50 mol% of the aromatic dicarboxylic acid, wherein the molar % is relative to the total number of molars of the dicarboxylic acid in the powder bed. meter. The remainder of the dicarboxylic acid can be a fatty acid dicarboxylic acid. If a fatty acid diamine is used in combination, the salt powder formed contains an aromatic DD salt and an aliphatic DD salt. The DD Preferably, the salt is predominantly an aromatic dicarboxylic acid, i.e., the DD salt from the powder of step (i) consists of an aromatic DD salt.

In another particular embodiment, the solid DD salt powder has a particle size distribution of at least 20 micrometers (μm) of d10, and at most 1000 micrometers of d90, as determined according to ISO 13320. Preferably, the particles have a medium particle size (d50) in the range of from 50 to 600 microns. The solid DD salt preferably has a particle size distribution wherein the d10 is in the range of 20-200 microns, the d50 is in the range of 50-500 microns, and the d90 is in the range of 200-1000 microns. The DD salt also preferably has a particle size distribution of one to five (preferably up to 2.5) Span, which is defined as the ratio of (d84-d16) / d50. Salts having such a particle size distribution can be obtained from dicarboxylic acids having a relatively narrow particle size distribution and small amounts of fine particles and using the above-described low shear mixer.

The solid DD salt powder also preferably has a compression ratio of up to 35%, expressed as a ratio of (TBD-ABD) / TBD * 100%, wherein ABD is the overall density of the charge, and TBD is the overall density of the fill, These are all determined by the method according to ASTM D6393.

Since the solid DD salt between step (i) and step (ii) as described below is not further shaped, as in the method described in claim 1, the low content and the narrowness of each of the fine particles are Particle size distribution, high flow and low compression properties are advantageous.

The solid DD salt obtained by the step (i) is a polycrystalline salt powder composed of powder particles containing polycrystallites. The salt typically has a relatively large surface area compared to the size of the powder particles. The DD salt powder may advantageously have a high BET value of at least 0.5 m ² /g, or more specifically, at least 0.8 m ² /g. Herein, the BET value is determined by the method according to ISO 9277:2010.

The salt preparation step (i) and the polymerization step (ii) in the process according to the invention may be carried out in a single reactor or in separate reactors.

In a preferred embodiment, the solid DD salt is prepared in step (i) and the polymerization step (ii) is carried out in a single process in a single reactor. The advantage is that the number of processing steps can be reduced. Another advantage is that if the salt is made at a high temperature, energy can be saved by omitting the cooling of the salt after step (i) and reheating for step (ii).

Alternatively, after the salt is prepared, the salt can be transferred from a first reactor (referred to as a furnish/mix reactor) to another reactor (the polymerization reactor).

In a particular embodiment, the DD salt is subjected to a solid forming step and the salt is then subjected to a polymerization step (ii). By using a solid state forming step, the salt can retain its polycrystalline structure containing multiple crystallites or substantially multiple crystallites. Within the solid forming step, the salt powder can, for example, be granulated to form granules, or compacted into small pieces. Also, polyamines obtained from the condensation step, respectively, in the form of granules or tablets are obtained.

It may be advantageous to use a solid state forming step in a batch process, or a continuous process using moving column packing, in a static bed reactor (such as static column packing) to further carry out the processing of the solid state polymerization reaction, and further use in the downstream use. The polymer is subjected to a molten state process. The advantage of larger particles within the process is to reduce the use of any gas within the process (although it is used to heat the reaction water, purge gases or gases of each of the reactants) powder. An advantage after the reaction is that the flow properties for processing in silos and large bags can be improved, and the feeding of the melt extruder for subsequent processing of the thermoplastic polymer can be performed more easily and with high capacity.

Granulation can be carried out by spraying a binder onto the powder and keeping the powder active, which is achieved by application, for example, fluidized bed granulation, high shear granulation or drum granulation. Granulation can be carried out, for example, by a gear granulation method, a roller compaction method, a tableting method, or a solid phase extraction method. Examples of such methods can be found in the following materials: the Handbook of Powder Technology, vol. 11 Granulation, Edited by A. D. Salman, M. J. Hounslow, J. P. K. Seville, Elsevier © 2007, ISBN 978-0-444-51871-2. Within each of the methods, a mixture of water, amine or salt solution or the like may be suitable as a binder since these materials do not introduce foreign chemicals into the polymerization mixture. Other suitable binders such as polyvinylpyrrolidone (PVP), polyethylene glycol (PEG), and polyvinyl alcohol (PVA) are not excluded. Typically, less than a weight percent (e.g., 1 to 5% by weight) of binder is used relative to the weight of the powder.

The size of the granules and tablets is typically greater than the powder particles, and thus each of the granules and tablets may comprise a plurality of powder granules. The particles may have a particle size of from about submillimeter to centimeter scale, typically from about 0.5 mm to 4 cm, such as from about 2 mm to about 2 cm. Preferably, the dice may have a maximum diameter of one or less: a few millimeters, such as from about 1 to 8 millimeters, such as from about 2 to about 5 millimeters. Preferably, the tablets may have a particle size ranging from millimeters to centimeters, typically from about 1 mm to 1 cm, such as from about 2 to 5 mm.

In the method of the present invention, the solid DD-salt is solidified Polymerization is carried out to obtain the polyamine. The solid state polymerization can be carried out using known conditions suitable for the direct solid state polymerization of polyamine.

From the beginning to the end of the condensation step, the condensation temperature in step (ii) is maintained at least initially and at least below the melting temperature (Tm-salt) of the DD-salt. The condensation temperature herein is preferably at least 10 ° C below the Tm-salt, preferably at least 15 ° C, more preferably at least 20 ° C below the Tm-salt.

According to a first preferred aspect of the invention, step (ii) comprises a two-step process: (ii-a) at a first condensation temperature (Tc1) of at least 10 ° C below the melting point of the DD-salt, the condensation step (i The DD-salt obtained therein to produce a solid prepolymer; and (ii-b) further to a second temperature of at least 15 ° C below the melting temperature of the prepolymer and the melting temperature at which the polyamine is to be obtained. The solid prepolymer obtained in the step (ii-a) is condensed at a condensation temperature (Tc2), whereby the polyamine is obtained in a solid state.

The advantage of this first preferred aspect of the invention is that the process can be carried out at high reaction temperatures while achieving high reaction rates, and unpredictably producing semi-aromatic polyamines in high yields with relatively short reaction times A high degree of polymerization occurs inside and no gelation occurs. The utility of this aspect of the invention is a generally efficient process that allows for the high utilization of manufacturing capabilities. The above results are obtained even without the need to add a catalyst, and despite the fact that the carboxylic acids mainly contain an aromatic dicarboxylic acid.

Therefore, in the first sub-step, the condensation temperature is maintained below at least 10 ° C below the melting temperature (Tm-salt) of the DD salt, and in the second Or in another substep, the condensation temperature may be increased to be even higher than the melting temperature of the DD salt, and may be maintained at the melting temperature of the prepolymer, the melting temperature of the desired polyamine and The melting temperature of any intermediate condensation product is equal to or lower. The condensation temperature in this second or further substep is preferably at least 15 ° C, preferably at least 20 ° C, more preferably at least 25 ° C below the melting temperature of the polyamine and any intermediate condensation products thereof.

In addition to the use of separate sub-steps, the method can be carried out by applying a temperature gradient from a condensation temperature of at least 10 ° C below the Tm salt to a higher temperature and maintaining the polyamine and its Any intermediate condensation product has a melting temperature below at least 15 °C.

In the case of salt powders from the mixture of step (i) containing different DD salts, these salts may have different melting temperatures and different condensation rates at a particular temperature. The case is, for example, wherein the salt powder comprises a mixture of an aliphatic DD salt and an aromatic DD salt. Insofar as the DD salt having the lowest melting temperature can have the highest condensation rate, step (ii) can be carried out in two sub-steps, wherein in the first sub-step, at least below the minimum temperature of the salt melting temperature The salt having the lowest melting temperature is condensed into a polyamidamide prepolymer at a temperature of 10 ° C, and then the temperature can be raised and maintained at least 15 ° C below the melting temperature of the prepolymer and in other salts. At least 10 ° C below the melting temperature, at least 15 ° C below any other polyamine precursors and any intermediates thereof. Insofar as the DD salt having the lowest melting temperature can have the same or lower condensation rate, Tc1 in step (ii-a) can be maintained below the lowest temperature of the salt melting temperature.

