JPS5884846A - Copolymer composition - Google Patents

Abstract

PURPOSE:To obtain an ethyleric copolymer having antistatic properties, with reduced melt viscosity during molding process with retaining its original characteristics, comprising an ionic ethylenic copolymer and a sulfonic acid group- contg. organic compound of relatively low molecular weight. CONSTITUTION:The objective composition can be obtained by blending, in molten state. (A) 100pts.wt. of an ionic ethylenic copolymer having both unsaturated carboxylic acid group and its metal salt group (pref. sodium salt one), preferably a copolymer containing 75-99.5mol% of ethylene and (B) 0.2-500 (pref. 1-200) pts.wt. of a sulfonic acid group-contg. organic compound with a molecular weight <=1,000 (e.g., benzenesulfonic acid or its lithium salt).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polymer composition comprising an ethylene copolymer and a relatively low molecular weight compound. More specifically, the present invention relates to a desired ethylene copolymer composition comprising an ethylene copolymer having a carboxylic acid group and a carboxylic acid metal base, and an organic compound having a sulfonic acid group and/or an actual compound having a sulfonic acid metal base.

The ionic ethylene-based polymer having a carboxylic acid group and a carboxylic acid metal group used in the present invention has optical properties,
It is prized for its excellent mechanical properties. 'The copolymer has various uses, and molding methods are used accordingly. The melt viscosity of the copolymer used at this time must be suitable for the molding method. Therefore, various brands have been prepared and used according to each purpose. However, in the ionic ethylene copolymer, some of the carboxylic acid groups contained in the copolymer are converted into carboxylic acid metal salts, thereby creating ionic crosslinks between polymer chains. Since it is a chemical compound, the amount of metal carpic acid varies depending on the amount of metal salt, so in order to prepare various brands, it is necessary to prepare the base copolymer with various molecular weights. However, it must be said that it is extremely disadvantageous to implement this industrially. In addition, both ionic ethylene and other polymers have a high ethylene content, so they are extremely susceptible to electrostatic charge.
Even if an antistatic agent for reflexine is added, its effect is not recognized, and this is a major hindrance in various applications.

Tokuko Publication No. 55-57265 discloses that it is a normally liquid, non-volatile compound containing at least an ionically crosslinked polymer, a functional group exhibiting a bonding moment of 6 Debye, and a solubility parameter of at least 9. A composition comprising a selective plasticizer is disclosed. In this composition, since the plasticizer is normally liquid, leaching of the plasticizer onto the surface is observed, which limits its practical use. Published Patent Publication No. 48-70757 discloses a composition that suppresses the plasticizer leaching phenomenon described above, but when the compound is stored at a high temperature and kept for a long period of time, the leaching phenomenon may be slight. may be seen. Moreover, neither of the above-mentioned two-group acid compounds exhibits an antistatic effect.

As a result of intensive study regarding the above-mentioned problems, the inventors of the present invention found that
When a relatively low molecular weight organic compound having a sulfonic acid group and/or an organic compound having a sulfonic acid metal group is blended into an ionic ethylene copolymer, the physical properties of the ionic ethylene copolymer are impaired. It has been found that the melt viscosity during molding can be lowered without any problem, and that migration, which is a major problem when using plasticizers, is extremely small. Furthermore, it was surprisingly found that the composition of the present invention has excellent antistatic properties.

Next, each component constituting the ethylene copolymer composition of the present invention will be explained.

A, ionic ethylene copolymer ethylene, α, β-ethylenically unsaturated carboxylic acid, α, β-ethylenically unsaturated carboxylic acid metal salt, and if necessary further α, β-ethylenically unsaturated carboxylic acid; It is a copolymer made by adding a saturated carboxylic acid ester.

a) α,β-ethylenically unsaturated carboxylic acids refer to monomers having 3 to 8 carbon atoms such as acrylic acid, methacrylic acid, ethacrylic acid, itaconic acid, fumaric acid, maleic acid, and monomethyl itaconate. say.

These acid monomers may be used alone in the polymer, or two or more types may be used in combination.

b) The carboxylic acids in the α,β-ethylenically unsaturated carboxylic acid metal salts are those belonging to a) above, and the metal ions include L1+, Na+, K+, 08+
“ m metal ions such as ← Oa + + , B
r+ +.

Divalent metal ions such as Ba", Ou", Zn"+,
p, 1 + + +.

Examples include trivalent metal ions such as Fe"+1. Among them, N
a+, 1g++, Oa++, zn++ ions are preferred.

C) α,β-ethylenically unsaturated carbanoic acid esters include those with an antiprime number of 4, such as methyl acrylate, ethyl acrylate, methyl methacrylate, butyl methacrylate, dimethyl fumarate, and monoethyl maleate. There are 8 monomers.

