JPH04304269A - Stabilized thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To obtain a thermoplastic resin composition excellent in thermal processing stability and thermal discoloration resistance during high-temperature molding by mixing a thermoplastic resin with a specified diphenylphosphine compound. CONSTITUTION:A resin composition prepared by mixing a thermoplastic resin with a diphenylphosphine compound of formula I. The diphenylphosphine compound can be produced, for example, by reacting diphenylphosphine with an unsaturated carboxylic acid ester of formula II by heating in a solvent such as tetrahydrofuran. Examples of the unsaturated carboxylic acid esters include acrylic, methacrylic and crotonic esters. The diphenylphosphine compound is added desirably in a amount of 0.01-2 pts.wt. per 100 pts.wt. thermoplastic resin.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a stabilized thermoplastic resin composition, and more particularly to a thermoplastic resin composition that has excellent heat processing stability and heat discoloration resistance during high temperature molding. . The present invention also relates to a stabilizer for resins that is effective in stabilizing such thermoplastic resins.

0002

[Prior Art] Various thermoplastic resins, including polyolefins such as polyethylene and polypropylene, have excellent physical, chemical, and electrical properties, and are therefore processed by various methods. It is used in many fields as molded products, sheets, films, fibers, etc. However, thermoplastic resins suffer from problems such as softening, embrittlement, surface cracks, or discoloration due to thermal deterioration during molding, resulting in a significant decrease in commercial value. Particularly recently, there has been a trend toward molding at higher temperatures for the purpose of improving productivity, and it has become more necessary than ever to prevent thermal deterioration during high-temperature molding processing.

Conventionally, in order to prevent thermal deterioration during these molding processes, hindered phenol compounds such as 2,6-di-t-butyl-4-methylphenol and tris(2,
Organic phosphite compounds such as (4-di-t-butylphenyl) phosphite have been used alone or in various combinations.

0004

[Problem to be solved by the invention] Although thermal deterioration during molding processing can be considerably suppressed by blending these phenol-based and phosphite-based compounds, the effect when molding at higher temperatures is still insufficient. There was a need for an even better heat-resistant processing stabilizer.

Therefore, the present inventors have developed a stabilizer that can improve these inadequacies of the prior art, that is, a stabilizer that can improve the heat-resistant processing stability of thermoplastic resins and that can improve the thermal processing stability of thermoplastic resins by hot processing. The present invention was achieved as a result of extensive research aimed at developing a stabilizer that can also suppress coloration and obtaining a highly stabilized thermoplastic resin composition by incorporating such a stabilizer.

[0006]

[Means for Solving the Problems] The present invention provides a thermoplastic resin having the following general formula (I).

[0007]

[Chemical 3]

(In the formula, R1 and R2 each independently represent hydrogen or methyl, and R3 has a carbon number of 1 to 18
Provided is a thermoplastic resin composition containing a diphenylphosphine compound represented by the following alkyl group. By blending such a specific diphenylphosphine compound, it is possible to obtain a thermoplastic resin composition that has excellent heat-resistant processing stability and heat-resistant discoloration during high-temperature molding.

Accordingly, the present invention also provides a resin stabilizer containing a diphenylphosphine compound represented by the general formula (I) as an active ingredient, which is useful for stabilizing thermoplastic resins during hot processing.

In the general formula (I), the alkyl group represented by R3 has 1 to 18 carbon atoms, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, decyl, dodecyl, tetradecyl, Examples include hexadecyl and octadecyl. The alkyl group having 3 or more carbon atoms may be linear or branched.

The diphenylphosphine compound represented by the general formula (I) is, for example, diphenylphosphine and the following general formula (II).

0012

[C4]

It can be produced by heating and reacting an unsaturated carboxylic acid ester represented by the formula (wherein R1, R2 and R3 have the same meanings as above) in a solvent such as tetrahydrofuran. General formula (
Examples of the unsaturated carboxylic ester II) include acrylic esters, methacrylic esters, and crotonic esters.

The stabilizer according to the present invention containing the diphenylphosphine compound represented by the general formula (I) as an active ingredient may be each compound alone, or may be a mixture of multiple compounds, or may be a mixture of a plurality of compounds. may be a mixture with other components. Examples of mixtures with other components include a diphenylphosphine compound of general formula (I) supported on a carrier that does not affect the physical properties of the resin, a masterbatch in which this diphenylphosphine compound is supported on a resin, and a mixture of this diphenylphosphine compound and the following. Examples include mixtures with various additives.

