JPH02258803A - Organic peroxide composition and production of modified plastics using same composition - Google Patents

Abstract

PURPOSE:To obtain the title composition consisting of an organic peroxide and free radical capturing agent and capable of carrying out modification of degradation type plastics without raising of melt flow index. CONSTITUTION:The aimed composition consisting of an organic peroxide (e.g. benzoyl peroxide) and free radical capturing agent [preferably 2,6-di-tert. butyl-4- methylphenol, n-octadecyl-3-(3',5'-di-tert. butyl-4'-hydroxyphenyl)propionate, 2,2'-methylenebis-(4-methyl-6-tert. butylphenol), 2-tert. butyl-6-(3'-tert. butyl-5'- methyl-2'-hydroxybenzyl)-4-methylphenylacrylate, etc.]. The composition is added to a degradation type plastics to modify the degradation type plastics.

Description

[Detailed Description of the Invention] [Industrial Application Field] The organic peroxide composition of the present invention is mainly used for disintegrating plastics among polyolefins (those whose main chains undergo scission when treated with an organic peroxide). It is used for blending modified and disintegrating plastics with other thermoplastics using reactive monomers, etc.

[Conventional technology]

Conventionally, polyolefins have been widely used because they are relatively inexpensive and have excellent mechanical properties, as well as excellent chemical resistance, oil resistance, and abrasion resistance. Difficult to adhere to and blend with polar plastics. In order to improve these drawbacks, for example, a method of adding a modifier such as an unsaturated carboxylic acid or its derivative to polyolefin and performing a melt-kneading treatment in the presence of an organic peroxide, and a method of melt-kneading the polyolefin and other thermoplastics. A well-known method is to perform a melt-kneading process by adding a modifier such as an unsaturated carboxylic acid or a derivative thereof and an organic peroxide when blending.

[Problem to be solved by the invention]

Among polyolefins, collapsible plastics are made by adding a modifying agent such as an unsaturated carboxylic acid or its derivatives, and then performing melt mixing treatment in the presence of an organic peroxide. At the same time, the melt flow index (hereinafter abbreviated as MFI) of polyolefins increases significantly, causing a decline in mechanical properties, which is a major problem.In order to prevent the increase in MFI, low-temperature decomposition type organic peroxides are used. Attempts have been made to treat at low temperatures using benzoyl peroxide (for example, benzoyl peroxide) or to reduce the amount of organic peroxide added, but these methods hardly cause the desired grafting reaction of the modifier, and polar groups Since the grafting efficiency, which indicates the amount of introduced carbon dioxide, is low, modification is not carried out sufficiently.Furthermore, if an excessive amount of a modifying agent such as an unsaturated carboxylic acid or its derivative is added, the increase in MFI can be suppressed to some extent, but after treatment A large amount of unreacted modifier remains in the polymer, which poses major problems in terms of toxicity, coloring, odor, and economics.Unsaturated carboxylic acids and Even when a modifier such as a derivative thereof and an organic peroxide are added to perform melt mixing treatment, the compatibility of both polymers is improved by the pressure of the organic peroxide added to improve the compatibility of both polymers. Even if the process is carried out, the MFI increases significantly after treatment, resulting in a decrease in mechanical properties, so it is currently almost impossible to put it into practical use.Providing a modified polyolefin with high crafting efficiency without increasing the MFI. Or, until now, no effective method has been found to improve the compatibility between collapsible plastics and other thermoplastics and to obtain a homogeneous blend without increasing MFI. A solution to this problem was required.

[Means to solve the problem]

The present inventors have proposed that MF using organic peroxides can be used in modification of collapsible plastics with reactive monomers or blends of collapsible plastics with other thermoplastics.
As a result of intensive studies on preventing the increase in I, we have found that by using a composition in which a free radical scavenger is mixed with an organic peroxide, the desired grafting reaction and blending can be carried out and the increase in MFI can be prevented. It was discovered that this method has a significant effect, leading to the present invention. In addition, the collapsible plastic in the present invention specifically includes isotactic or syndiotactic polypropylene or probylene α
-Olefin copolymers. That is, the present invention is an organic peroxide composition consisting of an organic peroxide, preferably 1 to 60% by weight, and a free radical scavenger, preferably 99 to 40% by weight. For example, when a mixture composition hereinafter abbreviated as a mixed composition is used for modifying polypropylene with an unsaturated carboxylic acid, it has become possible for the first time to obtain a modified polymer with high grafting efficiency and an MFI almost the same as that of untreated polypropylene. Further, the mixed composition of the present invention may be made of, for example, polypropylene and ethylene-polypropylene using an unsaturated carboxylic acid as a compatibilizer.
When used in a blend of saponified vinyl acetate copolymer (hereinafter abbreviated as EVOH), the MFI is approximately the same or lower than that of a blend of both polymers only (,
For the first time, it has become possible to produce a uniform polymer with completely improved compatibility.

