JP3388854B2 - Flame retardant resin composition - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel flame-retardant resin composition, and more particularly to a method for maintaining good moldability and physical properties of a styrene-based flame-retardant resin. A flame-retardant resin composition having excellent surface scratch resistance, improved thermal stability during molding, and suitable as a molding material for large and thin-walled products requiring good appearance and flame retardancy. It is. [0002] Hitherto, styrene-based flame-retardant resins have been widely used as general-purpose resins in various molded articles requiring flame retardancy, but are inferior in scratch resistance, so that they are used in television cabinets and the like. In applications where a good appearance is required, the actual condition is that the surface of the molded product is usually coated with an acrylic paint or the like. However, in this case, it is inevitable that the coating cost is high, and it has been desired to improve the scratch resistance of the flame-retardant resin itself. In the case of thin and large products,
In many cases, the resin is molded at a high temperature in order to improve the fluidity of the resin. In this case, the thermal stability of the resin needs to be increased. [0003] In order to achieve a practically scratch-resistant level without painting, a pencil hardness of HB or more is required. However, the pencil hardness of a styrene-based flame-retardant resin currently used is 3B.
About 4B. The pencil hardness of flame-retardant ABS resin is B
~ HB, but poor fluidity, making it difficult to mold large and thin products. On the other hand, in a system in which a flame retardant is added to polymethyl methacrylate, although the hardness is sufficient,
There is a disadvantage that the fluidity and impact resistance are poor. On the other hand, as a method of improving the surface hardness of a molded product, a method of insert-molding a film such as polymethyl methacrylate at the time of injection molding and bonding the film to the surface is known. In addition to this, there are drawbacks such as the necessity of complicated equipment, the formation of wrinkles easily in a molded product having a large depth, and the necessity of post-processing in the case of a molded product having a lattice or the like. [0005] Incidentally, among the styrene-based flame-retardant resins currently used, antimony trioxide is widely used as a flame-retardant aid together with a bromine-based flame retardant. However,
Antimony trioxide can be obtained in different crystal forms depending on the manufacturing method, and has different thermal stability depending on the crystal form. Therefore, when molding at high temperature, there is a problem that a defective phenomenon such as silver streak often occurs. [0006] Under such circumstances, the present invention maintains good moldability and physical properties of a styrene-based flame-retardant resin and has excellent surface scratch resistance. Provided is a flame-retardant resin composition which has improved thermal stability during molding, does not require coating on molded products, and is suitable as a molding material for large and thin-walled products requiring good appearance and flame retardancy. It was done for the purpose of doing. The present inventors have conducted intensive studies to develop a flame-retardant resin composition having the above-mentioned preferable properties. The purpose can be achieved by blending a brominated flame retardant and a specific antimony trioxide at predetermined ratios with respect to a rubber-modified copolymer component comprising a methacrylate unit and a predetermined rubbery polymer. This led to the completion of the present invention based on this finding. That is, the present invention relates to a polymer comprising (A) 25 to 86% by weight of an aromatic vinyl compound unit, (B) 10 to 60% by weight of a methacrylate unit, and (C) a butadiene unit. (B) 3 to 30 parts by weight of a brominated flame retardant and (C) orthorhombic based on 100 parts by weight of an elastomer-modified copolymer component comprising 4 to 15% by weight of an elastomer composed of a partially hydrogenated product thereof. Content of 30%
An object of the present invention is to provide a flame-retardant resin composition comprising 1 to 12 parts by weight of the following antimony trioxide. In the composition of the present invention, as the component (A), a polymer containing (a) an aromatic vinyl compound unit, (b) a methacrylate unit and (c) a butadiene unit, and / or a partially hydrogenated polymer thereof. An elastomer-modified copolymer component comprising an elastomer made of a product is used. In this elastomer-modified copolymer component, the content of the aromatic vinyl compound unit (a) is 2
It is selected in the range of 5 to 86% by weight, preferably 30 to 75% by weight. If the content is less than 25% by weight, good moldability and physical properties of the styrene resin cannot be maintained, and if it exceeds 86% by weight, the content of other units (b) and (c) decreases. Insufficient scratch resistance or impact resistance. A monomer forming the aromatic vinyl compound unit (hereinafter, also referred to as a vinyl aromatic monomer)
As, for example, styrene, α-methylstyrene, vinyltoluene, vinylethylbenzene, vinylxylene,
Examples thereof include pt-butylstyrene, α-methyl-p-methylstyrene, and vinylnaphthalene. These may be used alone or in combination of two or more. Among these monomers, styrene and α-methylstyrene are preferred. The content of the methacrylate unit (b) is 10 to 60% by weight, preferably 20 to 5% by weight.
