JPH041241A - Conductive polyurethane foam - Google Patents

Abstract

PURPOSE:To improve adhesive properties and durability and reduce the variability in conductivity by dipping a dyed flexible polyurethane foam in a treating soln. contg. a specific monomer and an oxidatively polymerizing agent. CONSTITUTION:A flexible polyurethane foam is dyed by dipping it in a dyeing bath contg. 0.001-0.2wt.% disperse dye at 80-100 deg.C. The dyed foam is dipped in a treating soln. contg. 0.01-5wt.% (based on the foam) monomer capable of forming an electronically conjugated polymer (e.g. N-methylpyrrole), a dopant (e.g. hydrogen chloride), and 1X10<-3>-1mol of an oxidatively polymerizing agent (e.g. H2O2) at -20 to 30 deg.C for 1min to 1hr and simultaneously the oxidative polymn. of the monomer is conducted, thus giving a composite material comprising the foam and the electronically conjugated polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a conductive polyurethane foam used for antistatic filling side, antistatic cushioning material for transportation packaging, sponge roll for removing static electricity, etc.

[Conventional technology]

Conventionally, conductive foams have been made by blending conductive substances such as carbon black with foams such as polyethylene, polyurethane, and synthetic rubber. There are two methods: foaming, and post-processing a conductive material mixture into a foam.

Although the former method has the advantage that a conductive foam can be obtained in the second step, the amount of conductive material added is limited due to the foaming characteristics, and the conductivity is also limited. Also,
This simultaneous foaming method has problems such as poor adhesion of the conductive substance to the foam and large variations in conductivity.

On the other hand, the latter is generally manufactured by impregnating the foam with an aqueous dispersion-based conductive treatment liquid that does not cause problems such as swelling or deterioration of the foam, and then drying it. Although the method using a liquid requires impregnation and drying steps, it is a very useful method because the resistance value can be controlled over a wide range by changing the formulation of the treatment liquid and the amount of deposit. However, in the latter method, conductive substances such as carbon black, graphite, and conductive whiskers are dispersed in water using a dispersant.
If you just prepare a conductive treatment liquid with a water-dispersible binder such as an emulsion, it is quite difficult to uniformly impregnate the foam, especially when the thickness of the foam increases.
The variation in conductivity becomes large and the performance is often unsatisfactory.

Furthermore, a method of manufacturing conductive polyurethane foam by adding a surfactant and foaming has been proposed, but this method has the problems of strong temperature dependence and poor water resistance. .

[Problem to be solved by the invention]

The present invention improves the t! The purpose of this invention is to provide a conductive polyurethane foam that improves the adhesion of a conductive material to a polyurethane foam and the variation in conductivity, and also has excellent durability.

[Means to solve the problem]

In the present invention, after dyeing flexible polyurethane foam,
The present invention provides a conductive polyurethane foam in which the flexible polyurethane foam is composited with an electronically conjugated polymer by immersing it in a treatment liquid containing a monomer capable of forming an electronically conjugated polymer and an oxidative polymerization agent.

The flexible polyurethane foam used in the present invention is made from polyhydric alcohol, polyisocyanate, and other auxiliary materials. Nats are used. polyol, catalyst,
When the foaming agent and isocyanate are mixed and poured into a predetermined location, foaming begins in a few tens of seconds and is usually completed in 60 to 300 seconds. As a gas source for foaming, there are two methods: carbon dioxide generated by the reaction between isocyanate and water is used, and low boiling point compounds such as halogenated hydrocarbons are vaporized using the reaction heat of urethanization.

Further, the flexible polyurethane foam used in the present invention preferably has a small number of closed cells, that is, a foam with many open cell structures through which the dyeing liquid and the conductive treatment liquid can easily pass. Moreover, the polyol used for the flexible polyurethane foam may be polyester-based or polyether-based, and is not particularly limited.

However, if a large amount of oxidative polymerization agent is used, in the case of a polyether type material, such as polyoxypropylene, strength may decrease due to oxidative deterioration, which is not necessarily preferable.

To dye flexible polyurethane foam, disperse dyes,
Acidic dyes, metal-containing dyes, etc. can be used, but
Acidic dyes are most preferred because of their effect on basic neutralization of terminal amino groups and urea bonds in the polyurethane foam.

