JPS6230134A - Stabilizer for synthetic resin - Google Patents

Abstract

PURPOSE:A novel stabilizer, consisting of a specific piperazine derivative containing phenolic residue and capable of suppressing decomposition of a synthetic resin at high temperatures by incorporation in the synthetic resin. CONSTITUTION:A stabilizer for synthetic resins consisting of a piperazine derivative expressed by formula I(R and R' are H or 14-6C alkyl; R1 and R2 are H, 1-16C alkyl or cycloalkyl; n is 1-4), e.g. N,N'-bis(3,5-di-tert-butyl-4- hydroxybenzyl) piperazine, expressed by formula II and obtained by stirring formalin and ethanol in a nitrogen gas stream, slowly dropping a solution of 2,6-di-tert-butylphenol in ethanol thereto, dropping a solution of piperazine in ethanol to the resultant mixture after the above-mentioned dropping and heating the resultant mixture at 60-65 deg.C for 4hr. 0.001-10pts.wt., preferably 0.05-2pts. wt. above-mentioned stabilizer is incorporated in 100pts.wt. synthetic resin.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a stabilizer for synthetic resins, and is useful as a novel stabilizer that suppresses high-temperature decomposition of synthetic resins.

The resin composition containing the stabilizer of the present invention is useful as an exterior material for automobiles, hollow containers, beer crates, and sheet molding materials.

[Prior art]

Generally, synthetic resins such as polyethylene, polypropylene, and ABS are susceptible to deterioration mainly due to heat and oxygen when subjected to heat molding processes such as extrusion molding, injection molding, and compression molding. This tends to cause deterioration such as deterioration of the mechanical properties of synthetic resin processed products, and has the disadvantage of causing significant disadvantages.

In order to eliminate such drawbacks, it is necessary to add one or more types of thermal stabilizers to synthetic resins to suppress thermal deterioration during processing steps. For this purpose, stabilizers such as alkylphenol compounds have conventionally been blended into synthetic resins. However, conventional stabilizers have the disadvantage that they are not always fully effective under very severe oxidative conditions.

[Specific measures to solve the problem]

To overcome such drawbacks associated with traditional stabilizers,
As a result of extensive research, the present inventors have discovered that if a certain type of piperazine derivative containing a phenol residue is added to a desired synthetic resin, a synthetic resin with excellent thermal stability can be obtained. Ta.

(Structure of the Invention) The present invention provides a stabilizer comprising a piperazine derivative having the following general formula (I).

[In the formula, R and R' are hydrogen atoms or carbon atoms 1 to 6
represents an alkyl group, and each may be different. R1 and R2 represent a hydrogen atom, an alkyl group having 1 to 16 carbon atoms, or a cycloalkyl group. n represents a number from 1 to 4. ] The formula of a typical metal compound as a stabilizer represented by the above formula (1) is shown below. The numbers assigned to these compounds are
These compounds shall be indicated in the Examples and Application Examples below.

N,N'-bis(3,5-di-t-butyl-4-hydroxybenzyl)piperazine (melting point approximately 197-198°C) N,N'-bis(3,5-di-t-butyl-2- hydroxybenzyl)piperazine (melting point approximately 261-262°C) (blank below) ・N,N'-bis(3,5-di-t-butyl-4-hydroxybenzyl)-2,5-dimethylpiperazineN,N'-bis(3,5-di-t-butyl-4-hydroxybenzyl)-2,5-dimethylpiperazine Bis(3,5-di-t-butyl-2-hydroxybenzyl)-2,5-dimethylpiperazine CH3CH3 N,N'-bis(3-t-butyl-5-methyl-2-hydroxybenzyl) -hihe 5dine CH3CH3 N,N'-bis[2-hydroxy-3-(1-methylcyclohexyl)-4-methyl-benzylcopiperazine [wherein x represents a tertiary-butyl group]. ] The piperazine derivative represented by the general formula (1) is a synthetic resin 1
It is used in a ratio of 0.001 to 10 parts by weight, preferably 0.05 to 2 parts by weight per 00 parts by weight.

(Other additives) Phenolic antioxidants, phosphite antioxidants, sulfur, etc. are added to the synthetic resin containing the stabilizer of the present invention for the purpose of preventing oxidative deterioration during processing and molding or after becoming a product. Antioxidants and the like can be used as appropriate.

