Water barrier sheet and method for producing water barrier sheet

Abstract

To provide a water barrier sheet which is excellent in mechanical characteristics such as environmental characteristics and tensile strength, and a method for producing the same.SOLUTION: A water barrier sheet is derived from an olefin resin composition containing a first polyolefin resin containing a petroleum-derived ethylene unit as a component (A), and a second polyolefin resin containing a plant-derived ethylene unit as a component (B), or a water barrier sheet is derived from an olefin resin composition containing no component (A) and containing the component (B) alone, wherein a biomass degree of the olefin resin composition according to ASTM D 6866 is set to be a value within the range of more than 40% to 100%, and an average tensile elongation rate in a length direction and a width direction according to JIS K 6251:2017 is set to be within the range of 650 to 1,200%.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a waterproof sheet and a method for manufacturing the waterproof sheet. More specifically, the present invention relates to a waterproof sheet (sometimes referred to as a civil engineering sheet, etc.) that has excellent environmental properties (such as reduced CO2 emissions) as well as excellent mechanical properties such as tensile elongation (conformity) and bending resistance, and to a method for manufacturing such a waterproof sheet. [Background technology]

[0002] Conventionally, in the development land or reservoir of a waste disposal site (including an industrial waste disposal site, a general waste disposal site, etc.), or in the development site, etc., a predetermined waterproofing construction is carried out to prevent leachate (sewage) from the waste due to rainfall or water sprinkling from migrating into the soil outside the disposal site. In such a waste disposal site, the waste is generally stored after the waterproofing construction. Furthermore, on the roofs of buildings and houses, in order to prevent rainwater from seeping in and causing adverse effects on indoor equipment due to water leakage, a specified waterproofing construction is carried out. Waterproof sheets for such waterproof construction must have high elongation and be resistant to damage even when the installation surface is uneven or the ground subsides, but they must also be resistant to impacts and have high bending resilience.

[0003] For example, because of its excellent thermal adhesion and tensile strength, and its relatively good ability to conform to the shape of the substrate, a sheet has been proposed that is molded using a material that uses a specific high-pressure low-density polyethylene and / or low-pressure linear low-density polyethylene as a base, to which a specific low-pressure linear very low-density polyethylene and an ethylene-vinyl acetate copolymer have been added (see, for example, Patent Document 1). More specifically, for 100 parts by weight of (A) high-pressure low-density polyethylene or / and low-pressure linear low-density polyethylene having a melt flow rate of 0.1 to 10 g / 10 min (190° C.), (B) a density of 0.890 to 0.914 g / cm 3The waterproof sheet is obtained by blending 2 to 50 parts by weight of the linear ultra-low density polyethylene and (C) 1 to 30 parts by weight of an ethylene-vinyl acetate copolymer having a melt flow rate of 0.8 to 40 g / 10 min (190°C) and containing 10 to 40% by weight of vinyl acetate units.

[0004] Also, a polyolefin-based waterproof sheet for civil engineering use has been proposed, which contains 1 to 20% by weight of an inorganic filler in a specific ethylene-α-olefin copolymer (see, for example, Patent Document 2). More specifically, it is a copolymer of (a) ethylene and an α-olefin having 3 to 12 carbon atoms, polymerized using a metallocene catalyst, and (b) has a density of 0.86 g / cm 3 ~0.88g / cm 3 (c) a melt index of 0.5 to 5 g / min, and (d) a ratio of weight average molecular weight (Mw) to number average molecular weight (Mn) of 1.5 to 5, and the polyolefin-based waterproof sheet for civil engineering use is formed by incorporating 1 to 20 weight % of inorganic filler having an average particle size of 1 to 20 μm into an ethylene-α-olefin copolymer.

[0005] Furthermore, a synthetic resin sheet for civil engineering has been proposed, which contains a predetermined amount of barium sulfate and one or more selected from other inorganic compounds and metal powders, limits the 1% secant elastic modulus of the sheet, and contains a predetermined amount of an ethylene-α-olefin copolymer whose density, melt flow rate, and ratio of weight average molecular weight (Mw) to number average molecular weight (Mn) are limited (see, for example, Patent Document 3). More specifically, the present invention relates to a synthetic resin sheet for civil engineering use, which contains 15 to 50% by weight of barium sulfate and one or more selected from other inorganic compounds and metal powders in a weight ratio of (a) below, and satisfies the requirement of (b) below, in which the synthetic resin is obtained by polymerization using a metallocene catalyst, and is (a) a copolymer of ethylene and an α-olefin having 3 to 12 carbon atoms, and (b) has a density of 0.86 to 0.94 g / cm. 3and (c) a melt flow rate (MFR) of 0.5 to 5 g / 10 min., and (d) a ratio (Mw / Mn) of weight average molecular weight (Mw) to number average molecular weight (Mn) of 1.5 to 5. The synthetic resin sheet for civil engineering contains 1 to 99% by weight of an ethylene-α-olefin copolymer. (a) Barium sulfate: one or more selected from other inorganic compounds and metal powders = 100:0 to 50:50 (b) The 1% secant elastic modulus of the sheet is 30 to 200 MPa. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 8-143723 (Claims, etc.) [Patent Document 2] JP 9-157456 (Claims, etc.) [Patent Document 3] Patent No. 4185375 (Claims, etc.) Summary of the Invention [Problem to be solved by the invention]

