Composition for producing silicone foam and silicone foam sheet

Abstract

The present invention relates to a composition for producing silicone foam, a foam sheet comprising the silicone foam produced therefrom, and a secondary battery module comprising the foam sheet, the composition comprising a silicone mixture, and the silicone mixture comprising: a first organopolysiloxane comprising an unsaturated hydrocarbon group; a second organopolysiloxane comprising a hydroxy group (Si-OH) of viscosity 35-120 cps; a third organopolysiloxane comprising a hydroxy group (Si-OH) of viscosity 3,000-6,000 cps; and a fourth organopolysiloxane comprising a hydrogen group (SiH).

Description

Composition for forming silicone foam and silicone foam sheet

[0001] The present invention relates to a composition for forming a silicone foam and a silicone foam sheet, and more specifically, to a composition for forming a low-density silicone foam, a silicone foam sheet comprising a silicone foam formed therefrom, and a secondary battery module comprising a silicone foam sheet.

[0002] In order to enhance the stability of pouch cells within secondary battery modules, a conventional method has been used in which urethane foam sheets are inserted between the cells to prevent cell swelling during charging.

[0003] However, while urethane foam sheets possess excellent compression recovery properties that allow for expansion control, they have low flame retardancy, which limits the potential for fire to easily spread to surrounding cells if a secondary battery cell ignites.

[0004] Although there have been attempts to use silicone foam sheets with excellent heat resistance to improve such flame retardancy issues, problems arose in which the silicone foam stabilizer did not function effectively during the manufacturing process of the silicone foam sheets, making it difficult to form the foam uniformly and resulting in reduced durability.

[0005] Accordingly, there is a growing need for silicone foam sheets that satisfy both heat resistance and stability suitable for secondary batteries.

[0006] The present invention provides a composition for forming a silicon foam that can act as a buffer between cells in a secondary battery module and has low density and low compressive strength.

[0007] In addition, the present invention provides a silicone foam formed from the above-described silicone foam forming composition.

[0008] In addition, the present invention provides a foamed sheet comprising the above-mentioned silicone foam.

[0009] In addition, the present invention provides a secondary battery module comprising the above-mentioned silicone foam sheet.

[0010]

[0011] The problems that the present invention aims to solve are not limited to the problem(s) mentioned above, and other unmentioned problems will be clearly understood by those skilled in the art from the description below.

[0012] To achieve the above objective, the present invention may provide a composition for forming a silicone foam comprising a silicone mixture, wherein the silicone mixture comprises: a first organopolysiloxane comprising an unsaturated hydrocarbon group; a second organopolysiloxane comprising a hydroxyl group (Si-OH) having a viscosity of 35 to 120 cps; a third organopolysiloxane comprising a hydroxyl group (Si-OH) having a viscosity of 3,000 to 6,000 cps; and a fourth organopolysiloxane comprising a hydrogen group (SiH).

[0013] The viscosity of the first organopolysiloxane above may be 50,000 to 80,000 cps.

[0014] The weight ratio of the second organopolysiloxane and the third organopolysiloxane may be 3 to 20: 80 to 97.

[0015] The total content of hydroxyl groups (Si-OH) in the above silicon mixture may be 0.12 to 0.2 mmol / g.

[0016] The hydrogen group (SiH) content of the above-mentioned fourth organopolysiloxane may be 14 mmol / g to 20 mmol / g.

[0017] The molar ratio of Si-Vi + Si-OH : SiH in the above silicon mixture may be 1:3 to 1:5.

[0018] Based on 100 parts by weight of the first organopolysiloxane, the second organopolysiloxane may comprise 3 to 20 parts by weight; the third organopolysiloxane may comprise 80 to 97 parts by weight; and the fourth organopolysiloxane may comprise 5 to 20 parts by weight.

[0019] The above composition for forming a silicone foam may further include at least one of 0.0001 to 0.05 parts by weight of a platinum catalyst; 20 to 80 parts by weight of a flame retardant; 1 to 10 parts by weight of hollow glass; and 0.1 to 20 parts by weight of a chain extender, based on 100 parts by weight of a total silicone mixture.

[0020]

[0021] In addition, the present invention may provide a silicone foam sheet comprising: a substrate layer; and a silicone foam layer formed from the aforementioned silicone foam forming composition located on at least one surface of the substrate layer.

[0022] The above substrate layer may be a film comprising at least one selected from the group consisting of PET (polyethylene terephthalate), PC (polycarbonate), PE (Polyethylene), PEN (Polyethylene naphthalate) and combinations thereof.

[0023] The density of the above silicone foam sheet is 0.25 to 0.45 g / cm³ 3 And the compressive strength (stress when compressed by 50% in the thickness direction) may be 40 kPa or less.

[0024]

[0025] In addition, the present invention can provide a secondary battery module comprising the aforementioned silicone foam sheet.

