JP2012025945A - Resin composition for extrusion molding, sealing material for solar cell module and solar cell module using the same, water-shielding sheet, or tarpaulin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for extrusion molding containing an ethylene/α-olefin copolymer and an organic peroxide, being excellent in productivity of a solar cell sealing material, a water-shielding sheet and tarpaulin, and being excellent in heat-resistance, transparency and flexibility.SOLUTION: The resin composition for extrusion molding is provided, which is characterized in that it contains the ethylene/α-olefin copolymer component (A) having characteristics of the following (a1)-(a5) and the organic peroxide component (B). (a1): The density is 0.860-0.920 g/cm; (a2): the ratio (Mz/Mn) of the Z-average molecular weight (Mz) and the number-average molecular weight (Mn) determined by gel permeation chromatography (GPC) is 8.0 or less; (a3): the melt viscosity (η) measured at 100°C at a shear rate of 2.43×10 sis 1.2×10poise or higher; (a4): the melt viscosity (η) measured at 100°C at a shear rate of 2.43×10sis 2.0×10poise or higher; and (a5): the branch number (N) by the co-monomer in the polymer satisfies a relational expression (a) with the tensile modulus (E) of the sheet.

Description

  The present invention relates to a resin composition for extrusion molding, a sealing material for a solar cell module using the resin composition, a solar cell module, a water shielding sheet, or a tarpaulin, and more specifically, an ethylene / α-olefin copolymer and an organic polymer. It contains oxides and is excellent in productivity of solar cell module sealing and solar cell module materials, water shielding sheets, tarpaulins, etc., and relates to a resin composition for extrusion molding that is excellent in heat resistance, transparency, and flexibility. is there.

  Ethylene / α-olefin copolymers are used in various applications such as sealing materials for solar cell modules and sheets used outdoors because of their good transparency and flexibility.

  For example, in solar cell modules, from the viewpoint of price, workability, moisture resistance, etc., as an encapsulating material, an organic peroxide is blended with an ethylene / vinyl acetate copolymer (EVA) having a high vinyl acetate content and crosslinked. A composition having a structure is employed (see, for example, Patent Document 1). However, ethylene / vinyl acetate copolymer (EVA) resin, when used over a long period of time, has deteriorated moisture resistance due to deterioration / deterioration such as yellowing, cracking and foaming, and power generation due to corrosion of solar cells, etc. The amount was reduced. These are considered to be easily affected by sunlight and moisture because the EVA resin has an ester structure with high hydrolyzability.

Therefore, as a sealing material for a solar cell module, a material composed of an amorphous or low crystalline α-olefin copolymer having a crystallinity of 40% or less has been proposed (see Patent Document 2). In this Patent Document 2, it is exemplified that a low crystalline ethylene / butene copolymer is mixed with an organic peroxide and a sheet is produced at a processing temperature of 100 ° C. using a profile extruder. Since processing temperature is low, there exists a problem that productivity cannot be improved.
Moreover, as a sealing material for solar cell modules, (a) a density of less than about 0.90 g / cc, (b) a 2% secant coefficient of less than about 150 megapascals (mPa) as measured by ASTM D-882-02 (C) a melting point of less than about 95 ° C., (d) an α-olefin content of at least about 15 and less than about 50% by weight based on the weight of the polymer, (e) a Tg of less than about −35 ° C., and (f) A polymer material containing a polyolefin copolymer that satisfies one or more conditions of at least about 50 SCBDI has been proposed (see Patent Document 3).
In the solar cell module, the solar cell encapsulant tends to become thinner as the solar cell element becomes thinner. At that time, when an impact is applied from the upper or lower protective material side of the solar cell sealing material, the wiring is likely to be disconnected. In order to improve it, it is required to increase the rigidity of the sealing material. However, in the polymer material of Patent Document 3, if the rigidity is increased, there is a problem that the crosslinking efficiency is deteriorated.

On the other hand, in the waste disposal site, a large number of water shielding sheets are laid so as to completely cover the surface of the disposal site. The water shielding sheet must not only have heat resistance, but also be flexible so that it can be handled on site. In addition, in order to increase the area by connecting the water-impervious sheets, the water-impervious sheet is fused and integrated by heat, and the fused part has the same strength, water-imperviousness and durability as the water-impervious sheet. It is required to have sex.
Furthermore, as a signboard suitable for a long-term outdoor display such as a banner, a tarpaulin in which a fiber woven fabric is used as a base fabric and a layer of a polyethylene resin composition is laminated on at least one surface thereof is used. Tarpaulins are stronger than fiber knitted fabrics and are resistant to rain, so they are used not only for signage but also as construction site sheets, agricultural and livestock industry houses, and general tent materials. Therefore, the tarpaulin is required to have the same strength, water shielding and durability as the water shielding sheet.
However, according to the conventional techniques as described above, a resin composition for extrusion molding excellent in productivity, heat resistance, transparency and flexibility cannot be obtained, and a water shielding sheet and tarpaulin having sufficient performance have not been developed. .

JP 58-023870 A JP 2006-210906 A JP 2010-504647 A

  The object of the present invention is to contain an ethylene / α-olefin copolymer and an organic peroxide, and is excellent in productivity of solar cell encapsulant and solar cell module, water shielding sheet, tarpaulin, etc., heat resistant, transparent It is providing the resin composition for extrusion molding which is excellent in property and a softness | flexibility.

  As a result of intensive studies to solve the above problems, the present inventors have selected an ethylene / α-olefin copolymer having specific properties polymerized using a metallocene catalyst or the like as a resin component, By compounding an oxide, a resin composition for extrusion molding having excellent heat resistance, transparency, and flexibility can be obtained. By using this, a sealing material for a solar cell module, a solar cell module, a water shielding sheet, tarpaulin, etc. As a result, the present invention has been completed.

That is, according to 1st invention of this invention, the resin composition for extrusion molding characterized by containing the following component (A) and component (B) is provided.
Component (A): ethylene / α-olefin copolymer (a1) having the following properties (a1) to (a5): Density of 0.860 to 0.920 g / cm ³
(A2) The ratio (Mz / Mn) of Z average molecular weight (Mz) and number average molecular weight (Mn) determined by gel permeation chromatography (GPC) was 8.0 or less (a3) Shear measured at 100 ° C. rate melt viscosity at _{^{2.43 × 10s -1 (η * 1}} ) was measured at 1.2 × ¹⁰ 5 poise or (a4) 100 ℃, shear rate at 2.43 × ¹⁰ 2 ^{s -1} The melt viscosity (η ^* ₂ ) is 2.0 × 10 ⁴ poise or more (a5) The number of branches (N) due to the comonomer in the polymer satisfies the following formula (a).
Formula (a): N ≧ −0.67 × E + 53
(Where N is the number of branches per 1000 carbon atoms in total of the main chain and side chain measured by NMR, and E is the tensile modulus of the sheet measured in accordance with ISO 1184-1983.) )
Component (B): Organic peroxide

Further, according to the second invention of the present invention, in the first invention, (a5) the number of branches (N) due to the comonomer in the polymer satisfies the following formula (a ′): A resin composition is provided.
Formula (a ′): −0.67 × E + 100 ≧ N ≧ −0.67 × E + 53
(Where N is the number of branches per 1000 carbon atoms in total of the main chain and side chain measured by NMR, and E is the tensile modulus of the sheet measured in accordance with ISO 1184-1983.) )
According to a third invention of the present invention, in the first or second invention, (a5) the number of branches (N) due to the comonomer in the polymer satisfies the following formula (a ″): An extrusion molding resin composition is provided.
Formula (a ″): −0.67 × E + 80 ≧ N ≧ −0.67 × E + 53
(Where N is the number of branches per 1000 carbon atoms in total of the main chain and side chain measured by NMR, and E is the tensile modulus of the sheet measured in accordance with ISO 1184-1983.) )

Moreover, according to the 4th invention of this invention, the resin composition for extrusion molding characterized by containing the following component (A) and a component (B) is provided.
Component (A): ethylene / α-olefin copolymer (a1) having the following characteristics (a1) to (a4) and (a6): density is 0.860 to 0.920 g / cm ³
(A2) The ratio (Mz / Mn) of Z average molecular weight (Mz) and number average molecular weight (Mn) determined by gel permeation chromatography (GPC) was 8.0 or less (a3) Shear measured at 100 ° C. rate melt viscosity at _{^{2.43 × 10s -1 (η * 1}} ) was measured at 1.2 × ¹⁰ 5 poise or (a4) 100 ℃, shear rate at 2.43 × ¹⁰ 2 ^{s -1} Melt viscosity (η ^* ₂ ) is 2.0 × 10 ⁴ poise or more (a6) Flow ratio (FR): I10 which is MFR measured value at ₁₀ ° C. load at 190 ° C. and 2.16 kg load at 190 ° C. Ratio (I ₁₀ / I _2.16 ) with I _2.16 which is MFR measurement value is less than 7.0 Component (B): Organic peroxide

According to a fifth aspect of the present invention, in the fourth aspect, the flow ratio (FR) of the characteristic (a6) is 5.0 to 6.2. A resin composition is provided.
According to the sixth invention of the present invention, in any one of the first to fifth inventions, the content of the component (B) is 0.2 to 5 parts by weight with respect to 100 parts by weight of the component (A). The resin composition for extrusion molding characterized by being a part is provided.
According to a seventh invention of the present invention, there is provided an extrusion molding resin composition characterized by further comprising the following component (C) in any one of the first to sixth inventions. .
Component (C): Hindered amine light stabilizer

According to an eighth aspect of the present invention, in any one of the first to seventh aspects, the component (A) is an ethylene / propylene copolymer, an ethylene / 1-butene copolymer, or ethylene / 1. -A resin composition for extrusion molding characterized by being a hexene copolymer.
According to a ninth aspect of the present invention, in any one of the first to seventh aspects, the component (A) is an ethylene / propylene / 1-hexene terpolymer. A resin composition for molding is provided.
According to a tenth aspect of the present invention, in any one of the first to ninth aspects, a solar cell encapsulant comprising an extrusion molding resin composition is provided.
Moreover, according to the 11th invention of this invention, the solar cell module using the solar cell sealing material of 10th invention is provided.

On the other hand, according to the twelfth aspect of the present invention, there is provided a water shielding sheet formed by extruding the resin composition for extrusion molding according to any one of the first to ninth aspects into a sheet shape.
Furthermore, according to the thirteenth aspect of the present invention, there is provided a tarpaulin which is laminated on at least one surface of a base fabric using the resin composition for extrusion molding according to any one of the first to ninth aspects. .

The resin composition for extrusion molding according to the present invention is mainly composed of an ethylene / α-olefin copolymer having a specific density, molecular weight distribution, and melt viscosity characteristics, and an organic peroxide is blended therein. When a resin composition is made into a sheet, the ethylene / α-olefin copolymer is crosslinked in a relatively short time to have sufficient adhesive strength, and a good balance between rigidity and crosslinking efficiency is obtained. The module can be easily formed as a material, and the manufacturing cost can be reduced. Moreover, the obtained solar cell module becomes excellent in transparency, flexibility, weather resistance, etc., and it can be expected to maintain stable conversion efficiency for a long period of time.
Furthermore, since the resin composition for extrusion molding of the present invention is excellent in flexibility, weather resistance, etc., it is easy to handle on the site as a water shielding sheet that completely covers the surface of the disposal site at the waste disposal site, and the water shielding sheet. Since the portions overlapping each other can be fused and integrated by heat, the fused portion also has exactly the same strength, water shielding and durability as the water shielding sheet. Moreover, since the resin composition for extrusion molding has transparency, it is durable not only as a tarpaulin (signboard) that makes use of the color of the fabric, but it can be installed outdoors as a tent for a long time.

It is a graph which shows the range of Formula (a) which prescribes | regulates the relationship between the branch number of the component (A) in a resin composition, and the tensile elasticity modulus of a sheet-like resin composition.

1. Extrusion Resin Composition The extrusion resin composition of the present invention (hereinafter also simply referred to as a resin composition) comprises the following ethylene / α-olefin copolymer component (A) and organic peroxide component (B). It is characterized by containing.

(1) Component (A)
Component (A) used in the present invention has the following characteristics (a1) to (a4), and (a5) and / or (a6), if necessary, ethylene / α-olefin copolymer It is a coalescence.

(A1) Density is 0.860-0.920 g / cm ³
(A2) The ratio (Mz / Mn) of Z average molecular weight (Mz) and number average molecular weight (Mn) determined by gel permeation chromatography (GPC) was 8.0 or less (a3) Shear measured at 100 ° C. rate melt viscosity at _{^{2.43 × 10s -1 (η * 1}} ) was measured at 1.2 × ¹⁰ 5 poise or (a4) 100 ℃, shear rate at 2.43 × ¹⁰ 2 ^{s -1} Melt viscosity (η ^* ₂ ) is 2.0 × 10 ⁴ poise or more

(A5) The number of branches (N) due to the comonomer in the polymer satisfies the following formula (a).
Formula (a): N ≧ −0.67 × E + 53
(However, N is the number per 1000 carbon atoms in total of the main chain and side chain measured by NMR, and E is the tensile modulus of the sheet measured according to ISO 1184-1983.)
(A6) Flow ratio (FR): ratio of I10, which is an MFR measurement value at 190 ° C. under a ₁₀ kg load, to I _2.16 , which is an MFR measurement value at 190 ° C. under a 2.16 kg load (I ₁₀ / I _2.16 ) is less than 7.0

(I) Monomer structure of component (A) The ethylene / α-olefin copolymer used in the present invention is a random copolymer of ethylene and α-olefin, the main component of which is a structural unit derived from ethylene. .
The α-olefin used as a comonomer is preferably an α-olefin having 3 to 12 carbon atoms. Specifically, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-heptene, 4-methyl-pentene-1, 4-methyl-hexene-1, 4,4-dimethylpentene- 1 etc. can be mentioned. Specific examples of such ethylene / α-olefin copolymers include ethylene / propylene copolymers, ethylene / 1-butene copolymers, ethylene / 1-hexene copolymers, ethylene / 1-octene copolymers, ethylene -4-methyl-pentene-1 copolymer etc. are mentioned. Of these, ethylene / 1-butene copolymer and ethylene / 1-hexene copolymer are preferable. Moreover, 1 type, or 2 or more types of combination may be sufficient as an alpha olefin. When combining two kinds of α-olefins to form a terpolymer, ethylene / propylene / 1-hexene terpolymer, ethylene / 1-butene / 1-hexene terpolymer, ethylene / propylene -1-octene terpolymer, ethylene / 1-butene / 1-octene terpolymer, etc. are mentioned.
As a comonomer, a small amount of a diene compound such as 1,5-hexadiene, 1,6-heptadiene, 1,7-octadiene, 1,8-nonadiene, and 1,9-decadiene may be added to the α-olefin. When these diene compounds are blended, long-chain branching is possible, so that the crystallinity of the ethylene / α-olefin copolymer is lowered, transparency, flexibility, adhesiveness, etc. are improved, and it becomes an intermolecular crosslinking agent. So the mechanical strength increases. Moreover, since the terminal group of the long chain branch is an unsaturated group, it can easily undergo a crosslinking reaction with an organic peroxide, a copolymerization reaction with an acid anhydride group-containing compound or an epoxy group-containing compound, and a graft reaction. it can.

The ethylene / α-olefin copolymer used in the present invention has an α-olefin content of 5 to 40% by weight, preferably 10 to 35% by weight, and more preferably 15 to 30% by weight. Within this range, flexibility and heat resistance are good.
Here, the content of α-olefin is a value measured by a 13C-NMR method under the following conditions.
Device: JEOL-GSX270 manufactured by JEOL
Concentration: 300 mg / 2 mL
Solvent: Orthodichlorobenzene

(Ii) Polymerization catalyst and polymerization method of component (A) The ethylene / α-olefin copolymer used in the present invention is a Ziegler catalyst, vanadium catalyst or metallocene catalyst, preferably a vanadium catalyst or metallocene catalyst, more preferably a metallocene catalyst. Can be manufactured using. Examples of the production method include a high-pressure ion polymerization method, a gas phase method, a solution method, and a slurry method.
Although it does not necessarily limit as a metallocene catalyst, The catalyst which uses a metallocene compound, such as a zirconium compound coordinated with the group which has a cyclopentadienyl skeleton, etc., and a promoter as a catalyst component is mentioned. Commercially available products include Harmolex (registered trademark) series, Kernel (registered trademark) series manufactured by Japan Polyethylene, Evolue (registered trademark) series manufactured by Prime Polymer, Exelen (registered trademark) GMH series manufactured by Sumitomo Chemical, Exelen (registered trademark) FX series may be mentioned. Examples of the vanadium catalyst include a catalyst having a soluble vanadium compound and an organic aluminum halide as catalyst components.

(Iii) Characteristics of component (A) (a1) Density The ethylene / α-olefin copolymer used in the present invention has a density of 0.860 to 0.920 g / cm ³ , preferably 0.870 to 0.8. It is 915 g / cm ³ , more preferably 0.875 to 0.910 g / cm ³ . When the density of the ethylene / α-olefin copolymer is less than 0.860 g / cm ³ , the processed sheet is blocked, and when the density exceeds 0.920 g / cm ³ , the processed sheet has too high rigidity. Thus, the handling property is lacking.

  The density of the polymer can be adjusted, for example, by appropriately adjusting the α-olefin content, the polymerization temperature, the catalyst amount, and the like. The density of the ethylene / α-olefin copolymer is measured according to JIS-K6922-2: 1997 appendix (in the case of low density polyethylene) (23 ° C.).

(A2) Ratio of Z average molecular weight (Mz) to number average molecular weight (Mn) (Mz / Mn)
The ethylene / α-olefin copolymer used in the present invention has a ratio (Mz / Mn) of Z average molecular weight (Mz) to number average molecular weight (Mn) determined by gel permeation chromatography (GPC) of 8.0. Or less, preferably 5.0 or less, more preferably 4.0 or less. Moreover, Mz / Mn is 2.0 or more, preferably 2.5 or more, more preferably 3.0 or more. However, when Mz / Mn exceeds 8.0, transparency deteriorates. In order to adjust Mz / Mn to a predetermined range, a method of selecting an appropriate catalyst system can be used.

In addition, the measurement of Mz / Mn is performed by gel permeation chromatography (GPC), and the measurement conditions are as follows.
Apparatus: Waters GPC 150C type detector: MIRAN 1A infrared spectrophotometer (measurement wavelength: 3.42 μm)
Column: Showa Denko AD806M / S 3 (column calibration was measured by Tosoh monodisperse polystyrene (0.5 mg / ml solution of each of A500, A2500, F1, F2, F4, F10, F20, F40, and F288) The logarithmic value of the elution volume and molecular weight was approximated by a quadratic equation, and the molecular weight of the sample was converted to polyethylene using the viscosity equation of polystyrene and polyethylene, where the coefficient of the viscosity equation of polystyrene is α = 0.723, log K = -3.967, polyethylene is α = 0.733, log K = -3.407.)
Measurement temperature: 140 ° C
Concentration: 20 mg / 10 mL
Injection volume: 0.2ml
Solvent: Orthodichlorobenzene Flow rate: 1.0 ml / min

  Since the Z average molecular weight (Mz) greatly contributes to the average molecular weight of the high molecular weight component, Mz / Mn is easier to confirm the presence of the high molecular weight component than Mw / Mn. The high molecular weight component is a factor that affects the transparency, and when the high molecular weight component is large, the transparency is deteriorated. Moreover, the tendency for a crosslinking efficiency to deteriorate is seen. Therefore, a smaller Mz / Mn is preferable.

(A3), (a4) Melt viscosity The ethylene / α-olefin copolymer used in the present invention must have a shear rate in a specific range measured at 100 ° C. The reason for paying attention to the shear rate measured at 100 ° C. is to estimate the influence on the product when the composition at that temperature is commercialized.
That is, the melt viscosity (η ^* ₁ ) at a shear rate of 2.43 × 10 sec ⁻¹ is 1.2 × 10 ⁵ poise or more, preferably 1.3 × 10 ⁵ poise or more, more preferably 1.4 × 10 ⁵ poise. Poise or more, more preferably 1.5 × 10 ⁵ poise or more, particularly preferably 1.6 × 10 ⁵ poise or more. The melt viscosity (η ^* ₁ ) is preferably 9.0 × 10 ⁵ poise or less, more preferably 5.0 × 10 ⁵ poise or less. If the melt viscosity (η ^* ₁ ) is within this range, the productivity at low temperature and low speed molding is good, and there is no problem in processing into products.
The melt viscosity (η ^* ₁ ) can be adjusted by the melt flow rate (MFR) or molecular weight distribution of the ethylene / α-olefin copolymer. When the value of the melt flow rate is lowered, the melt viscosity (η ^* ₁ ) tends to increase. If other properties such as molecular weight distribution are different, the magnitude relationship may be reversed. For example, preferably MFR (JIS-K6922-2: 1997 annex (190 ° C., 21.18 N load)) is 0.1. To 2.5 g / 10 min, more preferably 0.5 to 2.3 g / 10 min, still more preferably 0.7 to 2.0 g / 10 min, most preferably 0.8 to 1.5 g / 10. By setting it as minutes, the melt viscosity (η ^* ₁ ) can be easily kept within a predetermined range.

Furthermore, the ethylene / α-olefin copolymer used in the present invention has a melt viscosity (η ^* ₂ ) of 2.0 × 10 ⁴ measured at 100 ° C. at a shear rate of 2.43 × 10 ² sec ^−1. poise or more, preferably 2.1 × 10 ⁴ poise or more, more preferably 2.2 × 10 ⁴ poise or more, more preferably 2.3 × 10 ⁴ poise or more, most preferably 2.4 × 10 ⁴ poise or more is there. The melt viscosity (η ^* ₂ ) is preferably 9.0 × 10 ⁴ poise or less, more preferably 5.0 × 10 ⁴ poise or less. If the melt viscosity (η ^* ₂ ) is within this range, productivity at high speed molding at low temperatures is good, and there is no problem in processing into products.
Here, the melt viscosities (η ^* ₁ ) and (η ^* ₂ ) are measured values obtained using a capillary rheometer having a capillary with a diameter of 1.0 mm and L / D = 10.
The two kinds of shear rates are provided so that the influence on the surface of the product at the time of low speed molding and high speed molding is small, and the same product can be obtained in each molding speed region.
In the ethylene / α-olefin copolymer used in the present invention, the ratio of η ^* ₁ to η ^* ₂ (η ^* ₁ / η ^* ₂ ) is preferably 8.0 or less, more preferably 7.0. Hereinafter, it is more preferably 6.8 or less, particularly preferably 6.5 or less. The ratio of η ^* ₁ and η ^* ₂ (η ^* ₁ / η ^* ₂ ) is preferably 1.5 or more, more preferably 2.0 or more, still more preferably 3.0 or more, and particularly preferably 4.0. The above is preferable. If (η ^* ₁ / η ^* ₂ ) is in the above range, the influence on the sheet surface during low speed molding and high speed molding is small, which is preferable.

(A5) Number of branches by comonomer in the polymer (N)
In the ethylene / α-olefin copolymer used in the present invention, the number of branches (N) by the comonomer in the polymer and the tensile modulus (E) preferably satisfy the following formula (a).
Formula (a): N ≧ −0.67 × E + 53
(Where N is the number of branches per 1000 carbon atoms in total of the main chain and side chain measured by NMR, and E is the tensile modulus of the sheet measured in accordance with ISO 1184-1983.) )
Here, the number of branches (N) due to the comonomer in the polymer is, for example, E.I. W. Hansen, R.A. Blom, and O.M. M.M. It can be calculated from the C-NMR spectrum with reference to Bade, Polymer, 36, 4295 (1997).
The relationship between the number of branches of the component (A) in the resin composition and the tensile elastic modulus of the sheet-shaped resin composition is graphed as shown in FIG. The range of the formula (a) defined in the present invention is a broken line and a region above the broken line. Within this region (■ mark, ◆ mark), the balance between the rigidity of the resin composition and the crosslinking efficiency is good, and this is preferable for obtaining the solar cell encapsulant of the present invention, but below this region (▲ mark). Then, this balance deteriorates and it becomes difficult to obtain the solar cell sealing material of the present invention.

In the solar cell module, the solar cell encapsulant tends to become thinner as the solar cell element becomes thinner. In the solar cell encapsulating material having a reduced thickness, when an impact is applied from the upper or lower protective material side, the wiring is easily disconnected, so that the rigidity of the encapsulating material is required to be increased. When the rigidity is increased, the crosslinking efficiency is deteriorated. Therefore, a copolymer having a high degree of branching of the polymer chain is used to improve the fluidity of the copolymer before crosslinking and to be used as a material having excellent moldability. There is a need. In the present invention, by selecting a polymer structure in which the number of branches (N) by the comonomer of the ethylene / α-olefin copolymer satisfies the formula (a), the balance between rigidity and crosslinking efficiency is good. It can be.
The ethylene / α-olefin copolymer according to the present invention can be produced by a copolymerization reaction using a catalyst as described above, but the composition ratio of raw material monomers to be copolymerized and the type of catalyst to be used are selected. Thus, the degree of branching in the polymer chain can be easily adjusted. In order for the ethylene / α-olefin copolymer used in the present invention to satisfy the formula (a), the comonomer in the ethylene / α-olefin copolymer is selected from propylene, 1-butene, or 1-hexene. Is preferred. Moreover, it is preferable to produce using a vapor phase method or a high pressure method, and it is more preferable to select a high pressure method.
More specifically, in order to fix E and increase / decrease N, it is possible to mainly use a method of changing the carbon number of the comonomer copolymerized with ethylene. The ethylene / α-olefin copolymer is mixed by mixing so that the amount of 1-butene or 1-hexene is 60 to 80 wt% with respect to ethylene and using a metallocene catalyst to react at a polymerization temperature of 130 to 200 ° C. It is preferable to manufacture. Thereby, the number of branches N of the ethylene / α-olefin copolymer can be adjusted appropriately, and the resulting sheet has a tensile elastic modulus E of 40 MPa or less, and the ethylene / α-olefin within the range represented by the formula (a). A copolymer can be obtained.

