JPH073096A - Flame-retardant resin composition - Google Patents

Abstract

PURPOSE:To provide a flame-retardant resin composition of high heat resistance, excellent in both fluidity and thermal stability in its molding operation, comprising a specific copolymer, specific graft copolymer and low-molecular weight vinyl chloride-based resin. CONSTITUTION:The objective composition comprising (A) a copolymer composed of (a) a copolymer from (1) 60-85wt.% of alpha-methylstyrene, (2) 15-40wt.% of acrylonitrile and (3) 0-20wt.% of another copolymerizable vinyl compound and (b) a second copolymer from (4) 25-85wt.% of styrene, 15-40wt.% of the component 2, <=60wt.% of the component 1 and (5) 0-20wt.% of another copolymerizable vinyl compound at the weight ratio a/b of (20:80) to (80:20), (B) a graft copolymer produced by grafting (c) 5-60 pts.wt. of a monomer mixture of (6) 10-90wt.% of a vinyl cyanide compound and/or alkyl (meth)acrylate, (7) 10-90wt.% of an aromatic vinyl compound and (8) 0-20wt.% of another copolymerizable vinyl compound to (d) 40-95 pts.wt. of a rubbery polymer and (C) a vinyl chloride resin 400-1000 in average degree of polymerization.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a flame-retardant resin composition having excellent heat resistance, fluidity, heat stability and flame retardancy. The present invention relates to a flame-retardant resin composition having extremely excellent fluidity and heat stability and good flame retardancy. Styrenic flame-retardant resins are used in various fields because of their excellent balance of heat resistance, impact resistance and processability. Among styrene-based resins, ABS-based flame-retardant resins prepared by blending vinyl chloride-based resins are particularly impact-resistant, flame-retardant and molded products as compared with ordinary ABS-based flame-retardant resins that use bromine-based flame-retardants. It has a feature of excellent external appearance, and recently, mainly in the field of OA equipment, this feature has been recognized, and the demand has remarkably increased.

[0002]

However, in the field of OA equipment, the demand for heat resistance is becoming stricter year by year, and in this respect, ABS flame-retardant resins which use vinyl chloride resin as a flame-retardant means have high heat resistance. There is a problem that it is low. Further, when an ABS resin copolymerized with α-methylstyrene or the like is used to improve heat resistance, the melt viscosity becomes high and the fluidity and thermal stability at the time of molding are remarkably lowered, resulting in many defects due to burns and foreign matters. There is a problem. Conventionally, in order to solve such problems of fluidity and thermal stability, a large amount of tin stabilizer, lubricant, antioxidant, etc. has been added. However, these methods often deteriorate the heat resistance of the resin and deteriorate the economical efficiency of the resin.

[0003]

DISCLOSURE OF THE INVENTION The present invention solves the above problems and provides a flame-retardant resin composition having high heat resistance and excellent fluidity and thermal stability during molding.

[0004]