[0026] The composition for forming a silicone foam according to the present invention can provide a silicone foam with relatively low density and compressive strength by controlling the ratio of vinyl / hydroxyl groups within the silicone resin.

[0027] In addition, the composition for forming a silicone foam according to the present invention is manufactured in a liquid form, which not only provides excellent workability but also can provide a silicone foam having excellent flame retardancy and heat resistance after curing.

[0028] In addition, the silicone foam of the present invention has the effect of excellent productivity because a continuous process is possible by using a method of coating a liquid silicone foam-forming composition onto a substrate film.

[0029]

[0030] The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description of the invention or the claims.

[0031]

[0032] FIG. 1 illustrates a laminated structure of a foamed sheet according to one embodiment of the present invention.

[0033] FIG. 2 illustrates a laminated structure of a foamed sheet according to one embodiment of the present invention.

[0034] It should be noted that in the following description, only the parts necessary for understanding the embodiments of the present invention are described, and the description of other parts may be omitted to the extent that it does not detract from the gist of the present invention.

[0035] The terms and words used in the specification and claims described below should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention. Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely preferred embodiments of the invention and do not represent all aspects of the technical spirit of the invention; therefore, it should be understood that various equivalents and modifications capable of replacing them may exist at the time of filing this application.

[0036] In this specification, singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “comprising,” “comprising,” or “having” are intended to specify the existence of the implemented features, numbers, steps, components, or combinations thereof, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, components, or combinations thereof.

[0037] Where in this specification, when a quantity, concentration, or other value or parameter is given as an enumeration of a range, a preferred range, a preferred upper limit, and a preferred lower limit, it should be understood that any pair of any upper range limit or preferred value and any lower range limit or preferred value specifically discloses all ranges formed by any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether the range is disclosed separately.

[0038] Where a range of numerical values ​​is mentioned in this specification, unless otherwise stated, the range and the scope of the invention within that range are not intended to be limited to the specific values ​​mentioned when defining the range.

[0039] Throughout the specification, the same reference numerals refer to the same components. Additionally, in describing the present invention, detailed descriptions of related prior art are omitted if it is determined that such detailed descriptions would unnecessarily obscure the essence of the invention.

[0040] When the positional relationship between two parts is described using expressions such as 'on', 'on the upper', 'on the lower', or 'next to', one or more other parts may be located between the two parts unless 'immediately' or 'directly' is used.

[0041] In describing drawings, positional relationships such as 'top,' 'upper part,' 'upper surface,' 'lower part,' 'lower part,' and 'lower surface' are described based solely on the drawing and do not represent absolute positional relationships. In other words, depending on the observation location, the positions of 'top' and 'lower part,' or 'upper surface' and 'lower surface,' may be interchanged.

[0042]

[0043] The present invention will be described in detail below.

[0044] In one embodiment of the present invention, a composition for forming a silicone foam comprising a silicone mixture, wherein the silicone mixture comprises: a first organopolysiloxane comprising an unsaturated hydrocarbon group; a second organopolysiloxane comprising a hydroxyl group (Si-OH) having a viscosity of 35 to 120 cps; a third organopolysiloxane comprising a hydroxyl group (Si-OH) having a viscosity of 3,000 to 6,000 cps; and a fourth organopolysiloxane comprising a hydrogen group (SiH).

[0045]

[0046] In one embodiment, the first organopolysiloxane reacts with the fourth organopolysiloxane to form a three-dimensional network structure.

[0047] In one embodiment, the first organopolysiloxane may include at least two unsaturated hydrocarbon groups, for example, unsaturated hydrocarbon groups at both ends.

[0048] The above unsaturated hydrocarbon group may be a vinyl group, an allyl group, a butenyl group, a pentenyl group, or a hexenyl group, and specifically may be a vinyl group (Si-Vi).

[0049] In the present invention, the vinyl group may exist in a form bonded to a silicon atom (Si-Vi).

[0050] In one embodiment, the first organopolysiloxane undergoes an addition reaction with the fourth organopolysiloxane in the presence of the platinum catalyst to form a three-dimensional network structure, thereby having the effect of excellent elasticity.

[0051] Specifically, the Si-Vi group of the first organopolysiloxane and the Si-H group of the fourth organopolysiloxane react to form a Si-C bond, and the first organopolysiloxane molecule and the fourth organopolysiloxane molecule can cross-link with each other to form a three-dimensional network structure.

[0052] The first organopolysiloxane may be included in an amount of 20 to 70 weight percent based on 100 weight percent of the total silicone mixture. When the first organopolysiloxane is included in the above range, a cured structure with excellent mechanical strength and elasticity can be formed.

[0053] In one embodiment, the molecular weight of the first organopolysiloxane may be 20,000 to 150,000 g / mol.