In the present invention, the diphenylphosphine compound represented by the general formula (I) is preferably blended in an amount of 0.01 to 2 parts by weight per 100 parts by weight of the thermoplastic resin. If the amount of the diphenylphosphine compound is less than 0.01 part by weight, the effect of improving heat-resistant processing stability and heat-resistant discoloration is not necessarily sufficient, and even if the amount exceeds 2 parts by weight, the effect may not be commensurate with that. Since no improvement can be expected, it is economically disadvantageous.

Thermoplastic resins that can be stabilized according to the present invention are generally various polymers exhibiting thermoplasticity, and include, for example, the following. (1) Polyethylene, such as high-density polyethylene (
HD-PE), low density polyethylene (LD-PE), linear low density polyethylene (L-LDPE), (2)
Polypropylene, (3) Methylpentene polymer, (4) EEA (ethylene/ethyl acrylate copolymer) resin, (5) Ethylene/vinyl acetate copolymer, (6)
Ionomer resin, (7) polystyrene, poly(p-methylstyrene)
, poly(α-methylstyrene), (8) AS (acrylonitrile/styrene copolymerization)
Resin, (9) ABS (acrylonitrile/butadiene/styrene copolymer) resin, (10) AAS (special acrylic rubber/acrylonitrile/styrene copolymer) resin, (11) ACS (acrylonitrile/chlorinated polyethylene/styrene copolymer) resin , (12) Chlorinated polyethylene, polychloroprene,
Chlorinated rubber, (13) Polyvinyl chloride, polyvinylidene chloride, (
14) Methacrylic resin, (15) Ethylene/vinyl alcohol copolymer resin,
(16) Fluororesin, (17) Polyacetal, (18) Grafted polyphenylene ether resin and polyphenylene sulfide resin, (19) Polyurethane, (20) Polyamide, (21) Polyethylene terephthalate, polybutylene terephthalate, (22) Polycarbonate, ( 23) polyarylate, (24) polysulfone, polyetheretherketone, polyethersulfone, (25) aromatic polyester resin.

Among these various thermoplastic resins, polyolefins such as polyethylene and polypropylene are preferably used, and the effects of incorporating the diphenylphosphine compound of the general formula (I) are noticeable. Among polyolefins, polypropylene is particularly preferably used.

[0018] In the composition of the present invention, if necessary,
In addition to the diphenylphosphine compound of general formula (I), other additives such as phenolic antioxidants, sulfur antioxidants, phosphorus antioxidants, ultraviolet absorbers, hindered amine light stabilizers, lubricants, and plasticizers , flame retardant, nucleating agent,
One or more types of metal deactivators, antistatic agents, pigments, inorganic fillers, etc. may be blended. Specific examples of these additives include the following.

[0019] As the phenolic antioxidant, 2,6
-di-butyl-4-methylphenol, pentaerythrityl tetrakis[3-(3,5-di-t-butyl-
4-hydroxyphenyl)propionate], octadecyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, triethylene glycol bis[3-(3-t-butyl-4-hydroxy-5
-methylphenyl)propionate], 3,9-bis[
2-{3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy}-1,1-dimethylethyl]-2,4,8,10-tetraoxaspiro[
5.5] Undecane, tris(3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate, 1
,3,5-trimethyl-2,4,6-tris(3,5-
di-t-butyl-4-hydroxybenzyl)benzene,
2,4-bis(n-octylthio)-6-(3,5-di-t-butyl-4-hydroxyanilino)-1,3,5
-triazine, 1,6-hexanediol bis[3
-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,2'-thiodiethylene bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], Tris(4-t-butyl-
3-hydroxy-2,6-dimethylbenzyl) isocyanurate, 2-[1-(2-hydroxy-3,5-
di-t-pentylphenyl)ethyl]-4,6-di-t
-pentylphenyl acrylate, 2-t-butyl-6-(3-t-butyl-5-methyl-2-hydroxybenzyl)-4-methylphenyl acrylate, and the like.

Examples of sulfur-based antioxidants include dilauryl 3,3'-thiodipropionate and dimyristyl.
3,3'-thiodipropionate, distearyl
Examples include 3,3'-thiodipropionate and pentaerythrityl tetrakis (3-laurylthiopropionate).

