JPS61190545A - Chlorine-containing ethylene resin composition - Google Patents

Abstract

PURPOSE:To provide a composition of high thermal stability, comprising chlorine-contg. ethylene resin, triethylene glycol bis-3-(3-t-butyl-4-hydroxy-5- methyl-phenyl)propionate and inorganic phosphoric acid salt. CONSTITUTION:The objective composition comprising (A) 100pts.wt. of either vinylidene chloride resin or vinyl chloride resin, (B) 0.0005-5(pref. 0.005-0.5)pts. wt. of triethylene glycol bis-3-(3-t-butyl-4-hydroxy-5-methyl-phenyl)propionate and (C) 0.0001-1(pref. 0.0005-0.1)pt.wt. of inorganic phosphoric acid salt, pref. at least one sort of salt selected from pyrophosphoric acid salts and monobasic phosphoric acid salts, more pref. a combination of both. The production process is as follows: chlorine-contg. ethylene monomer is polymerized, preferably in the presence of both the components (B) and (C) beforehand.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a chlorine-containing resin suitable for obtaining molded products of chlorine-containing ethylene resin such as vinylidene chloride resin or vinyl chloride resin, which has excellent thermal stability. The present invention relates to an ethylene resin composition.

l A chlorine-containing ethylene resin such as rice-colored Ibaragaa vinylidene chloride resin or vinyl chloride resin can be made into a film by hot extrusion molding.
Formed into bottles, threads, etc. At that time, the resin is susceptible to partial thermal deterioration due to heat and oxidative deterioration due to oxygen, which often results in coloring of the molded product and a significant loss of product value. When exposed to light, it may become colored, resulting in a decline in quality and commercial value. Heat stabilizers are generally used to prevent coloring caused by heat and light, and stabilizers that are hygienically harmless are required, especially in the food packaging field, and a large amount of research has been conducted in response to this demand. It is.

Recently, it has been discovered that antioxidants have the effect of significantly preventing thermal deterioration and oxidative deterioration of these chlorinated ethylene resins, and the use of many antioxidants has been proposed.
For example, in the copolymerization of vinylidene chloride previously proposed by the present applicant, a method of carrying out copolymerization in the presence of 3.5 di-tert-butyl-4-hydroxytoluene, n-propyl gallate, tocopherol, etc. (Japanese Patent Publication No. 55, No. 34166) or octadecyl 3.5 ditertiary 8. Butyl-4-hydroxyhydrocinnamate and triethylene glycol bis-3-(
A method of mixing 3-t-butyl-4-hydroxy-5-methyl-phenyl) propionate, etc. with chlorine-containing ethylene resin (Japanese Patent Publication No. 10894/1989, Japanese Patent Publication No. 55/1983)
27120) etc. are already known.

However, the use of each of the antioxidants mentioned above has an effect on the thermal stability and light stability of chlorine-containing ethylene resin, but it depends on the processing conditions of the resin. In view of the current situation where the conditions are becoming more severe, there is a demand for chlorine-containing ethylene resins with even better thermal stability and light stability.The present inventor has conducted extensive research in order to meet these demands. As a result, it was found that a specific proportion of triethylene IJ,
The above problems were successfully solved by incorporating colbis-3-(3-tertiarybutyl-4-hydroxy-5-methyl-phenyl)propionate and an inorganic phosphate.

That is, in the present invention, triethylene glycol bis-
By mixing 3-(3-tertiarybutyl-4-hydroxy-5-methyl-phenyl) propionate and inorganic phosphate with the chlorinated ethylene resin in a certain ratio instead of each individually, their synergistic effect can be achieved. By using the above methods, it is possible to obtain a chlorinated ethylene resin composition such as a vinylidene chloride resin or a vinyl chloride resin composition, which has a high level of thermal stability that cannot be achieved by each of them alone. Furthermore, the present invention uses triethylene glycol bis-3-(3-tertiarybutyl-4-hydroxy-5-methyl-phenyl)propionate, which can impart excellent thermal stability to the resin as described above. By selecting octadecyl-3.5 ditertiarybutyl-4, which is a conventionally used antioxidant,
- A resin that shows excellent performance in gear oven tests and roll kneading tests that cannot be obtained with hydroxyhydrocinnamate or 3.5 di-tert-butyl-4-hydroxytoluene, even when used in combination with an inorganic phosphate. It becomes possible to obtain. In addition, by using the resin composition according to the present invention, it is possible to produce a film that has little decomposition in an extruder, can be processed continuously over a long period of time, and has very little coloration.
It also becomes possible to easily mold bottles and the like.