In the present invention, the relational expression of the characteristic (a5) is preferably represented by the following expression (a ′). Further, the relational expression of the characteristic (a5) is more preferably the following expression (a ″), and particularly preferably the following expression (a ′ ″). By satisfying such conditions, the balance between the rigidity of the resin composition and the crosslinking efficiency is further improved.
Formula (a ′): −0.67 × E + 100 ≧ N ≧ −0.67 × E + 53
Formula (a ″): −0.67 × E + 80 ≧ N ≧ −0.67 × E + 53
Formula (a ′ ″): −0.67 × E + 75 ≧ N ≧ −0.67 × E + 54

(A6) Flow ratio (FR)
Ethylene · alpha-olefin copolymer used in the present invention, the _{I 10} a MFR value measured at 10kg load in the flow ratio (FR), i.e. 190 ° C., in MFR measured at 2.16kg load at 190 ° C. it is preferable ratio between certain _{I 2.16 (I 10 / I 2.16} ) is less than 7.0. The melt flow rate (MFR) is a value measured according to JIS-K7210-1999.

It is known that FR has a strong correlation with the molecular weight distribution of ethylene / α-olefin copolymer and the amount of long chain branching. In the present invention, among polymers satisfying the above conditions (a1) to (a4), the MFR measurement value (I ₁₀ ) at 190 ° C. under a 10 kg load and the MFR measurement value (I ₁₀ ) at 190 ° C. under a 2.16 kg load (I _2.16 ) and a ratio (I ₁₀ / I _2.16 ) of less than 7.0 are used. By using a copolymer having a polymer structure characterized by such long-chain branching, the balance between rigidity and crosslinking efficiency is good. On the other hand, when FR is 7.0 or more, the crosslinking efficiency at the time of crosslinking as a solar cell sealing material tends to deteriorate.
The FR of the ethylene / α-olefin copolymer used in the present invention is less than 7.0, preferably less than 6.5, and more preferably less than 6.3. However, if the FR is less than 5.0, it may be difficult to obtain sufficient rigidity as a solar cell encapsulant. The flow ratio (FR) of the characteristic (a6) is most preferably 5.0 to 6.2.

(4) Component (B)
Component (B) used in the resin composition of the present invention is an organic peroxide, and is mainly used for crosslinking component (A).
As the organic peroxide, an organic peroxide having a decomposition temperature (temperature at which the half-life is 1 hour) is 70 to 180 ° C., particularly 90 to 160 ° C. can be used. Examples of such organic peroxides include t-butyl peroxyisopropyl carbonate, t-butyl peroxy-2-ethylhexyl carbonate, t-butyl peroxyacetate, t-butyl peroxybenzoate, dicumyl peroxide, 2 , 5-dimethyl-2,5-di (t-butylperoxy) hexane, di-t-butylperoxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3, 1 , 1-di (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-di (t-butylperoxy) cyclohexane, methyl ethyl ketone peroxide, 2,5-dimethylhexyl-2,5- Diperoxybenzoate, t-butyl hydroperoxide, p-menthane hydroperoxy Id, benzoyl peroxide, p- chlorobenzoyl peroxide, t- butyl peroxy isobutyrate, hydroxyheptyl peroxide, and di cyclohexanone peroxide.

(5) Blending ratio of component (B) The blending ratio of component (B) is preferably 0.2 to 5 parts by weight, more preferably 0, when component (A) is 100 parts by weight. 0.5-3 parts by weight, more preferably 1-2 parts by weight. If the blending ratio of the component (B) is less than the above range, it will not crosslink or it will take a long time to crosslink. If it is greater than the above range, dispersion will be insufficient and the degree of crosslinking will tend to be uneven. .

(6) Hindered amine light stabilizer (C)
In the present invention, it is preferable to blend a hindered amine light stabilizer in the resin composition. The hindered amine light stabilizer captures radical species harmful to the polymer and prevents generation of new radicals. There are many types of hindered amine light stabilizers ranging from low molecular weight compounds to high molecular weight compounds, but any conventionally known compounds can be used without particular limitation.

  Low molecular weight hindered amine light stabilizers include decanedioic acid bis (2,2,6,6-tetramethyl-1 (octyloxy) -4-piperidinyl) ester, 1,1-dimethylethyl hydroperoxide and Consists of 70% by weight of a reaction product of octane (molecular weight 737) and 30% by weight of polypropylene; bis (1,2,2,6,6-pentamethyl-4-piperidyl) [[3,5-bis (1,1 -Dimethylethyl) -4-hydroxyphenyl] methyl] butyl malonate (molecular weight 685); bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate and methyl-1,2,2,6 6-pentamethyl-4-piperidyl sebacate mixture (molecular weight 509); bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate ( 481); tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate (molecular weight 791); tetrakis (1,2,2,6, 6-pentamethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate (molecular weight 847); 2,2,6,6-tetramethyl-4-piperidyl-1,2,3,4-butane Mixture of tetracarboxylate and tridecyl-1,2,3,4-butanetetracarboxylate (molecular weight 900); 1,2,2,6,6-pentamethyl-4-piperidyl-1,2,3,4-butane Examples thereof include a mixture (molecular weight 900) of tetracarboxylate and tridecyl-1,2,3,4-butanetetracarboxylate.

  As the high molecular weight hindered amine light stabilizer, poly [{6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl} {(2, 2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}] (molecular weight 2,000-3,100); succinic acid Polymer of dimethyl and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol (molecular weight 3,100 to 4,000); N, N ′, N ″, N ″ ′-tetrakis- ( 4,6-bis- (butyl- (N-methyl-2,2,6,6-tetramethylpiperidin-4-yl) amino) -triazin-2-yl) -4,7-diazadecane-1,10- Diamine (molecular weight 2,286) and above A mixture of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol; dibutylamine, 1,3,5-triazine, N, N′-bis (2,2 , 6,6-tetramethyl-4-piperidyl-1,6-hexamethylenediamine and N- (2,2,6,6-tetramethyl-4-piperidyl) butylamine polycondensate (molecular weight 2,600-3) 400) and 4-acryloyloxy-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-1,2,2,6,6-pentamethylpiperidine, 4-acryloyloxy-1-ethyl -2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-1-propyl-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy 1-butyl-2,2,6,6-tetramethylpiperidine, 4-methacryloyloxy-2,2,6,6-tetramethylpiperidine, 4-methacryloyloxy-1,2,2,6,6-pentamethyl Peridine, 4-methacryloyloxy-1-ethyl-2,2,6,6-tetramethylpiperidine, 4-methacryloyloxy-1-butyl-2,2,6,6-tetramethylpiperidine, 4-crotonoyloxy Examples include copolymers of cyclic aminovinyl compounds such as -2,2,6,6-tetramethylpiperidine, 4-crotonoyloxy-1-propyl-2,2,6,6-tetramethylpiperidine and ethylene. The above-mentioned hindered amine light stabilizers may be used alone or in combination of two or more.

  Among these, as the hindered amine light stabilizer, poly [{6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl} {(2 , 2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}] (molecular weight 2,000-3,100); Polymer of dimethyl acid and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol (molecular weight 3,100 to 4,000); N, N ′, N ″, N ″ ′-tetrakis- (4,6-Bis- (butyl- (N-methyl-2,2,6,6-tetramethylpiperidin-4-yl) amino) -triazin-2-yl) -4,7-diazadecane-1,10 -Diamine (molecular weight 2,286) A mixture of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol; dibutylamine, 1,3,5-triazine, N, N′-bis (2 , 2,6,6-Tetramethyl-4-piperidyl-1,6-hexamethylenediamine and N- (2,2,6,6-tetramethyl-4-piperidyl) butylamine polycondensate (molecular weight 2,600) ~ 3,400) Copolymers of cyclic aminovinyl compounds and ethylene are preferable, which can prevent the hindered amine light stabilizer from bleeding out over time during product use. It is preferable to use the agent having a melting point of 60 ° C. or more from the viewpoint of easy production of the composition.