Among these, disperse dyes are dyes that are insoluble in water but are dispersed in fine particles in water in the presence of a dispersant and have an affinity for flexible polyurethane foam.Most of them are azo dyes and anthraquinone dyes. Some yellow dyes include nitrodiphenylamine derivatives. Generally, they have a relatively small molecular weight structure and mostly have substituted amino groups. Also,
Specific examples of these disperse dyes include Ama, which does not contain water-soluble groups and often has nonionic hydrophilic groups such as oxyalkyl groups and cyanoalkyl groups to improve dispersibility.
cron (AAP), Ca 1 cos
p e r se (CCC), Dianix
Fast, DianixLight (Mitsubishi), Eas
tmanp(+Iyester (TE), Esteroquinone (Fran), For
on (S), Genacron (CJ), In
terchem Polydye (IC), Ka
Yalon Poyester, Laty
l (Dup), Miketon Polyester
(Mitsui), Pa1anil (BASF), Re5ol
ine (FBy), Samaron (FH),
Sumikaron (Sumitomo), Teras i 1 (
Ciba), etc.

Dyeing with disperse dyes can be carried out using a carrier dyeing method under normal pressure or a high temperature/high pressure method, but in view of the effect of the carrier on the working environment, the high temperature/high pressure method is generally used.

Further, the dye concentration of the disperse dye is preferably about 0.001 to 0.2% by weight, and the dyeing conditions are not particularly limited and may be the same as normal dyeing conditions, but if a predetermined amount is applied to the flexible polyurethane foam. Preferably, it is exhausted accurately and evenly.

Acid dyes are generally water-soluble dyes that dye animal fibers such as silk and wool, and polyamide synthetic fibers such as nylon from acid dye baths, and most belong to azo dyes, including -OH, - of naphthalene. Mainly NHz and 5O3H derivatives. With this acid dye, -NH,, -CO in animal fibers
OH etc. and dye molecules -NH2, -3o, H, -COO
It dyes by forming an electrostatic bond with the H group and has a fairly strong affinity. Furthermore, 5O3H
The 1-COOH group simultaneously serves as a water-soluble group. Examples of this acidic dye include Ac11an, 5up
racen (Bayer), Kiton, Kiton
Fast (Ciba), Pontacyl (
Dupont), Anthralan (Hochst
), Xylene, Xylene Light (Sa
ndoz), 5upranol.

5ulphon (Bayer), C1oth fast (Ciba), DuPont
Milling (DuPont), Pola r
(Geigy).

Xylene Milling (Sandoz), S
uminol (Sumitomo), Kayanol (Nippon Kayaku), Supramine (Bayer), Fulla
cid (Ciba), Er1osolid (Geigy), Aquami
ne (Sandoz), Suminol Fas
t (Sumitomo), etc.

Dyeing with acidic dyes is carried out under normal pressure at a temperature of 80 to 100° C. in an acidic environment such as acetic acid or formic acid for boat fishing.

In addition, the dye concentration of the acid dye is preferably about 0.001 to 0.2% by weight, and the dyeing conditions are not particularly limited and may be the same as normal dyeing conditions, but if a predetermined amount is applied to the flexible polyurethane foam. Preferably, it is exhausted accurately and uniformly.

Furthermore, metal-containing dyes refer to dyes that are made into metal (such as chromium) complex salts in a dye factory before dyeing, that is, dyeing is carried out with metal complex salt dyes. Therefore, it does not cause swelling or oxidative damage to wool.There are 1:1 type and 1:2 type of metal complex dyes, and both types are more sensitive to sunlight than ordinary acid dyes. It is resistant to washing, washing, perspiration, friction, etc.In order to achieve level dyeing with 1:1 type metal complex dyes, a larger amount of sulfuric acid is required than with ordinary acid dyes. If a non-ionic activator is used in combination, the amount of sulfuric acid can be reduced (equal dyeing can be obtained with half the amount of sulfuric acid).Furthermore, it is possible to use dyes according to the desired temperature. 4% by weight of sulfuric acid, 10% by weight of crystalline sodium sulfate, and 1.5% by weight of nonionic activator.
A dye bath is a common prescription. l: For type 2 metal complex dyes, the object to be dyed is pretreated in a bath containing 2-5% by weight of ammonium acetate (or 2-4% by weight of ammonium sulfate) at 50°C for 110 minutes), and then the required amount of dye is added. Add and raise the temperature until it boils.

As the second metal-containing dye, for example, Neolan (Cib
a), Palatine Fast (IC), Ult
ralan (ICI), Aizen 0pal (Hodogaya), Sumilan (Sumitomo), Irga 1an (Ge i
gy), Ciba lan (Ciba) Lanas
yn (Sandoz) Capracyl (Dupont), 0rtola
n (BASF), Lanyl (Sumitomo), l5olan
(Bayer) Kayaka fan (Nippon Kayaku) Aizen Floslan (Hodogaya), etc.