The present invention will be explained in detail below.

In addition, the characteristics of the present invention include 100 parts by weight of chlorine-containing ethylene resin and 0.0005 to 5 parts by weight of triethylene glycol bis-3-(3-tertiarybutyl-4-hydroxy-5-methyl-phenyl)propionate. part and inorganic phosphate 0.
0001 to 1 part by weight of a chlorine-containing ethylene resin composition.

The term "chlorine-containing ethylene resin" as used herein means vinylidene chloride resin and vinyl chloride resin. Includes copolymers with 5 to 35% by weight of one or more of esters (alkyl groups with 1 to 121 carbon atoms), methacrylic acid alkyl esters (with 1 to 12 carbon atoms), or acrylonitrile. The vinyl chloride resin includes polyvinyl chloride and a vinyl chloride copolymer containing vinyl chloride as a main component.

Triethylene glycol bis-3-(3-tertiarybutyl-4-hydroxy-5-methyl-phenyl)propionate used as an antioxidant in the present invention has a melting point of 7.
It is a crystalline powder having a temperature of 6 to 79° C., and is commercially available with the following formula <1), for example, under the trade name IRGANOX 245 (manufactured by Ciba Geigy).

In addition, the inorganic phosphates used in combination as the above-mentioned antioxidant include pyrophosphates such as sodium, potassium or calcium pyrophosphate; monophosphates such as sodium, potassium or calcium monophosphate; orthophosphate; Examples include acid salts, metaphosphates, and diphosphates,
In particular, it is preferable to use at least one salt selected from birophosphate and primary phosphate because it has a great synergistic effect with the antioxidant.

Further, it is preferable to use the birophosphate and the primary phosphate together in amounts, in which case the birophosphate and the primary phosphate are in a range of 371 to 1:3 (weight ratio), particularly 1: It is preferable to use the ratio of 1.

In the present invention for controlling dishwashing, the antioxidant made of the propionate (hereinafter simply referred to as antioxidant) is added to 100 parts by weight of the chlorine-containing ethylene resin, preferably from 0,000 to 5 parts by weight. in a proportion of 0.005 to 0.5 parts by weight, and the above inorganic phosphate in a proportion of 0.0001 to 1 part by weight, preferably 0.00 parts by weight.
If the antioxidant is used in an amount less than 0.0005 parts by weight, a synergistic effect on thermal stability can be obtained when used in combination with an inorganic phosphate. On the other hand, if more than 5 parts by weight is used, the polymerization step to obtain the above resin and other adverse effects will be observed. Furthermore, when the inorganic phosphate is used in an amount less than 0.0001 part by weight, the synergistic effect obtained when used in combination with the antioxidant is poor, whereas when used in an amount greater than 1 part by weight, the resultant resin composition The transparency of the molded product will be impaired.

In the present invention, in order to incorporate the above-mentioned antioxidant and inorganic phosphate into the chlorinated ethylene-based resin, the above-mentioned both are added to the resin and mixed, or the chlorinated ethylene-based resin is added to the resin in the polymerization step for producing the resin. It may be added and mixed with the monomer together with other polymerization aids, and furthermore, it may be added and mixed with the slurry form after polymerizing the monomer. It is also possible to add and mix the above together with other processing aids to the powdered material before processing.

The above antioxidant and inorganic phosphate may be added in their entirety at the same time, or may be added separately. It may be contained in the previous resin.

Furthermore, when adding the antioxidant and inorganic phosphate to the resin, they may be dissolved in a solvent or water, or may be added directly to the resin in powder form.

In particular, if an antioxidant and an inorganic phosphate are pre-existing in the polymerization system during the polymerization step of chlorine-containing ethylene monomers, their presence will prevent the oxidation of the monomer during polymerization and will improve the polymerization system. This is actually advantageous, since it is possible to adjust the pH of the resin appropriately, resulting in a resin composition with much better thermal stability than when it is added after polymerization. In the case of vinylidene chloride resin, the oxidative decomposition of hetamine during polymerization is particularly significantly prevented, so there is an advantage that a completely odorless resin composition can be obtained.

As described above, the resin composition according to the present invention is characterized in that the chlorine-containing ethylene resin contains the above-mentioned antioxidant and inorganic phosphate in a specific ratio. It goes without saying that additives commonly used in ethylene resins, such as other antioxidants, plasticizers, stabilizers, ultraviolet absorbers, and the like, may be appropriately added and included as necessary.