In this case, if only the organic peroxide is used in the present blade, the MFI will increase significantly, but the inventors used the organic peroxide and the free radical scavenger simultaneously in the grafting reaction or blending. In this case, the radicals of the organic peroxide decomposed by heat are not consumed by the full-pressure free radical scavenger, but instead act effectively on the hydrogen abstraction reaction of the disintegrating plastic, and 2% of unsaturated carbon, The inventors discovered that a free radical scavenger effectively promotes the grafting reaction of monomers, while having an excellent effect on preventing main chain scission of collapsible plastics, thereby preventing an increase in MFI, leading to the present invention. .

Examples of organic peroxides used in the mixed composition of the present invention include Eva,
Benzoyl peroxide, 0-chlorhenyl peroxide, P-chlorobenzoyl peroxide, 2
．． 4-dichlorobenzoyl peroxide, diacyl peroxides such as 0-methylbenzoyl peroxide, tert-butyl peroxybenzoate,
Alkyl peresters such as tert-butyl peroxy-2-ethylhexanoate, bar carbonates such as tert-butyl peroxy isopropyl carbonate, 1,1-di-tert-butyl peroxy-3,3°5 -trimethylcyclohexane, 1,1
-ditertiary-butylperoxycyclohexane, 4
．． 4-ditertiarybutyl peroxyvalene acinodon normal butyl ester, dicumyl peroxide, ditertiary butyl peroxide, 2,5-dimethyl-2,5-di(tert-butyl) peroxy)hexane, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexyne-3, tert-butylcumyl peroxide,
These include dialkyl peroxides such as 1,3-bis(tert-butylper4xy)4soprobylbenzene.

The free radical scavenger used in the mixed composition of the present invention is
In general, stabilizers, antioxidants, anti-aging agents, etc. may be used, but non-staining agents are preferred. For example, 2,6-
ditertiarybutyl-4-methylphenol, n-octadecyl-3-(3',5'-ditertiarybutyl-4'-hydroxyphenyl)gropionate, 2,2
'-Methylenebis-(4-methyl-6-tert-butylphenol), 2-tert-butyl-6-(3
'-tert-butyl-5'-methyl-2'-hydroxybenzyl)-4-methylphenylacrylate, 4
．． 4'-thiobis(3'-methyl-6-tert-butylphenol), tetrakis[methylene-3-(3'
, 5'-tert-7'thyl-4'-hydroxyphenyl) propionate comethane, 4,4'-butylidene bis-(6-tert-butyl metacresol), 2
．． 2'-methylene/bis-(4-ethyl-6-tert-butylphenol), 2,6-ditertiarybutyl-4-hydroxymethylphenol, 2,6-ditertiarybutyl-n-butylphenol, 1,3.5 -trimethyl-2,4,6-)lis(3,5-ditertiarybutyl-4-hydroxybenzyl)benzene, 1,1
．． 3-tris-(2-methyl-4-hydroxy-5-
tert-glylphenyl)butane, tetrakis(2
,4-ditertiarybutylphenyl) -4,4'-
Biphenylene diphosphonite, tris(2-methyl-4-hydroxy-5-tert-butylphenyl)
Pig 7 grade.

To mix the mixed composition in the present invention into the polymer,
Banbury mixer - Ribbon blender - Paddle mixer Mixmaster Pony mixer Nauta mixer Concrete mixer Omni mixer V-type mixer, double cone mixer, universal mixer, kneader Henschel mixer, etc. can be used. Mixed compositions that are solid at room temperature may be mixed at room temperature or at a temperature above the melting point. If the mixed composition is in liquid form, it may be easier to use it if it is made into powder using fillers such as silica or calcium carbonate. The amount of the mixed composition of the present invention added is preferably 0.05 to 20 parts by weight, more preferably 0.1 to 10 parts by weight, per 100 parts by weight of the polymer.

