Crosslinking agent composition for olefin copolymer, encapsulant composition for optical element containing the same, and encapsulant film for optical element

Abstract

The present invention relates to a crosslinking agent composition for an olefin copolymer, a sealing material composition for an optical element, a sealing material film for an optical element, and an optoelectronic device. By applying the compound of Chemical Formula 1 as a crosslinking aid to the crosslinking agent composition for an olefin copolymer or the sealing material composition for an optical element containing an olefin copolymer, excellent productivity can be exhibited, and a sealing material composition for an optical element and a sealing material film for an optical element having a high volume resistivity and a high light transmittance can be produced.

Description

Technical Field

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0085134 filed on July 11, 2022, and all the contents disclosed in the document of the Korean patent application are incorporated herein by reference in their entirety.

[0002] The present invention relates to a crosslinking agent composition for an olefin copolymer, a sealing material composition for an optical element containing the same, and a sealing material film for an optical element. More specifically, the present invention relates to a crosslinking agent composition for an olefin copolymer used in a sealing material composition for an optical element containing an olefin copolymer, a sealing material composition for an optical element containing the crosslinking agent, a sealing material film for an optical element manufactured using the same, and an optical element module including the sealing material film for an optical element.

Background Art

[0003] As global environmental problems and energy problems are becoming increasingly serious, solar cells are attracting attention as a clean and non-depleting energy generation means. When solar cells are used outdoors, such as on the roofs of buildings, they are generally used in the form of modules. When manufacturing a crystalline solar cell module, in order to obtain a crystalline solar cell module, a solar cell module protection sheet (front-side transparent protection member) / solar cell encapsulant / crystalline solar cell element / crystalline solar cell element / solar cell encapsulant / solar cell module protection sheet (back-side protection member) are laminated in this order. On the other hand, in order to obtain a thin-film solar cell module, a thin-film solar cell element / solar cell encapsulant / solar cell module protection sheet (back-side protection member) are laminated in this order.

[0004] Generally, as the aforementioned solar cell encapsulant, ethylene / vinyl acetate copolymer, ethylene / α-olefin copolymer, etc. are used. In addition, since long-term weather resistance is required for the solar cell encapsulant, a light stabilizer is usually included as an additive. Also, in consideration of the adhesion to the front-side transparent protection member or the back-side protection member typified by glass, a silane coupling agent is usually included in the solar cell encapsulant.

[0005] Specifically, ethylene / vinyl acetate copolymer (EVA) sheets are widely used because they are excellent in transparency, flexibility, adhesiveness, etc. Ethylene-vinyl acetate copolymer (EVA) films are widely used because they are excellent in transparency, flexibility, adhesiveness, etc. However, when an EVA composition is used as a constituent material of a solar cell encapsulant, there has been concern that components such as acetic acid gas generated by the decomposition of EVA may affect the solar cell element.

[0006] Ethylene / α-olefin copolymer has no problem of resin hydrolysis, so it has been able to solve the problems of reduced lifespan and reliability. However, since ethylene / α-olefin copolymer does not contain a polar group in the resin, its miscibility with a polar crosslinking aid contained as a constituent material of a conventional solar cell encapsulant decreases, and it takes a very long time for impregnation, so there has been a problem in productivity.

[0007] Thus, in a situation where it is necessary to develop a crosslinking aid that can improve the productivity of a solar cell encapsulant containing an ethylene / α-olefin copolymer, which is excellent in volume resistivity and useful as a substance requiring high insulation such as a solar cell encapsulant.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0009] The problem to be solved by the present invention is to provide a crosslinking agent composition for an olefin-based copolymer, which contains a crosslinking aid having excellent miscibility with an olefin-based copolymer and is used for crosslinking the olefin-based copolymer.

[0010] Another problem to be solved by the present invention is to provide a sealing material composition for an optical element that contains a crosslinking aid having excellent miscibility with an olefin copolymer and exhibits a high volume resistivity and thus excellent insulation properties.

[0011] Another problem to be solved by the present invention is to provide a sealing material film for an optical element manufactured using the above-described sealing material composition for an optical element. Yet another problem to be solved by the present invention is to provide an optoelectronic device including the above-described sealing material film for an optical element.

Means for Solving the Problems

[0012] To solve the above problems, the present invention provides a crosslinking agent composition for an olefin copolymer, a sealing material composition for an optical element, a sealing material film for an optical element, and an optoelectronic device. [1] The present invention provides a crosslinking agent composition for an olefin copolymer containing a compound of the following Chemical Formula 1.

[0013]

Chemical Formula

[0014] [2] In the present invention, there is provided the crosslinking agent composition for an olefin copolymer according to [1] above, wherein R1 to R4 are each independently an alkenyl having 2 to 8 carbon atoms, and m is an integer of 1 to 12.

[0015] [3] In the present invention, there is provided the crosslinking agent composition for an olefin copolymer according to [1] or [2] above, wherein R1 to R4 are each independently an alkenyl having 2 to 8 carbon atoms having a double bond at the terminal.

[0016] [4] In the present invention, there is provided a crosslinking agent composition for an olefin copolymer according to any one of [1] to [3], wherein the crosslinking aid compound of Chemical Formula 1 is 3-(triallylsilyl)propyl acrylate.

[0017] [5] The present invention provides a crosslinking agent composition for an olefin copolymer according to [4], further comprising a second crosslinking aid compound other than the crosslinking aid compound of Chemical Formula 1.

[0018] [6] In the present invention, there is provided a crosslinking agent composition for an olefin copolymer according to [5], wherein the weight ratio of the crosslinking aid compound of Chemical Formula 1 to the second crosslinking aid compound is 1:0.2 to 1:9.

[0019] [7] In the present invention, there is provided a crosslinking agent composition for an olefin copolymer according to [5] or [6], wherein the second crosslinking aid compound comprises one or more selected from the group consisting of triallyl isocyanurate, triallyl cyanurate, diallyl phthalate, diallyl fumarate, diallyl maleate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, and trimethylolpropane trimethacrylate.

[0020] [8] In the present invention, there is provided a crosslinking agent composition for an olefin copolymer according to any one of [1] to [7], wherein the crosslinking agent is one or more selected from the group consisting of organic peroxides, hydroperoxides, and azo compounds.

[0021] [9] In the present invention, the crosslinking agent is one or more selected from the group consisting of t-butyl cumyl peroxide, di-t-butyl peroxide, di-cumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexyne, cumene hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethyl-2,5-di(hydroperoxy)hexane, t-butyl hydroperoxide, bis-3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, benzoyl peroxide, o-methylbenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, t-butyl peroxyisobutyrate, t-butyl peroxyacetate, t-butyl peroxy-2-ethylhexyl carbonate (TBEC), t-butyl peroxy-2-ethylhexanoate, t-butyl peroxypivalate, t-butyl peroxyoctoate, t-butyl peroxyisopropyl carbonate, t-butyl peroxybenzoate, di-t-butyl peroxyphtalate, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, 2,5-dimethyl-2,5-di(benzoylperoxy)-3-hexyne, methyl ethyl ketone peroxide, cyclohexanone peroxide, azobisisobutyronitrile, and azobis(2,4-dimethylvaleronitrile), and provides a crosslinking agent composition for an olefin copolymer according to any one of the above [1] to [8].

[0022]

[10] In the present invention, the silane coupling agent is one or more selected from the group consisting of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, and p-styryltrimethoxysilane, and provides a crosslinking agent composition for an olefin copolymer according to any one of [1] to [9] above.

[0023]

[11] The present invention provides a sealing material composition for an optical element, comprising an olefin copolymer and a crosslinking agent composition for an olefin copolymer according to any one of [1] to

[10] above.

[0024]

[12] In the present invention, the olefin copolymer is an ethylene α-olefin copolymer, and provides a sealing material composition for an optical element according to

[11] above.

[0025]

[13] The present invention provides a sealing material film for an optical element, comprising an olefin copolymer and a structure derived from a compound of the following Chemical Formula 1.

[0026]

Chemical Formula

[0027]

[14] The present invention provides an optoelectronic device, comprising an optical element and a sealing material film for an optical element according to

[13] above.

Advantages of the Invention

[0028] The crosslinking agent composition for olefin copolymers of the present invention contains, as a crosslinking aid, a compound having excellent miscibility with olefin copolymers, rapidly impregnates olefin copolymers, and the encapsulant composition for optical elements produced using the same exhibits excellent volume resistivity and light transmittance, and thus can be widely used for various applications in the electric and electronic industries.

Embodiments for Carrying Out the Invention

[0029] Hereinafter, the present invention will be described in more detail so that the present invention can be easily understood. Terms and words used in the description and claims of the present invention should not be construed as being limited to their ordinary or dictionary meanings. The inventors should interpret them in accordance with the meanings and concepts consistent with the technical idea of the present invention, based on the principle that they can appropriately define the concepts of the terms in order to explain their invention in the best way.

[0030] Specific descriptions of each substituent defined in this specification are as follows. As used in this specification, the term "alkyl" means a linear or branched hydrocarbon residue, unless otherwise specified.

[0031] As used in this specification, the term "alkenyl" means a linear or branched alkenyl group, unless otherwise specified. The branched chain may be alkyl having 1 to 20 carbon atoms; or alkenyl having 2 to 20 carbon atoms.

[0032] [Crosslinking Agent Composition for Olefin Copolymers] The crosslinking agent composition for olefin copolymers of the present invention contains a crosslinking agent, a silane coupling agent, and a crosslinking aid compound represented by the following Chemical Formula 1.

[0033] [Chemical Formula] In Chemical Formula 1, R1 to R4 are each independently alkyl having 1 to 20 carbon atoms or alkenyl having 2 to 20 carbon atoms, and m is an integer of 1 to 20.

[0034] In addition, in Chemical Formula 1, R1 to R4 may each independently be an alkenyl group having 2 to 8 carbon atoms, and m may be an integer of 1 to 12. In addition, in Chemical Formula 1, R1 to R4 may each independently be an alkenyl group having 2 to 8 carbon atoms and having a double bond at the terminal.

[0035] In addition, the crosslinking agent composition for an olefin copolymer according to an embodiment of the present invention may specifically contain 3-(triallylsilyl)propyl acrylate represented by the following Chemical Formula 2 as the compound of Chemical Formula 1.

[0036]

Chemical Formula

[0037] The compound of Chemical Formula 1 contained in the crosslinking agent composition for an olefin copolymer of the present invention may be contained as a crosslinking aid in the crosslinking agent composition for an olefin copolymer. The compound of Chemical Formula 1 exhibits excellent miscibility with the olefin copolymer and can exhibit a fast impregnation rate. As a result, among the crosslinking agent, silane coupling agent, and crosslinking aid contained in the crosslinking agent composition used for a conventional olefin copolymer, by improving the absorption rate of the crosslinking aid that exhibits the slowest absorption rate with respect to the olefin copolymer, it is possible to show the effect of shortening the impregnation time of the crosslinking agent composition, achieve a short impregnation time, and exhibit excellent crosslinked physical properties with respect to the olefin copolymer.

[0038] When the crosslinking agent composition for an olefin copolymer of the present invention containing the compound of Chemical Formula 1 is applied as a crosslinking agent to a sealing material composition for an optical element containing an olefin copolymer, the sealing material composition for an optical element can exhibit a high degree of crosslinking, volume resistivity, and light transmittance.

[0039] In addition, the crosslinking agent composition for the olefin copolymer may further contain a second crosslinking aid compound other than the compound of Chemical Formula 1 as a crosslinking aid. As the second crosslinking aid, various crosslinking aids known in the art may be used. For example, compounds containing at least one or more unsaturated groups such as allyl groups or (meth)acryloxy groups may be included.

[0040] The second crosslinking aid may be a crosslinking aid containing at least one or more unsaturated groups. For example, polyallyl compounds such as triallyl isocyanurate (TAIC), triallyl cyanurate, diallyl phthalate, diallyl fumarate, or diallyl maleate may be mentioned. Compounds containing the (meth)acryloxy group include, for example, poly(meth)acryloxy compounds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate, and trimethylolpropane trimethacrylate, but are not particularly limited thereto.

[0041] When the crosslinking aid composition for the olefin copolymer according to an embodiment of the present invention further contains a second crosslinking aid compound other than the compound of Chemical Formula 1, the weight ratio of the compound of Chemical Formula 1 to the second crosslinking aid compound may be 1:0.20 to 9.0. Specifically, it may be 1:0.20 to 6.0, 1:0.20 to 5.0, 1:0.20 to 4.0, 1:0.20 to 3.7, 1:0.25 to 5.0, 1:0.25 to 4.0, 1:0.25 to 3.7, 1:0.25 to 3.5, 1:0.25 to 3.2, 1:0.25 to 3.0, 1:0.3 to 3.7, 1:0.3 to 3.5, 1:0.3 to 3.2, 1:0.3 to 3.0, or 1:0.33 to 3.0.

[0042] When the crosslinking aid composition for an olefin copolymer according to an embodiment of the present invention contains both the compound of Chemical Formula 1 and a second crosslinking aid compound, a higher degree of crosslinking can be achieved compared to the case where only an equivalent amount of the compound of Chemical Formula 1 is contained. When it is applied to the encapsulant composition for an optical element, the encapsulant composition for an optical element can exhibit a high volume resistivity and can satisfy excellent light transmittance and adhesion.

[0043] When both the compound of Chemical Formula 1 and a second crosslinking aid are contained and the ratio of the second crosslinking aid to the compound of Chemical Formula 1 is increased to a certain amount or more, the degree of crosslinking can be increased and the vulcanization characteristics can be improved. When the ratio of the second crosslinking aid to the compound of Chemical Formula 1 is decreased, the degree of decrease in the impregnation rate can be decreased. Therefore, the ratio can be appropriately determined within the above range according to the physical properties to be exhibited. When the ratio of the second crosslinking aid is excessive, it is difficult to appropriately exhibit the effect of improving the impregnation rate by using the compound of Chemical Formula 1. When the ratio of the second crosslinking aid is too small, it may be difficult to appropriately exhibit the additional effect obtained by the mixed use of the second crosslinking aid.

[0044] In the crosslinking aid composition for an olefin copolymer according to an embodiment of the present invention, in order to achieve excellent vulcanization characteristics, degree of crosslinking, and volume resistivity, as well as a shortened impregnation time of the crosslinking agent, both the compound of Chemical Formula 1 and a second crosslinking aid compound are contained, and the compound of Chemical Formula 1 and the second crosslinking aid compound may be contained in a weight ratio of 1:0.20 to 3.7, specifically 1:0.25 to 3.7, 1:0.25 to 3.5, 1:0.25 to 3.2, 1:0.25 to 3.0, 1:0.3 to 3.7, 1:0.3 to 3.5, 1:0.3 to 3.2, 1:0.3 to 3.0, or 1:0.33 to 3.0.

[0045] As the crosslinking agent, various crosslinking agents known in the art can be variously used as long as they are crosslinkable compounds that can initiate radical polymerization or form crosslinking bonds, and one or more selected from the group consisting of organic peroxides, hydroperoxides, and azo compounds may be used.

[0046] Also, in one embodiment of the present invention, the crosslinking agent may specifically be an organic peroxide. The organic peroxide may be an organic peroxide having a one-hour half-life temperature of 120 to 135 °C, for example, 120 to 130 °C, 120 to 125 °C, specifically 121 °C. The "one-hour half-life temperature" means the temperature at which the half-life of the crosslinking agent becomes one hour. Depending on the one-hour half-life temperature, the temperature at which the radical initiation reaction occurs efficiently is different. Therefore, when an organic peroxide having a one-hour half-life temperature within the above-described range is used as the crosslinking agent, the radical initiation reaction, that is, the crosslinking reaction, can be effectively carried out at the lamination process temperature for manufacturing the optoelectronic device.

[0047] Examples of the crosslinking agent include, but are not limited to, one or more selected from the group consisting of dialkyl peroxides such as t-butyl cumyl peroxide, di-t-butyl peroxide, di-cumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexyne; hydroperoxides such as cumene hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethyl-2,5-di(hydroperoxy)hexane, t-butyl hydroperoxide; diacyl peroxides such as bis-3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, benzoyl peroxide, o-methylbenzoyl peroxide, 2,4-dichlorobenzoyl peroxide; peroxy esters such as t-butyl peroxyisobutyrate, t-butyl peroxyacetate, t-butyl peroxy-2-ethylhexyl carbonate (TBEC), t-butyl peroxy-2-ethylhexanoate, t-butyl peroxypivalate, t-butyl peroxy octoate, t-butyl peroxyisopropyl carbonate, t-butyl peroxybenzoate, di-t-butyl peroxyphtalate, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, 2,5-dimethyl-2,5-di(benzoylperoxy)-3-hexyne; and ketone peroxides such as methyl ethyl ketone peroxide, cyclohexanone peroxide, lauryl peroxide, azobisisobutyronitrile, and azobis(2,4-dimethylvaleronitrile).

[0048] The silane coupling agent may be, for example, one or more selected from the group consisting of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane (MEMO), vinyltrimethoxysilane, vinyltriethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, and p-styryltrimethoxysilane.

[0049] The crosslinking agent composition for the olefin copolymer may contain 20 to 80 parts by weight of the crosslinking agent, 5 to 30 parts by weight of the silane coupling agent, and 10 to 60 parts by weight of a crosslinking aid containing the crosslinking aid compound of Chemical Formula 1. The content of each of the components may mean the relative ratio between the weights of the respective components contained in the crosslinking agent composition for the olefin copolymer.

[0050] The crosslinking agent may be contained in the crosslinking agent composition for the olefin copolymer in an amount of 20 to 80 parts by weight, specifically, 20 parts by weight or more, 25 parts by weight or more, 30 parts by weight or more, 35 parts by weight or more, or 40 parts by weight or more to 80 parts by weight or less, 75 parts by weight or less, or 70 parts by weight or less. When the content of the crosslinking agent is too small, the crosslinking reaction hardly occurs when the olefin copolymer is used. When the content of the crosslinking agent is excessive, the volume resistivity of the encapsulant for optical elements produced using the olefin copolymer may decrease. Therefore, when the crosslinking agent is contained in the crosslinking agent composition for the olefin copolymer within the above range, the encapsulant composition for optical elements using it can appropriately cause a crosslinking reaction and be manufactured as an encapsulant for optical elements, and the manufactured encapsulant for optical elements can exhibit a high volume resistivity.

[0051] The silane coupling agent may be contained in the crosslinking agent composition for the olefin copolymer in an amount of 5 to 30 parts by weight. Specifically, it may be contained in an amount of 5 parts by weight or more, 6 parts by weight or more, 7 parts by weight or more, or 8 parts by weight or more to 20 parts by weight or less, 19 parts by weight or less, or 18 parts by weight or less. When the content of the silane coupling agent is too small, when the olefin copolymer is used, the adhesion of the encapsulant composition for optical elements to the substrate, for example, the adhesion of the encapsulant composition for optical elements to a glass substrate is low, and it is difficult to exhibit performance suitable as an encapsulant for optical elements. When the content of the silane coupling agent is excessive, the volume resistivity of the encapsulant for optical elements decreases, which is not preferable. When the silane coupling agent is contained in the above range in the crosslinking agent composition for the olefin copolymer, the encapsulant composition for optical elements using the same exhibits excellent adhesiveness to the substrate of the optical element or the glass substrate on which the optical element is located, effectively prevents the penetration of moisture, etc., and enables the optical element to maintain excellent performance in the long term, and the encapsulant for optical elements can exhibit a high volume resistivity.

[0052] The crosslinking aid containing the crosslinking aid compound of Chemical Formula 1, that is, the crosslinking aid compound of Chemical Formula 1 as the crosslinking aid, or the total amount of the crosslinking aid compound of Chemical Formula 1 and the second crosslinking aid compound may be contained in the crosslinking agent composition for the olefin copolymer in an amount of 10 to 60 parts by weight. Specifically, it may be contained in an amount of 11 parts by weight or more, 12 parts by weight or more, or 13 parts by weight or more to 60 parts by weight or less, 55 parts by weight or less, or 50 parts by weight or less.

[0053] The olefin copolymer to which the crosslinking agent composition for the olefin copolymer is applicable may satisfy, for example, a) a density of 0.85 to 0.90 g / cc and (b) a melt index of 0.1 to 100 g / 10 min.

[0054] Specifically, the (a) density of the olefin copolymer may be 0.850 g / cc or more, 0.855 g / cc or more, 0.860 g / cc or more, 0.865 g / cc or more, or 0.870 g / cc to 0.900 g / cc or less, 0.895 g / cc or less, 0.890 g / cc or less, 0.885 g / cc or less, or 0.880 g / cc or less. When the density of the olefin copolymer is too high, the light transmittance of the encapsulant composition for optical elements using the same and the encapsulant for optical elements manufactured using the same may decrease due to the crystalline phase contained in the olefin copolymer. However, when the olefin copolymer satisfies the above density range, it can exhibit a high light transmittance.

