JPH03281566A - Preparation of flame-retardant resin composition - Google Patents

Abstract

PURPOSE:To prepare the subject composition having excellent flame retardance, heat-resistance, mechanical properties, etc., by preparing a highly flame retardant-containing composition from a liquid-crystalline polyester and the polymeric flame-retardant and subsequently melt-blending the composition with the liquid-crystalline polyester. CONSTITUTION:A liquid-crystalline polyester containing ethylenedioxy units as an essential component and having a melting viscosity of 10-15000 poises is melt-blended with a polymeric flame-retardant (e.g. brominated polycarbonate or brominated epoxy compound) in a weight ratio of 9/1-4/6, and the prepared composition containing the polymeric flame-retardant in a high concentration is melt-blended with the liquid crystalline polyester in a weight ratio of (0.2-30)/100 to provide the objective composition.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides excellent flame retardancy and good heat resistance.
The present invention relates to a flame-retardant polyester composition with excellent visual quality and molded product appearance.

<Conventional technology> In recent years, the demand for higher performance plastics has been increasing, and many polymers with various new performances have been developed and put on the market. Optically anisotropic liquid crystal polymers have attracted attention for their excellent fluidity and mechanical properties, and are used in mechanical parts, electrical and
Applications are being expanded to include electronic components.

On the other hand, in addition to the general chemical and physical property balance, these industrial materials are strongly required to have flame safety, that is, flame retardancy.

Generally, liquid crystal polymers have flame resistance and are known to have the property of self-foaming to form a carbonized layer when directly exposed to flame.

However, liquid crystal polyesters made by copolymerizing acyloxy aromatic carboxylic acids with polyesters obtained from alkylene glycols and dicarboxylic acids (for example,
-18016.

That is, the present invention provides a method for producing a flame-retardant resin composition in which 100 parts by weight of liquid crystal polyester is mixed with 0.2 to 30 parts by weight of a polymeric flame retardant. Producing a high-concentration polymer broiler agent composition with a range of 9/1 to 4/6 by melt-kneading,
The present invention relates to a method for producing a flame-retardant resin composition, which is characterized in that the composition and liquid crystal polyester are then melt-kneaded and adjusted to a desired blending ratio.

The liquid crystal polyester referred to in the present invention is a melt moldable liquid crystal polyester comprising units selected from aromatic oxycarboxylate units, aromatic dioxy units, aromatic dicarbonyl units, ethylene dioxy units, etc. Supplementary units are polyesters selected from ■~■.

1++O+ +O-R+ -0+- 1+0-CH2CH2-0-)- +C0-R2-C0-)- ......ri...0 ............tag( However, R1 in the formula represents one or more groups selected from ←gφ〉−〈琵)←H3, and R2 represents one or more groups selected from, provided that X in the formula is a hydrogen atom. or represents a chlorine atom, and the structural unit (■) is substantially equimolar to the structural unit [■±0]. ) Among these, the structural unit [■10] is most preferably composed of [■10■
+0], preferably 82 to 95 mol%
It is 3 mol%, more preferably 85 to 90 mol%.

In addition, the structural unit (■) is 25 to 5 mol% of [■10■+0], preferably 18 to 7 mol%, more preferably 15
~10 mol%. Structural unit [■10■] is [■＋■＋
If it is larger than 95 mol % of [0], the melt fluidity will decrease and it will solidify during polymerization, and if it is smaller than 75 mol %, the heat resistance will be poor, which is not preferable.
/25-9515, preferably 78/22-93
/7. If it is less than 75/25 or larger than 9515, the heat resistance and fluidity will be poor and the object of the present invention cannot be achieved. Equimolar.

The method for producing the liquid crystal polyester used in the present invention is not particularly limited, and it can be produced according to known polyester polycondensation methods.

Furthermore, the melt viscosity of the liquid crystal polyester used in the present invention is 1
0-15. OOO boys are preferred, especially 20 to 5.
000 voids is more preferred.

This melt viscosity is a value measured using a Koka type flow tester under conditions of (liquid crystal starting temperature +40°C) and a slip rate of 1,000 (1/sec).

On the other hand, the logarithmic viscosity of this thermotropic liquid crystalline polyester is 0, which can be measured in pentafluorophenol at an Ig/d concentration of 60°C, and the polyester consisting of IN structural units ■~0 has a logarithmic viscosity of 0.5 to 5° Oa/g. Preferably, 1
, 0-3. OdR/t is particularly preferred.