It is selected in the range of 6% by weight. If the content is less than 10% by weight, the scratch resistance is insufficient, and if it exceeds 60% by weight, the fluidity and the moldability deteriorate. Examples of the monomer forming the methacrylate unit include alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate and isobutyl methacrylate. These may be used alone or in combination of two or more. Among these monomers, methyl methacrylate is preferred. The elastomer of the component (C) is, for example, polybutadiene, styrene-butadiene copolymer, partially hydrogenated product thereof, or a mixture thereof, and the content thereof is 4 to 15% by weight, preferably 5 to 15% by weight. ~ 14% by weight. If the content is less than 4% by weight, the impact strength is insufficient, and if it exceeds 15% by weight, the scratch resistance decreases. The elastomer-modified copolymer component (A) is preferably obtained by copolymerizing a vinyl aromatic monomer and a methacrylic acid ester in the presence of the elastomer (C). The polymerization method is not particularly limited, and a conventionally used method such as an emulsion polymerization method, a bulk polymerization method, a solution polymerization method, a suspension polymerization method, or a multi-stage polymerization method such as a bulk-suspension two-stage polymerization method, etc. Can be used. In the composition of the present invention, the elastomer-modified copolymer of the component (A) may be used alone or in combination of two or more. In the composition of the present invention, the brominated flame retardant used as the component (B) includes, for example, decabromodiphenyl ether, tetrabromobisphenol A, tetrabromobisphenol S, bistribromophenoxyethane, polydibromophenylene oxide, tetrabromo Bisphenol A epoxy polymer, tetrabromobisphenol A carbonate oligomer, polytribromostyrene, hexabromocyclododecane, hexabromobenzene, ethylenebistetrabromophthalimide,
Among them, tetrabromobisphenol A epoxy polymer, especially, of the general formula (I): (R in the formula is a compound of the formula Or the formula And n represents 0 or a natural number of 10 or less.
And a tetrabromobisphenol A epoxy-modified oligomer represented by the following general formula (I):
I) (Wherein n and m represent an integer of 1 to 5) and decabromodiphenyl ether are preferred. In the composition of the present invention, the brominated flame retardant of component (B) may be used alone or in combination of two or more. It is necessary to select the compounding amount in the range of 3 to 30 parts by weight based on 100 parts by weight of the component (A), that is, the elastomer-modified copolymer component. If the amount is less than 3 parts by weight, the flame retardancy is insufficient, and if it exceeds 30 parts by weight, the impact resistance tends to decrease. In the composition of the present invention, antimony trioxide used as the component (C) acts as a flame retardant auxiliary,
In order to improve the thermal stability during molding, the content of the orthorhombic system must be 30% or less. In the composition of the present invention, the compounding amount of the flame retardant auxiliary of the component (C) is 1 to 12 parts by weight, preferably 2 to 100 parts by weight of the component (A), that is, 100 parts by weight of the resin component.
