WO2015080425A1 - Polyamide resin and polyamide molded body using same - Google Patents

Abstract

A polyamide resin, according to the present invention, is formed through polycondensation of a monomer comprising 1,4-cyclohexanedicarboxylic acid, 1,10-decandiamine, and 1,12-dodecandiamine, wherein the molar ratio of 1,10-decandiamine and 1,12-dodecandiamine is approximately 10:90 to approximately 65:35. As a result, the polyamide resin capable of enabling high durability and color stability in the polyamide molded body can be provided.

Description

Polyamide Resin and Polyamide Molded Product Using the Same

The present invention relates to a polyamide resin and a polyamide molded article using the same. In more detail, this invention relates to the polyamide resin which can exhibit high heat-resistant color stability in a polyamide molded object.

Polyamide resins are widely used as textiles for garments, industrial materials, engineering plastics, and the like, due to their excellent properties and ease of melt molding. In recent years, the polyamide resin used in the fields of electrical / electronic parts, automobile parts, reflective materials, and the like has been required to have more excellent physical properties and functions. In particular, the development of polyamide resins and molded articles that can be used for the use of components such as reflective materials, which are difficult to discolor under high temperature conditions, and which have excellent heat-color stability.

Polyamide resin is generally manufactured by polycondensation reaction of dicarboxylic acid and diamine. For example, Patent Document 1 contains polyamides containing mainly 1,4-cyclohexanedicarboxylic acid units as dicarboxylic acid units and mainly containing aliphatic diamine units having 4 to 18 carbon atoms as diamine units. Disclosed is a reflector for an LED using a polyamide composition. Specifically, Patent Literature 1 polycondenses 1,4-cyclohexanedicarboxylic acid and 1,11-undecanediamine in the presence of sodium hypophosphite monohydrate to obtain a lower order condensate (prepolymer). The polyamide resin produced is described. However, the injection molded article described in Patent Document 1 hardly has a high level of heat-resistant color stability to a desired degree, and further improvement is required.

(Prior art document)

(Patent Document 1) WO2011 / 027562 A Pamphlet

An object of this invention is to provide the polyamide resin which can exhibit high heat-resistant color stability in a polyamide molded object.

MEANS TO SOLVE THE PROBLEM The present inventors earnestly researched in order to solve the said subject. In the process, in the case of using 1,4-cyclohexanedicarboxylic acid as the dicarboxylic acid, 1,11- by using 1,10-decanediamine and 1,12-dodecanediamine in a predetermined ratio as the diamine. It turned out that melting | fusing point of the obtained polyamide resin falls rather than using only undecanediamine. And the polyamide molded object using this polyamide resin found that heat-resistant color stability improved significantly compared with the conventional molded object, and came to complete this invention.

That is, the polyamide resin of the present invention is obtained by polycondensing a monomer containing 1,4-cyclohexanedicarboxylic acid and 1,10-decanediamine and 1,12-dodecanediamine. And the molar ratio of 1,10-decanediamine to 1,12-dodecanediamine is about 10:90 to about 65:35.

Embodiments of the present invention, in a polyamide molded body, can provide a polyamide resin capable of exhibiting high heat-resistant color stability.

EMBODIMENT OF THE INVENTION Hereinafter, although embodiment of this invention is described, this invention should be defined by a claim, and is not limited only to the following forms. In this specification, "X to Y" which shows a range means "X or more and Y or less."

<Polyamide resin>

Polyamide resin according to an embodiment of the present invention, 1,4-cyclohexanedicarboxylic acid; and a monomer comprising 1,10-decanediamine and 1,12-dodecanediamine; By polycondensation. And the molar ratio of 1,10-decanediamine to 1,12-dodecanediamine is about 10:90 to about 65:35.

The polyamide resin has a lower melting point than the conventional polyamide resin disclosed in Patent Document 1, and has a higher heat-resistant color stability when used as a molded body. The mechanism by which such excellent heat-resistant color stability is exhibited is not clear, but the present inventors speculate as follows. In addition, this invention is not limited to the following mechanism.

As described in Patent Literature 1, when the polyamide molded body is used as the LED reflecting plate, the LED reflecting plate is exposed to a high temperature exceeding 100 ° C by light irradiation of the LED. In such high temperature use, the problem that the brightness fall by the reflectance fall by the discoloration of resin itself cannot be suppressed has been pointed out previously. The present inventors assume that the discoloration of the resin at the time of high temperature use under such an atmosphere is due to deterioration in the molded body, and it is thought that the cause of the deterioration may be due to heat deterioration during molding. It was.

In molding methods such as injection molding, in order to lower the viscosity of the polyamide resin at the time of molding, it is necessary to heat-melt the polyamide resin at a temperature about 10 ° C. above the melting point. Since the polyamide resin of this embodiment has a melting point lower than that of the conventional polyamide resin, the polyamide resin of the present embodiment can be molded at a lower temperature. Therefore, heat deterioration at the time of shaping | molding can be suppressed more, and as a result, it is estimated that high heat-resistant color stability is exhibited. Hereinafter, the polyamide resin of this form is demonstrated.

