JP2020029539A - Polyamide composition - Google Patents

Abstract

To provide a polyamide composition having more excellent various physical properties and excellent flame retardancy.SOLUTION: There is provided a polyamide composition which comprises a polyamide (A) having a dicarboxylic acid unit and a diamine unit and a halogen-based flame retardant (B), wherein more than 40 mol% and 100 mol% or less of the dicarboxylic acid unit is a naphthalenedicarboxylic acid unit, 60 mol% or more and 100 mol% or less of the diamine unit is a branched aliphatic diamine unit and a linear aliphatic diamine unit of an optional constitutional unit and the ratio of the branched aliphatic diamine unit to 100 mol% in total of the branched aliphatic diamine unit and the linear aliphatic diamine unit is 60 mol% or more.SELECTED DRAWING: None

Description

  The present invention relates to a polyamide composition and the like. More specifically, the present invention relates to a semi-aromatic polyamide having a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of an aliphatic diamine unit, and a polyamide composition containing a halogen-based flame retardant.

  Semi-aromatic polyamides using aromatic dicarboxylic acids such as terephthalic acid and aliphatic diamines, and crystalline polyamides such as nylon 6, nylon 66, etc., are suitable for clothing due to their excellent properties and ease of melt molding. Widely used as fibers for industrial and industrial materials and general-purpose engineering plastics. On the other hand, these crystalline polyamides have also been pointed out with problems such as insufficient heat resistance and poor dimensional stability due to water absorption. In particular, in recent years, resinization of engine room components has been actively studied for the purpose of improving fuel efficiency of automobiles, and is superior to conventional polyamides in high-temperature strength, heat resistance, dimensional stability, mechanical properties, and physical and chemical properties. Polyamides are desired.

  As a polyamide having excellent heat resistance, for example, Patent Document 1 discloses a semi-aromatic polyamide obtained from 2,6-naphthalenedicarboxylic acid and a linear aliphatic diamine having 9 to 13 carbon atoms. Patent Document 1 describes that the semi-aromatic polyamide is excellent not only in heat resistance but also in chemical resistance and mechanical properties. On the other hand, Patent Literature 1 describes that use of an aliphatic diamine having a side chain is not preferable because crystallinity of the obtained polyamide is reduced.

Patent Document 2 discloses that 60 to 100 mol% of dicarboxylic acid units are composed of 2,6-naphthalenedicarboxylic acid units, and 60 to 100 mol% of diamine units are 1,9-nonanediamine units and 2-methyl-1,8. A polyamide comprising -octanediamine units and having a molar ratio of 1,9-nonanediamine units to 2-methyl-1,8-octanediamine units of 60:40 to 99: 1 is disclosed. Patent Document 2 describes that the polyamide is excellent in mechanical properties, thermal decomposition resistance, low water absorption, chemical resistance, and the like, in addition to heat resistance.
Furthermore, a resin composition containing a semi-aromatic polyamide and uses of the semi-aromatic polyamide are disclosed (for example, Patent Documents 3 and 4).

JP-A-50-67393 JP-A-9-12715 International Publication No. 2012/098840 International Publication No. 2005/102681

As described above, conventional polyamides such as Patent Documents 1 and 2 have physical properties such as heat resistance, mechanical properties, low water absorption, and chemical resistance, and further improvement in these physical properties is required.
Patent Literature 2 describes that 1,9-nonanediamine and 2-methyl-1,8-octanediamine are used in combination as aliphatic diamines. However, 2-methyl-1,8-octanediamine having a side chain is described. No mention is made of polyamides in the high ratio region.

  Therefore, an object of the present invention is to provide a polyamide composition which is excellent in various physical properties and is excellent in flame retardancy, and a molded article comprising the same.

The present inventors have conducted intensive studies and as a result, a specific polyamide having a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of a branched aliphatic diamine unit, and a polyamide composition containing a halogen-based flame retardant. The present inventors have found that a product can solve the above-mentioned problem, and have further studied based on the findings to complete the present invention.
That is, the present invention is as follows.

[1] A polyamide (A) having a dicarboxylic acid unit and a diamine unit, and a halogen-based flame retardant (B),
Naphthalenedicarboxylic acid units account for more than 40 mol% and 100 mol% or less of the dicarboxylic acid units,
60 mol% or more and 100 mol% or less of the diamine unit are a branched aliphatic diamine unit and a linear aliphatic diamine unit of an optional constitutional unit, and the branched aliphatic diamine unit and the linear aliphatic diamine A polyamide composition, wherein the proportion of the branched aliphatic diamine unit to the total 100 mol% of the units is 60 mol% or more.
[2] A molded article comprising the polyamide composition.

  ADVANTAGE OF THE INVENTION According to this invention, the polyamide composition excellent in various physical properties and also excellent in flame retardance, and the molded article which consists of this can be provided.

For polyamides in which the dicarboxylic acid unit is a 2,6-naphthalenedicarboxylic acid unit and the diamine unit is a 1,9-nonanediamine unit and / or a 2-methyl-1,8-octanediamine unit, the 2-methyl- It is the graph which plotted the melting point (degreeC) of polyamide with respect to the content rate (mol%) of a 1,8-octanediamine unit.

  Hereinafter, the present invention will be described in detail. In the present specification, a rule that is preferable can be arbitrarily adopted, and a combination of preferable ones is more preferable. In this specification, the description “XX to YY” means “XX or more and YY or less”.

<Polyamide composition>
The polyamide composition of the present invention contains a polyamide (A) having a dicarboxylic acid unit and a diamine unit, and a halogen-based flame retardant (B).
In the present specification, “to unit” (where “to” indicates a monomer) means “constituent unit derived from”, and for example, “dicarboxylic acid unit” refers to “derived from dicarboxylic acid”. "Structural unit" means, and "diamine unit" means "structural unit derived from diamine".

[Polyamide (A)]
The polyamide (A) contained in the polyamide composition of the present invention has a dicarboxylic acid unit and a diamine unit. And, more than 40 mol% and 100 mol% or less of the dicarboxylic acid units are naphthalenedicarboxylic acid units. Further, 60 mol% or more and 100 mol% or less of the diamine unit are a branched aliphatic diamine unit and a linear aliphatic diamine unit of an optional constitutional unit, and the branched aliphatic diamine unit and the linear aliphatic diamine The proportion of the branched aliphatic diamine unit to the total of 100 mol% with the aliphatic diamine unit is 60 mol% or more.

  As described above, the polyamide (A) has a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of a branched aliphatic diamine unit, and thus has various chemical resistance and other properties. The polyamide composition of the present invention, which is excellent in physical properties and contains the polyamide (A) and the halogen-based flame retardant, also maintains the above-mentioned excellent properties, and additionally has excellent flame retardancy. In addition, various molded articles obtained from the polyamide composition can maintain excellent properties of the polyamide composition.

Generally, physical properties such as high-temperature strength, mechanical properties, heat resistance, low water absorption, and chemical resistance that a polyamide can have tend to be superior as the crystallinity of the polyamide increases. Further, between polyamides having similar primary structures, the melting point of the polyamide tends to increase as the crystallinity of the polyamide increases. Here, regarding the melting point of the polyamide, for example, a polyamide in which the diamine unit is a 1,9-nonanediamine unit and / or a 2-methyl-1,8-octanediamine unit and the dicarboxylic acid unit is a terephthalic acid unit is taken as an example. And a graph showing the relationship between the melting point of the polyamide (vertical axis) and the composition of diamine units (content ratio of 1,9-nonanediamine unit and 2-methyl-1,8-octanediamine unit) (horizontal axis). Indicates a minimal part. Then, the melting points at both ends on the horizontal axis of the graph, that is, the melting point A1 when the 1,9-nonanediamine unit having a linear structure is 100 mol%, and 100 mol of 2-methyl-1,8-octanediamine unit having a branched structure. %, The melting point A1 is usually higher than the melting point B1 depending on the molecular structure of the diamine unit.
On the other hand, in the case of a polyamide in which the diamine unit is a 1,9-nonanediamine unit and / or a 2-methyl-1,8-octanediamine unit and the dicarboxylic acid unit is a 2,6-naphthalenedicarboxylic acid unit, While a minimal portion is shown in a graph having the same vertical axis and horizontal axis as the above, the melting point A2 when 1,9-nonanediamine unit having a linear structure is 100 mol%, and 2-methyl-1 having a branched structure are shown. In comparison with the melting point B2 when the octanediamine unit was 100 mol%, it was found that the melting point B2 was unexpectedly higher than the melting point A2.

