JPS60229904A - Electrically-conductive ethylenic copolymer - Google Patents

Abstract

PURPOSE:A copolymer moldable in a molten state into a molded article having, permanent electrical conductivity and transparency, by converting a tertiary amino group of an ethylene-tertiary amino group-containing monomer copolymer by treatment with an trialkyl phosphate into a quaternary ammonium salt. CONSTITUTION:At least part (preferably 0.5-10mol%) of tertiary amino group of an ethylene-tertiary amino group-containing monomer copolymer is treated with a trialkyl phosphate (preferably phosphate having 1-8C alkyl part) and converted into a quaternary ammonium salt, to give the desired copolymer. A copolymer obtained by copolymerizing ethylene with 0.5-20mol% based on ethylene of a compound shown by the formula I -formula III (R is H, or CH3; R' is 1-10C alkylene, or alkoxyalkylene; X is tertiary amino group) is preferable as the ethylene-tertiary amino group-containing monomer copolymer.

Description

[Detailed description of the invention] The present invention relates to a conductive ethylene copolymer.

More specifically, the present invention relates to a conductive ethylene copolymer that is easily melt-molded and has permanent chargeability and transparency.

It is well known that plastic molded products are generally easily charged with static electricity, and that various problems due to charging occur during use or processing. Conventionally, methods for preventing static electricity on these molded products have generally been taken, such as adding an antistatic agent or applying it to the surface of the molded product. Since the composition is mainly composed of a surfactant with a number of about 100 to 1000, there are problems such as the surface of the molded product becoming sticky and lack of durability of the effect.

In addition to these methods, a method of adding conductive fillers such as carbon black is also known, but with this method, a stable antistatic effect cannot be obtained unless a large amount of the filler is added, which makes molding difficult. Not only is this difficult, but the molded product is completely opaque, which limits its applications. Furthermore, in this case, there is the problem that the filler peels off from the surface of the molded product and contaminates those that come into contact with it, which is a fatal defect for applications such as packaging materials for electronic parts or molded products for transportation. Ki Naru. In particular, with the development of the electronics industry in recent years, packaging materials and transportation materials for high-density, high-precision electronic components that are extremely difficult to adhere to the seat ring due to static electricity or charging are required to maintain static electricity. Prevention and transparency are strongly required.

In addition to the methods described above, a method has also been proposed in which a copolymer obtained by copolymerizing a monomer containing a quaternary ammonium base is used as a conductive treatment agent.

For example, JP-A-53-8380 and JP-A-46-2
Publication No. 161 describes the use of this type of copolymer as a conductive treatment agent for paper, but the copolymer used here is a liquid or water-soluble solid, and cannot be molded by itself. It cannot be used as a material.

In addition, Japanese Patent Publication No. 14715/1984 proposes the use of a copolymer in which an alkyl halide is used as a quaternizing agent to form a quaternary ammonium salt. The alkyl halide used as the agent is mainly in the gaseous state, and it may cause problems such as contamination of the working environment during the reaction, and insufficient contact with the copolymer to be reacted, resulting in a smooth reaction. It is problematic and accompanies many industrial difficulties. In addition, the viscosity of the copolymer increases rapidly during this reaction, and the resulting copolymer containing a quaternary ammonium base has poor moldability and poor thermal stability, resulting in discoloration and odor. It has the disadvantage of being easy to use.

As a result of various studies in search of a conductive ethylene-based copolymer that can be easily melt-molded and molded into molded articles having permanent chargeability and transparency, the inventors found that the ethylene-h-th amino group-containing monomer It has been found that a product in which at least a part of the primary hemi/groups of a polymer copolymer is converted into a quaternary ammonium salt with a trialkyl phosphate satisfactorily satisfies these requirements. Therefore, the present invention provides a conductive ethylene-based copolymer comprising such a quaternary ammonium base-containing copolymer.
Regarding merging.

Since the conductive ethylene copolymer according to the present invention uses trialkyl phosphate as a quaternizing agent, it is not only easy to handle during the reaction, but also an ethylene-t-amino group-containing monomer. It can be brought into contact with the polymer copolymer in a molten state, and can be subjected to an industrially advantageous reaction.

1. Since deterioration of the copolymer is unlikely to occur during the reaction, when molding the obtained quaternary ammonium base-containing copolymer,
Compared to copolymers made of quaternary ammonium salts with alkyl halides, they do not cause a significant increase in viscosity and are easier to mold, and are thermally stable, so they do not cause coloring or odor in molded products. There are almost no occurrences of such occurrences, and even if they occur, the extent of such occurrences is slight, and the conductivity does not easily deteriorate.