Dicarboxylic acid

In this aspect, the dicarboxylic acid used as a raw material of a polyamide resin contains 1, 4- cyclohexanedicarboxylic acid as essential. Moreover, in one Example, you may further contain other dicarboxylic acid other than 1, 4- cyclohexanedicarboxylic acid as a monomer of a raw material. However, from a viewpoint of fully exhibiting the effect of this invention, the ratio of 1, 4- cyclohexanedicarboxylic acid is about 50 mol% or more, about 75 mol% or more, about 90 mol with respect to the total amount of the dicarboxylic acid contained in a monomer. Or at least about 95 mol% or at least about 100 mol%. Within this range, the polyamide resin can exhibit high heat color stability.

The other dicarboxylic acid is not particularly limited, but, for example, terephthalic acid, malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, pimelic acid, 2,2-dimethyl Glutaric acid, 3,3-diethylsuccinic acid, suberic acid, 1,3-cyclopentanedicarboxylic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedi Carboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, diphenic acid, 4,4'-oxydibenzoic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenyl Sulfone-4,4'-dicarboxylic acid, 4,4'-biphenyldicarboxylic acid, etc. are mentioned. These other dicarboxylic acids may be used individually by 1 type, and may be used in combination of 2 or more type. Moreover, you may use together a small amount of polyhydric carboxylic acid components, such as trimellitic acid, trimesic acid, a pyromellitic acid, as needed.

Diamine

The diamine used as a raw material of a polyamide resin contains 1,10-decanediamine and 1,12-dodecanediamine, and the mol ratio of 1,10-decanediamine and 1,12-dodecanediamine (1 , 10-decanediamine: 1,12-dodecanediamine) is from about 10:90 to about 65:35 or from about 15:85 to about 60:40. The mol ratio may be more specifically about 30:70 to about 50:50 or about 35:65 to about 45:55. By using 1,10-decanediamine and 1,12-dodecanediamine in the above ratios, the melting point of the polyamide resin can be significantly lowered as compared with the case of using only conventional 1,11-undecanediamine. . As a result, it becomes possible to exhibit high heat-resistant color stability in a polyamide molded object. The reason why the melting point of the polyamide resin decreases in this way is not clear, but the present inventors set the copolymer using the specific diamine of 1,10-decanediamine and 1,12-dodecanediamine to make 1,11- It is thought that melting | fusing point was reduced as a result of the cohesion force of molecular chains falling and it being difficult to take a crystal structure rather than using only undecanediamine.

Moreover, in this aspect, you may contain other diamines other than 1,10-decanediamine and 1,12- dodecanediamine as a monomer of a raw material. However, from the viewpoint of fully exhibiting the effects of the present invention, the ratio of the total amount of 1,10-decanediamine and 1,12-dodecanediamine is about 90 mol% or more with respect to the total amount of diamine contained in the monomer, About 95 mol% or more, about 98 mol% or more, about 100 mol%. Within this range, the effect of lowering the melting point can be improved.

The other diamine is not particularly limited, but may be an aliphatic alkylene diamine having 4 to 25 carbon atoms. Specifically, 1,4-butanediamine, 1,6-hexanediamine (hexamethylenediamine), 1,7-heptane diamine, 1,8-octanediamine, 1,9-nonanediamine, 1,11-Undecanediamine, 2-methyl-1,5-pentanediamine, 3-methyl-1,5-pentanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2 , 4,4-trimethyl-1,6-hexanediamine, 2-methyl-1,8-octanediamine, etc. are mentioned.

Moreover, as a specific example of diamines other than aliphatic alkylene diamine of 4-25 carbon atoms, ethylenediamine and propanediamine; Cyclohexanediamine, methylcyclohexanediamine, isophoronediamine, bis (4-aminocyclohexyl) methane, 1,3-bisaminomethylcyclohexane, 1,4-bisaminomethylcyclohexane, norbornanedimethanamine Alicyclic diamines such as tricyclodecane dimethanamine; And aromatic diamines such as paraphenylenediamine, metaphenylenediamine, xylylenediamine, 4,4'-diaminodiphenylsulfone, and 4,4'-diaminodiphenyl ether. Moreover, the term xylylenediamine includes three isomers, ortho xylylenediamine, metaxylylenediamine (MXDA), and paraxylylenediamine (PXDA). Other diamines other than these 1,10-decanediamine and 1,12-dodecanediamine may be used individually by 1 type, and may be used in combination of 2 or more type.

In one embodiment, as described above, 1,4-cyclohexanedicarboxylic acid is used as the dicarboxylic acid, and 1,10-decanediamine and 1,12-dodecanediamine are used as the diamine in a predetermined ratio. By doing so, a polyamide resin having a low melting point can be obtained. Specifically, the melting point of the polyamide resin of the present form may be about 285 ℃ to 305 ℃, about 285 ℃ to about 300 ℃ or about 285 ℃ to about 295 ℃. By using such low melting polyamide resin, the heat-resistant color stability after shaping | molding can be improved significantly.

<Method for producing polyamide resin>

The polyamide resin of one embodiment is prepared by polycondensation of a monomer comprising a dicarboxylic acid and a diamine described above. There is no restriction | limiting in particular in polycondensation method, What is necessary is just to select suitably from arbitrary methods conventionally known. For example, after heating the aqueous solution of dicarboxylic acid and diamine at high temperature and high pressure, and carrying out a dehydration reaction, or polycondensing dicarboxylic acid and diamine under pressurized heating conditions, and obtaining a lower condensate, the lower condensation is carried out. The method of making water high molecular weight by arbitrary methods, such as solution polymerization, melt polymerization, and solid state polymerization, etc. are mentioned. Among them, the polycondensation of dicarboxylic acid and diamine may yield a lower order condensate, and then the lower order condensation may be high molecular weight by solid phase polymerization.