It is necessary to select in the range of ８8 parts by weight. If the amount is less than 1 part by weight, the flame retardancy is insufficient, and if it exceeds 12 parts by weight, the scratch resistance and the impact resistance tend to decrease. The composition of the present invention may contain various known additives as needed, for example, inorganic fillers such as calcium carbonate, talc, mica, silica, and asbestos, and glass fibers as long as the object of the present invention is not impaired. And additives such as reinforcing agents such as carbon fibers and metal whiskers, antioxidants, ultraviolet absorbers, heat stabilizers, lubricants, and antistatic agents. The composition of the present invention comprises, for example, the component (A)
The component (B), the component (C) and various additional components used as necessary are blended at predetermined ratios, respectively, and a Banbury mixer, a single screw extruder, a twin screw extruder, a coneder, and a multi-screw extruder are used. It can be prepared by sufficiently kneading with a machine or the like. The composition of the present invention thus obtained is
For example, a molded article having a desired shape can be formed according to a generally used method such as an injection molding method or an extrusion molding method. The flame-retardant resin composition of the present invention retains good moldability and physical properties of a styrene-based flame-retardant resin, has excellent surface scratch resistance, and suppresses conventional scratch resistance. Large-sized and thin-walled products that require good appearance and flame retardance are required because housings, which had to be coated with acrylic, etc., can be made unpainted and thermal stability during molding is improved. It is suitably used as a molding material for products, particularly as a housing material in the field of electric equipment and OA equipment. Next, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples. The samples of the examples and comparative examples were evaluated as follows. (1) Melt index (MI): JIS K-72
It was determined under the conditions of 200 ° C. and a load of 5 kg according to 10. (2) Izod impact value (Izod): JIS K-7
Determined according to 110. (3) Pencil hardness: determined according to JIS K-5400. (4) Flame retardancy: evaluated according to UL94. (5) Thermal stability: The presence or absence of molding defects such as silver streaks in the molded products was visually evaluated according to the following criteria. Thermal stability evaluation criteria ：: No abnormality in appearance ○: Slight silver streak generation ×: Silver streak generation on entire surface Manufacturing Example 1 NF35AS (trade name,
385 g of polybutadiene manufactured by Asahi Kasei Corporation and 255 of styrene
5 g, 560 g of methyl methacrylate, 7 g of benzoyl peroxide as a polymerization initiator, and 7 g of t-dodecyl mercaptan as a chain transfer agent, and 400 rpm
While stirring, a bulk polymerization reaction was performed at 90 ° C. to a conversion of 40%. Then, 3000 g of this reaction mixture was added to 1
Into an autoclave of 0 l, 4000 g of water, 6 g of polyvinyl alcohol as a suspension stabilizer, and 16.5 g of benzoyl peroxide and 2.1 g of dicumyl peroxide as a polymerization initiator, and stirring at 500 rpm, from 60 ° C to 20 ° C / 140 ° C at a heating rate of hr
, And the mixture was further reacted at this temperature for 3 hours to carry out suspension polymerization. The composition thus obtained was formed into beads, extruded by a single screw extruder at 220 ° C., and pelletized to form an elastomer-modified copolymer (hereinafter, referred to as a copolymer) a.
Got. Production Example 2 A bulk polymerization reaction was carried out in the same manner as in Production Example 1 except that the amounts of polybutadiene, styrene and methyl methacrylate were changed to 210 g, 2240 g and 1050 g, respectively. A suspension polymerization was carried out in the same manner as in Production Example 1 except that the amount was changed to 0 g, and then a copolymer b was obtained in the same manner as in Production Example 1. Production Example 3 The amounts of styrene and methyl methacrylate were
Except having changed to 0 g and 1470 g, it carried out similarly to manufacture example 2, and obtained copolymer c. Comparative Production Example 1 The amounts of styrene, methyl methacrylate and benzoyl peroxide during suspension polymerization were 3010 g and 280 g, respectively.
And a copolymer w for comparison was obtained in the same manner as in Production Example 2 except that the amount was changed to 12.0 g. Comparative Production Example 2 The amounts of styrene, methyl methacrylate and benzoyl peroxide during suspension polymerization were 910 g and 2380 g, respectively.
And a copolymer x for comparison was obtained in the same manner as in Production Example 2 except that the amount was changed to 6.0 g. Comparative Production Example 3 A copolymer y for comparison was produced in the same manner as in Production Example 2 except that the amounts of polybutadiene, styrene and methyl methacrylate were changed to 105 g, 2380 g and 1015 g, respectively.
