JP2012006984A - Quick curing resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a resin which cures in several tes of seconds even at a low temperature, has low irritation to skins, and exhibits a curing speed scarcely varying even by eye measuring of the volume ratio 1:1 of a two-pack liquid for repair and adhesion on emergency.SOLUTION: A oil-and-fat having a hydroxy group, a higher aliphatic acid ester having a hydroxy group or their derivative existing in the natural world, a complex salt of an oil-and-fat, a higher aliphatic acid or their derivative obtained by reacting with a halogenated boron or its ether, phenol or alcohol complex salt, and a liquid epoxy resin having a diglycidyl ether group, are allowed to react.

Description

  The present invention relates to a resin composition for curing in a short time.

A room temperature curable epoxy resin is well known as a curable resin that cures at room temperature. Bisphenol A diglycidyl ether is known as an epoxy basic resin, and amines, polyamides, mercaptans and the like are known as curing agents. Among these, it is known that the fastest curing can be expected from a combination of a tertiary amine represented by tris (dimethylaminomethyl) phenol, dimethylbenzylamine and the like and a polymercaptan curing agent. However, even if these combinations are said to be low-temperature curing and rapid curing, it takes 15 minutes to develop cured physical properties. In addition, the amine contained in the curing agent is highly irritating to the skin and may cause fogging.

  In recent years, there has been a growing demand for repairs and adhesives for fast curing, adhesives for households and DIY, emergency repairs in automobile competitions such as Formula 1, etc., emergency repairs of gas leaks and liquid leaks in factories. The present invention is not confined to conventional epoxy resins, has a pot life necessary for low-temperature curing and two-component mixing, and has a curing time of several tens of seconds, low irritation to the skin, emergency repair, and adhesion As a premise, this was achieved from the resin design in which the curing rate did not change even when the mixing ratio of the two liquids was a volume ratio of 1: 1.

The main feature of the present invention is to react an oil or fat having a hydroxyl group or a higher fatty acid ester having a hydroxyl group, a complex salt of boron halide, and a liquid epoxy resin having a diglycidyl ether group.

In the present invention, the reaction is usually carried out for several tens of seconds by cationic polymerization of a fatty acid having a hydroxyl group or a higher fatty acid ester having a hydroxyl group, a complex salt of boron halide and a liquid epoxy resin having a diglycidyl ether group at a volume ratio of 1: 1. Can be cured within.

Since the present invention uses a complex salt that can be easily obtained by adding 10% or less of a boron halide to a fatty acid having hydroxyl or a higher fatty acid ester having a hydroxyl group, the reaction with a liquid epoxy resin having a diglycidyl ether group is also used. Provides a skin-friendly material compared to the amine curing agent used.

The fast-curing resin composition of the present invention can use an oil or fat having a hydroxyl group or a fatty acid ester having a hydroxyl group or a derivative thereof existing in the natural world, and occupies about 50% of the constituent components. The effect of the present invention is great in that natural resources are used effectively.

In the present invention, the two-component system becomes cloudy during the curing process to form a two-phase system with low compatibility. Oils and fats having hydroxyl groups that become rubbery or higher fatty acid esters having hydroxyl groups or their derivative components become less compatible with the epoxy resin component during the curing process. A two-phase system is formed. At the interface of the two-phase system, the hydroxyl group and the epoxy group are chemically bonded by cationic polymerization. This is considered to be a slight decrease in the first transition point of the epoxy phase (for example,
).

Masaki Shinbo, Epoxy resin handbook, page 406

  The present inventors have found that when glass balloon or organic balloon is added as a filler, the machinability of the cured product is remarkably improved as compared with those added to existing epoxy resins. This is considered to be due to the flexibility compared with the epoxy resin. By adding a glass balloon or an organic balloon, the resin concentration in the resin composition is reduced and the curing rate is moderately slowed. Currently, for the trial production of automobiles and electrical products, foams of thermoplastic resins and thermosetting resins, extruded foam moldings, and rigid foam foams have good processability and light weight. Used as a core material for structures. However, it is difficult to correct the build-up and rework in a short time if the machine is cut too much or a machining error occurs. The repairable workable of the present invention is considered to be useful at the manufacturing site because it can be cured in a short time with a volume ratio of 1: 1 of the basis weight and a cured product with good machinability can be obtained. The present inventors have found that, compared with a workable epoxy resin, the machinability is improved by cutting wood with a canna, and in addition, the cutting surface becomes extremely fine.

In the present invention, a complex salt of a boron halide and a fatty acid having a hydroxyl group or a higher fatty acid ester having a hydroxyl group is boron trifluoride or its ether complex, a phenol complex, an alcohol complex, etc. and a fatty acid having a hydroxyl group or a higher group having a hydroxyl group. It can be easily produced by reacting with a fatty acid ester. Boron trifluoride diethyl ether, dimethyl ether, di-n-propyl ether, di-n-butyl ether and the like are used as ether complex salts of boron halides. A complex salt of boron trichloride and a fatty acid having a hydroxyl group or a higher fatty acid ester having a hydroxyl group can be obtained by mixing a dichloromethane solution of boron trichloride with a fat or a higher fatty acid ester.