That is, the method for producing a polyamide resin according to an embodiment of the present invention, the above-mentioned 1,4-cyclohexanedicarboxylic acid; and a monomer comprising 1,10-decanediamine and 1,12-dodecanediamine Polycondensation, and (1) obtaining a lower order condensate, and the process (2) of carrying out the solid state polymerization of a lower order condensate. Hereinafter, the manufacturing method of the polyamide resin of this form is demonstrated for every process.

Process (1)

The low-order condensate is synthesized by injecting an aqueous solution of the monomer or salt and the like into a pressurized polymerization tank which is usually used, for example, and performing a polycondensation reaction in an aqueous solvent under stirring conditions.

An aqueous solvent is a solvent which has water as a main component. The solvent used in addition to water is not particularly limited as long as it does not affect polycondensation reactivity or solubility. Specific examples include alcohols such as methanol, ethanol, propanol, butanol and ethylene glycol. .

The amount of water in the reaction system at the start of the polycondensation reaction is not particularly limited as long as the amount of water in the reaction system at the end of the reaction is from about 20% by mass to about 35% by mass, for example, from about 20% by mass to about 60% by mass. To%. By setting the amount of water to about 20% by mass or more, it is possible to form a uniform solution when starting the polycondensation reaction. Moreover, by making it about 60 mass% or less, the time and energy which distills water off in a polycondensation process can be reduced, and reaction time is also shortened, and the influence of thermal deterioration can be made small.

In this step, a phosphorus catalyst can be used in terms of increasing the polycondensation rate and preventing deterioration during the polycondensation reaction. As the phosphorus catalyst, hypophosphite, phosphate, hypophosphorous acid, phosphoric acid, phosphate ester, polymethaic acid, polyphosphate, phosphine oxide, phosphonium halogen compound and the like can be used. In embodiments, hypophosphite, phosphate, hypophosphorous acid, phosphoric acid may be used. As hypophosphite, for example, sodium hypophosphite, potassium hypophosphite, calcium hypophosphite, magnesium hypophosphite, aluminum hypophosphite, vanadium hypophosphite, manganese hypophosphite, zinc hypophosphite, lead hypophosphite, nickel hypophosphite, hypophosphite Cobalt, ammonium hypophosphite and the like can be used. More specifically, sodium hypophosphite, potassium hypophosphite, calcium hypophosphite, magnesium hypophosphite may be used. As the phosphate, for example, sodium phosphate, potassium phosphate, potassium dihydrogen phosphate, calcium phosphate, vanadium phosphate, magnesium phosphate, manganese phosphate, lead phosphate, nickel phosphate, cobalt phosphate, ammonium phosphate, diammonium phosphate or the like can be used. have. As phosphate ester, ethyl octadecyl phosphate etc. are mentioned as an example. Examples of the polymetaphosphates include sodium trimethaphosphate, sodium pentametaphosphate, sodium hexametaphosphate, and polymetaphosphate. As polyphosphoric acid, sodium tetrapolyphosphate etc. are mentioned as an example. Examples of the phosphine oxides include hexamethylphosphoamide and the like. Moreover, the form of these compound hydrates may be sufficient.

The addition amount of a phosphorus catalyst may be about 0.0001 mass part to about 5 mass parts, or about 0.001 mass part to about 1 mass part with respect to 100 mass parts of total amounts of a monomer. Within this range, the effect of increasing the polycondensation rate and preventing degradation during the polycondensation reaction can be exerted. In addition, the addition time may be any time until the completion of the solid phase polymerization, but may be from the time of raw material injection to the completion of the polycondensation of the lower condensate. Moreover, you may add multiple times. Furthermore, you may add in combination of 2 or more types of other phosphorus catalysts.

Moreover, this process can perform the said polycondensation reaction in presence of an end sealing agent. When the terminal sealant is used, the molecular weight adjustment of the lower order condensate becomes easier, and the melt stability of the lower order condensate is improved. The terminal sealing agent is not particularly limited as long as it is a monofunctional compound having reactivity with the terminal amino group or the terminal carboxyl group in the lower condensate, and specifically, acid anhydrides such as monocarboxylic acid, monoamine, and phthalic anhydride, and monoisocyanate. Nate, monoacid halide, monoester, monoalcohol, etc. are mentioned. Among them, monocarboxylic acid or monoamine may be used as the end sealant in view of reactivity and stability of the sealing end, and in addition to the above characteristics, monocarboxylic acid may be used in view of ease of handling.

The monocarboxylic acid used as the terminal sealant is not particularly limited as long as it is a monocarboxylic acid having reactivity with an amino group. For example, aliphatic mono, such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecyl acid, myristic acid, palmitic acid, stearic acid, pivalic acid, isobutyl acid, etc. Carboxylic acid; Alicyclic monocarboxylic acids such as cyclohexane carboxylic acid; Aromatic monocarboxylic acids, such as benzoic acid, toluic acid, (alpha)-naphthalene carboxylic acid, (beta)-naphthalene carboxylic acid, methylnaphthalene carboxylic acid, and phenylacetic acid, or arbitrary mixtures thereof are mentioned. Among them, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecyl acid, myristic acid, palmitic acid, stearic acid, etc. Acids and benzoic acids can be used. The monoamine used as the terminal sealant is not particularly limited as long as it is a monoamine having reactivity with a carboxyl group. For example, aliphatic monoamines, such as methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, and dibutylamine; Alicyclic monoamines such as cyclohexylamine and dicyclohexylamine; Aromatic monoamines, such as aniline, toluidine, diphenylamine, and naphthylamine, or arbitrary mixtures thereof are mentioned. Especially, butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline can be used from a viewpoint of reactivity, a boiling point, stability of a sealing terminal, cost, etc.