The present inventors have found that stabilizers,
As a result of diligent studies on a method capable of solving these problems without adding a large amount of a lubricant or the like, surprisingly, a copolymer having a high α-methylstyrene content and a low molecular weight and a high α-methylstyrene content at a high content were obtained. The present invention has been completed by finding that when a copolymer having a molecular weight and a vinyl chloride resin having a low molecular weight are used in combination, the heat resistance is high, and the fluidity and the thermal stability are improved. That is, the present invention provides the following copolymers (A) 25 to 85
Parts by weight, and 5 to 40 parts by weight of the graft copolymer (B),
10 to 70 parts by weight of vinyl chloride resin (C) [however,
(A) + (B) + (C) = 100 parts by weight]. Copolymer (A): α-methylstyrene (a) 60 to 85
% By weight, 15-40% by weight of acrylonitrile (b), and 0-20 other vinyl compounds (c) copolymerizable with α-methylstyrene (a) or acrylonitrile (b).
A copolymer composed of 1% by weight and having a reduced viscosity of a methyl ethyl ketone soluble component in a dimethylformamide solution at 30 ° C.
In the range of 0.20 to 0.45 dl / g
1) and styrene (d) 25 to 85% by weight, acrylonitrile (e) 15 to 40% by weight α-methylstyrene (f) 60% by weight or less, and styrene (d), acrylonitrile (e) or α-methylstyrene Another vinyl compound (g) copolymerizable with (f), which is a copolymer consisting of 0 to 20% by weight, and has a reduced viscosity of a methyl ethyl ketone soluble component of 0.45 at 30 ° C. in a dimethylformamide solution.
The copolymer (A2) is in the range of 0.90 dl / g, and the weight ratio of the copolymers (A1) and (A2) is (A2).
1): a copolymer in which (A2) = 20/80 to 80/20, a graft copolymer (B): a rubbery polymer (B1) 40 to
95 parts by weight of vinyl cyanide compound (h) and / or alkyl (meth) acrylate (i) 10 to 90% by weight, aromatic vinyl compound (j) 10 to 90% by weight and vinyl cyanide compound (h) 5 to 60 parts by weight of a monomer mixture (B2) consisting of 0 to 20% by weight of an alkyl (meth) acrylate (i) or another vinyl compound (k) copolymerizable with the aromatic vinyl compound (j). Polymerized graft copolymer and vinyl chloride resin (C): average degree of polymerization of 400 to 100
Vinyl chloride resin that is 0. Hereinafter, the present invention will be described in detail.

The copolymer (A) used in the present invention is α
-Methylstyrene (a) 60-85% by weight, acrylonitrile (b) 15-40% by weight, and these (a),
Other vinyl compounds (c) 0 to 20 copolymerizable with (b)
A copolymer composed of 1% by weight and having a reduced viscosity of a methyl ethyl ketone soluble component in a dimethylformamide solution at 30 ° C.
In the range of 0.20 to 0.45 dl / g
1), 25 to 85% by weight of styrene (d), 15 to 40% by weight of acrylonitrile (e) and 60% by weight or less of α-methylstyrene (f), and these (d), (e),
Other vinyl compounds (g) 0 to 20 copolymerizable with (f)
A copolymer composed of 1% by weight and having a reduced viscosity of a methyl ethyl ketone soluble component in a dimethylformamide solution at 30 ° C.
In the range of 0.45 to 0.90 dl / g
2) and the weight ratio of the copolymers (A1) and (A2) is (A1) :( A2) = 20/80 to 80/20.

The copolymer (A1) of the present invention can be copolymerized with 60 to 85% by weight of α-methylstyrene (a), 15 to 40% by weight of acrylonitrile (b), and these (a) and (b). Which is a copolymer consisting of 0 to 20% by weight of another vinyl compound (c) and has a reduced viscosity of a methyl ethyl ketone soluble component of 0.2 at 30 ° C. in a dimethylformamide solution.
The copolymerizable vinyl compound (c) having a range of 0 to 0.45 dl / g includes methyl methacrylate, ethyl methacrylate, acrylic acid, methacrylic acid, ethyl acrylate, butyl acrylate, styrene, p-
Methylstyrene, chlorostyrene, phenylmaleimide, etc. are illustrated, and these are used individually or in combination of 2 or more types.

In the copolymer (A1), a particularly preferable composition is 65 to 80% by weight of α-methylstyrene (a),
20 to 35% by weight of acrylonitrile (b), and other vinyl compounds (c) copolymerizable with these (a) and (b)
A copolymer composed of 0 to 10% by weight and having a reduced viscosity of a methylethylton soluble component in a dimethylformamide solution,
It is in the range of 0.25 to 0.40 dl / g at 30 ° C. When the amount of α-methylstyrene (a) is less than 60% by weight and the amount of acrylonitrile (b) exceeds 40% by weight, heat resistance and fluidity are deteriorated, and α-methylstyrene (a) exceeds 85% by weight, acrylonitrile (b) ) Is less than 15% by weight, the polymerization characteristics are significantly deteriorated. If the reduced viscosity of the soluble component of the copolymer (A1) in the dimethylformamide solution is less than 0.20 dl / g, the impact strength will decrease, and if it exceeds 0.45 dl / g, the fluidity will decrease and the heat during molding Stability deteriorates.