[0007] Meanwhile, in recent years, there has been a demand for environmentally friendly products, and products that reduce the environmental impact are desired. However, the waterproof sheets and the like in Patent Documents 1 to 3 are each composed only of petroleum-derived olefin resin, and therefore cannot satisfy the environmental characteristic of reducing CO2 emissions. In addition, depending on the amount of petroleum-derived olefin resin used, there is concern that excessive use of such resin may lead to problems such as accelerated depletion of resources. In order to solve this problem, the packaging industry and the like are considering using plant-derived olefins as olefin resins. However, when plant-derived olefins are used as materials for waterproof sheets, there are concerns that their mechanical properties will be inferior to those of conventional products using petroleum-derived olefins, and that they will not meet the durability required for waterproof sheets.

[0008] Therefore, the inventors conducted extensive research and discovered that by forming a waterproof sheet derived from an olefin resin composition that contains, either alone or in combination, polyolefin resins having plant-derived ethylene units and has a specified biomass content (sometimes referred to as plant content), and by specifying the tensile elongation (followability), bending resistance, etc., it is possible to achieve a satisfactory balance between environmental properties (reduced CO2 emissions) and mechanical properties, and thus completed the present invention. In other words, the present invention aims to provide a waterproof sheet that contains at least a first polyolefin resin derived from petroleum and a second polyolefin resin derived from plants, or that is substantially free of the first polyolefin resin derived from petroleum and is derived solely from the second polyolefin resin derived from plants, and that has excellent environmental properties and mechanical properties such as tensile elongation, as well as an efficient method for producing such a waterproof sheet. [Means for solving the problem]

[0009] According to the present invention, the waterproof sheet is either one of a waterproof sheet (hereinafter sometimes referred to as the first sheet) derived from an olefin resin composition containing, as component (A), a first polyolefin resin containing petroleum-derived ethylene units, and as component (B), a second polyolefin resin containing plant-derived ethylene units, or a waterproof sheet (hereinafter sometimes referred to as the second sheet) derived from component (B) alone, without containing component (A). Furthermore, there is provided a waterproof sheet characterized in that the first sheet and the second sheet have a biomass degree of the olefin resin composition conforming to ASTM D6866, which is within the range of more than 40% and 100%, and the average tensile elongation in the longitudinal direction and width direction (hereinafter sometimes simply referred to as tensile elongation) conforming to JIS K6251:2017, which is within the range of 650 to 1200%, thereby solving the above-mentioned problems. That is, it is possible to provide waterproof sheets (first sheet and second sheet) that are excellent in environmental characteristics and mechanical characteristics such as tensile elongation, as well as in water impermeability and ease of handling.

[0010] Furthermore, when constructing a waterproof sheet, it is preferable to include a reinforcing material as component (C) and set the blending amount of the reinforcing material within the range of 0.1 to 30 weight % when the total amount of the olefin resin composition is 100 weight %. By configuring it in this manner, the weather resistance and durability of the waterproof sheet can be significantly improved, and it becomes easier to adjust it to a predetermined range over a long period of time.

[0011] In forming the waterproof sheet, the component (A) is preferably a copolymer of petroleum-derived ethylene and an α-olefin having 3 to 12 carbon atoms. By configuring it in this manner, it is possible to improve the compatibility of component (A) with component (B), and it is also easy to precisely adjust the heat resistance and mechanical properties of the resulting waterproof sheet to within the specified range.

[0012] In forming the waterproof sheet, the component (B) is preferably a copolymer of plant-derived ethylene and an α-olefin having 3 to 12 carbon atoms. By configuring it in this manner, the compatibility of component (B) with component (A) can be improved, and further, it becomes easier to precisely adjust the heat resistance and mechanical properties, etc., of the resulting waterproof sheet to within the specified range.

[0013] In addition, when forming the waterproof sheet, it is preferable that the bending resistance in accordance with JIS L1096:2010 is set to a value within the range of 205 to 500 mN. By specifying the bending resistance, which indicates the rigidity of the film, in this manner, it becomes easy to precisely adjust the handleability of the resulting waterproof sheet, as well as the mechanical properties, within a predetermined range.

[0014] In forming the waterproof sheet, it is preferable that the thickness is within the range of 0.5 to 30 mm. Such a configuration not only makes it easier to use and manufacture the waterproof sheet, but also makes it easier to adjust the heat resistance, mechanical properties, etc., within predetermined ranges.

[0015] Another aspect of the present invention is a method for producing a waterproof sheet, comprising the following steps (1) and (2): Step (1): A step of mixing an olefin resin composition (sometimes referred to as a first resin composition) containing, as component (A), a first polyolefin resin containing petroleum-derived ethylene units and, as component (B), a second polyolefin resin containing plant-derived ethylene units, or preparing an olefin resin composition (sometimes referred to as a second resin composition) not containing component (A) and containing, as component (B), only a polyolefin resin containing plant-derived ethylene units, and adjusting the biomass degree in accordance with ASTM D6866 to a value within a range of more than 40% to 100%. Step (2): A step of forming a waterproof sheet derived from an olefin resin composition (a first resin composition and a second resin composition) and adjusting the average tensile elongation of the waterproof sheet in the longitudinal direction and the width direction to a value of 650 to 1200% or more in accordance with JIS K6251:2017. In other words, by using a specified manufacturing method that uses a specified olefin resin composition (first resin composition and second resin composition) as a raw material, it is possible to efficiently provide waterproof sheets (first sheet and second sheet) that have excellent environmental properties (reduced CO2 emissions) as well as excellent mechanical properties such as tensile elongation.

[0016] Furthermore, when carrying out the method for producing a waterproof sheet of the present invention, when the total amount of the olefin resin composition in step (1) is taken as 100% by weight, it is preferable that a reinforcing material is contained as component (C) and that the blending amount of the reinforcing material is within the range of 0.1 to 30% by weight. By implementing this method, the weather resistance and durability of the waterproof sheet can be significantly improved, and it becomes easier to adjust them to within a specified range over a long period of time. [Brief description of the drawings]

[0017] [Figure 1] Figure 1(a) is a diagram provided to explain how the waterproof sheet is used at a waste disposal site, Figure 1(b) is a side view provided to explain the bonding state of the waterproof sheet, and Figure 1(c) is a top view provided to explain the bonding state of the waterproof sheet. [Diagram 2] 2(a) to (d) are diagrams provided for explaining the configuration of the waterproof sheet (single layer structure, homogeneous and heterogeneous multi-layer structure, etc.). [Diagram 3] FIG. 3 is a diagram provided for explaining the relationship between the biomass ratio (%) of a waterproof sheet and the evaluation (relative value) of environmental characteristics. [Figure 4] FIG. 4 is a diagram provided for explaining the relationship between the biomass ratio (%) of a waterproof sheet and the tensile elongation percentage. [Diagram 5] FIG. 5 is a diagram provided for explaining the relationship between the biomass ratio (%) of a waterproof sheet and its bending resistance. [Figure 6] FIG. 6 is a diagram provided for explaining the relationship between the blending amount of component (B) in the olefin resin composition and the biomass degree of the water shielding sheet. [Figure 7] FIG. 7 is a diagram provided for explaining the relationship between the biomass ratio (%) of a waterproof sheet and the waterproofing evaluation (relative value). [Figure 8] FIG. 8 is a diagram provided for explaining the relationship between the biomass ratio (%) of a waterproof sheet and the evaluation (relative value) of the elastic modulus of the waterproof sheet. [Figure 9]FIG. 9 is a diagram provided for explaining the relationship between the biomass ratio (%) of a waterproof sheet and the tear strength of the waterproof sheet. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] [First embodiment] The first embodiment is either a waterproof sheet (first sheet) derived from an olefin resin composition (first resin composition) containing, as component (A), a first polyolefin resin containing petroleum-derived ethylene units and, as component (B), a second polyolefin resin containing plant-derived ethylene units, or a waterproof sheet (second sheet) derived from an olefin resin composition (second resin composition) that is substantially free of component (A) and contains only component (B). The waterproof sheet (first sheet and second sheet) is characterized in that the biomass degree of the olefin resin composition conforming to ASTM D6866 is within the range of more than 40% to 100%, and the average tensile elongation in the longitudinal direction and width direction is within the range of 650 to 1200% conforming to JIS K6251:2017. The waterproof sheet of the first embodiment will be specifically described below with reference to the drawings as appropriate.

[0019] 1. Basic structure of waterproof sheet The basic structure of a waterproof sheet is a waterproof sheet 10 (which also includes a resin sheet made by rolling up a long waterproof sheet into a roll) that is laid on the surface of a slope such as a developed area 14 of a waste disposal site, as shown in Figure 1(a). Such waterproof sheets adopt the configurations shown in Figs. 2(a) to (d) according to the application. Normally, water that accumulates in the developed land 14 of a waste disposal site where such waterproof sheets are laid is drained outside the site through drainage pipes.

[0020] On the other hand, the waterproof sheet 10 is a resin sheet derived from a specified olefin resin composition that is laid directly or indirectly on the developed land 14 of a waste disposal site to prevent water (contaminated water) flowing out from the waste 12 from seeping into the soil and to exert a waterproofing effect on the surface on which it is laid for a long period of time. Such waterproof sheets are basically composed of an olefin resin composition (first resin composition) containing, as component (A), a first polyolefin resin containing petroleum-derived ethylene units, and, as component (B), a second polyolefin resin containing plant-derived ethylene units, or an olefin resin composition (second resin composition) that is substantially free of component (A) and contains only component (B), and have excellent water-proofing and environmental properties as well as predetermined mechanical properties such as tensile elongation and bending resistance.

[0021] 2. Olefin resin composition The olefin resin composition constituting the waterproof sheet is a resin composition (first resin composition) comprising, as component (A), a first polyolefin resin containing petroleum-derived ethylene units, and as component (B), a second polyolefin resin containing plant-derived ethylene units, or a resin composition (second resin composition) which is substantially free of component (A) and comprises only component (B). In other words, such a waterproof sheet (first sheet) is characterized in that it is derived from an olefin resin composition (first resin composition) containing, as component (A), a first polyolefin resin containing petroleum-derived ethylene units, and, as component (B), a second polyolefin resin containing plant-derived ethylene units. Alternatively, such a waterproof sheet (second sheet) is characterized in that it is derived from an olefin resin composition (second resin composition) that contains, as component (A), substantially no first polyolefin resin containing petroleum-derived ethylene units, and, as component (B), a second polyolefin resin containing plant-derived ethylene units. The reason for using the specified olefin resin composition is that it has environmental characteristics that reduce the environmental load, and can exhibit specified mechanical characteristics such as high tensile elongation and bending resilience.

[0022] (1)(A) Component 1) Type The type of monomer constituting the petroleum-derived ethylene unit constituting component (A) is not particularly limited, so long as it is an ethylene monomer obtained by polymerizing a first polyolefin resin containing at least an ethylene unit using a specified catalyst (such as a Ziegler-Natta catalyst or a metallocene catalyst). Moreover, component (A) differs from component (B) described below, in that it is a petroleum-derived resin that is derived from plants and does not substantially contain ethylene units. As the type of monomer that constitutes the petroleum-derived ethylene unit that constitutes the component (A), it is preferable to blend an α-olefin having 3 to 12 carbon atoms that copolymerizes with the ethylene monomer as a copolymerization monomer. The reason for this is that by using component (A) as an ethylene-based copolymer, the compatibility between component (A) and component (B) can be improved, and various mechanical properties, thermal properties, polymerizability, and the like of component (A) can also be improved. Therefore, it is preferable to use, as the α-olefin having 3 to 12 carbon atoms, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, etc., either alone or in combination of two or more thereof.

[0023] 2) Biomass content The biomass content of the first polyolefin resin constituting the component (A) is essentially 0% since it does not contain C14, which is an isotope of C12. However, in order to improve the compatibility with the component (B), the biomass degree of the first polyolefin resin as the component (A) is more preferably 1% or less, and even more preferably 0.1% or less. The biomass degree of the first polyolefin resin can be measured in accordance with ASTM D6866, similarly to the biomass degree of the second polyolefin resin etc. described below.

[0024] 3) Blend amount It is preferable to determine the amount of the first polyolefin resin that constitutes the (A) component, taking into consideration the amount of the (B) component used in combination, so that the biomass degree of the olefin resin composition that constitutes the waterproof sheet is within the range of more than 40% to 100%. The reason for this is that if the biomass ratio is 40% or less, it may become difficult to achieve both mechanical properties such as tensile elongation and environmental properties. Therefore, it is more preferable to set the biomass degree to a value within the range of 45% to 95%, and even more preferable to set the biomass degree to a value within the range of 50% to 90%. More specifically, in order to adjust the biomass degree, the ratio of the blending amount of the first polyolefin resin to the blending amount of the second polyolefin resin is preferably set to a value within the range of 0 / 100 to 50 / 50 in weight conversion. The reason for this is that if the ratio of the amount of the first polyolefin resin to the amount of the second polyolefin resin is outside of this range, it may become difficult to adjust the biomass content of the olefin resin composition or to adjust the tensile elongation or bending resistance. Therefore, when the total amount of the olefin resin composition is taken as 100% by weight, the amount of the first polyolefin resin is preferably 0 to 50% by weight, more preferably 0 to 30% by weight, and even more preferably 0 to 20% by weight. Furthermore, when the blending amount of the first polyolefin resin is 0% by weight, the waterproof sheet corresponds to the above-mentioned second sheet, and in other cases, it corresponds to the first sheet. Furthermore, the biomass content of the second polyolefin may vary somewhat depending on the purity of the biomass-derived pellets used. Therefore, it is preferable to set the amount of the first polyolefin resin and the amount of the second polyolefin resin in accordance with the purity of the biomass-derived pellets used so that the olefin resin composition constituting the waterproof sheet has the desired biomass content.

[0025] 4) Weight average molecular weight / melt flow rate In the first polyolefin resin constituting the component (A), there are no particular limitations on its weight average molecular weight, and it can be changed appropriately according to the desired physical properties. In addition, in view of the mechanical properties of the waterproof sheet, it is preferable that the weight average molecular weight is set to a value within the range of 120,000 to 200,000. The reason for this is that if the weight average molecular weight of the first polyolefin resin is less than 120,000 or, conversely, exceeds 200,000, its compatibility with the second polyolefin resin decreases, and the water impermeability, mechanical properties such as tensile elongation, and durability of the water-proof sheet of the first embodiment may be significantly reduced. Therefore, in the blending amount of the first polyolefin resin, the weight average molecular weight is more preferably set to a value within the range of 150,000 to 190,000, and further preferably to a value within the range of 160,000 to 185,000. For the sake of clarity, it is preferable that the weight average molecular weight of the first polyolefin resin is smaller than that of the second polyolefin resin.

[0026] The first polyolefin resin constituting component (A) preferably has a melt flow rate (MFR) in accordance with JIS K7210:1999 within the range of 1 to 3 g / 10 min under conditions of 190° C. and a load of 2.16 kg. The reason for this is that if the melt flow rate of the first polyolefin resin is less than 1 g / 10 min, the fluidity is poor, and the compatibility with the second polyolefin resin may decrease. Moreover, if the melt flow rate of the first polyolefin resin exceeds 3 g / 10 min, the viscosity may be too low, making molding difficult. Therefore, the melt flow rate of the first polyolefin resin is more preferably set to a value within the range of 1.3 to 2.8 g / 10 minutes, and further preferably set to a value within the range of 1.5 to 2.5 g / 10 minutes.

[0027] 5) Density The density of the first polyolefin resin constituting the component (A) is not particularly limited and can be appropriately changed according to the desired physical properties. From the viewpoint of the strength of the waterproof sheet, however, it is usually 0.88 to 0.94 g / cm. 3 It is preferable to set the value within the range. The reason for this is that the density of the first polyolefin resin is 0.88 g / cm 3 The value may be less than 0.94g / cm 3 If the value exceeds this value, the compatibility with the second polyolefin resin will decrease, and the water impermeability, mechanical properties such as tensile elongation, and durability of the water-resistant sheet of the first embodiment may be significantly reduced. Therefore, in the first polyolefin resin, the density is set to 0.90 to 0.915 g / cm 3 More preferably, the value is within the range of 0.905 to 0.912 g / cm 3 It is more preferable that the value is within the range of . For the sake of clarity, it is preferable that the density of the first polyolefin resin is greater than the density of the second polyolefin resin.

[0028] 6) Melting point When the first polyolefin resin constituting the component (A) shows a crystalline melting peak as measured by DSC (differential scanning calorimeter) or the like, it is determined that the resin has a melting point corresponding to the temperature of the peak value. The melting point is not particularly limited and can be changed appropriately according to the desired physical properties, but it is usually preferable to set it to a value within the range of 85 to 125°C. The reason for this is that if the melting point of the first polyolefin resin is less than 85°C or more than 125°C, the mechanical properties of the olefin resin composition may be significantly reduced, or the compatibility with the second polyolefin resin may be reduced. Therefore, the melting point of the first polyolefin resin is more preferably set to a value within the range of 87 to 120°C, and even more preferably to a value within the range of 90 to 115°C. For the sake of clarity, it is preferable that the melting point of the first polyolefin resin is lower than the melting point of the second polyolefin resin.

[0029] It is also preferable that the first polyolefin resin constituting the component (A) has a melting enthalpy (ΔH) measured by DSC or the like within a range of 90 to 130 mJ / mg. More specifically, it is preferable that the crystallinity value of the first polyolefin resin constituting the component (A) is limited to a value within the range of 30 to 50%. It is preferable that the melting enthalpy (ΔH) and the crystallinity of the first polyolefin resin are smaller than those of the second polyolefin resin.

[0030] 7) Elastic modulus (1% secant elastic modulus) The 1% secant elastic modulus (hereinafter, simply referred to as elastic modulus) of the first polyolefin resin constituting the component (A) is not particularly limited and can be appropriately changed according to the desired physical properties. However, it is usually 80 to 180 N / mm 2 It is preferable to set the value within the range. The reason for this is that the elastic modulus of the first polyolefin resin is 80 N / mm 2 The value may be less than 180N / mm 2 If the value exceeds this range, the mechanical properties and handleability of the olefin resin composition may be significantly reduced, and the compatibility with the second polyolefin resin may be reduced. Therefore, the elastic modulus of the first polyolefin resin is set to 90 to 170 N / mm 2 It is more preferable to set the value within the range of 100 to 120 N / mm 2 It is more preferable that the value is within the range of . In addition, as shown in Example 1, the first polyolefin resin was formed into a film by a predetermined method, and the 1% secant elastic modulus was calculated as the stress value at a strain of 1% in the stress-strain curve measured in accordance with JIS K7127:1999 divided by the cross-sectional area and strain. A more specific calculation method will be described in Example 1.