The amount of the end sealant used in preparing the lower condensate may vary depending on the reactivity of the end sealant used, the boiling point, the reaction apparatus, the reaction conditions, and the like, but is generally about 0.1 mol to the number of moles of dicarboxylic acid or diamine. It can be used within the range of% to about 15 mol%.

The synthesis of the lower order condensate in this step is usually performed by raising the temperature and increasing the pressure under stirring conditions. The polymerization temperature is controlled after the injection of the raw material. In addition, the polymerization pressure is controlled in accordance with the progress of the polymerization.

The reaction temperature in this process may be about 200 ° C to about 260 ° C or about 210 ° C to about 250 ° C. By making reaction temperature about 200 degreeC or more, reaction rate can be made quick and the molecular weight of a lower order condensate can fully be raised. On the other hand, by setting the reaction temperature to about 260 ° C. or less, it is possible to prevent the color of the polyamide from deteriorating due to excessive thermal history.

The reaction pressure in this process may be about 0.5 MPa to about 5 MPa or about 1 MPa to about 4.5 MPa. The polycondensation reaction proceeds while distilling off a large amount of water, but by controlling the reaction pressure to be about 0.5 MPa or more, it is easy to control the temperature in the reaction system and the amount of water in the reaction system. In addition, since the lower condensate can be prevented from becoming a low moisture content or cooled by the latent heat of evaporation of water, it can be prevented from becoming difficult to discharge. On the other hand, when it is set to about 5 MPa or less, since it is not necessary to use the reaction apparatus with high pressure resistance, it is not necessary to increase cost. Moreover, since the moisture content in a reaction system does not become high too much, the polymerization degree of a lower order condensate can be raised.

The reaction time in the present process may be about 0.5 hours to about 4 hours or about 1 hour to about 3 hours. Reaction time here means the time required from reaching the said reaction temperature to starting discharge operation. When the reaction time is about 0.5 hours or more, a sufficient reaction rate is reached, and unreacted substances do not remain, so that a lower order condensate with a uniform property can be obtained. On the other hand, by setting it as about 4 hours or less, it is possible to prevent the application of excessive heat history, and furthermore, even if the reaction time is extended from this, no further effect of high polymerization can be obtained.

The amount of water in the reaction system at the end of the reaction of the lower order condensate in this step may be about 15% by mass to about 35% by mass or about 20% by mass to about 35% by mass. The reaction completion time here is a low-order condensate that has reached a predetermined degree of polymerization, and indicates the time point at which the discharge operation is started, and the condensed water generated during the reaction is also the sum of the moisture content. The amount of water can be adjusted to be the amount of injected water added to the amount of condensed water generated, or a predetermined amount of water can be adjusted by distilling off the reaction pressure in an apparatus equipped with a condenser and a pressure regulating valve. By setting the amount of water in the reaction system at the end of the reaction to about 15% by mass or more, the lower condensate can be prevented from being precipitated or solidified in the reaction system and can be easily discharged. On the other hand, by making it about 35 mass% or less, the low order condensate of sufficient polymerization degree can be obtained. In addition, since the amount of water to be evaporated and separated at the time of discharge cannot increase the discharge rate, or the need for drying treatment before the solid phase polymerization is unlikely to occur, deterioration in manufacturing efficiency can be prevented.

In this process, the polycondensation reaction for obtaining a low order condensate may be performed batchwise, or may be performed continuously. Moreover, the polycondensation reaction for producing a low-order condensate can be performed with stirring, from the point of prevention of adhesion of a lower-order condensate to a reaction container, the uniform progress of a polycondensation reaction, etc.

The low-order condensate obtained by this process has a logarithmic viscosity (IV) measured at a temperature of 25 ° C. at a concentration of 0.5 g / dl in concentrated sulfuric acid, from about 0.07 dl / g to about 0.40 dl / g or about 0.10 dl / g About 0.25 μs / g. In addition, the specific measuring method of the logarithmic viscosity (IV) is demonstrated in the Example mentioned later. If the logarithmic viscosity (IV) is about 0.07 dl / g or more, since the low melting point is small, it is possible to prevent the resin powder from fusion or adhesion in the apparatus during solid phase polymerization. On the other hand, if the logarithmic viscosity (IV) is about 0.40 dl / g or less, the problem that the discharge becomes difficult because precipitation and solidification in the reaction system at the time of preparation of the lower order condensate can be prevented.

In addition, before the polymerization of the lower condensate, a salt control step and / or a concentration step may be added if necessary. Salt control is a process which produces | generates a salt from a dicarboxylic acid component and a diamine component, and can adjust it in the range of about 0.5 of the neutralization point of a salt, or the range of about 0.3 of the neutralization point of a salt. In the concentration, the concentration of the raw material injection concentration can be concentrated to a concentration of about + 2% by mass to about + 90% by mass or to a concentration of about + 5% by mass to about + 80% by mass. The concentration process may be about 90 ° C. to about 220 ° C., about 100 ° C. to about 210 ° C., about 130 ° C. to about 200 ° C. The pressure in the concentration process is, for example, about 0.1 MPa to about 2.0 MPa. Usually, the pressure of concentration is controlled below the pressure of polymerization. In addition, in order to promote the concentration, for example, forced discharge may be performed by nitrogen gas flow or the like. The concentration step is effective for shortening the polymerization time.

