JPH0627247B2 - Flame-retardant polyester composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to a flame-retardant polyester composition having excellent flame retardancy, mechanical properties, molding retention stability, molding fluidity and heat resistance.

<Prior Art> Aromatic polyesters typified by polyethylene terephthalate, polybutylene terephthalate and the like are being widely used for machine mechanism parts, electric parts, automobile parts and the like by utilizing their excellent characteristics. On the other hand, these industrial materials are strongly required to have flame safety, that is, flame retardancy, in addition to the balance of general chemical and physical properties. Further, in the field of electronic connectors and the like, it is necessary that the flame retardant does not bleed out while it has good mechanical properties even when flame retardancy is imparted. Brominated polycarbonate oligomers and brominated epoxy oligomers have been variously studied as flame retardants to meet such demands.

However, since the brominated polycarbonate oligomer is a carbonic acid ester, it causes an ester exchange reaction between aromatic polyesters having ester bonds as well, and reduces the mechanical properties of the aromatic polyesters. There were problems such as poor stability of molding retention and easy bleed-out during heat treatment of molded products.

Further, brominated epoxy oligomers also have problems such as thickening during molding retention, poor fluidity, and low impact resistance.

Therefore, a composition using a brominated phenoxy resin having an average degree of polymerization of 11 or more is disclosed in JP-A-58-11849.

A composition obtained by combining a thermoplastic polyester with a halogenated epoxy resin having an average degree of polymerization of 10 or less, a halogen-containing copolymer, an inorganic flame-retardant aid, and an impact resistance improver containing 50% by weight or more of an acrylate rubber component. JP 59-2
It is disclosed in Japanese Patent No. 0353. In this publication, the polymerization degree ratio between the brominated phenoxy resin (average degree of polymerization 15) and the brominated epoxy resin (average degree of polymerization 4) is 3.75 / 1, and the two resins, antimony trioxide and acrylic graftmer are used. A composition in which is blended with polybutylene terephthalate is disclosed in the examples.

<Problems to be Solved by the Invention> However, when a composition having an average polymerization degree of 11 or more and less than 20 is used as the brominated phenoxy resin in the composition described in JP-A-58-18849, impact resistance and In terms of heat resistance, it is still unsatisfactory, and when a polymer having an average degree of polymerization of 20 or more is used, there are problems such as poor molding fluidity and deterioration of retention stability.

Further, in the composition of JP-A-59-20353, a brominated phenoxy resin having a degree of polymerization of 11 or more and less than 20,
When two resins having a polymerization degree of 10 or less and a polymerization degree ratio of 4/1 or less are used in combination with antimony trioxide or an acrylate rubber, the impact resistance is slightly improved, but it is difficult. It has been found that there is a problem that the flammability, heat resistance and stagnant stability are reduced.

Therefore, as a result of intensive studies to solve the above problems, the present inventors have found that a specific polymerization of an aromatic polyester with an antimony compound, a brominated phenoxy resin having a polymerization degree of 20 or more and a brominated epoxy compound having a polymerization degree of 10 or less. Flame retardancy and
The inventors have found that an aromatic polyester composition having excellent mechanical properties such as impact resistance, molding retention stability, molding fluidity and heat resistance can be obtained, and reached the present invention.

<Means for Solving the Invention> That is, the present invention relates to (A) an aromatic polyester (B) a brominated phenoxy resin having a skeleton represented by the following general formula (I). (Alkylene group for X C ₁ ~ ₁₀ in the above formula (I), an alkylidene group, a carbonyl group, -O -, - S- or -S
O ₂ −, n represents an integer of 20 or more. ) (C) A low molecular weight brominated epoxy compound represented by the following general formula (II) and (In the formula, X is the same as the substituent of the formula (I), p and q each represent an integer of 1 to 4, and n ′ represents an integer of 0 to 10.) (D) Composition comprising antimony compound The total amount of the component (B) and the component (C) is 2 to 50 parts by weight, and the component is 100 parts by weight of the component (A).
The weight ratio (B) / (C) of (B) and component (C) is 95/5 to 50/50.
And the component (D) is 1 to 50 parts by weight, and the ratio [n / (n '+ 1)] of the polymerization degrees of the component (B) and the component (C) is 4
The flame-retardant polyester composition is 5/1 to 30/1.