Examples of phosphorus antioxidants include tris(nonylphenyl) phosphite and tris(2,4-di-
t-butylphenyl) phosphite, tetrakis(
2,4-di-t-butylphenyl) 4,4'-biphenylene diphosphonite, bis(2,4-di-t-butylphenyl) Pentaerythritol Diphosphite, distearyl Pentaerythritol Diphosphite, bis(2,6- di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, 2,2'-methylenebis(4,6-di-t-butylphenyl) octyl phosphite, 2,2'-ethylidenebis(4,6 -di-t-butylphenyl)fluorophosphonite and the like.

As the ultraviolet absorber, 2-hydroxy-
4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2,2'-dihydroxy-4
-methoxybenzophenone, bis(5-benzoyl-4
-hydroxy-2-methoxyphenyl)methane, 2,2
',4,4'-tetrahydroxybenzophenone, 2-
(2-hydroxy-5-methylphenyl)benzotriazole, 2-[2-hydroxy-3-(3,4,5,6
-tetrahydrophthalimidomethyl)-5-methylphenyl]benzotriazole, 2-(3-t-butyl-2
-hydroxy-5-methylphenyl)-5-chlorobenzotriazole, 2-(3,5-di-t-butyl-2-
hydroxyphenyl)benzotriazole, 2-(2-
Hydroxy-5-t-octylphenyl)benzotriazole, 2-(2-hydroxy-3,5-di-t-pentylphenyl)benzotriazole, 2-[2-hydroxy-3,5-bis(α,α- dimethylbenzyl)phenyl]-2H-benzotriazole, 2-(3,5-di-t-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole, 2,2'-methylenebis[6-(
2H-benzotriazol-2-yl)-4-(1,1
,3,3-tetramethylbutyl)phenol], poly(
3-11) (ethylene glycol) and methyl 3
-[3-(2H-benzotriazol-2-yl)-5
-Condensation product with t-butyl-4-hydroxyphenyl]propionate, octyl 3-[3-t-butyl-5
-(5-chloro-2H-benzotriazol-2-yl)-4-hydroxyphenyl]propionate and the like.

As the hindered amine light stabilizer, bis(2,2,6,6-tetramethyl-4-piperidyl)
Sebacate, dimethyl succinate and 1-
(2-hydroxyethyl)-4-hydroxy-2,2,
Polycondensate with 6,6-tetramethylpiperidine, poly[
(6-morpholino-1,3,5-triazine-2,4-
diyl) {(2,2,6,6-tetramethyl-4-piperidyl)imino}hexamethylene {(2,2,6,6-
tetramethyl-4-piperidyl)imino], bis(1
,2,2,6,6-pentamethyl-4-piperidyl)
2-(3,5-di-t-butyl-4-hydroxybenzyl)-2-butylmalonate, 4-[3-(3,5-
di-t-butyl-4-hydroxyphenyl)propionyloxy]-1-[2-{3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxy}ethyl]-2,2,6 , 6-tetramethylpiperidine, bis(1,2,2,6,6-pentamethyl-4-piperidyl) decanedioate, tetrakis(2,2,6,
6-tetramethyl-4-piperidyl) 1,2,3,
4-Butanetetracarboxylate, poly[{6-(1
,1,3,3-tetramethylbutyl)imino-1,3,
5-triazine-2,4-diyl} {(2,2,6,6
-tetramethyl-4-piperidyl)imino}hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl)imino}], 1,2,3,4-butanetetracarboxylic acid and 1,2, Mixed esterified product of 2,6,6-pentamethyl-4-piperidinol and 1-tridecanol, 1,2,3,4-butanetetracarboxylic acid
1,2,2,6,6-pentamethyl-4-piperidinol and 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro[5.5] Mixed esterified product with undecane, 1,2
,3,4-butanetetracarboxylic acid and 2,2,6,
6-tetramethyl-4-piperidinol and 3,9-
Bis(2-hydroxy-1,1-dimethylethyl)-2
, 4,8,10-tetraoxaspiro[5,5]undecane mixed ester, N,N'-bis(2,2,
Polycondensate of 6,6-tetramethyl-4-piperidyl)hexamethylenediamine and 1,2-dibromoethane, 2-methyl-2-(2,2,6,6-tetramethyl-
4-piperidyl)amino-N-(2,2,6,6-tetramethyl-4-piperidyl)propionamide, bis(
1-acryloyl-2,2,6,6-tetramethyl-4
-piperidyl)2,2-bis(3,5-di-t-butyl-4-hydroxybenzyl)malonate, N,N',4
,7-tetrakis[4,6-bis{N-butyl-(1,
2,2,6,6-pentamethyl-4-piperidyl)amino}-1,3,5-triazin-2-yl]-4,7-
Diazadecane-1,10-diamine, bis(2,2,6
, 6-tetramethyl-4-piperidyl) succinate, 2,2,6,6-tetramethyl-4-piperidyl
methacrylate, 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate, tetrakis(1,2
,2,6,6-pentamethyl-4-piperidyl) 1
, 2,3,4-butanetetracarboxylate and the like.