It is worth noting that Tc1 and Tc2 are not necessarily different, and the like may be the same. If different, Tc2 is preferably higher than Tc1, and more preferably higher than Tm salt, so that a higher condensation rate can be obtained.

By prepolymer herein is meant a polyamine condensation product having a viscosity value of at least 8 ml/g. In order to raise Tc2 above the Tm salt, the prepolymer preferably has a viscosity value of at least 10 ml/g, more preferably at least 15 ml/g, and even more preferably at least 20 ml/g.

Tc1 is preferably at least 210 ° C, and more preferably, Tc1 is higher than 220 ° C, more preferably at least 230 ° C, still more preferably at least 240 ° C. In the case of Tc1, a higher reaction temperature can make the reaction faster and the reaction time shorter.

Tc2 is preferably at least 240 °C. Also in a preferred embodiment, Tc2 is at least 25 ° C below the melting temperature of the intermediate, condensation product and any intermediate condensation products thereof.

The viscosity values herein are determined in accordance with ISO 307 (4th edition) at 25 ° C in 96% sulfuric acid (0.005 g / ml).

In step (ii-b), the polyamido prepolymer is further condensed to obtain the polyamine having a desired molecular weight. The duration of this step (ii-b) may depend on the processing conditions and the degree of polymerization desired. The statement "degree of polymerization desired" is not limited to one method or number of times. The desired degree of polymerization can generally depend on the intended use of the polyamine. It can be determined by any suitable method. The degree of polymerization can be determined, for example, by polymer properties such as viscosity, mechanical properties, or molecular weight. The degree of polymerization can also be derived from the conversion of the carboxylic acid groups and the amine groups and is expressed, for example, by the ratio 1/(1-ρ). The conversion ρ herein is the mole of the reacted carboxylic acid groups and amine groups relative to the initial total moles of these functional groups present in the DD salt.

The condensation step (ii), and each of the substeps (ii-a) and (ii) may be carried out in any manner suitable for the conventional SSP process, such as in a fixed bed reactor, a moving bed reactor, or a stirred reactor. -b). In the case of a lower melting DD salt and a DD salt which is readily adhered upon release of water (such as in the case of an aliphatic DD salt), step (ii-a) preferably uses a stirred bed reactor such as a rotating vessel or machine. The stirred reactor in which the solid DD salt and the solid prepolymer are stirred, thereby maintaining activity and recycling. The use of a stirred bed reactor helps to obtain the result that the polymer obtained by this method is a non-sticky powder or particulate material. The polyamide powder finally has a uniform free flow. In the case of the second condensation step (ii-b), a fixed bed reactor (such as a batch operated upright column reactor) or a moving bed reactor (such as a continuously operated upright column reactor) may be an economical one. Better choice.

The salt preparation step (i) and the solid state polymerization (ii) in the process according to the invention are suitably carried out in an inert gas atmosphere. As the inert gas atmosphere, a suitable gas generally known for the polymerization of polyamine can be used. The inert gas is typically an oxygen-free or essentially oxygen-free inert gas, and no other oxidation-reactive gases such as O3, HNO3, HClO4, and the like. It is preferred to use nitrogen as the inert gas. The salt preparation and the polymerization steps are preferably carried out at atmospheric pressure or under slight overpressure (e.g., in the range between 1 and 5 bar, for example, at about 1.5, or 2 or 3 bar). The advantage of using an overpressure is that the loss of diamine during salt preparation can be reduced, even if there is a loss.

During the salt preparation step (i) and more advantageously, during the solid state polymerization step (ii), an inert gas purge is used to carry out the process. During the heating step prior to the solid state polymerization, an inert gas purge can be used to remove any water originally present in the DD salt. An inert gas flush also helps to effectively remove water from the condensation reaction, thereby reducing the risk of adhesion (agglomeration) of the reaction mixture and contributing to, for example, the pressure relief valve, the metering line, and the method Other (flush) lines inside and protect the mechanical seal. Preferably, the appropriate level of the gas scrubbing agent is selected based on economy and efficiency and can be determined by routine experimentation.

The heating and cooling can be carried out by heating the inert gas used for scrubbing, or by heating any combination of the reactor walls or the interior or the like. This heating is preferably carried out using a temperature rise method for the heating. It gradually increases the temperature of the contents of the reactor and gives a gradient for the temperature of the condensation reaction. The advantage is that after a long period of time, the water produced by the condensation reaction can be released and removed more easily, thus minimizing the chance of rusting.

The solid state polymerization step (ii) can be carried out, for example, as follows. The DD salt is prepared in a polymerization reactor, or the DD salt can be charged into a polymerization reactor. Preferably, the DD salt is first heated to a specified temperature (preferably about 130 ° C) in the range of from 100 to 160 ° C by a first temperature ramp to allow any water in the DD salt to be released by evaporation and via the polyester The gas is purged and carried away while maintaining the temperature of the reactor wall and interior therein at the same temperature or at a higher temperature to avoid condensation reactions on the surfaces. If it is necessary to remove water from the DD salt, it is preferred to prepare the solid DD salt at the specified temperature. It can be confirmed, for example, by a water collector. Once the water removal step is completed or almost completed, the solid DD salt is subjected to a second temperature rise The method is heated to a specified point equal to Tc1. The first condensation reaction step can be followed by the rate of formation of the condensate, which begins slowly and then increases. This prepolymerization will typically proceed until the condensate collection rate drops significantly. The completion of the conversion of the DD salt can also be confirmed by DSC in the absence of residual melting enthalpy for the melting peak of the DD salt. In the second condensation reaction step, the solid prepolymer formed can be maintained at the same temperature (ie, Tc2 is equal to Tc1), or further condensed at a lower temperature, or can be swelled by a third temperature. The method is heated to a specified point equal to Tc2 and higher than Tc1. The polyamine is maintained at this temperature until the desired degree of polymerization is obtained. Once the polymerization is complete, the polymer is cooled and discharged from the reactor.

It has been found that during the first condensation reaction step (ii-a), the loss of the diamine is considerably limited. In the case of a DD salt having a diamine/dicarboxylic acid molar ratio greater than one, the loss is generally not much greater than the amount corresponding to the excess of the diamine. For a DD salt having about one or less than one diamine/dicarboxylic acid molar ratio, the loss is typically on the order of only a few hundred, if not, rarely. It has not been found that a possible diamine deficiency will reduce the rate of the reaction. The advantages of this method according to the invention are not so demanding in terms of a small loss of diamine relative to the rate of polymerization. A medium to high molecular weight polymer can be readily obtained. The polyamine thus obtained has a viscosity value of at least 20 ml/g, preferably at least 35 ml/g, more preferably at least 50 ml/g, or even at least 65 ml/g.

The degree of polymerization can be increased by limiting the flow of the gas within the first condensation reaction step. In order to obtain a higher degree of polymerization, it is preferred to add a diamine during the solid state polymerization. It is best to spray liquid diamine to each of the opposite The diamine in gaseous form is introduced on the component or by the inert gas scrubbing agent to add the supplemental diamine. It can be carried out, for example, during step (ii-a) or step (ii-b), or any combination thereof.

In the case of branched diamines which typically form lower molten salts, even in the case of aromatic dicarboxylic acids (e.g., for citric acid), it is preferred to add the diamine during step (ii-b). The branched diamine is a diamine containing one or more alkyl groups along the main chain of the alkylene diamine monomer. Examples of branched aliphatic diamines are 2,2-dimethyl-1,3-propanediamine, 2-methyl-1,5-pentamethylenediamine, 2-methyl-1,9-anthracene. Diamine, trimethyl-1,6-hexamethylenediamine and isophorone diamine.

In a preferred embodiment of the process according to the invention, a supplemental diamine is added during the second condensation reaction step (ii-b).