[0055] The (b) melt index of the olefin copolymer may be 0.1 g / 10 min or more, 0.5 g / 10 min or more, 1.0 g / 10 min or more, 1.5 g / 10 min or more, 2.0 g / 10 min or more, 2.5 g / 10 min or more, 3.0 g / 10 min, or 3.5 g / 10 min or more to 100 g / 10 min or less, 95 g / 10 min or less, 90 g / 10 min or less, 85 g / 10 min or less, 80 g / 10 min or less, 75 g / 10 min or less, 70 g / 10 min or less, 60 g / 10 min or less, or 50 g / 10 min or less. When the melt index of the olefin copolymer is out of the above range and is too low or too high, there may be a problem that the moldability of the encapsulant composition for optical elements deteriorates and stable extrusion is difficult. However, when the olefin copolymer satisfies the above melt index range, since the moldability of the encapsulant composition for optical elements is excellent, the encapsulant for optical elements and the encapsulant sheet for optical elements can be extruded stably.

[0056] Specifically, the olefin copolymer to which the crosslinking agent composition for olefin copolymers according to an embodiment of the present invention is applied may be an ethylene / α-olefin copolymer.

[0057] Generally, the density of an ethylene / α-olefin copolymer is affected by factors such as the type and content of monomers used during polymerization, the degree of polymerization, etc. In the case of a copolymer, it is greatly influenced by the content of the comonomer. At this time, the higher the content of the comonomer, the lower-density ethylene / α-olefin copolymer can be produced, and the content at which the comonomer can be introduced into the copolymer depends on the copolymerizability inherent to the catalyst.

[0058] The ethylene / α-olefin copolymer to which the crosslinking agent composition for an olefin copolymer of the present invention is applied may exhibit the above-described low density and excellent processability.

[0059] The ethylene / α-olefin copolymer is produced by copolymerizing ethylene and an α-olefin monomer. At this time, the α-olefin, which means the portion derived from the α-olefin monomer in the copolymer, is an α-olefin having 3 to 20 carbon atoms, specifically, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, 1-hexadecene, or 1-eicosene, etc. Among these, it may be one kind alone or a mixture of two or more kinds. Among them, the α-olefin may be 1-butene, 1-hexene, or 1-octene, specifically, 1-butene, 1-hexene, or a combination thereof.

[0060] Also, the content of the α-olefin in the ethylene / α-olefin copolymer may be appropriately selected within the range that satisfies the above physical property requirements, specifically, more than 0 mol% and 99 mol% or less, or 10 mol% to 50 mol%, but is not limited thereto.

[0061] Also, the olefin copolymer may be an ethylene α-olefin copolymer having a volume resistivity of 1.0×10 15 Ω·cm or more, specifically, 3.0×10 15 Ω·cm or more, 5.0×10 15 Ω·cm, or 7.0×1015 It may be a copolymer having a volume resistivity of 10 17 Ω·cm or more. When the volume resistivity of the olefin copolymer is too low, the volume resistivity after crosslinking of the encapsulant composition for optical elements cannot reach an appropriate level. However, when the volume resistivity of the olefin copolymer satisfies the above value, the encapsulant composition for optical elements can exhibit an excellent volume resistivity after crosslinking. The upper limit of the volume resistivity of the olefin copolymer is not particularly limited. However, considering the volume resistivity usually exhibited by the olefin copolymer and the difficulty in manufacturing an olefin copolymer having a high volume resistivity, 9.9×10 17 Ω·cm or less, 9.0×10 17 Ω·cm or less, or 7.0×10

[0062] [Encapsulant composition for optical elements] The crosslinking agent composition for olefin copolymers of the present invention can be used together with an olefin copolymer to form an encapsulant composition for optical elements. The present invention provides an encapsulant composition for optical elements including an olefin copolymer and the crosslinking agent composition for olefin copolymers.

[0063] The description of the olefin copolymer and the encapsulant composition for optical elements is as described above. The olefin copolymer may be contained in an amount of 80 to 99.5 parts by weight based on 100 parts by weight of the encapsulant composition for optical elements. Specifically, it may be 80 parts by weight or more, 82 parts by weight or more, 85 parts by weight or more, 86 parts by weight or more, 87 parts by weight or more, or 88 parts by weight or more to 99.5 parts by weight or less, 99 parts by weight or less, or 98.5 parts by weight or less. When the content of the olefin copolymer contained in the encapsulant composition for optical elements is too small, it is difficult to appropriately exhibit mechanical properties such as tear resistance and tear strength of the encapsulant for optical elements. Therefore, when the olefin copolymer is contained in the entire encapsulant composition for optical elements within the above range, it can exhibit mechanical properties suitable for an encapsulant for optical elements.

[0064] The crosslinking agent composition for an olefin copolymer according to an embodiment of the present invention may be used in an amount of 0.5 to 20 parts by weight based on 100 parts by weight of the olefin copolymer. Specifically, the crosslinking agent composition for the olefin copolymer may be used in an amount of 0.5 parts by weight or more, 0.7 parts by weight or more, 0.8 parts by weight or more, 1 part by weight or more, 1.1 parts by weight or more, 1.2 parts by weight or more, 1.3 parts by weight or more, 1.4 parts by weight or more, or 1.5 parts by weight or more to 20 parts by weight or less, 18 parts by weight or less, 15 parts by weight or less, 10 parts by weight or less, 8 parts by weight or less, 6 parts by weight or less, 5 parts by weight or less, or 3 parts by weight or less based on 100 parts by weight of the olefin copolymer. When the amount of the crosslinking agent composition used with respect to the olefin copolymer is too small, the crosslinking reaction hardly occurs. When the amount of the crosslinking agent composition used is excessive, the volume resistivity of the encapsulant for an optical element may decrease. When the crosslinking agent composition is used in the above ratio with respect to the olefin copolymer, the encapsulant composition for an optical element using the same can appropriately cause a crosslinking reaction and can be manufactured as an encapsulant for an optical element, and the manufactured encapsulant for an optical element can exhibit a high volume resistivity.

[0065] In the encapsulant composition for an optical element according to an embodiment of the present invention, the crosslinking auxiliary compound of Chemical Formula 1 may be contained in an amount of 0.1 to 9 parts by weight with respect to 100 parts by weight of the olefin copolymer. Specifically, the crosslinking auxiliary compound of Chemical Formula 1 may be contained in an amount of 0.1 part by weight or more, 0.2 part by weight or more, 0.3 part by weight or more, or 0.4 part by weight or more to 9 parts by weight or less, 8 parts by weight or less, 7 parts by weight or less, 6 parts by weight or less, 5 parts by weight or less, 4 parts by weight or less, 3 parts by weight or less, or 2 parts by weight or less with respect to 100 parts by weight of the olefin copolymer. When both the crosslinking auxiliary compound of Chemical Formula 1 and the second crosslinking auxiliary compound are used as crosslinking auxiliaries, the total amount thereof can satisfy the above range. When the amount of the crosslinking auxiliary used with respect to the olefin copolymer is too small, the crosslinking reaction hardly occurs, and when the amount of the crosslinking auxiliary used is excessive, the volume resistivity of the encapsulant for an optical element may decrease. When the crosslinking auxiliary is contained in the above ratio with respect to the olefin copolymer, the encapsulant composition for an optical element can appropriately cause a crosslinking reaction to form an encapsulant for an optical element, and the formed encapsulant for an optical element can exhibit a high volume resistivity.

[0066] In addition to the above components, the encapsulant composition for an optical element may further appropriately contain various additives known in the art according to the application to which the resin component is applied. Examples of the additive include one or more additives selected from a light stabilizer, a UV absorber, a heat stabilizer, and the like.

[0067] The light stabilizer can play a role of capturing active species at the start of photo-degradation of the resin and preventing photo-oxidation according to the application to which the composition is applied. The type of the light stabilizer that can be used is not particularly limited, and for example, known compounds such as hindered amine-based compounds or hindered piperidine-based compounds may be used.

[0068] The UV absorber can absorb ultraviolet rays from sunlight or the like according to the use of the composition, convert them into harmless thermal energy within the molecule, and prevent the active species that initiate photo-degradation in the resin composition from being excited. The specific types of UV absorbers that can be used are not particularly limited. For example, one or a mixture of two or more of benzophenone-based, benzotriazole-based, acrylonitrile-based, metal complex-based, hindered amine-based, inorganic UV absorbers such as ultrafine titanium oxide or ultrafine zinc oxide may be used.

[0069] Examples of the heat stabilizer include phosphorus-based heat stabilizers such as tris(2,4-di-tert-butylphenyl) phosphite, bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl] ethyl ester phosphite, tetrakis(2,4-di-tert-butylphenyl)[1,1-biphenyl]-4,4'-diyl bisphosphonate, and bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite; and lactone-based heat stabilizers such as the reaction product of 8-hydroxy-5,7-di-tert-butyl-furan-2-one and o-xylene. One or two or more of these may be used.

[0070] The content of the light stabilizer, UV absorber, and / or heat stabilizer is not particularly limited. That is, the content of the additive may be appropriately selected in consideration of the use of the resin composition, the shape and density of the additive, etc., and is usually appropriately adjusted within the range of 0.01 to 5 parts by weight based on 100 parts by weight of the total solid content of the encapsulant composition for optical elements.

[0071] In addition, the encapsulant composition for optical elements can be molded by methods such as injection and extrusion and utilized as various molded products. Specifically, it can be used as an encapsulant for encapsulating elements in various optoelectronic devices, such as solar cells. For example, it can also be used as an industrial material applied to processes such as the temperature-rising lamination process, but is not limited to these uses.

[0072] Furthermore, the present invention provides a sealing material film for an optical element manufactured using the above-described sealing material composition for an optical element. The sealing material film for an optical element according to an embodiment of the present invention may include a structure derived from an olefin copolymer and a crosslinking aid compound represented by the following Chemical Formula 1.

[0073]

Chemical formula

[0074] The description of the olefin copolymer and the crosslinking aid compound of Chemical Formula 1 is as described above. In addition, the sealing material film for an optical element according to another embodiment of the present invention may include structures respectively derived from the crosslinking aid compound of Chemical Formula 1 and the second crosslinking aid compound.

[0075] The description of the second crosslinking aid compound and the description of the case where both the crosslinking aid compound of Chemical Formula 1 and the second crosslinking aid compound are used as crosslinking aids are as described above. Furthermore, the present invention provides an optoelectronic device including the above-described sealing material film for an optical element.

[0076] Example Hereinafter, the present invention will be described in more detail with reference to examples. However, the following examples are for illustrative purposes only, and the scope of the present invention is not limited thereto.

[0077] Example 1 3-(Triallylsilyl)propyl acrylate [TPA, manufactured by Tokyo Chemical Industry co., ltd.] and triallyl isocyanurate (TAIC, manufactured by Sigma-Aldrich) were mixed in amounts of 25 parts by weight and 75 parts by weight, respectively, and prepared as a crosslinking aid.

[0078] LUCENE of LG Chemie, an ethylene / 1-butene copolymer TM 500 g of LF675 was dried overnight using a convection oven at 40 °C. The said LUCENE TM The density measured according to ASTM D1505 of the said LF675 was 0.877 g / cm 3 and the melt index (190 °C, 2.16 Kg) measured according to ASTM D1238 was 14.0 g / 10 min. The bowl temperature of the Haake Modular Torque Viscometer was set at 40 °C. After charging the ethylene / α-olefin copolymer into the bowl, a crosslinking agent composition [1.00 phr (parts per hundred rubber) of t-butyl 1-(2-ethylhexyl) monoperoxycarbonate (TBEC, manufactured by Sigma-Aldrich) as the crosslinking agent, 0.50 phr of a mixture of TPA and TAIC (weight ratio 50:50) prepared above as the crosslinking aid, 0.20 phr of methacryloxypropyltrimethoxysilane (MEMO, manufactured by Shin-Etsu) as the silane coupling agent] was charged using an electric pipette. While stirring at 40 °C and 40 rpm, the change in the torque value according to time was observed, and when the torque value increased rapidly, the impregnation was terminated, and the impregnation completion time of the crosslinking agent composition was measured.

[0079] Thereafter, the impregnated sample was press-molded to an average thickness of 0.5 mm at a low temperature (under the condition that the extruder barrel temperature was 90 - 100 °C) such that high-temperature crosslinking was not performed, and a sheet-shaped sealing material film was produced.

[0080] Example 2 A crosslinking aid was prepared in the same manner as in Example 1 except that the mixing ratio of 3-(triallylsilyl)propyl acrylate (TPA) and triallyl isocyanurate (TAIC) as the crosslinking aids was changed to 50 parts by weight and 0 parts by weight, respectively, and thereafter, a sealing material film was produced.

[0081] Example 3 As a crosslinking aid, 3-(triallylsilyl)propyl acrylate (TPA) and triallyl isocyanurate (TAIC) were used in amounts of 75 parts by weight and 25 parts by weight, respectively, except that the mixing ratio was changed. A crosslinking aid was prepared in the same manner as in Example 1, and then a sealing material film was manufactured.

[0082] Example 4 As a crosslinking aid, only 3-(triallylsilyl)propyl acrylate (TPA) was used. Except that the input amount was changed from 0.50 phr to 0.25 phr, a crosslinking aid was prepared in the same manner as in Example 1, and then a sealing material film was manufactured.

[0083] Example 5 As a crosslinking aid, only 3-(triallylsilyl)propyl acrylate (TPA) was used. A crosslinking aid was prepared in the same manner as in Example 1, and then a sealing material film was manufactured.

[0084] Example 6 As a crosslinking aid, 3-(triallylsilyl)propyl acrylate (TPA) and triallyl isocyanurate (TAIC) were used in amounts of 10 parts by weight and 90 parts by weight, respectively, except that the mixing ratio was changed. A crosslinking aid was prepared in the same manner as in Example 1, and then a sealing material film was manufactured.

[0085] Example 7 As a crosslinking aid, 3-(triallylsilyl)propyl acrylate (TPA) and triallyl isocyanurate (TAIC) were used in amounts of 20 parts by weight and 80 parts by weight, respectively, except that the mixing ratio was changed. A crosslinking aid was prepared in the same manner as in Example 1, and then a sealing material film was manufactured.

[0086] Example 8 As a crosslinking aid, except that the mixing ratio of 3-(triallylsilyl)propyl acrylate (TPA) and triallyl isocyanurate (TAIC) was changed to 80 parts by weight and 20 parts by weight, respectively, the crosslinking aid was prepared in the same manner as in Example 1 above, and then a sealing material film was produced.

[0087] Comparative Example 1 Except that only triallyl isocyanurate (TAIC) was used as the crosslinking aid, the crosslinking aid was prepared in the same manner as in Example 1 above, and then a sealing material film was produced. Table 1 below shows the crosslinking agent compositions used in Examples 1 to 8 and Comparative Example 1.

[0088]

Table 1

[0089] Experimental Example A 0.5 mm thick sealing material film (10 cm × 10 cm) manufactured above was placed between two release films (thickness: about 100 μm), and laminated and crosslinked at a process temperature of 150 °C for a process time of 20 minutes (5 minutes of vacuum / 1 minute of pressurization / 14 minutes of pressure maintenance) using a vacuum laminator.

[0090] (1) Impregnation rate The impregnation completion times of the crosslinking agents measured in Examples 1 to 8 and Comparative Example 1 above are shown in Table 2 below.

[0091] (2) Volume resistivity Measurement was carried out by applying a voltage of 1,000 V for 600 seconds using an Agilent 4339B High-Resistance meter (Agilent Technologies) under the conditions of a temperature of 23 ± 1 °C and a humidity of 50 ± 3%.

[0092] (3) Vulcanization characteristics The vulcanization properties were measured using an Alpha Technologies Premier MDR in accordance with ASTM D5289. The test was performed at 150°C for 20 minutes, and a torque curve was obtained as a function of time. In this case, 150°C corresponds to the lamination temperature, and 20 minutes corresponds to the lamination time. In addition, the vulcanization properties of the samples were compared relative to each other using the difference between the maximum torque (MH) and the minimum torque (ML) applied by the MDR during that time.