Specifically, for a polyamide in which the dicarboxylic acid unit is a 2,6-naphthalenedicarboxylic acid unit and the diamine unit is a 1,9-nonanediamine unit and / or a 2-methyl-1,8-octanediamine unit, FIG. 1 shows a graph in which the melting point (° C.) of the polyamide is plotted against the content ratio (mol%) of the 2-methyl-1,8-octanediamine unit.
According to FIG. 1, 2-methyl-1,8-octanediamine unit is 0 mol% (that is, 1,9-nonanediamine unit is 100 mol%). -It can be seen that the melting point of the polyamide decreases as the content ratio of the octanediamine unit increases. On the other hand, from the vicinity where the content of the 2-methyl-1,8-octanediamine unit exceeds 50 mol%, it can be seen that the melting point of the polyamide significantly increases as the content increases. Comparing the melting points near both ends on the horizontal axis in FIG. 1, the melting point when the content of the 2-methyl-1,8-octanediamine unit in the branched structure is around 100 mol% is more linear. It can be seen that the melting point is higher than the melting point when the content of 1,9-nonanediamine units in the structure is 100 mol%. The melting points in the left and right regions of the portion other than the vicinity of both ends on the horizontal axis are also compared with the vicinity of the vicinity where the content ratio of 2-methyl-1,8-octanediamine unit is 50 mol%. It can be seen that the melting point tends to be higher in the right region where the content of -1,8-octanediamine unit is high than in the left region where the content of 1,9-nonanediamine unit is high.

  As described above, it has been found that the polyamide having a diamine unit mainly composed of 1,9-nonanediamine unit and / or 2-methyl-1,8-octanediamine unit has different physical properties depending on the dicarboxylic acid unit to be combined. . As a result of further study by the present inventors, when the content ratio of the branched aliphatic diamine unit is larger than that of the linear aliphatic diamine unit, by adopting a naphthalenedicarboxylic acid unit as the dicarboxylic acid unit, the resistance to naphthalenedicarboxylic acid is improved. It has been found that various physical properties such as chemical properties are further improved, and that a halogen-based flame retardant described below is further included, whereby the flame retardancy is further excellent. The reason for this is not necessarily clear, but it is presumed that the appropriate proportion of the branched structure in the diamine unit in the polyamide and the presence of the naphthalene skeleton in the dicarboxylic unit are interrelated.

(Dicarboxylic acid unit)
Of the dicarboxylic acid units, more than 40 mol% and not more than 100 mol% are naphthalenedicarboxylic acid units. When the content of the naphthalenedicarboxylic acid unit in the dicarboxylic acid unit is 40 mol% or less, various physical properties such as the chemical resistance of the polyamide composition are improved, and the flame retardancy due to the inclusion of the halogen-based flame retardant. Expression becomes difficult.
From the viewpoints of mechanical properties, heat resistance, and chemical resistance, the content of the naphthalenedicarboxylic acid unit in the dicarboxylic acid unit is preferably 50 mol% or more, more preferably 60 mol% or more, and 70 mol% or more. More preferably, it is at least 80 mol%, even more preferably at least 80 mol%, even more preferably at least 90 mol%, particularly preferably at least 100 mol%.

Examples of the naphthalenedicarboxylic acid unit include 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, And structural units derived from naphthalenedicarboxylic acids such as 2,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid. Can be These structural units may be included alone or in combination of two or more. Among the above naphthalenedicarboxylic acids, 2,6-naphthalenedicarboxylic acid is preferred from the viewpoint of the chemical resistance and flame retardancy of the polyamide composition and the reactivity with diamine.
From the same viewpoint as described above, the content of the structural unit derived from 2,6-naphthalenedicarboxylic acid in the naphthalenedicarboxylic acid unit is preferably 90 mol% or more, more preferably 95 mol% or more. , And 100 mol% (substantially 100 mol%).

The dicarboxylic acid unit can include a structural unit derived from a dicarboxylic acid other than naphthalenedicarboxylic acid, as long as the effects of the present invention are not impaired.
Examples of the other dicarboxylic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, dimethylmalonic acid, and dimethylmalonic acid. Aliphatic dicarboxylic acids such as 1,2-diethylsuccinic acid, 2,2-dimethylglutaric acid, 2-methyladipic acid and trimethyladipic acid; 1,3-cyclopentanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, Alicyclic dicarboxylic acids such as 4-cyclohexanedicarboxylic acid, cycloheptanedicarboxylic acid, cyclooctanedicarboxylic acid and cyclodecanedicarboxylic acid; terephthalic acid, isophthalic acid, diphenic acid, 4,4′-biphenyldicarboxylic acid, diphenylmethane-4, 4'-dicarboxylic acid, diphenylsul And aromatic dicarboxylic acids such as down-4,4'-dicarboxylic acid. One of these structural units derived from other dicarboxylic acids may be contained, or two or more of them may be contained.
The content of the structural unit derived from the other dicarboxylic acid in the dicarboxylic acid unit is preferably 50 mol% or less, more preferably 40 mol% or less, and still more preferably 30 mol% or less. , 20 mol% or less, even more preferably 10 mol% or less.

(Diamine unit)
As for the diamine unit, 60 mol% or more and 100 mol% or less are a branched aliphatic diamine unit and a linear aliphatic diamine unit of an optional constitutional unit. That is, the diamine unit contains a branched aliphatic diamine unit and does not contain a linear aliphatic diamine unit, or contains both a branched aliphatic diamine unit and a linear aliphatic diamine unit, and The total content of the branched aliphatic diamine unit and the linear aliphatic diamine unit as an optional constituent unit is 60 mol% or more and 100 mol% or less. When the total content of the branched aliphatic diamine unit and the linear aliphatic diamine unit in the diamine unit is less than 60 mol%, the polyamide composition exhibits various physical property improving effects such as chemical resistance and flame retardancy. It becomes difficult.
From the viewpoints of chemical resistance, mechanical properties, and heat resistance, the total content of the branched aliphatic diamine unit and the linear aliphatic diamine unit in the diamine unit is preferably 70 mol% or more, and is preferably 80 mol% or more. %, More preferably 90 mol% or more, and particularly preferably 100 mol%.
In the present specification, the term "branched aliphatic diamine" refers to a linear aliphatic chain having a carbon atom to which two amino groups are bonded, each having a carbon atom at both ends. Means an aliphatic diamine having a structure in which one or more hydrogen atoms of an aliphatic chain (assumed aliphatic chain) are substituted by a branched chain. That is, for example, 1,2-propanediamine _{(H 2 N-CH (CH} 3) -CH 2 -NH 2) as one of branched-chain hydrogen atom of 1,2-ethylene group as contemplated aliphatic chain Is classified as a branched aliphatic diamine in this specification.

In the diamine unit, the ratio of the branched aliphatic diamine unit to the total of 100 mol% of the branched aliphatic diamine unit and the linear aliphatic diamine unit is 60 mol% or more. When the proportion of the branched aliphatic diamine unit is less than 60 mol%, it is difficult to exhibit various physical property improving effects such as chemical resistance and flame retardancy of the polyamide composition.
From the viewpoint that various physical properties such as chemical resistance are easily improved, and the moldability of the polyamide composition is improved, the branched fat relative to the total of 100 mol% of the branched aliphatic diamine unit and the linear aliphatic diamine unit is used. The proportion of the aromatic diamine unit is preferably at least 65 mol%, more preferably at least 70 mol%, even more preferably at least 72 mol%, even more preferably at least 77 mol%. , 80 mol% or more, even more preferably 90 mol% or more. The ratio may be 100 mol%, but is preferably 99 mol% or less, 98 mol% or less, further preferably 95 mol% or less in consideration of moldability and availability of diamine. You may.