The proportions of the constituent monomers of the ionic ethylene copolymer are preferably as shown below. That is, the ethylene content is 75
~99.5 mol, preferably 85-99 mol, and the monomer having the group -<- represented by the following formula: 0.5-25 mol, preferably 1-15 mol. Among the monomers having 1a<- used here, the rate at which the carboxylic acid group and the carboxylic acid ester group age by 1 is 25 for the former.
-100 mol, preferably 40-100 mol, the latter being 0-75 mol, preferably a-60 mol.

In the carboxylic acid group, the proportion of the carboxylic acid metal base in the free carboxylic acid group and the carboxylic acid metal base is 1 molar or more, preferably 10 molar or more.

Next, a method for producing the above ethylene'-based copolymer will be exemplified.

One method is to copolymerize ethylene, α, β-ethylenically unsaturated carboxylic acid, and optionally α, β-ethylenically unsaturated carboxylic acid ester according to the method for producing high-pressure polyethylene. There is a method in which an ionic metal compound is allowed to act on the resulting copolymer. Another method is to completely or partially hydrolyze a copolymer of ethylene and α,β-ethylenically unsaturated carboxylic acid ester with an alkali, and then release a part of the metal salt of the carboxylic acid produced. There is also a method of converting it into a carboxylic acid. There is also a method in which polyethylene is graft-polymerized with an α,β-ethylenically unsaturated carboxylic acid and, if necessary, an α,β-ethylenically unsaturated carboxylic acid ester, and further treated with an ionic metal compound.

B. Compounds used in blending Organic compounds having sulfonic acid groups and their metal bases. Examples include benzenesulfone ill, p-
1 luenesulfonic acid, dodecyl bene monosulfonic acid,
Alkylbenzenesulfonic acid compounds such as octadecylbenzenesulfonic acid, 1.6-diituderopylnaphthalenesulfonic acid, 1.1! Alkylnaphthalene sulfonic acid compounds such as S-isobutylnaphthalene sulfonic acid, dodecylnaphthalene sulfonic acid, and naphthalene sulfonic acid, dialkyl sulfosuccinic acid compounds such as dioctyl sulfosuccinic acid, sodium formalin condensate of naphthalene sulfonic acid, and sulfonation of α-olefins. α-Alkenesulfonic acids, hydroxyalkanesulfonic acids, etc. obtained by
Olefin sulfonic acid compounds, fatty acid amide sulfonic acid compounds such as oleyl methyl tauric acid, polymerizable vinyl group-containing sulfones such as styrene sulfonic acid, allyl sulfonic acid, 2-ethyl sulfonate methacrylate, 2-acrylamido-2-methylpropanesulfonic acid, etc. acid compounds and lithium salts, sodium salts, potassium salts, silver salts, magnesium salts, calcium salts of sulfonic acids of the above compounds,
These are metal salts such as barium salts, zinc salts, aluminum salts, cobalt salts, manganese salts, and tin salts (the alkyl group mentioned above has 1 to 50 carbon atoms).

The amount of these compounds added is 2 to 500 parts by weight, preferably 1 to 200 parts by weight, per 100 parts by weight of the ionic ethylene copolymer.

If the amount is less than 0.2 parts by weight, the plasticizing effect and antistatic effect will be small, and if it exceeds 500 parts by weight, leaching phenomenon of the compound will be observed, which is preferable. They may be used alone or in combination of two or more.

There are various methods for mixing the compounding agent of the present invention with the ionic ethylene copolymer, but both can be mixed in a Banbury mixer.
The mixture may be mixed using a normal melt mixer such as a single-screw extruder or a twin-screw extruder, or the two may be blended during injection molding or extrusion molding to take advantage of the crosstalk effect of these molding machines. good.

Furthermore, a method may also be used in which, after adding it to an aqueous dispersion of an ionic ethylene copolymer, the water in the dispersion medium is removed by drying.

It is no problem to add additives to the composition according to the invention for the purpose of preventing thermal deterioration, preventing ultraviolet deterioration, and anti-blocking properties.

Next, examples of the present invention will be shown.

Example 1 Copolymer of ethylene and methyl methacrylate [methyl methacrylate content 5.1 mol, melting index (ASTM-D
-1258-62'1') 90, li+/1
0 minutes] was saponified using caustic soda in a mixed solvent of benzene and methanol, and all of the Methac IJJL/methyl acid in the copolymer was converted to sodium methacrylate or methacrylic acid. The saponification reaction product obtained in this manner was treated with an aqueous solution of acetic acid, and the degree of neutralization was determined! 15 ionic ethylene copolymers were obtained. The degree of neutralization referred to here is the ratio of the carboxylic acid metal base to the carboxylic acid group and the carboxylic acid metal base, and is expressed as follows.

