JP2725053B2 - Heat resistant ABS resin composition - Google Patents

Description

The present invention relates to an improved heat-resistant ABS resin composition and, more particularly, to a maleimide or α-methylstyrene-modified ABS resin and a specific organic cyclic phosphite compound. An improved heat-resistant ABS resin composition comprising:

[Conventional technology and its problems]

Maleimide or α-methylstyrene-modified ABS resin has a good balance of heat resistance, impact resistance and fluidity, and can be molded and processed in the same way as ABS resin. Because it has features not found in resins and engineering plastics, it is expected to be used in a wide range of applications, such as automotive parts, electrical industrial parts, and office machines.

However, as the ratio of the maleimide compound increases, the heat resistance of the maleimide-modified ABS resin increases, but the compatibility between the maleimide-containing copolymer and the graft copolymer deteriorates. There is a disadvantage that excellent properties as a reinforced resin are impaired. Also, α-
Since the methylstyrene-modified ABS resin is obtained by copolymerizing α-methylstyrene, it is liable to be thermally decomposed by depolymerization, resulting in poor moldability or brittleness.

In addition, due to the introduction of the maleimide or α-methylstyrene component, when processing, because the fluidity in the mold decreases, when manufacturing large molded parts, the processing temperature is higher than the conventional ABS resin , 260 ° C or higher. For this reason, the thermal oxidation deterioration of the resin becomes remarkable, and silver streaks (or flashes) are generated on the surface of the molded product, and the appearance of the product is impaired.

In order to improve this, for example, 1,3,5-tris (3,5-
Di-tert-butyl-4-hydroxybenzyl) isocyanurate (JP-A-62-45643) or 3-tert-butyl-
Phenol compounds such as 4-hydroxy-5-methylphenylpropionic acid ester (JP-A-62-181352 and JP-A-62-220544) or bis (2,6-di-tert-butyl-4-alkylphenyl) ) A pentaerythritol diphosphite compound (Japanese Patent Application Laid-Open No. 63-254157) has been proposed, and although some improvement has been recognized, it has not been sufficient yet, and further improvement has been desired.

[Means for solving the problem]

The present inventors have conducted intensive studies in view of the present situation, and found that maleimide-modified or α-methylstyrene-modified ABS
It has been found that by adding a specific organic cyclic phosphite compound to a resin, not only heat resistance and weather resistance are excellent but also processability is remarkably improved, and the present invention has been completed.

That is, the present invention comprises adding 0.001 to 5 parts by weight of an organic cyclic phosphite compound represented by the following general formula (I) to 100 parts by weight of a maleimide or α-methylstyrene-modified ABS resin. General formula (II), (III)
Heat-resistant ABS not containing phenolic antioxidants and hindered amine compounds represented by (IV) and (IV)
The present invention provides a resin composition.

(Wherein, R ₁ represents a tertiary butyl group or a tertiary amyl group,
R ₂ represents an alkyl group having 1 to 9 carbon atoms, R ₃ represents a hydrogen atom or an alkyl group having 1 to ₄ carbon atoms, and R ₄ represents an alkyl group having 1 to 30 carbon atoms. ) (In the formula, Ar is a formula in both formulas (II) and (III). Wherein R ₅ and R ₇ represent an alkyl group having 1 to 4 carbon atoms, R ₆ represents a 1 to 4 valent alcohol residue, and n represents 1 to 4
And R ₈ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. In the above formula, 1 to 9 carbon atoms represented by R _2.
Examples of the alkyl group include methyl, ethyl, propyl, isopropyl, butyl, secondary butyl, tertiary butyl, isobutyl, amyl, tertiary amyl, hexyl, heptyl, octyl, isooctyl, 2-ethylhexyl, tertiary octyl, nonyl, Tertiary nonyl and the like, examples of the alkyl group having 1 to 4 carbon atoms represented by R ₃ and R ₅ include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, isobutyl and the like. Examples of the alkyl group having 1 to 30 carbon atoms represented by R ₄ include methyl,
Ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, isobutyl, amyl, tert-amyl, hexyl, heptyl, octyl, isooctyl, 2-ethylhexyl, tert-octyl, nonyl, tertiary nonyl, decyl, isodecyl, Dodecyl, tetradecyl, hexadecyl, octadecyl, eicosyl, docosyl, tetracosyl, triacontyl and the like can be mentioned.

Next, typical examples of the organic cyclic phosphite compound represented by the above general formula (I) used in the present invention include the compounds shown in Table 1 below.