  The carbon number of the branched aliphatic diamine unit is preferably 4 or more, more preferably 6 or more, further preferably 8 or more, and preferably 18 or less, and 12 or less. Is more preferable. When the number of carbon atoms in the branched aliphatic diamine unit is within the above range, the polymerization reaction between the dicarboxylic acid and the diamine proceeds favorably, the crystallinity of the polyamide (A) also improves, and the polyamide composition containing the polyamide (A) The physical properties of the object are more easily improved. As an example of a preferred embodiment of the number of carbon atoms of the branched aliphatic diamine unit, the number of carbon atoms may be 4 to 18 or less, 4 to 12 or less, 6 to 18 or less, 6 to 12 or less, or 8 to 18 or less. , 8 or more and 12 or less.

The type of the branched chain in the branched aliphatic diamine unit is not particularly limited, and may be, for example, various aliphatic groups such as a methyl group, an ethyl group, and a propyl group. It is preferably a structural unit derived from a diamine having at least one selected from the group consisting of a methyl group and an ethyl group as a chain. When a diamine having at least one selected from the group consisting of a methyl group and an ethyl group is used as a branched chain, the polymerization reaction between the dicarboxylic acid and the diamine proceeds well, and the chemical resistance of the polyamide composition containing the polyamide (A) is improved. The property is easier to improve. From this viewpoint, the branched chain is more preferably a methyl group.
The number of the branched chains of the branched aliphatic diamine forming the branched aliphatic diamine unit is not particularly limited, but is preferably three or less because the effects of the present invention are more remarkably exhibited. , More preferably two or less, and even more preferably one.

  When the carbon atom to which any one of the amino groups is bonded is placed at position 1, the branched aliphatic diamine unit has a 2-position carbon atom adjacent thereto (a carbon atom on the assumed aliphatic chain) and the 2-position carbon atom. Is preferably a structural unit derived from a diamine having at least one of the branched chains on at least one of the carbon atoms at the 3-position adjacent to the carbon atom (the carbon atom on the assumed aliphatic chain). More preferably, it is a structural unit derived from a diamine having at least one of the branched chains at the carbon atom. Thereby, various physical properties such as chemical resistance and flame retardancy of the polyamide composition are more easily improved.

Examples of the branched aliphatic diamine unit include 1,2-propanediamine, 1-butyl-1,2-ethanediamine, 1,1-dimethyl-1,4-butanediamine, and 1-ethyl-1,4-diamine. Butanediamine, 1,2-dimethyl-1,4-butanediamine, 1,3-dimethyl-1,4-butanediamine, 1,4-dimethyl-1,4-butanediamine, 2-methyl-1,3- Propanediamine, 2-methyl-1,4-butanediamine, 2,3-dimethyl-1,4-butanediamine, 2-methyl-1,5-pentanediamine, 3-methyl-1,5-pentanediamine, 2 , 5-dimethyl-1,6-hexanediamine, 2,4-dimethyl-1,6-hexanediamine, 3,3-dimethyl-1,6-hexanediamine, 2,2-dimethyl-1,6-hexane Amine, 2,4-diethyl-1,6-hexanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, 2-ethyl-1 , 7-Heptanediamine, 2-methyl-1,8-octanediamine, 3-methyl-1,8-octanediamine, 1,3-dimethyl-1,8-octanediamine, 1,4-dimethyl-1,8 -Octanediamine, 2,4-dimethyl-1,8-octanediamine, 3,4-dimethyl-1,8-octanediamine, 4,5-dimethyl-1,8-octanediamine, 2,2-dimethyl-1 , 8-Octanediamine, 3,3-dimethyl-1,8-octanediamine, 4,4-dimethyl-1,8-octanediamine, 2-methyl-1,9-nonanediamine, 5-methyl 1,9 structural units derived from branched aliphatic diamines, and the like. These structural units may be included alone or in combination of two or more.
Among the branched aliphatic diamine units, 2-methyl-1,5-pentanediamine, 3-methyl-1,2-methyl-1,5-pentanediamine is preferred from the viewpoints that the effects of the present invention are more remarkably exhibited and the raw material availability is excellent. Structural units derived from at least one diamine selected from the group consisting of 5-pentanediamine, 2-methyl-1,8-octanediamine and 2-methyl-1,9-nonanediamine are preferred, and 2-methyl-1 Structural units derived from 8,8-octanediamine are more preferred.

The carbon number of the linear aliphatic diamine unit is preferably 4 or more, more preferably 6 or more, still more preferably 8 or more, and preferably 18 or less, and 12 or less. More preferably, there is. When the number of carbon atoms in the linear aliphatic diamine unit is within the above range, the polymerization reaction between the dicarboxylic acid and the diamine proceeds well, the crystallinity of the polyamide becomes good, and the physical properties of the polyamide are easily improved. As an example of a preferred embodiment of the number of carbon atoms of the linear aliphatic diamine unit, the number of carbon atoms may be 4 to 18 or less, 4 to 12 or less, 6 to 18 or less, 6 to 12 or less, or 8 to 18 or less. It may be 8 or more and 12 or less.
The carbon number of the linear aliphatic diamine unit and the number of carbon atoms of the above-mentioned branched aliphatic diamine unit may be the same or different, but are the same since the effects of the present invention are more remarkably exhibited. It is preferable that

Examples of the linear aliphatic diamine unit include ethylenediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, 1,13-tridecanediamine, 1,14-tetradecanediamine, 1, Structural units derived from linear aliphatic diamines such as 15-pentadecanediamine, 1,16-hexadecanediamine, 1,17-heptadecanediamine, and 1,18-octadecanediamine. These structural units may be included alone or in combination of two or more.
Among the above-mentioned linear aliphatic diamine units, the effects of the present invention are more remarkably exhibited, and from the viewpoint of improving the heat resistance of the obtained polyamide composition containing polyamide (A), 1,4-butane is particularly preferred. Diamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,11-undecanediamine, And a structural unit derived from at least one diamine selected from the group consisting of 1,12-dodecanediamine, and a structural unit derived from 1,9-nonanediamine is more preferable.

The diamine unit may include a structural unit derived from a diamine other than the branched aliphatic diamine and the linear aliphatic diamine as long as the effects of the present invention are not impaired. Examples of the other diamine include an alicyclic diamine and an aromatic diamine.
Examples of the alicyclic diamine include cyclohexanediamine, methylcyclohexanediamine, isophoronediamine, norbornanedimethylamine, and tricyclodecanedimethyldiamine.
As the aromatic diamine, for example, p-phenylenediamine, m-phenylenediamine, p-xylylenediamine, m-xylylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylsulfone, 4,4 '-Diaminodiphenyl ether and the like.
One of these structural units derived from other diamines may be contained, or two or more of them may be contained.
The content of the structural unit derived from the other diamine in the diamine unit is preferably at most 30 mol%, more preferably at most 20 mol%, further preferably at most 10 mol%.

(Dicarboxylic acid unit and diamine unit)
The molar ratio of dicarboxylic acid units to diamine units [dicarboxylic acid units / diamine units] in the polyamide (A) is preferably 45/55 to 55/45. When the molar ratio of the dicarboxylic acid unit to the diamine unit is in the above range, the polymerization reaction proceeds favorably, and a polyamide composition excellent in desired physical properties is easily obtained.
The molar ratio between the dicarboxylic acid unit and the diamine unit can be adjusted according to the mixing ratio (molar ratio) of the raw material dicarboxylic acid and the raw material diamine.

  The total ratio of dicarboxylic acid units and diamine units in the polyamide (A) (the ratio of the total number of moles of dicarboxylic acid units and diamine units to the number of moles of all the constituent units constituting the polyamide (A)) is 70 mol% or more. It is preferably at least 80 mol%, more preferably at least 90 mol%, even more preferably at least 95 mol%, and even more preferably at least 100 mol%. When the total ratio of the dicarboxylic acid unit and the diamine unit is in the above range, a polyamide composition having more desirable physical properties can be obtained.

(Aminocarboxylic acid unit)
The polyamide (A) may further include an aminocarboxylic acid unit in addition to the dicarboxylic acid unit and the diamine unit.
Examples of the aminocarboxylic acid unit include lactams such as caprolactam and lauryl lactam; and structural units derived from aminocarboxylic acids such as 11-aminoundecanoic acid and 12-aminododecanoic acid. The content of the aminocarboxylic acid unit in the polyamide (A) is preferably 40 mol% or less, more preferably 20 mol% or less, based on 100 mol% in total of the dicarboxylic acid unit and the diamine unit constituting the polyamide (A). Is more preferable.

