Polyol premix composition for glass fiber composite insulation material for liquefied gas storage tanks

Abstract

The present invention aims to provide a polyol premix composition for forming glass fiber reinforced polyurethane foam for liquefied gas storage tanks. [Solution] The present invention relates to a polyol premix composition for forming glass fiber reinforced polyurethane foam, comprising a polyol including a polyether polyol, a polyester polyol, and an isosorbide-containing polyol, and glass fibers, wherein the isosorbide-containing polyol is present in an amount of 10 to 60% by weight of the total weight of the polyol; a glass fiber reinforced polyurethane foam prepared using the same; a glass fiber composite insulation material containing the glass fiber reinforced polyurethane foam; and a liquefied gas storage tank containing the glass fiber composite insulation material.

Description

Technical Field

[0001] The present invention relates to a polyol premix composition for a glass fiber composite thermal insulation material for a liquefied gas storage tank, and more specifically, to a polyol premix composition for forming a glass fiber reinforced polyurethane foam, a glass fiber reinforced polyurethane foam prepared using the same, a glass fiber composite thermal insulation material including the glass fiber reinforced polyurethane foam, and a liquefied gas storage tank including the glass fiber composite thermal insulation material.

Background Art

[0002] A liquefied gas carrier is a ship that transports liquefied gas such as liquefied natural gas (LNG) in a cryogenic state of about -165°C or lower, and is equipped with facilities for storing and preserving liquefied gas. It is important to design a cargo storage system (CCG), that is, a liquefied gas storage tank, so that the liquefied gas carrier can transport the liquefied gas to the destination while maintaining it at an extremely low temperature.

[0003] In a liquefied gas storage tank, there is a possibility that boil-off gas (BOG) may be generated due to heat intrusion into the liquefied gas storage tank. Therefore, it is preferable to reduce the natural vaporization rate (BOR), which is the vaporization ratio of the boil-off gas, through the thermal insulation design of the liquefied gas storage tank. In addition, since the liquefied gas storage tank is exposed to various loads such as sloshing of the liquefied gas, it is also essential to ensure mechanical strength in the part that receives the load from the liquefied gas.

[0004] For such purposes, the liquefied gas storage tank may include a first barrier with which the liquefied gas directly contacts to maintain an extremely low temperature, a first thermal insulation member provided outside the first barrier, a second barrier provided outside the first thermal insulation member, and a second thermal insulation member provided outside the second barrier.

[0005] The insulation components consist of insulating materials and insulating panels, which block heat exchange between the liquefied gas storage tank and the outside, keeping the inside of the liquefied gas storage tank at an extremely low temperature. This prevents the evaporation of the liquefied gas inside the storage tank while also preventing damage to the ship's hull from the extremely low temperature of the liquefied gas.

[0006] The thermal insulation component must be made of a material with excellent thermal insulation performance and mechanical strength so that it can withstand external impacts or internal impacts caused by liquefied gas sloshing while blocking heat intrusion from outside the liquefied gas storage tank. The thermal insulation component may consist solely of thermal insulation material, or it may be in the form of a laminate of thermal insulation panels and thermal insulation material.

[0007] The insulation material may include glass fiber composite insulation, which has excellent thermal insulation performance and mechanical strength. Glass fiber composite insulation is made by adding polymer materials such as polyether, polyester, and isocyanate, along with reinforcing materials such as glass fibers, to polyurethane foam to enhance its mechanical strength.

[0008] While glass fibers possess excellent mechanical strength, their high thermal conductivity means that while the mechanical strength of an insulating material can be increased, its thermal insulation performance may decrease. Therefore, increasing the mechanical strength of polyurethane foam using reinforcing materials such as glass fibers can lead to a decrease in thermal insulation performance. This problem of reduced thermal insulation performance is a technical obstacle when using conventional glass fiber composite insulation materials as insulation for liquefied gas storage tanks. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Korean Patent Publication No. 10-2006-0096378 [Patent Document 2] Korean Patent Publication No. 10-2020-0036458 [Patent Document 3] Korean Patent Publication No. 10-2011-0003703 [Patent Document 4] Korean Patent Publication No. 10-2012-0077215 [Overview of the project] [Problems that the invention aims to solve]

[0010] The present invention aims to provide a polyol premix composition for forming glass fiber reinforced polyurethane foam for liquefied gas storage tanks.

[0011] Furthermore, the present invention aims to provide a glass fiber composite insulation material for liquefied gas storage tanks that has improved thermal insulation properties and mechanical properties in cryogenic environments when using the above composition.

[0012] The above and other objectives and advantages of the present invention will become apparent from the following description illustrating preferred embodiments. [Means for solving the problem]

[0013] The present invention provides a polyol premix composition for forming glass fiber-reinforced polyurethane foam, comprising polyols including polyether polyols, polyester polyols, and isosorbide-containing polyols, and glass fibers, wherein the isosorbide-containing polyol is present in an amount of 10 to 60% by weight of the total weight of the polyols.

[0014] Furthermore, the present invention provides a glass fiber reinforced polyurethane foam prepared by reacting an isocyanate with the above-mentioned polyol premix composition for forming glass fiber reinforced polyurethane foam.

[0015] Furthermore, the present invention provides a glass fiber composite insulation material containing the above-mentioned glass fiber reinforced polyurethane foam.

[0016] Furthermore, the present invention provides a liquefied gas storage tank containing the above-mentioned glass fiber composite insulation material. [Effects of the Invention]

[0017] The polyol premix composition for forming glass fiber reinforced polyurethane foam according to an embodiment of the present invention can provide a glass fiber reinforced polyurethane foam and a glass fiber composite heat insulating material with improved thermal conductivity, tensile strength, and shear strength in an extremely low temperature environment as compared with a pure glass fiber composite heat insulating material.

[0018] The glass fiber composite heat insulating material according to an embodiment of the present invention can have excellent heat insulating properties and mechanical physical properties, particularly in an extremely low temperature environment, as compared with a conventional glass fiber composite heat insulating material. A liquefied gas storage tank containing such a heat insulating material can reduce the preparation cost and installation cost by thinning the thickness of the heat insulating material due to the improvement of its physical performance.

[0019] The liquefied gas storage tank containing the glass fiber composite heat insulating material according to an embodiment of the present invention can improve the heat insulating performance by using a foaming composition containing isosorbide single molecules, minimize the loss amount associated with the natural vaporization of the liquefied gas, and reduce the preparation and installation costs by reducing the thickness of the heat insulating material.

[0020] However, the effects of the present invention are not limited to the above effects, and other effects not described will be clearly understood by those skilled in the art from the following description.

Mode for Carrying Out the Invention

[0021] Hereinafter, the present invention will be described in detail.

[0022] <Polyol Premix Composition for Forming Glass Fiber Reinforced Polyurethane Foam> The polyol premix composition for forming glass fiber reinforced polyurethane foam according to an embodiment of the present invention contains a polyol including a polyether polyol, a polyester polyol, and an isosorbide-containing polyol, and glass fibers, and the isosorbide-containing polyol is 10 to 60% by weight of the total weight of the polyol.

[0023] As described above, although glass fibers have excellent mechanical strength, their high thermal conductivity may cause the mechanical strength of the heat insulation member to increase but the heat insulation performance to decrease when glass fibers are included in the heat insulation material.

[0024] The polyol premix composition for forming glass fiber reinforced polyurethane foam of the present invention contains a polyether polyol, a polyester polyol, a polyol containing isosorbide, and glass fibers.

[0025] The polyol premix composition for forming glass fiber reinforced polyurethane foam of the present invention contains a polyol containing isosorbide in order to improve the heat insulation characteristics and mechanical physical properties of the glass fiber reinforced polyurethane foam in an extremely low temperature environment. Isosorbide is a bicyclic compound of a diol containing two fused furan rings and a heterocyclic compound containing oxygen. The above polyol containing isosorbide can be prepared by subjecting isosorbide to a condensation reaction with an ester polyol via an esterification reaction.

[0026] Preferably, the polyol containing isosorbide has an acid value of 0.5 to 2.5 mgKOH / g, an average hydroxyl value of 250 mgKOH / g to 400 mgKOH / g, and an isosorbide content of 5 to 20% by weight of the ester polyol.

[0027] The content of the polyol containing isosorbide contained in the polyol premix composition for forming glass fiber reinforced polyurethane foam of the present invention is preferably 10 to 60% by weight of the total weight of the polyol. More preferably, it is 30 to 60% by weight. Although the heat insulation characteristics and mechanical physical properties in an extremely low temperature environment increase as the addition amount of isosorbide increases, when isosorbide above a certain level is added, the effect of improving the heat insulation characteristics and mechanical physical properties in an extremely low temperature environment decreases.

[0028] The inventors have confirmed that when the isosorbide-containing polyol content in polyurethane foam exceeds 60% by weight, the viscosity of the polyol composition increases, leading to problems with moldability (impregnation of raw material and CFM distribution) during the preparation of glass fiber composite insulation material, and ultimately resulting in a decrease in the mechanical properties of the glass fiber composite insulation material.

[0029] The above polyether polyols can be polymerized by adding propylene oxide (PO) or ethylene oxide (EO) to an initiator containing a compound with 2 to 8 hydroxyl groups per molecule. The initiator may include any one or more selected from the group consisting of sorbitol, sucrose, glycerine, pentaerythritol, trimethylol, ethylene glycol, and propylene glycol. One or more initiators may be used in combination; for example, two or more initiators may be used in combination.

[0030] In one embodiment of the present invention, the polyether polyol may be a polyether polyol having an average hydroxyl value of 100 mg KOH / g to 500 mg KOH / g.

[0031] For example, the above polyether polyol may be obtained by addition polymerization using sorbitol, sucrose, or glycerin as an initiator.

[0032] The above-mentioned polyester polyol may have an acid value of 0.5 to 2.5 mg KOH / g and an average hydroxyl value of 250 mg KOH / g to 400 mg KOH / g.

[0033] For example, the above polyester polyol may include compounds polymerized using one or more selected from the group consisting of phthalic anhydride, terephthalic acid, adipic acid, ethylene glycol, and diethylene glycol as raw materials.

[0034] Specifically, the above-mentioned polyester polyol may be one polyol or a mixture of two polyols obtained by reacting with phthalic anhydride, terephthalic acid, isophthalic acid, benzoic acid and / or adipic acid and / or ethylene glycol.

[0035] The polyol premix composition of the present invention further contains glass fibers to ensure the mechanical strength of the polyurethane foam. The glass fibers are preferably in the form of a glass fiber mat laminate.

[0036] The fiber reinforcement material may be one or more selected from synthetic fibers such as glass fibers, polyamides, and polyesters, or inorganic fibers such as carbon fibers and ceramic fibers, but a glass fiber mat laminate is more preferred.

[0037] Glass fibers may be included in the composition in an amount of 7 to 25 parts by weight per 100 parts by weight of polyol. To ensure low-temperature shrinkage stability of polyurethane foam and prevent crack formation, glass fibers may be included in the composition in an amount of 7 parts by weight or more per 100 parts by weight of polyol. To prevent abnormal foaming during polyurethane foam formation and cracking of polyurethane foam, glass fibers may be included in the composition in an amount of 25 parts by weight or less per 100 parts by weight of polyol.

[0038] The above composition may further contain a foaming agent.

[0039] The blowing agent mentioned above may be one or more selected from either a physical blowing agent or a chemical blowing agent (CO2) using water.

[0040] Specifically, the blowing agent may be one or more selected from the physical blowing agents HFC-245fa, HCFO-1233zd, HFO-1336mzz, cyclopentane, and CO2 produced from a chemical blowing agent using water. The blowing agent may be included in the composition in an amount of 0.5 to 30 parts by weight per 100 parts by weight of polyol. Furthermore, the blowing agent of the present invention does not necessarily contain water as an auxiliary blowing agent.

[0041] The above composition may further contain a reaction catalyst.

[0042] The above reaction catalyst can accelerate or delay the reaction rate between the polyol and polymethylenediphenyl diisocyanate without directly participating in the polymerization reaction.