Moreover, after polycondensation reaction, you may provide the process of discharge | release and cooling a lower order condensate as needed. Extraction of the lower condensate from the reaction vessel is performed by extracting the lower condensate from the reaction vessel under an inert gas atmosphere (for example, under a nitrogen atmosphere) at a pressure below atmospheric pressure. According to this discharging method, it is not necessary to use a pressure vessel for taking out at a predetermined pressure, and furthermore, no effort is required to take out the lower condensate from the reaction vessel while supplying steam separately into the reaction vessel, and thermal deterioration is caused. It is possible to obtain a low order condensate in a small, non-foamed granule form (powder form or granule form) that is small, has a logarithmic viscosity sufficiently high, and has a high volume specific gravity.

The inert gas atmosphere may have an oxygen concentration of about 1% by volume or less from the viewpoint of preventing oxidative degradation of the lower condensate.

The discharge rate of the lower order condensate from the reaction vessel can be appropriately adjusted according to the size of the reaction vessel, the amount of contents in the reaction vessel, the temperature, the size of the ejection opening, the length of the ejection nozzle portion, and the like. In general, however, it can be taken out so that the discharge rate per outlet cross-sectional area is in the range of about 2000 kg / s / m 2 to about 20000 kg / s / m 2. If it is this range, the volume density of the lower-order condensate obtained will be in the range of about 0.35 g / cm <3> to about 0.8 g / cm <3>, for example, collapse | disintegration | flocculation, aggregation, fusion to the reactor wall, etc. in the process of solid-state polymerization mentioned later. This is unlikely to occur, excellent in handleability, and can be filled in a polymerization apparatus or the like, and the volumetric efficiency can be improved in the apparatus used in the solid phase polymerization step.

In addition, since the temperature of the low-order condensate taken out from the reaction vessel immediately drops to, for example, about 100 ° C. or lower due to latent heat of evaporation of water at the time of taking out, thermal deterioration and deterioration by oxygen hardly occur.

In addition, since the lower condensate discharged evaporates most of the accompanying moisture by the latent heat of the lower condensate, cooling and drying are simultaneously performed. It is preferable to increase the efficiency of drying and cooling by discharging one of an inert gas such as nitrogen or a reduced pressure than atmospheric pressure. In addition, by installing a cyclone-type solid-gas separation device as the discharge container, not only can the out-of-system scattering of powder be prevented during discharge, but also the discharge treatment can be performed under a high gas flux, so that drying and cooling efficiency can be improved. It is preferable to become.

Moreover, you may further perform the rolling process and granulation process for making the volume specific gravity of the lower order condensate obtained above, or to match a particle diameter as needed.

<Solid state polymerization>

Process (2)

In this step, the low-order condensate obtained in the step (1) is subjected to solid phase polymerization to obtain a polyamide resin.

In this process, even if it carries out as it was taken out from the reaction container of a lower condensate, after carrying out drying of the lower condensate taken out from the reaction container, the solid state polymerization taken out from the reaction container was once stored. You may carry out afterward or you may perform after the said powder compacting process or granulation process to the low order condensate taken out from the reaction container. When high polymerization degree is carried out by solid state polymerization, polyamide resin with less thermal degradation can be obtained.

The polymerization method and conditions for solid-phase polymerization of the lower condensate are not particularly limited, and any method and conditions capable of performing high polymerization while maintaining a solid state without causing fusion, aggregation, or deterioration of the lower condensate are You can do it.

However, in order to prevent oxidative deterioration of the lower condensate and the resulting polyamide, solid phase polymerization can be carried out in an inert gas atmosphere such as helium gas, argon gas, nitrogen gas, carbon dioxide gas or under reduced pressure.

The temperature of the solid phase polymerization is not particularly limited, but the maximum reaction temperature is, for example, about 170 ° C to about 260 ° C, about 200 ° C to about 250 ° C, or about 220 ° C to about 240 ° C. The maximum reaction temperature need not be at the end of the solid phase polymerization, and may be reached at any point in time until the end of the solid phase polymerization.

There is no restriction | limiting in particular about the apparatus of solid state polymerization used at this process, Any well-known apparatus can be used. As a specific example of a solid-state polymerization apparatus, For example, a uniaxial disk type, a kneading machine, a biaxial paddle type, a vertical tower type apparatus, a vertical tower type apparatus, a rotary drum type, or a double vulcan type solid state polymerization apparatus, a drying apparatus, etc. Can be mentioned.

The reaction time of the solid phase polymerization is not particularly limited, but may usually be about 1 hour to about 20 hours. During the solid state polymerization reaction, the lower order condensate may be mechanically stirred or may be stirred with a gas stream.

According to the manufacturing method as described above, a polyamide resin excellent in heat-color stability can be obtained with almost no production problem such as gelation.

<Polyamide molded article and manufacturing method thereof>

The polyamide resin mentioned above is provided to uses, such as an electrical / electronic component, an automotive component, a reflective material, etc. through a shaping | molding process. That is, according to another aspect of the present invention, there is provided a polyamide molded body formed by molding the polyamide resin; There is provided a method for producing a polyamide molded article, comprising the step (3) of molding the polyamide resin. Hereinafter, the polyamide molded body of this embodiment and its manufacturing method are demonstrated.