Neutralization degree (mole) = ((aoun([:000M
] + (OOOHl))
0, 50, and 100 parts were mixed and mixed for 10 minutes at a resin temperature of 180°C using a T4 mixer. Regarding the polymer composition thus obtained, the melting index, tensile strength at break, surface resistivity, and leachability of the ingredients were measured. The leachability of the compounding agent was determined by making a sheet with a thickness of 20 mm by compression molding, leaving it in an air bath at 50° C. for one week, and then observing it with the naked eye.

The results obtained are shown in Table 1.

Comparative Example 1 The ionic ethylene copolymer used in Example 1 was measured for melting index, tensile strength at break, and surface resistivity. The results are shown in Table 1.

Comparative Example 2 Ionic ethylene copolymer 100 used in Example 1
0.1.6 parts by weight of sodium dodecylbenzenesulfonate
00 parts by weight were added and melt-mixed using a Banbury mixer. For the mixture thus obtained, the melting index, tensile strength at break, -plane resistivity, and leachability of the compounding agent were measured.

The results are shown in Table 1.

Table 1 Note (1) A8TM D 1238 Note (2) Mu STMD412 Note (3) A8TM D 257 Example 2 Copolymer of ethylene and methyl methacrylate [Contains methyl methacrylate f5.5 molar ratio, melting index (A8TMD
1258) 45.9/10 minutes] The copolymer was saponified using a caustic Sortara in a mixed solvent of xylene and isopropyl alcohol, and all of the methyl methacrylate in the copolymer was converted to sodium methacrylate or methacrylic acid. Next, the saponification reaction product obtained in this way is treated with an isopropyl alcohol solution of acetic acid, and then treated with an aqueous solution of magnesium chloride to convert sodium methacrylate into magnesium methacrylate and form ions with a degree of neutralization of 25. A polyethylene copolymer was obtained. This ionic ethylene copolymer is 100% i! 200 parts by weight of calcium dodecylbenzenesulfonate was mixed with one portion, and the mixture was mixed for 15 minutes with a resin mf160''C using a mixing roll.

- The melting index, tensile strength at break, surface resistivity, and leachability of the compounding agent were measured for the polymer composition thus obtained. The results are shown in Table 2.

Comparative example 3! The melt index, tensile strength at break, and surface resistivity of the ionic ethylene copolymer used in Example 2 were measured. The results are shown in Table 2.

Comparative Example 4 Ionic ethylene copolymer used in Example 2 1oo
Calcium dodecylbenzenesulfonate 600 in tt part
Parts by weight were added and mixed in the same manner as in Example 2 to form a composition. For this composition, the melting index, tensile strength at break,
The surface resistivity and leachability of the formulation were measured. The results are shown in Table 2.

Table 2 Example 5 Copolymer of ethylene and methyl methacrylate [Methyl methacrylate content: 5.8 mol, melt index: 45 g/10
] was saponified using caustic soda in a mixed solvent of benzene and methanol, and 40 moles of methyl methacrylate in the copolymer was converted into methacrylic acid or sodium methacrylate. Next, the saponification reaction product thus obtained was treated with an aqueous solution of acetic acid to obtain an ionic ethylene copolymer having a degree of neutralization of 354. 15 parts by weight of sodium dioctyl sulfosuccinate were mixed with 100 parts by weight of this polymer, and the mixture was kneaded and extruded using a twin-screw extruder at a resin temperature of 200°C. Regarding the polymer composition thus obtained, the melting index, tensile strength at break, surface resistivity, and leachability of the compounding agent were measured. The results are shown in Table 3.

Comparative Example 5 Regarding the ionic ethylene copolymer used in Example 5, the melting index, tensile strength at break, and surface resistivity were measured. The results are shown in Table 3.

Table 5 Example 4 70 parts by weight of octadecylbenzenesulfonic acid was mixed with 100 parts by weight of the ionic ethylene copolymer used in Example 2 in the same manner as in Example 2 to obtain a composition. The composition thus obtained was measured for melting index, tensile strength at break, surface resistivity, and leachability of the ingredients. The results are shown in Table 4.

Example 5 1.10 parts by weight of sodium oleylmethyltaurate per 100 parts by weight of the ionic ethylene copolymer used in Example 2
．． 2.0 parts by weight of each were added and melt-mixed using a Pampari mixer. The composition thus obtained was measured for melting index, tensile strength at break, surface resistivity, and leachability of the ingredients. The results are shown in Table 4.