The organic cyclic phosphite compound represented by the general formula (I) used in the present invention includes, for example, phosphorus trichloride and 2,2 ′
An alkylidenebisphenol is reacted to produce a compound in which R ₄ —O— in the above formula (I) is a chlorine atom, and is easily produced by reacting the compound with an alcohol represented by R ₄ —OH. can do.

Next, specific synthesis examples of the organic cyclic phosphite compound used in the present invention will be described.

Synthesis Example 2,2'-methylenebis (4,6-di-tert-butylphenyl)-
Synthesis of stearyl phosphite (No. 4 compound) In a 500 ml four-necked flask, 42.5 g of 2,2'-methylenebis (4,6-di-tert-butylphenol) and 100 g of toluene
And 0.86 g of triethylamine were charged, and 16.5 g of phosphorus trichloride was added dropwise at 60 to 65 ° C. while stirring. After completion of the dropwise addition, the temperature was gradually increased under a nitrogen stream, and the mixture was stirred under reflux for 2 hours.

Excess phosphorous trichloride is distilled off under reduced pressure, and after cooling to 60 ° C., 12.1 g of triethylamine and 27 g of stearyl alcohol
Was added and stirred at 80 ° C. for 4 hours. After cooling, the produced triethylamine hydrochloride was filtered off, and the solvent was distilled off.

The residue was crystallized from methanol to give a white powder product having a melting point of 65 ° C.

IR (cm ^-1 ) 2925, 2850: methylene, 1230, 1200: tert-butyl, 1100: -O-phenyl, 1020: PO-alkyl, 840: PO-phenyl H ¹ -NMR (in CDCl ₃ , 60 MHz, TMS standard) δ value; 0.8: 3H, t, methyl group (terminal of stearyl group) 1.2 to 1.3: 73H, sss, tert-butyl group and stearyl group 3.2 to 4.4: 4H, dd, methylene group and- _{O-CH 2 - 7.2: 4H} , s, relative amount of the synthetic resin 100 parts by weight of the aromatic hydrogens of these organic cyclic phosphite compound is 0.001 to 5 parts by weight.

The method of adding the organic cyclic phosphite compound represented by the general formula (I) of the present invention to a heat-resistant ABS resin is not particularly limited, and a generally used method can be applied as it is.

For example, a method of dry blending an additive powder with a resin powder or a pellet, a method of spraying a solution or a melt of an additive on a resin powder or a pellet, a method of mixing a dispersion of an additive with a resin latex, and then salting out. A method or the like can be used.

Examples of the heat-resistant ABS resin in the present invention include, for example, an aromatic vinyl monomer, a copolymer obtained by mixing a maleimide compound with a vinyl cyan monomer, and an aromatic vinyl monomer in the presence of a conjugated diolefin rubber. A resin composition comprising a graft copolymer obtained by copolymerizing a vinylcyan monomer, a resin composition in which a maleimide compound is added to a graft of the graft copolymer, and a conjugated diolefin rubber. A graft copolymer obtained by copolymerizing an aromatic vinyl monomer, a vinyl cyan monomer and a maleimide compound, an ABS resin obtained by graft-polymerizing styrene and acrylonitrile to a diene polymer, and α-methylstyrene. Acrylonitrile copolymer, α-methylstyrene / acrylonitrile / styrene copolymer, α-methylstyrene / acrylonitrile A method of blending a 2,5-dichlorostyrene copolymer or an α-methylstyrene-acrylonitrile-methyl methacrylate copolymer, grafting styrene and acrylonitrile to a diene rubber latex, and then grafting α-methylstyrene and acrylonitrile , A method in which a part of styrene is replaced with α-methylstyrene in an NBR / AS blend, or a method obtained by blending a butadiene / acrylonitrile / styrene copolymer with an α-methylstyrene / acrylonitrile copolymer And has a high heat distortion temperature.

In addition, these heat-resistant ABS resin, for example, polycarbonate resin, saturated polyester resin, polyamide resin,
When used in combination with an engineering resin such as a polyphenylene ether resin or a boria acetal resin, one of the drawbacks of these engineering resins is a low notch impact strength.

The composition of the present invention may be further added with a sulfur-based antioxidant to improve its oxidative stability. Examples of the sulfur-based antioxidants include dialkylthiodipropionates such as dilauryl, dimyristyl and distearyl esters of thiodipropionic acid and β-alkyl of polyols such as pentaerythritol tetra (β-dodecylmercaptopropionate). And mercaptopropionates.