Got. Comparative Production Example 4 The amounts of polybutadiene, styrene, methyl methacrylate and benzoyl peroxide during suspension polymerization were each 59
A copolymer z for comparison was obtained in the same manner as in Production Example 2 except that the amounts were changed to 5 g, 1820 g, 1085 g, and 15.0 g. The composition (shown in percentage) and MI of the above copolymer
Are shown in Table 1. [Table 1] Example 1 100 parts by weight of the copolymer a obtained in Production Example 1, Pratherm E
C14 [trade name, manufactured by Dainippon Ink and Chemicals, Inc., tetrabromobisphenol A epoxy oligomer (bromine content: 59% by weight)] (hereinafter referred to as flame retardant (1)) 12 parts by weight and orthorhombic content 0 After dry blending 8 parts by weight of 0.2% antimony trioxide, the mixture was kneaded using a kneading machine NVC-50 manufactured by Nakatani Machinery Co., Ltd., and then Toshiba Machine Co., Ltd.
Using IS200CN manufactured, the sample was retained at 280 ° C. for 5 minutes, and then a test piece having a shape of 100 × 420 × 3 mm was formed. For this test piece, a melt index (MI: JIS K-7210, 200 ° C., load 5)
kg), Izod impact value (Izod: JIS K-7)
110), pencil hardness (JIS K-5400), flame retardancy and thermal stability. Table 2 shows the results. Example 2 The amounts of the flame retardant (1) and antimony trioxide were each adjusted to 20.
A test piece was obtained in the same manner as in Example 1, except that the parts were changed to parts by weight and 2 parts by weight. Table 2 shows the results of the same evaluation as in Example 1 for this. Example 3 A test piece was obtained in the same manner as in Example 2 except that copolymer b was used instead of copolymer a and the amount of antimony trioxide was changed to 5 parts by weight. Table 2 shows the results of the same evaluation as in Example 1 for this. Example 4 A test piece was obtained in the same manner as in Example 3 except that antimony trioxide having an orthorhombic content of 10.1% was used. Table 2 shows the results of the same evaluation as in Example 1 for this. Example 5 A test piece was obtained in the same manner as in Example 3 except that antimony trioxide having an orthorhombic content of 26.7% was used. Table 2 shows the results of the same evaluation as in Example 1 for this. Example 6 The amounts of the flame retardant (1) and antimony trioxide were each 28
A test piece was obtained in the same manner as in Example 4, except that the weight was changed to 10 parts by weight. About this, Example 1
Table 2 shows the results of the same evaluation. Example 7 20 parts by weight of the flame retardant (1) was mixed with SAYTEX8010 [trade name, manufactured by Ethyl Corporation, decabromodiphenylethane (bromine content: 82% by weight)] (hereinafter referred to as flame retardant (2)). A test piece was obtained in the same manner as in Example 4 except that the amount was changed to parts by weight. Table 2 shows the results of the same evaluation as in Example 1 for this. Example 8 Example 7 except that the amount of the flame retardant (2) was changed to 15 parts by weight.
A test piece was obtained in the same manner as described above. About this one,
Table 2 shows the results of the same evaluation as in Example 1. Example 9 The flame retardant (2) was Planelon DB102 (trade name, manufactured by Mitsui Toatsu Fine Co., Ltd., decabromodiphenyl ether (bromine content: 83% by weight)) (hereinafter referred to as flame retardant (3)).
A test piece was obtained in the same manner as in Example 8, except that the test piece was changed to. Table 2 shows the results of the same evaluation as in Example 1 for this. Example 10 Example 4 was repeated except that the copolymer c was used instead of the copolymer b.