The copolymer (A2) of the present invention comprises 25 to 85% by weight of styrene (d) and 15% of acrylonitrile (e).
Of 40% by weight to 60% by weight of α-methylstyrene (f), and 0 to 20% by weight of another vinyl compound (g) copolymerizable with (d), (e) and (f). The polymer and the methyl ethyl ketone soluble component have a reduced viscosity of 0.45 to 0.90 at 30 ° C. in a dimethylformamide solution.
It is in the range of dl / g. As the copolymerizable vinyl compound (g), methyl methacrylate, ethyl methacrylate, acrylic acid, methacrylic acid, ethyl acrylate,
Examples thereof include butyl acrylate, p-methylstyrene, chlorostyrene, and phenylmaleimide, and these may be used alone or in combination of two or more.

In the copolymer (A2), a particularly preferable composition is 40 to 80% by weight of styrene (d), 20 to 35% by weight of acrylonitrile (e), 45% by weight or less of α-methylstyrene (f), and these. (D), (e),
Other vinyl compound (g) 0 to 10 copolymerizable with (f)
A copolymer composed of 1% by weight and having a reduced viscosity of a methyl ethyl ketone soluble component in a dimethylformamide solution at 30 ° C.
In the range of 0.50 to 0.80 dl / g. Copolymer (A
When the composition of 2) is out of the above range, heat resistance, fluidity,
Thermal stability decreases. In the flame-retardant resin of the present invention, the copolymer (A1) and the copolymer (A2) in the copolymer (A)
The weight ratio of (A1) :( A2) = 20/80 to 80
/ 20, and preferably 25/75 to 75/25. Outside this range, the balance of heat resistance, fluidity, and thermal stability deteriorates.

The graft copolymer (B) of the present invention comprises 40 to 95 parts by weight of a rubbery polymer (B1), a vinyl cyanide compound (h) and / or an alkyl (meth) acrylate (i) of 10 to 90. % By weight, aromatic vinyl compound (j)
5 to 60 parts by weight of a monomer mixture (B2) consisting of 10 to 90% by weight and 0 to 20% by weight of another vinyl compound (k) copolymerizable with these (h), (i) and (j). It is a graft copolymer obtained by polymerization. Graft copolymer (B)
In the above, the rubber-like polymer (B1) is 40 to 95 parts by weight. If it is less than 40 parts by weight, impact resistance is lowered, and if it exceeds 95 parts by weight, fluidity is lowered. The vinyl cyanide compound (h) and / or the alkyl (meth) acrylate (i) in the monomer mixture is 10 to 90% by weight, and when the amount is less than 10% by weight, the impact resistance decreases, and when it exceeds 90% by weight. Liquidity decreases. When the aromatic vinyl compound (j) is less than 10% by weight, the fluidity decreases, and when it exceeds 90% by weight, the impact resistance decreases.

The rubber-like polymer (B1) in the graft copolymer (B) is, for example, polybutadiene rubber,
Styrene-butadiene copolymer rubber (SBR), acrylonitrile-butadiene rubber (NBR) and other diene rubbers, polybutyl acrylate and other acrylic rubbers, and ethylene-propylene-diene terpolymer rubber (EPD)
Polyolefin rubbers such as M) are exemplified, and these are used alone or in combination of two or more kinds. The vinyl cyanide compound (h) of the monomer mixture (B2) is acrylonitrile, methacrylonitrile or the like, and the alkyl (meth) arylate (i) is methyl methacrylate, ethyl methacrylate, ethyl acrylate, butyl acrylate or the like. Examples of the aromatic vinyl compound (j) include styrene, α-methylstyrene, methylstyrene, chlorostyrene and the like, and any of these may be used alone or in combination of two or more. Further, examples of the vinyl compound (k) copolymerizable with them include acrylic acid, methacrylic acid, phenylmaleimide, etc., and these may be used alone or in combination of two or more.

