KR20160060480A - Adhesive composition for structure, and preparing method thereof - Google Patents

Abstract

The present invention relates to an adhesive composition for structures and a method for producing the adhesive composition for the structures. According to the present invention, the adhesive composition can be used even in a laser-welded portion. To this end, the composition includes an epoxy resin, a filler, a hardening agent, and a catalyst.

Description

TECHNICAL FIELD [0001] The present invention relates to a structural adhesive composition and a method for producing the same,

The present invention relates to a structural adhesive composition, and a process for producing the structural adhesive composition.

Structural adhesives are a good alternative to other mechanical techniques for joining two materials together, such as metal or plastic. These structural adhesives are good alternatives to mechanical techniques such as rivet tightening or welding, where two different materials are bonded together. This is because when the structural adhesive is used, the stress is uniformly distributed and the force is dispersed, so that a more excellent effect than the mechanical technique can be obtained. In addition, when a structural adhesive is used, it is possible to bond different kinds of materials, lighten weight, airtightness and watertightness, and improve the working speed quickly. It also has the advantage of better distribution of force in adhesive bonding than using alternative technologies such as betting or welding and provides higher insulation against external factors such as dust or moisture than mechanical techniques. Due to these various advantages, the structural adhesive is used in various industrial fields.

The structural adhesive consists of two components, a resin comprising a monomer and a catalyzed component used to effect polymerization of the other component. Therefore, there are three types of two-component adhesives (epoxy, polyurethane, and acrylic) depending on the properties of the monomers present in the resin. There is a possibility that acrylic adhesives can be used on the surface, especially with the polymerization profile and not in advance. However, there is a disadvantage that the result of the adhesive bonding of the acrylic adhesive and the composite materials is inferior in performance to that obtained by using an epoxidized adhesive, especially in the case of a composite made from an airtight mold.

Korean Patent Laid-Open No. 10-2012-0112447 relates to a structural epoxy resin adhesive containing an elastomeric toughening agent encapsulated with a ketoxime, which comprises at least one epoxy resin; At least one reactive elastomeric toughening agent having capped isocyanate groups; And at least one epoxy curing agent, wherein at least 90% of the capped isocyanate groups of the reactive toughening agent in the structural adhesive are capped with a ketoxime compound.

Accordingly, the present invention provides a structural bonding composition and a method for producing the structural bonding composition.

However, the problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

One aspect of the present invention provides a structural adhesive composition comprising an epoxy resin, a filler, a curing agent, and a catalyst.

Another aspect of the present invention provides a method for producing a structural adhesive composition, comprising mixing an epoxy resin with a filler and a resin reinforcement, and then adding a curing agent and a catalyst to react to obtain a structural adhesive composition.

Another aspect of the present invention provides a structural adhesive comprising the structural adhesive composition according to the above aspect.

According to any one of the above-mentioned means for solving the problems, a tape-type or paste-type structural adhesive can be used for laser welding. In addition, it can be used for a part that can not be operated by a robot. In the process of using the robot, environment-friendly construction method is used.

According to any one of the above-mentioned means for solving the problems, the tensile strength and the peel strength can be improved by about 50% or more as compared with the conventional structural adhesive.

According to any one of the above-mentioned means for solving the problems, it is possible to exhibit effects such as adhesion strength, air tightness, noise reduction and the like in preparation for single spot welding in combination with structural adhesive bonding to existing spot welding portions, It is possible to join or double-bond the material of the non-weldable material such as aluminum.

According to any one of the above-mentioned means for solving the problems, it is possible to adhere to an adherend such as a metal or steel having a high thermal expansion coefficient with a high peel strength.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. It should be understood, however, that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, the same reference numbers are used throughout the specification to refer to the same or like parts.

Throughout this specification, when a part is referred to as being "connected" to another part, it is not limited to a case where it is "directly connected" but also includes the case where it is "electrically connected" do.

Throughout this specification, when a member is "on " another member, it includes not only when the member is in contact with the other member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without departing from the other elements unless specifically stated otherwise.