[0031] 8) Hayes Furthermore, the haze value, which is an index showing the transparency of the first polyolefin resin constituting the component (A) and is determined in accordance with JIS K7136:2000, is preferably set to a value within the range of 0.5 to 15%. The reason for this is that if the haze of the first polyolefin resin is less than 0.5% or, conversely, exceeds 15%, the yield during production of the olefin resin composition, mechanical properties, and even handleability may be significantly reduced, and the compatibility with the second polyolefin resin used in combination may be reduced. Therefore, in the first polyolefin resin, the haze is more preferably set to a value within the range of 1 to 12%, and further preferably to a value within the range of 3 to 10%. For clarity, it is preferable that the haze of the first polyolefin resin is greater than the haze of the second polyolefin resin.

[0032] (2)(B) Component 1) Type Component (B) is an olefin polymer derived from ethylene monomers (which may contain oligomers in some cases; the same applies below) produced from alcohol obtained using plants as raw materials, and means that it contains ethylene units derived from plant raw materials. That is, component (B) is a polymer obtained by subjecting ethylene monomer, which is derived from a plant as a raw material, to coordination-insertion polymerization or the like to form a second polyolefin resin having predetermined properties. Therefore, as the second polyolefin resin, which is component (B), a commercially available product can be used, and examples of the commercially available product include at least one of SLL118, SLL118 / 21, SLL218, SLL318, SLH118, SLH218, SLH318, SLH082 / 30AF, SBC818, SBP208, SPB681, SGF4960, STN7006, etc., manufactured by Braskems.

[0033] The second polyolefin resin constituting the component (B) may be a polyolefin resin produced by employing a mass balance method certified by, for example, ISCC PLUS certification. Polyolefin resins classified as biomass products using the mass balance method contribute to reducing the environmental impact when considering the overall production, use, and disposal of various products in the petrochemical industry, and can be used in the same manner as the second polyolefin resin constituting component (B).

[0034] In addition, in the second polyolefin resin constituting the component (B), it is preferable to blend an α-olefin having 3 to 12 carbon atoms, which is copolymerizable with the plant-derived ethylene monomer component, as a copolymerization component. The reason for this is that by blending such a copolymerization component, the compatibility between the second polyolefin resin constituting the component (B) and the component (A) can be improved, and various mechanical properties, thermal properties, etc. of the component (B) can also be improved. Therefore, it is possible to use monomers similar to the α-olefins having 3 to 12 carbon atoms that are blended into component (A). However, it is particularly preferable to use 1-butene, 1-pentene, 1-hexene, 1-octene, etc., either alone or in combination of two or more thereof, in component (B).

[0035] 2) Biomass ratio Basically, from the viewpoint of environmental consideration, the biomass degree of the second polyolefin resin constituting the component (B) is preferably within a range of 80 to 100%. However, in order to improve compatibility with the (A) component, it is more preferable to set the biomass degree of the second polyolefin resin constituting the (B) component to a value within the range of 85 to 98%, and even more preferable to set it to a value within the range of 90 to 97%.

[0036] 3) Blend amount The amount of the second polyolefin resin contained in the component (B) is preferably determined so that the biomass degree of the olefin resin composition falls within a range of from more than 40% to 100%. The reason for this is that if the biomass ratio is 40% or less, it may become difficult to achieve both mechanical properties such as tensile elongation and environmental properties. Therefore, it is more preferable to set the biomass degree to a value within the range of 45% to 95%, and even more preferable to set the biomass degree to a value within the range of 50% to 90%. More specifically, in order to adjust the biomass degree, the ratio of the blending amount of the second polyolefin resin to the blending amount of the first polyolefin resin is preferably set to a value within the range of 100 / 0 to 50 / 50 in weight conversion. The reason for this is that if the ratio of the blending amount of the second polyolefin resin to the blending amount of the first polyolefin resin is outside this range, it may become difficult to adjust the biomass content of the olefin resin composition or to adjust the tensile elongation and bending resistance. Therefore, when the total amount of the olefin resin composition is 100% by weight, the amount of the second polyolefin resin is preferably 50 to 100% by weight, more preferably 70 to 100% by weight, and even more preferably 80 to 100% by weight. Furthermore, when the blending amount of the second polyolefin resin is 100% by weight, the waterproof sheet corresponds to the above-mentioned second sheet, and in other cases, it corresponds to the first sheet. Furthermore, the biomass content of the second polyolefin may vary somewhat depending on the purity of the biomass-derived pellets used. Therefore, it is preferable to set the amount of the second polyolefin resin and the amount of the first polyolefin resin in accordance with the purity of the biomass-derived pellets used so that the olefin resin composition constituting the waterproof sheet has the desired biomass content. Furthermore, if the biomass content of the olefin resin composition that constitutes the waterproof sheet is 10% or more, it can be given the biomass mark of the Organic Resources Association.