At the time of graft polymerization of the graft copolymer (B), a chain transfer agent of 0.1 part was added to 100 parts by weight of the monomer mixture.
When used in an amount of from 01 to 8% by weight, preferably from 0.05 to 6% by weight, the flowability and heat stability of the flame-retardant resin composition of the present invention are
Increase significantly. Examples of the chain transfer agent include n-dodecyl mercaptan, t-dodecyl mercaptan, α-methylstyrene dimer and the like, and these may be used alone or in combination of two or more kinds. When a chain transfer agent is used during graft polymerization, the graft efficiency is 1 from the viewpoint of impact strength.
It is preferably 5% or more, particularly preferably 20% or more.

The vinyl chloride resin (C) of the present invention has a degree of polymerization of 400 to 1000, preferably 500 to 800. If the degree of polymerization is less than 400, the impact strength will decrease, and if it exceeds 1000, the thermal stability will significantly decrease. The vinyl chloride resin (C) includes homopolymers and / or copolymers in which 80% by weight or more is vinyl chloride, and post-chlorinated polyvinyl chloride. The copolymer contains at least one monovinylidene compound such as ethylene, vinyl acetate, methyl methacrylate and butyl acrylate as a copolymer component in a range of 20% by weight or less.

In the flame-retardant resin of the present invention, the amount of the copolymer (A) is 25 to 85 parts by weight. If it is less than 25 parts by weight, the heat resistance is lowered, and if it exceeds 85 parts by weight, the flame retardancy is lowered.
The graft copolymer (B) is from 5 to 40 parts by weight, and if it is less than 5 parts by weight, the impact resistance will decrease, and if it exceeds 40 parts by weight, the fluidity will decrease. The vinyl chloride resin (C) is 10 to 70 parts by weight, and if it is less than 10 parts by weight, the flame retardancy is lowered, and if it exceeds 70 parts by weight, the thermal stability is lowered.

Further, in the flame-retardant resin of the present invention, 40 to 85 parts by weight of the copolymer (A) and the graft copolymer (B) are used.
In the composition of 5 to 40 parts by weight and 10 to 50 parts by weight of the vinyl chloride resin (C), from the viewpoint of thermal stability and flame retardancy,
The use of 1 to 6 parts by weight of an alkyl tin maleate polymer and 0.5 to 10 parts by weight of antimony trioxide with respect to 100 parts by weight of (A), (B) and (C) in total has a remarkable effect. In particular, the copolymer (A) and the graft copolymer (B)
When a large amount of sulfur chain transfer agent is used, its effect is remarkable. Examples of the alkyl tin maleate polymer include dibutyl tin maleate polymer, dioctyl tin maleate polymer and the like.
Used in combination of two or more species.

Copolymer (A) and graft copolymer (B)
For the polymerization of, a known polymerization initiator and a polymerization degree adjusting agent can be used, and the kind and the amount thereof are not particularly limited. After completion of the polymerization, the target powder can be obtained by solidifying by a known method. The copolymer (A) and the graft copolymer (B) may be blended in a latex state, or after coagulating each, a vinyl chloride resin, a compounding agent, etc. when producing a flame-retardant resin in a powder state. May be blended with.

As described above, according to the present invention, in the flame-retardant resin formed by mixing the special copolymer (A) with the graft copolymer (B) and the vinyl chloride resin (C), the special copolymer Copolymer (A1) and (A
A flame-retardant resin composition characterized by using the combination system of 2). The flame-retardant resin composition of the present invention is usually a well-known antioxidant, heat stabilizer, lubricant, UV absorber, pigment, antistatic agent, flame retardant, and flame retardant auxiliary as necessary. The agents may be used alone or in combination of two or more. Especially inside and outside of phenolic antioxidants, phosphite stabilizers used for styrene resins, tin stabilizers, lead stabilizers mixed with vinyl chloride resins, and various fatty acid esters, metal soaps, waxes, etc. Lubricants and the like can be used to improve the performance of the flame-retardant resin of the present invention as a molding resin. Further, the flame-retardant resin of the present invention is a vinyl chloride resin that works effectively and exhibits good flame-retardant properties. However, a flame-retardant auxiliary agent such as a halogen-based flame-retardant agent is blended and used depending on the desired flame retardancy. You can also