[0054] In one embodiment, the viscosity (25°C) of the first organopolysiloxane may be 50,000 to 80,000 cps, 55,000 to 75,000, or 60,000 to 70,000.

[0055] In one embodiment, the content of the unsaturated hydrocarbon group, specifically the vinyl group (Si-Vi), of the first organopolysiloxane may be 0.1 to 0.05 mmol / g.

[0056] When the molecular weight, viscosity, and vinyl group content of the first organopolysiloxane satisfy the above numerical ranges, a cured structure with excellent mechanical strength and elasticity can be formed.

[0057] In one embodiment, the first organopolysiloxane may be one or more of the following types.

[0058] In one embodiment, the second organopolysiloxane reacts with the fourth organopolysiloxane to generate hydrogen gas and serves to form pores in the foam.

[0059] In one embodiment, the second organopolysiloxane may include hydroxyl groups (Si-OH) at both ends.

[0060] In the present invention, the hydroxyl group may exist in a form bonded to a silicon atom (Si-OH).

[0061] The second organopolysiloxane may be included in an amount of 3 to 20 parts by weight, 10 to 20 parts by weight, or 15 to 20 parts by weight, based on 100 parts by weight of the first organopolysiloxane. When the second organopolysiloxane is included within the above range, a foam having the low density desired in the present invention can be formed.

[0062] In one embodiment, the second organopolysiloxane can undergo a condensation reaction (dehydrogenation reaction) with the fourth organopolysiloxane in the presence of the platinum catalyst.

[0063] Specifically, the Si-OH group of the second organopolysiloxane and the Si-H group of the fourth organopolysiloxane can react to generate and release hydrogen (H2), thereby forming a siloxane (Si-O-Si) bond.

[0064] In one embodiment, the molecular weight of the second organopolysiloxane may be 2,000 to 120,000 g / mol.

[0065] In one embodiment, the viscosity (25°C) of the second organopolysiloxane may be 35 to 120 cps, 38 to 120 cps, 35 to 100 cps, 35 to 80 cps, 35 to 60 cps, or 35 to 50 cps.

[0066] In one embodiment, the content of the hydroxyl group (Si-OH) of the second organopolysiloxane may be 0.017 to 3 mmol / g.

[0067] If the molecular weight, viscosity, and hydroxyl group content of the second organopolysiloxane satisfy the above numerical ranges, a foam having the low density desired in the present invention can be formed.

[0068] In one embodiment, the third organopolysiloxane reacts with the fourth organopolysiloxane together with the aforementioned second organopolysiloxane to generate hydrogen gas and form pores of the foam.

[0069] In one embodiment, the third organopolysiloxane may include hydroxyl groups (Si-OH) at both ends.

[0070] The third organopolysiloxane may be included in an amount of 80 to 97 parts by weight, 80 to 90 parts by weight, or 80 to 85 parts by weight, based on 100 parts by weight of the first organopolysiloxane. When the third organopolysiloxane is included in the above range, a foam having the low density desired in the present invention can be formed.

[0071] In one embodiment, the third organopolysiloxane can undergo a condensation reaction (dehydrogenation reaction) with the fourth organopolysiloxane in the presence of the platinum catalyst.

[0072] Specifically, the Si-OH group of the third organopolysiloxane and the Si-H group of the fourth organopolysiloxane can react to produce and release hydrogen (H2), thereby forming a siloxane (Si-O-Si) bond.

[0073] In one embodiment, the molecular weight of the third organopolysiloxane may be 2,000 to 120,000 g / mol.

[0074] In one embodiment, the viscosity (25°C) of the third organopolysiloxane may be 3,000 to 6,000 cps, 3,200 to 5,900 cps, 3,500 to 5,800 cps, 3,700 to 5,700 cps, 4,000 to 5,600 cps, or 4,500 to 5,500 cps.

[0075] In one embodiment, the content of the hydroxyl group (Si-OH) of the third organopolysiloxane may be 0.01 to 2 mmol / g.

[0076] If the molecular weight, viscosity, and hydroxyl group content of the third organopolysiloxane satisfy the above numerical ranges, a foam having the low density desired in the present invention can be formed.

[0077] In one embodiment, a second organopolysiloxane containing hydroxyl groups (Si-OH) having 35 to 120 cps and a third organopolysiloxane containing hydroxyl groups (Si-OH) having 3000 to 6000 cps can be mixed and used. That is, by using two types of organopolysiloxanes containing hydroxyl groups (Si-OH) with different viscosities, a foaming effect and a three-dimensional network structure can be realized.

[0078] In one embodiment, the weight ratio of the second organopolysiloxane and the third organopolysiloxane may be 3 to 20:80 to 97, 10 to 20:80 to 90, or 15 to 20:80 to 85. When the second organopolysiloxane and the third organopolysiloxane are mixed in the above ratios, a foam having the low density and compressive strength desired in the present invention can be formed.

[0079] In one embodiment, by including the second organopolysiloxane and the third organopolysiloxane, the total content of hydroxyl groups (Si-OH) in the silicone mixture may be 0.12 to 0.2 mmol / g. When the total content of hydroxyl groups (Si-OH) satisfies the aforementioned numerical range, a foam having the low density desired in the present invention can be formed.

[0080] In the present invention, by using the first organopolysiloxane, the second organopolysiloxane, and the third organopolysiloxane within the aforementioned range, addition and condensation reactions occur simultaneously, and bubbles are generated by hydrogen gas, thereby forming a three-dimensional network and creating a uniform and robust porous structure.

[0081] On the other hand, if the addition reaction and the condensation reaction do not occur simultaneously and the addition reaction occurs first, the material hardens before pores are formed, preventing sufficient foaming; conversely, if the condensation reaction occurs first, bubbles caused by hydrogen gas may become too large or degass before hardening, potentially forming non-uniform pores.

[0082] In one embodiment, the fourth organopolysiloxane undergoes an addition reaction with the first organopolysiloxane to form a three-dimensional network structure, and undergoes a condensation reaction with the second and third organopolysiloxanes to generate hydrogen gas and form pores.

[0083] The above-mentioned fourth organopolysiloxane may include at least two hydrogen groups (SiH).

[0084] In the present invention, hydrogen groups may exist in a form bonded to silicon atoms (SiH). The fourth organopolysiloxane may be included in an amount of 5 to 20 parts by weight based on 100 parts by weight of the first organopolysiloxane. When the fourth organopolysiloxane is included in the above range, a uniform network structure is formed, resulting in excellent mechanical strength and elasticity, and a foaming amount capable of forming a foam with uniform pores and low density can be obtained.

[0085] In one embodiment, the molecular weight of the fourth organopolysiloxane may be 5,000 to 30,000 g / mol.

[0086] In one embodiment, the viscosity (25°C) of the fourth organopolysiloxane may be 20 to 500 cps.

[0087] In one embodiment, the content of hydrogen groups (SiH) of the fourth organopolysiloxane may be 14 mmol / g to 20 mmol / g.

[0088] When the molecular weight, viscosity, and hydrogen group content of the fourth organopolysiloxane satisfy the above numerical ranges, it can form a three-dimensional network structure by undergoing an addition reaction with the first organopolysiloxane, and form pores by generating hydrogen gas through a condensation reaction with the second organopolysiloxane and the third organopolysiloxane.

[0089] In one embodiment, one or more of the fourth organopolysiloxanes may be used.

[0090] In one embodiment, when the unsaturated hydrocarbon group of the first organopolysiloxane is a vinyl group, the molar ratio of Si-Vi + Si-OH : SiH of the silicone mixture may be 1:3 to 1:5. For example, when the total number of moles of Si-Vi and Si-OH is 1, the number of moles of SiH may be 3 to 5. When the molar ratio of Si-Vi + Si-OH : SiH satisfies the above ratio, over-foaming and changes over time can be prevented, and curing can be performed well to achieve the desired foaming effect.

[0091] In one embodiment, the composition for forming the silicone foam may further include at least one of a platinum catalyst, a flame retardant, hollow glass, and a chain extender.

[0092] In one embodiment, the platinum catalyst is Pt(C5H7O2)2, (CH3C5H4)Pt(CH3)3, platinum halide (H2PtCl6·6H2O, etc.), platinum-olefin complex, platinum-alcohol complex, platinum-alcoolat complex, platinum-ether complex, platinum-aldehyde complex, platinum-ketone complex, platinum vinylsiloxane complex (platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex), bis-(γ-picoline)-platinum dichloride, trimethylenedipyridine-platinum dichloride, dicyclopentadiene-platinum dichloride, cyclooctadiene-platinum dichloride, cyclopentadiene-platinum dichloride), bis(alkynyl)bis(triphenylphosphine)platinum complex, It may include at least one selected from the group consisting of bis(alkenyl)(cyclooctadiene)platinum complexes and combinations thereof, specifically Pt(C5H7O2)2.

[0093] The above platinum catalyst may be included in an amount of 0.0001 to 0.05 parts by weight based on 100 parts by weight of the silicon mixture. When the platinum catalyst is included in the above range, the addition reaction and condensation reaction by photocuring or thermal curing proceed together, thereby improving productivity by curing simultaneously with foaming.

[0094] The above-mentioned silicone foam forming composition includes the platinum catalyst, so that no dark reaction occurs at room temperature, and thus has the effect of excellent storage stability even without including a curing retardant.

[0095] In one embodiment, the flame retardant may include at least one selected from the group consisting of aluminum hydroxide, magnesium hydroxide, barium hydroxide, zirconium hydroxide, magnesium carbonate, calcium carbonate, tin oxide, aluminum oxide, zinc borate, dolomite, hydrotalcite, wollastonite, silica, fluorine-based flame retardants, platinum flame retardants, and combinations thereof.