In another preferred embodiment of the method, a monofunctional monomer is added during the second condensation reaction step. The monofunctional monomer is preferably a monofunctional amine such as dodecylamine; or a monofunctional carboxylic acid such as benzoic acid. The advantage of adding the chain terminator allows the high molecular weight polyamine to be obtained in a reasonably short time, and at the same time, the polyamine can be well melted in terms of viscosity retention during the melt processing. Stability. The amount of the monofunctional monomer is preferably at most 2.0 mol%, preferably at most 1.0 mol%, relative to the total amount of the dicarboxylic acid.

Trifunctional or higher functional monomers may also be added, which are preferably added during the second condensation reaction step. These monomers can act as branching agents. To prevent excessive branching and gelation, the amount of such monomers is preferably at most 1.0 mole%, preferably at most 0.5 mole%, relative to the total moles of the dicarboxylic acid.

If appropriate, add supplemental diamines and / or chain stoppers and / or three / A combination of higher functional monomers.

In the process according to the present invention, the solid DD salt may contain a small amount of a catalyst which does not lower the melting point of the salt too much and which still obtains the effects of the present invention. However, the amount should be limited so that the Tm salt is not lower than 265 °C. Preferably, the solid DD salt is prepared in the absence of a phosphorus-containing polycondensation reaction salt.

In the method of the present invention, a solid-state polymerization reaction is carried out by diamine/dicarboxylate (DD salt) prepared from a diamine and a dicarboxylic acid containing an aromatic dicarboxylic acid to prepare an AA- BB polyamine.

The DD salt provided in step (ii) of the process according to the invention is obtained by partitioning the diamine to a stirred powder comprising an aromatic dicarboxylic acid. Preferably, the diamine consists of a diamine or a mixture of at least two diamines. The dicarboxylic acid may also consist of a dicarboxylic acid or a mixture of at least two dicarboxylic acids. Preferably, the DD salt is a salt of at least one aromatic dicarboxylic acid and a mixture of at least two diamines.

The DD salt can also be a physical mixture containing two different salts. This physical mixture can be prepared by using a stirred powder comprising a physical mixture of at least two dicarboxylic acids. Alternatively, the salts may be prepared separately according to step (i) (thus as in step (i), each comprising partitioning the diamine to a stirred powder containing an aromatic dicarboxylic acid) and performing step (ii) The physical mixture is prepared by premixing the salts.

The aromatic dicarboxylic acid preferably comprises a combination of p-nonanoic acid, 2,6-naphthalene dicarboxylic acid and biphenyl-4,4'-dicarboxylic acid, or the like. The aromatic dicarboxylic acid is preferably selected from the group consisting of p-citric acid, 2,6-naphthalenedicarboxylic acid and biphenyl-4,4'-dicarboxylic acid. These are better The aromatic dicarboxylic acid contributes to the formation of the DD salt as a solid powder and forms a DD salt having a higher melting temperature which allows higher processing temperatures. More preferably, the dicarboxylic acid comprises p-citric acid or even p-citric acid.

The dicarboxylic acid from which the DD salt is prepared may further comprise an aliphatic dicarboxylic acid. The aliphatic dicarboxylic acid is preferably an acyclic dicarboxylic acid (straight or branched chain), a cyclic dicarboxylic acid, or a combination thereof. The aliphatic dicarboxylic acid is preferably an aliphatic dicarboxylic acid having 4 to 8 carbon atoms. The aliphatic dicarboxylic acid is also preferably selected from the group consisting of 1,4-succinic acid (also known as succinic acid), 1,6-hexanedioic acid (also known as adipic acid), 1,8 - Suberic acid (also known as succinic acid) and 1,4-cyclohexanedicarboxylic acid.

The aliphatic dicarboxylic acid preferably comprises, or preferably consists of, adipic acid, or trans-1,4-cyclohexanedicarboxylic acid, or a combination thereof. Adipic acid is the most widely used aliphatic dicarboxylic acid for semi-crystalline polyamines, and trans-1,4-cyclohexanedioic acid can be used to prepare semi-crystalline polyamines having a higher melting point.

The aliphatic dicarboxylic acid and the aromatic dicarboxylic acid are preferably present in a physical mixture of the powders of the respective dicarboxylic acids. In this case, as is generally observed in the DSC assay by observation of the different melting temperatures of the respective salts, the salt preparation step provides a physical mixture of salts.

In a preferred embodiment of the present invention, the dicarboxylic acid is composed of (a) one selected from the group consisting of p-phthalic acid-2,6-naphthalenedicarboxylic acid and biphenyl-4,4'-dicarboxylate. An aromatic dicarboxylic acid of an acid, or a combination thereof; (b) alternatively, an aliphatic dicarboxylic acid selected from the group consisting of adipic acid and cyclohexanedicarboxylic acid, or a combination thereof; and (c) relative The total molar amount of the dicarboxylic acid is up to 10 mol% of the other dicarboxylic acid.

The aromatic dicarboxylic acid preferably accounts for at least 50 mole % relative to the total moles of dicarboxylic acid in the stirred powder in step (i) of the present invention. Thus, the dicarboxylic acid in the DD salt may comprise at least 50 mole % of the aromatic dicarboxylic acid in the DD salt formed therefrom relative to the total molar amount of the dicarboxylic acid in the DD salt. . This advantage allows for easier preparation of a readily flowable powder in the salt preparation step (i). Another advantage is that the time required for the first condensation step (i) before the temperature can be raised can be further reduced without causing adhesion problems, thus allowing the aromatic DD salt to undergo a polycondensation reaction faster, and In the case where the amount of the aromatic dicarboxylic acid is less than 50 mol%, the total polymerization reaction time can be shortened.

The dicarboxylic acid in the stirred powder in step (i) and the dicarboxylic acid in the DD salt in step (ii), respectively, comprises at least 75 mole percent, relative to the total moles of the dicarboxylic acid Group dicarboxylic acid. Due to the higher content of aromatic dicarboxylic acid, a higher condensation reaction temperature and a faster rate of conversion to polyamine are allowed without fouling and/or formation of agglomerates.

Preferably, the dicarboxylic acid consists essentially of an aromatic dicarboxylic acid (i.e., at least 99 mole %) or an aromatic dicarboxylic acid selected from the group consisting of citric acid, A combination of 2,6-naphthalenedicarboxylic acid and biphenyl-4,4'-dicarboxylic acid, or the like. It even allows for higher heating rates and condensation reaction temperatures and even shorter reaction times.

The diamine used in the process according to the invention is preferably selected from the group consisting of aliphatic diamines and aliphatic-aromatic diamines or combinations thereof. The aliphatic-aromatic diamine is a diamine in which each of the amine groups is directly bonded to an aliphatic molecular group, and the aliphatic molecular groups are then linked to an aromatic molecular group.

The aliphatic diamine may comprise a linear aliphatic diamine, a branched aliphatic diamine or a monoaliphatic diamine, or a combination thereof.

The aliphatic diamine preferably comprises a C2-C10 diamine, i.e., a diamine having from 2 to 10 carbon atoms. The C2-C10 aliphatic diamine is preferably selected from the group consisting of 1,2-ethylenediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexane. An amine, and 1,4-cyclohexanediamine, which are examples of a C2-C6 diamine; and 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonanediamine, and 1,10-decanediamine, which is an example of a C7-C10 diamine.

The aliphatic diamine preferably comprises a C4-C6 diamine such as 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, trans-1,4-cyclohexane amine.

More preferably, the diamine comprises a straight chain C4-C10 diamine, more specifically, 1,4-butanediamine, 1,5-pentanediamine, and 1,6-hexanediamine, or trans-1,4 a combination of cyclohexanediamine or the like. It provides a DD salt with a higher melting point which allows for higher condensation reaction temperatures and limits the risk of particle sticking.

The diamine also more preferably comprises at least 50 mole % C2-C6 diamine, and even more preferably at least 75 mole %, relative to the total moles of diamine in the DD salt. It also gives salts with higher melting temperatures and copolyamines, thus allowing higher processing temperatures during the condensation reaction steps (ii-a) and (ii-b) without increasing the risk of adhesion.

The DD salt prepared from the aromatic dicarboxylic acid suitably has a melting temperature of at least 240 ° C (where ° C is Celsius), more preferably at least 250 ° C, for example in the range of 260-330 ° C.