The terms "about "," substantially ", etc. used to the extent that they are used throughout the specification are intended to be taken to mean the approximation of the manufacturing and material tolerances inherent in the stated sense, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure.

The word " step (or step) "or" step "used to the extent that it is used throughout the specification does not mean" step for.

Throughout this specification, the term "combination (s) thereof " included in the expression of the machine form means a mixture or combination of one or more elements selected from the group consisting of the constituents described in the expression of the form of a marker, Quot; means at least one selected from the group consisting of the above-mentioned elements.

Throughout this specification, the description of "A and / or B" means "A or B, or A and B".

Hereinafter, embodiments of the present invention are described in detail, but the present invention is not limited thereto.

One aspect of the present invention provides a structural adhesive composition comprising an epoxy resin, a filler, a curing agent, and a catalyst.

In one embodiment herein, the structural bonding composition comprises from about 60 to about 95 parts by weight of an epoxy resin, from about 2.7 to about 15 parts by weight of a filler, from about 5 to about 10 parts by weight of a curing agent, and from about 0.2 to about 4 parts by weight of a catalyst But the present invention is not limited thereto.

In one embodiment of the invention, it may include, but is not limited to, additional resin reinforcements.

In one embodiment of the present invention, the resin reinforcement may be included in an amount of about 2 to about 20 parts by weight, but may not be limited thereto.

In one embodiment of the invention, the epoxy resin may comprise a modified epoxy resin, for example, selected from the group consisting of bisphenol A type epoxy resins, polyether modified epoxy resins, and combinations thereof But may not be limited thereto. For example, the polyether-modified epoxy resin may include, but is not limited to, an amine-modified epoxy resin.

In one embodiment herein, the epoxy equivalent (EEW) of the epoxy resin may be from about 100 to about 1,000, but is not limited thereto. The epoxy equivalent is an equivalent per one epoxy group (g / eqiv.) And is an average molecular weight divided by the number of epoxy groups per molecule.

In one embodiment of the present invention, the polyether epoxy resin may be a polyether bonded to an epoxy main chain using an epoxy functional group of a bisphenol A type epoxy resin, and an amine group is substituted for an epoxy resin terminal group. . When the terminal group of the epoxy resin is reacted with an amine, the terminal group is substituted with an amine, and the epoxy group site is substituted with an amine to be substituted with an -OH group. The epoxy resin is partially substituted, and may be substituted with about 5% to about 30% of the epoxy equivalent, but the present invention is not limited thereto.

In one embodiment of the present invention, the epoxy resin used in the structural bonding composition may be an intermediate obtained by mixing the two epoxy resins, and adding functional epoxy resin or intermediate for improving peel strength and impact strength , But may not be limited thereto.

In one embodiment of the present invention, the resin reinforcements may include, but are not limited to, those selected from the group consisting of coupling agents, moisture absorbers, dispersants, and combinations thereof. For example, it may include, but is not limited to, using the resin reinforcement to lower the viscosity dependency of the worker depending on the work environment and environmental factors. When the resin reinforcement is added, peel strength, viscosity, and shape retention are improved, and flexibility can be increased.

In one embodiment of the invention, the filler may comprise, but is not limited to, selected from the group consisting of coated carbon black, coated calcium carbonate, silica, and combinations thereof.

The filler is a filler added for property enhancement, cost reduction, viscosity control, flow control, or color imparting.

The carbon black may be added for imparting hue and conductivity, and may include, but is not limited to, hydrophobicity by surface treatment to improve storage stability, water resistance and durability. For example, the carbon black may be classified into a contact black, a furnace black, a thermal black, or a lamp black according to a manufacturing method, and may be classified into gas black, oil furnace black, naphthalene black, anthracene black, acetylene black, Black, and vegetable black, but the present invention is not limited thereto. In one embodiment of the invention, the structural bonding composition may include, but is not limited to, from about 0.2 parts by weight to about 2 parts by weight of carbon black.

The size of the calcium carbonate may be about 30 nm to about 10 탆, and the calcium carbonate may include, but is not limited to, hydrophobic coating on the surface using stearic acid or fatty acid. In one embodiment of the invention, the structural bonding composition may include, but is not limited to, about 2 parts by weight to about 15 parts by weight of calcium carbonate.