(Polyvalent carboxylic acid unit)
In the polyamide (A), a range in which a structural unit derived from a trivalent or higher polycarboxylic acid such as trimellitic acid, trimesic acid, and pyromellitic acid can be melt-molded within a range that does not impair the effects of the present invention. Can also be included.

(Terminal sealant unit)
The polyamide (A) may contain a structural unit derived from a terminal blocking agent (terminal blocking unit).
The terminal blocking agent unit is preferably at least 1.0 mol%, more preferably at least 1.2 mol%, and preferably at least 1.5 mol%, based on 100 mol% of the diamine unit. Is more preferably 10 mol% or less, more preferably 7.5 mol% or less, and even more preferably 6.5 mol% or less. When the content of the terminal blocking agent unit is in the above range, a polyamide composition having excellent mechanical strength and fluidity is obtained. The content of the terminal capping agent unit can be adjusted to the above-mentioned desired range by appropriately adjusting the amount of the terminal capping agent at the time of charging the polymerization raw material. In consideration of the volatilization of the monomer component during the polymerization, fine adjustment of the charged amount of the terminal blocking agent is performed so that a desired amount of the terminal blocking agent unit is introduced into the obtained polyamide (A). Is desirable.
As a method for obtaining the content of the terminal blocking agent unit in the polyamide (A), for example, as described in JP-A-7-228690, the solution viscosity is measured, and the viscosity of the solution is compared with the number average molecular weight. A method of calculating the total terminal group amount from the relational expression and subtracting the amino group amount and the carboxyl group amount determined by titration from the relational expression, or a signal corresponding to each of the diamine unit and the terminal blocking agent unit using ¹ H-NMR. And the like, and the latter is preferable.

  As the terminal blocking agent, a monofunctional compound having reactivity with a terminal amino group or a terminal carboxyl group can be used. Specific examples include monocarboxylic acids, acid anhydrides, monoisocyanates, monoacid halides, monoesters, monoalcohols, and monoamines. From the viewpoints of reactivity and the stability of the capped end, a terminal capping agent for a terminal amino group is preferably a monocarboxylic acid, and a terminal capping agent for a terminal carboxyl group is preferably a monoamine. From the viewpoint of ease of handling and the like, a monocarboxylic acid is more preferable as the terminal blocking agent.

  The monocarboxylic acid used as the terminal blocking agent is not particularly limited as long as it has reactivity with an amino group, and for example, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid Aliphatic monocarboxylic acids such as acids, tridecanoic acid, myristic acid, palmitic acid, stearic acid, pivalic acid and isobutyric acid; cycloaliphatic monocarboxylic acids such as cyclopentanecarboxylic acid and cyclohexanecarboxylic acid; benzoic acid, toluic acid, Aromatic monocarboxylic acids such as α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, and phenylacetic acid; and arbitrary mixtures thereof. Among them, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid are preferred from the viewpoints of reactivity, sealed terminal stability, and price. And at least one selected from the group consisting of benzoic acid and benzoic acid.

  The monoamine used as the terminal blocking agent is not particularly limited as long as it has reactivity with a carboxyl group. For example, methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearyl Aliphatic monoamines such as amine, dimethylamine, diethylamine, dipropylamine and dibutylamine; alicyclic monoamines such as cyclohexylamine and dicyclohexylamine; aromatic monoamines such as aniline, toluidine, diphenylamine and naphthylamine; arbitrary mixtures thereof; Can be mentioned. Among these, at least one selected from the group consisting of butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline from the viewpoints of reactivity, high boiling point, stability of a sealed terminal, and price. Is preferred.

The polyamide (A) preferably has an intrinsic viscosity [η _inh ] of 0.1 dl / g or more, measured at a concentration of 0.2 g / dl and a temperature of 30 ° C., using concentrated sulfuric acid as a solvent, and 0.4 dl / g or more. Is more preferably 0.6 dl / g or more, particularly preferably 0.8 dl / g or more, and further preferably 3.0 dl / g or less, and 2.0 dl / g or less. / G or less, more preferably 1.8 dl / g or less. When the intrinsic viscosity [η _inh ] of the polyamide (A) is within the above range, various physical properties such as moldability are further improved. The intrinsic viscosity [η _inh ] is determined based on the flow time t ₀ (second) of the solvent (concentrated sulfuric acid), the flow time t ₁ (second) of the sample solution, and the sample concentration c (g / dl) in the sample solution (that is, 0.2 g). / Dl), it can be obtained by the relational expression of η _inh = [ln (t ₁ / t ₀ )] / c.

  The melting point of the polyamide (A) is not particularly limited, and may be, for example, 260 ° C. or higher, 270 ° C. or higher, and further 280 ° C. or higher. However, since the effects of the present invention are more remarkably exhibited, 290 ° C. ° C or higher, more preferably 295 ° C or higher, still more preferably 300 ° C or higher, even more preferably 305 ° C or higher, even more preferably 310 ° C or higher, It may be 315 ° C. or higher. The upper limit of the melting point of the polyamide (A) is not particularly limited, but is preferably 330 ° C. or lower, more preferably 320 ° C. or lower, further preferably 317 ° C. or lower in consideration of moldability and the like. . The melting point of the polyamide (A) can be determined as a peak temperature of a melting peak that appears when the temperature is raised at a rate of 10 ° C./min using a differential scanning calorimeter (DSC). It can be determined by the method described.

  The glass transition temperature of the polyamide (A) is not particularly limited, and may be, for example, 100 ° C. or higher, 110 ° C. or higher, and even 120 ° C. or higher, since the effects of the present invention are more remarkably exhibited. , 125 ° C. or higher, more preferably 130 ° C. or higher, still more preferably 135 ° C. or higher, even more preferably 137 ° C. or higher, even more preferably 138 ° C. or higher. Preferably, it may be 139 ° C. or higher. Although the upper limit of the glass transition temperature of the polyamide (A) is not particularly limited, it is preferably 180 ° C or lower, more preferably 160 ° C or lower, and more preferably 150 ° C or lower in consideration of moldability and the like. More preferred. The glass transition temperature of the polyamide (A) can be determined as a temperature at an inflection point that appears when the temperature is raised at a rate of 20 ° C./min using a differential scanning calorimeter (DSC). It can be determined by the method described in the example.

(Production method of polyamide (A))
The polyamide (A) can be produced by using any method known as a method for producing a crystalline polyamide. For example, a melt polymerization method using a dicarboxylic acid and a diamine as raw materials, a solid phase polymerization method, It can be produced by a method such as an extrusion polymerization method. Among these, the method for producing the polyamide (A) is preferably a solid-phase polymerization method from the viewpoint that thermal degradation during polymerization can be more favorably suppressed.
In order to set the molar ratio between the branched aliphatic diamine unit and the linear aliphatic diamine unit to the above-mentioned specific numerical range, the branched aliphatic diamine and the linear aliphatic diamine used as the raw materials are preferably used. The molar ratio of the above units may be used.
When, for example, 2-methyl-1,8-octanediamine and 1,9-nonanediamine are used as the branched aliphatic diamine and the linear aliphatic diamine, respectively, these can be produced by a known method. Known methods include, for example, a method of distilling a crude diamine reaction solution obtained by performing a reductive amination reaction using dialdehyde as a starting material. Further, 2-methyl-1,8-octanediamine and 1,9-nonanediamine can be obtained by fractionating the diamine crude reaction solution.

  For example, the polyamide (A) is prepared by adding a diamine, a dicarboxylic acid, and, if necessary, a catalyst and an endcapping agent at a time to produce a nylon salt, and then heat-polymerizing at a temperature of 200 to 250 ° C. It can be produced by prepolymerization and then solid phase polymerization or polymerization using a melt extruder. When the final stage of the polymerization is carried out by solid-phase polymerization, it is preferably carried out under reduced pressure or under an inert gas flow.If the polymerization temperature is in the range of 200 to 280 ° C., the polymerization rate is large and the productivity is excellent. Coloring and gelation can be effectively suppressed. The polymerization temperature in the case where the final stage of the polymerization is carried out by a melt extruder is preferably 370 ° C. or lower. When the polymerization is carried out under such conditions, a polyamide which hardly decomposes and has little deterioration is obtained.