Although the shaping | molding method in the shaping | molding process of one Example is not restrict | limited, Since the polyamide resin which concerns on this invention mentioned above has low melting | fusing point, heating at the temperature exceeding about 320 degreeC is unnecessary, Since the deterioration of the heat-resistant color by this can be reduced, the shaping | molding method which requires heating (melting) more than melting | fusing point is suitable. As a molding method, injection molding, blow molding, extrusion molding, compression molding, etc. are mentioned, for example. Among them, the injection molding method may be used, that is, the polyamide resin molded body may be an injection molded body. In the injection molding method, it is possible to use a metal mold in accordance with the shape of the resin molded article, thereby producing a resin molded article having a complicated shape.

The molding temperature in molding the polyamide resin is not particularly limited, but may be about 320 ° C. or less, about 305 ° C. or less, about 300 ° C. or less, or about 295 ° C. or less. If the molding temperature is about 320 ° C. or lower, thermal degradation of the polyamide resin can be suppressed, and deterioration of color can be prevented even when the molded body is used under high temperature conditions thereafter. In addition, the shaping | molding temperature here means the temperature of polyamide resin, and the upper limit shall refer to the highest temperature among the temperatures of the polyamide resin of the whole molding process. On the other hand, the lower limit of the molding temperature is not particularly limited as long as it is a moldable temperature that is higher than the melting point of the polyamide resin. However, the lower limit temperature of the molding temperature is usually about + 5 ° C and may be about + 8 ° C or more.

In addition, the molding process may be performed in a non-oxidizing atmosphere. In this specification, a non-oxidizing atmosphere shall mean the atmosphere whose content of a non-oxidizing gas is about 95 volume% or more. For example, it points out under an oxygen free atmosphere whose content of non-oxidizing gas is about 100 volume%. Examples of the non-oxidizing atmosphere include an inert gas atmosphere or a reducing gas atmosphere. Here, the inert gas is not particularly limited, but helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), nitrogen (N ₂ ), or the like can be used. The inert gas may be used alone or in the form of two or more mixed gases. Moreover, you may mix a reducing gas in an inert gas. The reducing gas is not particularly limited, but may be a hydrogen (H ₂ ) gas or a carbon monoxide (CO) gas. In particular, an inert gas can be used from the viewpoint of safety.

The polyamide molded body may contain optional additive components in addition to the polyamide resin described above. As the additive component, for example, filler materials such as titanium oxide, titanium dioxide, titanium trioxide, zinc oxide, zirconium oxide, zinc sulfide, various fiber materials such as glass fiber, carbon fiber, inorganic powder filler, organic powder filler Antioxidants, heat stabilizers (hindered phenols, hydroquinones, phosphites and their substituents, copper compounds, etc.), weathering agents (resolcinols, salicylates, benzotriazoles, benzophenones, Hindered amines, etc.), release agents and lubricants (montanic acid and its metal salts, esters thereof, half esters, stearyl alcohols, stearamides, various bisamides, bisurea and polyethylene waxes, etc.), pigments (cadmium sulfide, phthalo Cyanine, carbon black, etc.), dyes (nigrosin, etc.), crystal nucleating agents (talc, silica, kaolin, clay, etc.), plasticizers (octyl p-oxybenzoate, N-butylbenzenesulfonamide, etc.), antistatic (Alkyl sulfate type anionic antistatic agent, nonionic antistatic agent such as polyoxyethylene sorbitan monostearate, betaine positive antistatic agent, etc.), flame retardant (e.g. red phosphorus, melamine cyanurate, magnesium hydroxide, hydroxide) Hydroxides such as aluminum, ammonium polyphosphate, brominated polystyrene, brominated polyphenylene ether, brominated polycarbonates, brominated epoxy resins or combinations thereof with brominated flame retardants and antimony trioxide, and other polymers (olefins, modified polyolefins, Olefin copolymers such as ethylene methyl acrylate, ethylene ethyl acrylate copolymer, ethylene propylene copolymer, ethylene-1-butene copolymer, olefin copolymers such as propylene-1-butene copolymer, polystyrene, fluorine resin , Silicone resin, LCP (Liquid Crystal Polymer) and the like.

Although content of the said addition component in a polyamide molded object depends on the use and function which a molded object is used, it is usually about 0 mass part-about 150 mass parts with respect to 100 mass parts of polyamide resin, and about 0 mass part- About 100 parts by mass.

The polyamide molded body can be used for electric and electronic parts, automobile parts, reflective materials and the like. In particular, since the discoloration is suppressed even when used under a long time of high temperature conditions, the polyamide molded article of the present invention can be used for the use of a reflecting plate. As a specific example, it can use as a reflecting plate for light emitting devices, such as various electrical and electronic components, indoor lighting, ceiling lighting, outdoor lighting, automobile lighting, display equipment, and headlights. Among them, since LEDs are often under a high temperature environment around 100 ° C due to high brightness and high output, sufficient luminance can be maintained by using the polyamide molded body of the present embodiment having improved heat color as the LED reflector.

Example

This invention is demonstrated in more detail using the following example and a comparative example. However, the technical scope of the present invention is not limited only to the following examples. In addition, evaluation of algebraic viscosity (IV), melting point and color, and discoloration resistance test were performed by the following method.

