JPS63307613A - Water stopping agent for light-power cable - Google Patents

Abstract

PURPOSE:To enable a water stopping agent for light-power cables, which is excellent in the salt resistance and shows a stable water-stopping effect over a long term by using a specified polymeric cross-linking substance. CONSTITUTION:The captioned agent is comprised of a polymeric cross-linking substance, which contains not less than 0.5 mg equivalent/gram sulfonic acid group or its salt, and also contains not less than 1.0 mg equivalent/gram dissociative group. As an example of the sulfonic acid group or its salt can be given the sulfonic acid group and its metallic salt, such as sodium salt, potassium salt, calcium salt, magnesium salt, zinc salt and the like, and its organic amine salt, while, the dissociative group includes sulfonic acid group, carboxylic acid group and their metallic salt, and an anionic dissociative group, such as ammonium salt, organic amine salt, and a cationic dissociative group, such as amine, quaternary ammonium salt and the like. Thereby, a cable, which possesses a water-stopping performance being stable over a long term and an excellent durability, can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a water stop agent for optical cables and power cables. More specifically, it relates to a water-stopping agent that prevents salt water from moving inside the sheath and deteriorating the cable and various devices when highly concentrated salt water such as seawater enters the sheath of an optical/power cable. It is.

(Prior art) When a foreign wave occurs in the sheath of an optical/power cable and water infiltrates into the sheath, the water quickly moves inside the sheath and causes the problem of deterioration of the optical fiber, power line, or various devices. °. In order to solve this problem, a method has been proposed in which the inside of the sheath is filled with a water-absorbing resin.

Such water-absorbing resins are conventionally crosslinked with sodium polyacrylate, neutralized starch-acrylic acid graft polymers, saponified vinyl acetate-acrylic acid ester copolymers, and cross-linked isobutylene-maleic anhydride copolymers. Body neutralizers were used.

However, these conventional water-absorbing resins irreversibly reduce their water-absorbing ability when they come into contact with polyvalent metal ions such as calcium and magnesium, so if seawater enters the sheath or low concentrations of calcium ions from groundwater etc. There is a problem that if water that contains water penetrates for a long period of time, it will no longer exhibit its water-stopping effect.

(Problem that the invention attempts to solve) The present invention solves the above problems.

Therefore, the object of the present invention is to provide a cable with excellent salt resistance that does not reduce its water absorption capacity even when it comes into contact with concentrated salt water that has entered the sheath of an optical/power cable and exhibits a stable water-stopping effect over a long period of time. Our objective is to provide water-stopping agents for optical and power cables.

(Means and effects for solving the problems) The present invention has the following features:
sulfonating agent group or its salt at 0.5η/ff110
Contains L on D, and WIMM is 1. The present invention provides a water stop agent for optical/power cables comprising a crosslinked polymer containing 10 m or more of oryt.

The sulfonic acid group or its salt contained in the crosslinked polymer used in the present invention includes the sulfonic acid group and the sodium salt, potassium salt, calcium salt,
Metal salts such as magnesium salts and zinc salts, ammonium salts of sulfonic acid groups, and sulfonic acid groups! Examples include organic amine salts of these groups.

The dissociative groups contained in the crosslinked polymer used in the present invention include anionic dissociative groups such as sulfonic acid groups, carboxylic acid groups and their gold B salts, ammonium salts, and organic amine salts, as well as amines and cationic dissociative groups such as ammonium salts.

The polymer crosslinked material used in the present invention has a sulfonic acid group or its salt in an amount of 0.5 q equivalent m/Q or more, and a dissociable group in an amount of 1.0
It is necessary that q/m10 or more be included. The dissociative group is 1.
If it is less than 0 q equivalent/g, the water-blocking effect will not appear because the water-absorbing capacity of the crosslinked polymer will be small. Sulfone H
If the amount of the group or its salt is less than 0.5 Ml/Q, the crosslinked polymer becomes susceptible to the effects of polyvalent metal salts, and a stable water-stopping effect cannot be obtained over a long period of time.

The crosslinked polymer used in the present invention preferably has a water absorption capacity of 5 times or more of its own weight in deionized water.

If it is less than 5 times, it will be difficult to maintain a sufficient water-stopping effect for a long period of time.