[0018]

EXAMPLES The present invention will now be described in more detail based on specific examples, but these examples do not limit the present invention. In the following description, “part” means part by weight and “%” means% by weight. Examples 1 to 4 and Comparative Examples 1 to 6 (a) Synthesis of copolymers (A1-1) to (A1-3) The following substances were charged in a reaction vessel equipped with a stirrer and a cooler. Water 250 parts Sodium formaldehyde sulfoxylate 0.4 parts Ferrous sulfate 0.0025 parts Disodium ethylenediaminetetraacetate 0.01 parts Sodium parimitinate 3 parts After deoxidation, after heating and stirring in a nitrogen stream at 60 ° C., The monomer mixture in the proportions shown in Table 1, the initiator cumene hydroperoxide and the polymerization degree adjusting agent tertiary decyl mercaptan were continuously added dropwise over 5 hours. After the dropping was completed, stirring was further continued at 60 ° C. for 1 hour to complete the polymerization.

(B) Copolymers (A2-1) to (A2-
Production of 4) The following substances were charged in a reaction vessel equipped with a stirrer and a cooler. Water 250 parts Sodium formaldehyde sulfoxylate 0.4 parts Ferrous sulfate 0.0025 parts Disodium ethylenediaminetetraacetate 0.01 parts Sodium parimitinate 3 parts After deoxidation, after heating and stirring in a nitrogen stream at 60 ° C., The monomer mixture in the proportions shown in Table 1, the initiator cumene hydroperoxide and the polymerization degree adjusting agent tertiary decyl mercaptan were continuously added dropwise over 5 hours. After the dropping was completed, stirring was further continued at 60 ° C. for 1 hour to complete the polymerization.

[0020]

[Table 1]

(C) Graft copolymers (B1) to (B
Production of 3) The following substances and the rubber-like polymer shown in Table 2 were charged into a reaction vessel equipped with a stirrer and a cooler. Water 250 parts Sodium formaldehyde sulfoxylate 0.2 parts Ferrous sulfate 0.0025 parts Disodium ethylenediaminetetraacetate 0.01 parts Rubber-like polymer Predetermined amount shown in Table 2 After deoxidation, 60 ° C in nitrogen stream After heating and stirring, the monomer mixture, the initiator cumene hydroperoxide, and the chain transfer agent, tertiary decyl mercaptan, in the proportions shown in Table 2 were continuously added dropwise over 5 hours. After the dropping was completed, stirring was further continued at 60 ° C. for 1 hour to complete the polymerization.

[0022]

[Table 2]

The resulting copolymers (A1-1) to (A1-
3), the copolymers (A2-1) to (A2-4) and the graft copolymers (B1) to (B3) are mixed in the proportions shown in Table 3, and a phenol-based antioxidant is added, followed by chlorination. After coagulation with an aqueous calcium solution, washing with water, dehydration, and drying, copolymers (A1), (A2), and graft copolymer (B)
A mixed powder of

(D) Method for producing flame-retardant resin Copolymers (A1-1) to (A1-3), (A2-1) to (A) produced as described in (a), (b) and (c) above. (A2-
4), graft copolymers (B1) to (B3), vinyl chloride resins (C1) and (C2), and 4 parts of dibutyltin maleate polymer, 3 parts of antimony trioxide, 1 part of polyethylene wax, glycerin tristea. 1 part of the rate was blended with a super mixer, and pellets were produced with a 40 m / m extruder. A test piece was molded from the pellet with a 5 ounce injection molding machine under the conditions of a screw rotation speed of 80 rpm and a nozzle set temperature of 200 ° C.