(1) Algebraic viscosity (IV)

A sample solution was prepared by dissolving the sample in a concentration of 0.5 g / dl in 96% concentrated sulfuric acid. 96% concentrated sulfuric acid (blank) and the sample solution were measured at the temperature of 25 degreeC using the Uberode viscous tube, and the fall second was measured and it calculated by the following formula (1).

[Equation 1]

η _inh = ln (η _rel ) / c

In Equation 1, η _rel = t1 / t0,

t1: number of seconds to drop the sample,

t0: number of seconds of the blank to fall,

c: concentration of solution (g / dl).

(2) melting point

Using differential scanning calorimetry (DSC) manufactured by Seiko Instruments Co., Ltd., the sample in an amorphous state was flowed under nitrogen at a flow rate of 10 ml / min, and the temperature was raised from 30 to 350 ° C. at a heating rate of 10 ° C./min. It hold | maintained for a minute, it measured to 100 degreeC at the temperature-fall rate of 10 degree-C / min, measured the glass transition temperature, and measured the endothermic peak temperature by melting at the time of temperature rising as melting | fusing point.

(3) color

The measurement was carried out using a compact colorimeter NW-11 manufactured by Nippon Denshoku Kogyo Co., Ltd.

Illumination and reception conditions: 45 ° circular illumination, 0 ° reception

Measuring method: diffraction grating, back spectroscopy

Measuring area: 10 mmφ, Light source: Puls Xenon lamp

Measuring light source, observation conditions: D65 / 2 °

Measured item: Yellowness (YI).

(4) Discoloration resistance test (heat color stability)

The molded object was heat-processed in 170 degreeC and 8 hours in air atmosphere in the heating oven, the color before and behind a process was measured, and the color fading resistance (heat color stability) was evaluated.

Example 1

<Production of Polyamide Resin>

As raw materials, 186.22 g (1.082 mol) of 1,4-cyclohexanedicarboxylic acid, 94.60 g of 1,10-decanediamine (0.549 mol = 50 mol%), and 110.00 g of 1,12-dodecanediamino (0.549 mol = 50) Mol%), benzoic acid 3.96 g (0.032 mol), sodium hypophosphite monohydrate (SHM) 0.376 g (3.55 mmol, 0.1 mass part with respect to the injection raw material), and 126 g (20 mass% with respect to the injection raw material), It injected | thrown-in to the internal volume 1L autoclave reaction tank provided with an accumulator, a pressure regulating valve, and a bottom discharge valve, and performed nitrogen substitution. It heated up to 200 degreeC over 2 hours, stirring. The internal pressure of the reaction vessel at this time was 2 MPa. Next, the reaction was continued for 2 hours while the internal temperature was maintained at 215 ° C, and water was distilled off to maintain the internal pressure of the reaction tank at 2 MPa. Thereafter, the internal pressure was lowered to 1.2 MPa over 30 minutes, and the resulting lower condensate was discharged from the bottom discharge valve to a receiver under atmospheric pressure at atmospheric temperature (25 ° C.) under nitrogen flow to obtain a white, powdery form. Lower order condensates were obtained.

300 g of the obtained lower condensate was injected into a 1000 ml round bottom flask, installed in a rotary evaporator with an oil bath, and after nitrogen replacement, the flask was immersed in an oil bath while rotating the flask under nitrogen flow at 1 L / min, and the internal temperature was decreased. After heating up to 230 degreeC over 1 hour, solid-state polymerization reaction was continued at the same temperature for 5 hours. After the predetermined reaction time had elapsed, the mixture was cooled to room temperature (25 ° C) to obtain a highly polymerized polyamide resin.

<Production of Polyamide Molded Body>

The said polyamide resin was shape | molded on condition of the following, and the polyamide molded object was obtained.

Using a SE SE18DUZ, an injection molding machine manufactured by Sumitomo Jukikai Co., Ltd., a test specimen (size 80 mm x 10 mm x 4.0 mm) in the shape of a tanzaku was used under the conditions shown below. Produced.

In-cylinder atmosphere: nitrogen (N ₂ ) or atmosphere (air)

Polyamide resin temperature in the cylinder: the temperature shown in Table 1 below

Mold temperature: 150 ℃

Injection pressure: 120 MPa to 140 MPa

Injection speed: 30 mm / sec

Screw speed: 150rpm

Cooling time: 45 seconds.

Examples 2 to 7, Comparative Examples 1 to 5

The polyamide resins and polyamides of Examples 2 to 7 and Comparative Examples 1 to 5 in the same manner as in Example 1, except that the monomers in Example 1 were changed to the compounds and compounding ratios of Table 1 below. A molded article was prepared.

The results are shown in Tables 1 and 2.