In the present invention, the content of the hindered amine light stabilizer is 0.01 to 2.5 parts by weight, preferably 0.01 to 1 part by weight based on 100 parts by weight of the ethylene / α-olefin copolymer. 0 parts by weight, more preferably 0.01 to 0.5 parts by weight, still more preferably 0.01 to 0.2 parts by weight, and most preferably 0.03 to 0.1 parts by weight. When the content is 0.01 parts by weight or more, a sufficient stabilizing effect is obtained, and when the content is 2.5 parts by weight or less, the resin is discolored due to excessive addition of a hindered amine light stabilizer. In the present invention, the weight ratio (B: C) of the organic peroxide (B) to the hindered amine light stabilizer (C) is 1: 0.01 to 1:10. , Preferably 1: 0.02 to 1: 6.5. Thereby, it becomes possible to remarkably suppress yellowing of the resin.

(7) Crosslinking aid Further, a crosslinking aid can be blended in the resin composition of the present invention. The crosslinking aid is effective in promoting the crosslinking reaction and increasing the degree of crosslinking of the ethylene / α-olefin copolymer. Specific examples thereof include polyaryl compounds and poly (meth) acryloxy compounds. Saturated compounds can be exemplified.
More specifically, polyallyl compounds such as triallyl isocyanurate, triallyl cyanurate, diallyl phthalate, diallyl fumarate, diallyl maleate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, etc. Examples include poly (meth) acryloxy compounds and divinylbenzene. A crosslinking adjuvant can be mix | blended in the ratio of about 0-5 weight part with respect to 100 weight part of component (A).

(8) Ultraviolet absorber An ultraviolet absorber can be mix | blended with the resin composition of this invention. Examples of the ultraviolet absorber include various types such as benzophenone, benzotriazole, triazine, and salicylic acid ester.
Examples of benzophenone-based ultraviolet absorbers include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-2′-carboxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, and 2-hydroxy-4. -N-dodecyloxybenzophenone, 2-hydroxy-4-n-octadecyloxybenzophenone, 2-hydroxy-4-benzyloxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, 2-hydroxy-5-chlorobenzophenone 2,2-dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, etc. To mention Can.

The benzotriazole ultraviolet absorber is a hydroxyphenyl-substituted benzotriazole compound, for example, 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-5-t-butylphenyl) Benzotriazole, 2- (2-hydroxy-3,5-dimethylphenyl) benzotriazole, 2- (2-methyl-4-hydroxyphenyl) benzotriazole, 2- (2-hydroxy-3-methyl-5-t- Butylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-t-amylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-t-butylphenyl) benzotriazole, and the like. Can be mentioned. Examples of triazine ultraviolet absorbers include 2- [4,6-bis (2,4-dimethylphenyl) -1,3,5-triazin-2-yl] -5- (octyloxy) phenol, 2- ( And 4,6-diphenyl-1,3,5-triazin-2-yl) -5- (hexyloxy) phenol. Examples of salicylic acid esters include phenyl salicylate and p-octylphenyl salicylate.
These ultraviolet absorbers are blended in an amount of 0 to 2.0 parts by weight, preferably 0.05 to 2.0 parts by weight, more preferably 0.1 to 1. part by weight based on 100 parts by weight of the ethylene / α-olefin copolymer. 0 parts by weight, more preferably 0.1 to 0.5 parts by weight, and most preferably 0.2 to 0.4 parts by weight.

(9) Other additive components In the resin composition of the present invention, other optional additional components can be blended within a range that does not significantly impair the object of the present invention. As such optional components, antioxidants, crystal nucleating agents, clearing agents, lubricants, colorants, dispersants, fillers, fluorescent whitening agents, UV absorbers used in ordinary polyolefin resin materials, A light stabilizer etc. can be mentioned.
Further, in order to impart flexibility and the like to the resin composition of the present invention, a crystalline ethylene / α-olefin copolymer polymerized by a Ziegler-based or metallocene-based catalyst within a range not impairing the object of the present invention. And / or rubber compounds such as EBR, EPR and other ethylene / α-olefin elastomers or SEBS, styrene elastomers such as hydrogenated styrene block copolymers, and the like in an amount of 3 to 75 weights per 100 parts by weight of the resin composition. Partial blending can also be performed. Furthermore, in order to give melt tension etc., 3-75 weight part of high pressure process low density polyethylene can also be mix | blended. Furthermore, 3 to 75 parts by weight of high-pressure low-density polyethylene and ethylene / vinyl acetate copolymer can be blended in order to impart melt tension and the like.

  The resin composition for extrusion molding of the present invention can be used in various applications and is not limited by the application, but is particularly suitable for outdoor use because of its excellent heat resistance, transparency, flexibility, etc. Suitable for solar cell encapsulant, water shielding sheet, tarpaulin and the like.

2. Solar cell encapsulant The solar cell encapsulant of the present invention (hereinafter also simply referred to as encapsulant) uses the above resin composition, and is used after being pelletized or formed into a sheet.

When using the resin composition of this invention for the sealing material for solar cells, in order to improve the adhesive force with an upper protection material or a solar cell element, the resin composition may further contain the silane coupling agent. .
Examples of the silane coupling agent include γ-chloropropyltrimethoxysilane; vinyltrichlorosilane; vinyltriethoxysilane; vinyltrimethoxysilane; vinyl-tris- (β-methoxyethoxy) silane; γ-methacryloxypropyltrimethoxysilane. Β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane; γ-glycidoxypropyltrimethoxysilane; vinyltriacetoxysilane; γ-mercaptopropyltrimethoxysilane; γ-aminopropyltrimethoxysilane; N-β -(Aminoethyl) -γ-aminopropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane and the like can be mentioned. Vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, and 3-acryloxypropyltrimethoxysilane are preferable.
These silane coupling agents are used in an amount of 0 to 5 parts by weight, preferably 0.01 to 5 parts by weight, more preferably 0.01 to 2 parts by weight, based on 100 parts by weight of the ethylene / α-olefin copolymer. More preferably, it is used at 0.05 to 1 part by weight.

The solar cell encapsulant of the present invention may be used as a pellet, but is usually used after being formed into a sheet having a thickness of about 0.1 to 1 mm. If the thickness is less than 0.1 mm, the strength is small and the adhesion is insufficient. If the thickness is more than 1 mm, the transparency may be lowered, which may be a problem. A preferred thickness is 0.1 to 0.8 mm.
The sheet-like solar cell encapsulant can be produced by a known sheet molding method such as calendar molding using a calendar molding machine. Calendar molding is a method in which a resin material is rolled while being melted with a heating roll, and is formed into a sheet through several rolls.
In calendar molding, a cross-linking agent is added to the ethylene / α-olefin copolymer and, if necessary, a hindered amine light stabilizer, a cross-linking aid, a silane coupling agent, an ultraviolet absorber, and an antioxidant. Then, additives such as a light stabilizer are previously dry blended and melt-kneaded, and then the kneaded product is conveyed by a conveyor and supplied to a kneading roll. In this dry blending, some or all of the additives can be used in the form of a masterbatch. In addition, a resin composition obtained by melt-mixing a part or all of an additive to an amorphous α-olefin copolymer in advance using a single screw extruder, a twin screw extruder, a Banbury mixer, a kneader, or the like. It can also be used.
The kneaded material kneaded with the kneading roll is conveyed by a conveyor, rolled with four calender rolls heated to 80 to 130 ° C., and the rolled sheet is taken out with a take-off roll. Thereafter, the rolled sheet is cooled by a cooling roll, and the cooled sheet may be wound by a winder.

3. Solar cell module In this invention, a solar cell module can be manufactured by sealing a solar cell element using the said solar cell sealing material, and also fixing with a protective material.

  As the solar cell module of the present invention, various types can be exemplified. For example, the upper transparent protective material / encapsulant / solar cell element / encapsulant / lower protective material sandwiched between the solar cell elements from both sides, formed on the inner peripheral surface of the lower substrate protective material A solar cell element formed on the inner peripheral surface of the upper transparent protective material, for example, a fluororesin-based transparent protective material. The thing of the structure which forms a sealing material and a lower protective material on what created the amorphous solar cell element by sputtering etc. can be mentioned.

  The solar cell element is not particularly limited, and is based on silicon such as single crystal silicon, polycrystalline silicon, amorphous silicon, III-V group or II-VI group such as gallium-arsenic, copper-indium-selenium, cadmium-tellurium. Various solar cell elements such as compound semiconductors can be used.