The polymer flame retardant used in the present invention is a bromine atom and/or
Or it is a polymer containing a phosphorus atom, and the bromine content is 20! as a brominated polymer flame retardant! E amount% or more is preferred, specifically brominated polycarbonate (for example, polycarbonate oligomer produced using brominated bisphenol A or its copolymer with bisphenol A), brominated epoxy compound (for example, brominated bisphenol jepoxy compounds produced by the reaction of A with epichlorohydrin and monoepoxy compounds produced by the reaction of brominated phenols with epichlorohydrin), poly(brominated benzyl acrylate),
Examples include halogenated polymers, oligomers, or mixtures such as brominated polyphenylene ether, brominated bisphenol A, condensates of cyanuric chloride and brominated phenol, brominated polystyrene, crosslinked brominated polystyrene, and crosslinked brominated polyα-methylstyrene. Among them, brominated epoxy oligomers or polymers, brominated polystyrene, crosslinked brominated polystyrene, brominated polyphenylene ether and brominated polycarbonate are preferred, and brominated polystyrene is particularly preferably used.

The amount of these polymeric flame retardants added is 10% of the liquid crystal polyester.
0 parts by weight, preferably 0.2 to 30 parts by weight, more preferably 0.5 to 20 parts by weight, but flame retardancy is closely related to the amount of copolymerization of the structural unit 0 of the liquid crystal polyester. When containing the structural unit (■), it is preferable to add the following amount; that is, the amount of the brominated polymer flame retardant added is 60 to 280 parts by weight per 100 parts by weight of the structural unit (■) in the liquid crystal polyester. Part is preferable, and 100 to
200 parts by weight is particularly preferred.

On the other hand, examples of the phosphorus-based polymer flame release agent used in the present invention include polymers having the following structural units.

1 R1 Among these, the most preferred organic phosphorus compounds are the following polymers.

Note that some of these polymers may be metal salts.
The amount of this polymer added is 0.2 to 30 parts by weight per 100 parts by weight of liquid crystal polyester consisting of structural formulas ○, ■, 0 and ■.
Part by weight, preferably 05 to 15 parts by weight, and 2 to 1 part by weight per 100 parts by weight of the structural unit (■) in the liquid crystalline polyester.
50 parts by weight is preferred, and 10 to 100 parts by weight are particularly preferred.

Further, the polymeric flame retardant in the present invention may be a polymer containing bromine and phosphorus atoms, such as a polymer consisting of the following structural unit.

When the liquid crystal polyester of the present invention contains the structural unit 0, the structural unit ■ is 5 of the structural units [■+■10■]
~25 mol%, and with the above added amount of flame retardant, it is possible to achieve V-0 with a thickness of 1/32" in the UL94 standard vertical combustion test (ASTM D790 standard).The structural unit ■ is less than 5 mol% However, since the melting point of the liquid crystal polyester becomes high, the flame retardant decomposes the liquid crystal polyester during melting, resulting in a decrease in polymerization, and even if a filler is added, the mechanical properties may deteriorate, and the molded product may drip during combustion. do not have.

On the other hand, if the structural unit (■) is more than 25 mol%, not only will heat resistance such as deflection temperature under load be greatly reduced, but it may be necessary to add a large amount of organic bromine compound or phosphorus compound to impart flame retardance. This is not preferable since it is necessary to further add a flame retardant aid such as an antimony compound, which greatly reduces heat resistance and mechanical properties.

In the resin composition of the present invention, the weight ratio of liquid crystal polyester to polymeric flame retardant is 9/1 to 4/6, preferably 87.
It is necessary to produce a composition with a high concentration of polymeric flame retardant in the range of 2 to 515 by melt-kneading, and then melt-knead this composition and liquid crystal polyester to adjust the desired blending ratio. When the weight ratio of the polymeric flame retardant is less than 4/6, the dispersibility of the polymeric flame retardant is poor, so flame retardancy, heat resistance, mechanical properties, etc. are not sufficient, which is not preferable.

Brominated polystyrene, which is the most preferred polymeric flame retardant in the present invention, can be dispersed in the liquid crystal polyester (A) with an average diameter of 2.5 μm or less.

A composition in which a filler is further contained in the liquid crystal polyester and flame-retardant liquid crystal polyester composition used in the present invention can be more preferably used in the present invention. When a filler is added, the amount added is preferably 200 parts by weight or less, particularly preferably 15 to 150 parts by weight, based on 100 parts by weight of the liquid crystal polyester. Although the filler may be added at any time, it is preferable to add the filler after the flame retardant and liquid crystal polyester have been mixed in advance.