The light resistance can be further improved by adding an ultraviolet absorber to the composition of the present invention.

Examples of the light stabilizer include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, and 5,5'-methylenebis (2-hydroxy-4-methoxybenzophenone). 2-hydroxybenzophenones; 2- (2'-hydroxy-5'-methylphenyl)
Benzotriazole, 2- (2'-hydroxy-5'-
Tert-octylphenyl) benzotriazole, 2-
(2'-hydroxy-3 ', 5'-di-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-
3 ', 5'-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- ( 2- (2'-hydroxyphenyl) such as 2'-hydroxy-3 ', 5'-dicumylphenyl) benzotriazole and 2,2'-methylenebis (4-tert-octyl-6-benzotriazolyl) phenol Benzotriazoles; phenyl salicylate, resorcinol monobenzoate, 2,4-ditert-butylphenyl-3 ',
5'-di-tert-butyl-4'-hydroxybenzoate,
Benzoates such as hexadecyl-3,5-ditert-butyl-4-hydroxybenzoate; substituted oxanilides such as 2-ethyl-2'-ethoxyoxanilide and 2-ethoxy-4'-dodecyloxanilide; ethyl Cyanoacrylates such as -α-cyano-β, β-diphenylacrylate and methyl-2-cyano-3-methyl-3- (p-methoxyphenyl) acrylate;

Other if necessary, the composition of the present invention contains a heavy metal deactivator, nucleating agent, metal soap, pigment, filler, organotin compound, plasticizer, epoxy compound, foaming agent, antistatic agent,
Flame retardants, lubricants, processing aids and the like can be included.

〔Example〕

Next, the present invention will be specifically described with reference to examples. However, the invention is not limited by these examples.

Example 1 (Blending) N-phenylmaleimide-modified ABS resin (heat deformation temperature 130
° C) 100 parts by weight Organic phosphite (Table 1) 0.3 After dry blending the above composition, it was dried at 80 ° C for 6 hours. Next, cylinder temperature 250 ° C, rotation speed 200rpm
The pellets were prepared using a twin screw extruder (L / D = 30, vent up 40 mmHg). The pellet was dried again at 80 ° C. for 6 hours. Using these pellets, injection molding machine (1 oz., Cylinder temperature 280 ℃ and 300 ℃, nozzle temperature 300
℃, mold 60 × 36 × 2 mm, mold temperature 60 ° C., injection 10 seconds, cooling 3 seconds cycle) to make a test piece of 2 mm thickness. Silver streaks on the surface of the test piece were observed. Note that the generation state of silver streaks is displayed in 10 stages, and indicates 1 (none) ← → 10 (large). At the same time, the yellowness of the test piece was measured using a Hunter colorimeter, and the color difference ΔE from the yellowness after staying at 280 ° C for 5 minutes at 300 ° C was measured. The results are shown in Table-2. Was.

Example 2 (Formulation) α-methylstyrene-modified ABS resin (α-methylstyrene content 40%) (heat deformation temperature 120 ° C) 100 parts by weight Organic phosphite (Table-1) 0.3 Same as Example 1 with the above composition And the results are shown in Table 3.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-238034 (JP, A) JP-A-2-233735 (JP, A) JP-A-2-80438 (JP, A) JP-A-1- 254769 (JP, A)

Claims (1)

(57) [Claims] (1) A maleimide or α-methylstyrene modification
An organic phosphite compound represented by the following general formula (I) is added in an amount of 0.001 to 5 parts by weight based on 100 parts by weight of the ABS resin, provided that the following general formulas (II), (III) and (IV) )
A stabilized heat-resistant ABS resin composition not containing a phenolic antioxidant and a hindered amine compound represented by the formula: (Wherein, R ₁ represents a tertiary butyl group or a tertiary amyl group,
R ₂ represents an alkyl group having 1 to 9 carbon atoms, R ₃ represents a hydrogen atom or an alkyl group having 1 to ₄ carbon atoms, and R ₄ represents an alkyl group having 1 to 30 carbon atoms. ) (In the formula, Ar is a formula in both formulas (II) and (III). Wherein R ₅ and R ₇ represent an alkyl group having 1 to 4 carbon atoms, R ₆ represents a 1 to 4 valent alcohol residue, and n represents 1 to 4
And R ₈ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. )