[0093] (4) Degree of crosslinking The crosslinked sheet was cut into 3 × 3 mm pieces using scissors. 2 Cut to size: 7×14cm 2 The sides and bottom of a 200 mesh wire net were sealed with staples. The sheet was placed in the wire net, and the weight of the sheet was measured. The amount of the sheet was set to 0.49 to 0.51 g. After the sheet was placed, the top of the wire net was sealed with staples, and the weight of the entire sample was measured. A solution of 10 g of BHT (dibutylhydroxytoluene) dissolved in 1,000 g of xylene was poured into a 2 L cylindrical reactor, and 3 to 4 of the samples were placed in it. The reactor was heated, and reflux was terminated when 5 hours had elapsed at the point when the solution began to boil. The sample in the reactor was taken out with a metal strainer and washed with xylene. It was vacuum dried overnight at 100°C. The weight of the dried sample was measured, and the degree of crosslinking was calculated. The degree of crosslinking can be determined as the average value of 3 to 4 samples refluxed with xylene. Crosslinking degree (%) = [(weight of sheet after reflux) / (weight of sheet before reflux)] × 100

[0094] [Table 2]

[0095] As can be confirmed from Table 2 above, when using the crosslinking agent compositions containing the crosslinking aid compounds of Chemical Formula 1 in Examples 1 to 8, the impregnation completion time of the crosslinking agent could be shortened as compared with the case of using triallyl isocyanurate in Comparative Example 1 as the crosslinking aid. Further, when containing a certain amount or more of the crosslinking aid compound of Chemical Formula 1 together with triallyl isocyanurate as in Examples 1 to 3 and 6 to 8, the impregnation completion time of the crosslinking agent could be shortened, and high crosslinking degree and high volume resistivity could be achieved.

Claims

1. A crosslinking agent, a silane coupling agent, and a crosslinking aid compound represented by the following Chemical Formula 1, the crosslinking agent composition for an olefin copolymer containing the same. 【Chemical 1】 In the Chemical Formula 1, R １ to R ４ each independently represents an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 20 carbon atoms, m is an integer of 1 to 20.

2. Said R １ to R ４ are each independently an alkenyl group having 2 to 8 carbon atoms, The crosslinking agent composition for an olefin copolymer according to Claim 1, wherein m is an integer of 1 to 12.

3. The above R １ to R ４ is, independently of each other, an alkenyl having 2 to 8 carbon atoms and having a double bond at the terminal, the crosslinking agent composition for an olefin copolymer according to claim 1.

4. The crosslinking agent composition for an olefin copolymer according to Claim 1, wherein the crosslinking aid compound of the Chemical Formula 1 is 3-(triallylsilyl)propyl acrylate.

5. The crosslinking agent composition for an olefin copolymer according to Claim 1, further comprising a second crosslinking aid compound other than the crosslinking aid compound of the Chemical Formula 1.

6. The crosslinking agent composition for an olefin copolymer according to Claim 5, wherein the weight ratio of the crosslinking aid compound of the Chemical Formula 1 to the second crosslinking aid compound is 1:0.2 to 1:

9.

7. The crosslinking agent composition for an olefin copolymer according to Claim 5, wherein the second crosslinking aid compound contains one or more selected from the group consisting of triallyl isocyanurate, triallyl cyanurate, diallyl phthalate, diallyl fumarate, diallyl maleate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, and trimethylolpropane trimethacrylate.

8. The crosslinking agent composition for an olefin copolymer according to Claim 1, wherein the crosslinking agent is one or more selected from the group consisting of organic peroxides, hydroperoxides, and azo compounds.

9. The crosslinking agent is one or more selected from the group consisting of t-butylcumyl peroxide, di-t-butyl peroxide, di-cumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexyne, cumene hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethyl-2,5-di(hydroperoxy)hexane, t-butyl hydroperoxide, bis-3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, benzoyl peroxide, o-methylbenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, t-butyl peroxyisobutyrate, t-butyl peroxyacetate, t-butyl peroxy-2-ethylhexyl carbonate (TBEC), t-butyl peroxy-2-ethylhexanoate, t-butyl peroxypivalate, t-butyl peroxy octoate, t-butyl peroxyisopropyl carbonate, t-butyl peroxybenzoate, di-t-butyl peroxyphtalate, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, 2,5-dimethyl-2,5-di(benzoylperoxy)-3-hexyne, methyl ethyl ketone peroxide, cyclohexanone peroxide, azobisisobutyronitrile, and azobis(2,4-dimethylvaleronitrile), the crosslinking agent composition for an olefin copolymer according to claim 1.

10. The silane coupling agent is one or more selected from the group consisting of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, and p-styryltrimethoxysilane, the crosslinking agent composition for an olefin copolymer according to claim 1.

11. an olefin copolymer, and A sealing material composition for an optical element, comprising the crosslinking agent composition for an olefin copolymer according to claim 1.

12. The sealing material composition for an optical element according to claim 11, wherein the olefin copolymer is an ethylene α-olefin copolymer.

13. An olefin copolymer and a structure derived from the compound of the following Chemical Formula 1, A sealing material film for an optical element. 【Chemical 2】 In the Chemical Formula 1, R １ to R ４ are each independently an alkyl having 1 to 20 carbon atoms or an alkenyl having 2 to 20 carbon atoms, m is an integer of 1 to 20.

14. An optoelectronic device, comprising an optical element and the sealing material film for an optical element according to claim 13.

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