[0096] The flame retardant may be included in an amount of 20 to 80 parts by weight based on 100 parts by weight of the silicone mixture. When the flame retardant is included in the above range, it can be uniformly dispersed in the silicone mixture, a uniform coating film can be obtained after coating on the substrate film, and flame retardancy can be further improved.

[0097] In one embodiment, the average particle size (D50) of the hollow glass may be 50 μm or more and 70 μm or less. In addition, the density of the hollow glass is 0.3 g / cm³ 3 Less than or equal to 0.1 to 0.3 g / cm³ 3 It may be less than or equal to the above. When using hollow glass having the above average particle size range and density, bubbles generated by the curing reaction can be trapped between the hollow glass, preventing excessive growth of bubbles (pores), and a uniform bubble formation effect can be obtained.

[0098] The above hollow glass may be included in an amount of 1 to 10 parts by weight or 1 to 5 parts by weight based on 100 parts by weight of the silicon mixture. When the hollow glass is included in the above range, bubbles generated by the curing reaction can be trapped between the hollow glass, preventing excessive growth of bubbles (pores), and a saturating effect can be obtained to form bubbles (pores) of a uniform size.

[0099] In one embodiment, the chain extender reacts with the first organopolysiloxane, the second organopolysiloxane, or the third organopolysiloxane to extend the polymer chain, thereby increasing mechanical strength, elasticity, and flexibility.

[0100] In one embodiment, the chain extender may include hydrogen groups (SiH) at both ends.

[0101] The above chain extender may be included in an amount of 0.1 to 20 weight percent based on 100 weight percent of the total silicone mixture. When the chain extender is included in the above range, the polymer chain can be extended without hindering curing.

[0102] In one embodiment, the molecular weight of the chain extender may be 3,500 to 30,000 g / mol.

[0103] In one embodiment, the viscosity (25°C) of the chain extender may be 30 to 1,000 cps.

[0104] In one embodiment, the content of hydrogen groups (SiH) of the chain extender may be 0.07 to 2.0 mmol / g.

[0105] In one embodiment, the viscosity of the silicone foam forming composition may be 20,000 to 150,000 cps, or 57,000 to 72,000 cps.

[0106] The above-mentioned silicone foam forming composition is in a liquid form, and can be easily coated onto a substrate layer described later.

[0107]

[0108] In one embodiment of the present invention, a silicone foam sheet is provided comprising: a substrate layer; and a silicone foam layer formed from a composition for forming a silicone foam located on at least one surface of the substrate layer.

[0109] FIG. 1 schematically illustrates a silicone foam sheet (100) comprising: a substrate layer (110) according to one embodiment of the present invention; and a silicone foam layer (120) coated on at least one surface of the substrate layer (110). Referring to FIG. 1, the structure may have a silicone foam layer (120) laminated on one surface of the substrate layer (110).

[0110] FIG. 2 schematically illustrates a silicone foam sheet (200) comprising a substrate layer (210) according to one embodiment of the present invention; a silicone foam layer (220) coated on at least one surface of the substrate layer (210); and a substrate layer (210) located on the other surface of the silicone foam layer where the substrate layer is located. Referring to FIG. 2, the structure may have a substrate layer (210) laminated on both sides of the silicone foam layer (220).

[0111] In one embodiment, the silicone foam sheet may mean that, as necessary, the substrate layer is peeled off and only the silicone foam layer is included.

[0112] In one embodiment, the silicone foam layer can act as a cushioning member and preferably has impact resistance and compression resistance.

[0113] The above silicone foam may be formed from the aforementioned silicone foam forming composition, and details that overlap with the above are omitted.

[0114] In one embodiment, the silicone foam layer may be formed in a structure in which a plurality of foam layers are laminated to simultaneously exhibit excellent impact resistance and compression resistance effects.

[0115] The above silicone foam has a low density, so it can avoid significantly increasing the weight of the secondary battery and achieve lightweighting of the battery module.

[0116] In one embodiment, the thickness of the silicone foam layer may be 0.5 to 5 mm, 0.6 to 4.5 mm, 0.7 to 4 mm, 0.8 to 3.5 mm, 0.9 to 3 mm, or 1 to 2.5 mm. When the thickness of the silicone foam layer is formed within the above range, the force against external impact or swelling can be effectively dispersed.

[0117] In one embodiment, the density is 0.25 to 0.45 g / cm³ 3 The compressive strength (stress when compressed by 50% in the thickness direction) is 40 kPa or less, and the vertical flame retardancy may be UL94 V-0.

[0118] The average length of the pores in the above silicone foam layer may be 800 µm or less.

[0119] In one embodiment, the substrate layer may be laminated on one or both sides of the silicone foam layer.