The ethylene-tertiary amino group-containing copolymer which is converted into a quaternary ammonium salt is a copolymer of ethylene and a compound represented by the following general formula.

cH= cxaooR'x (1) OH-0ROONHR'X [1] OH-0ROOOR'X (1) Here, R is a hydrogen atom or a methyl group, and R' is an alkylene group or alkoxy having 1 to 10 carbon atoms. It is an alkylene group, and X is a tertiary amine 7 group, such as the following groups.

1s Here, h and R2 are alkyl groups having 1 to 10 carbon atoms,
It is an alkenyl group or an alkoxyalkyl group, and R3
is a hydrogen atom or an arylkyl group having 1 to 4 carbon atoms, and among these tertiary amino groups, the synthesis of a specific compound is carried out by directly copolymerizing such a comono fjt body with ethylene according to a known technique. However, generally, ethylene-(meth)acrylic acid ester copolymer is transesterified with a tertiary amine containing a hydroxyl group (copolymer with [1] above) or a tertiary amino group is transesterified. (co-ffi combination with [B] above), or an ester of a saponified ethylene-vinyl acetate copolymer and a carboxylic acid ester having 7 tertiary amine groups. According to the exchange reaction (
Copolymer with the above [11)], respectively.

In the yam group-containing monomer copolymer, the tertiary amino group-containing monomer is preferably copolymerized in a proportion of about 0.5 to 20 mol %. If the copolymerization ratio is lower than this, this is
The desired conductivity could not be obtained even when the salt was converted into a 20 mol%
This is because the synthesis of the above copolymers is difficult.

In these ethylene-tertiary amine 7 group-containing monomer copolymers, the 37th amino group @ quaternary ammonium chloride group, a trialkyl group having an alkyl group having 1 to 8 carbon atoms, or a substituted alkyl group thereof The reaction is carried out using phosphates such as trimethyl phosphate, triethyl phosphate, methyl diethyl phosphate, ethyl dimethyl phosphate).

In the quaternary chlorination reaction, trialkyl phosphate is used in a molar ratio of approximately 0.5 to 2.0 to the ^mino groups in the copolymer, and the two are brought into contact in a solution, melt, or solid state. This is done by

A particularly preferred method from an industrial perspective is a Banbury mixer.
, using a kneader-1 extruder, etc., at approximately 80 to 250°C.
, preferably in a molten state at a temperature of about 120 to 220° C. In this case, it is also effective to use a small amount of a solvent. By such a treatment method, about 0.3 to 15 mole %, preferably about 0.5 to 10 mole %, of the 9th ammonium base is introduced into the copolymer.

The structure of the quaternary ammonium salted ethylene copolymer thus obtained is as follows: FX-10 manufactured by JEOL Ltd.
Structural analysis was performed based on the results of NMR spectrum measurement and composition ratio analysis using a type 0 Fourier transform nuclear magnetic resonance apparatus.

"0-NMR spectrum: 0D with tetramethylsilane added as an internal standard sample
Measurement was performed at 50°C using OI3 solution (concentration 2%). The assignment was made with reference to the spectra of the raw material ethylene copolymer and a product obtained by transesterifying a portion of hiso with a tertiary amine containing a hydroxyl group.

54.04 ppm Carbon of methyl group bonded to quaternary nitrogen atom 64.81 ppm α-carbon of alkyl group bonded to quaternary nitrogen atom 61.89 ppm β-carbon of alkyl group bonded to quaternary nitrogen atom” P-NMR spectrum: P(OOH,)sf is used as an internal standard sample, and “O
-Measurements were made in the same manner as in the case of NMH.

Since the peaks were separated into seven peaks with a spin coupling constant of 10.5 H2, it was found that two OOH groups were bonded to phosphorus. Furthermore, chemical composition ratio analysis of Alp: Since the mole fraction of the dialkylaminoalkyl acrylate component in the NMR spectrum and the mole fraction of the phosphorus atom in the quaternary ammonium salt, which was separately measured by fluorescence XM, almost matched, Triethyl phosphate was found to exist as a counter ion to all quaternary nitrogen ions. From this, as shown in each example below, the quaternization reaction rate can be determined from K by measuring the phosphorus content.

The quaternary ammonium base-containing copolymer of the present invention whose structure is specified in this way can be easily molded into films, sheets, and other general molded products, and the molded products have transparency. The sample was left under atmospheric conditions of 25°C and 50% relative humidity for more than 2 hours, and under these conditions, the Tokyo Denshi portable high resistance meter 5TAOK was used.
(measured using TR-3 and applying an applied voltage of 10 V) is 10
It was at a level of 6 to 1012Ω, and it was confirmed that this level was constant.

