JPH0480059B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a novel stabilizer that is incorporated into an olefin polymer to suppress thermal oxidative deterioration and photo-induced deterioration of the resin. Processed products of this olefin polymer are useful as beer crates, agricultural films, automobile exterior parts, and hollow containers. [Prior art] In general, synthetic resins such as polyethylene, polypropylene, polyvinyl chloride, and ABS suffer from thermal deterioration or oxidation during molding, or deterioration of weather resistance mainly due to ultraviolet rays and oxygen even after they are made into products. It is known that this causes color changes, decreases in mechanical strength, etc., and that it cannot withstand long-term use. In order to eliminate such drawbacks, it is necessary to add one or more types of heat stabilizers or light stabilizers to the synthetic resin to suppress various types of deterioration. Such heat stabilizers generally include tetrakis[methylene-
Phenolic antioxidants such as 3-(3,5-di-t-butyl-4-hydroxyphenyl)-propionate]methane (trade name, RA-1010, manufactured by Ciba Gaiki Co., Ltd.) are mainly used. As light stabilizers, hindered amine compounds such as bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (trade name, Sanol LS770, manufactured by Sankyo Co., Ltd.) are generally known. However, the drawback is that there is an antagonistic effect between certain heat and light stabilizers. That is,
For the purpose of improving both the heat aging resistance and weather resistance of synthetic resins, for example, when RA-1010 as a heat stabilizer and Sanol LS770 as a light stabilizer are added together to a synthetic resin, each of them may be added individually. It is known that the heat aging resistance is significantly reduced compared to the conventional case. [Specific Means for Solving the Problems] In view of the current situation, the present inventors have made extensive studies and found that when blending various phenolic antioxidants with the aim of improving the heat aging resistance of olefin polymers, It has been discovered that by adding a piperazine derivative represented by the following general formula () in combination, a polymer material having significantly improved weather resistance as well as heat aging resistance can be obtained. (Structure of the Invention) The present invention provides a stabilizer for olefin polymers comprising a piperidine derivative represented by the following general formula (). [In the formula, R and R' represent a hydrogen atom or a methyl group, and R ² and R ⁴ represent an alkyl group having 1 to 18 carbon atoms. n and m are numbers from 1 to 3. ] The formula of a typical compound as a stabilizer represented by the formula () is shown below. N,N'-bis[2-(tetradecyloxycarbonyl)ethyl]piperazine (melting point approx. 44℃) N,N'-bis[2-(tetradecyloxycarbonyl)-1-methylethyl] (melting point approximately 52-53℃) N,N'-bis[2-(tetradecyloxycarbonyl)ethyl]-2,5-dimethylpiperazine (melting point: approx. 43°C) N,N'-bis[2-(octadecyloxycarbonyl)ethyl]piperazine (melting point approximately 57-59℃) N,N'-bis[2-(tetradecyloxycarbonyl)methyl]piperazine (melting point approximately 87-88℃) N,N'-bis[2-(tridecylcarbonyloxy)ethyl]piperazine (melting point: about 48-50°C) The amount of the piperazine derivative represented by the above general formula () of the present invention is based on 100 parts by weight of the synthetic resin. It is usually used in a proportion of 0.05 to 1 part by weight, preferably 0.08 to 0.5 part by weight. (Other additives used in combination) The stabilizer of the present invention includes a phenolic antioxidant,
When used in combination with sulfur-based antioxidants and light stabilizers, resin processed products with excellent thermal stability and weather resistance can be produced. Examples of such phenolic antioxidants include 2,6-di-t-butyl-p-cresol,
Stearyl-(3,6-di-t-methyl-4-hydroxybenzyl)thioglycolate, Stearyl-β-(4-hydroxy-3,5-di-t-butylphenyl), Propionate, Distearyl(4-hydroxy -3-methyl-5-t-butyl)
Benzyl malonate, 2,2'-methylenebis(4
-methyl-6-t-butylphenol), 4,
4'-methylenebis(2,6-di-t-butylphenol), 2,2'-methylenebis[6-(1-methylcyclohexyl)p-cresol], bis[3,
3-bis(4-hydroxy-3-t-butylphenyl)butyric acid] glycol ester,
4,4'-Butylidene bis(6-t-butyl-m-
cresol), 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane, 1,3,5-tris(3,5-di-t-butyl-4-hydroxybenzyl) -2,4,6-
Trimethylbenzene, tetrakis [methylene-3
-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]methane, 1,3,5-
Tris(3,5-di-t-butyl-4-hydroxybenzyl)isocyanurate, 1,3,5-tris[(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxyethyl)isocyanurate nurate, 2-octylthio-4,6-di(4
Examples thereof include -hydroxy-3,5-di-t-butyl)phenoxy-1,3,5-triazine and 4,4'-thiobis(6-t-butyl-m-cresol). In addition, sulfur-based antioxidants include distearylthiodipropionate, dilaurylthiodipropionate, pentaerythritol tetra (β-laurylthiopropionate), 1,3,5-tris-β-latearylthio Examples include propionyloxyethyl isocyanurate. These stabilizers are used in a proportion of 0.05 to 1 part by weight per 100 parts by weight of the synthetic resin. Heat resistance and weather resistance can be further improved by further adding a phosphite-based compound to the resin composition containing the stabilizer of the present invention. Such compounds include trioctyl phosphite, trilauryl phosphite, triphenyl phosphite, tris(nonylphenyl)
Examples include phosphite compounds such as phosphite and distearyl pentaerythritol diphosphite. In addition, depending on the use, weather resistance can be improved by further adding a light stabilizer (ultraviolet absorber). These include compounds such as benzophenone, benzotriazole, succinate, substituted acrylonitrile, and nickel complex salts. This is based on 100 parts by weight of synthetic resin.