Examples of crosslinked polymers effective as a water stopper for optical/power cables according to the present invention include:
A method of polymerizing the body (A) in the presence of a crosslinking agent (C) if necessary; Agent (
C) method of copolymerization in the presence of polymerizable monomer (B);
) in the presence of a crosslinking agent (C) if necessary.
A method of sulfonation with a sulfonating agent such as propane sultone or 1,4-butane sultone, ■ simultaneously reacting a linear polymer obtained by polymerizing a polymerizable monomer (B) with a crosslinking agent (C). It can be produced by a method such as sulfonation using a sulfonating agent.

Examples of the sulfone M group-containing unsaturated monomer (A) that can be used in producing the crosslinked polymer in the present invention include vinylsulfonic acid, allylsulfonic acid, methallylsulfonic acid, styrenesulfonic acid, 2-acrylamide-
2-methylpropanesulfonic acid, 3-allyloxy-2-
Hydroxypropanesulfonic acid, 2-sulfoethyl (meth)acrylate, 3-sulfopropyl (meth)acrylate, 1-sulfopropan-2-yl (meth)acrylate, 2-sulfopropyl (meth)acrylate, 1
-sulfobutan-2-yl (meth)acrylate, 2-
Unsaturated sulfonic acids such as sulfobutyl (meth)acrylate and 3°-sulfobutan-2-yl (meth)acrylate, and their alkali metal aS such as sodium and potassium
, alkaline earth metal salts such as calcium and magnesium,
Other gold ff salts such as zinc, ammonium salts, or organic amine salts may be mentioned, and one or more of these may be used.

Other polymerizable monomers (a) that can be used in the present invention (
Examples of B) include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, and citraconic acid, as well as their alkali metal salts, alkaline earth metal salts, ammonium salts, or organic amines. Carboxyl group-containing unsaturated monomers such as salts; (meth)acrylamide, (meth)acrylic nitrile, vinyl acetate, N,N-dimethylaminoethyl (meth)acrylate, 2-(methacryloyloxyethyl)trimethylammonium chloride Water-soluble unsaturated monomers such as: hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, polybutylene glycol mono(
meth)acrylate, methoxypolyethylene glycol mono(meth)acrylate, methoxypolypropylene glycol mono(meth)acrylate, methoxypolybutylene glycol mono(meth)acrylate, ethoxypolyethylene glycol mono(meth)acrylate, ethoxypolypropylene glycol mono(meth)acrylate, Ethoxypolybutylene glycol mono(meth)acrylate, methoxypolyethylene glycol/polypropylene glycol mono(meth)acrylate, phenoxypolyethylene glycol mono(meth)acrylate,
(such as benzyloxypolyethylene glycol mono(meth)acrylate, methyl(meth)acrylate, ethyl(meth)acrylate, butyl(meth)acrylate, etc.
Examples include meth)acrylic esters and hydrophobic unsaturated monomers such as styrene, and one or more of these can be used.

As the crosslinking agent (C) that can be used in the present invention,
Divinylbenzene, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate,
Propylene glycol di(meth)acrylate, polyprolene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol di(meth)acrylate, N,N-methylenebisacrylamide, Compounds having two or more ethylenically unsaturated groups in one molecule such as triallyl isocyanurate and trimethylolpropane diallyl ether: ethylene glycol, diethylene glycol, triethylene glycol,
Polyhydric alcohols such as polyethylene glycol, glycerin, polyglycerin, propylene glycol, jetanolamine, triethanolamine, polypropylene glycol, polyvinyl alcohol, pentaerythritol, sorbitol, sorbitan, glucose, mannitol, mannitan, sucrose, glucose: ethylene Glycol diglycidyl ether, glycerin diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanethiol diglycidyl ether, trimethylolpropane diglycidyl Examples include polyepoxy compounds such as ether, trimethylolpropane triglycidyl ether, and glycerin triglycidyl ether, and one or more of these can be used. When a polyhydric alcohol is used as a crosslinking agent, it is preferable to carry out the post-polymerization heat treatment at 150°C to 250°C, and when a polyepoxy compound is used, it is preferably carried out at 50°C to 250°C. Use of a crosslinking agent is preferable because the crosslinking density of the obtained crosslinked polymer can be freely controlled. The crosslinking agent is preferably used in a molar ratio of 0.00001 to 0.3 with respect to the monomer. If the molar ratio of the crosslinking agent used exceeds 0.3, the crosslinking density of the resulting crosslinked polymer tends to become too high and the water absorption capacity tends to decrease. On the other hand, if the amount is less than 0.00001, the crosslinking density is too low and stickiness occurs after absorbing water, which may cause problems in handling.