Of course, the conductive ethylene copolymer according to the present invention can be used alone as a molded product, but it can also be used with at least one other resin, such as polyolefin resin, olefin copolymer resin, polyester resin, polystyrene resin, etc. It can be used as a conductive resin molding material by blending it with a resin, acetate resin, acrylic resin, methacrylic resin, AES resin, etc. or with a thermoplastic elastomer, or by laminating it with molded products thereof. In this case, the blending ratio of the conductive ethylene copolymer can be arbitrarily selected within a range of about 15% by weight or more in order to maintain desired conductivity and mechanical properties.

In particular, in order to fully express the blending effect of this copolymer, it is necessary to ensure that it is not completely compatible with the other resins to be blended (the quenched press sheet is sufficiently transparent to the naked eye in order of the thickness of the blend). It is preferable to leave the resin in a non-mineralized state, and formation of such a state can be achieved by selecting the type of other resin, blending method, conditions, etc.

Further, the conductive ethylene copolymer can also be used as a conductive treatment agent by coating it on other substrates in a liquid form such as a solution, dispersion, or emulsion, if necessary.

Conductive ethylene copolymers with these properties are
By effectively utilizing these properties, it can be effectively used in applications that require permanent conductivity and transparency, such as 10-part packaging and containers. In addition, since a hydrophilic quaternary ammonium base is introduced into the hydrophobic ethylene copolymer, the change in electrical resistance due to humidity can be used to create moisture-sensitive materials such as humidity sensors and switches. It can also be used as

Next, the present invention will be explained with reference to examples.

Example 1 Ethylene-ethyl acrylate copolymer (ethyl acrylate content: 9 mol%, melt index: 200) and dimethylaminoethanol were kneaded without a solvent.
The ethylene-
An ethyl acrylate-dimethylaminoethyl acrylate terpolymer (containing dimethylaminoethyl acrylate in m3.e mol %, melt index 30) was completely produced.

400 g of this ternary copolymer and trimethyl phosphate 707 were kneaded at 140° C. for 30 minutes under a nitrogen blanket using a kneader with a capacity of 1 t. A quaternary ammonium base-containing copolymer (melt index 5) was obtained from the measurement results of Rinjutsu Co., Ltd. using fluorescent X-rays, and the reaction rate toward tertiary amine groups was calculated to be 88%.

In this quaternary ammonium base-containing copolymer, there are 10OOH group 100002H5 group 10OOOH20H2N (OH,), a group -0OOOH2
0H2No(0Hs)3e oh 0OH3), group VC
In addition, the presence of three 10OOOH groups was confirmed as a result of NMR structural analysis, and 5
It was found that a former copolymerization chamber was formed. This is thought to be derived from the sodium methylate used as a transesterification reaction catalyst, and strictly speaking, the transesterified terpolymer must be called a quaternary copolymer.

When this five-component composite was molded into a press molding machine with a thickness of 1 fin, the surface resistivity was 3X.
Transparent f of 10'Ω! A flexible sheet was obtained using JJ.

Example 2 Example 10 180 g of the tertiary copolymer 10009 and trimethylphosphate were kneaded at 150°C using a 3010i diameter J[f[wo]. Note that trimethyl phosphate was injected into the extruder using a pressure pump. A quaternary ammonium base-containing quaternary copolymer (melt index 8) was obtained from the results of measuring the phosphorus content using fluorescent X-rays, with a reaction rate of 78% for tertiary amino groups.

This quaternary copolymer was formed into a blown film at 160° C. using a 30B diameter inflation molding machine together with 500 ppm of an additive (Sankyo Products Nord 770). A transparent, slightly brown film (thickness: 50 μm) with a surface resistivity of 5×10′Ω was obtained. This film was extracted for 4 hours in methanol at 40°C, and when the surface resistivity of the dried film was measured, a value of 8 x 10'Ω was obtained, which was not much different from before extraction. .

Example 3 Example 20 The quaternary copolymer was blended with various other resins shown in the table below, and 0.3 parts per 100 parts by weight of the blend was prepared.
After adding parts by weight of stabilizer, using a 30I diameter extruder,
The mixture was kneaded at 160-190°C.

This kneaded material was press-molded at 150 to 180°C to form a rapidly cooled press sheet with a thickness of 1 m. The surface resistivity value of this press sheet was measured and the appearance was visually observed. The results obtained are shown in the following table.