Alcohol complex salts can be used as complex salts of boron halides, but substitution with fats and oils having hydroxyl groups or higher fatty acid esters having hydroxyl groups is delayed, and fats and oils having hydroxyl groups or fatty acid esters having hydroxyl groups It takes a long time to obtain the complex salt. The present inventors have found that when this property is used, a slow reactivity with the epoxy resin can be obtained. Mixing boron trifluoride methanol complex with castor oil of fat and oil with hydroxyl group slowly becomes a castor oil complex salt, and mixing with epoxy resin compared with castor oil complex salt obtained from boron trifluoride or its ether complex salt and phenol complex salt Curing slows down.

The fat or oil having a hydroxyl group is castor oil or a derivative thereof. Castor oil is an ester of higher fatty acid and glycerin, and higher fatty acid constituting castor oil is stearic acid, dioxystearic acid, oleic acid, linoleic acid, ricinoleic acid, etc., but only about 90% of ricinoleic acid having a hydroxyl group is used. % Glyceride. Usually, these higher fatty acids have a small amount of monoglyceride and diglyceride, which have a hydroxyl group. Castor oil derivatives include castor oil-based polyols, URIC H series manufactured by Ito Oil Co., Ltd., castor oil-based modified polyols containing aromatic skeleton URIC AC series, URIC PH series, castor oil hydrogenated castor oil polyoxyethylene There are additions.

As the higher fatty acid ester having a hydroxyl group, methyl ester of ricinoleic acid, butyl ester, ethylene glycol monoester, propylene glycol monoester, trimethylolpropane monoester, methyl 12-hydroxystearate and the like can be used. These boron halide complex salts are stable at room temperature.

The fat and oil having a hydroxyl group and the higher fatty acid ester having a hydroxyl group can be used singly or as a mixture of fats and oils, a mixture of higher fatty acid esters and a mixture of fats and oils and higher fatty acid esters. Generally, a boron halide complex salt of a higher fatty acid ester having a hydroxyl group cures faster with an epoxy resin than a castor oil complex salt. Therefore, a mixture with a castor oil complex salt or a mixing ratio of the epoxy resin is reduced.

As the castor oil having a hydroxyl group, castor oil derivative and higher fatty acid ester having a hydroxyl group used in the present invention, either an unsaturated compound having an unsaturated bond or a saturated compound having no unsaturated bond can be used. However, dry oils such as linseed oil, which are fats and oils with many unsaturated bonds, cannot obtain a stable complex salt with boron halide because boron halide cures the unsaturated compound itself. In addition, a complex salt of drying oil and boron halide is not practical because the curing reaction with an epoxy compound having a glycidyl ether group is too early. Similarly, semi-drying oil such as rapeseed oil has many unsaturated bonds, so that a stable complex salt with boron halide cannot be obtained.

Oils and fats are condensation compounds of fatty acids and glycerin, and usually have mono-, di-, and triglycerides, so all fats and oils have hydroxyl groups. However, the inventors have found that the most suitable oil for making stable complex salts with boron halides is castor oil. Castor oil is a glyceride containing approximately 90% of ricinoleic acid having a hydroxyl group, among the fatty acids constituting fats and oils. Ricinoleic acid has an unsaturated bond, but the hydroxyl group forms a stable complex with boron halide.

In fact, it can be confirmed from the odor that free ether or phenol is separated when castor oil is mixed with boron trifluoride ether complex or phenol complex.
Although it is well known that ethyl ether complex of boron trifluoride is stable enough to be distilled, the above fact means that castor oil forms a more stable complex than ethyl ether complex.

It is well known that boron halide has the ability to cure by cationic polymerization with an epoxy compound having a diglycidyl ether group as a Lewis acid, but the curing reaction is too early to be practical. Although monoethylamine complex salt of boron trifluoride is known as a latent curing agent, it is for high temperature curing and does not react with epoxy resin at room temperature.

The present invention uses a complex salt of boron trifluoride and a castor oil having a hydroxyl group, a castor oil derivative, and a higher fatty acid ester having a hydroxyl group, for the first time, a curing rate with an epoxy resin having a diglycidyl ether group is practical. It succeeded in controlling it.

In addition, the castor oil complex salt used in the present invention has moderate compatibility with the epoxy basic resin having a diglycidyl ether group, but since the compatibility of the castor oil component with the epoxy resin decreases during the curing process, the cured product is Forms a two-phase system (sea-island structure) of epoxy resin and castor oil. When a castor oil containing no filler, a complex salt of boron trifluoride, and an epoxy having a diglycidyl ether group are mixed, a castor oil component precipitates and becomes cloudy as the viscosity increases during the curing process.