The (A) aromatic polyester used in the present invention is a polyester having an aromatic ring as a chain unit of a polymer and comprises an aromatic dicarboxylic acid (or its ester-forming derivative) and a diol (or its ester-forming derivative). It is a polymer or copolymer obtained by a condensation reaction containing the main component.

The aromatic dicarboxylic acid referred to here is terephthalic acid,
Isophthalic acid, orthophthalic acid, 1,5-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6
-Naphthalenedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 3,3'-biphenyldicarboxylic acid, 4,
4'-diphenyl ether dicarboxylic acid, 4,4'-diphenyl methane dicarboxylic acid, 4,4'-diphenyl sulfone dicarboxylic acid, 4,4'-diphenyl isopropylidene dicarboxylic acid, 1,2-bis (phenoxy) ) Ethane-4,4'-dicarboxylic acid, 2,5-anthracene dicarboxylic acid, 2,6-anthracene dicarboxylic acid, 4,
Examples thereof include 4'-p-terphenylenedicarboxylic acid and 2,5-pyridinedicarboxylic acid, and terephthalphthalic acid can be preferably used.

You may use these aromatic dicarboxylic acid in mixture of 2 or more types. If it is a small amount, it is possible to mix and use one or more adipic acid, azelaic acid, sebacic acid, aliphatic dicarboxylic acid such as dodecanedioic acid, and alicyclic dicarboxylic acid such as cyclohexanedicarboxylic acid together with these aromatic dicarboxylic acids. it can.

As the diol component, ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, neopentyl glycol, 2-methyl-
Aliphatic diols such as 1,3-propanediol, diethylene glycol and triethylene glycol, 1,4-
Preferred examples include alicyclic diols such as cyclohexanedimethanol, and mixtures thereof.
If it is a small amount, a long-chain diol having a molecular weight of 400 to 6,000, that is, polyethylene glycol, poly-1,3
-Propylene glycol, polytetramethylene glycol and the like may be copolymerized with one or more kinds.

Specific preferred aromatic polyesters include polyethylene terephthalate, polypropylene terephthalate,
Polybutylene terephthalate, polyhexylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene-1,2-bis (phenoxy)
In addition to ethane-4,4'-dicarboxylate and the like, copolymerized polyesters such as polyethylene isophthalate / terephthalate, polybutylene terephthalate / isophthalate, polybutylene terephthalate / decane dicarboxylate and the like can be mentioned. Of these, polybutylene terephthalate having a good balance of mechanical properties and moldability can be used particularly preferably.

The aromatic polyester used in the present invention preferably has a relative viscosity of 1.15 to 2.0, particularly 1.3 to 1.85, measured at 25 ° C. in a 0.5% o-chlorophenol solution.

The (B) brominated phenoxy resin used in the present invention is that represented by the above general formula (I), for example, in the presence of a suitable catalyst, if necessary using a solvent and brominated bisphenol glycidyl ether It is produced by a method of reacting brominated bisphenol.

Examples of the brominated bisphenol compound as a constituent of the brominated phenoxy resin of the general formula (I) include 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane and bis (3,5- Dibromo-4-hydroxyphenyl) methane, bis (3,5 dibromo-4-hydroxyphenyl) phenylmethane, 1,1-bis (3,5-dibromo-4-hydroxyphenyl) ethane, bis (3,5
-Dibromo-4-hydroxyphenyl) sulfone, bis (3,5-dibromo-4-hydroxyphenyl) ether, bis (3,5-dibromo-4-hydroxyphenyl) ketone, bis (3,5-dibromo) -4-Hydroxyphenyl) sulphide and the like can be mentioned. Among them, it is most preferable to use 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane, which is usually called tetrabromobisphenol A.

As the brominated phenoxy resin of the present invention, those having a glycidyl group and / or a hydroxyl group as a terminal group are generally used, and further, these terminal groups are blocked with carboxylic acids, phenols, amines or alcohols. Things can also be used.

