[One]Cross-Citation with Related Applications
[2]This application claims the benefit of priority based on the Korean Patent Application 2019-0120125 filed on September 27, 2019, and all contents disclosed in the documents of the Korean patent applications are incorporated as a part of this specification.
[3]
[4]
technical field
[5]
The present invention relates to an ethylene/alpha-olefin copolymer that can be usefully used as an insulating material by improving the volume resistance by shortening the stress relaxation time, a composition for an encapsulant film using the same, and an encapsulant film comprising the same.
[6]
background
[7]
While global environmental problems and energy problems are getting more and more serious, solar cells are attracting attention as a means of generating energy that does not cause environmental pollution and depletion. When a solar cell is used outdoors, such as on the roof of a building, it is generally used in the form of a solar cell module. In order to obtain a crystalline solar cell module at the time of manufacturing a solar cell module, a protective sheet for a solar cell module (front side protection member) / solar cell encapsulant / crystalline solar cell element / solar cell encapsulant / protective sheet for solar cell module (back side) protection members) in the order of In addition, at the time of manufacturing a thin-film solar cell module, it laminates|stacks in order of the thin film type solar cell element/solar cell sealing material/protective sheet for solar cell modules (back surface side protection member). As the solar cell encapsulant, an ethylene/vinyl acetate copolymer or an ethylene/alpha-olefin copolymer, which is generally excellent in transparency, flexibility, and adhesion, is used.
[8]
On the other hand, although the solar cell module is generally used for a long period of time outside, problems such as performance degradation due to various external stimuli are continuously observed. In particular, it is urgent to solve the PID (Potential Induced Degradation) phenomenon found in the form of a high-output power plant.
[9]
In a large-capacity power generation system that obtains a high voltage by connecting a plurality of solar cell modules, the volume resistance of the encapsulant decreases as the temperature and humidity of the installed place increase, and a potential difference occurs between the solar cell and the frame. As a result, toward the end of the array in which several solar cell modules are connected in series, the potential difference between the solar cell and the frame increases. A phenomenon in which leakage current is generated in the presence of such a potential difference and the power generation efficiency is rapidly reduced is referred to as a PID phenomenon.
[10]
Under the above background, it is required to develop an ethylene/alpha-olefin copolymer capable of continuously preventing the PID phenomenon by improving the volume resistance without reducing the light transmittance.
[11]
[12]
[Prior art literature]
[13]
[Patent Literature]
[14]
Japanese Patent Application Laid-Open No. 2015-211189
[15]
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[16]
An object of the present invention is to provide an ethylene/alpha-olefin copolymer having a high volume resistance due to a shortened stress relaxation time.
[17]
Another object of the present invention is to provide a composition for an encapsulant film comprising the ethylene/alpha-olefin copolymer.
[18]
In addition, it is an object of the present invention to provide an encapsulant film comprising the composition for the encapsulant film.
[19]
Another object of the present invention is to provide a solar cell module including the encapsulant film.
[20]
means of solving the problem
[21]
In order to solve the above problems, the present invention provides an ethylene/alpha-olefin copolymer satisfying the following conditions (a) to (c).
[22]
(a) 190 ° C., the stress relaxation time (Characteristic Relaxation Time, λ) at a shear rate of 0.1 to 500 rad/s is less than 10.0 ms (millisecond);
[23]
(b) a weight average molecular weight of 40,000 to 150,000 g/mol; and
[24]
(c) the molecular weight distribution is 1.5 to 2.5.
[25]
[26]
In addition, the present invention provides a composition for an encapsulant film comprising the ethylene/alpha-olefin copolymer.
[27]
In addition, the present invention provides an encapsulant film comprising the composition for the encapsulant film.
[28]
In addition, the present invention provides a solar cell module including the encapsulant film.
[29]
Effects of the Invention
[30]
The ethylene/alpha-olefin copolymer of the present invention is an ethylene/alpha-olefin copolymer having a high weight average molecular weight and a narrow molecular weight distribution, and at the same time having a shortened stress relaxation time. Since the ethylene/alpha-olefin copolymer has high volume resistance and excellent insulation properties, it can be used for various purposes in the battery and electronics industry.
[31]
Modes for carrying out the invention
[32]
Hereinafter, the present invention will be described in more detail to help the understanding of the present invention.
[33]
The terms or words used in the description and claims of the present invention should not be construed as being limited to their ordinary or dictionary meanings, and the inventor appropriately defines the concept of the term in order to best describe his invention. Based on the principle that it can be done, it should be interpreted as meaning and concept consistent with the technical idea of ​​the present invention.
[34]
[35]
Ethylene/alpha-olefin copolymer
[36]
The ethylene/alpha-olefin copolymer of the present invention is characterized in that the following conditions (a) to (c) are satisfied.
[37]
(a) 190 ° C., the stress relaxation time (Characteristic Relaxation Time, λ) at a shear rate of 0.1 to 500 rad/s is less than 10.0 ms (millisecond);
[38]
(b) a weight average molecular weight of 40,000 to 150,000 g/mol; and
[39]
(c) the molecular weight distribution is 1.5 to 2.5.
[40]
[41]
As described below, the ethylene/alpha-olefin copolymer of the present invention is subjected to a post-treatment in which a polymerization product of ethylene and an alpha-olefin monomer is dissolved in an organic solvent and a step is continuously performed to form a precipitate by mixing with an alcohol. manufactured.
[42]
In the dissolution step and the precipitate formation step, the ethylene/alpha-olefin copolymer is dissolved in an organic solvent capable of completely dissolving it, and then slowly added dropwise to alcohol to obtain a precipitate in a state in which the branched structure of low molecular weight is removed. Through the post-treatment, the stress relaxation time of the ethylene/alpha-olefin copolymer of the present invention is shortened to less than a specific value, and at the same time, it has a high molecular weight and a narrow molecular weight distribution.
[43]
[44]
The ethylene / alpha-olefin copolymer of the present invention (a) 190 ° C., the stress relaxation time (Characteristic Relaxation Time, λ) at a shear rate of 0.1 to 500 rad / s It is characterized in that less than 10.0 ms (millisecond). The stress relaxation time may be less than 10.0 ms, specifically less than 9.5 ms, less than 9.3 ms, or more than 1.0 ms.