Furthermore, even if the organic peroxide and the free radical scavenger are not made into a mixed composition in advance and are mixed into the polymer separately, if both are mixed at the same time, the effect will be exactly the same as when they are mixed as a mixed composition. It is possible to return. The conditions for heat treatment after mixing the mixed composition with the polymer vary depending on the type of polymer and the processing machine used, but - for boat fishing, a temperature of 130°C to 300°C and a time of 1 to 20 minutes is appropriate. . The heat treatment can be carried out using a ball mixer, a screw extruder, a kneader, a kneading extruder, a high-pressure press, or the like.

〔Example〕

Hereinafter, the present invention will be specifically explained with reference to Examples and Comparative Examples. The polymers used in the Examples and Comparative Examples of the present invention are as follows.

(Abbreviation) pp: Homopolypropylene Highball J300 MFI = 1.4 <2160g/2300C) Manufactured by Mitsui Petrochemical Industries Ltd. PA = Nylon ~ 6 P1030 MFI = 4.0 (2160g/230'C) Manufactured by Ube Industries Ltd. EVOH: Saponified ethylene/vinyl acetate copolymer, ethylene copolymerization ratio 29 molt, saponification rate 98% MFI=4.2 (2160g/230°C) Kuraray ■
Company manufactured Examples 1 to 5. Comparative Examples 1 to 4 Predetermined amounts of an organic peroxide and a free radical scavenger were mixed at room temperature in a universal mixer as shown in Table 1 to prepare a mixed composition.

Table-1 D-bar force dox 14: 1,3-bis(tert-butylperoxy)inglobilbenzene 2) Kayahexa AD: 2,5-dimethyl-2,5
-di(tert-butylperoxy) Hexane or higher, manufactured by Kagaku Nouri ■ 3) Sumilizer GM: 2-tert-butyl-6-(3'-tert-butyl-5'-methyl-2
'-Hydroxybenzyl)-4-methylphenyl acrylate Sumitomo Chemical Co., Ltd. Haake Buchler twin screw extruder Rheom
ex TW-100 (screw diameter, front: 19.7mm
, rear: 31.1 mm, length 331 mm) was heated to the following predetermined temperature. Temperature settings are Zone 1 = 100°C, Zone 2 = 190°C, Sort '3 = 230°C. PP, water maleic acid (reagent grade) (hereinafter abbreviated as MAR), and a mixed composition were blended in the proportions shown in Table 2 and mixed well. Rotate the twin-screw pushing machine at 5 Q r, p, m, and press P from the hopper.
A blend of P, MAH, and a mixed composition was charged and extrusion was performed. The MFI and grafting efficiency of the obtained modified polymer were measured. Grafting efficiency was calculated using the following formula.

For comparative examples, only organic peroxide was used instead of the mixed composition. The results are summarized in Table-2.

Table 2 1) Cadox B: Penzoyl peroxide agent Manufactured by Nouri ■ Table 11 From the results in Table 2, the mixed composition of the present invention efficiently (proceeds) the grafting reaction, and the modified PP
It is clear that it has a significant effect on preventing the increase in MFI of .

Examples 6-15. Comparative Examples 5 to 10 Predetermined amounts of organic peroxide and free radical scavenger were mixed at room temperature using a universal mixer as shown in Table 3 to prepare mixed compositions.

Table-3 The temperature was raised. PP, EVOH, MAH, and a mixed composition were blended in the proportions shown in Table 4 and mixed well. This blend was introduced into the hopper of a kneading extruder and extruded. The MFI of the obtained blend was measured, and the uniformity was observed using an electron microscope. In the comparative example, an organic peroxide was used instead of the mixed composition. The results are summarized in Table 4.