Specific examples of such phenolic antioxidants include 1,
3.5-Tris(3,5-di-t-butylphenyl)
Butane, 1,3,5-tris(3,5-di-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene, Tetrakis[methylene-3-(3,5-di-t-butyl- 4-Hydroxy7enyl)propionate]methane, 1.3.5-tris(3,5-cyt-
phthyl-4-hydroxybenzyl)in cyanurate,
1,3,5-tris((3,5-sheett-7'chill-4
-hydroxyphenyl)propionyloxyethylcoin cyanurate 2-octylthio-4,6-di(4-hydroxy-3°5-di-t-butyl)phenoxy-1,
Examples include 3,5-triazine, 414'-thiobis(6-t-butyl-m-cresol), stearyl-β-(4-hydroxy-a, s-t-butylphenyl)propionate, and the like.

Specific examples of phosphite-based antioxidants include diphenyldecyl phosphite, triphenyl phosphite, tris-nonylphenyl phosphite, tributyl phosphite, tris(2-ethylhexyl) phosphite,
Tributyl phosphite, dilauryl □ acid phosphite, dibutyl 7-dophosphite, tris(dinonylphenyl) phosphite, trilauryl trithiophosphite, trilauryl phosphite, bis(neopentyl glycol) 1,4-7 chlorohexane dimethylene phosphite phosphite, distearyl pentaerythritol diphosphite, diisodecyl pentaerythritol diphosphite, diphenylamide phosphite, tris(lauryl-2-thioethyl) phosphite, tris(neptanodi mixed nonylphenyl) phosphite, hydrogenated-4,4 ′
-iso7'o hylidene diphenol polyphosphite,
diphenyl bis(4,4'-n-butylidene bis(2)
-tert-butyl-5-methylphenol)) thiogetanol diphosphite, bis(octylphenyl)-bis(4,4'-n-butylidenebis(2-tert-butyl-5
-Methylphenol)) 1.6 hexanediol diphosphite, phenyl 4.4'-isopropylidenediphenol pentaerythritol diphosphite,
Phenyldiisodecyl phosphite, tetratridecyl-4e4'-n-butylidenebis(2-11(37'thyl-5-methylphenol)diphosphite, tetratridecyl-1,1,3-)lis(2'-methyl-5 ′−
tert-butyl-4'-oxyphenyl)butane diphosphite, tetra(C12-Czs mixed alkyl) 4.4'
-isopropylidene diphenyl diphosphite, tris(4-oxy-2,5-di-tert-butylphenyl) phosphite, tris(4-,?xy-3,5-di-tert-butylphenyl) phosphite, 2-ethyl Examples include hexyl diphenyl phosphite.

Examples of sulfur-based antioxidants include distearyl thiodipropionate, dilauryl thiodipropionate, pentaerythritol tetra (β-lauryl propionate), 1
, 3.5-1 lis-β-stearylthiogproonyloxyethyl isocyanurate, and the like.

These stabilizers are used in an amount of 0.1 to 2 parts by weight, respectively, per 1 part by weight of the synthetic resin.

In addition, depending on the use, weather resistance can be improved by further adding an ultraviolet absorber. These include compounds such as benzophenones, benzotriazoles, succinates, substituted acrylonitriles, and nickel complexes.

Other pigments, fillers, foaming agents, antistatic agents, antifogging agents, surface treatment agents, lubricants, flame retardants, metal deactivators, nucleating agents, metal soaps, clarifying agents, processing aids, as necessary. , fungicide,
A bactericide, a mold release agent, etc. may be added to the synthetic resin.

(Synthetic resin) Specific examples of the synthetic resin to which the stabilizer of the present invention is blended include α-olefin polymers such as polyethylene and polypropylene; polyvinyl chloride, chlorinated polyethylene, vinyl chloride-propylene copolymers, etc. halogen-containing synthetic resin;
Polyolefins such as ethylene-vinyl acetate copolymer and ethylene-propylene copolymer, and copolymers thereof,
Polystyrene, polyvinyl acetate, acrylic resin, copolymers of styrene and other monomers (e.g., butadiene, acrylonitrile, etc.), acrylonitrile-butadiene-
Styrene copolymer, acrylic acid ester-butadiene-
Styrene copolymer, polyvinyl alcohol, polyvinyl formal, polyvinyl butyral, polyester, polyamide, polycarbonate, polyacetal, polyurethane, phenolic resin, urea resin, melamine resin,
Epoxy resin, unsaturated polyester resin, silicone resin, etc. can be used.

Next, some synthesis examples of the compound represented by the general formula (1) will be described. These manufacturing methods are merely examples, and other manufacturing methods are also possible; however, the present invention is not limited in any way by the manufacturing methods described below.

Example 1 (Exemplary Compound No. 1) In a Yotsuro flask, 8. Of (37% by weight aqueous solution) and 20 d of ethanol were added, stirred in a nitrogen stream, and a solution of 2,6-di-t-butylphenol 201 dissolved in 60 d of ethanol was slowly added dropwise.

After the dropping was completed, 3.51 ml of piperazine was dissolved in 20 d of ethanol, and the solution was slowly dropped. After finishing dropping, 6
When heated at 0 to 65°C for 4 hours, white crystals precipitated.

The crystals were separated from each other and recrystallized using cyclohexane to obtain the desired product 17.09 (yield: 65%).

(Analysis value) “H-NMR absorption spectrum # (CD C13, δ(p
pm)) 1.43 (36H, S), 2.46 (8H, S
).

3.43 (4H, S), 5.05 (2H, S).

7.03 ('4 H,S) IR absorption spectrum + ([13r, wave number (m-''), 13
650, 297'0, 2810, 1430.1225,
1610 M5 (m/e, (relative intensity))] 523 (16, yr”), 304 (44).

303 (98), 219 (100), 203 (30),
161 (36) Example 2 (Exemplary Compound No. 2) In a four-piece flask, 8.5% formalin was added. Of (371% aqueous solution) and 20 wg of ethanol were added, stirred in a nitrogen stream, and a solution of 2,4-di-t-butylphenol 202 dissolved in 60 d of ethanol was slowly added dropwise.

After completion of the dropwise addition, white crystals were precipitated by heating at 60 to 65° C. for 4 hours.

The crystals were separated from each other and recrystallized from cyclohexane to obtain the desired product 16.59 (yield: 63%).

(Analysis + K) 1H-NMR absorption spectrum (CDCl2, δ (ppm
)) 1.28 (1sH,S ), 1.42 (18H
,S ), 2.63 (8H,S ), 3.69 (4
H, S), 6.80 (zH, d), 7.20 (2H
, S ), 10.56 (2I(,5) IR absorption spectrum (KBr, wave number (il)) 2975
．． 1481.1460.1 438.1 3 69.1
2 5 5.1 23 8MS (m/e, (relative intensity)) 523 (33, M”), 507 (32).

304 (59), 303 (62), 276 (27), 2
19 (100), 203 (62) Next, by application example,
The stabilizing effect of the compounds of the present invention is illustrated.

Application Examples 1 to 4, Comparative Application Examples 1 to 2 A stabilizer was added to 100 parts by weight of polypropylene powder with an intrinsic viscosity of 1.9 measured in tetralin at 135°C and an isotactic value of 9870, and a stabilizer was added to the fkm processing shown in Table 1. and thoroughly mixed with a mixer. Then, the mixture was melt-kneaded and granulated using an extruder having a diameter of L/D = 20.20 m at a cylinder temperature of 260°C.

The MFR of the pellet thus obtained at 230°C (JI
SK-6758) was measured and defined as MFRt. Furthermore, the pellet was passed through the extruder three times under the same conditions as above, and the MFR at 230° C. of the obtained pellet was defined as MFR4. MFR
is one index of molecular weight, and a large MFR corresponds to a small molecular weight. In other words, the fact that MFRI and MFR4 are small and the difference between MFRI and MFR4 is small means that the decrease in molecular weight due to oxidative deterioration in the extruder is small, and if a stabilizer is used, the effect of the stabilizer is small. is large. The results are shown in Table 1 (margins below).

Claims (1)

[Claims] 1) General formula, ▲ Numerical formula, chemical formula, table, etc. ▼ [In the formula, R and R' are hydrogen atoms or carbon atoms of 1 to 6
represents an alkyl group, and each may be different. R_1 and R_2 represent a hydrogen atom, an alkyl group having 1 to 16 carbon atoms, or a cycloalkyl group. n represents a number from 1 to 4. A stabilizer for synthetic resins consisting of a piperazine derivative represented by ].