The average degree of polymerization of the brominated phenoxy resin used in the present invention must be 20 or more, preferably 25.
-100, more preferably 30-70. When the average degree of polymerization is less than 20, the composition has low impact resistance and heat resistance, which is not preferable.

Next, the low molecular weight brominated epoxy compound (C) used in the present invention is represented by the general formula (II), and known methods such as brominated bisphenol and epichlorohydrin, or brominated bisphenol diglycidyl It can be obtained by condensing ether and brominated bisphenol by adjusting the polymerization conditions.

As the brominated bisphenol compound which is a constituent of the low molecular weight brominated epoxy compound (C) of the general formula (II), the same as those described in the section of (B) brominated phenoxy resin and 2,2 -Bis (3-bromo-4-hydroxyphenyl) propane, 2,2-bis (2,3,5,6)
-Tetrabromo-4-hydroxyphenyl) propane,
Bis (3-bromo-4-hydroxyphenyl) sulfone and the like, among them 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane and bis (3,3
5-dibromo-4-hydroxyphenyl) sulfone is preferred.

The low molecular weight brominated epoxy compound used in the present invention usually has a bromine content of preferably 30% by weight or more, more preferably 40% by weight or more.

Further, the average degree of polymerization of the low molecular weight brominated epoxy compound used in the present invention needs to be 10 or less, and preferably 2 to 8. When the average degree of polymerization exceeds 10, the effect of improving the molding retention stability and molding fluidity of the aromatic polyester is reduced, which is not preferable.

The total amount of (B) brominated phenoxy resin and (C) low molecular weight brominated epoxy compound used in the present invention is 2 to 50 parts by weight, preferably 3 to 40 parts by weight, based on 100 parts by weight of the aromatic polyester. It is preferably 5 to 30 parts by weight. If the amount added is less than 2 parts by weight, the flame retardance of the aromatic polyester is not sufficiently improved, while if it exceeds 50 parts by weight, the mechanical properties of the aromatic polyester tend to be impaired, which is not preferable.

Further, the weight ratio (B) / (C) of the component (B) and the component (C) is 95/5 to
50/50, preferably 90/10 to 60/40, more preferably 85/15 to 65/35, and the ratio of the degree of polymerization of component (B) and component (C) is 4.5 / 1 to 30. / 1,
Preferably 5/1 to 20/1, more preferably 6/1 to
It must be in the 15/1 range. Weight ratio (B) / (C) is 9
When it is more than 5/5, the molding fluidity and the retention stability are not improved, while when it is less than 50/50, the impact resistance and heat resistance are deteriorated, which is not preferable. Further, when the ratio of the degree of polymerization of the component (B) and the component (C) is less than 4.5 / 1, retention stability and mechanical properties during molding are deteriorated,
On the other hand, when it is more than 30/1, both heat resistance and impact resistance are deteriorated, which is not preferable.

In the present invention, the flame retardancy is synergistically improved by adding the antimony compound as a flame retardant auxiliary together with the above-mentioned brominated phenoxy resin which is a flame retardant and the low molecular weight brominated epoxy compound. Various kinds of antimony compounds can be used. Specifically, antimony trioxide, antimony oxide such as antimony pentoxide, antimony phosphate, sodium antimonate, KSb (OH) ₆ , potassium antimonyl tartrate, Sb (OCH ₂ CH ₃ ) ₃ , Sb (OCH (CH ₃ ) CH ₂ C
H ₃ ] ₃ , triphenylstibine and the like can be mentioned, and antimony oxide can be preferably used.

The addition amount of the antimony compound in the present invention is 1 to 50 parts by weight, preferably 3 to 30 parts by weight, relative to 100 parts by weight of the aromatic polyester. If it exceeds 50 parts by weight, the mechanical properties of the aromatic polyester will be impaired. It is more preferable to add 2 to 5 atoms of bromine in the added flame retardant at a ratio of 1 antimony atom in the antimony compound. At the same time, other flame retardant auxiliary agents such as boron oxide, zirconium oxide, iron oxide and barium sulfate may be used in combination.