A test piece was obtained in the same manner as described above. About this one,
Table 2 shows the results of the same evaluation as in Example 1. Comparative Example 1 A test piece was obtained in the same manner as in Example 2 except that 5 parts by weight of an antimony trioxide having an orthorhombic content of 39.9% was used. Table 3 shows the results of the same evaluation as in Example 1 for this. Comparative Example 2 A test piece was obtained in the same manner as in Comparative Example 1, except that 20 parts by weight of the flame retardant (1) was changed to 15 parts by weight of the flame retardant (2).
Table 3 shows the results of the same evaluation as in Example 1 for this. Comparative Example 3 A test piece was obtained in the same manner as in Example 4 except that the amount of the flame retardant (1) was changed to 2 parts by weight. Table 3 shows the results of the same evaluation as in Example 1 for this. Comparative Example 4 Example 4 except that the amount of the flame retardant (1) was changed to 35 parts by weight.
A test piece was obtained in the same manner as described above. About this one,
Table 3 shows the results of the same evaluation as in Example 1. Comparative Example 5 A test piece was obtained in the same manner as in Example 4 except that the amount of antimony trioxide was changed to 0.5 part by weight. Table 3 shows the results of the same evaluation as in Example 1 for this. Comparative Example 6 A test piece was obtained in the same manner as in Example 4 except that the amount of antimony trioxide was changed to 15 parts by weight. Table 3 shows the results of the same evaluation as in Example 1 for this. Comparative Examples 7 to 10 Test pieces were obtained in the same manner as in Example 4 except that the copolymer b was changed to the copolymer w to z. Table 3 shows the results of the same evaluation as in Example 1 for this. The types of the flame retardants shown in Tables 2 and 3 are as follows. Flame retardant (1): Pratherm EC14 [trade name, manufactured by Dainippon Ink and Chemicals, Inc., tetrabromobisphenol A epoxy oligomer (bromine content: 59% by weight)] Flame retardant (2): SAYTEX8010 [trade name, Ethyl Corporation Flame retardant (3): Planelon DB102 [trade name, manufactured by Mitsui Toatsu Fine Co., Ltd., decabromodiphenyl ether (bromine content: 83% by weight)] Table 2] [Table 3] From Table 2, it can be seen that all of the examples are excellent in any of the evaluations. As can be seen from Table 3, in the case of the comparative example, (i) if the content of the antimony trioxide in the orthorhombic system is too large, the thermal stability is reduced (Comparative Examples 1 and 2). When the amount is too small, the flame retardancy decreases, and when the amount is too large, the impact resistance decreases (Comparative Examples 3 and 4). (Iii) When the amount of the flame retardant aid is too small, the flame retardancy decreases and the amount is too large. However, the impact resistance is reduced (Comparative Examples 5 and 6). If the content of (ii) units in the (iv) elastomer-modified copolymer is too small, the pencil hardness is softened and the scratch resistance becomes insufficient. If the content is too large, the fluidity and moldability will be reduced (Comparative Examples 7 and 8), or if the content of the component (c) in the (v) elastomer-modified copolymer is too small, the impact resistance will be reduced, If the amount is too large, the pencil hardness is softened and the scratch resistance becomes insufficient (Comparative Examples 9 and 10). Examples of what is seen to be excellent in both of the evaluation.

Continuation of front page (72) Inventor Yutaka Tsubokura 1-1, Anesaki Beach, Ichihara-shi, Chiba Prefecture Idemitsu Oil Chemicals Co., Ltd. (56) References JP-A-5-247316 (JP, A) JP-A-4-311755 ( JP, A) JP-A-61-31451 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 51/04 C08K 3/22

Claims (1)

(57) [Claims] [Claim 1] (A) (A) Aromatic vinyl compound unit 2
5 to 86% by weight and (b) methacrylate unit 10
Elastomers 4-1 consisting of a polymer containing (a) butadiene unit and / or a partially hydrogenated product thereof, and
5% by weight of an elastomer-modified copolymer component 10
Flame retardancy comprising (B) 3 to 30 parts by weight of a brominated flame retardant and (C) 1 to 12 parts by weight of antimony trioxide having an orthorhombic content of 30% or less, based on 0 parts by weight. Resin composition.