1 Low density polyethylene 50 5 x 10' (Mitsui Polychemical, ?-967) 70 1 (Mitsui Petrochemical 1.T-400) 70 8X10'4
Polymethyl methacrylate 50 6X10' (Mitsubishi Rayon, MAR) 70 2X105 ABS resin 5
0 1XIO' (East) 70 2X10"6 Styrene-methylmethac 1 route copolymer 50 2X1
0' (Tension force, RX -200) 70 2 X 10
'7 Polyamide 50 5X10 (TOSHI, OM 832x) 70 1X10's iMable polyester elastomer 50 5X10' (TOYO PUTAKUY, HTO2551) 70 2X10'Example 4 Example 204 Original copolymer 25 1 volume of water 1009
The mixture was charged into a 1100 m autoclave and heated at 140° C. for 2 hours while stirring. The copolymer was dispersed in water in a translucent state.

This aqueous dispersion was applied to a polyester film or paper in a calculated amount to give a thickness of 2 microns. A uniform coating film was formed on each of these coated surfaces at room temperature. When the surface resistivity of these coatings was measured, values of s x io'Ω for polyester film and 3 x 108 Ω for paper were obtained.

Example 5 Ethylene-vinyl acetate copolymer (vinyl acetate content 9.8
The partially saponified product (saponification degree 90%) of (mol%) was transesterified with ethyl β-diethylaminoprobionic acid,
A tertiary amino group-containing quaternary copolymer with a transesterification rate of 56% was produced.

35 g of this quaternary copolymer and 8 g of trimethyl phosphate were reacted at 160° C. for 5 minutes under a nitrogen blanket using a laboplasto mill. From the results of measuring the phosphorus content using fluorescent X-rays, a quaternary ammonium base-containing S-based copolymer with a reaction rate of 62% for tertiary amine groups was obtained, and the surface specific resistance of the sheet was calculated. When measured, it was 5×10′Ω.

Comparative Example The ternary copolymer of Example 1 was placed in a flask and dissolved in toluene, and then methyl chloride was introduced while stirring at 60° C. to convert it into a quaternary ammonium salt. After the reaction was completed, the reaction mixture was poured into a large amount of methanol, and the precipitate was separated, washed with methanol, and dried.

When the weight change curve of the resulting quaternary ammonium base-containing quaternary copolymer was measured using a thermobalance, it was found that 170
A change in the curve indicating a clear weight loss was observed at ~180°C.

On the other hand, when similar measurements were performed on the quaternary ammonium base-containing copolymer of Example 1 after washing it with methanol, the change in the weight loss curve was 2.
It appears at 20 to 230℃, and the quaternary ammonium salt formed with trimethyl phosphate is better than the quaternary ammonium salt formed with methyl chloride.
This shows that it is more thermally stable than ammonium salts.

Representative Patent Attorney Yoshi 1) Toshio Procedural Amendment (1. June 22, 1980 Patent Application No. 85711 2. Name of the invention Conductive ethylene copolymer 3. Person making the amendment Relationship to the case) Patent applicant name Mitsui Polychemical Co., Ltd. 4 Agent (105) Address 501 Ato Building, 1-2-7 Shiba Daimon, Minato-ku, Tokyo
No. 5-'m positive object (1) Page 1, line 5 (1) rCH2=CRc, 0NHR
'XJ [i'CH,=CRC:ONR'R')
Correct to LJI.

(2) In the second line of page 6, "X is" before "R' is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and" is inserted.

(3) Insert "secondary amine" after "primary amine" on page 7, line 9.

(4) "Dialkylaminoalkyl acrylate" on page 10, lines 5-6 is corrected to "acryloyloxyethyltrimethylammonium salt."

(5) Insert "In addition to the ethylene component" at the end of page 13, line 14.

(6) Delete page 13, line 15.

(7) Insert “and methanol J” after “methylate” on page 14, line 5.

(8) li'200 rroomlJ on page 14, line 5
Corrected to IIIJ.

(9) Page 18, line 10 is corrected to "Results of titration of residual tertiary amine of the washed product with P-toluenesulfonic acid and titration of tertiary amine in the base terpolymer".

Claims (1)

[Scope of Claims] 1. Electrically conductive material obtained by converting at least a part of the f-th amino group of an ethylene-tertiary amino group-containing monomer copolymer into a quaternary ammonium salt with a trialkyl phosphate. Ethylene copolymer. 2. About 0.5 to 20 mol% of tertiary amino group-containing monomer
The conductive ethylene copolymer according to claim 1, wherein the copolymer with ethylene is converted into a quaternary ammonium salt. 3. The conductive ethylene copolymer according to claim 1 or 2, wherein about 0.3 to 15 mol % of a quaternary ammonium base is introduced into the copolymer.