The size of the silica may be from about 10 nm to about 50 nm, and may include, but is not limited to, hydrophobicity treated with silane. In one embodiment of the invention, the structural bonding composition may include, but is not limited to, from about 0.5 parts by weight to about 5 parts by weight of silica.

In one embodiment of the present invention, the curing agent may include, but is not limited to, dicyandiamide, acid anhydride, diaminodiphenylmethane (DDM), or diaminophenylsulfone (DDS) .

In one embodiment of the present invention, the curing agent may be, but is not limited to, an epoxy curing agent, including one or more curing agents for crosslinking the epoxy resin.

In one embodiment of the invention, the curing agent may be of the powder type or liquid type having a high viscosity, but may not be limited thereto.

In one embodiment of the present invention, the curing agent may be, but not limited to, dicyandiamide, which is a latent curing agent, to ensure stable storage.

In one embodiment of the present invention, the catalyst may include, but is not limited to, urea-based or imidazole-based compounds.

The catalyst is used to lower the high reaction initiation temperature of the curing agent to optimize the necessary curing conditions. In addition, the catalyst may be used alone as a curing agent as well as a curing agent catalyst, but may not be limited thereto. The catalyst can improve the peel strength, impact strength, heat resistance and the like depending on the structure.

Another aspect of the present invention provides a method for producing a structural adhesive composition, comprising mixing an epoxy resin with a filler and a resin reinforcement, and then adding a curing agent and a catalyst to react to obtain a structural adhesive composition.

In one embodiment of the invention, the epoxy resin may include, but is not limited to, modifying a part of the functional group.

In one embodiment herein, the structural bonding composition comprises from about 60 to about 95 parts by weight of an epoxy resin, from about 2.7 to about 15 parts by weight of a filler, from about 5 to about 10 parts by weight of a curing agent, and from about 0.2 to about 4 parts by weight of a catalyst But the present invention is not limited thereto.

In one embodiment of the invention, it may include, but is not limited to, additional resin reinforcements.

In one embodiment of the present invention, the resin reinforcement may be included in an amount of about 2 to about 20 parts by weight, but may not be limited thereto.

In one embodiment of the invention, the epoxy resin may include but is not limited to those selected from the group consisting of bisphenol A type epoxy resins, polyether modified epoxy resins, and combinations thereof.

In one embodiment herein, the epoxy equivalent (EEW) of the epoxy resin may be from about 100 to about 1000, but is not limited thereto.

In one embodiment of the present invention, the resin reinforcements may include, but are not limited to, those selected from the group consisting of coupling agents, moisture absorbers, dispersants, and combinations thereof.

In one embodiment of the invention, the filler may comprise, but is not limited to, selected from the group consisting of coated carbon black, coated calcium carbonate, silica, and combinations thereof.

In one embodiment of the present invention, the curing agent may include, but is not limited to, dicyandiamide, acid anhydride, diaminodiphenylmethane (DDM), or diaminophenylsulfone (DDS) .

In one embodiment of the present invention, the catalyst may include, but is not limited to, urea-based or imidazole-based compounds.

Another aspect of the present invention provides a structural adhesive comprising the structural adhesive composition according to the above aspect.

The structural adhesive composition of the present application and the method for producing the structural adhesive composition are not described in detail. However, the description of the structural adhesive composition and the method of manufacturing the structural adhesive composition of the present application is based on the structural adhesive The same description can be applied even if the description is omitted.

In one embodiment of the present invention, the structural adhesive may be of the tape type or paste type, but may not be limited thereto.

In one embodiment of the present invention, a laminator & cutter may be used for the structural shaping of the structural adhesive, but the present invention is not limited thereto.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following Examples are given for the purpose of helping understanding of the present invention, but the present invention is not limited to the following Examples.