Example 6 15 parts by weight of sodium lauryl methyl taurate were added to 100 parts by weight of the ionic ethylene copolymer used in Example 1 and melt-mixed using a Banbury mixer. The composition thus obtained was measured for melting index, tensile strength at break, surface resistivity, and leachability of the ingredients. The results are shown in Table 4.1゜Example 7 To 100 parts by weight of the ionic ethylene copolymer used in Example 3, 150 parts by weight of sodium di-1,6-itzolobylnaphthalenesulfonate was added and mixed in a Banbury mixer.
The mixture was melted and mixed using a . The composition thus obtained was measured for melting index, tensile strength at break, surface resistivity, and leachability of the compounding agent. The results are shown in Table 4.

Example 8 To 100 parts by weight of the ionic ethylene copolymer used in Example 1, 40 parts by weight of ethyl 2-sulfonate methacrylate was added and melt-mixed using a Panbury mixer.

The composition thus obtained was measured for melting index, tensile strength at break, surface resistivity, and leachability of the ingredients. The results are shown in Table 4.

Example 9 60 parts by weight of sodium 2-acrylamide-2-methylpropanesulfonate was added to a stack of 100 parts of the ionic ethylene copolymer used in Example 2, and the mixture was melt-mixed using a Banbury mixer.

The composition thus obtained was measured for melting index, tensile strength at break, surface resistivity, and leachability of the ingredients. The results are shown in Table 4.

Example 10 Ionic ethylene copolymer 1001 used in Example 3
To 1 part, 10 parts by weight of sodium dodecylbenzenesulfonate and 10 parts by weight of sodium laurylmethyltaurate were added and melt-mixed using a Banbury mixer.

The composition thus obtained was measured for melting index, tensile strength at break, surface resistivity, and leachability of the ingredients. The results are shown in Table 4.

(Itcho Yosu) Example 11 Copolymer of ethylene and methyl methacrylate [Methyl methacrylate content 7.0 mol, melt index 140 g/1
0 minutes] was saponified and neutralized in the same manner as in Example 1, all of the methyl methacrylate was converted to sodium methacrylate and methacrylic acid, and a copolymer with a neutralization degree of 35 or more was prepared. , put in an autoclave with water, 140
The mixture was stirred at ℃ for 6 hours to obtain an aqueous dispersion having a solid content concentration of 40c6. To this aqueous dispersion, 5 parts by weight of sodium oleyl methyl taurate was added to 100 parts by weight of the solid content in the aqueous dispersion, and after mixing, it was coated on a polyethylene sheet (1.0 mm thick). The coating was processed and dried to form a 4-μm thick coating. The surface resistivity of this laminate was 2.8×100 (Ω). The surface resistivity of the polyethylene sheet (1.0 mm thick) at this time is 106
(Ω) or more.

As is clear from the above description, the present invention enables molding without impairing the physical properties of the original ionic ethylene copolymer by mixing the compounding agent of the present invention into an ionically crosslinked ethylene copolymer. It is possible to change the melt viscosity of the bath at the time of use, greatly improving the moldability, and no migration of the added compounding agents is observed. Furthermore, the polymer composition of the present invention has excellent antistatic properties. As described above, the polymer composition of the present invention is extremely useful in the industrial handling of ionically crosslinked ethylene copolymers and in special applications requiring non-static properties.

Patent Applicant Asahi Tau Co., Ltd. Procedural Amendment (II Returned February 8, 1981, Japan Patent Office Commissioner Island 1) Spring Tree Membrane! , Indication of the case Patent Application No. 183053 of 1983 2 Title of the invention Copolymer composition a Person making the amendment Relationship to the case Patent applicant 1-1-2 Tun, Yurakucho, Chiyoda-ku, Tokyo Specification subject to the amendment Column 5 of “Detailed Description of the Invention” Contents of Amendment (1), page 20 of the specification, line 17 “10” was changed to “10”
” he corrected.

Written amendment to the above procedure (spontaneous) April 1982, Commissioner of the Japan Patent Office Haruki Shimada 1, Indication of the case Patent Application No. 183053, filed in 1982
No. 2 Name of the invention Copolymer composition a Relationship to the case of the person making the amendment Patent applicant 1-1-2, Tsune, Yurakucho, Chiyoda-ku, Tokyo A. Amendment to the specification subject to the amendment "Detailed Description of the Invention" Contents (1) Specification No. 6, line 19 [with sulfonic acid group and “
"Organic compound" and "Molecular weight less than 100G.

Insert "There is".

(2) 9th member, line 20 to page 10, line 1, ``Dodei benzenesulfone sodium chloride jkr)'y'' sodium siluzenesulfonate (molecule man8) J;

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Claims (1)

[Claims] A copolymer composition comprising an ionic ethylene copolymer and an organic compound having a sulfonic acid group and/or an organic compound having a sulfonic acid group