Although not particularly essential, when a fibrous and / or granular filler is added to the composition of the present invention, the rigidity can be significantly improved without deteriorating other properties. Examples of such fillers include glass fiber, carbon fiber, metal fiber, aramid fiber, ceramic fiber, asbestos, potassium whisker titanate, wollastonite, gypsum fiber, sepiolite, glass beads, glass flakes,
Examples thereof include talc, mica, clay, calcium carbonate, barium sulfate, titanium oxide, and aluminum oxide, and among them, a glass fiber of a chopped strand type can be preferably used. The addition amount of these is usually 3 to 80 parts by weight with respect to 100 parts by weight of the aromatic polyester.

Further, the composition of the present invention is characterized in that the residence stability and the heat resistance can be improved by further adding a phosphorus compound.

Examples of such phosphorus compounds include phosphoric acid esters such as trimethyl phosphate and triphenyl phosphate, phosphite compounds such as triphenyl phosphite and triisodecyl phosphite, and phosphates such as sodium phosphate and lithium phosphate. . The addition amount of the phosphorus compound is 0.01 to 5 parts by weight with respect to 100 parts by weight of the aromatic polyester.

Further, with respect to the composition of the present invention, as long as the object of the present invention is not impaired, antioxidants, heat stabilizers, ultraviolet absorbers, lubricants, release agents, coloring agents including dyes and pigments, nucleating agents, etc. One or more kinds of the additives can be added. Also small amounts of other thermoplastic resins (eg polycarbonate, polyamide, polypropylene, polyethylene, ethylene / propylene copolymers, ethylene / butene-1 copolymers, ethylene / propylene / non-conjugated diene copolymers, ethylene / ethyl acrylate copolymers). Polymer, ethylene / glycidyl methacrylate copolymer, ethylene / vinyl acetate / glycidyl methacrylate copolymer, ethylene / propylene-g-
Maleic anhydride copolymers, etc.) can also be added.

The method for producing the composition of the present invention is not particularly limited, but an aromatic polyester, a brominated phenoxy resin, a low molecular weight brominated epoxy compound, an antimony compound and, if necessary, other additives are used in an extruder. A method of melt kneading is preferable.

<Examples> The effects of the present invention will be described in more detail below with reference to Examples.

Examples 1-9, Comparative Examples 1-11 8 parts by weight of antimony trioxide, 100 parts by weight of polybutylene terephthalate having a relative viscosity of 1.75, the following brominated phenoxy resins (Br-PH) (a) to (d) and / or Alternatively, the low-molecular weight brominated epoxy compounds (Br-EP) (e) to (h) shown in Table 1 were mixed in a V-blender and then melt-kneaded-pelletized at 250 ° C. using a 40 mmφ extruder. After drying this pellet, a load of 216 is applied according to ASTM D-1238.
0 g, cylinder temperature 260 ° C., heating time 8 minutes and 3
25 minutes with 0 minute melt flow rate (MFR)
Using a 5 ounce screw in-line injection molding machine set at 0 ° C, mold temperature 80 ° C, molding cycle (injection time / cooling time / intermediate time) 10 seconds / 15 seconds / 10 seconds (molding cycle )), ASTM-1 dumbbell,
1/8 "width Izod impact test piece and combustion test piece (1
/ 16 ″ × 1/2 ″ × 5 ″) was obtained, and the molding lower limit pressure (gauge pressure), which is the minimum pressure required to completely fill the mold, was determined.

Also, molding cycle (injection time / cooling time / intermediate time)
Was changed to 10 seconds / 15 seconds / 140 seconds (molding cycle (b)) and other conditions were the same, and two kinds of test pieces were obtained in the same manner as above.

For these test pieces, vertical combustion test according to UL94 standard, tensile test according to ASTM D638, ASTM D256
According to the above, an Izod impact test was performed, and a weight loss measurement after 60 minutes at 260 ° C. was performed under a nitrogen stream using a thermogravimetric analyzer manufactured by Dyupon. The tensile test pieces of the molding cycle (a) were heat treated in an oven at 180 ° C for 200 hours,
Further, a tensile test was conducted. The results are shown in Table 1.