[ Example ]

< Example  One: Paste type  Preparation of structural adhesive>

55 parts by weight of a bisphenol A type epoxy resin and 23 parts by weight of a polyether-modified epoxy resin were melted in an oven at 130 DEG C for 1 hour, and then the mixture was stirred and mixed at 130 DEG C for 3 hours. Then, 2 parts by weight of carbon black, 7 parts by weight of coated calcium carbonate and 3 parts by weight of fumed silica were added and dispersed at high speed for 2 hours. The temperature of the reactor was lowered to 60 DEG C or less, 7.5 parts by weight of dicyandiamide, and 2 parts by weight of substituted urea 3- (3,4-dichlorophenyl) -1,1-dimethylurea were added and stirred for 1 hour. All of the above processes were conducted in a vacuum state.

< Example  2: Paste type  Preparation of structural adhesive>

50 parts by weight of a bisphenol A type epoxy resin and 20 parts by weight of a polyether-modified epoxy resin were melted in an oven at 130 DEG C for 1 hour and then all of them were measured in a reactor and stirred at 130 DEG C for 3 hours and blended. Then, 2 parts by weight of carbon black, 7 parts by weight of coated calcium carbonate, 3 parts by weight of fumed silica and 9.5 parts by weight of a resin reinforcement were added to the reactor, followed by rapid dispersion for 2 hours. The temperature of the reactor was lowered to 60 占 폚, and 6.5 parts by weight of dicyandiamide and 2 parts by weight of substituted urea 3- (3,4-dichlorophenyl) -1,1-dimethylurea were added and stirred for 1 hour . All of the above processes were conducted in a vacuum state.

< Example  3: Preparation of tape-like structural adhesive>

50 parts by weight of a bisphenol A type epoxy resin and 15 parts by weight of a polyether-modified epoxy resin were melted in an oven at 130 DEG C for 1 hour, and then all of them were measured in a reactor and stirred at 130 DEG C for 3 hours and blended. Then, 2 parts by weight of carbon black, 7 parts by weight of coated calcium carbonate, 3 parts by weight of fumed silica, and 14.5 parts by weight of a resin reinforcement were added and dispersed at high speed for 2 hours to prepare an intermediate. 8.5 parts by weight of dicyandiamide and 1.2 parts by weight of substituted urea 3- (3,4-dichlorophenyl) -1,1-dimethylurea were added to the intermediate prepared above and dispersed for 10 minutes to 15 minutes to prepare a mixture. The mixture was shaped to a bulk state of 3 kg to 5 kg. Cutting & Laminator machine to make a sheet or tape shape with a certain thickness and cut into a tape shape of desired size.

< Example  4: Preparation of tape-like structural adhesive>

60 parts by weight of a bisphenol A type epoxy resin and 10 parts by weight of a polyether-modified epoxy resin were melted in an oven at 130 DEG C for 1 hour, and then all of them were measured in a reactor and stirred at 130 DEG C for 3 hours and blended. Then, 2 parts by weight of carbon black, 7 parts by weight of coated calcium carbonate, 3 parts by weight of fumed silica and 9.5 parts by weight of a resin reinforcement were added to the reactor, and the mixture was rapidly dispersed for 2 hours to prepare an intermediate. To the intermediate thus prepared, 8.5 parts by weight of dicyandiamide and 1.2 parts by weight of substituted urea 3- (3,4-dichlorophenyl) -1,1-dimethylurea were added and dispersed for 10 minutes to 15 minutes to prepare a mixture. The mixture was shaped to a bulk state of 3 kg to 5 kg. Cutting & Laminator machine to make a sheet or tape shape with a certain thickness and cut into a tape shape of desired size.

The compositions of the respective epoxy resins, resin reinforcements, fillers, curing agents and catalysts according to Examples 1 to 4 are shown in Table 1 below.

< Experimental Example  One: Shear strength ( Single lap shear strength ) ( Mpa ) Test>

A steel sheet having a size of 100 mm x 25 mm x 1.6 T was degreased and dried with isopropyl alcohol or toluene, and then the solvent on the surface was removed with a clean cloth. The adhesive prepared in the above example was applied to one side of a cold-rolled steel sheet (CR) and a galvanized steel sheet (GA) and bonded at an overlap of 12.5 mm. The sample was fixed with a joint clip (compressive force of about 0.3 kg), cured at 180 ° C for 20 minutes, and then allowed to stand at 22 ° C and a relative humidity of 65% for 1 hour. The shear strength test specimens were subjected to a tensile load in a 180 ° direction at a tensile rate of 5 mm / min in a universal material tester (SHIMADZU, AG-X plus). The shear strength was determined from the load-displacement curves of the automatic recording apparatus attached to the universal material testing machine, and the average value of the trials was described.