Table 4 1) Kayacumyl D = dicumyl peroxide 2) Kayahexa YD: 2,5-dimethyl-2,5-di(tert-butylperoxy) Hexine-3 or above, manufactured by Kayaku Nouri ■ 3) P- EPQ: Tetrakis (2,4-ditertiarybutylphenyl) -4,4'-biphenylene diphosphonite Sandozhi C8I company, MInl-Max kneading extruder C5-194
Table 4 (Continued) Uniformity of blend ○: Completely homogeneous blend △ Partial phase separation ×: Not blended at all Table 31 From the results in Table 4, when the mixed composition of the present invention is used for blending PP and EVOH, MFI
It is clear that a homogeneous blend can be obtained without increasing the temperature. In some cases, a homogeneous blend can be obtained using only organic peroxide (Comparative Example 1' shows 9
．． l'&tlO), its MFI has increased significantly.

The temperature of the rotor and hesogoo was raised to 260°C. PP, PA, MAH, organic peroxide, and free radical scavenger were thoroughly mixed in the proportions shown in Table 5. In this example, the organic peroxide and the free radical scavenger were not prepared as a premixed composition, but were separately added and mixed to the polymer at the same time. The blend was introduced into the hopper of a kneading extruder and extruded. The MFI of the obtained blend was measured, and the uniformity was observed using an electron microscope. In the comparative example, only organic peroxide was used. The results are summarized in Table-5.

Table 5 1) Irganox 1010: Tetrakis [methylene-3-(3; 5'-ditertiarybutyl-4'-hydroxyphenyl) flobionate cometan Ciba Geigy (manufactured by Kikisha Table 5 (Continued) Example 22~ 3° As a free radical scavenger, n-octadecyl-3-
The same operations as in Examples 16 to 21 were performed except that (3',5'-ditertiarybutyl-4'-hydroxyphenyl)propionate and 4,4'-butylidenebis-(6-tert-butylmetacresol) were used. I did it. The results are summarized in Table-6.

Table-6 1) MARK AO-50: n-octadecyl-
3-(3',5'-diter7yarybutyl-4'-hydroxyphenyl)probionate Adeka Argus Chemical Co., Ltd. 2) Sumilizer BBM-8: 4,4'-butylidenebis-(6-tert-butylmetacresol) Sumitomo From the results in Table 51 and Table 6, manufactured by Kagaku ■, it was found that even when the organic peroxide and the free radical scavenger were not made into a mixed composition in advance, but were separately added and mixed together with the polymer, the MFI of the blend was
It is clear that rise can be prevented and a homogeneous blend can be obtained.

〔Effect of the invention〕

The present invention makes it possible for the first time to modify collapsible plastic without increasing the MFI, which was previously impossible, and also makes it possible to increase the MFI in blends of collapsible plastic and other thermoplastics. For the first time, it became possible to obtain a homogeneous blend without any problems. Therefore, the industrial value of the present invention is extremely large.

Patent applicant: Kayaku Nouri Co., Ltd.

Claims (1)

[Claims] 1. An organic peroxide composition comprising an organic peroxide and a free radical scavenger. 2. A method for modifying degradable plastics, which comprises adding an organic peroxide and a free radical scavenger. 3. A method for producing degradable plastics and other thermoplastic blends, which comprises adding an organic peroxide and a free radical scavenger. 4. The free radical scavenger is 2,6-ditertiarybutyl-4-methylphenol, n-octadecyl-3
-(3',5'-ditertiarybutyl-4'-hydroxyphenyl)propionate, 2,2'-methylenebis-(4-methyl-6-tert-butylphenol), 2-tert-butyl-6-(3'-tert-butyl-5'-methyl-2'-hydroxybenzyl)
-4-methylphenyl acrylate, 4,4'-thiobis-(3'-methyl-6-tert-butylphenol), tetrakis [methylene-3-(3',5'-tert-butyl-4'-hydroxyphenyl) Propionate] Methane, 4,4'-butylidenebis-(6-tert-butylmetacresol), 2,2'-methylenebis-(4-ethyl-6-tert-butylphenol), 2,6-ditertiary-butyl-4 -Hydroxymethylphenol, 2,6-ditertiarybutyl-n-butylphenol, 1,3,5-trimethyl-2
,4,6-tris(3,5-ditertiarybutyl-4
-hydroxybenzyl)benzene, 1,1,3-tris-(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, tetrakis(2,4-ditertiarybutylphenyl)-4,4'-biphenylene The organic peroxide composition according to claim 1, which is a range phosphonite, tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane.