KR101013601B1 - Epoxy adhesive composition for membrane structure of ????? type - Google Patents

Abstract

The present invention relates to an epoxy adhesive composition for a Mark III type membrane structure, which is a type of membrane structure of a liquefied natural gas carrier, comprising a bisphenol A type epoxy resin and a carboxyl-terminated butadiene-acrylonitrile copolymer (CTBN) modified epoxy resin. A subject comprising an epoxy resin, a urethane-modified epoxy resin, fillers and additives; And a curing agent containing a polyamide resin, an amine-terminated reactive liquid rubber, and a non-reactive organic diluent. Epoxy adhesive of the present invention having the above composition is used for the bonding of the hull material coated with plywood (insulation panel) and primer used in liquefied natural gas carriers, this invention is required as an adhesive for membrane structure of Mark III type It has excellent mechanical properties such as tensile strength, shear strength, and compressive strength at room temperature and low temperature, and has a low coefficient of linear expansion, thereby maintaining adhesive strength even at low temperatures.

Adhesive, Epoxy, Polyamide, Adhesive Strength, Bonding Workability

Description

Epoxy adhesive composition for membrane structure of マ リ} Ⅲ type

The present invention relates to an epoxy adhesive composition for a membrane structure of Mark III type. Specifically, in order to form a cargo hold structure (gas storage tank) in a liquefied natural gas carrier, high adhesion of a heat insulating material composed of a hull of a carrier and plywood and polyurethane foam The present invention relates to an epoxy adhesive composition capable of maintaining high adhesive strength even in a low temperature region (-25 ° C. or less) due to the use characteristics of the cargo hold structure.

In general, liquefied natural gas carriers are liquefied liquefied natural gas at -163 ℃ and transported from gas producing country to consuming country. It has special cargo hold structure to prevent the leakage of gas, and its shape is divided into two types. . The first is divided into Mohs type, which is a rounded circular structure, and the second is liquefied natural gas carrier of membrane structure. It is detailed. However, the membrane structure is divided into two types, MARK III and NO96 type. In LNG carriers, the cargo hold, which is responsible for the storage of liquefied gases, consists of various materials, and the types of adhesives applied are classified according to their characteristics and uses. Therefore, the adhesive used for the LNG carrier should have the function of bonding the hull and the multi-layered insulation panel and the function of dispersing the weight applied to the structure.

In general, an adhesive using a polyamide resin or an amine-based curing agent as the main component has an advantage of excellent adhesive strength in a cured state, but has a disadvantage in that brittleness and peeling strength are very weak due to its low flexibility. . Therefore, there is a problem in that the adhesion state is significantly weakened when the impact is applied or the rapid temperature change is repeated between the bonded materials over time.

In particular, the epoxy resin adhesive at room temperature is excellent in adhesive strength, but at low temperatures, the adhesive strength is significantly reduced, and the environment of using the epoxy resin adhesive composition of the present invention is used in ships storing and transporting liquefied petroleum gas. And the adhesive strength in the low temperature region (-25 ° C.) is an important item. Accordingly, there is a demand for the development of a product having excellent adhesion strength in the low temperature range of room temperature and -25 ° C and low expansion and contraction according to the temperature.

In order to solve the shortcomings of the epoxy adhesive, a modified or modified epoxy resin is used to impart elasticity to the epoxy resin. That is, CTBN-modified epoxy resin or urethane-modified epoxy resin, which is modified by reacting NBR (nitrile butadiene rubber) with epoxy resin and carboxyl-terminated butadiene acrylonitrile copolymer (CTBN) under catalyst, is used. will be.

The present invention is to maintain the adhesive strength of the epoxy adhesive in the room temperature and low temperature region, to implement a linear expansion coefficient of 60 × 10 ^-5 mm / mm ℃ or less to minimize the deformation of the adhesive according to the temperature change, The purpose is to solve the problem of flowing down during the application of the epoxy adhesive due to poor workability.

The present invention for solving the above problems is the Mark III-type membrane structure epoxy adhesive composition comprising a main agent and a curing agent (A) epoxy resin containing a bisphenol A-type epoxy resin and CTBN (carboxyl-terminated acrylonitrile copolymer) modified epoxy resin, A subject matter containing (B) a urethane-modified epoxy resin, (C) filler, and (D) additive; And a curing agent containing (E) a polyamide resin, (F) amine-terminated reactive liquid rubber, (G) non-reactive organic diluent, (H) filler, and (I) additive. do.

The present invention not only has excellent physical properties such as shear strength, tensile strength, and compressive strength at room temperature and low temperature, but also has a low coefficient of linear expansion, so that deformation of the adhesive due to temperature change can be minimized. The workability that does not flow down when the adhesive is applied is good.

The present invention will be described in detail below.

The present invention relates to an epoxy adhesive composition for Mark III type membrane structure, comprising: (A) an epoxy resin containing a bisphenol A epoxy resin and a carboxyl-terminated acrylonitrile copolymer (CTBN) modified epoxy resin, (B) a urethane modified epoxy resin (C ) A filler, and a subject containing (D) an additive; And a curing agent containing (E) a polyamide resin, (F) amine-terminated reactive liquid rubber, (G) non-reactive organic diluent, (H) filler, and (I) additive. do.

When the present invention is divided into the subject and the curing agent, the (A) epoxy resin, which is one of the subject compositions, simultaneously contains bisphenol A type epoxy resin and CTBN (carboxyl-terminated acrylonitrile copolymer) modified epoxy resin. In case of using epoxy resin alone, it has the disadvantage of being hard and brittle in the hardened state, so in order to compensate for this brittleness (fragile property), the product name CTBN1300 * 31, CTNB1300 * of Novean There is a technical feature in using a CTBN modified epoxy resin modified by synthesizing an epoxy resin and a discontinued or two or more selected from 18, CTBN1300 * 8, and CTBN1300 * 13 with a bisphenol A epoxy resin.

In addition, the CTBN modified epoxy resin was introduced to provide flexibility to the epoxy adhesive, to improve the brittleness of the epoxy resin, and to maintain the adhesive strength at low temperature, and to change the physical properties according to the type of CTBN to undergo the modification reaction with the epoxy resin. Synthesis method is a reaction of CTBN and epoxy resin with an average epoxy equivalent of 180 to 250 g / eq until the acid value reaches 0.1 when catalyzed by triphenyl phosphine and the reaction temperature is 85 to 95 ℃. Can be obtained. CTBN used in the preparation of the CTBN modified epoxy resin may have an average molecular weight of 3,000 to 5,000 g / mol, more preferably 3,000 to 3,800 g / mol, and a glass transition temperature of -38 to -66 ° C. For example, Novean's Hyper CTBN 1300 * 31, Hyper CTBN 1300 * 13, Hyper CTBN 1300 *, Hyper CTBN 1300 * 18, etc. may be used alone or in combination.

The CTBN modified epoxy resin prepared by the method described above may use an average epoxy equivalent of 300 ~ 500 g / eq, more preferably 350 ~ 400 g / eq.

The urethane-modified epoxy resin (B), which is one of the main components, serves to complement the room temperature and low temperature flexibility of the adhesive to lower the elastic modulus and improve the elongation. The urethane-modified epoxy resin is a modified part of the epoxy resin with a urethane prepolymer, the urethane-modified epoxy resin is epoxy equivalent range of 200 ~ 400 g / eq, more preferably 250 ~ 350 g / eq can be used. The urethane-modified epoxy resin may specifically include UME315, UME330, UME305, and Hypox UA10, manufactured by Kukdo Chemical.

The filler (C) may be used commonly used in the art, and is not particularly limited, but may be used in combination or in combination of one or more selected from calcium carbonate, bentonite, fume silica, wollastonite, silica, kaolin and mica. More preferably, one or two selected from calcium carbonate and fume silica may be used in consideration of thixotropy and workability.

Finally, the additive (D), which is a component of the subject matter, may be one commonly used in the art, and one or two or more kinds selected from a flow inhibitor, a viscosity modifier, an antifoaming agent, and a dispersant may be used.