[0120] The above substrate layer may be a film comprising at least one selected from the group consisting of PET (polyethylene terephthalate), PC (polycarbonate), PE (Polyethylene), PEN (Polyethylene naphthalate) and combinations thereof, and specifically may be a film made of PET.

[0121] In one embodiment, the thickness of the substrate layer may be 25 to 150 mm. When the thickness of the substrate layer is formed within this range, the foam layer can be sufficiently supported without increasing the compressive strength.

[0122]

[0123] In one embodiment, the silicone foam sheet exhibits excellent properties regarding heat resistance and flame retardancy, and demonstrates excellent effects in terms of module reliability when applied to a secondary battery.

[0124] In one embodiment of the present invention, the silicone foam sheet is,

[0125] (a) A step of preparing a foaming agent liquid;

[0126] (b) a step of coating a foaming liquid on one surface of at least one substrate layer;

[0127] (c) a step of curing a foaming agent coated on one side of at least one substrate layer to form a silicone foam layer to produce a foamed sheet; can be manufactured by a roll-to-roll (R2R) coating method including the step of producing a foamed sheet.

[0128] In step (a) above, the foaming liquid may be the aforementioned silicone foam forming composition, and details that overlap with the above are omitted.

[0129] In step (B) above, the foaming liquid can be applied to one surface of the substrate layer using a roll coater. The roll coater can be a comma coater, a slot die coater, a rip coater, etc.

[0130] In one embodiment, the foaming liquid (e.g., foaming layer) coated on one side of the substrate layer may further include a separate substrate layer (hereinafter also referred to as an "upper substrate layer") on the other side.

[0131] In step (c) above, the composition for forming the silicone foam can form a silicone foam by photocuring or thermal curing.

[0132] Specifically, the substrate coated with the foaming agent liquid can be transferred to a heat curing chamber or a photocuring chamber, and foaming can occur simultaneously with curing by active energy (heat or light irradiation) to form a foam on the substrate layer. Next, the upper substrate layer can be peeled off and wound to be processed into a roll, or cut to a specific size to be manufactured into a sheet. The process from coating to roll winding or sheet formation is carried out as a continuous process to achieve high productivity.

[0133] The above silicone foam forming composition includes a first organopolysiloxane containing unsaturated hydrocarbon groups and a second organopolysiloxane and a third organopolysiloxane containing hydroxyl groups with different viscosities, and can improve productivity by simultaneously utilizing a condensation reaction (dehydrogenation reaction) and an addition reaction to expand and cure simultaneously.

[0134] Specifically, hydrogen gas molecules generated by the dehydrogenation reaction gather to form gas bubbles, and as they harden, they can form a silicone foam.

[0135] In one embodiment, the curing is performed by thermal curing at a temperature of 100 to 150°C or 2,000 mJ / cm² 2 Up to 10,000 mJ / cm 2 It may be photocorrected with the amount of light.

[0136]

[0137] In the above photocuring, the irradiation light source can be selected from microwaves, infrared rays, visible light, ultraviolet rays, X-rays, and γ-rays, as well as α-particle beams, proton beams, neutron beams, and electron beams.

[0138]

[0139] In one embodiment of the present invention, a secondary battery module comprising a silicon foam sheet is provided.

[0140] In one embodiment, the silicone foam sheet is the silicone foam sheet described above, and details that overlap with the description above are omitted.

[0141] In one embodiment, the silicone foam sheet included in the secondary battery module acts as a pad for cushioning within the secondary battery module to control swelling of the cell and prevent damage to the cell or module due to cell expansion.

[0142] The above secondary battery module includes the above silicon foam layer and has excellent vibration absorption and repulsion force due to compression, thereby providing a secondary battery module with excellent dimensional stability even if cell swelling occurs.

[0143] In one embodiment, the silicone foam sheet effectively adheres the substrate layer and the silicone foam layer without including a separate adhesive between the layers, and even after combustion, the layers remain adhered without falling off, thereby providing a secondary battery module with excellent structural stability.

[0144]

[0145] The above description explains the technical concept of the present invention using one embodiment, and those skilled in the art to which the present invention pertains will be able to make various modifications and variations within the scope of the essential characteristics of the present invention. Accordingly, the embodiments described in this invention are intended to explain, not limit, the technical concept of the present invention, and the scope of the technical concept of the present invention is not limited by such embodiments. The scope of protection of the present invention shall be interpreted by the claims, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of the present invention.

[0146]

[0147] <Examples and Comparative Examples>

[0148] A composition for forming a silicone foam was prepared by mixing the first organopolysiloxane, the second organopolysiloxane, the third organopolysiloxane, and the fourth organopolysiloxane in the amounts shown in Table 1 below.