< Experimental Example  2: T- Peel strength (T- peel strength ) (N / 25 mm ) Test>

The steel sheet having a size of 150 mm x 300 mm x 0.8 T was degreased with isopropyl alcohol or toluene and dried, and then the solvent on the surface was removed with a clean cloth. The adhesive prepared in the above example was applied to one side of a cold-rolled steel sheet (CR) and a galvannealed steel sheet (GA) steel sheet in an amount of 25 mm x 220 mm, and then the other steel sheet was bonded. The joint was clamped with a clip (compressive force of about 0.3 kg), cured at 180 ° C for 20 minutes, and then allowed to stand at 22 ° C and a relative humidity of 65% for 1 hour. The T-peel strength test piece was subjected to a tensile load in a 180 ° direction at a tensile speed of 50 mm / min in a universal material testing machine (SHIMADZU, AG-X plus). The T-peel strength (N / 25 mm) is the average value of the 50 mm length after the first maximal value from the load-displacement curve of the automatic recorder attached to the tensile tester, .

The results according to Experimental Examples 1 and 2 are shown in Tables 2 and 3 below.

The tensile strength and the peel strength of the adhesive obtained in this example showed an improvement of 50% or more as compared with the conventional adhesive. In particular, as shown in Table 2, it was found that the peel strength of the present example exhibited a high strength of about 350 N / 25 mm.

It will be understood by those of ordinary skill in the art that the foregoing description of the embodiments is for illustrative purposes and that those skilled in the art can easily modify the invention without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be interpreted as being included in the scope of the present invention .

Claims (16)

An epoxy resin, a filler, a curing agent, and a catalyst.
The method according to claim 1,
Wherein the structural adhesive composition comprises 60 to 95 parts by weight of an epoxy resin, 2.7 to 15 parts by weight of a filler, 5 to 10 parts by weight of a curing agent, and 0.2 to 4 parts by weight of a catalyst.
The method according to claim 1,
And further comprising a resin reinforcement.
The method of claim 3,
Wherein the resin reinforcement is contained in an amount of 2 to 20 parts by weight.
The method according to claim 1,
Wherein the epoxy resin comprises a resin selected from the group consisting of a bisphenol A type epoxy resin, a polyether-modified epoxy resin, and combinations thereof.
The method according to claim 1,
Wherein the epoxy equivalent (EEW) of the epoxy resin is 100 to 1,000.
The method according to claim 1,
Wherein the resin reinforcement comprises a material selected from the group consisting of a coupling agent, a moisture absorbent, a dispersant, and combinations thereof.
The method according to claim 1,
Wherein the filler comprises a material selected from the group consisting of coated carbon black, coated calcium carbonate, silica, and combinations thereof.
The method according to claim 1,
Wherein the curing agent comprises dicyandiamide, acid anhydride, diaminodiphenylmethane (DDM), or diaminophenylsulfone (DDS).
The method according to claim 1,
Wherein the catalyst comprises a urea-based or imidazole-based compound.
Mixing an epoxy resin with a filler and a resin reinforcement, adding a curing agent and a catalyst, and reacting to obtain a structural adhesive composition
&Lt; / RTI &gt;
12. The method of claim 11,
Wherein the epoxy resin comprises modifying a part of the functional group.
12. The method of claim 11,
Wherein the curing agent comprises dicyandiamide, acid anhydride, diaminodiphenylmethane (DDM), or diaminophenylsulfone (DDS).
12. The method of claim 11,
Wherein the catalyst comprises a urea-based or imidazole-based compound.
A structural adhesive comprising the structural adhesive composition according to any one of claims 1 to 10.
16. The method of claim 15,
Wherein the structural adhesive is a tape-like or paste-type structural adhesive.