Examples of such salts include XY salts wherein X is a C2-C10 diamine, or combinations thereof, and Y is selected from the group consisting of p-nonanoic acid, 2,6-naphthalenedicarboxylic acid, and Biphenyl-4,4'-dicarboxylic acid, or a combination thereof.

Accordingly, the semicrystalline semi-aromatic polyamine obtained from the aromatic DD salts preferably has a melting temperature of at least 260 ° C, preferably at least 280 ° C. The semicrystalline polyamine preferably has a melting temperature in the range of from 260 to 370 ° C, or even more preferably in the range of from 280 to 350 ° C. It allows the polyamine to be processed in a molten state. Moreover, the polyamine which is derived from the combination of the aromatic DD salt and a fatty acid DD salt can also be processed in a molten state to form a homogeneous copolyamide. In fact, surprisingly, in spite of the fact that in the case of the polymerization, a physical mixture of salts is used and the polymerization is carried out in the solid state, the process can obtain an aliphatic polyfluorene of the aliphatic DD salt. a block copolymer of an amine, a semi-aromatic polyamine with the aromatic DD salt, such as from the melting temperature of the polymer, is found to be easily via a guanamine conversion reaction occurring in the melt The ground is converted into a random copolyamide. The semi-crystalline semi-aromatic polyamine obtained from the aromatic DD salts may also have a melting temperature of 370 ° C or higher. The case may be that in the homopolymer of the XY salt, X is, for example, 1,2-ethanediamine, 1,4-butanediamine, 1,6-hexanediamine or trans-1,4-cyclod. Hexamethylenediamine, and Y is p-citric acid, 2,6-naphthalenedicarboxylic acid or biphenyl-4,4'-dicarboxylic acid.

In a particular embodiment of the invention, the DD salt from step (i) comprises an aromatic dicarboxylic acid (Y) and an aliphatic diamine (X), and the polyamine obtained by the method It is a semi-aromatic polyamine homopolymer (which is represented by PA-XY). Examples of suitable salts for such homopolymers include XT salts wherein T is p-nonanoic acid and X is selected from the group consisting of 1,2-ethylenediamine, 1,3-propanediamine, 1,4-butane A linear C2-C8 diamine of an amine, 1,5-pentanediamine, and 1,6-hexanediamine. Combined Examples of suitable polyamine homopolymers include PA-2T, PA-3T, PA-4T, PA-5T, PA-6T, PA-7T, and PA-8T. Even if such homopolymers can have very high melting temperatures, or even degrade before melting, by using the process of the invention, these salts can be carried out at a temperature that is still well below the melting/degradation temperature of the polymer. The polymerization is carried out, and a high conversion rate is obtained and a high molecular weight is obtained, and a side reaction which causes gelation does not occur.

According to a second preferred aspect of the present invention, the dicarboxylic acid comprises an aromatic dicarboxylic acid selected from the group consisting of p-citric acid, 2,6-naphthalenedicarboxylic acid and biphenyl-4,4'-dicarboxylic acid, and The liquid diamine comprises a mixture of at least two aliphatic diamines selected from the group consisting of C2-C10 diamines.

The inclusion of a second aliphatic diamine in the DD salt of the present invention has been found to undesirably accelerate the rate of solid state polymerization within step (ii) of the process of the present invention.

More preferably, the DD salt comprises predominantly an aromatic dicarboxylic acid (Y) and at least two diamines (X ₁ and X ₂ ) and, optionally, one or more additional diamines (collectively referred to as X _n ). These salts can be represented by X ₁ Y/X ₂ Y salts and X ₁ Y/X ₂ Y/X _n Y salts, respectively. The corresponding copolyamines are likewise represented by PA-X ₁ Y/X ₂ Y and PA-X ₁ Y/X ₂ Y/X _n Y, respectively.

The corresponding salts can be prepared by the salt preparation step (i) by first producing a liquid mixture containing at least two diamines and then dispensing the liquid mixture to the stirred powder containing the dicarboxylic acid powder.

The semi-aromatic copolyamine preferably comprises at least one aliphatic C2-C6 diamine, that is, X1 is a C2-C6 diamine. X2 and/or Xn may optionally comprise a diamine of a non-aliphatic diamine. X1 is better with at least another aliphatic The C2-C10 diamines are combined, that is, X2 is an aliphatic C2-C10 diamine.

The ratio of these diamines can vary widely. For example, the molar ratio X ₁ /(X ₂ +X _n ) is in the range of 99/1-1/99. If it is higher than the ratio of 99/1, the (co)polyamine is preferably regarded as a homopolyamine, and it is often possible to have a trace amount of other diamine. The molar ratio X ₁ /(X ₂ +X _n ) is preferably in the range of 95/5-5/95, or more preferably 90/10-10/90 and 75/25-25/75. Preferably, the C2-C6 diamine has a molar amount of at least 50 mole percent relative to the total moles of the diamines.

The DD salt and the corresponding semi-crystalline semi-aromatic (co)polydecylamine have such a monomer combination which allows the melting temperature to be in the range of from 280 to 350 ° C (more preferably from 300 to 340 ° C). These (co)polyamines have good processing properties as well as good high temperature properties.

Examples of suitable copolyamines which can be made using the process of the invention include the following copolymers: PA-2T, PA-3T, PA-4T, PA-5T, PA-6T, such as PA-4T/XT, PA- 6T/XT, such as PA-4T/6T, PA-6T/5T, PA-4T/10T, PA-6T/10T, PA-6T/4T/10T, PA-6T/9T, PA-6T/7T, PA -4T/8T, PA-4T/6T/10T and PA-4T/10T, PA-6T/8T, PA4T/DACHT (where DACH refers to trans-1,4-diaminocyclohexane), and corresponding Copolyamines, wherein the tannic acid (T) is substituted with 2,6-naphthalene dicarboxylic acid or biphenyl-4-4' dicarboxylic acid. Herein, 4 represents a repeating unit derived from 1,4-butanediamine, 5 represents a repeating unit derived from 1,5-pentanediamine, 6 represents a repeating unit derived from 1,6-hexanediamine, and 7 represents a derivative. From the repeating unit of 1,7-heptanediamine, 8 represents a repeating unit derived from 1,8-octanediamine, and 10 represents a repeating unit derived from 1,10-nonanediamine. D represents a repeating unit derived from 2-methylpentamethylenediamine, and 2-Me8 represents a repeating unit derived from 2-methyl-1,8-octanediamine.

If it is rare, the content of the optical chain aliphatic diamine in the salt process is preferably limited to 10 mol% of the diamine.

Preferably, it is a DD salt mainly comprising the following components: an aromatic dicarboxylic acid selected from the group consisting of citric acid, 2,6-naphthalenedicarboxylic acid or biphenyl-4-4' dicarboxylic acid, and at least two selected from the group consisting of Aliphatic diamines of C4, C6 and C10 diamines.

In general, salts of aromatic dicarboxylic acids have melting temperatures higher than their aliphatic dicarboxylate analogs.

a DD salt prepared from the aliphatic dicarboxylic acid (referred to herein as an aliphatic DD salt which may be derived from the DD salt of the aromatic dicarboxylic acid in step (i) of the process according to the invention The (referred to as an aromatic DD salt) preferably has a melting temperature of at least 170 ° C, preferably at least 180 ° C or at least 190 ° C. Examples of such salts include XY salts wherein X is 1,4-butanediamine, 1,5-pentanediamine, or 1,6-hexanediamine, and Y is adipic acid or trans-1, 4-cyclohexanedicarboxylic acid.

If the copolyamine is prepared from a mixture comprising an aromatic DD salt and an aliphatic DD salt, the diamine and the aliphatic dicarboxylic acid are preferably selected to result in a fat derived only from the aliphatic DD salt. The polyamidoamine becomes a semi-crystalline polyamine. The aliphatic semi-crystalline polyamine may preferably have a melting temperature of at least 230 ° C, preferably at least 240 ° C, more preferably at least 250 ° C, and most preferably in the range of 260-300 ° C. The advantage of using a combination of this aliphatic DD salt with the aromatic DD salt (at least at least 50 mole % of the aromatic DD salts) converts the aliphatic DD salt in the first condensation step (ii-a) After forming a prepolymer, after a short period of time, the temperature Tc2 of the second condensation step (ii-b) can be increased, and the particles do not adhere, and a high reaction rate is obtained. The total time required for the polymerization of the short conversion time and the polyamine to obtain the desired degree of polymerization can be shortened.