[45]
The stress relaxation time means a time for which the stress inside the polymer returns to an equilibrium state after a certain strain is applied to the polymer. The stress relaxation time is related to the entanglement structure of the polymer. When the polymer has long-chain branches, the entanglement of the chains increases, which causes the stress relaxation time to become longer. That is, the reduction in the stress relaxation time of the polymer means that the degree of entanglement of the chains is lowered, and it is interpreted that some branched structures in the polymer are removed or the branched structures are reduced due to the transformation into a linear structure.
[46]
As ethylene and alpha-olefin monomers are polymerized, both a low molecular weight region and a high molecular weight region are generated in the copolymer. It is produced when premature termination occurs due to elimination. Therefore, the low molecular weight region has a structure with a low molecular weight and a high degree of branching.
[47]
Since the branched structure increases the free volume of the polymer, inhibits crystal formation and causes a decrease in volume resistance, it is recommended to remove a low molecular weight and high branching region in the copolymer to improve the volume resistance. It is important.
[48]
In the present invention, by dissolving the polymerization product of ethylene and alpha-olefin monomer and precipitating it in alcohol, which is a poor solvent, the high molecular weight region in the copolymer is precipitated in alcohol and the low molecular weight region is dissolved in alcohol to separate. That is, the ethylene/alpha-olefin copolymer of the present invention is obtained by obtaining a high molecular weight fraction precipitated in alcohol as a final product. As described above, it contains a small amount of branched structure, and the free volume of the polymer is small, so that the movement of electrons or ions is restricted, and thus the volume resistance can be excellent.
[49]
[50]
The ethylene/alpha-olefin copolymer of the present invention is characterized in that (b) the weight average molecular weight is 40,000 to 150,000 g/mol, and (c) the molecular weight distribution is 1.5 to 2.5.
[51]
In addition, the weight average molecular weight is 40,000 to 150,000 g / mol, specifically 40,000 g / mol or more, 41,000 g / mol or more, 42,000 g / mol or more, 43,000 g / mol or more, 44,000 g / mol or more, and may be 150,000 g/mol or less, 130,000 g/mol or less, and 100,000 g/mol or less.
[52]
In addition, the molecular weight distribution (MWD) may be 1.5 to 2.5, and specifically, 1.50 or more, 1.80 or more, 2.50 or less, 2.40 or less, 2.30 or less, and 2.25 or less.
[53]
The weight average molecular weight (Mw) and the number average molecular weight (Mn) are polystyrene equivalent molecular weights analyzed by gel permeation chromatography (GPC), and the molecular weight distribution can be calculated from a ratio of Mw/Mn.
[54]
In general, when two or more kinds of monomers are polymerized, for example, when a copolymer is prepared by polymerizing ethylene and an alpha-olefin monomer, the termination rate varies depending on the reaction temperature gradient inside the reactor, and side reactions such as beta-hydrogen removal occur. will do As a result, it is difficult to control that a branched structure is generated in the polymer, a low molecular weight chain is generated and the molecular weight distribution is widened, and the stress relaxation time of the polymer is also prolonged. This reduced the impact strength and mechanical properties of the copolymer, and acted as a problem inducing a blocking phenomenon.
[55]
On the other hand, the copolymer of the present invention has a high molecular weight and narrow molecular weight distribution by removing the low molecular weight portion of the branched structure through the process of dissolving in an organic solvent and precipitating it in alcohol as described above, and the stress relaxation time is also shortened. This will appear at the same time.
[56]
On the other hand, the copolymer of the present invention is characterized in that the stress relaxation time is short, the weight average molecular weight is high and the molecular weight distribution is narrow, and through this, excellent volume resistance can be realized.
[57]
For example, even if the molecular weight distribution is narrow, if the copolymer contains a large number of branched structures, the stress relaxation time of the copolymer becomes longer. becomes this In addition, if the molecular weight distribution is wide even for a copolymer having a high linearity and a short stress relaxation time, it inevitably contains a large number of low molecular weight regions, and the volume resistance is lowered due to high chargeability in the low molecular weight region.
[58]
[59]
In the present invention, the ethylene/alpha-olefin copolymer may have a density of 0.850 to 0.910 g/cc measured according to ASTM D-792. Specifically, the density may be 0.850 g/cc or more, 0.855 g/cc or more, 0.860 g/cc or more, or 0.865 or more, and 0.910 g/cc or less, 0.900 g/cc or less, 0.890 g/cc or less.
[60]
In the present invention, the ethylene/alpha-olefin copolymer may have a melt index (Melt Index, MI 2.16 , 190°C, 2.16 kg load condition) of 0.1 to 50 g/10min. Specifically, 0.1 g/10min or more, 1 g/10min or more, 1.5 g/10min or more. 2.0 g/10min or more, 50.0 g/10min or less, 40.0 g/10min or less, 35.0 g/10min or less, 30.0 g/10min or less.
[61]
[62]
In the ethylene/alpha-olefin copolymer, the alpha-olefin is derived from an alpha-olefin monomer that is a comonomer, and may be an alpha-olefin monomer having 4 to 20 carbon atoms. Specific examples include propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dodecene, 1-tetra decene, 1-hexadecene, or 1-eicosene, and the like, and any one of them or a mixture of two or more thereof may be used.
[63]
Among them, the alpha-olefin monomer may be 1-butene, 1-hexene, or 1-octene, and most preferably 1-butene.
[64]
In addition, in the ethylene/alpha-olefin copolymer, the content of the alpha-olefin may be appropriately selected within a range that satisfies the above-mentioned physical property requirements, specifically, more than 0 mol%, 99 mol% or less, or It may be 10 to 50 mol%, but is not limited thereto.
[65]
[66]
Method for preparing ethylene/alpha-olefin copolymer
[67]
The method for producing an ethylene/alpha-olefin copolymer of the present invention comprises the steps of (S1) preparing a polymerization product of ethylene and an alpha-olefin monomer; (S2) dissolving the polymerization product in an organic solvent; and (S3) mixing with an alcohol having 2 to 5 carbon atoms to form a precipitate.
[68]
[69]
Step (S1)
[70]
The step (S1) is a step of preparing a polymerization product of ethylene and an alpha-olefin monomer.