Dyeing with metal-containing dyes is done under neutral or slightly acidic conditions.
It is carried out at a temperature of ~100°C and under normal pressure.

In addition, the dye concentration of the metal-containing dye is preferably about o, ooi to 0.2% by weight, and the dyeing conditions are not particularly limited and may be the same as normal dyeing conditions, but a predetermined amount It is preferable that the gas be exhausted accurately and uniformly.

The conductive polyurethane foam of the present invention is produced by contacting a flexible polyurethane foam dyed with an acidic dye or the like with a monomer that can form an electronically conjugated polymer, and polymerizing the seven polymers in the presence of an oxidative polymerization agent. It is made by combining foam products.

A monomer capable of forming an electronically conjugated polymer is a substance that has a conjugated double bond in its molecular structure and undergoes polymerization upon oxidation.

Representative examples include 5-membered heterocyclic compounds, and examples of the 5-membered heterocyclic compounds preferably used in the present invention include virol, thiophene, furan, indole, and derivatives thereof, such as N-methylpyrrole, 3-methylpyrrole, 3-methylthiophene,
These include, but are not limited to, 3-methylfuran and 3-methylindole.

These heptamers are polymerized by contacting them with an oxidative polymerization agent, preferably in the presence of a dopant. Also,
The concentration of these monomers is 0.01 to 5% by weight per flexible polyurethane foam, depending on the concentration of conductivity to be imparted.
is preferred.

As this dopant, all commonly used acceptor dopants can be used.

Acceptor dopants include halogens such as chlorine, bromine, and iodine; Lewis acids such as phosphorus chloride; protonic acids such as hydrogen chloride and sulfuric acid; transition metal chlorides such as ferric chloride; silver perchlorate. , transition metal compounds such as silver boron fluoride, and the like.

In addition, examples of oxidative polymerization agents include permanganic acid or permanganic acids (salts); chromic acids such as chromium trioxide;
Nitrates such as silver nitrate; Halogens such as chlorine, bromine, and iodine; Oxides such as hydrogen peroxide and hendiyl peroxide; Beroxo acids and peroxo acid salts such as Beroxonisulfuric acid and Potassium Beroxonisulfate; hypochlorous acid, Oxygen acids and acid salts such as potassium hypochlorite and potassium hypochlorite; ferric chloride, cupric chloride, tin chloride,
Examples include transition metal chlorides such as potassium chloride; metal oxides such as silver oxide. Among these oxidative polymerization agents, halogens, peroxo acids (salts), transition metal chlorides, etc. act as dopants, so when they are used as oxidative polymerization agents, they are especially sensitive to other dopants. Although it is not necessary to use them together, the conductivity can be further improved when used together with a dopant. In addition, as other oxidative polymerization agents, for example, ammonium persulfate, potassium persulfate, sodium persulfate, cupric perchlorate, ferric perchlorate, etc. can be used, and these can be used alone or in combination.

The amount of the oxidative polymerization agent to be used is preferably about 2 to 3 moles, particularly about 2 moles, relative to the monomer capable of forming the electronically conjugated polymer.

In the present invention, a flexible polyurethane foam dyed with an acid dye or the like is immersed in the treatment liquid, and a monomer capable of forming an electronically conjugated polymer is brought into contact with an oxidative polymerization agent in the treatment liquid.

As a method for treating flexible polyurethane foam with a treatment liquid, for example, 1) immersing the flexible polyurethane foam in a treatment liquid containing a monomer, an oxidative polymerization agent, and, if necessary, a dopant, before the polymer is substantially polymerized. Method, ■ A method of sequentially immersing flexible polyurethane foam in a treatment solution containing an oxidative polymerization agent and a dopant as necessary, and a treatment solution containing a monomer, ■ A treatment solution containing an oxidation polymerization agent and a dopant as necessary Examples include a method in which a flexible polyurethane foam is immersed in a solution, and then nanatsuma is added to the treatment solution.

According to method (2), processing time can be shortened. In addition, since the oxidative polymerization agent has a lower permeability into flexible polyurethane foam than the seven-layered foam, treatment with a monomer-containing treatment solution and immersion treatment with a treatment solution containing an oxidation polymerization agent are performed as in methods ① and ②. It is preferable to adopt a separate method and perform the immersion treatment with a treatment solution containing an oxidative polymerization agent first.In this way, the amount of oxidation polymerization agent impregnated into the flexible polyurethane foam increases, so the electronic conjugated polymer and the soft Composite formation with polyurethane foam is promoted, resulting in better and more durable electrical conductivity.