[0037] Here, referring to FIG. 3, the relationship between the biomass ratio (%) of a waterproof sheet containing component (B) and the like and the evaluation (relative value) of the environmental characteristics based on the amount of CO2 emissions will be described. That is, the horizontal axis of FIG. 3 shows the biomass ratio (%) of the waterproof sheet, and the vertical axis shows the evaluation value of the environmental characteristics based on the amount of CO2 emissions. The environmental characteristics based on the CO2 emissions were evaluated according to the criteria shown in Example 1, and the evaluation value (relative value) of the environmental characteristics was calculated using the following criteria: ◎ is 5 points, ○ is 3 points, △ is 1 point, and × is 0 point. Furthermore, as shown by the characteristic curve in Figure 3, in the range of 0 to 40% biomass ratio (%) of the waterproof sheet, there is a tendency for the evaluation value of the environmental characteristics of the waterproof sheet to increase as the biomass ratio (%) increases. It can also be seen that when the biomass ratio (%) of the waterproof sheet is in the range of values ​​greater than 40%, the sheet has high evaluation results for environmental characteristics. Therefore, by limiting the biomass ratio (%) of the waterproof sheet to a value within a predetermined range, it is possible to adjust the CO2 emission amount of the waterproof sheet to a value within the range. As will be described later, it has been found that the biomass degree of a waterproof sheet has a certain correlation with the average tensile elongation in the longitudinal and transverse directions of the waterproof sheet, as shown in Figure 4, the bending resistance of the waterproof sheet, as shown in Figure 5, the amount of component (B) in the olefin resin composition, as shown in Figure 6, and the tear strength of the waterproof sheet, as shown in Figure 9.

[0038] 4) Weight average molecular weight / melt flow rate The weight average molecular weight of the second polyolefin resin constituting the component (B) is not particularly limited and can be changed appropriately according to the desired physical properties, but it is usually preferable to set it to a value within the range of 170,000 to 250,000. The reason for this is that if the weight average molecular weight of the second polyolefin resin is less than 170,000 or exceeds 250,000, its compatibility with the first polyolefin resin decreases, and the water impermeability, mechanical properties such as tensile elongation, and durability of the resulting waterproof sheet may be significantly reduced. Therefore, in the blending amount of the second polyolefin resin, the weight average molecular weight is more preferably set to a value within the range of 180,000 to 240,000, and further preferably to a value within the range of 190,000 to 220,000. For the sake of clarity, it is preferable that the weight average molecular weight of the second polyolefin resin is greater than that of the first polyolefin resin.

[0039] On the other hand, the second polyolefin resin constituting the component (B) preferably has a melt flow rate (MFR) in accordance with JIS K7210:1999 within the range of 1.8 to 2.7 g / 10 min under conditions of 190° C. and a load of 2.16 kg. The reason for this is that if the melt flow rate of the second polyolefin resin is less than 1.8 g / 10 min, the fluidity is poor, and the compatibility with the first polyolefin resin may decrease. On the other hand, if the melt flow rate of the second polyolefin resin exceeds 2.7 g / 10 min, the viscosity may be too low, making molding difficult. Therefore, the melt flow rate of the second polyolefin resin is more preferably set to a value within the range of 2 to 2.6 g / 10 minutes, and even more preferably set to a value within the range of 2.1 to 2.5 g / 10 minutes.

[0040] 5) Density The density of the second polyolefin resin constituting the component (B) is not particularly limited and can be changed appropriately according to the desired physical properties. From the viewpoint of the strength of the waterproof sheet, however, it is usually 0.9 to 0.93 g / cm. 3 It is preferable to set the value within the range. The reason for this is that the density of the first polyolefin resin is 0.9 g / cm 3 or less than 0.93 g / cm 3 If the value exceeds this value, the compatibility with the first polyolefin resin decreases, and the water impermeability, mechanical properties such as tensile elongation, and durability of the resulting waterproof sheet may be significantly reduced. Therefore, in the second polyolefin resin, the density is set to 0.905 to 0.925 g / cm 3 More preferably, the value is within the range of 0.91 to 0.92 g / cm 3 It is more preferable that the value is within the range of . For the sake of clarity, it is preferable that the density of the second polyolefin resin is greater than the density of the first polyolefin resin.