EXAMPLES The present invention and its effects will be explained in more detail with reference to Examples below. In addition, comparative examples are also shown in order to clearly demonstrate the effects of the present invention.

Preparation of chlorine-containing ethylene resin composition: 3.2 g of methoxycellulose, 0.8 g of sodium pyrophosphate, and monobasic sodium phosphate were placed in a 101 stainless steel autoclave equipped with a chi-shaped stirrer. After adding 4800 g of deionized water in which 0.8 g was dissolved and purging the system with nitrogen, 3.84 g of diisopropyl peroxydicarbonate, 32.0 g of epoxidized soybean oil, and the various types shown in Table 1 were added. 0.64g of antioxidant and 0.3
Added and melted 2g of vinylidene chloride monomer 249
A mixed monomer mixture of 6 g of vinyl chloride and 704 g of vinyl chloride was introduced under pressure.

The above raw material mixture was stirred until its internal temperature was 42.0°C.
The temperature was increased to start polymerization and reaction, and after that, the temperature was increased to
The temperature was raised continuously to 6.0°C and maintained at this temperature after 34 hours, and when ΔP (the pressure difference between the pressure at the start of polymerization and the pressure at the end of polymerization) reached 3.8 kg/aj, the polymerization was stopped. In order to stop the reaction, a solution of 0.64 g of distearyl thiodipropionate dissolved in 50 g of vinylidene chloride monomer was injected into the polymerization system, stirring was continued for 1 hour, the internal pressure was released, and the polymer slurry was taken out. . The obtained slurry is
After hydrophilization, the polymer was dried in a dryer at 50° C. for 20 hours to obtain 2.56 kg of polymer powder, and the polymerization yield was about 80%.

The types of antioxidants used here and the respective amounts of sodium pyrophosphate and monobasic sodium phosphate in parts by weight per 100 parts by weight of the above polymer are as follows:
As shown in the table. In addition, Comparative Example 3 is an example in which only the above-mentioned inorganic phosphate was added without adding an antioxidant.

Side 1J side 1: Polymerization was carried out in the same manner as in Example 1, except that phosphate was not added during the polymerization step. That is,
In Example 3, 0.8 g of sodium pyrophosphate and 0.8 g of dibasic sodium phosphate dissolved in 50 g of deionized water were added to the slurry after polymerization, and the slurry was dehydrated and then dried.

Polymer 100 with phosphate content in the resulting polymer
The weight parts per weight part are as shown in Table 2.

In Examples 4 to 8, the slurry after polymerization was directly dehydrated and dried, and 100 g of the obtained polymer was uniformly sprayed with phosphate in the amount shown in Table 2 dissolved in deionized water. and vacuum-dried at room temperature to obtain a polymer (vinylidene chloride resin composition). Obtained polymer 1
The parts by weight of the phosphate salt per 00 parts by weight were as shown in Table 2.

A polymer was obtained by carrying out polymerization in the same manner as in Example 1, except for changing the amounts of the phosphates.

That is, in Example 9, sodium pyrophosphate was 0.0
8 g and 0.08 g of monobasic sodium phosphate were added.

In Example 10, 8.0 g of sodium pyrophosphate and 8.0 g of monobasic sodium phosphate were added.

The slurry obtained by polymerization was dehydrated and dried to obtain each polymer. The respective parts by weight of sodium pyrophosphate and monosodium phosphate per 100 parts by weight of polymer are 0.0006 parts by weight and 0.0006 parts by weight, respectively, in Example 9, and 0.06 parts by weight, respectively, in Example 10. and 0.0
It was 6 parts by weight.

In Comparative Example 4, a polymer was obtained by carrying out polymerization in the same manner as in Example 1, except that no phosphate was added. 1
Next, a thermal stability test was conducted on each of the remers (resin compositions) obtained in Examples 1 to 10 and Comparative Examples 1 to 4 by the method shown below.

Thermal stability test method: ■ Test using a gear oven 28 g of the above resin composition (polymer) was heated in a press for 17 g.
After preheating at 5℃ for 2 minutes, pressurize at 150kg/ajG for 1 minute to create a breath punch with a thickness of 1+u+, 3cm x 3cm■
Cut into test pieces. This test piece was placed in a gear oven at 150°C and taken out one by one every 10 minutes, and the degree of yellowing was measured using a color difference method (MODE!L TCA-1 reflection method manufactured by Tokyo Juishiki ■). Measure the time it takes.