Fillers that can be used in the present invention include glass fibers, carbon fibers, aromatic polyamide fibers, potassium titanate fibers, gypsum fibers, yellow #I fibers, stainless steel fibers, steel fibers, ceramic fibers, boron whisker fibers, and mica fibers. , talc, silica, calcium carbonate, glass peas, glass flakes, glass microballoons, clay, wollastenite, titanium oxide, and other fibrous, powder, granular, or plate-like inorganic fillers.

Among the fillers mentioned above, glass fibers are preferably used. The type of Karas* fiber is not particularly limited as long as it is generally used for reinforcing VJ fat, and can be selected from, for example, long fiber type, short fiber type chopped strand, milled fiber, etc. Additionally, the glass fibers may be coated or bundled with a thermoplastic resin such as ethylene/vinyl acetate copolymer, a thermosetting resin such as an epoxy resin, or a coupling agent such as a silane type or titanate type, or other It may be treated with a surface treatment agent.

Furthermore, the composition of the present invention may contain antioxidants, heat stabilizers (for example, hindered phenol, hydroquinone, phosphites, and substituted products thereof), ultraviolet absorbers, etc., to the extent that the objects of the present invention are not impaired. agents (e.g. resorcinol, salitate, benzotriazoles,
benzophenone), lubricants and mold release agents (such as montanic acid and its salts, its esters, its half esters, stearyl alcohol, stearamide and polyethylene waxes), dyes (such as nidrodium) and pigments (such as cadmium sulfide, phthalocyanines,
Conventional additives such as colorants (including carbon black, etc.), plasticizers, antistatic agents, and other thermoplastic resins can be added to impart desired properties.

Known methods can be used for melt-kneading the resin composition of the present invention. For example, using a Banbury mixer, rubber roll machine, kneader, single screw or twin screw extruder, etc.
The composition can be prepared by melt-kneading at a temperature of 200 to 350°C. At this time, the filler or flame retardant can be supplied by using a single-screw or twin-screw extruder, and feeding the filler or flame retardant from a side feeder in the middle of the extruder for kneading.

<Example> Hereinafter, the present invention will be explained in detail with reference to Examples.

Reference Example 1 881 parts by weight of p-hydroxybenzoic acid, 158 parts by weight of 4.4-dihydroxybiphenyl, 907 parts by weight of ice-free acetic acid, 141 parts by weight of terephthal'ei, and an intrinsic viscosity of about 0.
．． 6alt polyethylene terephthalate 2453! A certain amount of the mixture was charged into a reaction vessel equipped with a stirring blade and a distillation tube, and acetic acid depolycondensation was carried out under the following conditions.

First, under a nitrogen gas atmosphere at 100 to 250°C for 5 hours,
After reacting at 50-300℃ for 1.5 hours, 300℃
When the pressure was reduced to 0.5 Hg in 1 hour and the reaction was further carried out for 2.25 hours to complete the polycondensation, almost a theoretical amount of acetic acid was distilled out, resulting in a resin (a) having the following theoretical structural formula. I got it.

K/fl/m,/n = 75/10
/ 15 / 25 In addition, this polyester was placed on the sample stage of a polarizing microscope and the temperature was raised to confirm the optical anisotropy. As a result, the liquid crystal onset temperature was 264 ° C, indicating good optical anisotropy. Ta. Logarithmic viscosity of this polyester (0-!
in pentafluorophenol at a concentration of r/d1 at 60°C.
) was 1.96 a/g, and the melt viscosity at 304°C and a sliding speed of 1,000 (1/sec) was 910 voids.

Example 1 30 parts by weight of the resin (a) obtained in Reference Example 1 and 7.5 parts by weight of brominated polystyrene ('1 Pyrocheck' 68 PB, manufactured by Nissan Fellow ■) were added to a 30 mφ tube set at 300°C.
The mixture was melt-mixed and pelletized using a twin-screw extruder.

37.5 parts by weight of this pellet and 70 parts of the resin obtained in Reference Example 1
Parts by weight and 45 parts by weight of glass fibers were melt-mixed and pelletized using a 30 wφ twin screw extruder set at 300°C.