When the monomers and oxidative polymerization agents that can form these electronically conjugated polymers are liquid, they can be used as they are as the treatment liquid. In the method of immersing flexible polyurethane foam in a treatment solution mixed with an oxidative polymerization agent, polymer formation in the treatment solution is rapid, preventing the formation of a composite between the flexible polyurethane foam and the polymer, and ensuring sufficient conductivity. Because there is a risk that you may not be able to obtain
It is preferable to use the monomer and oxidative polymerization agent after diluting them with a suitable solvent.

As this solvent, water or a commonly used organic solvent can be used. Examples of the organic solvent include methanol, ethanol, n-propanol, i-probanol, and t-propanol.
- Aliphatic alcohols such as butyl alcohol and i-butyl alcohol; Aliphatic ketones such as acetone, methyl ethyl ketone, and cyclohexanone; Ethers such as diethyl ether, tetrahydrofuran, and dioxane;
Halogenated hydrocarbons such as methylene chloride and chloroform; Esters such as ethyl acetate and butyl acetate; Aromatic hydrocarbons such as toluene and benzene; Aliphatic hydrocarbons such as hexane; Nitrogen-containing such as acetonitrile and benzonitrile compounds or mixtures thereof,
A suitable solvent is selected from among these solvents depending on the 7-mer dopant, oxidative polymerization agent and flexible polyurethane foam.

The monomer concentration and oxidative polymerization agent concentration in the treatment solution vary depending on the material of the flexible polyurethane foam and the desired degree of conductivity, but the monomer concentration is preferably about 5×10-” to 1 molar concentration, and the oxidation polymerization agent concentration is The polymerization agent concentration is I
It is preferable to set it to approximately X 10-' to emollient concentration.

Note that the monomer concentration is preferably about 0.01 to 5% by weight per flexible polyurethane foam.

Moreover, the dopant concentration is I x 10-' to 1 x 10
-2 molar concentration is preferred.

The temperature of the treatment liquid when immersing the flexible polyurethane foam in the treatment liquid is -2 to further improve the given conductivity.
The temperature is preferably 0 to 30°C, particularly preferably 20 to 5°C.

The immersion time for the flexible polyurethane foam varies depending on the material of the flexible polyurethane foam and the desired degree of conductivity, but is usually about 1 minute to 1 hour.

Note that the production reaction of electronically conjugated polymers such as polypyrrole proceeds in an acidic solution, and the polymerization product that has lost solubility in the solvent due to the polymerization reaction deposits and adheres to the nearby solid surface. The oily substances that adhere to or coexist in the polyurethane foam that act as adhesion inhibiting factors and the basic substances that act as acidity inhibiting factors, such as foam stabilizers, surfactants, chain extenders, catalysts, and antioxidants in polyurethane foam, are It is preferable to wash and remove it before dyeing in order to obtain uniform conductivity.

Here, silicone oil is used as a foam stabilizer, and polyoxyethylene, alkyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene polyoxypropylene block copolymer, etc. are used as surfactants.
Chain extenders include monoethanolamine, jetanolamine, N-ethyl jetanolamine, N-methyl jetanolamine, diethylene glycol, dipropylene glycol, ethylene glycol, propylene glycol, 1.4-butanediol, 1.3-butane. Examples include low molecular weight compounds such as diol, neopentyl glycol, and 3-methylbentanediol.

Furthermore, examples of urethane foam polymerization catalysts include triethylenediamine, N-ethylmorpholine, N-methylmorpholine, 2-ethyl-4-methylimidazole, tetramethylhexamethylenediamine, pentamethyldiethylenetriamine, 1,8-diazabicyclo( 5,
4,O) undecene-7, as an antioxidant, for example, 2,6-di-t-7'thyl-4-hydroxy-toluene (
BHT), octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)-propionate (such as Irganox 1076), pentaerythrityl-tetrakis (3-(3,5-di-t-butyl-4-hydroxyphenyl)-propionate), phenyl)-probionate] (Irganox 101
0, etc.).

As this washing removal means, prior to the dyeing, the flexible polyurethane foam is washed with polyoxyethylene nonylphenyl ether, sodium lauryl sulfate, sodium alkyl dodecylbenzenesulfonate, coconut oil fatty acid, etc., which are commonly used for cleaning oils and fats. jetanolamide,
1-5 g/! of surfactants such as alkyl alkylolamides and alkyl ether sulfate sodium salts! Examples include washing with an aqueous solution at a liquid temperature of 40 to 60°C for 5 to 30 minutes.