Examples of the catalyst that can be used when producing the polyamide (A) include phosphoric acid, phosphorous acid, hypophosphorous acid, and salts or esters thereof. Examples of the above salts or esters include, for example, phosphoric acid, phosphorous acid or hypophosphorous acid, and potassium, sodium, magnesium, vanadium, calcium, zinc, cobalt, manganese, tin, tungsten, germanium, titanium, antimony and the like. Salts with metals; phosphoric acid, ammonium salts of phosphorous or hypophosphorous acid; ethyl, isopropyl, butyl, hexyl, isodecyl, octadecyl esters of phosphoric, phosphorous or hypophosphorous acid , Decyl ester, stearyl ester, phenyl ester and the like.
The amount of the catalyst used is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and 1.0% by mass or less based on 100% by mass of the total mass of the raw materials. And more preferably 0.5% by mass or less. If the amount of the catalyst used is equal to or more than the above lower limit, polymerization proceeds favorably. When the content is equal to or less than the upper limit, impurities derived from the catalyst are less likely to be generated. For example, when a polyamide composition is formed into a film, problems due to the impurities can be prevented.

[Halogen flame retardant (B)]
The halogen-based flame retardant (B) contained in the polyamide composition of the present invention is not particularly limited, and a known compound as a flame retardant containing a halogen element can be used. Examples thereof include a brominated flame retardant (B1) and chlorine. And the like. Brominated flame retardants (B1) are preferred. These may be used alone or in combination of two or more.

(Brominated flame retardant (B1))
Examples of the brominated flame retardant include hexabromocyclododecane, decabromodiphenyl oxide, octabromodiphenyl oxide, tetrabromobisphenol A, bis (tribromophenoxy) ethane, bis (pentabromophenoxy) ethane, and tetrabromobisphenol A epoxy Resin, tetrabromobisphenol A carbonate, ethylene (bistetrabromophthal) imide, ethylenebispentabromodiphenyl, tris (tribromophenoxy) triazine, bis (dibromopropyl) tetrabromobisphenol A, bis (dibromopropyl) tetrabromobisphenol S , Brominated polyphenylene ether (including poly (di) bromophenylene ether, etc.), brominated polystyrene (polydibromostyrene, Bromostyrene, cross-linked brominated polystyrene, etc. Modified brominated polystyrene to which epoxy acrylate or the like may be added), brominated cross-linked aromatic polymer, brominated epoxy resin, brominated phenoxy resin, brominated styrene- Examples thereof include a maleic anhydride polymer, tetrabromobisphenol S, tris (tribromoneopentyl) phosphate, polybromotrimethylphenylindane, and tris (dibromopropyl) -isocyanurate.

  As the brominated flame retardant (B1), bromination is used from the viewpoint of reducing the amount of corrosive gas generated during melt processing such as extrusion and molding, and improving the flame retardancy and mechanical properties of electric or electronic components. Polyphenylene ether and brominated polystyrene are preferred, and brominated polystyrene is more preferred.

  Brominated polystyrene is produced, for example, by polymerizing a styrene monomer to produce polystyrene and then brominating the benzene ring of the polystyrene, or by using a brominated styrene monomer (bromostyrene, dibromostyrene, tribromostyrene, etc.). It can be produced by a polymerization method.

  The bromine content in the brominated polystyrene is preferably from 55 to 75% by mass. By setting the bromine content to 55% by mass or more, the bromine amount required for flame retardation can be satisfied with a small brominated polystyrene content, and a decrease in the mechanical properties of the polyamide (A) is suppressed, A polyamide composition having excellent mechanical properties and heat resistance can be obtained. Further, by setting the bromine content to 75% by mass or less, a polyamide composition which does not easily undergo thermal decomposition during melt processing such as extrusion or molding, can suppress gas generation and the like, and is excellent in heat discoloration resistance is obtained. be able to.

(Chlorine flame retardant (B2))
Examples of the chlorinated flame retardant include chlorinated paraffin, chlorinated polyethylene, dodecachloropentacyclooctadeca-7,15-diene (“Dechlorane Plus 25” manufactured by Oxydental Chemical Co., Ltd.), and hetic anhydride.

(Halogen flame retardant content, etc.)
The polyamide composition of the present invention preferably contains the above-mentioned halogen-based flame retardant (B) in an amount of 5 to 100 parts by mass, preferably 10 to 75 parts by mass, based on 100 parts by mass of the polyamide (A). Parts by weight or less, more preferably 30 parts by weight or more and 70 parts by weight or less. By setting the content of the halogen-based flame retardant (B) to 5 parts by mass or more, a polyamide composition having excellent flame retardancy can be obtained. Further, by setting the content of the halogen-based flame retardant (B) to 100 parts by mass or less, generation of a decomposition gas at the time of melt-kneading, a decrease in fluidity (particularly, thin-wall fluidity) at the time of molding, and a molding die Adhesion of contaminants to the surface can be suppressed, and furthermore, deterioration of mechanical properties and appearance of a molded article can be suppressed. When a plurality of types of halogen-based flame retardants (B) are used, their total amount may be within the above range.

  According to the study of the present inventors, regarding the polyamide constituting the polyamide composition, when more than 40 mol% of the dicarboxylic acid units constituting the polyamide are naphthalenedicarboxylic acid units, 40 mol of the dicarboxylic acid units constituting the polyamide are used. It has been found that the combination of a halogen-based flame retardant and a polyamide tends to further improve the flame retardancy as compared with the case where more than% is terephthalic acid units. It has also been found that this tendency appears regardless of the ratio of the linear aliphatic diamine unit to the branched aliphatic diamine unit in the diamine unit constituting the polyamide. Therefore, for example, assuming an application in which only the importance of specific physical properties of the semi-aromatic polyamide is required, the ratio of the branched aliphatic diamine units in the diamine unit is the ratio of the linear aliphatic diamine units. When a polyamide composition is produced using a larger polyamide and a halogen-based flame retardant, there is a possibility that a polyamide composition having both the above-mentioned specific physical properties and flame retardancy can be obtained.

[Filler (C)]
The polyamide composition of the present invention may contain a filler (C). By using the filler (C), it is possible to obtain a polyamide composition excellent in flame retardancy, heat resistance, moldability, and mechanical strength in a thin wall.

  As the filler (C), those having various forms such as fibrous, flat, acicular, powder, and cloth can be used. Specifically, inorganic or organic fibrous fillers such as glass fiber, carbon fiber, wholly aromatic polyamide fiber (aramid fiber), liquid crystal polymer (LCP) fiber, gypsum fiber, brass fiber, ceramic fiber, and boron whisker fiber. (C1); flat fillers such as glass flakes, mica, and talc; needle-like fillers such as potassium titanate whiskers, aluminum borate whiskers, calcium carbonate whiskers, magnesium sulfate whiskers, wollastonite, sepiolite, zonotolite, and zinc oxide whiskers Filler (C2): silica, silica alumina, alumina, barium carbonate, magnesium carbonate, aluminum nitride, boron nitride, potassium titanate, titanium oxide, magnesium hydroxide, aluminum silicate (kaolin, clay, pyrophyllite, bentonite) , Kay Calcium, magnesium silicate (atapulgite), aluminum borate, calcium sulfate, barium sulfate, magnesium sulfate, asbestos, glass beads, carbon black, graphene, graphite, carbon nanotubes, silicon carbide, sericite, hydrotalcite, montmorillonite, Powdery fillers such as molybdenum sulfide, ultrahigh molecular weight polyethylene particles, phenolic resin particles, crosslinked styrene resin particles, crosslinked acrylic resin particles; and cloth-like fillers such as glass cloth. These may be used alone or in combination of two or more.

  The surface of the filler (C) is a polymer compound such as a silane coupling agent, a titanium coupling agent, an acrylic resin, a urethane resin, an epoxy resin, for the purpose of enhancing dispersibility and adhesion in the polyamide (A). Alternatively, it may be surface-treated with another low molecular compound.

Among the fillers (C), at least one selected from the group consisting of fibrous fillers (C1) and needle-like fillers (C2), since a molded article having a low cost and high mechanical strength can be obtained. Is preferred. From the viewpoint of high strength and low cost, the fibrous filler (C1) is preferable, and glass fiber is more preferable. From the viewpoint of obtaining a molded product having high surface smoothness, the needle-like filler (C2) is preferable.
As the fibrous filler (C1) and the acicular filler (C2), at least one selected from the group consisting of glass fibers, wollastonite, potassium titanate whiskers, calcium carbonate whiskers, and aluminum borate whiskers is preferable. , Glass fibers and wollastonite are more preferred, and glass fibers are even more preferred.

The average fiber length of the fibrous filler (C1) is preferably 1 to 10 mm, more preferably 1 to 7 mm, and further preferably 2 to 4 mm. The average fiber diameter of the fibrous filler (C1) is preferably from 6 to 20 μm, more preferably from 6 to 15 μm, from the viewpoint of obtaining mechanical strength.
The average fiber length and average fiber diameter of the fibrous filler (C1) were determined by measuring the fiber length and fiber diameter of 400 fibrous fillers (C1) arbitrarily selected by image analysis using an electron microscope. , By calculating the respective mass average values.
The average fiber length and the average fiber diameter of the fibrous filler (C1) in the polyamide composition or the molded product obtained by molding the polyamide composition are determined, for example, in an organic solvent. Is dissolved, the fibrous filler (C1) is extracted, and it can be determined by image analysis using an electron microscope in the same manner as described above.

  Examples of the cross-sectional shape of the fibrous filler (C1) and the needle-like filler (C2) include a rectangular shape, an oblong shape close to a rectangle, an elliptical shape, a cocoon shape, a cocoon shape with a narrowed central portion in the longitudinal direction, and the like. . Among them, the cross-sectional shape of the fibrous filler (C1) and the needle-like filler (C2) is preferably rectangular, oval, nearly rectangular, elliptical, or cocoon-shaped.

When the fibrous filler (C1) is a glass fiber, specific compositions include an E glass composition, a C glass composition, an S glass composition, and an alkali glass composition. The tensile strength of the glass fiber is arbitrary, but is usually 290 kg / mm ² or more. Among them, E glass is preferable from the viewpoint of easy availability. These glass fibers are preferably surface-treated with a silane coupling agent such as γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and the like. The adhesion amount is usually 0.01% by mass or more based on the mass of the glass fiber (the total amount of the glass fiber and the surface treatment agent).

  The content of the filler (C) is preferably from 0.1 part by mass to 200 parts by mass, more preferably from 1 part by mass to 180 parts by mass, based on 100 parts by mass of the polyamide (A). More preferably, it is 5 parts by mass or more and 150 parts by mass or less. By setting the content of the filler (C) to 0.1 part by mass or more with respect to 100 parts by mass of the polyamide (A), the toughness, mechanical strength, and the like of the polyamide composition of the present invention are improved. By setting the amount to 200 parts by mass or less, a polyamide composition having excellent moldability can be obtained.

[Flame retardant (D)]
The polyamide composition of the present invention may contain a flame retardant aid (D). By using the flame retardant aid (D) in combination with the halogen-based flame retardant (B), the polyamide composition of the present invention and a molded article comprising the same can exhibit more excellent flame retardancy.

  Examples of the flame retardant aid (D) include antimony oxides such as diantimony trioxide, diantimony tetroxide and diantimony pentoxide, and antimony compounds such as antimonates such as sodium antimonate; melamine orthophosphate, pyrophosphoric acid Melamine compounds such as melamine, melamine borate and melamine polyphosphate; tin oxides such as tin monoxide and tin dioxide; iron oxides such as ferric oxide and gamma iron oxide; aluminum oxide, silicon oxide (silica), and titanium oxide Metal oxides such as zirconium oxide, manganese oxide, manganese oxide, molybdenum oxide, cobalt oxide, bismuth oxide, chromium oxide, tin oxide, nickel oxide, copper oxide and tungsten oxide; metal hydroxides such as aluminum hydroxide; aluminum, iron, Titanium, manganese, zinc, molybdenum, cobalt, bismuth, chromium Metal powders such as tin, antimony, nickel, copper, and tungsten; metal carbonates such as zinc carbonate, calcium carbonate, magnesium carbonate, and barium carbonate; metal borates such as zinc borate, calcium borate, and aluminum borate; Zinc stannate such as tin zinc oxide; silicone; These may be used alone or in combination of two or more.

  Among the above, at least one selected from the group consisting of antimony compounds, melamine compounds, metal oxides, metal hydroxides, metal borates, and zinc stannate is preferable. At least one selected from the group consisting of antimony, diantimony pentoxide, sodium antimonate, melamine orthophosphate, melamine pyrophosphate, melamine borate, melamine polyphosphate, aluminum oxide, aluminum hydroxide, zinc borate, and zinc stannate Species are more preferred.

  The flame retardant aid (D) is preferably contained in the polyamide composition of the present invention as a powder. The upper limit of the average particle size is preferably 30 μm, more preferably 15 μm, further preferably 10 μm, and most preferably 7 μm. On the other hand, the lower limit of the average particle size of the flame retardant aid (D) is preferably 0.01 μm. When the average particle size is 0.01 to 30 µm, the obtained polyamide composition has improved flame retardancy.

  When the flame retardant aid (D) is contained, its content is preferably from 1 part by mass to 30 parts by mass, more preferably from 1 part by mass to 25 parts by mass, based on 100 parts by mass of the polyamide (A). And 3 to 20 parts by mass is more preferable.

[Other additives]
The polyamide composition requires other additives in addition to the above-mentioned polyamide (A), halogen-based flame retardant (B), and filler (C) and flame retardant auxiliary (D) used as needed. May be included accordingly.

  Other additives include, for example, organic heat stabilizers such as phenol heat stabilizers, phosphorus heat stabilizers, sulfur heat stabilizers, amine heat stabilizers, etc .; heat stabilizers such as copper compounds; coloring agents UV absorber; light stabilizer; antistatic agent; crystal nucleating agent; plasticizer; lubricant; lubricant; dispersant; oxygen absorber; hydrogen sulfide adsorbent; Modifiers; drip inhibitors such as fluororesins;

  The content of the other additives is not particularly limited as long as the effects of the present invention are not impaired, but is preferably 0.02 to 200 parts by mass, and more preferably 0.03 to 100 parts by mass with respect to 100 parts by mass of the polyamide (A). Parts by mass are more preferred.

[Method for producing polyamide composition]
There is no particular limitation on the method for producing the polyamide composition, and the polyamide (A), the halogen-based flame retardant (B), and the filler (C), the flame-retardant auxiliary (D), and other additives used as needed. A method capable of uniformly mixing agents and the like can be preferably employed. In general, a method of melt-kneading using a single-screw extruder, a twin-screw extruder, a kneader, a Banbury mixer or the like is preferably employed for mixing. The melt-kneading conditions are not particularly limited, and for example, a method of melt-kneading in a temperature range higher by about 10 to 50 ° C. than the melting point of the polyamide (A) for about 1 to 30 minutes is exemplified.

<Molded product>
(Molding method)
A molded article comprising the polyamide composition of the present invention, using the polyamide composition of the present invention, injection molding, blow molding, extrusion molding, compression molding, stretch molding, vacuum molding, foam molding, It can be obtained by molding by various molding methods such as a rotational molding method, an impregnation method, a laser sintering method, and a hot melt lamination method. Furthermore, the polyamide composition of the present invention and another polymer or the like can be composite-molded to obtain a molded article.

(Application)
Examples of the molded article include films, sheets, tubes, pipes, gears, cams, various housings, rollers, impellers, bearing retainers, spring holders, clutch parts, chain tensioners, tanks, wheels, connectors, switches, sensors, and sockets. , Capacitors, hard disk components, jacks, fuse holders, relays, coil bobbins, resistors, IC housings, LED reflectors, and the like.
In particular, the polyamide composition of the present invention is required to have high-temperature properties, chemical resistance, and flame retardancy, injection molded members, heat-resistant films, tubes for transporting various chemicals / chemicals, intake pipes, blow-by tubes, base materials for 3D printers, and the like. It is also suitable for molded products for automobiles requiring high heat resistance and chemical resistance, for example, interior and exterior parts of automobiles, parts in engine room, cooling system parts, sliding parts, electrical parts, etc. Can be used for In addition, the polyamide composition of the present invention can be used as an electrical component, an electronic component, or a molded product requiring heat resistance corresponding to a surface mounting process. Such molded products include surface-mounted connectors, sockets, camera modules, power supply components, switches, sensors, capacitor seat plates, hard disk components, relays, resistors, fuse holders, coil bobbins, surface mount components such as IC housings, etc. Can be suitably used.

  Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Each evaluation in Production Examples, Examples, and Comparative Examples was performed according to the following methods.
-Intrinsic Viscosity The intrinsic viscosity (dl / g) at a concentration of 0.2 g / dl and a temperature of 30 ° C was determined for the polyamide (sample) obtained in the Production Example using concentrated sulfuric acid as a solvent from the following relational expression.
η _inh = [ln (t ₁ / t ₀ )] / c
In the above relational expression, η _inh represents an intrinsic viscosity (dl / g), t ₀ represents a flow time (second) of a solvent (concentrated sulfuric acid), t ₁ represents a flow time (second) of a sample solution, c Represents the concentration (g / dl) of the sample in the sample solution (ie, 0.2 g / dl).

-Melting point and glass transition temperature The melting point and glass transition temperature of the polyamide obtained in the production example were measured using a differential scanning calorimeter "DSC7020" manufactured by Hitachi High-Tech Science Corporation.
The melting point was measured based on ISO11357-3 (2011 2nd edition). Specifically, the sample (polyamide) is heated at a rate of 10 ° C./min from 30 ° C. to 340 ° C. in a nitrogen atmosphere, and is kept at 340 ° C. for 5 minutes to completely melt the sample. / Minute and cooled to 50 ° C. and kept at 50 ° C. for 5 minutes. The peak temperature of the melting peak that appears when the temperature is raised again to 340 ° C. at a rate of 10 ° C./min is defined as the melting point (° C.). did.
The glass transition temperature (° C.) was measured according to ISO11357-2 (2013, 2nd edition). Specifically, under a nitrogen atmosphere, the sample (polyamide) is heated from 30 ° C. to 340 ° C. at a rate of 20 ° C./min, and kept at 340 ° C. for 5 minutes to completely melt the sample. / Minute and cooled to 50 ° C. and kept at 50 ° C. for 5 minutes. The temperature at the inflection point that appeared when the temperature was raised again to 200 ° C. at a rate of 20 ° C./min was taken as the glass transition temperature (° C.).

-Flame retardancy The flame retardancy was evaluated according to the UL-94 standard.
Using an injection molding machine (clamping force: 80 tons, screw diameter: φ26 mm) manufactured by Nissei Plastic Industry Co., Ltd., using the polyamide composition obtained in each of Examples and Comparative Examples, the melting point of the polyamide was set to 20 or more. -30 ° C higher cylinder temperature, the polyamide compositions of Example 1 and Comparative Example 1 were subjected to a mold temperature of 160 ° C, and the polyamide compositions of Comparative Examples 2 and 3 were subjected to a mold temperature of 140 ° C. The polyamide composition was molded using a T-runner mold to obtain a test piece having a thickness of 0.75 mm, a width of 13 mm, and a length of 125 mm.
Next, the upper end of the obtained test piece was clamped to fix the test piece vertically, and a blue flame having a height of 20 ± 1 mm was applied to the lower end for 10 seconds and released, and the burning time of the test piece (first time) Was measured. Immediately after the fire was extinguished, the flame was again applied to the lower end and released, and the burning time (second time) of the test piece was measured. The same measurement was repeated for five pieces to obtain a total of ten data, five data of the first burning time and five data of the second burning time. The total of the ten data was T, and the maximum value of the ten data was M, and evaluation was performed according to the following evaluation criteria.
The presence or absence of drip during flame contact was visually confirmed.
〔Evaluation criteria〕
V-0: T was not more than 50 seconds and M was not more than 10 seconds, and it did not burn up to the clamp, and did not ignite cotton 12 inches below even if the flamed melt fell.
V-1: T was not longer than 250 seconds and M was not longer than 30 seconds, the flame did not burn up to the clamp, and even if the flaming melt dropped, the cotton 12 inches below did not ignite.
V-2: T was 250 seconds or less and M was 30 seconds or less, the flame did not burn up, the melted flame dropped and ignited cotton 12 inches below.
X: When none of the evaluation criteria of UL94 is satisfied.

-Blister resistance Using an injection molding machine manufactured by Sumitomo Heavy Industries, Ltd. (mold clamping force: 18 tons, screw diameter: φ18 mm), using the polyamide compositions obtained in Examples and Comparative Examples, polyamide The polyamide compositions of Example 1 and Comparative Example 1 were set at a mold temperature of 160 ° C, and the polyamide compositions of Comparative Examples 2 and 3 were set at a mold temperature of 140 ° C. The polyamide composition was molded (injection molded) using a T-runner mold under the conditions described in (1) to prepare test pieces (sheets) having a length of 30 mm, a width of 10 mm, and a thickness of 1 mm.
The obtained test piece was allowed to stand for 168 hours at a temperature of 85 ° C. and a relative humidity of 85%. Thereafter, a reflow test was performed on the test piece using an infrared heating furnace (SMT scope, manufactured by Sanyo Seiko Co., Ltd.). In the reflow test, the temperature was raised from 25 ° C to 150 ° C over 60 seconds, then raised to 180 ° C over 90 seconds, and then raised to the peak temperature over 60 seconds and held at the peak temperature for 20 seconds. did. The reflow test was performed by changing the peak temperature from 250 ° C. to 270 ° C. in steps of 10 ° C. After the completion of the reflow test, the appearance of the test piece was visually observed. The limit temperature at which the test piece does not melt and blisters are not generated is defined as the blister-resistant temperature. When the blister-resistant temperature exceeds 260 ° C, “℃”; when the blister-resistant temperature is 250 ° C or more and 260 ° C or less. Is “△”, and the case where the blister resistance is less than 250 ° C. is “X”, which was used as an index of blister resistance. “○” and “△” are practically acceptable levels.

<< Preparation of test piece >>
Using an injection molding machine (mold clamping force: 100 tons, screw diameter: φ32 mm) manufactured by Sumitomo Heavy Industries, Ltd., using the polyamide compositions obtained in Examples and Comparative Examples, With the cylinder temperature being 20 to 30 ° C. higher, the polyamide compositions of Example 1 and Comparative Example 1 were subjected to a mold temperature of 160 ° C., and the polyamide compositions of Comparative Examples 2 and 3 were subjected to a mold temperature of 140 ° C. A multi-purpose test piece type A1 (a dumbbell-shaped test piece described in JIS K7139; 4 mm thick, total length 170 mm, parallel portion length 80 mm, parallel portion width 10 mm) is molded from a polyamide composition using a T-runner mold. Produced.

-Tensile breaking strength Using an autograph (manufactured by Shimadzu Corporation) according to ISO527-1 (2012 second edition), using the multipurpose test piece type A1 (4 mm thick) produced by the above method. The tensile strength at break (MPa) at 23 ° C. was measured.

-Thermal deformation temperature A test piece (4 mm thick, total length 80 mm, width 10 mm) was prepared by cutting from the multipurpose test piece type A1 (4 mm thick) prepared by the above method, and an HDT tester manufactured by Toyo Seiki Seisaku-sho, Ltd. Using S-3M, the heat distortion temperature (° C.) was measured in accordance with ISO 75 (2013, 3rd edition).

-Water absorption The multipurpose test piece type A1 (4 mm thick) produced by the above method was weighed. Then, after immersion in water and immersion treatment at 23 ° C. for 168 hours, the weight increase was determined by weighing again, and this was divided by the weight before immersion to determine the water absorption (%).

  The components used for preparing the polyamide compositions in Examples and Comparative Examples are shown.