Next, the hardening | curing agent which is a component of the epoxy adhesive of this invention is demonstrated in detail.

The polyamide resin (E), which is one of the hardener components, may use a conventional polyamide resin used in the art, and preferably may have an amine number of 200 to 350 mg KOH / g. Currently commercially available polyamide resins include LA1030, LA0240, LA6022, and LAD713 from Hexion Corp., and single or two or more selected from these may be used in the present invention.

The (F) amine-terminated reactive liquid rubber as a hardener component gives the toughness and flexibility of the epoxy adhesive according to the present invention, thereby improving adhesion and improving elongation and elastic modulus of tensile strength, which are mechanical properties at low temperatures. The amine-terminated reactive liquid rubber is one or more selected from the group consisting of amine-terminated butadiene acrylonitrile rubber, Novean's Hyper21 ATBN, Hyper16 ATBN, Hyper35 ATBN, and Hyper42 ATBN. Liquid rubber can be mixed and used. The amine-terminated reactive liquid rubber can be used an amine equivalent 400 ~ 1,300 g / eq, more preferably 700 ~ 1,000 g / eq, can be used a glass transition temperature of -35 ~ -65 ℃ .

The (G) non-reactive organic diluent, which is one of the curing agent components, serves to provide the effect of improving workability by imparting the flexibility or viscosity of the epoxy adhesive according to the present invention, which is used in the art. Ordinarily used in the can be used, not particularly limited, benzyl alcohol, diisonyl phthalate and dioctyl phthalate selected from the group consisting of two or more may be used.

The (H) filler, which is another one of the curing agent components, may be one that is commonly used in the art, and is not particularly limited, but one or two or more selected from calcium carbonate, bentonite, fume silica, wollastonite, silica and mica These may be used in combination, more preferably single or two selected from calcium carbonate and fume silica may be used.

Finally, the additive (I) in the curing agent component may be selected from the group consisting of single or two or more curing accelerators selected from fatty acid polyamines, aromatic amines and aliphatic amines; Flow inhibitors; Viscosity modifiers; Antifoams and dispersants; Single or two or more types selected from among these may be used, and those commonly used in the art may be used.

Hereinafter, the Mark III type membrane adhesive epoxy adhesive composition of the present invention will be described in detail with the composition ratio of the composition materials.

The epoxy adhesive composition of the present invention is based on 100 parts by weight of (A) epoxy resin containing bisphenol A epoxy resin and CTBN (carboxyl-terminated butadiene-acrylonitrile copolymer) modified epoxy resin, (B) urethane modified epoxy resin 15-30 Weight parts (C) 100 to 200 parts by weight of filler and (D) 5 to 15 parts by weight of additives; And (E) 10 to 30 parts by weight of (F) amine-terminated reactive liquid rubber, (G) 15 to 30 parts by weight of non-reactive organic diluent, (H) 100 to 200 parts by weight of polyamide resin. And a curing agent containing 10 to 20 parts by weight of the additive by weight and (I) the additive.

And the epoxy adhesive composition of this invention is characterized by using the said main body and the said hardening | curing agent by mixing in 1 weight: 0.7-0.9 weight ratio.

The (A) epoxy resin is a mixture of bisphenol A-type epoxy resin and carboxyl-terminated acrylonitrile copolymer (CTBN) modified epoxy resin, more specifically, 60 to 80% by weight bisphenol A epoxy resin and 20 to 40 CTBN modified epoxy resin It is characterized by containing a weight%. Here, when the CTBN modified epoxy resin is less than 20% by weight, the adhesive strength at room temperature is high, but the adhesive strength in the low temperature region (-25 ° C. or less) is greatly reduced, and the elongation at the low temperature region is not satisfied. When the CTBN modified epoxy resin is more than 40% by weight, the elongation of the tensile strength may be improved, but the compressive strength may be reduced. Therefore, the CTBN modified epoxy resin may be used within the above range. In addition, the amount of the bisphenol A epoxy resin is relatively determined according to the amount of CTBN-modified epoxy resin. The urethane-modified epoxy resin (B) may be used 15 to 30 parts by weight based on 100 parts by weight of the epoxy resin (A), if the urethane-modified epoxy resin is less than 15 parts by weight, the effect of improving the modulus and elongation at low temperature If it is not more than 30 parts by weight, the elastic modulus at room temperature may be lowered, so it is preferable to use within the above range.