[Effect]

To produce the conductive polyurethane foam of the present invention, first, a flexible polyurethane foam is dyed with an acid dye or the like.

Thereafter, this dyed flexible polyurethane foam is immersed in a treatment solution containing a monomer capable of forming an electronically conjugated polymer and an oxidative polymerization agent, thereby compounding the electronically conjugated polymer onto the flexible polyurethane foam.

By doing this, the monomer is easily adsorbed to the flexible polyurethane foam, which has been dyed with an acid dye or the like and has a loose microstructure, and by polymerizing the monomer, it becomes a flexible polyurethane foam. When combined with a polymer, a durable conductive polyurethane foam is obtained.

[Examples] Examples of the present invention will be described in detail below.
The invention is not limited to these examples.

Example I PPG polyurethane foam (density 20 g/f) was filled into the cheese dyeing machine carrier without any gaps, and after washing on the nonionic refining side (3 g/f) at 60°C for 30 minutes to remove oil etc. The drain was washed until it stopped bubbling.

Next, Acidol Green
) M-FGL 1% owf and ammonium sulfate 5% owf
Incubate the dye solution containing wf at 98-100°C for 60 minutes.
alternately circulated out-in (inout-in),
After cooling, it was thoroughly washed with water and further washed with ion-exchanged water.

Next, a conductive treatment liquid containing 1% owf of pyrrole monomer, 3 mol of ferric chloride per 1 mol of pyromonomer, and 10% by weight of isopropyl alcohol was maintained at a liquid temperature of 7°C.
After circulating at 1 n-out-in for 240 minutes, the sample was thoroughly washed with water and dried at 60°C under reduced pressure.

The surface resistance value of the obtained conductive polyurethane foam was 1
06Ω, light resistance test (black panel temperature 63°
After performing C) for 50 hours, the surface resistance value was 1.7X10
'Ω was.

Example 2 Polyester urethane foam (density 22 g/liter) was filled into a cheese dyeing machine carrier without any gaps in the same manner as in Example 1, and thoroughly washed.

Next, it was dyed with Kayalon Polyester Blue T-32% owf at 130°C for 60 minutes, thoroughly washed with water, and then further washed with ion-exchanged water.

Thereafter, an aqueous solvent solution containing 1.5% owf of pyrrole monomer, 3 mol of ferric chloride per 1 mol of pyrrole monomer, and 10% by weight of isopropyl alcohol was added.
After circulating the solution for 240 minutes while maintaining the liquid temperature at 7°C in an n-out-in mode, it was thoroughly washed with water and dried at 60°C under reduced pressure.

The surface resistance value of the obtained conductive polyurethane foam was 3
x10'Ω, light resistance test (black panel temperature 6
After 50 hours at 3°C, the surface resistance was 1.8X.
It was 10'Ω.

Comparative Example 1 The same polyurethane foam as in Example 1 was thoroughly washed, and an aqueous solvent solution of a pyrrole monomer and an oxidative polymerization agent was circulated in a cheese dyeing machine for 240 minutes in the same manner as in Example 1 without going through the dyeing process. Ta.

After drying, the surface resistance value of the obtained conductive polyurethane foam was 107Ω, and the surface resistance value after conducting a light resistance test (black panel temperature 63°C) for 50 hours was 2X.
It was 10'Ω or more, and there was no adhesiveness between the polyurethane foam and polypyrrole.

〔Effect of the invention〕

In the present invention, after dyeing a flexible polyurethane foam, the flexible polyurethane foam is immersed in a treatment solution containing a monomer capable of forming an electronically conjugated polymer and an oxidative polymerization agent to composite the electronically conjugated polymer into the flexible polyurethane foam. Since it is a conductive polyurethane foam made of polyurethane foam, it is possible to obtain a conductive polyurethane foam that improves the adhesion of the conductive material to the polyurethane foam and the variation in conductivity, and also has excellent durability.

Patent applicant: Achilles Corporation Agent Patent Attorney Takashi Shirai

Claims (1)

[Claims] (1) A conductive material obtained by dyeing a flexible polyurethane foam and then immersing it in a treatment solution containing a monomer capable of forming an electronically conjugated polymer and an oxidative polymerization agent to combine the electronically conjugated polymer with the flexible polyurethane foam. polyurethane foam.