"polyamide"
[Production Example 1]
Production of semiaromatic polyamide (PA9N-1) 9110.2 g (42.14 mol) of 2,6-naphthalenedicarboxylic acid, a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine [former / The latter = 4/96 (molar ratio)] 6833.7 g (43.30 mol), 210.0 g (1.72 mol) of benzoic acid, 16.2 g of sodium hypophosphite monohydrate (based on the total mass of the raw materials) 0.1% by mass) and 8.3 liters of distilled water were placed in an autoclave having an internal volume of 40 liters, followed by purging with nitrogen. The mixture was stirred at 100 ° C for 30 minutes, and the temperature inside the autoclave was raised to 220 ° C over 2 hours. At this time, the pressure inside the autoclave was increased to 2 MPa. Heating was continued for 5 hours while maintaining the pressure at 2 MPa, and steam was gradually removed to cause a reaction. Next, the pressure was reduced to 1.3 MPa over 30 minutes, and the reaction was further performed for 1 hour to obtain a prepolymer. The obtained prepolymer was dried at 100 ° C. under reduced pressure for 12 hours and pulverized to a particle size of 2 mm or less. This was subjected to solid-phase polymerization at 230 ° C. and 13 Pa (0.1 mmHg) for 10 hours to obtain a polyamide. This polyamide is abbreviated as "PA9N-1".

[Production Example 2]
Production of semi-aromatic polyamide (PA9T-1) 8190.7 g (49.30 mol) of terephthalic acid, a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine [the former / the latter = 85/15] (Molar ratio)] 7969.4 g (50.35 mol), benzoic acid 171.0 g (1.40 mol), sodium hypophosphite monohydrate 16.3 g (0.1 wt. % By mass) and 5.5 liters of distilled water were placed in an autoclave having an internal volume of 40 liters. Thereafter, a polyamide was obtained in the same manner as in Production Example 1. This polyamide is abbreviated as "PA9T-1".

《Halogen flame retardant》
Glycidyl methacrylate-modified polybrominated styrene (“Firemaster CP-44HF” manufactured by Chemtura, bromine content 64%)
"filler"
Glass fiber ("CS-3G 225S" manufactured by Nitto Boseki Co., Ltd.)
《Flame retardant aid》
Tin zinc oxide ("Flamard S" manufactured by William Blythe)
《Other additives》
・ Heat stabilizer Phenolic heat stabilizer (“SUMILIZER GA-80” manufactured by Sumitomo Chemical Co., Ltd.)
・ Lubricant Low molecular weight polyolefin lubricant (“HiWAX 200P” manufactured by Mitsui Chemicals, Inc.)
・ Crystal nucleating agent talc (“TALC # 5000S” manufactured by Fuji Talc Industries, Ltd.)
・ Drip prevention agent Fluororesin powder (“Teflon 640J” manufactured by Mitsui-Kemers Fluoro Products)

[Example 1 and Comparative Examples 1 to 3]
The components other than the filler are mixed in advance in the proportions shown in Table 1, and fed from an upstream hopper of a twin-screw extruder (“BTN-32” manufactured by Plastics Engineering Laboratory Co., Ltd.), and at the downstream of the extruder. The filler was fed from the side feed port at a ratio shown in Table 1. The mixture was melt-kneaded at a cylinder temperature 20 to 30 ° C. higher than the melting point of the polyamide, extruded, cooled and cut to produce a pellet-shaped polyamide composition.

The above-mentioned various physical properties were evaluated using the polyamide compositions obtained in the above Examples and Comparative Examples. Table 1 shows the results.
In Table 1, C9DA indicates 1,9-nonanediamine unit, and MC8DA indicates 2-methyl-1,8-octanediamine unit.

Table 1 shows that the polyamide composition of Example 1 is excellent in flame retardancy and has a level of blister resistance suitable for practical use as compared with Comparative Examples 1 to 3.
The polyamide composition of Example 1 is superior to Comparative Examples 1 to 3 in the evaluation of tensile strength at break, heat distortion temperature, and water absorption, and is equal to or better than that of the polyamide composition of the present invention. It can be seen that they are also excellent in heat resistance and low water absorption.
As described in Patent Document 1, it is known that the use of an aliphatic diamine having a side chain reduces the crystallinity of the obtained polyamide, and is not preferable in terms of heat resistance, chemical resistance, and the like. . On the other hand, the polyamide composition of the present invention is characterized in that the polyamide (A) contained therein has a dicarboxylic acid unit mainly composed of a naphthalenedicarboxylic acid unit and a diamine unit mainly composed of a branched aliphatic diamine unit. By having the above structure, chemical resistance is further improved, and in addition, various physical properties such as mechanical properties, heat resistance, and low water absorption are more excellent.

Claims (20)

A polyamide (A) having a dicarboxylic acid unit and a diamine unit, and a halogen-based flame retardant (B),
Naphthalenedicarboxylic acid units account for more than 40 mol% and 100 mol% or less of the dicarboxylic acid units,
60 mol% or more and 100 mol% or less of the diamine unit are a branched aliphatic diamine unit and a linear aliphatic diamine unit of an optional constitutional unit, and the branched aliphatic diamine unit and the linear aliphatic diamine A polyamide composition, wherein the proportion of the branched aliphatic diamine unit to the total 100 mol% of the units is 60 mol% or more.   The ratio of the said branched aliphatic diamine unit with respect to 100 mol% of the total of the said branched aliphatic diamine unit and the said linear aliphatic diamine unit is 60 mol% or more and 99 mol% or less. Polyamide composition.   The ratio of the said branched aliphatic diamine unit with respect to 100 mol% in total of the said branched aliphatic diamine unit and the said linear aliphatic diamine unit is 80 mol% or more and 99 mol% or less. Polyamide composition.   The polyamide composition according to any one of claims 1 to 3, wherein the branched aliphatic diamine unit has 4 to 18 carbon atoms.   The said branched aliphatic diamine unit is a structural unit derived from the diamine which has at least 1 type chosen from the group which consists of a methyl group and an ethyl group as a branched chain, The Claims any one of Claims 1-4. Polyamide composition.   The branched aliphatic diamine unit is derived from a diamine having a branched chain in at least one of the carbon atom at the 2-position and the carbon atom at the 3-position when the carbon atom to which any one of the amino groups is bonded is placed at the 1-position. The polyamide composition according to any one of claims 1 to 5, which is a constituent unit.   The branched aliphatic diamine units are 2-methyl-1,5-pentanediamine, 3-methyl-1,5-pentanediamine, 2-methyl-1,8-octanediamine, and 2-methyl-1,9 The polyamide composition according to any one of claims 1 to 3, which is a structural unit derived from at least one type of diamine selected from the group consisting of -nonanediamine.   The polyamide composition according to any one of claims 1 to 7, wherein the linear aliphatic diamine unit has 4 to 18 carbon atoms.   The linear aliphatic diamine unit is 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonanediamine The structural unit according to any one of claims 1 to 7, wherein the structural unit is derived from at least one diamine selected from the group consisting of, 1,10-decanediamine, 1,11-undecanediamine, and 1,12-dodecanediamine. Item 6. The polyamide composition according to Item.   The polyamide composition according to any one of claims 1 to 9, wherein the halogen-based flame retardant (B) is contained in an amount of 5 parts by mass or more and 100 parts by mass or less based on 100 parts by mass of the polyamide (A).   The polyamide composition according to any one of claims 1 to 10, wherein the halogen-based flame retardant (B) is a brominated flame retardant (B1).   The polyamide composition according to claim 11, wherein the brominated flame retardant (B1) is a brominated polystyrene.   The polyamide composition according to any one of claims 1 to 12, further comprising a filler (C).   The polyamide composition according to claim 13, wherein the filler (C) is contained in an amount of 0.1 to 200 parts by mass with respect to 100 parts by mass of the polyamide (A).   The polyamide composition according to any one of claims 1 to 14, further comprising a flame retardant aid (D).   The polyamide composition according to claim 15, wherein the flame retardant aid (D) is contained in an amount of 1 part by mass or more and 30 parts by mass or less based on 100 parts by mass of the polyamide (A).   The flame retardant aid (D) is diantimony trioxide, diantimony tetroxide, diantimony pentoxide, sodium antimonate, melamine orthophosphate, melamine pyrophosphate, melamine borate, melamine polyphosphate, aluminum oxide, hydroxide The polyamide composition according to claim 15 or 16, wherein the polyamide composition is at least one selected from the group consisting of aluminum, zinc borate, and zinc stannate.   A molded article comprising the polyamide composition according to any one of claims 1 to 17.   The molded article according to claim 18, which is an electric part or an electronic part.   The molded article according to claim 18 or 19, which is a surface mount component.