Table 1

-	-	Example
-	-	One	2	3	4	5	6	7
Monomer: Dicarboxylic acid (mol%)	1,4-CHDA	100	100	100	100	100	100	100
	TPA	-	-	-	-	-	-	-
Monomer: diamine (mol%)	1,10-DDA	50	30	65	10	45	35	40
	1,11-UDDA	-	-	-	-	-	-	-
	1,12-DDDA	50	70	35	90	55	65	60
Physical Properties of Polyamide Resin	Ⅳ (g / dL)	0.92	0.87	0.93	0.91	0.90	0.91	0.92
	Melting point (℃)	297	296	305	305	293	293	287
Polyamide molded article (1) Molding under N 2 atmosphere	Molding temperature (℃)	330	330	330	330	315	315	310
	Discoloration test: YI (initial)	-46.3	-46.9	-46.1	-46.5	-46.2	-46.4	-46.9
	Discoloration resistance test: YI (170 degrees Celsius, 8h later)	5.7	5.5	7.4	7.3	4.3	4.0	3.1
Polyamide molded article (2) Molding in air atmosphere	Molding temperature (℃)	-	-	-	-	-	315	310
	Discoloration test: YI (initial)	-	-	-	-	-	-46.4	-46.9
	Discoloration resistance test: YI (170 degrees Celsius, 8h later)	-	-	-	-	-	9.2	8.1

TABLE 2

-	-	Comparative example
-	-	One	2	3	4	5
Monomer: Dicarboxylic acid (mol%)	1,4-CHDA	100	100	-	-	100
	TPA	-	-	100	100	-
Monomer: Diamine (mol%)	1,10-DDA	70	100	-	100	-
	1,11-UDDA	-	-	-	-	100
	1,12-DDDA	30	-	100	-	-
Physical Properties of Polyamide Resin	Ⅳ (g / dL)	0.97	0.98	0.92	0.92	0.95
	Melting point (℃)	317	336	297	320	306
Polyamide molded article (1) Molding under N 2 atmosphere	Molding temperature (℃)	340	340	310	340	320
	Discoloration test: YI (initial)	-46.8	Molding impossible	-19.2	3.2	-19.2
	Discoloration resistance test: YI (170 degrees Celsius, 8h later)	12.8	-	19.1	44.6	10.3
Polyamide molded article (2) Molding in air atmosphere	Molding temperature (℃)	-	-	310	-	-
	Discoloration test: YI (initial)	-	-	-17.8	-	-
	Discoloration resistance test: YI (170 degrees Celsius, 8h later)	-	-	25.3	-	-

1,4-CHDA: 1,4-cyclohexanedicarboxylic acid

TPA: terephthalic acid

1,10-DDA: 1,10-decanediamine

1,11-UDDA: 1,11-undecandiamine

1,12-DDDA: 1,12-dodecanediamine

As shown in Table 1, 1,4-cyclohexanedicarboxylic acid is included as the dicarboxylic acid, and 1,10-decanediamine and 1,12-dodecanediamine are used as the diamine from about 10:90 to about 65:35. The polyamide resins of Examples 1 to 7 obtained by condensation polymerization of a monomer containing (mol ratio) had a low melting point, and showed that a molded article formed by molding the polyamide resin had high heat-resistant color stability.

In particular, Examples 1, 2, and 5 to 7 containing 1,10-decanediamine and 1,12-dodecanediamine in a ratio of about 30:70 to about 50:50 (mol ratio) have a melting point of about 305 ° C or less. Low melting point, especially in the range of about 35:65 to about 45:55 (mol ratio), Examples 7-7 had a low melting point below about 300 ° C. Corresponding to this, the YI of the polyamide molded body 1 at 170 ° C for 8 hours is about 5.7 or less in Examples 1, 2, and 5 to 7 and about 4.3 or less in Examples 5 to 7, and thus, thermal color stability. It showed that it improves more than this.

Moreover, from the contrast of YI after 170 degreeC and 8 hours of a polyamide molded object, the polyamide molded object 1 shape | molded in the nitrogen atmosphere which is a non-oxidizing gas is more than the polyamide molded object 2 which shape | molded in air atmosphere, It was shown that the heat-resistant color stability is excellent.

On the other hand, as shown in Table 2, it was found that the polyamide resin and the molded article obtained in Comparative Examples 1 to 5 in which the composition of the monomer was outside the range of the present invention did not have desired performance (formability, heat-resistant color stability). .

From the above result, it turned out that according to this invention, the polyamide resin which can exhibit high heat-resistant color stability in a polyamide molded object can be provided.

Claims (8)

1,4-cyclohexanedicarboxylic acid; And

Monomers comprising 1,10-decanediamine and 1,12-dodecanediamine; As a polyamide resin formed by polycondensation,

And wherein the molar ratio of said 1,10-decanediamine to said 1,12-dodecanediamine is from about 10:90 to about 65:35.

The polyamide resin of claim 1 wherein the molar ratio of 1,10-decanediamine to 1,12-dodecanediamine is from about 30:70 to about 50:50.

The polyamide resin of claim 1, wherein the molar ratio of the 1,10-decanediamine and the 1,12-dodecanediamine is about 35:65 to about 45:55.

The polyamide molded article formed by shape | molding the polyamide resin in any one of Claims 1-3 at about 320 degrees C or less.

The polyamide molded article formed by shape | molding the polyamide resin in any one of Claims 1-3 at about 320 degrees C or less in non-oxidizing atmosphere.

As a manufacturing method of the polyamide resin as described in any one of Claims 1-3,

Polycondensing the monomer to obtain a lower order condensate; And

The manufacturing method of polyamide resin containing the process (2) of carrying out the solid state polymerization of the said lower order condensate.

The polyamide molded object containing the process (3) which shape | molds the polyamide resin in any one of Claims 1-3, or the polyamide resin obtained by the manufacturing method of Claim 6 at about 320 degrees C or less. Method of preparation.

The method for producing a polyamide molded article according to claim 7, wherein the step (3) is performed under a non-oxidizing atmosphere.