In the present invention, the thermoplastic resin has the general formula (
As a method for blending the diphenylphosphine compound (I), any method suitable for obtaining a homogeneous mixture can be adopted. For example, kneading can be performed using a roll, a Banbury mixer, a single screw extruder, a twin screw extruder, or the like. When blending the other additives mentioned above, they can be added by any of these methods. The kneaded composition is molded by any method such as injection molding, extrusion molding, or compression molding.

[0025]

EXAMPLES The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited thereto. Note that "parts" in the examples are parts by weight unless otherwise specified.

Reference example: 2-butoxycarbonylethyl diphenylphosphine (compound 1) and 2-
Synthesis of octadecyloxycarbonylethyl diphenylphosphine (compound 2) 10 g of diphenylphosphine, 6.88 g of acrylic acid n-butyl ester, and 100 g of anhydrous tetrahydrofuran were placed in a reactor equipped with a reflux condenser, a thermometer, and a stirrer. The mixture was heated to 50° C. under a nitrogen stream and stirred at this temperature for 24 hours while maintaining the nitrogen atmosphere. After that, tetrahydrofuran was distilled off and the residue was purified by silica gel column chromatography, and a colorless oil of 2-butoxycarbonylethyl diphenylphosphine was obtained.
．． 2g was obtained. m/z=314. 2-octadecyloxycarbonylethyl diphenylphosphine was produced according to the above method except for changing the raw materials.

[0027]

[0028] The symbols of the test compounds in Table 1 have the following meanings. Compound 1: 2-butoxycarbonylethyl diphenylphosphine Compound 2: 2-octadecyloxycarbonylethyl diphenylphosphine AO-1: 2,6-di-t-butyl-4-methylphenol AO-2: Pentaerythrityl tetrakis[3
-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] AO-3: Tris(2,4-di-t-butylphenyl) phosphite

Heat-resistant processing stability test: Using a 30 mmφ single screw extruder, the above blend was melt-kneaded at 200° C. and pelletized. The obtained pellets were placed in a melt indexer and heated to 280°C according to JIS K 7210.
The fluidity after residence for 5 minutes and the fluidity after residence for 30 minutes (MI value: g/10 minutes) were measured to evaluate the heat-resistant processing stability. The smaller the difference between the fluidity after staying for 5 minutes and the fluidity after staying for 30 minutes, the better the heat-resistant processing stability at high temperatures is. The results are shown in Table-1.

Test for heat resistance and discoloration: Using a 30 mm diameter single screw extruder, the above formulation was extruded three times at 280°C. The resulting pellets were molded into 60x40x1 mm flat plates using a 5.5 oz injection molding machine at 200°C. The YI value (yellowness index) of this flat plate was measured. The smaller the value of YI, the better the heat resistance and discoloration, that is, the less likely it is to discolor. Display the results -
Shown in 1.

[0031]

[0032]

Effects of the Invention The thermoplastic resin composition of the present invention has excellent heat-resistant processing stability during high-temperature molding and heat-resistant discoloration. Therefore, it is possible to increase the molding temperature of thermoplastic resin to increase productivity, and it is also useful in fields where it is used at high temperatures, so its industrial value is extremely high. Therefore, the resin stabilizer containing the diphenylphosphine compound of general formula (I) as an active ingredient used in the formulation of this thermoplastic resin composition is also excellent in improving heat-resistant processing stability and heat-resistant discoloration of the thermoplastic resin. This shows the effect of

Claims (3)

[Claims] Claim 1: A thermoplastic resin containing diphenyl represented by the following general formula [Formula 1] (wherein R1 and R2 each independently represent hydrogen or methyl, and R3 represents an alkyl group having 1 to 18 carbon atoms). A stabilized thermoplastic resin composition comprising a phosphine compound. 2. The composition according to claim 1, wherein the thermoplastic resin is a polyolefin. 3. A diphenylphosphine compound represented by the following general formula [Formula 2] (wherein R1 and R2 each independently represent hydrogen or methyl, and R3 represents an alkyl group having 1 to 18 carbon atoms) as an active ingredient. Stabilizer for resins.