Examples of suitable copolyamines include copolymers of PA-XT with PA-X6 or PA-XCHDA (wherein X comprises a C4-C6 diamine), or combinations thereof. For example, PA-4T/46, PA-4T/4CHDA, PA-6T/66, PA-6T/6CHDA, and PA4T/DACH6. CHDA herein represents trans-1,4-cyclohexanedicarboxylic acid derivatized by a repeating unit.

The invention also relates to polyamines made by the process according to the invention, and any particular or preferred embodiments thereof. The invention relates in particular to a polyamine obtained by the process according to the invention, wherein the polyamine is a semi-crystalline semi-aromatic homopolyamine or a semi-crystalline semi-aromatic copolyamine.

Preferably, the polyamine has a viscosity value of at least 20 ml/g, preferably at least 35 ml/g, more preferably at least 50 ml/g, or even at least 65 ml/g.

Polyamines obtained by the process of the present invention have been found to have a unique appearance characterized by a particular morphology. The DD salt produced in step (i) is generally composed of polycrystalline particles containing polycrystallites. During the solid state polymerization of the salts, the powder is directly reacted with the powder, or the powder is first granulated or sized in a solid state, and the general physical properties of the DD salt powder, such as the basic morphology, are mainly borrowed. The polyamide powder thus obtained is maintained. An example of a polyamide pigment particle obtained using the method according to the present invention is shown in Figure 1.

Figure 1 shows a semi-crystalline form made by the method according to the invention SEM image of powder particles of semi-aromatic polyamine. The powder particles have a size of several hundred microns. The powder particles represent a microporous structure in which pores, cracks, and many small crystallites are visible at the surface. A portion of the second particle can be seen on the left side of the figure.

In the case of the polyamide powder, the microcrystalline microporous structure is represented by a relatively high BET surface value and contains relatively large particles. Preferably, the polyamide powder has a BET value of at least 0.4 m2/g as determined by the method of ISO 9277:2010, and is determined by the method according to ISO 13320, and has a d of at least 50 micrometers (μm). 50 particle size distribution. The BET value may even be in the range of 0.6-1.5 m2/g and the d50 is at least 100 microns.

The invention is further illustrated by the following non-limiting examples and comparative experiments.

experiment raw material

For tannic acid: powder, technical grade (particle size distribution: d10 = 35.8 microns; d50 = 127 microns; d90 = 264 microns; span 2.36); melting temperature above 400 °C.

Adipic acid: powder, technical grade (particle size distribution: d10 = 102 microns; d50 = 349 microns; d90 = 758 microns; span 1.49); melting temperature 152 °C.

1,4-butanediamine: (1,4-diaminebutane, DAB) technical grade; up to 1% by weight of water, impurities in the ppm range; melting temperature 27.5 °C.

1,6-hexanediamine: (hexamethylenediamine, HMDA) technical grade; maximum 1% by weight water, impurities in the ppm range; melting temperature 41 °C.

1,10 癸 diamine; up to 1% by weight of water, impurities in the ppm range; melting temperature 62 ° C.

Sodium hypophosphite monohydrate, available from Sigma Aldrich, up to 1% by weight water, impurities in the ppm range.

experiment method End group in DD salt

The NH2 and CO2H contents in the DD salts were determined by potentiometric titration using a Metrohm type Titrando 808 processor having a Metrohm combi electrode using a 3M KCl fill solution as obtained. 0.1 g of the salt sample was weighed out and placed in a 100 ml glass cylindrical titration vessel equipped with a PTFE (Teflon) coated magnetic stir bar and dissolved in 12.5 ml of water, followed by the addition of 37.5 ml of ethanol. The solution was titrated with a solution of 0.1 N HCl in water to obtain a NH2 content. For the CO2H end-group titration, a solution of a sample solution as described above and titrated with 0.1 N NaOH in water was used. The two titrations were subjected to a blank test using 50 ml of a 75 vol%/25 vol% ethanol/water solvent. The NH2 and CO2H end group content was calculated according to the following equation.

Where: VHCl 1 = HCl titration solution for sample titration

VHCl 0=ml of HCl titration solution for blank titration

VNaOH 1 = milliliters of NaOH titrant for sample titration

VNaOH 0 = number of milliliters of NaOH titrant for blank titration

tHCl = molar concentration of the HCl titrant (mole / liter)

tNaOH = molar concentration of the NaOH titrant (mole / liter)

a = number of samples (g)

Viscosity value (VN)

The viscosity value (VN) was measured according to ISO 307 (4th edition). The measurement was carried out using a pre-dried polymer sample and the drying step was carried out at 80 ° C under high vacuum (i.e., less than 50 mbar) over 24 hours. The viscosity value was determined at a concentration of 96.00 ± 0.15% m/m of 100 ml of sulfuric acid at 0.55 ± 0.05 °C. The flow time (t) of the solution and the flow time (to) of the solvent were determined using a DIN-Ubbelohde from Schott (Ref. No. 53020) at 25 °C. The definition of VN is

Where: VN = viscosity value expressed in milliliters per gram

t = average flow time of the sample solution expressed in seconds

t ₀ = average flow time of the solvent in seconds

c = concentration expressed in grams per milliliter (=0.005)

The salt and the melting temperature (Tm) of the polymer and the melting enthalpy (ΔHm) determined by the DSC method

Using the differential scanning calorimetry (DSC), the thermal properties and characteristics of such salts (such as melting temperature and melting enthalpy), residual melting enthalpy of intermediates, using the method according to ISO 11357-3 (2009), And the melting temperature of the polymers. The residual enthalpy of enthalpy is used as a control within the conversion for the reaction of the salts and converted to a polyamine (pre)polymer.

For these assays, a standard heat flux Mettler DSC 823 was used and the following conditions were used. A sample of about 3 to 10 milligrams in mass was weighed out on a precision balance and encapsulated (curled) in 40 microliters of aluminum crucible of known quality. The aluminum crucible was sealed with a porous aluminum crucible lid. The porous body was mechanically made and consisted of a pore width of 50 microns. An identical open space was used as a control. Nitrogen flushing was carried out at a rate of 50 ml min ^-1 . A heating-cooling-heating cycle having a scan rate of 20 ° C/min in the range of 0 to 380 ° C is used to determine the thermal properties that can numerically represent the materials of study (the two salts in polymer form) parameter. The melting peaks in the first heating cycle are used for the melting temperatures of the salts and polymers and the residual melting enthalpy.

Determination of the BET value

The BET values of the salt powders and the polyamide powders were determined by the specific surface area-BET method for measuring solids by gas adsorption according to ISO 9277:2010. The samples were analyzed on a Micromeritics TriStar 3000 gas adsorption analyzer. The samples were degassed in vacuum at 100 ° C prior to the adsorption measurements.

Salt method Example I: Preparation of 6T/4T salt (61/39 mol/mole) in a stirred powder bed

61.21 grams of solid p-citric acid (0.369 moles) powder was charged to a 1.0 liter baffle flask. The flask was connected to a rotary evaporator equipped with a heated diamine batching vessel, and washed with 5 grams of nitrogen per hour, inerting for 1 hour. The contents of the flask were mixed by rotating the flask at 50 rpm and kept under a nitrogen atmosphere (5 g per hour). The rotating flask was partially immersed in an oil bath maintained at 65 ° C to bring the powder to the same temperature. 12.67 g of 1,4-butanediamine (0.144 mol) and 26.12 g of 1, were prepared by melting and mixing the diamine in the batching container at 60 ° C (which corresponds to a compounding temperature of 60 ° C). A liquid mixture of 6-hexanediamine (0.225 mol). The liquid mixture was added dropwise to the acid powder in 4 hours at a batching rate of 0.42 mol%/min under constant rotation. After completion of the batching, the reaction mixture was stirred by rotation and the flask was maintained in the oil bath at a temperature of 65 ° C for a further 120 minutes. The flask was then cooled to room temperature and the salt was drained from the flask. The salt thus obtained is a powder. The results of the analytical properties of the salt are shown in Table 1.