It is used in a proportion of 0.05 to 5 parts by weight, preferably 0.1 to 2 parts by weight. In addition, if necessary, for example, pigments, fillers, foaming agents, antistatic agents, antifogging agents, surface treatment agents,
Lubricants, flame retardants, metal deactivators, nucleating agents, metal soaps, clarifying agents, processing aids, fungicides, bactericidal agents, mold release agents, and the like can also be included. (Synthetic resin) Examples of olefin polymers to which the stabilizer of the present invention is blended include α-olefin polymers such as polyethylene, polypropylene, polybutene, poly-3-methylbutene, crosslinked polyethylene, and ethylene-vinyl acetate copolymers. Polyolefins such as polymers, ethylene-propylene copolymers, and copolymers thereof can be mentioned. Example 1 (Exemplary Compound No. 1) In a four-necked flask, myristyl acrylate
10.0 g, piperazine 1.61 g, and ethanol 60 ml were added, stirred in a nitrogen stream, and started heating. After continuing heating at a temperature of 60°C for 5 hours, white crystals were precipitated when the mixture was cooled to room temperature. The results were separated and recrystallized with ethanol to obtain 10.6 g of the desired product (yield 91%). (Analytical value) H ¹ −NMR absorption spectrum [CDC ₃ , δ
(ppm)〕0.70~1.76 (54H, m), 2.26~2.87 (16H,
m), 4.05 (4H, t) IR absorption spectrum [KBr wave number (Cm ^-1 )] 2910, 1730, 1325, 1310, 1185, 1155, 720. MS [m/e, accurate mass spectrometry] 622,6 (M ⁺ ) Example 2 (Exemplary Compound No. 2) In a four-necked flask, myristyl crotonate
10.0 g of piperazine, 1.53 g of piperazine, and 60 ml of ethanol were added, stirred in a nitrogen stream, and started heating. After continuing heating at a temperature of 60°C for 10 hours, white crystals were precipitated when the mixture was cooled to room temperature. The results were separated and recrystallized with ethanol to obtain 2.7 g of the target product (yield 23.4%). (Analytical value) H ₁ −NMR absorption spectrum [CDC ₃ , δ
(ppm)〕0.66~1.83 (60H, m), 2.07~2.75 (12H,
m), 2.90-3.33 (2H, m), 4.03 (4H, t). IR absorption spectrum [KBr wave number (Cm ^-1 )] 2940, 1735, 1330, 1195, 1155. MS [m/e (relative intensity)] 650 (43, M ⁺ ), 394 (62), 326 (43), 113
(100), 87(41) Next, the stabilizing effect of the compounds of the present invention will be illustrated by application examples. Application Examples 1 to 8, Comparative Application Examples 1 to 5 Each additive shown in Table 1 was blended with 100 parts by weight of polypropylene powder with an intrinsic viscosity of 1.9 measured in tetralin at 135°C and 98% isotactic. and thoroughly mixed with a mixer. And cylinder temperature 260℃, L/D=20,20
This mixture was melt-kneaded and granulated using a mm diameter extruder. The pellets thus obtained were compression molded at 230°C into a sheet with a thickness of 0.5 mm to obtain test pieces. Heat aging resistance was determined by heating a test piece in a circulating air oven at 150°C and measuring the time required for the test piece to brown and become brittle due to oxidative deterioration. Weather resistance was measured using an Atlas 65/XW-WR xenon weather meter. When the test piece was irradiated with light at a black panel temperature of 80°C and the test piece was bent at 180°C, the test piece became brittle and cracked. The time required to do so was measured. The results were as shown in Table 1. The abbreviations in the table are as follows. 〓1 Tetrakis [3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxymethyl]methane 〓2 Product name Sanol LS770 (product name) manufactured by Sankyo Co., Ltd. 〓3 Product name Adeka Argus Co., Ltd. Made of Tinuvin
326 (Product name) 〓4 Product name Mark PEP-8 (manufactured by Adeka Argus) [Table]

Claims (1)

[Claims] 1 (1) General formula, [In the formula, R and R' represent a hydrogen atom or a methyl group, and R ² and R ⁴ represent an alkyl group having 1 to 18 carbon atoms. n and m are numbers from 1 to 3. ] A stabilizer for olefin polymers comprising a piperidine derivative represented by the following.