Next, the obtained pellet was subjected to a Sumitomo Nestal injection molding machine Gromat 40/25 (manufactured by Sumitomo Heavy Industries, Ltd.), and combustion test pieces (1/32" and 1 /8" x 1/2" x 5") and bending test (1/8"
A vertical combustion test was conducted according to the L92 standard.

As a result, the polyester blended with the organic bromine compound of the present invention had a flammability of 1/32"■-0 and a bending strength of 1.8
It was found that the molded product had excellent mechanical and thermal properties and a good appearance.

Then, molding was carried out after residence at 310℃ for 20 minutes in a molding machine, and the retention stability was examined, and the bending strength was 188.
91qr f/CIl! It was found that there was almost no deterioration in physical properties.

On the other hand, scanning electron microscopy (SEM) of the fractured surface of this molded product and transmission electron microscopy (TEM) of ultrathin sections of the molded product revealed that the flame retardant was dispersed in a spherical shape with an average diameter of 1 μm. .

Comparative Example 1 30 parts by weight of 100 parts by weight of the resin (a) obtained in Reference Example 1, 7.5 parts by weight of brominated polystyrene (Pavai Mouth Check 68 P B, manufactured by Nissan Fellow ■) and 45 parts by weight of glass m fiber.
Melt-mix and pelletize using a 30ffIIIφ twin-screw extruder set at 0°C.

Then, evaluation was performed after injection molding in the same manner as in Example 1, and the flame retardancy was 1/32"V-2, the bending strength was 1,
It was 845 krf/-.

As in Example 1, the retention stability was examined after 20 minutes in the molding machine and found to be 1,580 ktrf/aa.

On the other hand, when the dispersion of the flame retardant in this molded article was examined in the same manner as in Example 1, the average diameter was 5 μm.

<Effects of the Invention> The flame retardant polyester composition of the present invention provides flame retardancy, i.
Injection molded products with excellent mechanical properties and heat resistance can be obtained.

Patent Application Daito Co., Ltd. Procedural Amendment 1, Indication of the Case 1990 Patent Review No. 854 2, Title of the Invention 7, Contents of the Amendment (1) Page 2 of the specification tube, line M1 to line tN ``Flame retardant "Polyester composition" is corrected to "Flame-retardant resin composition."

(2) Page 3, lines 13 to 14, "Flame retardant polyester composition j" is referred to as "flame retardant resin composition"
and correct it.

(3) On page 7, line 4, "of the structural unit (IV)" is amended to "the structural unit (IV) is."

(4) On page 9, line 6, "polymer flame retardant side" is corrected to "brominated polymer flame retardant."

(5) Page 10, line 1 ``　　0 1 +R, -0-R20←, 0R1” “　　O I +P OR20←, 0R1”.

(6) Page 10, line 2 0=P+ -.

+O-Ar　-0゜ -CR+ CO← 2 -CO← ” of 'o=p-.

10O-Ar　-0゜ CFtx CO← -CO← (however, R1 is a hydrogen atom or a monovalent organic residue of, 2 indicates a divalent organic residue.

) ” and correct it.

(7) Page 10, line 5 ``　　0 ■ +R,=O−R2o+1 0R1” “　　O +1 ÷P-0-R20← OR.

(However, R2 is a hydrogen atom or a monovalent sPi group,
R2 represents a divalent m-residue.)" is corrected.

(8) In the 13th line from the bottom of page 11, "of the present invention" is amended to read "of the present invention (wherein R1 represents a hydrogen atom or a monovalent organic residue)".

(9) Page 15, line 1 Correct "nidrodium" to "nigrosine".

hand Continued Supplementary 'LL shomeng (shaku) 1. Things subject of table No 1990 Patent Application No. 854 Departure Akira of given name name Method for producing flame retardant resin composition

Claims (2)

[Claims] (1) 100 parts by weight of liquid crystal polyester and 0 polymer flame retardants
．． In the method for producing a flame retardant resin composition in which 2 to 30 parts by weight of the liquid crystalline polyester and the polymer flame retardant are mixed, first, a polymer flame retardant polymer having a weight ratio of liquid crystal polyester and polymer flame retardant in the range of 9/1 to 4/6 is used. 1. A method for producing a flame-retardant resin composition, which comprises producing the composition by melt-kneading, and then melt-kneading the composition and liquid crystal polyester to adjust the composition to a desired blending ratio. (2) The method for producing a flame-retardant resin composition according to claim 1, wherein the liquid crystalline polyester contains an ethylenedioxy unit as an essential component.