Example II: Preparation of 6T salt in a stirred powder bed

In addition to using a 2.0 liter baffle flask, 294.18 grams (1.77 moles) of citric acid powder was added and a mixture of 215.82 grams (1.86 moles) of 1,6-hexanediamine (HMDA) and 29.74 grams of water was added dropwise. The salt was prepared as described in Example I. The HMDA/water mixture was maintained at a temperature of 80 ° C, which is the temperature of the furnish. The batching rate was 1.0 g/min (0.3875 mol% total diamine per minute). After the batching was completed, the temperature of the stirred powder was maintained at 65 ° C for 120 minutes while stirring. The flask was then cooled to The salt was discharged from the flask at room temperature. The salt of the powder is obtained. The results of the analytical properties of the salt are shown in Table 1.

Example III: Preparation of 4T salt in a stirred powder bed

Aside from a 2.0 liter baffle flask filled with 326.65 grams (1.97 moles) of citric acid powder and a drop of 183.35 grams (2.08 moles) of 1,4-butanediamine (DAB), as described in Example I This step prepares the salt. The temperature of the DAB was maintained at 80 ° C and the temperature of the oil bath in which the baffled flask was heated was maintained at 65 °C. The batching rate was 1.0 ml/min (0.55 mol% of total diamine per minute). After the formulation was completed, the temperature of the stirred powder was maintained at 65 ° C for 120 minutes while stirring. The flask was then cooled to room temperature and the salt was drained from the flask. The salt is obtained in powder form. The results of the analytical properties of the salt are shown in Table 1.

Example IV: Preparation of 6T/4T salt (64/36 mole/mole) in a stirred powder bed

The 228.91 was first charged with citric acid in a 1 liter electric heating cylindrical vessel equipped with a heated upper stirring device. The reactor was equipped with a dosing system connected to a heated diamine batching container which was conditioned by a nitrogen purge of 5 grams per hour. The contents of the reactor were mixed at 60 rpm and inerted by nitrogen flushing. The reactor contents were heated to a temperature of 60 ° C by the jacket temperature and the upper temperature was maintained equal to the jacket temperature. The diamine was melted and mixed in the batching vessel at 60 ° C to prepare 103.26 g of 1,6-hexanediamine and 44.83 g of 1,4-butanediamine (64/36 mol%/mole). %) liquid mixture. The liquid mixture was added dropwise via the batching system over 5 hours at constant rotation (60 rpm) while maintaining the powder temperature of the mixture at 60 ° C and during and after the addition of the diamines, Maintain a nitrogen flow of 5 grams per hour. After the partitioning of the diamines is completed, the reaction mixture is heated from 60 ° C to 150 ° C in one hour and maintained at this temperature, which takes two hours and allows the volatile components to leave the reactor. The reactor contents were then cooled to below 50 °C within two hours. The salt thus obtained is a powder. The analysis results of the salt are shown in Table 1. These results are similar to those of Example I. It was demonstrated that the salt was completely formed in both cases, and in the case of Example IV, the segmentation treatment at 150 °C did not result in significant loss or premature reaction of the diamine.

Example V: Preparation of 4T/6T/10T salt in a stirred powder bed (10/60/30 mole/mole/mole, and 2 mole % DAB excess relative to salt)

In addition to using a 2.0 liter baffle flask, 280.26 g (1.687 mol) of citric acid powder was charged and added dropwise with 117.65 g (1.012 mol) 1 by melting at 60 ° C and mixing the diamines. The procedure described in Example I was followed by a liquid mixture of 6-hexanediamine, 24.87 grams (0.282 moles) of 1,4-butanediamine, and 87.22 grams (0.506 moles) of 1,10-decanediamine. Into the salt. The temperature of the diamine mixture was maintained at 60 ° C and the temperature of the oil bath in which the baffled flask was heated was maintained at 65 °C. The batching rate was 1.0 g/min. After the batching was completed, the temperature of the oil bath was maintained at 65 ° C, and it took 120 minutes while stirring. The flask was then cooled to room temperature and the salt was drained from the flask. The salt is obtained as a powder. The results of the analytical properties of the salt are shown in Table 1.

Example VI: Preparation of 46/66/4T/6T salt in a stirred powder bed

In addition to using a 2.0 liter baffle flask, charge 238.21 grams (1.434 moles) of citric acid powder and 38.46 grams (0.263 moles) of hexamethylenediamine, then add one drop A liquid containing 144.87 g (1.247 mol) of 1,6-hexanediamine and 45.27 g (0.514 mol) of 1,4-butanediamine prepared by melting and mixing the diamine at 60 ° C. The salt was prepared as described in Example I, except for the mixture. The temperature of the diamine mixture was maintained at 60 ° C and the temperature of the oil bath in which the baffled flask was heated was maintained at 65 °C. The batching rate was 1.0 g/min. After the batching was completed, the temperature of the oil bath was maintained at 65 ° C, and it took 120 minutes while stirring. The flask was then cooled to room temperature and the salt was drained from the flask. The salt is obtained as a powder. The results of the analytical properties of the salt are shown in Table 1. These DSC assays show two melting peaks.

Example VII: Preparation of 66/6T salt in a stirred powder bed

In addition to a physical mixture containing 75 grams of citric acid and 40.4 grams of adipic acid (62/38 moles per mole %) was charged into the 1.0 liter baffle flask and the liquid hexamethylenediamine was added dropwise. (86.6 g) was prepared in the same manner as described in Example I. The salt is obtained in powder form. The results of the analytical properties of the salt are shown in Table 1. These DSC assays show two melting peaks.

Example VIII: Preparation of diamine-deficient 4T/6T salt in a stirred powder bed

In addition to using a 2.0 liter baffle flask, 263.7 g (1.59 mol) of citric acid powder was charged, and then one drop was added, and 95.1 g (0.82 m) was prepared by melting and mixing the diamine at 60 ° C. The salt was prepared as described in Example I, except that the liquid mixture of 1,6-hexanediamine and 41.3 g (0.47 mol) of 1,4-butanediamine was used. The temperature of the diamine mixture was maintained at 60 ° C and the temperature of the oil bath in which the baffled flask was heated was maintained at 65 °C. The batching rate was 1.0 g/min. After the ingredients were completed, the temperature of the oil bath was maintained at 65 ° C for 120 minutes while stirring. Then, the flask is cooled to The salt was discharged from the flask at room temperature. The salt is obtained in powder form. The results of the analytical properties of the salt are shown in Table 1.

Example IX: Method for preparing granulated 46/66/4T/6T salt

2380 grams of citric acid powder and 385 grams of adipic acid were charged into a 15 liter plowshare mixer equipped with a gas inlet and gas outlet through the condenser. A mixture of 453 grams of 1,4-butanediamine and 1449 grams of hexamethylenediamine was prepared in a kit maintained at a temperature of 50 °C. 2.25 g of sodium hypophosphite monohydrate was dissolved in 13 g of water and added to the diamine mixture. At the beginning of the experiment, the solid acid was charged into the mixer and inerted by nitrogen flushing. Then, the diamine mixture was dispensed into the mixer at a rate of 30 ml/min and the stirrer was stirred at 60 RPM. After the amine mixture was dispensed, the mixer was heated to 100 ° C and 90 ml of additional water was added over 3 minutes. The temperature of the jacket was set at 110 ° C and the system was allowed to reflux for 40 minutes. The temperature of the jacket was then set at 150 ° C and all water and excess amine were evaporated. After opening, the mixer contains a mixture of salt particles.

Comparative Experiment A: Preparation of 6T/4T salt as catalyst in water (61/39 mol/mole)

61.21 grams of citric acid (0.369 moles) and 112 grams of demineralized water were added to a stirred vessel of 250 cubic centimeters. In the second step, 12.67 grams of 1,4-butanediamine (0.144 moles) and 26.12 grams of 1,6-hexanediamine (0.225 moles) were added. The temperature was increased to 95 ° C and mixed to obtain a clear aqueous salt solution. The pH of the salt solution formed was 7.4. Then 1.368 g of sodium hypophosphite monohydrate (catalyst) was added to the salt solution. The clear solution was concentrated in a rotary evaporator under a vacuum of 50 mbar and the solid white salt formed was removed from the vessel and dried in a vacuum oven at 60 ° C and 20 mbar to less than 0.1 weight. The amount of water in %. The salt formed was homogenized by crushing in a mortar and analyzed. The results of this analytical property are shown in Table 1.

