JPS6314010B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a method for producing an epoxy resin curable composition imparted with latent curability by using a mixed curing catalyst.

(Conventional technology) There are two methods for curing epoxy resin: heating and curing a resin system (one-component resin) in which BF ₃ complex, dicyandiamide, etc. are mixed with the epoxy resin in advance; There is a method in which a relatively highly active copolymer component (curing agent) and an epoxy resin component are stored separately in advance, and mixed and cured (two-component resin) at the time of use.

(Problems to be solved by the invention) Of these, BF ₃ is used for one-component epoxy resin.
Although complexes and dicyandiamide are known as latent curing agents with good storage safety at low temperatures, they have an adverse effect on the electrical and mechanical properties of cured products at high temperatures.

Furthermore, when polyamine is used as a curing agent, there are operational problems such as skin irritation, and it is difficult to obtain a cured product with good heat resistance. Even when acid anhydrides are used as hardening agents, the acid anhydrides themselves are volatile, which causes problems such as producing a bad odor during work and irritating clothes, as well as easily producing free carboxylic acids due to moisture absorption. Has a point.

Recently, there have been attempts to use epoxy resins in reaction injection molding, but in this case, long-term storage safety is required, while the development of highly active catalysts that can instantly cure during molding is required. It was considered an urgent task.

The present invention has an extremely long shelf life when stored as a two-component type, and can be quickly cured by mixing or blending, making it suitable for applications such as adhesion, molding, impregnation, and casting. The object is to provide a composition.

[Structure of the Invention] (Means for Solving the Problem) In view of the above points, the present inventors have carried out intensive studies and have found that, as a curing catalyst system for epoxy resin, it alone has no activity for polymerizing epoxy resin. At least one type of organosilane or organosiloxane compound having almost no silanol group or halogen or alkoxyl group bonded to Si, and aluminum β which is also known to have extremely low activity as a curing catalyst for epoxy resin. Focusing on the fact that it becomes a highly active catalyst when combined with at least one of diketone, acetoacetate, and orthocarbonylphenol compounds, we developed a completely different type of catalyst from the conventional epoxy resin-copolymerization component (curing agent) system. It has been found that a reactive two-component epoxy resin system can be obtained. That is, the present invention provides at least one organosilicon compound selected from organosilane or organosiloxane compounds having a silanol group or a halogen or alkoxyl group directly bonded to a silicon atom, and a bisphenol type epoxy resin,
Alicyclic epoxy resin, heterocyclic epoxy resin,
and at least one epoxy resin selected from aliphatic epoxy resins.
and (b) at least one aluminum compound selected from aluminum β diketone, acetoacetate, and orthocarbonyl phenol compound, bisphenol type epoxy resin, alicyclic epoxy resin, polycyclic epoxy resin, and a second component contained in at least one epoxy resin selected from aliphatic epoxy resins.

Therefore, the organosilicon compound in this first component is usually 100 parts by weight of the epoxy resin component.
It is sufficient to contain it in a range of 0.001 parts by weight to 5 parts by weight. In addition, the composition ratio of the aluminum compound in the second component is 100% of the epoxy resin component.
It is sufficient to select about 0.001 parts by weight to 5 parts by weight based on the weight.

In the present invention, examples of epoxy resins that can be used and are the main component include the following. Namely, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, alicyclic epoxy resin, heterocyclic epoxy resin such as triglycidyl isocyanate and hydantoin epoxy, Hydrogenated bisphenol A type epoxy resin, aliphatic epoxy resin such as propylene glycol-dicrydyl ether and bentaerythritol-bolyglycidyl ether, and reaction of aromatic, aliphatic or alicyclic carboxylic acid with epichlorohydrin. The resulting epoxy resin, spiro ring-containing epoxy resin, glycidyl ether type epoxy resin which is a reaction product of an ortho-allyl-phenol novolak compound and epichlorohydrin, and diallyl having an allyl group at the ortho position of each hydroxyl group of bisphenol A These include glycidyl ether type epoxy resin, which is a reaction product of a bisphenol compound and epichlorohydrin.

These epoxy resins may be used alone or as a mixture of two or more.

(Function) In the composition according to the present invention, the epoxy resin is presumed to generate polyether through ring-opening polymerization, and is sufficiently cured without particularly adding other copolymerization components (generally called curing agents). However, it is also possible to use epoxy resin comonomers such as acid anhydrides, isocyanate compounds, phenol compounds, amine compounds, and alcohol compounds, if necessary.

In addition, the epoxy resin composition of the present invention is a so-called solvent-free resin whose viscosity and curing temperature vary depending on the selection of resin components, and can be used for adhesives, casting, impregnation, molding, etc. ranging from room temperature curing type to high temperature curing type. Can be used. Furthermore, since it is easily dissolved in low-boiling point solvents such as dioxane, tetrahydrofuran, and methyl ethyl ketone, it can be used as solvent-based paints, adhesives, and insulating varnishes. Moreover, the epoxy resin composition according to the present invention has excellent curability, and the cured resin exhibits excellent heat resistance, mechanical properties, and electrical insulation properties. Thus, the resin composition of the present invention can be said to be a material that has good workability and can be used for a wide range of purposes.

Next, examples of the present invention will be described.