[0043] The above reaction catalyst may be an amine-based catalyst commonly used in the preparation of polyurethane foam, and may be included in a composition in an amount of 0.05 to 0.5 parts by weight per 100 parts by weight of polyol. Specifically, the reaction catalyst of the present invention may be triethylamine, tripropylamine, triisopropanolamine, tributylamine, trioctylamine, hexadecyldimethylamine, N-methylmorpholine, N-ethylmorpholine, N-octadecylmorpholine, monoethanolamine, diethanolamine, dimethylethanolamine, triethanolamine, N-methyldiethanolamine, N,N-dimethylethanolamine, diethylenetriamine, N,N,N',N'-tetramethylbutanediamine, N,N,N',N'-tetramethyl-13-butanediamine, N,N,N',N'-tetraethyl Examples of amine catalysts include xamethylenediamine, bis[2-(N,N-dimethylamino)ethyl] ether, N,N-dimethylbenzylamine, N,N-dimethylcyclohexylamine, N,N,N',N',n-pentamethyldiethylenetriamine, triethylenediamine, formic acid of triethylenediamine, aminooxyalkylene adducts of primary and secondary amines, Azagoli compounds such as N,N-dialkylpiperazines, and β-aminocarbonyl catalysts of various N,N',N''-trialkylaminoalkylhexahydrotriazines. These catalysts may be included in the composition individually or in combination. However, this is merely an illustrative description of reaction catalysts used in the preparation of polyurethane foam, and the reaction catalysts of the present invention are not necessarily limited thereto.

[0044] The above composition may further contain other additives.

[0045] Other additives may be, but are not limited to, one or more of the following: chain extenders, surfactants, emulsifiers, foam stabilizers, flame retardants, and dyes.

[0046] As an example, a polyol premix composition for forming glass fiber-reinforced polyurethane foam may include polyols containing polyether polyols, polyester polyols, and isosorbide-containing polyols, glass fibers, a blowing agent, a reaction catalyst, a chain extender, and a surfactant.

[0047] <Glass fiber reinforced polyurethane foam> Furthermore, a glass fiber reinforced polyurethane foam according to one embodiment of the present invention is prepared by reacting the above-mentioned glass fiber reinforced polyurethane foam forming composition with an isocyanate.

[0048] A glass fiber reinforced polyurethane foam according to one embodiment of the present invention can be prepared by reacting a polyol containing isosorbide with an isocyanate in the presence of a blowing agent, a reaction catalyst, and other additives.

[0049] In other words, a glass fiber reinforced polyurethane foam according to one embodiment of the present invention can be prepared using a composition comprising a polyol containing isosorbide, an isocyanate, a reaction catalyst, a blowing agent, water, and other additives.

[0050] The above-mentioned isocyanate can be used in an amount of 100 to 130 parts by weight per 100 parts by weight of polyol. To form polyurethane foam, it is preferable to use isocyanate in an amount of 100 parts by weight or more per 100 parts by weight of polyol, and to ensure low-temperature dimensional stability and prevent cracking of the polyurethane foam, it is preferable to use isocyanate in an amount of 130 parts by weight or less per 100 parts by weight of polyol.

[0051] The above isocyanate may be a polymethylenediphenyl diisocyanate (polymeric MDI) having 2.8 to 3.2 functional groups. The isocyanate index (NCO / OH ratio) of the above polymethylene polyphenyl diisocyanate is 50 to 150, and for example, it may be 100 to 130. When a compound having an isocyanate index in the above range is reacted with a polyol according to one embodiment of the present invention, the reactivity of the prepared rigid polyurethane foam is excellent, and the free foam density, thermal conductivity, compressive strength, and flame retardancy can be improved.

[0052] <Glass fiber composite insulation material> Furthermore, the glass fiber composite insulation material according to one embodiment of the present invention can be formed using the glass fiber reinforced polyurethane foam, thereby effectively ensuring the thermal insulation properties of the insulation material.

[0053] A method for preparing a glass fiber composite insulation material according to one embodiment of the present invention involves preparing the insulation material using the polyurethane foam described above, but a preparation method commonly used for preparing insulation materials can be applied.