Comparative Experiment B: Preparation of 6T/4T salt (61/39 mol/mole) using a catalyst in water

Comparative experiment A was repeated 4 times and the amount of salt obtained was combined.

Direct solid state polymerization Example I-a: Synthesis of a polymer by direct solid state polymerization of a 6T/4T salt of Example I (61/39 moles/mole) in a fixed bed reactor

Twenty grams of the salt powder of Example I was placed in a cylindrical glass tube having an inner wall of 10 mm and both sides were sealed with glass wool to retain the powder in the tube. The tube was placed in a glass bead packed bed. A nitrogen flow of 5 kg/hr was passed through the glass bead packed bed. Make the powder in the tube pass 1 g / h The nitrogen stream is inertized and takes 3 hours. The nitrogen flow is maintained at the local level during subsequent heating and cooling steps. The powder and the enclosed glass bead packed bed were heated to 120 ° C in 1 hour by preheating the nitrogen stream and then heated to a temperature of 260 ° C in 3 hours. This temperature was maintained at 260 ° C for 3 hours and then cooled to a temperature below 50 ° C in 1 hour. The polymer was obtained as a yellowish solid polymer powder (yield 17.28 g, 99.6% theoretical yield). The properties of the obtained polymer are represented by DSC. The first heating scan shows an endothermic melting spike characteristic equal to a polymer and its temperature is higher than the original salt spike. A small amount of residual unreacted salt was not detected. This DSC curve clearly shows the lack of salt spikes recorded as the starting material. The results of these analyses are shown in Table 2.

Comparative Experiment A-a: 6T/4T salt (61/39 mol/mole) synthetic polymer from Comparative Experiment A in a fixed bed reactor

Example I-a was repeated except that the 6T/4T salt powder of Comparative Experiment A was used. The product obtained in the glass tube (yield 17.1 g; 98.6% theoretical yield) consisted of a large brown solid block. The results of these analyses are shown in Table 2.

Example II-b: Synthesis of a polymer from the 6T salt of Example II in a stirred reactor

The polymerization is carried out in a two-layer, one-liter electric heating metal reactor equipped with a spiral stirring device, an inert gas inlet, and an outlet for leaving the inert gas and condensed gas out of the reactor, and measuring A thermometer for the temperature of the reactor wall and the contents of the reactor. A salt powder was charged into the reactor. The salt powder was stirred and 5 grams of nitrogen scrubbing per hour was applied to inertize the reactor contents. Then, by applying a program control The temperature profile heats the reactor wall to heat the reactor contents and monitor the temperature of the reactor contents within the powder bed while continuing the nitrogen purge and agitating the reactor contents.

300 grams of the salt of Example II was used. The nitrogen purge was arranged and maintained at a gas volume of 5 grams per hour at room temperature. The reactor contents were inerted within 3 hours before starting the heating profile. The reactor contents were heated from 25 ° C to 245 ° C over 180 minutes. The temperature was then further increased to 260 ° C over 90 minutes. This temperature was maintained at 260 ° C and took 90 minutes. The reactor contents were then cooled from 260 ° C to below 50 ° C in 110 minutes. The product obtained (260 g, 97.0% theoretical yield) consisted of a predominantly powder-containing micro-colored material with a small amount of small cakes. The results of the analysis are shown in Table 2.

Example III-b: Synthesis of a polymer from the 4T salt of Example III in a stirred reactor

Example II-b was repeated except that 300 grams of the 4T salt of Example III was used and 262 ° C was used instead of 260 ° C. The product formed (255 g, 96.9% theoretical yield) consisted of a micro-colored powdery material. The results of these analyses are shown in Table 2.

Example IV-b: Synthesis of a 6T/4T salt synthetic polymer from Example IV in a stirred reactor

The procedure of Example III-b was repeated except that 300 grams of the 6T/4T salt of Example IV was used and when 262 ° C was reached, 8 grams of 1,6-hexanediamine and 4 grams of 1,4- were added over 10 minutes. A liquid mixture of butane diamine. This temperature was then maintained below 262 ° C and took another 90 minutes. The reactor contents were then cooled from 262 ° C to below 50 ° C in 110 minutes. Yield 258 g (98.5% theoretical maximum yield). The polyamine powder formed had a BET value of 0.76 m ² /g and a particle size distribution of d10 of 19.7 micrometers, d50 of 140 micrometers, d90 of 602 micrometers, and a span of 2.64.

Example V-b: Synthesis of a 6T/4T/10T salt synthetic polymer from Example V in a stirred reactor

The procedure of Example II-b was repeated except that the 6T/4T/10T salt of 300 grams of Example V was used. The polymer is obtained in powder form. The yield was 262.5 g (97.4% theoretical maximum yield).

Example VI-b: Synthesis of Polyamine 46/66/4T/6T from the Salt of Example VI in a Stirred Reactor

The procedure of Example II-b was repeated except that the 46/66/4T/6T salt of 300 grams of Example VI was used. The reactor contents were heated from 25 ° C to 215 ° C in 3 hours, maintained at 215 ° C, took 3 hours, heated to 235 ° C in 5 hours, heated to 265 ° C in 1.5 hours, maintained at 265 At °C, it takes 1 hour. Then, 6 g of a mixture containing 2 g of 1,4-butanediamine and 6 g of 1,6-hexanediamine (which was maintained at 60 ° C) was added at 265 ° C for 1 hour. After a further 2 hours at 265 ° C, the reactor contents were cooled from 265 ° C to temperatures below 50 ° C in 110 minutes. The yield was 263.0 g (95.3% theoretical maximum yield) of powdered material. The product had a BET value of 1.7 and a particle size distribution with d10 = 50.5 microns, d50 = 146 microns and d90 = 572 microns, and a span of 2.30. Other analysis results are shown in Table 2.

Example VII-b: Synthesis of a polymer from the 66/6T salt of Example VII in a stirred reactor

Repeat the procedure of Example II-b except that 300 grams of the 66/6T salt of Example VII was used and the reactor contents were made from 25 within 3 hours. °C heated to 220 ° C, maintained at 220 ° C, took 3 hours, heated to 250 ° C in 5 hours, maintained at 250 ° C, took 5 hours, then cooled the reactor contents from 250 ° C in 110 minutes To a temperature below 50 °C. The product formed (268 g, 97.1% theoretical yield) consisted of a micro-colored powdery material. The results of these analyses are shown in Table 2.

Example VIII-b: 4T/6T with 80% diamine

The procedure of Example II-b was repeated except that 300 g of the 4T/6T salt of Example VIII was used. After 1 hour at 260 ° C, the reaction mixture was cooled to 230 ° C, at which temperature 26.6 g (0.23 mol) of 1,6-hexanediamine and 11.0 g (0.13 mol) were dispensed within 30 minutes. a mixture of 1,4-butanediamine. After the partitioning step was completed, the reaction mixture was heated to 240 ° C and maintained at this temperature for 2 hours. The reaction mixture was cooled to 230 ° C and a mixture of 13.3 g (0.115 mol) of 1,6-hexanediamine and 5.8 g (0.065 mol) of 1,4-diaminobutane was partitioned over 15 minutes. After the dispensing step was completed, the reaction mixture was heated to 240 ° C and maintained at this temperature for 6 hours, then the reactor contents were cooled to a temperature below 50 ° C over 2 hours. The product formed consists of a microcolored powdered material. The results of these analyses are shown in Table 2.

Example IX: Salt for granulation experiments

Three batches of salt particles of Example IX were collected and charged into a 100 liter double drum dryer equipped with a condenser and an inert gas inlet. The dryer was returned to normal pressure by additionally using a 10 mbar absolute vacuum and nitrogen flushing. The dryer was gradually heated from room temperature to 170 ° C under normal pressure under a nitrogen atmosphere for 3 hours, further heated to 190 ° C in 7 hours, and further heated to 20 hours. 260 ° C, and the drum dryer kept rotating. Water discharged from the polycondensation reaction is removed via the gas phase and collected in the condenser. No adhesion of the particles was observed during the heat treatment method. The results of these analyses are shown in Table 2.