The polymerization method for obtaining a crosslinked polymer effective as a water stopper for optical/power cables according to the present invention may be any conventionally known method, such as a method using a radical polymerization catalyst, a method using a radiation/electron beam, etc.・Methods such as irradiation with ultraviolet rays etc. can be mentioned. As a radical polymerization catalyst, hydrogen peroxide,
Radical generators such as peroxides such as benzoyl peroxide and cumene hydroperoxide, azo compounds such as azobisisobutyronitrile, persulfates such as ammonium persulfate and potassium persulfate, and these together with sodium bisulfite, -7 A redox initiator in combination with a reducing agent such as scorbic acid or ferrous salt is used.

As the polymerization solvent, for example, water, methanol, ethanol, acetone, dimethylformamide, dimethyl sulfoxide and mixtures thereof can be used.

The temperature during polymerization varies depending on the type of catalyst used, but a relatively low temperature is preferable because the molecular weight of the crosslinked polymer increases. However, in order for the polymerization to be completed, it is necessary to
It is preferably within the range of ℃ or less.

There is no particular limit to the monomer concentration in the polymerization system, but considering ease of control of the polymerization reaction, yield, and economic efficiency, it is recommended to
It is preferably in the range of 0 to 80% by weight. Various forms of polymerization can be adopted, including suspension polymerization, cast polymerization, and a method in which a gel-like hydrous polymer is polymerized while being fragmented by the shearing force of a double-arm kneader (Japanese Patent Laid-Open No. 57-34101
No.) is preferred.

The water stop agent of the present invention may be used alone to fill 9 holes in the sheath of an optical/power cable, or it may be filled with asbestos, pulp, synthetic W, etc.
It may be mixed with ItH, natural fibers, etc. and filled.

Further, the water stop agent of the present invention can be used as a water stop material in a form that has good workability during filling and has a high water stop effect by combining it with lllt, rubber, plastic, nonwoven fabric, etc. Examples of these compounding methods include the following methods (1) to (4).

■By adding a water stop agent to the spinning solution of synthetic fibers, etc., or by fixing the water stop agent to a fibrous material such as synthetic fibers or natural 111rH using an adhesive substance, etc., a fibrous stop material is made. . The s+ui-shaped water stop material may be filled into the sheath as it is, or may be used after being processed into a cloth shape.

■Water-stopping agent is mixed with rubber or plastic, etc., and processed using a roll or extruder to create a sheet-like or tape-like water-stopping material.

■By fixing the water stop agent to a sheet or tape made of non-woven fabric or paper using an adhesive substance, or by sandwiching the water stop agent between sheets or tape made of non-woven fabric or paper, etc. Use as water material.

■After applying a water-stop agent mixed with an adhesive substance or paint to a plastic film, etc., cut the film as necessary to make a sheet-like or tape-like water-stop material.

(Effects of the invention) If the water stopper of the present invention is used, even if seawater or groundwater enters the sheath of an optical/power cable, water will not move inside the sheath, and stable water stoppage will be achieved over a long period of time. Cables with excellent water performance and durability can be manufactured.

(Examples) Hereinafter, the present invention will be explained in detail with reference to Examples, but the scope of the present invention is not limited only to these Examples.

Example 1 Sodium 2-sulfoethyl methacrylate J"21.6o (0,1
0 mol), methacrylic 121.5g (0.25 mol)
', Sodium methacrylate 70.2 (1 (0°65 mol), N,N-methylenebisacrylamide 0.92 (
+ (0,006 mol) and 170 g of water were charged and stirred to uniformly dissolve. After replacing with nitrogen, soak in a hot water bath for 40 minutes.
Heat to ℃ and add 1.0 g of 10% ammonium persulfate aqueous solution.
and 0.5 g of a 1% L-ascorbic acid aqueous solution were added, stirring was stopped, and polymerization was carried out. After the start of polymerization, heat was generated and 30
After a few minutes, the temperature rose to 95°C. After confirming that the temperature of the polymerization system had begun to drop, the water bath was raised to 90°C and heated for an additional hour. The water-containing glue of the obtained crosslinked polymer was finely divided, dried in a hot air dryer at 150° C. for 3 hours, and pulverized to obtain the water stop agent (1) of the present invention.

Example 2 15 ammonium 2-acrylamido-2-methylpropanesulfonate in a 500 d cylindrical separable flask
1 (0.70 mol), acrylamide 21.3G (
0.30 mol), N,N-methylenebisacrylamide 0.3 IQ (0.0'02 mol) and water 27
0 g was charged and stirred to uniformly dissolve. Thereafter, polymerization, drying, and pulverization were performed in the same manner as in Example 1 to obtain a water stop agent (2) of the present invention.