There are limitations to the filler used in the present invention. There are no particular restrictions on the epoxy basic resin having diglycidyl ether groups, but there are carbon black and fine powder calcium carbonate for complex salts of castor oil having hydroxyl groups, castor oil derivatives, higher fatty acid esters having hydroxyl groups with boron trifluoride. Titanium oxide cannot be used. The reason for this is not clear, but it is considered that the complex salt with boron trifluoride reacts with or is adsorbed with these fillers and loses its ability as a cationic catalyst.

By using boron trifluoride and castor oil having a hydroxyl group, a castor oil derivative, a complex salt of a higher fatty acid ester having a hydroxyl group, the curing rate with an epoxy resin having a diglycidyl ether group is controlled to a practical rate, Realized fast curing resin at low temperature.
Example 1

When 7 g of boron trifluoride ethyl ether complex salt is added to 88 g of purified castor oil (hydroxyl value 161) manufactured by Toyokuni Oil and mixed, the color becomes yellowish brown and ethyl ether is liberated. This is because the ethyl ether complex of boron trifluoride was replaced with the hydroxyl group complex of castor oil. To this solution, 5 g of Aerosil (A-200) was added and mixed (Liquid B). On the other hand, 6 g of Nitto Kasei alkylene glycol diglycidyl ether eponit 028 is added to 54 g of liquid epoxy resin (Epicoat 828), 10 g of minus 350 mesh stainless steel manufactured by Fukuda Metal Foil Powder Industry, 24 g of calcium carbonate manufactured by Asahi Deposit, Aerosil 4 g of A-200 and 2 g of anti-settling agent Shiroishi Kogyo Orben L-7 were added and mixed thoroughly (Liquid A). When liquid A and liquid B are mixed at a volume ratio of 1: 1 in a total volume of approximately 20 g at 25 ° C. for approximately 20 seconds, curing begins after 20-30 seconds, and a metal sound is produced when struck with a putty knife 30 seconds after the start of curing. And completely cured. There was a slight exotherm during curing.
Example 2

When the two liquids of Example 1 were cooled to 0 ° C. and stirred, curing started 35-40 seconds later and completely cured 60 seconds after the start of curing.
There was a slight exotherm during curing.
Example 3

Liquid B is a castor oil complex salt obtained from the same ethyl ether complex salt of boron trifluoride and castor oil as in Example 1, and liquid A is 54 g of liquid epoxy resin (Epicoat 828) and alkylene glycol diglycidyl ether epoxy manufactured by Nitto Kasei. 6g of 028
And mixed. When A and B liquids were mixed in a volume ratio of 1: 1 at a total volume of about 20 g at 25 ° C. for about 20 seconds, they became transparent and became compatible, but after about 20 seconds, the mixture began to harden and became cloudy and hardened. When the cured product was struck with a putty knife, it made a metal sound and was completely cured. There was a slight exotherm during curing.
Example 4

When 9 g of boron trifluoride phenol complex salt was added to 92 g of refined castor oil (Hydroxyl value 161) manufactured by Toyokuni Oil and mixed, the color became yellowish brown and the odor of free phenol was observed. This is because the phenol complex salt of boron trifluoride was replaced with the hydroxyl group complex salt of castor oil. To this solution, 8 g of Aerosil (A-200) was added and mixed (component B). On the other hand, 8 g of EXPANSEL 092DE80d30 (copolymer of methyl methacrylate, acrylonitrile, etc.) manufactured by EXPANCEL was added to 92 g of a liquid epoxy resin (Epicoat 828) and mixed. A white putty was obtained (component A). About 20 g of A and B components were mixed by hand at a volume ratio of 1: 1. Cured in 1 minute. Cutting the cured product with a cutter knife was easier to cut than a commercially available epoxy resin workable with an organic hollow balloon, and a cut piece curved like a kanna scrap was obtained, and the cutting surface was extremely fine. .

Using a castor oil existing in nature as a raw material, an easy-to-use resin is provided that is fast-curing, has little skin irritation, and has a volume ratio of 1: 1 and volume ratio.

Claims (5)

A fast-curing resin composition obtained by reacting a fatty acid having a hydroxyl group or a complex salt of a higher fatty acid ester having a hydroxyl group and a boron halide with a liquid epoxy resin having a diglycidyl ether group. The fat or oil having a hydroxyl group or a higher fatty acid ester having a hydroxyl group according to claim 1, wherein the fat or oil is castor oil or a derivative thereof, and the higher fatty acid ester is a condensate of castor oil fatty acid or a castor oil fatty acid and an alcohol. It is a thing. The boron halide is boron trifluoride or boron trichloride, and is a complex salt obtained by reacting boron halide or an ether or phenol complex thereof with a fat or oil having a hydroxyl group or a higher fatty acid ester having a hydroxyl group. . A cured resin composition according to claims 1 to 3, wherein the cured product becomes cloudy during the curing process to form a two-phase system having an epoxy resin component and a castor oil or higher fatty acid ester component. 5. A resin composition that can be used as a workable resin, which is particularly excellent in machinability by adding a glass balloon or an organic balloon as a filler.