Test by crawl kneading 150 g of the above resin composition (polymer) was mixed in a 6-inch coll at 19 rpm, 142°C, and a clearance of 0.4.
Color I of the sheet taken out after kneading for 3 minutes under gmD conditions
I (b value) was measured using a color difference meter [MODEL Z- manufactured by Nippon Heavy Industries Ltd.
1001) p].

A large number of b values (+) indicates a large degree of yellowing.

The results are shown in Table 3.

Furthermore, the following dehydrochlorination test was conducted for each resin composition obtained in Example 1 and Comparative Example 1.

Dehydrochloric acid test: 2 g of polymer was placed in a glass test tube, the test tube was immersed in an oil bath, and the time required for Congo red test paper to change color at each temperature in the range of 140 to 180° C. was measured.

The results are shown in Table 4.

As seen in Tables 3 and 4 of Table 4, according to the present invention,
Triethylene glycol bis-3-(3
-tersiabutyl-4-hydroxy-5-methy/L'
-pheni/lz) propionate (IRGANOX 2
It can be seen that by using 45) and including it in a chlorine-containing ethylene resin composition in combination with an inorganic phosphate, the thermal stability of the resin composition is significantly improved due to the synergistic effect of the two.

Taishu Kamido Nijo 1 In a 101-volume stainless steel polymerization can, partially saponified polyvinyl alcohol (saponification degree 80 sole%, polymerization degree 1700) was added.
) and 6 kg of deionized water in which each phosphate shown in Table 5 below was dissolved, and after purging the system with nitrogen, diisopropylperoxydicarbonate) 1.5 g
and 3 kg of vinyl chloride (VC) monomer were press-fitted.

Next, the temperature of the above charging mixture was raised to 57°C, and polymerization was carried out while maintaining the temperature at 57°C. When the pressure had decreased by 3 kg from the saturated vapor pressure of vinyl chloride hexamer at 57°C, the mixture used in Example 1 was heated. Antioxidant IRGANOX2450.
A solution prepared by dissolving 6 g of methanol in 10 g of methanol was injected under pressure, and after stirring was continued for 20 minutes, the internal pressure was released and the polymer slurry was taken out. After dehydration, each slurry obtained was
It was dried for 20 hours in a dryer at °C to obtain 2.6 kg of powder. Yield 87%.

Examples 1) to 13 except that phosphate was not added
Polymerization was carried out in the same manner as above to obtain a polymer.

Polymerization was carried out in the same manner as in Example 1), except that 0.6 g of 3.5 ditertiary butyl-4-hydroxytoluene (BHT) was used as the antioxidant to obtain a polymer.

Cooking test 1 Polymerization was carried out in the same manner as in Example 1, except that no antioxidant was added to obtain a polymer.

Cooking dish 1 Polymerization was carried out in the same manner as in Example 1) except that neither the antioxidant nor the phosphate was added to obtain a polymer.

Next, the following thermal stability test was conducted on each of the polymers obtained in Examples 1) to 13 and Comparative Examples 5 to 8.

Thermal stability test: 1.0 parts of epoxidized soybean oil per 100 parts by weight of polymer.
0 parts by weight of cadmium stearate, 0.3 parts by weight of cadmium stearate, and 0.2 parts by weight of barium stearate were added and mixed. 100 g of the mixture was heated with a 6-inch roll at a temperature of 160° C. under conditions of 19 rpm and a clearance of about 0.7 mn+. Knead for 3 minutes and cut the resulting sheet into 3cm x 3c
Cut into specimens of size m.

The test piece was placed in a gear oven at 185°C and after 60 minutes had elapsed, it was taken out every 10 minutes and the time until black spots appeared (blackening time) was measured to determine thermal stability.

The results of the above test are shown in Table 5.

As seen in Table 5, it can be seen that the thermal stability of the resin compositions (Examples 1) to 13) according to the present invention is superior to Comparative Examples 5 to 8.

Claims (3)

[Claims] (1) 100 parts by weight of chlorinated ethylene resin and triethylene glycol bis-3-(3-tertiarybutyl-4-
Hydroxy-5-methyl-phenyl)propionate 0
．． 0005~5 parts by weight and inorganic phosphate 0.0001~
A chlorine-containing ethylene resin composition comprising 1 part by weight. (2) Claim No. 1, wherein the inorganic phosphate is at least one selected from pyrophosphate and primary phosphate.
) The chlorine-containing ethylene resin composition described in item 1. (3) Triethylene glycol bis-3-(3-tertiarybutyl-4-hydroxy-5-
The chlorine-containing ethylene resin composition according to claim 1, which is obtained by polymerization in the presence of methyl-phenyl) propionate and an inorganic phosphate.