 The filler (C) may be used 100 to 200 parts by weight based on 100 parts by weight of the epoxy resin (A), if the filler is less than 100 parts by weight may cause a problem of poor workability due to low viscosity, when exceeding 200 parts by weight Since a phenomenon in which viscosity and specific gravity are increased and workability may be deteriorated may occur, it is preferable to use within the above range.

The additive (D) may be used 5 to 15 parts by weight based on 100 parts by weight of the epoxy resin (A), if the additive is less than 5 parts by weight may cause a problem that can not see the effect enhancement by the additive, 15 weight Since excessive problems may result in poor adhesion and workability, it is preferable to use within the above range.

The (E) amine-terminated reactive liquid rubber as a hardener component may be used in an amount of 10 to 30 parts by weight based on 100 parts by weight of the polyamide resin. A problem may occur, and when the amount exceeds 30 parts by weight, flexibility at room temperature may be increased, thereby lowering the adhesive strength and the compressive strength.

And the (F) non-reactive organic diluent may be used 15 to 45 parts by weight based on 100 parts by weight of the polyamide resin, when the amount is less than 15 parts by weight may cause a problem of high viscosity and low plasticity, 45 When exceeding the weight part, the problem of low adhesive strength and viscosity and poor workability may occur. Therefore, it is preferable to use within the above range.

The filler (G), which is one of the curing agent components, may be used in an amount of 100 to 200 parts by weight based on 100 parts by weight of the polyamide resin, but when the filler is less than 100 parts by weight, a problem may occur in which the viscosity is lowered. Since the viscosity may increase, the fluidity may be worsened, and the specific gravity may be increased. Therefore, the viscosity may be used within the above range.

Lastly, the (H) additive, which is one of the curing agent components, may be one that is commonly used in the art, and one or two or more selected from flow inhibitors, viscosity regulators, antifoaming agents and dispersants, accelerators, and the like may be used. The accelerator may be used by mixing one or two or more selected from fatty acid polyamines, aromatic amines and cycloaliphatic amines, and the accelerator may be used in an amount of 5 to 15 parts by weight based on 100 parts by weight of the (E) polyamide resin. In this case, when the amount of the accelerator is less than 5 parts by weight, there may be a problem in that the pot life is increased to increase the curing time, and when the amount is greater than 15 parts by weight, the pot life may be too fast, resulting in poor workability. It is good to use within the said range.

Epoxy adhesive composition of the present invention is characterized in that the mixing of the main material and the curing agent having the above composition in a weight ratio of 1: 0.7 to 0.9, wherein the mixing ratio of the main material and the curing agent is less than 1: 0.7 by weight The problem may occur that the speed is lowered and the adhesive strength is lowered, and when the mixing ratio of the main material and the curing agent is greater than 1: 0.9 weight ratio based on the weight ratio, the curing speed may be increased. It is preferable.

The subject having the composition and composition ratio as described above has a specific gravity of 1.50 to 1.60 and a viscosity of 8,000 to 10,000 Ps (20 ° C.), and the curing agent has a specific gravity of 1.30 to 1.40 and a viscosity of 5,000 to 6,500 Ps (20 ° C.). Has In addition, the epoxy adhesive prepared from the Mark III type membrane adhesive epoxy adhesive composition of the present invention including the main agent and the curing agent has an initial mixing viscosity of 6,000 to 10,000 Ps (20 ° C.) at the time of mixing the main agent and the curing agent. The epoxy adhesive composition of the present invention can be used as an adhesive between discontinuous or two or more materials selected from common steel sheet, plywood and primer coated metals.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the scope of the present invention is not limited by the embodiment.