Example 3 In a 500111 fourth flask equipped with a stirrer, reflux condenser, dropping funnel, and nitrogen gas inlet tube, 22 kg of n-hexane was added.
After adding and dissolving 1.8 g of sorbitan monostearate, the mixture was purged with nitrogen.

Into the dropping funnel, add 23.3 Q (0.10 t-L) of calcium salt of 3-sulfopropyl acrylate, 1 acrylic
0.72 (1 (0.01 mol)), calcium acrylate 5.55 (1 (0.05 mol)), methacrylamide 4.
25o (0.05 mol), ethylene glycol diglycidyl ether 0.01740 (0.0001 mol), water 50 g and potassium persulfate 0.05 Ill
After adding and dissolving, nitrogen gas was blown into the aqueous solution to remove oxygen present in the aqueous solution. Next, the contents of the dropping funnel were added to the four-loaf flask and dispersed, and the temperature of the polymerization system was raised to 60 to 65% in a warm bath while introducing a slight amount of nitrogen gas.
The polymerization reaction was continued for 3 hours while maintaining the temperature at °C. Thereafter, n-hexane was distilled off under reduced pressure, and the remaining water-containing gel of the crosslinked polymer was dried under reduced pressure at 90°C to obtain a water stop agent (3) of the present invention.

Example 4 Monoethanolamine salt of 2-sulfoethyl methacrylate 51 (1
(0.2 mol), methacrylic acid 4.3Q (0.05 mol), sodium methacrylate 16.2 g (0.15 mol), methoxypolyethylene glycol monomethacrylate (containing on average 10 ethylene oxide units per molecule) ) 216° (0.4 mol), N,N-methylenebisacrylamide 0.154 (1 (0,001 mol)) and water 250a were charged and stirred to uniformly dissolve. Polymerization, drying, and pulverization were performed to obtain an uninvented water stop agent (4).

Comparative example 1 Acrylic M1 in a 500 M1 cylindrical separable flask
8a (0.25 mol), sodium acrylate 70.5
a (0.75 mol), N,N-methylenebisacrylamide 0.92a (0.006 mol), and 135 g of water were charged and stirred to uniformly dissolve them. Thereafter, polymerization, drying, and pulverization were performed in the same manner as in Example 1 to obtain a comparative water stop agent (1).

Examples 5 to 8 A glass rod with a diameter of 11 shoes and a length of 2,000 m+ was placed in a glass tube with an inner needle of 15 shoes and a length of 2,000 shoes, and a gap of 2 shoes was left between the inner wall of the glass tube and the surface of the glass rod. Ta. In this gap, the water stop agent of the present invention obtained in Examples 1 to 4 (
1) to (4) were each filled with a mixture of pulp 189 and pulp 1813 to create a simulated cable.

Hold this simulated cable horizontally, and attach Aqua Ocean (manufactured by Shinfuso Pharmaceutical @) 37. to one end of the simulated cable.
A container filled with artificial seawater obtained by dissolving 6O in deionized water to a total volume of 11 was connected, and the liquid level in the container was maintained at a height of 1000° above the simulated cable. Next, open the cock at the bottom of the container, introduce the artificial seawater into the simulated cable, and observe how the artificial seawater enters the simulated cable by measuring the distance from the end of the simulated cable to the tip where the artificial seawater has entered. evaluated. The results are shown in Table 1 along with the physical properties of the water stoppers (1) to (4) of the present invention used.

Comparative Example 2 A mock cable was created and evaluated in the same manner as in Examples 5 to 8, except that the comparative water stop agent (1) obtained in Comparative Example 1 was used as the water stop agent. The evaluation results are shown in Table 1.

Claims (1)

[Scope of Claims] 1. A stop for optical/power cables comprising a crosslinked polymer containing 0.5 mg equivalent/g or more of a sulfonic acid group or its salt and 1.0 mg equivalent/g or more of a dissociative group. Water medicine. 2. The water stop agent for optical/power cables according to claim 1, wherein the crosslinked polymer has a water absorption capacity for deionized water that is 5 times or more the weight of the crosslinked polymer. 3. The sulfonic acid group or its salt is one or more groups selected from the group consisting of sulfonic acid groups and sodium salts, potassium salts, calcium salts, magnesium salts, ammonium salts, and organic amine salts of sulfonic acid groups. A water stop agent for optical/power cables according to claim 1.