[0149] Subsequently, a silicone foam-forming composition was coated to a thickness of 0.5 mm between two PET films (XD500P 50 µm) using a roll-to-roll coating method, and a foam sheet was manufactured by irradiating a blacklight lamp from above and below for 4 minutes. At this time, the thickness of the manufactured foam sheet was 1.9 mm.

[0150] Example 1 Example 2 Example 3 Example 4 Example 5 Example 61) 1001001001001001002) 1515152020103) 8585858080904) 79109115.5OH Molar mass (mmol / g) 0.130.130.130.170.170.1Si-H / (Si-Vi+Si-OH) molar ratio 3.34.34.83.54.33.31) 1st organopolysiloxane: viscosity is 65,000 cps and vinyl group (SiVi) content is 0.03 mmol / g2) 2nd organopolysiloxane: viscosity is 45 cps and hydroxyl group (SiOH) content is 2.5 mmol / g3) 3rd organopolysiloxane: 4) 4th organopolysiloxane: viscosity 5000 cps and hydroxyl (SiOH) content 0.07 mmol / g

[0151]

[0152] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 1) 100 100 100 100 100 100 100 2) 15 20 11 13 0 30 3) 8 5 80 99 99 99 70 70 4) 21 26 1 1.5 41 7 18 OH Molar mass (mmol / g) 0.1 3 0.1 7 0.0 4 0.0 4 0.0 4 0.0 4 0.0 4 Si-H / (Si-Vi+Si-OH) molar ratio 10 10 1.3 1.8 5.2 4.8 5.2 1) First organopolysiloxane: viscosity is 65,000 cps and vinyl group (SiVi) content is 0.03 mmol / g 2) Second organopolysiloxane: viscosity is 45 cps and hydroxyl group (SiOH) 3) 3rd organopolysiloxane: viscosity of 5000 cps, hydroxyl (SiOH) content of 0.07 mmol / g 4) 4th organopolysiloxane: viscosity of 20 cps, hydrogen (SiH) content of 15.0 mmol / g

[0153]

[0154] Comparative Example 8 Comparative Example 9 Comparative Example 10 Comparative Example 11 Comparative Example 12 Comparative Example 13 Comparative Example 14 1) 100 100 100 100 100 100 100 2) 55 55 15 20 3) 95 95 95 95 95 85 80 4) 3.4 3.8 5.2 5.5 11.5 67.5 OH Molar Mass (mmol / g) 0.07 0.07 0.07 0.07 0.07 0.13 0.17 Si-H / (Si-Vi+Si-OH) Molar Ratio 2.9 3.3 4.3 4.8 10 2.9 2.9 1) First organopolysiloxane: viscosity is 65,000 cps and vinyl group (SiVi) content is 0.03 mmol / g 2) Second organopolysiloxane: viscosity is 3) Third organopolysiloxane: viscosity of 45 cps and hydroxyl (SiOH) content of 2.5 mmol / g 4) Fourth organopolysiloxane: viscosity of 5000 cps and hydroxyl (SiOH) content of 0.07 mmol / g

[0155]

[0156] Comparative Example 15 Comparative Example 16 1)100 1)-1 -100 2)15 20 3)85 80 4)-9 4)-17-OH Molar mass (mmol / g) 0.13 0.17 Si-H / (Si-Vi+Si-OH) molar ratio 3.3 150 1) First organopolysiloxane: viscosity 65,000 cps, vinyl group (SiVi) content 0.03 mmol / g 1)-1 First organopolysiloxane: viscosity 10,000 cps, vinyl group (SiVi) content 0.03 mmol / g 2) Second organopolysiloxane: viscosity 45 cps, hydroxyl group (SiOH) content 2.5 mmol / g 3) Third organopolysiloxane: viscosity 5,000 cps, hydroxyl group (SiOH) content 0.07 mmol / g4) Quaternary organopolysiloxane: viscosity 20 cps and hydrogen group (SiH) content 15.0 mmol / g4)-1 Quaternary organopolysiloxane: viscosity 20 cps and hydrogen group (SiH) content 10.0 mmol / g

[0157]

[0158] <Experimental Example>

[0159] Verification of foam sheet physical properties

[0160] The physical properties of the silicone foam sheets prepared in the above examples and comparative examples were measured, and the results are shown in Tables 5 to 8 below.

[0161] - Foam sheet density (g / cm²) 3 Measurement: The weight of a specimen measuring 100 x 100 mm is measured using a precision balance, and the measurement is obtained by dividing the weight by the volume calculated from the thickness and area of ​​the aforementioned foam sheet. The density is 0.4 g / cm³. 3 If it is below this level, low compressive strength can be obtained.

[0162] - CFD (Compression Force Deflection) measurement: Using a Universal Testing Machine, specimens (50 mm x 50 mm) were stacked to a thickness of 4 mm and compressed at a speed of 8 mm / min to measure the compressive strength according to the compression ratio. When the compressive strength is 300 kPa or less when compressed by 50%, it can effectively buffer the expansion of the secondary battery cell.