Examples of the upper protective material constituting the solar cell module include glass, acrylic resin, polycarbonate, polyester, and fluorine-containing resin. The lower protective material is a single or multilayer sheet such as metal or various thermoplastic resin films, for example, metals such as tin, aluminum, and stainless steel, inorganic materials such as glass, polyester, inorganic vapor deposition polyester, fluorine-containing resin And a single-layer or multilayer protective material such as polyolefin. Such an upper and / or lower protective material can be subjected to a primer treatment in order to enhance the adhesion to the sealing material.
In manufacturing the solar cell module, the sheet of the sealing material of the present invention is prepared in advance, and the above-described method is performed by pressure bonding at a temperature at which the resin composition of the sealing material melts, for example, 150 to 200 ° C. A module having a simple structure can be formed.

On the other hand, when the solar cell module is manufactured, the sealing material is temporarily applied to the solar cell element or the protective material at a temperature at which the organic peroxide is not substantially decomposed and the sealing material of the present invention is melted. Adhesion is then carried out to raise the temperature, and sufficient adhesion and crosslinking of the ethylene / α-olefin copolymer can be carried out. In this case, the gel in the encapsulant layer is used in order to obtain a solar cell module with good heat resistance having a melting point (DSC method) of the encapsulant layer of 85 ° C. or higher and a storage elastic modulus of 150 ° C. of 10 ³ Pa or higher. Fraction (1 g of sample is immersed in 100 ml of xylene, heated at 110 ° C. for 24 hours, then filtered through a 20 mesh wire net and the mass fraction of unmelted portion is measured) is 50 to 98%, preferably about 70 to 95% It is better to crosslink so that

  In Patent Document 2, 100 parts by weight of an amorphous or low crystalline ethylene / butene copolymer is added to 2,5-dimethyl-2,5-di (t-butylperoxy) hexane as an organic peroxide. A mixture of 1.5 parts by weight and 2 parts by weight of triallyl isocyanurate as a crosslinking aid was produced using a profile extruder at a processing temperature of 100 ° C. and a thickness of 0.5 mm (Example 3). ). However, when such a composition is selected, sufficient productivity cannot be obtained because the processing temperature is low.

  In the sealing operation of the solar cell element, after covering the solar cell element with the sealing material of the present invention, the solar cell element is temporarily bonded by heating to a temperature at which the organic peroxide is not decomposed for several minutes to 10 minutes, In addition, there is a method in which the organic peroxide is decomposed in the oven at a high temperature of about 150 to 200 ° C. for 5 to 30 minutes to be bonded.

4). Water-impervious sheet The water-impervious sheet of the present invention is used at the site of laying a waste disposal site and completely covers the surface of the waste.

The water shielding sheet of the present invention is not particularly limited by its production method, and is produced by an inflation method, a T-die method or the like. That is, with the inflation method, a thick and wide sheet can be formed at high speed, which is excellent in economic efficiency. Further, the thickness of the water-impervious sheet is generally 200 μm or more, particularly preferably 300 μm or more, and as a super flexible grade, the Young's modulus is adjusted to about 200 N / mm ² or less, more preferably 100 N / mm ² or less. It is desirable.

  For the purpose of improving the weather resistance, the water shielding sheet of the present invention preferably contains 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight, of carbon black with respect to 100 parts by weight of the resin component. . The carbon black is preferably furnace black and has an average particle diameter of 1 to 200 mμ, preferably 3 to 100 mμ, and more preferably 5 to 50 mμ. If the particle size and blending amount of the carbon black are outside the above ranges, the weather resistance effect may be reduced, or the performance of the water shielding sheet may be hindered.

When handling the water shielding sheet of the present invention, for example, it is carried in a wound state to the laying site of the disposal site, the sheet is expanded in the disposal site, and a large number of the water shielding sheets are covered so as to completely cover the surface of the disposal site. After laying, the water shielding sheets are joined to each other.
Any known technique can be used as the bonding method. Examples include bonding with adhesives, hot plate bonding using adhesive sealing material and high heat, hot air welding method in which sheets are melted and bonded together, welding type welding method using a welding rod, etc. A hot air welding method and a welding-type welding method are preferred. Moreover, when joining by a welding method, a water-impervious sheet | seat is piled up mutually, and the resin which consists of the same material as a water-impervious sheet is utilized as a welding rod in the overlapping part, and it fuse | melts by heat and integrates. According to this method, since a different material solvent or adhesive that causes deterioration of the joint portion is not used, the fused portion has exactly the same strength, water shielding and durability as the water shielding sheet. The water shielding sheet of the present invention is advantageous because it can be easily and completely joined by heat.

  The water-impervious sheet of the present invention can be used as it is by blending the above-described resin component or resin composition with carbon black, but natural rubber, various synthetic rubbers, and thermoplastic elastomers within a range not departing from the performance. Or tackifiers, crosslinking agents, and various fillers such as calcium carbonate, talc, silica, metal fibers, carbon fibers, antioxidants, UV inhibitors, flame retardants, colorants, crosslinking agents, etc. You may mix | blend.

5. Tarpaulin The tarpaulin of the present invention comprises a fiber knitted fabric as a base fabric, and a layer of the ethylene copolymer composition is laminated on at least one side, preferably both sides, as a signboard, tent, etc. It is what is used. Tents are used not only for exhibitions and various events, but also as covers for building material storage and agricultural equipment storage.

  As a method for laminating the ethylene copolymer composition on the base fabric, known methods such as a calendering method, an extrusion laminating method, a dry laminating method, and an impregnation method can be used. Among these, a calendar processing method is preferable.

Specifically, the tarpaulin of the present invention is prepared by molding the resin composition prepared above into a sheet shape by a calender roll and melt-laminating it on the base fabric, or using the adhesive between the molded sheet and the base fabric. Manufactured by dry lamination and lamination.
In this case, the temperature of the resin composition in the melt lamination on one side or both sides of the base fabric is usually about 100 to 160 ° C., for example, in the case of calendering, and the thickness of the resin composition layer The thickness is about 100 to 1000 μm per surface.

Further, as the textile fabric of the base fabric, those conventionally used for this type of base fabric may be used. Specifically, for example, synthetic fibers such as polyester fibers, polyamide fibers, polyolefin fibers, polyacryl fibers, etc. Or, woven fabrics such as plain weaves, twill weaves, satin weaves, and knitted fabrics such as natural fibers such as cotton and hemp.
Furthermore, the thickness of the fiber is about 200 to 1000 denier. For example, in the case of plain weaving, the number of driving is about (10-30) × (15-35) / inch. These fiber knitted fabrics generally have a width and length of about 0.5 to 5 m and a thickness of about 0.2 to 1 mm.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The evaluation methods and resins used in the examples and comparative examples are as follows.

1. Evaluation method of resin physical properties (1) Melt flow rate (MFR): MFR of ethylene / α-olefin copolymer is measured according to JIS-K6922-2: 1997 appendix (190 ° C., 21.18 N load). did.
(2) Density: As described above, the density of the ethylene / α-olefin copolymer was measured according to JIS-K6922-2: 1997 appendix (23 ° C., in the case of low density polyethylene).
(3) Mz / Mn: Measured by GPC as described above.
(4) Melt viscosity: In accordance with JIS-K-7199-1999, using Capillograph 1-B manufactured by Toyo Seiki Seisakusho, using a capillary with set temperature: 100 ° C., D = 1 mm, L / D = 10, melt viscosity at a shear rate of _{^{2.43 × 10sec -1 (η * 1}} ), were measured melt viscosity at a shear rate of ^{2.43 × 10 2 sec -1 (η} * 2).
(5) Number of branches: The number of branches (N) in the polymer was measured by NMR under the following conditions, and the amount of comonomer was determined by the number of main chains and side chains per 1000 carbons in total.
Equipment: Bruker BioSpin Corporation AVANCE III cryo-400MHz
Solvent: o-dichlorobenzene / deuterated bromobenzene = 8/2 mixed solution <sample amount>
460mg / 2.3ml
<C-NMR>
・ H decouple, NOE available ・ Number of integration: 256scan
・ Flip angle: 90 °
・ Pulse interval 20 seconds ・ AQ (acquisition time) = 5.45 s D1 (waiting time) = 14.55 s
(6) FR: Based on JIS-K7210-1999, MFR (I ₁₀ ) measured under conditions of 190 ° C. and 10 kg load, and MFR (I 2.) measured under conditions of 190 ° C. and 2.16 kg load _{. 16} ) and the ratio (I ₁₀ / I _2.16 ) was calculated as FR.

2. Evaluation Method of Extruded Product (Sheet) (1) Calendar Formability After the resin composition was melt-kneaded, it was supplied to a calender molding machine and extruded into a sheet with a calender roll. The temperature of the calendar roll was 100 ° C., and the rotation speed was 10 m / min. At that time, the case where molding was possible with a calendar roll was evaluated as good (o), and the case where molding was impossible was evaluated as poor (x).

(2) HAZE
It measured based on JIS-K7136-2000 using the press sheet of thickness 0.7mm. The press sheet piece was set in a glass cell containing special liquid paraffin made by Kanto Chemical Co., Ltd. and measured. The press sheet was stored in a hot press machine at 160 ° C. for 30 minutes, and prepared by crosslinking. The smaller the HAZE value, the better.

(3) Light transmittance It measured based on JIS-K7361-1-1997 using the press sheet of thickness 0.7mm. The press sheet piece was set in a glass cell containing special liquid paraffin made by Kanto Chemical Co., Ltd. and measured. The press sheet was stored in a hot press machine at 160 ° C. for 30 minutes, and prepared by crosslinking.
The light transmittance is 80% or more, preferably 85% or more, and more preferably 90% or more.

(4) Tensile elasticity modulus It measured based on ISO1184-1983 using the press sheet of thickness 0.7mm bridge | crosslinked at 160 degreeC for 30 minutes. The tensile elastic modulus was determined when the tensile rate was 1 mm / min, the test piece width was 10 mm, the distance between grips was 100 mm, and the elongation was 1%. It shows that it is excellent in the softness, so that this value is small.
(5) Heat resistance It evaluated by the gel fraction of the sheet | seat bridge | crosslinked at 160 degreeC and the sheet | seat bridge | crosslinked at 150 degreeC for 30 minutes. It can be evaluated that the higher the gel fraction, the more the crosslinking proceeds and the higher the heat resistance. A gel fraction having a gel fraction of 70 wt% or more was designated as a heat resistance evaluation “◯”. As for the gel fraction, about 1 g of the sheet is cut out and weighed accurately, immersed in 100 cc of xylene, treated at 110 ° C. for 24 hours, the residue after filtration is dried and weighed, and divided by the weight before treatment. Calculate the gel fraction.

3. Raw Material Used (1) Component (A): Ethylene / α-Olefin Copolymer Ethylene and 1-hexene copolymer (PE-1) polymerized in the following <Production Example 1>, polymerized in <Production Example 2> Copolymer of ethylene and 1-butene (PE-2), copolymer of ethylene and 1-hexene polymerized in <Production Examples 3 and 4> (PE-3) (PE-4), and <Production Example 5 >, Ethylene, propylene and 1-hexene copolymer (PE-9), and commercially available ethylene / α-olefin copolymer (PE-5) (PE-6) (PE-7) (PE- 8) was used. The physical properties are shown in Table 1.
(2) Organic peroxide: 2,5-dimethyl-2,5-di (t-butylperoxy) hexane (manufactured by Arkema Yoshitomi, Luperox 101)
(3) Hindered amine light stabilizer: polymer of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol (manufactured by BASF, TINUVIN 622LD)
(4) UV absorber: 2-hydroxy-4-n-octoxybenzophenone (manufactured by Sun Chemical Co., Ltd., CYTEC UV531)

<Production Example 1>
(I) Preparation of catalyst A catalyst for producing a copolymer of ethylene and 1-hexene was prepared by the method described in JP-T-7-508545. That is, to the complex dimethylsilylene bis (4,5,6,7-tetrahydroindenyl) hafnium dimethyl 2.0 mmol, tripentafluorophenyl boron is added in an equimolar amount to the complex, and diluted to 10 liters with toluene. A catalyst solution was prepared.
(Ii) Polymerization Using a stirred autoclave-type continuous reactor having an internal volume of 1.5 liters, maintaining the pressure in the reactor at 130 MPa, a mixture of ethylene and 1-hexene has a composition of 1-hexene of 72% by weight. The raw material gas was continuously supplied at a rate of 40 kg / hour. The catalyst solution was continuously supplied, and the supply amount was adjusted so that the polymerization temperature was maintained at 114 ° C. The amount of polymer produced per hour was about 1.5 kg. After completion of the reaction, an ethylene / 1-hexene copolymer having a 1-hexene content of 24% by weight, an MFR of 1.0 g / 10 min, a density of 0.880 g / cm ³ , and Mz / Mn of 3.7 ( PE-1) was obtained.
Further, after 3 minutes preheat the PE-1 at ^{160 ℃ -0kg / cm 3, 160} ℃ 5 minutes pressurized with 100 kg / cm ^3, then the conditions of 100 kg / cm ³ to a cooling press set to 30 ° C. Then, a press sheet having a thickness of 0.7 mm was obtained by cooling for 10 minutes. The tensile elastic modulus was measured according to ISO 1184-1983, and as a result, it was 17 MPa.
The characteristics of this ethylene / 1-hexene copolymer (PE-1) are shown in Table 1.

<Production Example 2>
Polymerization was carried out by changing the monomer composition and polymerization temperature during polymerization in Production Example 1 so that the composition, density, and melt viscosity shown in Table 1 were obtained. After completion of the reaction, an ethylene / 1-butene copolymer having 1-butene content = 35 wt%, MFR = 1.0 g / 10 min, density = 0.870 g / cm ³ , and Mz / Mn = 3.5 ( PE-2) was obtained. As a result of measuring the tensile modulus in the same manner as in Production Example 1, it was 8 MPa. The characteristics of this ethylene / 1-butene copolymer (PE-2) are shown in Table 1.

<Production Example 3>
In Production Example 1, polymerization was carried out by the same production method as in Production Example 1 except that the composition of 1-hexene at the time of polymerization was changed to 72% by weight and the polymerization temperature was changed to 122 ° C. The polymer production per hour was about 2.1 kg. After completion of the reaction, an ethylene / 1-hexene copolymer having a 1-hexene content = 24% by weight, MFR = 2.2 g / 10 minutes, density = 0.880 g / cm ³ , and Mz / Mn = 3.7 ( PE-3) was obtained. As a result of measuring the tensile modulus in the same manner as in Production Example 1, it was 17 MPa. The characteristics of this ethylene / 1-hexene copolymer (PE-3) are shown in Table 1.

<Production Example 4>
In Production Example 1, polymerization was carried out by the same production method as in Production Example 1 except that the composition of 1-hexene at the time of polymerization was changed to 75% by weight and the polymerization temperature was changed to 150 ° C. The polymer production per hour was about 4.3 kg. After completion of the reaction, an ethylene / 1-hexene copolymer (PE-) having 1-hexene content = 24% by weight, MFR = 35 g / 10 minutes, density = 0.880 g / cm ³ , and Mz / Mn = 3.7 4) was obtained. As a result of measuring the tensile modulus in the same manner as in Production Example 1, it was 34 MPa. The characteristics of this ethylene / 1-hexene copolymer (PE-4) are shown in Table 1.

<Production Example 5>
Polymerization was carried out by changing the monomer composition and polymerization temperature during polymerization in Production Example 1 so that the composition, density, and melt viscosity shown in Table 1 were obtained. After completion of the reaction, propylene content = 14.4 wt%, 1-hexene content = 11.9 wt%, MFR = 1.0 g / 10 min, density = 0.870 g / cm ³ , Mz / Mn = 3. 5, an ethylene / propylene / 1-hexene copolymer (PE-9) was obtained. As a result of measuring the tensile modulus in the same manner as in Production Example 1, it was 8 MPa. The characteristics of this ethylene / propylene / 1-hexene copolymer (PE-9) are shown in Table 1.

Example 1
2,5-dimethyl-2,5-di (t-butylperoxy) hexane (Arkema Yoshitomi Co., Ltd.) as an organic peroxide with respect to 100 parts by weight of a copolymer of ethylene and 1-hexene (PE-1) Manufactured by Lupelox 101) and a polymer of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol (BASF) as a hindered amine light stabilizer. 0.05% by weight of TINUVIN 622LD). After melt-kneading the resin composition with a Banbury mixer, the resin composition was supplied to a calender molding machine and extruded into a sheet with a calender roll. The temperature of the calendar roll was 100 ° C., and the rotation speed was 10 m / min.
The resulting sheets, at the 160 ℃ -0kg / cm ² conditions, after 3 minutes preheat, 160 ℃ -100kg / cm (30 minutes press molding at 160 ° C.) 27 minutes pressurization at ² conditions, and then, A sheet having a thickness of 0.7 mm was produced by cooling for 10 minutes in a cooling press set to 30 ° C. under a pressure of 100 kg / cm ² . Calender moldability, sheet HAZE, light transmittance, tensile modulus, and heat resistance were measured and evaluated.
Separately for evaluation of heat resistance, under the condition of 150 ℃ -0kg / cm ^2, after 3 minutes preheat, and 27 minutes pressurization at conditions of 150 ℃ -100kg / cm2 (150 ℃ for 30 minutes press molding), Then, the sheet | seat of thickness 0.7mm was prepared by cooling for 10 minutes on the conditions of the pressurization of 100 kg / cm < ² > to the cooling press set to 30 degreeC. The evaluation results are shown in Table 2.

(Example 2)
In Example 1, a sheet was prepared in the same manner except that PE-2 was used instead of PE-1. Calender moldability, sheet HAZE, light transmittance, tensile modulus, and heat resistance were measured and evaluated. The evaluation results are shown in Table 2.

(Example 3)
In Example 1, a sheet was prepared in the same manner except that PE-3 was used instead of PE-1. Calender moldability, sheet HAZE, light transmittance, tensile modulus, and heat resistance were measured and evaluated. The evaluation results are shown in Table 2.

Example 4
In Example 1, a sheet was prepared in the same manner as in Example 1 except that 0.3 part of 2-hydroxy-4-n-octoxybenzophenone (CYTEC UV531 manufactured by Sun Chemical Co., Ltd.) was further added as an ultraviolet absorber. did. Calender moldability, sheet HAZE, tensile elastic modulus, heat resistance, and adhesiveness were measured and evaluated. The evaluation results are shown in Table 2.

(Example 5)
In Example 1, a sheet was prepared in the same manner except that PE-9 was used instead of PE-1. Calender moldability, sheet HAZE, light transmittance, tensile modulus, and heat resistance were measured and evaluated. The evaluation results are shown in Table 2.

(Comparative Example 1)
A sheet was prepared in the same manner as in Example 1 except that no organic peroxide was used. Calender moldability, sheet HAZE, tensile elastic modulus, heat resistance, and adhesiveness were measured and evaluated. The evaluation results are shown in Table 2.

(Comparative Example 2)
In Example 1, calendering similar to that in Example 1 was attempted except that PE-4 (ethylene / 1-hexene copolymer) for comparison was used instead of PE-1. However, the melt tension was insufficient and calendar molding could not be performed.

(Comparative Example 3)
A calender molding similar to that in Example 1 was attempted except that PE-5 (ethylene / 1-butene copolymer, Takumer A4085S manufactured by Mitsui Chemicals, Inc.) was used instead of PE-1. However, the melt tension was insufficient and calendar molding could not be performed.

(Comparative Example 4)
A sheet was prepared in the same manner as in Example 1 except that PE-6 (ethylene / 1-octene copolymer, Dow Chemical Engage 8100) was used instead of PE-1. Calender moldability, sheet HAZE, light transmittance, tensile modulus, and heat resistance were measured and evaluated. The evaluation results are shown in Table 2. As a result, the crosslinking efficiency was poor and the heat resistance was poor.

(Comparative Examples 5 and 6)
Instead of PE-1, PE-7 (ethylene / 1-octene copolymer, Dow Chemical Co. Engage 8200) or PE-8 (ethylene / 1-octene copolymer, Dow Chemical Co. Engage 8400) ) Was used, and the same calendar molding as in Example 1 was attempted. However, the melt tension was insufficient and calendar molding could not be performed.

"Evaluation"
As a result, as is apparent from Table 2, in Examples 1 to 5, since the resin composition of the present invention was used, it was possible to perform extrusion molding (calender molding), and the obtained sheet had HAZE. Small, high light transmittance, excellent balance of heat resistance, rigidity and crosslinking efficiency.
On the other hand, in Comparative Example 1, unlike the present invention, since no organic peroxide was used, heat resistance at 150 ° C. and 160 ° C. was not obtained. In Comparative Examples 2, 3, 5, and 6, since a resin composition containing an ethylene / α-olefin copolymer whose melt viscosity deviated from the present invention was used, calendar molding could not be performed. In Comparative Example 4, since the resin composition containing the ethylene / 1-octene copolymer in which the formula (a) and FR deviate from the present invention was used, the obtained sheet had poor crosslinking efficiency and poor heat resistance. became.

  The resin composition for extrusion molding of the present invention is used for the production of a solar cell module as a solar cell encapsulant that requires transparency, flexibility, rigidity and balance of crosslinking efficiency, weather resistance, and the like. In addition, it has good calendar moldability, excellent flexibility, weather resistance, etc., as a water shielding sheet that completely covers the surface of the disposal site at the waste disposal site, and further because the resin composition is transparent It can be used as a tarpaulin (signboard) that makes the most of its colors and a tent that requires durability.

Claims (13)

An extrusion molding resin composition comprising the following component (A) and component (B).
Component (A): ethylene / α-olefin copolymer (a1) having the following properties (a1) to (a5): Density of 0.860 to 0.920 g / cm ³
(A2) The ratio (Mz / Mn) of Z average molecular weight (Mz) and number average molecular weight (Mn) determined by gel permeation chromatography (GPC) was 8.0 or less (a3) Shear measured at 100 ° C. rate melt viscosity at _{^{2.43 × 10s -1 (η * 1}} ) was measured at 1.2 × ¹⁰ 5 poise or (a4) 100 ℃, shear rate at 2.43 × ¹⁰ 2 ^{s -1} The melt viscosity (η ^* ₂ ) is 2.0 × 10 ⁴ poise or more (a5) The number of branches (N) due to the comonomer in the polymer satisfies the following formula (a).
Formula (a): N ≧ −0.67 × E + 53
(Where N is the number of branches per 1000 carbon atoms in total of the main chain and side chain measured by NMR, and E is the tensile modulus of the sheet measured in accordance with ISO 1184-1983.) )
Component (B): Organic peroxide (A5) The resin composition for extrusion molding according to claim 1, wherein the number of branches (N) due to the comonomer in the polymer satisfies the following formula (a ′).
Formula (a ′): −0.67 × E + 100 ≧ N ≧ −0.67 × E + 53
(Where N is the number of branches per 1000 carbon atoms in total of the main chain and side chain measured by NMR, and E is the tensile modulus of the sheet measured in accordance with ISO 1184-1983.) ) (A5) The resin composition for extrusion molding according to claim 1 or 2, wherein the number of branches (N) due to the comonomer in the polymer satisfies the following formula (a '').
Formula (a ″): −0.67 × E + 80 ≧ N ≧ −0.67 × E + 53
(Where N is the number of branches per 1000 carbon atoms in total of the main chain and side chain measured by NMR, and E is the tensile modulus of the sheet measured in accordance with ISO 1184-1983.) ) An extrusion molding resin composition comprising the following component (A) and component (B).
Component (A): ethylene / α-olefin copolymer (a1) having the following characteristics (a1) to (a4) and (a6): density is 0.860 to 0.920 g / cm ³
(A2) The ratio (Mz / Mn) of Z average molecular weight (Mz) and number average molecular weight (Mn) determined by gel permeation chromatography (GPC) was 8.0 or less (a3) Shear measured at 100 ° C. rate melt viscosity at _{^{2.43 × 10s -1 (η * 1}} ) was measured at 1.2 × ¹⁰ 5 poise or (a4) 100 ℃, shear rate at 2.43 × ¹⁰ 2 ^{s -1} Melt viscosity (η ^* ₂ ) is 2.0 × 10 ⁴ poise or more (a6) Flow ratio (FR): I10 which is MFR measured value at ₁₀ ° C. load at 190 ° C. and 2.16 kg load at 190 ° C. Ratio (I ₁₀ / I _2.16 ) with I _2.16 which is MFR measurement value is less than 7.0 Component (B): Organic peroxide   The resin composition for extrusion molding according to claim 4, wherein the flow ratio (FR) of the characteristic (a6) is 5.0 to 6.2.   The resin composition for extrusion molding according to any one of claims 1 to 5, wherein the content of the component (B) is 0.2 to 5 parts by weight with respect to 100 parts by weight of the component (A). object. The resin composition for extrusion molding according to any one of claims 1 to 6, further comprising the following component (C): Component (C): hindered amine light stabilizer   The component (A) is an ethylene / propylene copolymer, ethylene / 1-butene, or ethylene / 1-hexene copolymer, and the resin for extrusion molding according to any one of claims 1 to 7 Composition.   The resin composition for extrusion molding according to any one of claims 1 to 7, wherein the component (A) is an ethylene / propylene / 1-hexene terpolymer.   The solar cell sealing material which consists of a resin composition for extrusion molding in any one of Claims 1-9.   The solar cell module using the solar cell sealing material of Claim 10.   A water shielding sheet obtained by extruding the resin composition for extrusion molding according to any one of claims 1 to 9 into a sheet shape.   A tarpaulin formed by laminating at least one surface of a base fabric using the extrusion molding resin composition according to any one of claims 1 to 9.

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