Production Example

Preparation of CTBN Modified Epoxy Resin

67 wt% bisphenol A epoxy resin with an average equivalent weight of 180 to 190 g / eq and CTBN (carboxyl-terminated butadiene acrylonitrile copolymer, trade name Hypro CTBN 1300 * 31, average molecular weight 3,800 g / mol, glass transition temperature -66 ℃) 33 The wt% mixture was reacted with a triphenyl phosphine catalyst and a reaction temperature of 93 to 95 ° C. until an acid value of 0.1 was obtained to prepare a CTBN modified epoxy resin having an average equivalent weight of 350 to 370 g / eq. Example epoxy adhesives were used.

Examples 1-9 and 1-4 in comparison

Preparation of Mark III Type Membrane Structure Epoxy Adhesive

The epoxy adhesive composition of the present invention including the main ingredient and the curing agent having the compositional components and the composition ratios shown in Table 1 was mixed and stirred at a weight ratio of 1: 0.8 at a temperature of about 25 ° C. to prepare an epoxy adhesive for Mark III type membrane structures. In Table 1 below, the additive includes a flow inhibitor, a viscosity modifier, an antifoaming agent, and a dispersant, and the amount of the additive was used in an equal ratio with respect to the total weight of the additive.

Experimental Example

Physical property test

The physical properties of the epoxy adhesives prepared in Examples 1 to 9 and Comparative Examples 1 to 4 were measured using the test methods described in Table 2 below. The results are shown in Table 3 below. When the physical property range of Table 2 is satisfied, it has excellent physical properties for use as Mark III type membrane structural epoxy adhesive of liquefied natural gas carriers.

Looking at the experimental results of Table 3, it can be seen that the physical properties of the epoxy adhesive composition of the present invention more excellent than the comparative example, in particular it can be confirmed that the tensile strength is very excellent. As such, the epoxy adhesive composition of the present invention is bonded by mixing an epoxy resin-based main body comprising a glycidyl ether-based reactive diluent with a polyamide-based curing agent comprising an amine-terminated reactive liquid rubber and a non-reactive organic diluent. It is excellent in workability and has high adhesive strength even in a low temperature range.

Claims (6)

In the epoxy adhesive composition comprising a main material and a curing agent, A subject containing (A) an epoxy resin, (B) a urethane-modified epoxy resin (C) filler, and (D) additives containing a bisphenol A epoxy resin and a carboxyl-terminated acrylonitrile copolymer (CTBN) modified epoxy resin; And Curing agent containing (E) polyamide resin, (F) amine-terminated reactive liquid rubber, (G) non-reactive organic diluent, (H) filler, and (I) additive; Epoxy adhesive composition for Mark III type membrane structure, characterized in that it comprises a. The method of claim 1, The main subject is 15 to 30 parts by weight of (B) urethane-modified epoxy resin, (C) 100 to 200 parts by weight of (B) urethane-modified epoxy resin, based on 100 parts by weight of (A) epoxy resin containing bisphenol A type epoxy resin and CTBN modified epoxy resin, And (D) 5 to 15 parts by weight of an additive, The curing agent (E) 5 to 20 parts by weight of the (F) amine-terminated reactive liquid rubber, (G) 15 to 45 parts by weight of the non-reactive organic diluent, (H) filler 100 to 100 parts by weight of the polyamide resin Epoxy adhesive composition for Mark III type membrane structure, characterized in that it contains ~ 200 parts by weight, and (I) 5 ~ 15 parts by weight of the additive. The method according to claim 1 or 2, Epoxy adhesive composition for Mark III type membrane structure, characterized in that the main material and the curing agent are mixed in a weight ratio of 1: 0.7 to 0.9. The method according to claim 1 or 2, Epoxy adhesive composition for Mark III type membrane structure, characterized in that the CTBN modified epoxy resin has an average epoxy equivalent weight of 350 ~ 400 g / eq. The method according to claim 1 or 2, The polyamide resin has an amine number of 200 ~ 350 mg KOH / g Mark III type membrane structure epoxy adhesive composition. The method according to claim 1 or 2, The amine-terminated reactive liquid rubber is an epoxy adhesive composition for Mark III type membrane structure, characterized in that the amine equivalent 700 ~ 1,000 g / eq and the glass transition temperature -38 ~ -65 ℃.