[0163]

[0164] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Foamed sheet density (g / cm³) 3 )0.310.30.310.30.330.33CFD 50% (kPa)25272713.52435

[0165]

[0166] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Foam sheet density (g / cm²) 3 ) Overcured Overcured Undercured 0.4 9 0.5 2 0.5 1 0.5 CFD 50%(kPa)- -- 126 228 111 342

[0167]

[0168] Comparative Example 8 Comparative Example 9 Comparative Example 10 Comparative Example 11 Comparative Example 12 Comparative Example 13 Comparative Example 14 Foam sheet density (g / cm²) 3 )0.480.440.390.390.390.370.33CFD 50%(kPa)8186811031148147

[0169]

[0170] Comparative Example 15 Comparative Example 16 Foam sheet density (g / cm²) 3 )Insufficient hardening 0.37CFD 50%(kPa)-150

[0171]

[0172] Referring to Tables 5 to 8 above, when a silicone foam sheet is manufactured using the silicone foam-forming composition prepared in Examples 1 to 6, the density of the silicone foam sheet is 0.25 g / cm³ 3Up to 0.45 / cm 3 At the same time, it was confirmed that the physical properties of the foam sheet are excellent, with a compressive strength of 40 kPa or less at a compression ratio of 50%.

[0173] On the other hand, it was confirmed that the physical properties of the foamed sheets in Comparative Examples 1 to 16 were inferior.

[0174]

[0175] Although the present invention has been described above with reference to embodiments, the present invention is not limited by the embodiments disclosed in this specification, and it is obvious that various modifications can be made by a person skilled in the art within the scope of the technical concept of the present invention. Furthermore, even if the effects of the configuration of the present invention were not explicitly described while describing the embodiments of the present invention above, it is natural to acknowledge that the effects predictable by said configuration should also be recognized.

[0176] 100, 200: Foam sheet

[0177] 110, 210: Record layer

[0178] 120, 220: Silicone foam layer

Claims

1. A composition for forming a silicone foam comprising a silicone mixture, The above silicone mixture is a first organopolysiloxane containing unsaturated hydrocarbon groups; A second organopolysiloxane comprising a hydroxyl group (Si-OH) having a viscosity of 35 to 120 cps; A third organopolysiloxane comprising a hydroxyl group (Si-OH) having a viscosity of 3,000 to 6,000 cps; and A composition for forming a silicone foam comprising a fourth organopolysiloxane containing a hydrogen group (SiH).

2. In Paragraph 1, A composition for forming a silicone foam, wherein the viscosity of the first organopolysiloxane is 50,000 to 80,000 cps.

3. In Paragraph 1, A composition for forming a silicone foam, wherein the weight ratio of the second organopolysiloxane and the third organopolysiloxane is 3 to 20: 80 to 97.

4. In Paragraph 1, A composition for forming a silicone foam, wherein the total content of hydroxyl groups (Si-OH) of the above silicone mixture is 0.12 to 0.2 mmol / g.

5. In Paragraph 1, A composition for forming a silicone foam, wherein the hydrogen group (SiH) content of the above-mentioned fourth organopolysiloxane is 14 mmol / g to 20 mmol / g.

6. In Paragraph 1, A composition for forming a silicon foam, wherein the molar ratio of Si-Vi + Si-OH : SiH of the above silicon mixture is 1:3 to 1:

5.

7. In Paragraph 1, Based on 100 parts by weight of the first organopolysiloxane above, The second organopolysiloxane is 3 to 20 parts by weight; The third organopolysiloxane is 80 to 97 parts by weight; and A composition for forming a silicone foam comprising 5 to 20 parts by weight of the fourth organopolysiloxane.

8. In Paragraph 1, The above silicone foam-forming composition is based on a total of 100 parts by weight of the silicone mixture, 0.0001 to 0.05 parts by weight of platinum catalyst; 20 to 80 parts by weight of flame retardant; 1 to 10 parts by weight of hollow glass; and A composition for forming a silicone foam, further comprising at least one of 0.1 to 20 parts by weight of a chain extender.

9. Substrate layer; and A silicone foam sheet comprising: a silicone foam layer formed from a silicone foam forming composition according to claim 1 located on at least one surface of the above-mentioned substrate layer.

10. In Paragraph 9, The above substrate layer is a silicone foam sheet comprising at least one film selected from the group consisting of PET (polyethylene terephthalate), PC (polycarbonate), PE (Polyethylene), PEN (Polyethylene naphthalate), and combinations thereof.

11. In Paragraph 9, The density of the above silicone foam sheet is 0.25 to 0.45 g / cm³ 3 A silicone foam sheet having a compressive strength (stress when compressed by 50% in the thickness direction) of 40 kPa or less.

12. A secondary battery module comprising a silicone foam sheet according to paragraph 1.

Images