(Examples) Example 1 1 g of aluminum trisacetylacetonate was added to 100 g of an alicyclic epoxy resin (Chitsonox 221; Chitso Corporation, trade name) and heated to 80° C. to obtain a uniform resin (liquid A). On the other hand, 100g of the same kind of epoxy resin was collected separately, and 2 pieces of silicone resin (SH6018; Toray Silicone, trade name) was collected here.
g was added, and the mixture was heated and dissolved to obtain a uniform resin (liquid B). These solutions A and B showed no increase in viscosity even after being left at room temperature for 30 days. Next, an epoxy resin composition was prepared by mixing the liquid A and liquid B at room temperature. In this resin composition, the organoaluminum compound component and the silicone component reacted rapidly, turning pale pink and rapidly curing.

Example 2 Alicyclic epoxy resin (Titsonox 221) 50
g to aluminum trisacetylacetonate 1
g was added and uniformly heated and dissolved to obtain Solution A. Also, hydroxyl group-containing silicone resin (SH6018)
2g, alicyclic epoxy resin (Titsonox 221)
40 g of bisphenol A type epoxy resin (Epicoat 1001; trade name, Ciel Co., Ltd.) were mixed under heat to obtain a uniform B solution. Next, the above liquids A and B were mixed to produce a resin composition. The thus obtained resin composition was applied to an iron test piece (25 x 1 x 120 mm) whose surface had been previously polished with sandpaper (No. 240).
mm) Apply to two sheets so that the adhesive area is 3 cm ² ,
The adhesive was held between clips and left at room temperature for 15 hours, and the tensile shear adhesive strength was measured at a tensile rate of 1 mm/min. The adhesive strength was 95 kg/cm ² at 25°C. The epoxy resin composition according to the present invention has performance as a room temperature curing epoxy adhesive that can replace the highly toxic amine curing type.

Example 3 Alicyclic epoxy resin (Titsonox 221) 40
g, 2 g of aluminum trisacetylacetonate was heated and dissolved in 10 g of bisphenol A type epoxy resin (Epicote 1001) to obtain Solution A. In addition, 2 g of a hydroxyl group-containing silicone resin (SH6018) was heated and dissolved in 50 g of the same epoxy resin to obtain liquid B. Next, as in Example 2, liquid A was applied thinly to one of the iron test pieces, and liquid B was applied thinly to the other test piece. 2 where the above liquids A and B were applied respectively.
The two test pieces were held together with clips, mixed in this state, allowed to stand at room temperature for 3 hours, and then cured in an oven at 50°C for 4 hours. The tensile shear adhesive strength of the adhesive test piece thus obtained at 25°C was 145
It was Kg/ ^cm2 .

Comparative Example 1 Bisphenol A liquid was mixed with epoxy resin (Escort 828; Ciel Co., Ltd., trade name) and aliphatic amine curing agent Epomate (Ajinomoto Co., Ltd., trade name) Example 3
Similarly, after coating two iron test pieces separately, they were sandwiched between paper clips and placed in an oven (50°C) for 3 hours at room temperature.
Although the test piece was heated for 4 hours at a temperature of 30°F (°C), the adhesive strength was weak and the test piece peeled off when the clip was removed.

Example 4 Bisphenol A liquid epoxy resin (Ebicoat
1001), 20 g (Ebicoat 828), and 1 g of aluminum trisacetylacetonate were dissolved in 100 g of methyl ethyl ketone. This solution showed almost no increase in viscosity even after 30 days. On the other hand, 20 g of Ebicoat 1001 and 3 g of hydroxyl group-containing silicone resin (SH6018) were dissolved in 100 g of methyl ethyl ketone. This solution also showed no change in viscosity even after 30 days had passed.

Next, both solutions were mixed at a ratio of 1:1 to prepare an epoxy resin composition solution. This solution was poured onto an aluminum plate (100 x 150 x 1 mm) and cured at 180°C for 10 minutes, which was repeated three times.
A homogeneous coating was obtained. The volume resistivity of this coating film at 150° C. was 3.6×10 ¹³ Ω.cm, and tan δ was 4.6%.

Example 5 Bisphenol F type epoxy resin (Epicron
830; Dainippon Ink, trade name), 200 g of crystalline silica was added to 200 g, mixed uniformly, and then divided into two parts. An alkoxysilane compound (epoxysilane A-
187; UCC Company, trade name), and 1 g of aluminum trisacetylacetonate was added to the other divided resin system and dissolved by heating to obtain a two-component casting resin. Next, the composition prepared by mixing these two components was poured into a mold and heated at 160°C for 3 hours at 120°C.
After curing for 15 hours, test pieces for measuring bending strength (60
x 2 x 10 mm). The bending strength of this test piece at room temperature is 16.2Kg/mm, and at 100℃ it is 6.5Kg/mm.
It was warm in mm.

[Effects of the Invention] As described above, according to the present invention, it exhibits a long shelf life when stored as a two-component type, and quickly hardens when mixed or blended. An epoxy resin curable composition can be obtained.

Claims (1)

[Scope of Claims] 1 a At least one organosilicon compound selected from organosilanes or organosiloxane compounds having a silanol group or a halogen or alkoxyl group directly bonded to a silicon atom is combined with a bisphenol type epoxy a first component contained in at least one epoxy resin selected from among resins, alicyclic epoxy resins, heterocyclic epoxy resins, and aliphatic epoxy resins; b aluminum β diketone, acetoacetate; and at least one aluminum compound selected from orthocarbonylphenol compounds, and at least one aluminum compound selected from bisphenol type epoxy resins, alicyclic epoxy resins, heterocyclic epoxy resins, and aliphatic epoxy resins. A method for producing an epoxy resin curable composition, comprising blending a second component contained in a seed epoxy resin.