[0054] In particular, the glass fiber composite insulation material of the present invention may be used as an insulation material for the preparation of liquefied gas storage tanks, liquefied gas cargo windows, and the like.

[0055] The glass fiber composite insulation material of the present invention is formed using polyurethane foam in which the thermal insulation properties and mechanical properties in cryogenic environments are effectively improved, and therefore, thermal insulation properties and mechanical properties in cryogenic environments can be effectively ensured in liquefied gas storage tanks.

[0056] The configuration and operation of the present invention will be described in more detail below through preferred embodiments of the present invention. However, these are presented as preferred examples of the present invention and should not be construed as limiting the present invention in any way.

[0057] Any information not included here can be technically reasoned upon by those skilled in this field, and therefore its explanation is omitted. [Examples]

[0058] Preparation Example 1-1: Preparation of Polyether Polyols In the steps prior to preparing the polyol premix composition, a polyether polyol was prepared. A polyether polyol was prepared by adding propylene oxide and ethylene oxide to sorbitol as an initiator. At this time, the hydroxyl group content of the sorbitol was adjusted to 450 mg KOH / g to 500 mg KOH / g.

[0059] Preparation Examples 1-2: Preparation of Isosorbide-Containing Polyols Isosorbide was condensed with an ester polyol via an esterification reaction to prepare an isosorbide-containing polyol. The isosorbide content was adjusted to 5-20% by weight of the ester polyol.

[0060] <Example 1> Example 1-1: Preparation of polyol premix composition A polyol premix composition was prepared by mixing 50 parts by weight of the above-mentioned polyether polyol, 40 parts by weight of polyester polyol, 10 parts by weight of isosorbide-containing polyol, and 100 parts by weight of the polyol component with 9 parts by weight of glass fiber, 8 parts by weight of a blowing agent (HCFO-1233zd), 0.1 parts by weight of catalysts (PC-5, PC-8), and a surfactant.

[0061] Examples 1-2: Preparation of glass fiber reinforced polyurethane foam A glass fiber reinforced polyurethane foam was prepared by stirring and foaming 110 parts by weight of polymethylene polyphenyl diisocyanate having 2.6 to 3.0 functional groups relative to 100 parts by weight of the polyol component in the above polyol premix composition.

[0062] Examples 1-3: Preparation of thermal insulation material An insulating material was prepared using the above-mentioned glass fiber reinforced polyurethane foam according to a conventional preparation method.

[0063] <Example 2> A polyol premix composition was prepared in the same manner as in Example 1, except that 20 parts by weight of isosorbide-containing polyol and 30 parts by weight of polyester polyol were used. Glass fiber reinforced polyurethane foam and thermal insulation material were prepared in the same manner as in Example 1.

[0064] <Example 3> A polyol premix composition was prepared in the same manner as in Example 1, except that 30 parts by weight of isosorbide-containing polyol and 20 parts by weight of polyester polyol were used. Glass fiber reinforced polyurethane foam and thermal insulation material were prepared in the same manner as in Example 1.

[0065] <Example 4> A polyol premix composition was prepared in the same manner as in Example 1, except that 40 parts by weight of isosorbide-containing polyol and 10 parts by weight of polyester polyol were used. Glass fiber reinforced polyurethane foam and thermal insulation material were prepared in the same manner as in Example 1.

[0066] <Example 5> A polyol premix composition was prepared in the same manner as in Example 1, except that 50 parts by weight of isosorbide-containing polyol were used instead of polyester polyol. Glass fiber reinforced polyurethane foam and thermal insulation material were prepared in the same manner as in Example 1.

[0067] <Example 6> A polyol premix composition was prepared in the same manner as in Example 1, except that 60 parts by weight of isosoid-containing polyol and 40 parts by weight of polyether polyol were used instead of polyester polyol. Glass fiber reinforced polyurethane foam and thermal insulation material were prepared in the same manner as in Example 1.

[0068] <Comparative Example 1> A polyol premix composition was prepared in the same manner as in Example 1, except that 70 parts by weight of isosoid-containing polyol and 30 parts by weight of polyether polyol were used instead of polyester polyol. Glass fiber reinforced polyurethane foam and thermal insulation material were prepared in the same manner as in Example 1.