[71]
The polymerization product is a composition in which the ethylene/alpha-olefin copolymer is not separately separated or purified after polymerization of ethylene and alpha-olefin monomers, or is a solid phase by separating only the ethylene/alpha-olefin copolymer after polymerization. It can be used in the meaning of including all obtained by.
[72]
When the polymerization product is a composition in which the ethylene/alpha-olefin copolymer is not separately separated or purified after polymerization of ethylene and alpha-olefin monomers, in addition to the ethylene/alpha-olefin copolymer prepared by the polymerization reaction , unreacted ethylene, unreacted alpha-olefin monomers, catalysts used for polymerization, and the like. In addition, when the polymerization of ethylene and the alpha-olefin monomer is solution polymerization, the polymerization product may include all of the above-mentioned materials and also include a hydrocarbon solvent used for polymerization. In this case, the ethylene/alpha-olefin copolymer may be partially or entirely swollen in the polymerization product, and the remainder may be present in a dispersed state in a hydrocarbon solvent.
[73]
In addition, when the polymerization product is a solid phase obtained by separating only the ethylene/alpha-olefin copolymer after polymerization, in order to prepare the polymerization product, directly polymerize ethylene and alpha-olefin monomers and then remove the solvent, unreacted reactants, etc. All methods such as preparing a commercially available solid ethylene/alpha-olefin copolymer can be used.
[74]
[75]
There is no limitation on the method used for the polymerization of the ethylene and alpha-olefin monomers. For example, by using a catalyst composition comprising a known transition metal compound and a cocatalyst, the polymerization reaction can be carried out through conventional reaction conditions and methods.
[76]
For example, slurry polymerization in which polymerization is performed by supplying a gas or liquid monomer in the presence of an organic solvent, bulk polymerization in which polymerization is performed in the presence of a liquid monomer, gas phase polymerization in which polymerization is performed in the presence of a gaseous monomer, etc. can be mentioned. , a polymerization method such as continuous or batch polymerization is not limited, and polymerization conditions such as polymerization temperature and pressure may also be appropriately adjusted by a person skilled in the art.
[77]
[78]
Step (S2)
[79]
The step (S2) is a step of dissolving the polymerization product in an organic solvent, and is a step for dissolving the ethylene/alpha-olefin copolymer present in a swollen or solid state in the polymerization product. In order to maximize the effect of removing the low-molecular-weight fraction through alcohol precipitation in step (S3), the step of dissolving the ethylene/alpha-olefin copolymer that is not dissolved in the solution and is swollen or in a solid state to release the chain is first because it has to be done.
[80]
In the aspect for preferably realizing the above object, as the organic solvent, a compound having 7 to 16 carbon atoms may be preferably used. When the carbon number of the organic solvent is 6 or less, the solubility in the ethylene/alpha-olefin copolymer may not be sufficient, and the boiling point of the organic solvent is lower than that of the ethylene/alpha-olefin copolymer, so step (S2) is performed Depending on the temperature at which the organic solvent is dried, a problem may occur. In addition, when the carbon number of the organic solvent is 17 or more, the organic solvent is present in a solid state at room temperature, so that it is difficult to dissolve the ethylene/alpha-olefin copolymer.
[81]
The organic solvent may be at least one selected from the group consisting of heptane, octane, isooctane, toluene, xylene, and cumene, preferably heptane, but is not limited thereto.
[82]
[83]
Step (S3)
[84]
The step (S3) is a step of forming a precipitate by mixing with an alcohol having 2 to 5 carbon atoms, in order to remove the low molecular weight fraction in the dissolved ethylene/alpha-olefin copolymer and to obtain a high molecular weight fraction as a precipitate.
[85]
In the high molecular weight fraction precipitated in the alcohol, compared with the polymerization product prior to performing steps (S2) and (S3), the low molecular weight and branched chain portions in the ethylene/alpha-olefin copolymer were removed. . Therefore, the copolymer obtained therefrom contains a small amount of free volume and the volume resistivity is improved.
[86]
[87]
The alcohol having 2 to 5 carbon atoms is ethanol, propan-1-ol, propan-2-ol, butan-1-ol. ), butan-2-ol (butan-2-ol), 2-methylpropan-2-ol (2-methylpropan-2-ol), pentan-1-ol (pentan-1-ol), pentan-2- ol (pentan-2-ol), pentan-3-ol (pentan-3-ol), 2-methylbutan-2-ol (2-methylbutan-2-ol) and 3-methylbutan-2-ol (3 -methylbutan-2-ol) may be one or more selected from the group consisting of, but is not limited thereto. Preferably, the alcohol having 2 to 5 carbon atoms may be propan-2-ol or butan-2-ol, more preferably propan-2-ol (isopropyl alcohol).
[88]
Methanol having 1 carbon number is a non-solvent, so the removal effect of the low molecular weight portion is insignificant, and the alcohol having 6 or more carbon atoms has excessive solubility with the copolymer, so it dissolves even the high molecular weight portion. A problem may arise in that the yield of obtaining only the high molecular weight portion of the olefin copolymer becomes low.
[89]
[90]
In the present invention, the steps (S2) and (S3) may be alternately repeated 2 to 5 times, respectively. Preferably, steps (S2) and (S3) are alternately repeated 4 or 5 times, respectively. can be done Here, performing two repetitions alternately means sequentially performing steps (S2), steps (S3), steps (S2), and steps (S3), and alternately performing four repetitions means steps (S2), steps ( S3), step (S2), step (S3), step (S2), step (S3), step (S2), step (S3) are sequentially performed.
[91]
As the number of repetitions of steps (S2) and (S3) increases, the low molecular weight fraction that has not been removed can be dissolved and removed. . In consideration of the cleaning effect and economic feasibility, it is preferable to wash the number of times 4 or 5 times.
[92]
[93]
In addition, the manufacturing method, filtering the result of step (S3), washing and drying the filtrate to obtain an ethylene / alpha-olefin copolymer; may further include.
[94]
[95]
Composition for encapsulant film and encapsulant film
[96]
The ethylene/alpha-olefin copolymer of the present invention may be prepared as a resin composition by including an additional material, and the resin composition may be molded by injection, extrusion, or the like, and used as various molded articles. Specifically, it may be used as an encapsulant for encapsulating a device in various optoelectronic devices, and may be used as an industrial material applied to, for example, an elevated temperature lamination process, but the use is not limited thereto.
[97]
Specifically, the ethylene/alpha-olefin copolymer of the present invention may be processed into a composition for an encapsulant film, for example, a silane-modified resin composition or an amino silane-modified resin composition may be prepared.
[98]
[99]
Specifically, the composition for the encapsulant film may include a known crosslinking agent, a crosslinking aid, a silane coupling agent, etc. in addition to the above-described ethylene/alpha-olefin copolymer.
[100]
The crosslinking agent is a radical initiator in the manufacturing step of the silane-modified resin composition, and may serve to initiate a reaction in which the unsaturated silane compound is grafted to the resin composition. In addition, by forming a crosslink between the silane-modified resin composition or between the silane-modified resin composition and the non-modified resin composition in the lamination step during the manufacture of an optoelectronic device, the heat resistance durability of the final product, such as an encapsulant film, can be improved. have.
[101]
If the crosslinking agent is a crosslinking compound capable of initiating radical polymerization of a vinyl group or forming a crosslinking bond, various crosslinking agents known in the art can be variously used, for example, organic peroxides, hydroperoxides and azo compounds. One or two or more selected from the group consisting of may be used.
[102]
Specifically, t-bufilcumyl peroxide, di-t-butyl peroxide, di-cumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5-dimethyl dialkyl peroxides such as -2,5-di(t-butylperoxy)-3-hexyne; hydroperoxides such as cumene hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethyl-2,5-di(hydroperoxy)hexane and t-butyl hydroperoxide; diacyl peroxides such as bis-3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, benzoyl peroxide, o-methylbenzoyl peroxide and 2,4-dichlorobenzoyl peroxide; t-butylperoxyisobutylate, t-butylperoxyacetate, t-butylperoxy-2-ethylhexylcarbonate (TBEC), t-butylperoxy-2-ethylhexanoate, t-butylperoxypiva Late, t-butylperoxyoctoate, t-butylperoxyisopropyl carbonate, t-butylperoxybenzoate, di-t-butylperoxyphthalate, 2,5-dimethyl-2,5-di(benzoylperate) peroxy esters such as oxy)hexane and 2,5-dimethyl-2,5-di(benzoylperoxy)-3-hexyne; and ketone peroxides such as methyl ethyl ketone peroxide, cyclohexanone peroxide, and lauryl peroxide; and at least one selected from the group consisting of azo compounds such as azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile), but is not limited thereto.
[103]
The organic peroxide may be an organic peroxide having a 1-hour half-life temperature of 120 to 135 °C, for example, 120 to 130 °C, 120 to 125 °C, preferably 121 °C. The "one-hour half-life temperature" means a temperature at which the half-life of the cross-linking agent becomes one hour. According to the one-hour half-life temperature, the temperature at which the radical initiation reaction efficiently occurs is different, and therefore, when an organic peroxide having a one-hour half-life temperature in the above-described range is used as a crosslinking agent, the lamination process temperature for manufacturing an optoelectronic device In the radical initiation reaction, that is, the crosslinking reaction can proceed effectively.
[104]
The crosslinking agent may be included in an amount of 0.01 to 1 parts by weight, for example, 0.05 to 0.55 parts by weight, 0.1 to 0.5 parts by weight, or 0.15 to 0.45 parts by weight based on 100 parts by weight of the composition for the encapsulant film. When the amount of the crosslinking agent is less than 0.01 part by weight, the effect of improving the heat resistance properties is insignificant, and when it exceeds 1 part by weight, the moldability of the encapsulant film decreases, which may cause process restrictions, and may affect the physical properties of the encapsulant.
[105]
[106]
In addition, the composition for the encapsulant film may include a crosslinking aid in addition to the crosslinking agent. By including the crosslinking aid, the degree of crosslinking between the composition for an encapsulant film by the above-described crosslinking agent can be increased, and thus the heat resistance durability of the final product, for example, the encapsulant film can be further improved.
[107]
As the crosslinking aid, various crosslinking aids known in the art may be used, for example, a compound containing at least one unsaturated group such as an allyl group or a (meth)acryloxy group may be used.
[108]
The compound containing the allyl group may be exemplified by polyallyl compounds such as triallyl isocyanurate (TAIC), triallyl cyanurate, diallyl phthalate, diallyl fumarate or diallyl maleate, and the like, The compound containing the meth) acryloxy group may be exemplified by poly(meth)acryloxy compounds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate, and trimethylolpropane trimethacrylate, but is not limited thereto. .
[109]
The crosslinking aid may be included in an amount of 0.01 to 0.5 parts by weight, for example, 0.01 to 0.3 100, 0.015 to 0.2 100, or 0.016 to 0.16 parts by weight, based on 100 parts by weight of the composition for the encapsulant film. When the amount of the crosslinking aid is less than 0.01 parts by weight, the effect of improving the heat resistance properties is insignificant, and when it exceeds 0.5 parts by weight, a problem affecting the physical properties of the final product, such as an encapsulant film, may occur and the production cost may increase.
[110]
[111]
In addition, the composition for the encapsulant film may further include a silane coupling agent in addition to the ethylene/alpha-olefin copolymer, a crosslinking agent, and a crosslinking aid.
[112]
Examples of the silane coupling agent include N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxy At least one selected from the group consisting of silane, γ-glycidoxypropyltrimethoxysilane and γ-methacryloxypropyltrimethoxysilane (MEMO) may be used.
[113]
The silane coupling agent may be included in an amount of 0.1 to 1 part by weight based on 100 parts by weight of the composition for an encapsulant film. When the amount is less than 0.1 part by weight, the adhesion to glass is poor when manufacturing the solar module, so moisture immersion becomes easy, so the long-term performance of the module cannot be guaranteed.
[114]
[115]
In addition, the composition for the encapsulant film may further include an unsaturated silane compound and an amino silane compound.
[116]
The unsaturated silane compound is grafted onto the main chain including the polymerization unit of the monomer of the ethylene/alpha-olefin copolymer of the present invention in the presence of a radical initiator, etc., and polymerized in a silane-modified resin composition or an aminosilane-modified resin composition may be included as
[117]
The unsaturated silane compound is vinyltrimethoxysilane, vinyltriethoxysilane, vinyltripropoxysilane, vinyltriisopropoxysilane, vinyltributoxysilane, vinyltripentoxysilane, vinyltriphenoxysilane, or vinyl It may be triacetoxy silane and the like, and as an example, vinyl trimethoxy silane or vinyl triethoxy silane may be used, but the present invention is not limited thereto.
[118]
In addition, the amino silane compound is an unsaturated silane compound grafted to the main chain of the copolymer in the grafting modification step of the ethylene/alpha-olefin copolymer, for example, a reactive functional group such as an alkoxy group of vinyltriethoxysilane. By acting as a catalyst for accelerating the decomposition reaction, the adhesive strength with the upper and lower glass substrates or the back sheet composed of a fluororesin or the like can be further improved. In addition, the amino silane compound may provide a moiety having an amine functional group to the amino silane-modified resin composition by directly participating as a reactant in the copolymerization reaction.
[119]
The amino silane compound is not particularly limited as long as it is a silane compound containing an amine group and is a primary amine or a secondary amine. For example, as the amino silane compound, aminotrialkoxysilane, aminodialkoxysilane, etc. may be used. Examples include 3-aminopropyltrimethoxysilane (APTMS), 3-aminopropyltriethoxysilane. (3-aminopropyltriethoxysilane; APTES), bis[(3-triethoxysilyl)propyl]amine, bis[(3-trimethoxysilyl)propyl]amine, 3-aminopropylmethyldiethoxysilane, 3-aminopropylmethyl Dimethoxysilane, N-[3-(trimethoxysilyl)propyl]ethylenediamine (N-[3-(Trimethoxysilyl)propyl]ethylenediamine; DAS), aminoethylaminopropyltriethoxysilane, aminoethylaminopropylmethyldime Toxysilane, aminoethylaminopropylmethyldiethoxysilane, aminoethylaminomethyltriethoxysilane, aminoethylaminomethylmethyldiethoxysilane, diethylenetriaminopropyltrimethoxysilane, diethylenetriaminopropyltriethoxysilane, Diethylenetriaminopropylmethyldimethoxysilane, diethyleneaminomethylmethyldiethoxysilane, (N-phenylamino)methyltrimethoxysilane, (N-phenylamino)methyltriethoxysilane, (N-phenylamino)methyl Methyldimethoxysilane, (N-phenylamino)methylmethyldiethoxysilane, 3-(N-phenylamino)propyltrimethoxysilane, 3-(N-phenylamino)propyltriethoxysilane, 3-(N- at least one selected from the group consisting of phenylamino)propylmethyldimethoxysilane, 3-(N-phenylamino)propylmethyldiethoxysilane, and N-(N-butyl)-3-aminopropyltrimethoxysilane can be heard The amino silane compounds may be used alone or in combination.
[120]
The content of the unsaturated silane compound and/or the amino silane compound is not particularly limited.
[121]
[122]
In addition, the composition for the encapsulant film may further include at least one additive selected from a light stabilizer, a UV absorber, a heat stabilizer, and the like, if necessary.
[123]
The light stabilizer may serve to prevent photooxidation by catching active species that initiate photodegradation of the resin depending on the application to which the composition is applied. The type of light stabilizer that can be used is not particularly limited, and, for example, a known compound such as a hindered amine-based compound or a hindered piperidine-based compound may be used.
[124]
The UV absorber absorbs ultraviolet rays from sunlight or the like and converts them into harmless thermal energy in molecules, depending on the use of the composition, and may serve to prevent excitation of active species initiating photodegradation in the composition. Specific types of UV absorbers that can be used are not particularly limited, and for example, inorganic UV absorbers such as benzophenone-based, benzotriazole-based, acrylnitrile-based, metal complex salt-based, hindered amine-based, ultra-fine titanium oxide or ultra-fine zinc oxide. One type or a mixture of two or more types, such as an absorbent, can be used.
[125]
In addition, examples of the heat stabilizer include tris(2,4-di-tert-butylphenyl)phosphite, bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl ester phosphorous acid, tetrakis (2,4-di-tert-butylphenyl)[1,1-biphenyl]-4,4'-diylbisphosphonate and bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite phosphorus-based thermal stabilizers; and a lactone-based thermal stabilizer such as a reaction product of 8-hydroxy-5,7-di-tert-butyl-furan-2-one and o-xylene, and one or two or more of the above may be used. have.
[126]
The content of the light stabilizer, the UV absorber and/or the 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 or density of the additive, etc., and is usually within the range of 0.01 to 5 parts by weight based on 100 parts by weight of the total solid content of the composition for an encapsulant film. can be appropriately adjusted.
[127]
In addition, the composition for an encapsulant film of the present invention may further include various additives known in the art according to the use to which the resin component is applied in addition to the above components.
[128]
[129]
In addition, the present invention provides an encapsulant film comprising the composition for the encapsulant film.
[130]
The encapsulant film of the present invention may be manufactured by molding the composition for encapsulant film into a film or sheet shape. Such a molding method is not particularly limited, and for example, it may be manufactured by forming a sheet or filming it in a conventional process such as a T-die process or extrusion. For example, the production of the encapsulant film is performed in an in situ process using an apparatus in which the production of the modified resin composition using the composition for the encapsulant film and the film forming or sheet forming process are connected to each other. can do.
[131]
The thickness of the encapsulant film can be adjusted to about 10 to 2,000 μm, or about 100 to 1,250 μm, or about 100 to 1,250 μm, in consideration of the support efficiency and the possibility of breakage of the device in the optoelectronic device, the weight reduction or workability of the device, and the like, depending on the specific use. can be changed.
[132]
[133]
solar cell module
[134]
In addition, the present invention provides a solar cell module including the encapsulant film. In the present invention, the solar cell module fills the gap between the solar cells arranged in series or in parallel with the encapsulant film of the present invention, a glass surface is disposed on the surface where sunlight strikes, and the back surface is protected with a back sheet. However, the present invention is not limited thereto, and various types and shapes of solar cell modules manufactured including an encapsulant film in the art may be applied to the present invention.
[135]
The glass surface may use tempered glass to protect the solar cell from external impact and prevent breakage, and low iron tempered glass with a low iron content to prevent reflection of sunlight and increase the transmittance of sunlight. can be used, but is not limited thereto.
[136]
The back sheet is a weather-resistant film that protects the back surface of the solar cell module from the outside, and for example, a fluorine-based resin sheet, a metal plate or metal foil such as aluminum, a cyclic olefin-based resin sheet, a polycarbonate-based resin sheet, a poly(meth)acrylic resin a sheet, a polyamide-based resin sheet, a polyester-based resin sheet, a composite sheet obtained by laminating a weather resistant film and a barrier film, and the like, but is not limited thereto.
[137]
In addition, the solar cell module of the present invention may be manufactured without limitation according to a method known in the art, except for including the encapsulant film described above.
[138]
The solar cell module of the present invention is manufactured using an encapsulant film having excellent volume resistance, and it is possible to prevent electrons in the solar cell module from moving through the encapsulant film to prevent leakage of current to the outside, and thus the insulation deteriorates This can greatly suppress the PID (Potential Induced Degradation) phenomenon in which leakage current occurs and the output of the module decreases rapidly.
[139]
[140]
Example
[141]
Hereinafter, the present invention will be described in more detail by way of Examples. However, the following examples are provided to illustrate the present invention, and the scope of the present invention is not limited thereto.
[142]
[143]
Preparation of catalyst
[144]
(1) Preparation of Ligand Compound
[145]

[146]
In a 100 mL Schlenk flask, add 4.65 g (15.88 mmol) of the compound of chloro(1,2-dimethyl-6,7-dihydro-3H-benzo[b]cyclopenta[d]thiophen-3-yl)dimethylsilane After quantitative addition, 80 mL of THF was added. After adding tBuNH 2 (4 eq, 6.68 mL) at room temperature, the reaction was conducted at room temperature for 3 days. After the reaction, THF was removed and filtered with hexane. After solvent drying, a yellow liquid was obtained in a yield of 4.50 g (86%).
[147]
1 H NMR (in CDCl 3 , 500 MHz): δ 7.99 (d, 1H), δ 7.83 (d, 1H), δ 7.35 (dd, 1H), δ 7.24 (dd, 1H), δ 3.49 (s, 1H) ), δ 2.37(s, 3H), δ 2.17(s, 3H), δ 1.27(s, 9H), δ 0.19(s, 3H), δ −0.17(s, 3H).
[148]
(2) Preparation of transition metal compound
[149]
[Formula 1]
[150]

[151]
The ligand compound (1.06 g, 3.22 mmol/1.0 eq) and 16.0 mL (0.2 M) of MTBE were placed in a 50 mL Schlenk flask and first stirred. At -40 °C, n-BuLi (2.64 mL, 6.60 mmol/2.05 eq, 2.5 M in THF) was added and reacted at room temperature overnight. After that, MeMgBr (2.68 mL, 8.05 mmol/2.5eq, 3.0M in diethyl ether) was slowly added dropwise at -40 °C, and TiCl 4 (2.68 mL, 3.22 mmol/1.0eq, 1.0M in toluene) was added in this order. The reaction was carried out at room temperature overnight. Then, the reaction mixture was filtered through Celite using hexane. After solvent drying, a brown solid was obtained in a yield of 1.07 g (82%).
[152]
1 H-NMR (in CDCl 3 , 500 MHz): δ 7.99 (d, 1H), δ 7.68 (d, 1H), δ 7.40 (dd, 1H), δ 7.30 (dd, 1H), δ 3.22 (s, 1H), δ 2.67(s, 3H), δ 2.05(s, 3H), δ 1.54(s, 9H), δ 0.58(s, 3H), δ 0.57(s, 3H), δ 0.40(s, 3H) , δ −0.45 (s, 3H).
[153]
[154]
Preparation Example 1
[155]
In a 1.5 L continuous process reactor, 5.00 kg/h of a hexane solvent and 1.30 kg/h of 1-butene were added and preheated at 120 °C. Triisobutylaluminum (Tibal, Triisobutylaluminum, 60 μmol/min), the transition metal compound of Formula 1 (0.35 μmol/min), dimethylanilinium tetrakis (pentafluorophenyl) borate promoter (1.05 μmol/min) ) were simultaneously introduced into the reactor. Then, ethylene (0.87 kg/h) and hydrogen gas (20 cc/min) were introduced into the reactor and maintained at 150° C. for at least 60 minutes in a continuous process at a pressure of 89 bar to proceed with a copolymerization reaction to obtain a copolymer. . After drying in a vacuum oven for 12 hours or more, an ethylene/alpha-olefin copolymer was prepared.
[156]
Preparation Examples 2 to 8
[157]
An ethylene/alpha-olefin copolymer was prepared in the same manner as in Preparation Example 1, except that polymerization conditions were changed as shown in Table 1 below.
[158]
[Table 1]
C2 Alpha-olefins Cat. Co-cat. Tibal menstruum polymerization temperature
kg/h Kinds kg/h μmol/min μmol/min kg/h ℃
Preparation Example 1 0.87 1-C4 1.30 0.35 1.05 60 5.00 150
Preparation 2 0.87 1-C4 0.90 0.15 0.45 20 5.00 140
Preparation 3 0.87 1-C4 0.90 0.25 0.75 30 7.00 150
Preparation 4 0.87 1-C4 1.00 0.20 0.60 30 5.00 145
Preparation 5 0.87 1-C4 1.50 0.44 1.32 30 4.65 160
Preparation 6 0.87 1-C8 0.48 0.48 0.43 30 5.00 160
Preparation 7 0.87 1-C8 0.50 0.55 1.65 30 5.00 160
Preparation 8 0.87 1-C8 1.30 0.70 2.10 60 4.00 160
[159]
Example 1
[160]
Step (S2)
[161]
20 g of the ethylene/alpha-olefin copolymer of Preparation Example 1 and 400 mL of heptane were mixed to prepare a composition, and then stirred at 80° C. until the copolymer was completely dissolved and visually transparent.
[162]
Step (S3)
[163]
After lowering the temperature to room temperature, the transparent composition was added dropwise to 1.4 L of isopropyl alcohol while stirring. After completion of the dropwise addition, the liquid portion was removed and the solid precipitated portion was separated, followed by vacuum drying at 110° C. for 48 hours.
[164]
The steps (S2) and (S3) were alternately repeated 4 times each to prepare an ethylene/alpha-olefin copolymer.
[165]
Examples 2 to 8, Comparative Examples 1 to 8
[166]
An ethylene/alpha-olefin copolymer was prepared in the same manner as in Example 1, except that the type of ethylene/alpha-olefin copolymer and the number of steps (S2) and (S3) were changed as shown in Table 2 below. .
[167]
[Table 2]
Ethylene/alpha-olefin copolymer Step (S2) number of times Step (S3) number of times
Example 1 Preparation Example 1 4 4
Example 2 Preparation 2 4 4
Example 3 Preparation 3 4 4
Example 4-1 Preparation 4 3 3
Example 4-2 Preparation 4 4 4
Example 5-1 Preparation 5 One One
Example 5-2 Preparation 5 2 2
Example 5-3 Preparation 5 3 3
Example 5-4 Preparation 5 4 4
Example 6 Preparation 6 4 4
Example 7 Preparation 7 4 4
Example 8 Preparation 8 4 4
Comparative Example 1 Preparation Example 1 0 0
Comparative Example 2 Preparation 2 0 0
Comparative Example 3-1 Preparation 3 0 0
Comparative Example 3-2 Preparation 3 0 One
Comparative Example 4 Preparation 4 0 0
Comparative Example 5 Preparation 5 0 0
Comparative Example 6 Preparation 6 0 0
Comparative Example 7-1 Preparation 7 0 0
Comparative Example 7-2 Preparation 7 One 0
Comparative Example 8 Preparation 8 0 0
[168]
Experimental Example 1
[169]
The ethylene/alpha-olefin copolymers prepared in Examples and Comparative Examples were evaluated for physical properties according to the following method, and are shown in Table 3.
[170]
[171]
(1) Stress relaxation time
[172]
Using TA's ARES-G2 Rheometer, the complex viscosity according to the angular velocity of the copolymer was obtained with a strain of 5% in the angular velocity range of 190 ° C., 0.1 to 500 rad/s, and the stress relaxation time was determined by the following Carreau-Yasuda equation was calculated by fitting.
[173]

[174]
η ( γ ): viscosity
[175]
η ∞ : infinite viscosity
[176]
η 0 : zero-shear viscosity
[177]
λ: stress relaxation time
[178]
γ : shear-rate
[179]
α: material constants
[180]
n: shear thinning index
[181]
[182]
(2) Weight average molecular weight (Mw) and molecular weight distribution (MWD)
[183]
The weight average molecular weight (Mw) and the number average molecular weight (Mn) were respectively measured using gel permeation chromatography (GPC, Gel Permeation Chromatography), and the molecular weight distribution was obtained by dividing the weight average molecular weight (Mw) by the number average molecular weight (Mn). Calculated.
[184]
- Column: PL Olexis
[185]
- Solvent: TCB (Trichlorobenzene)
[186]
- Flow rate: 1.0 mL/min
[187]
- Sample concentration: 1.0 mg/mL
[188]
- Injection volume: 200 μL
[189]
- Column temperature: 160 ℃
[190]
- Detector: Agilent High Temperature RI detector
[191]
- Standard: polystyrene (corrected by cubic function)
[192]
[193]
(3) Density (g/cm 3 )
[194]
Measured according to ASTM D-792.
[195]
[196]
(4) Melt Index (MI 2.16 , g/10min)
[197]
It was measured according to ASTM D-1238 (Condition E, 190°C, 2.16 kg load).
[198]
[199]
[Table 3]
Stress relaxation time Mw (g/mol) MWD Density (g/cm 3 ) Melt Index (g/10min)
Example 1 4.9 73,000 2.08 0.864 4.7
Example 2 4.8 72,000 2.03 0.873 5.0
Example 3 4.3 58,000 2.02 0.875 14.3
Example 4-1 4.1 49,000 2.16 0.880 18.5
Example 4-2 3.5 50,000 2.00 0.880 17.1
Example 5-1 8.0 44,000 2.25 0.871 30.0
Example 5-2 5.3 44,000 2.19 0.871 29.5
Example 5-3 4.2 46,000 2.10 0.871 27.2
Example 5-4 3.0 46,000 2.05 0.871 25.4
Example 6 9.2 83,000 1.92 0.901 2.4
Example 7 4.4 70,000 2.02 0.902 6.0
Example 8 3.2 45,000 2.15 0.872 27.8
Comparative Example 1 53.1 69,000 2.31 0.864 5.0
Comparative Example 2 87.1 69,000 2.30 0.873 5.5
Comparative Example 3-1 25.2 56,000 2.27 0.875 15.6
Comparative Example 3-2 24.3 56,000 2.25 0.875 15.2
Comparative Example 4 16.9 48,000 2.36 0.880 20.2
Comparative Example 5 12.1 43,000 2.37 0.871 33.8
Comparative Example 6 190.2 79,000 2.20 0.901 2.8
Comparative Example 7-1 70.0 67,000 2.29 0.902 6.4
Comparative Example 7-2 67.2 67,000 2.27 0.902 6.2
Comparative Example 8 4.8 41,000 2.54 0.872 36.5
[200]
As summarized in the table above, in the examples in which the ethylene/alpha-olefin copolymer was prepared by performing the organic solvent dissolution and alcohol precipitation steps according to the present invention, the stress relaxation time, Mw, and MWD are all specific values ​​in the present invention. It was confirmed that the range was satisfied.
[201]
In particular, comparing Examples 4-1 and 4-2 and Examples 5-1 to 5-4, as the number of repetitions of organic solvent dissolution and alcohol precipitation increases, ethylene/alpha-olefin air having a high molecular weight and narrow MWD The coalescence was produced, and the stress relaxation time became shorter and shorter.
[202]
Meanwhile, in the case of Comparative Examples, the organic solvent dissolution and alcohol precipitation steps were not performed after polymerization of ethylene and alpha-olefin monomers. In Comparative Examples 1 to 7-2, etc., the stress relaxation time was significantly higher than in Examples, and in Comparative Example 8, the MWD was wide, confirming that it was outside the requirements defined in the present invention.
[203]
In particular, in Comparative Example 3-2, in which both the organic solvent and the alcohol were not used, as well as Comparative Example 3-2, which was directly precipitated in alcohol without dissolving it in the organic solvent, the copolymer chain was not sufficiently released and thus did not properly precipitate in the alcohol, resulting in a low molecular weight portion This was not removed, so it was confirmed that the stress relaxation time was still long. Also, in Comparative Example 7-2, which was dissolved in an organic solvent and not precipitated in alcohol, the removal of the branched low-molecular-weight portion was not achieved, and thus the stress relaxation time was long.
[204]
[205]
Experimental Example 2
[206]
6 g of the ethylene/alpha-olefin copolymer was placed in a 0.5T square mold, the front and rear surfaces were covered with 3T steel plates, and then put into a hot press machine. 190 ℃, 25 N/cm 2 (240 sec), 6 times of degassing / degassing, 190 ℃ 151 N/cm 2 After continuous treatment at 151 N/cm 2 for 240 sec, cooling to 30 ℃ while lowering 15 ℃ per minute, at this time The pressure was maintained at 151 N/cm 2 . 30 ℃, 151 N/cm 2 It was maintained for 300 seconds to complete the preparation of the specimen.
[207]
For the sample thus prepared, the volume resistance and light transmittance were measured and shown according to the following method.
[208]
[209]
(1) Volume resistance (Ω·cm)
[210]
Measurements were made while applying a voltage of 1000V for 600 seconds using an Agilent 4339B High-Resistance meter (manufactured by Agilent Technology Co., Ltd.) at a temperature of 23±1° C. and a humidity of 50±3%.
[211]
[212]
(2) light transmittance (%)
[213]
The light transmittance at 550 nm was measured using a Shimadzu UV-3600 spectrophotometer.
[214]
- Measuring mode: transmittance
[215]
- Wavelength interval: 1 nm
[216]
- Measuring speed: medium
[217]
[Table 4]
Volume resistance (Ω·cm) Light transmittance (%)
Example 1 2.60 × 10 16 91.1
Comparative Example 1 3.10 × 10 14 91.0
[218]
[Table 5]
Volume resistance (Ω·cm) Light transmittance (%)
Example 2 5.20 × 10 16 90.6
Comparative Example 2 2.50 × 10 14 90.5
[219]
[Table 6]
Volume resistance (Ω·cm) Light transmittance (%)
Example 3 7.50 × 10 16 90.5
Comparative Example 3-1 1.00 × 10 14 90.4
Comparative Example 3-2 2.10 × 10 14 90.4
[220]
[Table 7]
Volume resistance (Ω·cm) Light transmittance (%)
Example 4-1 3.40 × 10 16 89.3
Example 4-2 4.50 × 10 16 89.5
Comparative Example 4 1.40 × 10 14 89.2
[221]
[Table 8]
Volume resistance (Ω·cm) Light transmittance (%)
Example 5-1 8.90 × 10 15 90.2
Example 5-2 2.20 × 10 16 90.2
Example 5-3 3.00 × 10 16 90.3
Example 5-4 4.10 × 10 16 90.5
Comparative Example 5 3.20 × 10 14 90.2
[222]
[Table 9]
Volume resistance (Ω·cm) Light transmittance (%)
Example 6 9.80 × 10 16 89.0
Comparative Example 6 4.20 × 10 14 88.8
[223]
[Table 10]
Volume resistance (Ω·cm) Light transmittance (%)
Example 7 1.60 × 10 16 88.6
Comparative Example 7-1 4.60 × 10 14 88.5
Comparative Example 7-2 4.42 × 10 14 88.5
[224]
[Table 11]
Volume resistance (Ω·cm) Light transmittance (%)
Example 8 1.50 × 10 16 90.4
Comparative Example 8 7.80 × 10 14 90.2
[225]
The above tables are arranged in correspondence with Examples and Comparative Examples using the same manufacturing example. As described above, it was confirmed that all of the ethylene/alpha-olefin copolymers prepared according to the present invention can realize excellent volume resistance and light transmittance. It was found that the volume resistance was decreased in all cases outside the scope of the present invention, such as when the MWD was wide.
[226]
As such, the ethylene/alpha-olefin copolymer satisfying all of the stress relaxation time, Mw, and MWD defined in the present invention was able to implement excellent volume resistance and light transmittance without using a separate additive.

WE CLAIMS

[Claim 1]Ethylene / alpha-olefin copolymer satisfying the following conditions (a) to (c): (a) 190 ° C., 0.1 to 500 rad / s Stress relaxation time at a shear rate condition (Characteristic Relaxation Time, λ) is 10.0 ms less than (millisecond); (b) a weight average molecular weight of 40,000 to 150,000 g/mol; and (c) the molecular weight distribution is from 1.5 to 2.5.
[Claim 2]
The ethylene/alpha-olefin copolymer according to claim 1, wherein the stress relaxation time is 1.0 to 9.5 ms.
[Claim 3]
The ethylene/alpha-olefin copolymer according to claim 1, wherein the weight average molecular weight is 41,000 to 130,000 g/mol.
[Claim 4]
The ethylene/alpha-olefin copolymer according to claim 1, wherein the molecular weight distribution is 1.5 to 2.4.
[Claim 5]
The ethylene/alpha-olefin copolymer according to claim 1, wherein the density is 0.850 to 0.910 g/cc.
[Claim 6]
The ethylene/alpha-olefin copolymer according to claim 1, wherein the melt index (190°C, 2.16 kg load condition) is 0.1 to 50 g/10 min.
[Claim 7]
The method according to claim 1, wherein the alpha-olefin is 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, and 1-eicosene ethylene / alpha-olefin copolymer comprising at least one selected from the group consisting of.
[Claim 8]
Encapsulant film comprising an ethylene/alpha-olefin copolymer satisfying the following conditions (a) to (c): (a) Stress relaxation time at 190 ° C., 0.1 to 500 rad/s shear rate conditions (Characteristic Relaxation Time) , λ) is less than 10.0 ms (millisecond); (b) a weight average molecular weight of 40,000 to 150,000 g/mol; and (c) the molecular weight distribution is from 1.5 to 2.5.
[Claim 9]
The encapsulant film of claim 8, further comprising at least one selected from the group consisting of a crosslinking agent, a crosslinking aid, a silane coupling agent, an unsaturated silane compound, an amino silane compound, a light stabilizer, a UV absorber, and a heat stabilizer.
[Claim 10]
A solar cell module comprising the encapsulant film of claim 8 .