Various physical properties were evaluated using the test pieces obtained in Examples 1 to 4 and Comparative Examples 1 to 6. The results are shown in Table 3. The measurement and evaluation methods of physical properties are as follows.
Heat resistance is based on the ASTM (D-256) standard.
It was evaluated at a heat distortion temperature of 6 kg / cm ² load. The fluidity was evaluated by the flow length in a mosquito coil incense-shaped mold (thickness 3 mm) at a set temperature of 190 ° C. and an injection pressure of 1100 kg / cm ² . Thermal stability is set to 200 on 5 oz injection molding machine
After 20 minutes of residence at 0 ° C., the burns were visually observed and evaluated by 5 grades. The smaller the number, the more marked the discoloration. The flame retardancy was evaluated at a thickness of 1/16 inch based on UL-94 standard.

The abbreviations and symbols in Tables 1 to 3 are as follows. (Vinyl chloride resin) C1: Polyvinyl chloride, degree of polymerization 600 C2: Polyvinyl chloride, degree of polymerization 1200 (rubber-like polymer) ... Used in latex state PBD: Polybutadiene rubber, average particle size 2500Å (monomer Etc.) AN: Acrylonitrile BA: Butyl acrylate MMA: Methyl methacrylate St: Styrene αSt: α-Methylstyrene tDM: Tertiary decyl mercaptan CHP: Cumene hydroperoxide

[0027]

[Table 3]

[0028]

As described above, the flame-retardant resin composition of the present invention has high heat resistance and excellent fluidity and thermal stability during molding.

Claims (4)

[Claims] 1. 25 to 85 parts by weight of the following copolymer (A), 5 to 40 parts by weight of a graft copolymer (B), and 10 to 70 parts by weight of a vinyl chloride resin (C) [however, A) +
Flame-retardant resin composition consisting of (B) + (C) = 100 parts by weight]: Copolymer (A): α-methylstyrene (a) 60 to 85
% By weight, 15-40% by weight of acrylonitrile (b), and 0-20 other vinyl compounds (c) copolymerizable with α-methylstyrene (a) or acrylonitrile (b).
A copolymer composed of 1% by weight and having a reduced viscosity of a methyl ethyl ketone soluble component in a dimethylformamide solution at 30 ° C.
In the range of 0.20 to 0.45 dl / g
1) and styrene (d) 25 to 85% by weight, acrylonitrile (e) 15 to 40% by weight, α-methylstyrene (f) 6
A copolymer of 0% by weight or less and 0 to 20% by weight of another vinyl compound (g) copolymerizable with styrene (d), acrylonitrile (e) or α-methylstyrene (f) and soluble in methyl ethyl ketone. Has a reduced viscosity of 0.45 to 0.90 dl at 30 ° C. in a dimethylformamide solution.
/ g in the range of the copolymer (A2), the weight ratio of the copolymer (A1) and (A2) is (A1) :( A2)
= 20/80 to 80/20, graft copolymer (B): rubbery polymer (B1) 40 to
95 parts by weight of vinyl cyanide compound (h) and / or alkyl (meth) acrylate (i) 10 to 90% by weight, aromatic vinyl compound (j) 10 to 90% by weight and vinyl cyanide compound (h) 5 to 60 parts by weight of a monomer mixture (B2) consisting of 0 to 20% by weight of an alkyl (meth) acrylate (i) or another vinyl compound (k) copolymerizable with the aromatic vinyl compound (j). Polymerized graft copolymer and vinyl chloride resin (C): average degree of polymerization of 400 to 100
Vinyl chloride resin that is 0. 2. The process according to claim 1, wherein the chain transfer agent is used in an amount of 0.01 to 8 parts by weight per 100 parts by weight of the monomer mixture (B2) during the graft polymerization of the graft copolymer (B). Flammable resin composition. 3. The flame-retardant resin composition according to claim 1, wherein the graft efficiency of the graft copolymer (B) during the graft polymerization is 15% by weight or more. 4. A total of 100 parts by weight of 40 to 85 parts by weight of the copolymer (A), 5 to 40 parts by weight of the graft copolymer (B), and 10 to 70 parts by weight of the vinyl chloride resin (C), The flame-retardant resin composition according to claim 1, which comprises 1 to 6 parts by weight of an alkyl tin maleate polymer and 0.5 to 10 parts by weight of antimony trioxide.