[0069] <Comparative Example 2> A polyol premix composition was prepared in the same manner as in Example 1, except that 70 parts by weight of isosoid-containing polyol and 30 parts by weight of polyether polyol were used instead of polyester polyol. Glass fiber reinforced polyurethane foam and thermal insulation material were prepared in the same manner as in Example 1.

[0070] [Table 1]

[0071] <Example of experiment> The density, room temperature compressive strength, room temperature thermal conductivity, cryogenic tensile strength, cryogenic shear strength, raw solution impregnation properties, and CFM distribution diagrams of the glass fiber reinforced polyurethane foams prepared in Examples 1 to 6 and Comparative Examples 1 to 2 were measured, and the results are shown in Table 2 below.

[0072] [Table 2]

[0073] As shown in Table 2 above, compared to the polyurethane foam of Comparative Example 2, which was prepared using a polyol premix composition that does not contain isosoids, the polyurethane foams of Examples 1 to 6, which were prepared using a polyol premix composition that contains isosoids, showed improved mechanical properties and thermal conductivity at room temperature and cryogenic environments as the amount of isobaid increased.

[0074] However, in the case of the polyurethane foam in Comparative Example 1, as the amount of isosoid added increased to 70% by weight, the viscosity of the polyol composition increased. This resulted in problems with moldability (impregnation of the raw material and CFM distribution) during the preparation of the glass fiber composite insulation material, and ultimately, a decrease in the mechanical properties of the glass fiber composite insulation material was confirmed.

[0075] This confirmed that polyol premix compositions containing 10-60% by weight of isosoid-containing polyols can be used as glass fiber reinforced polyurethane foam and glass fiber composite insulation materials with improved thermal conductivity, tensile strength, and shear strength in cryogenic environments.

Claims

1. The material comprises polyols including polyether polyols, polyester polyols, and isosorbide-containing polyols, and glass fibers. The polyol contains the isosorbide-containing polyol in an amount of 10 to 60% by weight of the total weight of the polyol. Polyol premix composition for forming glass fiber reinforced polyurethane foam.

2. The polyol premix composition for forming glass fiber reinforced polyurethane foam according to claim 1, wherein the isosorbide-containing polyol has an acid value of 0.5 to 2.5 mg KOH / g, an average hydroxyl value of 250 mg KOH / g to 400 mg KOH / g, and an isosorbide content of 5 to 20% by weight of the ester polyol.

3. The polyol premix composition for forming glass fiber-reinforced polyurethane foam according to claim 1, wherein the glass fibers are a glass fiber mat laminate.

4. The glass fiber is contained in the composition in an amount of 7 to 25 parts by weight per 100 parts by weight of polyol, the polyol premix composition for forming glass fiber-reinforced polyurethane foam according to claim 1.

5. The product further contains a foaming agent, the foaming agent being HFC-245fa, HCFO-1233zd, HFO-1336mzz, cyclopentane, and CO ２ The polyol premix composition for forming glass fiber reinforced polyurethane foam according to claim 1, wherein the foaming agent is included in an amount of 0.5 to 30 parts by weight per 100 parts by weight of the polyol, and the foaming agent is one or more selected from the above, and the foaming agent is included in an amount of 0.5 to 30 parts by weight.

6. A glass fiber reinforced polyurethane foam prepared by reacting an isocyanate with a polyol premix composition for forming glass fiber reinforced polyurethane foam according to any one of claims 1 to 4.

7. The glass fiber reinforced polyurethane foam according to claim 6, wherein the isocyanate is a polymethylenediphenyl diisocyanate having 2.8 to 3.2 functional groups.

8. The glass fiber reinforced polyurethane foam according to claim 6, wherein the isocyanate is used in an amount of 100 to 130 parts by weight per 100 parts by weight of polyol.

9. A glass fiber composite insulation material comprising the glass fiber reinforced polyurethane foam described in claim 8.

10. A liquefied gas storage tank comprising the glass fiber composite insulation material described in claim 9.

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