(Flame retardant (a) ~ (h))

General formula (In the formula, s represents a number obtained by subtracting 1 from the average degree of polymerization.) In the brominated epoxy compound, the flame retardants (a) to (h) are such that s has the following values.

From the examples in Table 1, the brominated phenoxy resin having a degree of polymerization of 20 or more and the low molecular weight brominated epoxy compound having a degree of polymerization of 10 or less according to the present invention have an average degree of polymerization of 4.5 / 1 to 30 /
It can be seen that when a specific amount is used together in the range of 1, a flame-retardant polyester composition excellent in flame retardancy, mechanical properties, molding retention stability, molding fluidity and heat resistance can be obtained.

On the other hand, Comparative Examples 1 to 3 show that the brominated phenoxy resin alone has poor mechanical properties such as a small elongation at break and poor molding fluidity and retention stability. Further, when the amount of the low molecular weight brominated epoxy compound relative to the brominated phenoxy resin is too large, problems such as an increase in gas generation amount, thickening during molding retention and gelation occur (Comparative Examples 4 to 4).
6). From Comparative Examples 7 and 8, it can be seen that when the ratio of the average degree of polymerization of the brominated phenoxy resin and the low molecular weight brominated epoxy compound is out of the range of the present invention, problems such as heat resistance and retention stability occur. Further, when the average degree of polymerization of the low molecular weight brominated epoxy compound is too large (Comparative Example 9), the retention stability is lowered, and when the degree of polymerization of the brominated phenoxy resin is too small (Comparative Example 10), the mechanical stability is low. A flame-retardant polytestel composition having good performance cannot be obtained, because properties, heat resistance, etc. are deteriorated, and when acrylic rubber is used in combination, tensile strength, heat resistance, etc. are deteriorated.

Examples 10 to 13 and Comparative Examples 12 to 17 100 parts by weight of polybutylene terephthalate having a relative viscosity of 1.47, 50 parts by weight of a glass fiber (3 mm length) of a stranded type, 8 parts by weight of antimony trioxide and the above-mentioned difficulty. The amounts of the flame retardants (a) to (h) shown in Table 2 were dry blended with a tumbler, and melt mixing, injection molding (however, molding temperature was 260 ° C.) and characteristic evaluation were performed in the same manner as in Example 1. The results are shown in Table 2.

As is clear from the examples of Table 2, when a brominated phenoxy resin having a specific degree of polymerization and a low molecular weight brominated epoxy compound of the present invention are used together in a specific amount at a specific degree of polymerization even when glass fibers are blended. Shows that a flame-retardant polyester composition excellent in flame retardancy, mechanical properties, molding retention stability, molding fluidity and heat resistance can be obtained.

<Effects of the Invention> Brominated phenoxy resin having a specific degree of polymerization and low molecular weight brominated epoxy compound are used together with an antimony compound in an aromatic polyester so that both have a specific degree of polymerization and a weight ratio. A molded article obtained from the flame-retardant polyester composition of the present invention, which has been obtained at least, has good flame retardancy and is excellent in mechanical properties, molding retention stability, molding fluidity and heat resistance. It is useful as an electronic device component.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display area C08L 71:10)

Claims (1)

[Claims] 1. (A) Aromatic polyester (B) Brominated phenoxy resin having a skeleton represented by the following general formula (I) (Alkylene group for X C ₁ ~ ₁₀ in the above formula (I), an alkylidene group, a carbonyl group, -O -, - S- or -S
O ₂ −, n represents an integer of 20 or more. ) (C) A low molecular weight brominated epoxy compound represented by the following general formula (II) and (In the formula, X is the same as the substituent of the formula (I), p and q each represent an integer of 1 to 4, and n ′ represents an integer of 0 to 10.) (D) Composition comprising antimony compound The total amount of the component (B) and the component (C) is 2 to 50 parts by weight, and the component is 100 parts by weight of the component (A).
The weight ratio (B) / (C) of (B) and component (C) is 95/5 to 50/50.
Component (D) is 1 to 50 parts by weight, and component (B)
And the degree of polymerization of component (C) [n / (n '+ 1)] is 4.5 / 1
A flame-retardant polyester composition, characterized in that it is ˜30 / 1.