Example X: Salt method and synthesis of polyamine 6T/4T (61/39 mol/mole) in a stirred reactor

The salt production process and the polymerization reaction were carried out in a two-layer, one-liter electric heating metal reactor. The reactor is equipped with a spiral stirring device, an inert gas inlet, and an outlet for leaving the inert gas and condensed gas out of the reactor, and a thermometer for measuring the reactor wall and the contents of the reactor. 183.63 grams of solid p-citric acid (1.106 moles) powder was charged to the reactor. The pair of citric acid powders were stirred and flushed with 5 grams of nitrogen per hour to inertize the reactor contents within 3 hours. The reactor contents were continuously stirred and subjected to a constant rotation at 75 rpm for an additional step while continuing the nitrogen purge. The reactor contents were heated from 25 ° C to 65 ° C in 30 minutes by using a programmed temperature profile and monitoring the temperature of the reactor contents in the powder bed to heat the reactor contents. 40.01 g of 1,4-butanediamine (0.454 mol) was prepared by melting and mixing the diamine in a batching vessel at 65 ° C (which is equal to the dispensing temperature of the diamine mixture (65 ° C)). And a liquid mixture of 81.37 grams of 1,6-hexanediamine (0.700 mole). The liquid mixture was added dropwise to the bed of the p-citric acid powder at a compounding rate of 0.42 mol%/min, and the reactor contents were maintained at a temperature below 85 °C. After the dispensing step was completed, the reactor contents were maintained at a temperature of 85 ° C for a period of 120 minutes. Thereafter, the reactor contents were heated from 85 ° C to 245 ° C in 180 minutes, then Heat from 245 ° C to 260 ° C in 90 minutes. This temperature was maintained at 260 ° C and took 90 minutes. The reactor contents were then cooled from 260 ° C to temperatures below 50 ° C in 110 minutes. The product formed (257 g, 97% theoretical maximum yield) consisted of a micro-colored powder material. The results of the analysis are shown in Table 2.

Comparative Experiment CE-B-b: Synthesis of 6T/4T Salt Synthetic Polymer from CE-A in a Stirred Reactor

The procedure of Example II-b was repeated except that the 6T/4T salt was used in combination with 300 grams of CE-B. When 238 ° C was reached, the experiment was aborted due to high torque formation and the reactor contents were cooled to a temperature below 50 ° C in 110 minutes.

For the experiments according to the invention, no gel was found in the viscosity measurements. The paper-based gel is meant the presence of insoluble particles when the polymer is dissolved in a Typical solvents (e.g. H ₂ SO ₄₎ within which the insoluble particles present in the solution viscosity can not be measured reliably.

Example XI: Kinetics of Direct Solid State Polymerization of 6T/4T Salts of Example IV

Six grams of the salt powder of Example IV was placed in a 40 microliter aluminum DSC sample crucible without a pin and having a pre-perforated lid (50 micron holes). The sample crucible was placed on a Mettler TGA-DSC 1 automated system. The furnace of the instrument is cooled by a constant temperature water bath system. The TGA-DSC 1 furnace of this instrument was flushed with anhydrous nitrogen at a flow rate of 50 ml/min. The nitrogen flow is maintained at the local level during subsequent heating and cooling steps. The powder was heated to 150 ° C at a rate of 15 ° C per minute. This temperature was maintained at 150 ° C for 5 minutes and then heated to 260 ° C at a rate of 1 ° C per minute. This temperature was maintained at 260 ° C for 4 hours and then cooled to room temperature. 140 minutes after the start of the heating protocol, a loss rate of 8.1% by weight, which corresponds to a conversion of 61%, was found.

Example XII: Kinetics of Direct Solid State Polymerization of 4T Salt of Example III

The procedure of Example XI was repeated except that the salt powder of Example III was used in place of the salt powder of IV. 140 minutes after the start of the heating protocol, a loss rate of only 2.8% by weight was found, which corresponds to a conversion of 20%.

The above Examples XI and XII show that the formation rate of a copolyamide is significantly faster than the formation of a homopolymer by using the method according to the invention. Thus, the process of the invention is particularly suitable for the preparation of copolymerized guanamines.

Claims (20)

A process for preparing a semi-crystalline semi-aromatic polyamine from a diamine and a dicarboxylic acid, comprising: (i) dispensing a liquid diamine to a stirred powder containing an aromatic dicarboxylic acid to form a diamine-containing a powder of a /dicarboxylate (DD salt), and (ii) solid state polymerization of the DD salt to obtain the polyamine; wherein the diamine comprises a mixture of at least two aliphatic diamines. The method of claim 1, wherein the diamine is distributed at a distribution rate of up to 4 mol% per minute relative to the molar amount of the dicarboxylic acid. The method of claim 1, wherein the powder from the step (i) is subjected to solid state forming, and then the step (ii) is carried out. The method of claim 1, wherein the aromatic dicarboxylic acid is selected from the group consisting of p-citric acid, 2,6-naphthalenedicarboxylic acid, and biphenyl-4,4'-dicarboxylic acid, or a combination thereof. The method of claim 1, wherein the agitated powder further comprises an aliphatic dicarboxylic acid selected from the group consisting of adipic acid and cyclohexanedicarboxylic acid. The method of claim 1, wherein the diamine comprises an aliphatic diamine selected from the group consisting of C2-C10 diamines. The method of claim 1, wherein the aromatic dicarboxylic acid comprises at least 50 mol% relative to the total moles of the dicarboxylic acid contained in the stirred powder. The method of claim 7, wherein the aromatic dicarboxylic acid comprises at least 80 mol% relative to the total moles of the dicarboxylic acid contained in the stirred powder. The method of claim 1, wherein the dicarboxylic acid comprises an aromatic dicarboxylic acid selected from the group consisting of p-citric acid, 2,6-naphthalenedicarboxylic acid, and biphenyl-4,4' dicarboxylic acid, and The liquid diamine comprises a mixture comprising at least two aliphatic diamines selected from the group consisting of C2-C10 diamines. The method of claim 9, wherein the at least two aliphatic diamines are selected from the group consisting of 1,4-butanediamine, 1,6-hexanediamine, and 1,10-decanediamine. The method of claim 1, wherein the step (ii) comprises a two-step process: (ii-a) obtained in the condensation step (i) at a first condensation temperature (Tc1) of at least 10 ° C below the melting point of the DD salt. The DD salt to produce a solid prepolymer; and (ii-b) a second condensation temperature (Tc2) further at least 15 ° C below the melting temperature of the prepolymer to be obtained and the melting temperature of the polyamide The solid prepolymer from step (ii-a) is condensed to obtain the polycondensate in a solid state. The method of claim 1, wherein the semicrystalline semi-aromatic polyamine has a melting temperature of at least 280 °C. The method of claim 1, wherein the DD salt has a melting temperature of at least 240 °C. The method of claim 11, wherein the prepolymer has a viscosity value of at least 10 ml/g before performing step (ii-b). The method of claim 11, wherein the dicarboxylic acid comprises at least 90 mole % of citric acid relative to the total moles of the dicarboxylic acid, and the liquid is two relative to the total moles of the diamines The amine comprises at least 80 mole % of a C2-C10 diamine. The method of claim 15, wherein the liquid diamine comprises a mixture comprising at least two aliphatic diamines selected from the group consisting of C2-C10 diamines. The method of claim 11, wherein during the condensation step (ii-b), a supplemental diamine is added. The method of any one of claims 1 to 17, wherein the polyamine has at least one of the methods according to ISO 307, fourth edition and determined in 96% sulfuric acid (0.005 g/ml) at 25 ° C. Viscosity value of 20 ml / gram. The method of claim 18, wherein the polyamine has a viscosity of at least 50 ml/g as measured in 96% sulfuric acid (0.005 g/ml) according to ISO 307, fourth edition at 25 ° C. . A semi-crystalline semi-aromatic copolyamine powder obtained by the method of any one of claims 1 to 19, wherein the powder has a BET value of at least 0.4 m ² /g, and at least 50 μm a granular material composed of medium-sized (d50) particles, the BET value being determined by a method according to ISO 9277:2010, which is subjected to laser granulometry according to the method of ISO 13320 at 20 ° C. Determination.