[0041] 6) Melting point When the second polyolefin resin constituting the component (B) shows a crystalline melting peak as measured by DSC or the like, it is determined that the second polyolefin resin has a melting point corresponding to the temperature of the peak value. The melting point is not particularly limited and can be changed appropriately according to the desired physical properties, but it is usually preferable to set it to a value within the range of 95 to 135°C. The reason for this is that if the melting point of the second polyolefin resin is less than 95°C or more than 135°C, the mechanical properties of the waterproof sheet derived from the olefin resin composition may be significantly reduced, or its compatibility with the first polyolefin resin may be reduced. Therefore, the melting point of the second polyolefin resin is more preferably set to a value within the range of 105 to 132°C, and even more preferably to a value within the range of 120 to 130°C. For the sake of clarity, it is preferable that the melting point of the second polyolefin resin is greater than that of the first polyolefin resin.

[0042] It is also preferable that the second polyolefin resin constituting the component (B) has a melting enthalpy (ΔH) measured by DSC or the like within a range of 110 to 150 mJ / mg. More specifically, it is preferable that the second polyolefin resin constituting the component (B) has a crystallinity value limited to a value within the range of 35 to 50%. It is preferable that the melting enthalpy (ΔH) and the degree of crystallinity of the second polyolefin resin are greater than those of the first polyolefin resin.

[0043] 7) Elastic modulus (1% secant elastic modulus) The 1% secant elastic modulus of the second polyolefin resin constituting the component (B) is not particularly limited and can be appropriately changed according to the desired physical properties, but is usually 180 to 250 N / mm 2 It is preferable to set the value within the range. The reason for this is that the elastic modulus of the second polyolefin resin is 180 N / mm 2 The value may be less than 250N / mm 2 If the value exceeds this limit, the mechanical properties and handleability of the olefin resin composition may be significantly reduced, and the compatibility with the first polyolefin resin used in combination may be reduced. Therefore, the elastic modulus of the second polyolefin resin is set to 185 to 230 N / mm 2 It is more preferable to set the value within the range of 190 to 210 N / mm 2 It is more preferable that the value is within the range of . As described above, the 1% secant elastic modulus was calculated from a stress-strain curve obtained by forming the second polyolefin resin into a film by a predetermined method in accordance with JIS K7127:1999.

[0044] 8) Hayes Furthermore, the haze value, which is an index showing the transparency of the second polyolefin resin constituting the component (B) and is determined in accordance with JIS K7136:2000, is preferably set to a value within the range of 0.5 to 15%. The reason for this is that if the haze of the second polyolefin resin is less than 0.5% or, conversely, exceeds 15%, the transparency and mechanical properties of the olefin resin composition may be significantly reduced, and the compatibility with the first polyolefin resin used in combination may be reduced. Therefore, in the second polyolefin resin, the haze is more preferably set to a value within the range of 1 to 12%, and further preferably set to a value within the range of 2 to 10%. For clarity, it is preferable that the haze of the second polyolefin resin is smaller than the haze of the first polyolefin resin.

[0045] (3)(C) component 1) Type The (C) component is a reinforcing material (however, it may be referred to as a carbon compound such as typical examples being carbon black and carbon fiber), and it is preferable that the reinforcing material is blended with a polyolefin resin composition which is a mixture of a first polyolefin resin and a second polyolefin resin. Therefore, the representative type of component (C) is a fiber of a carbon compound consisting of at least one of polyvinyl alcohol-based synthetic fiber, polypropylene fiber, nylon fiber, polyester fiber, rayon fiber, acrylic fiber, carbon fiber, etc., because it is likely to exhibit excellent light weight, economy, ease of handling, mechanical strength, weather resistance, etc. Also, inorganic fibers such as glass fiber can be used. In addition, particles or powder of a carbon compound consisting of at least one of carbon nanotubes, graphene, graphite, carbon black (furnace carbon black, acetylene carbon black), etc. are also preferred, since they are easy to exhibit excellent light weight, economy, mixing and dispersibility, mechanical strength, weather resistance, etc., and are also easy to form into a multilayer structure, and carbon black is particularly preferred.

[0046] 2)Containing amount When the total amount of the olefin resin composition is taken as 100% by weight, it is preferable to blend a reinforcing material as component (C) and set the blending amount of the reinforcing material to a value within the range of 0.1 to 30% by weight. The reason for this is that if the amount of the reinforcing material is less than 0.1% by weight, the effect of improving the weather resistance, mechanical properties such as strength, and the like of the waterproof sheet may not be obtained. On the other hand, if the amount of the reinforcing material exceeds 30% by weight, the tensile elongation of the resulting waterproof sheet will decrease significantly, and the durability against tensile stress may decrease. Therefore, the amount of the reinforcing material to be mixed is more preferably within a range of 0.5 to 15% by weight, and even more preferably within a range of 1 to 10% by weight.

[0047] 3) Average particle size / average fiber length, etc. Furthermore, when the reinforcing material is a fiber such as carbon fiber, it is preferable that the average fiber diameter is within a range of 3 to 500 nm and the average fiber length is within a range of 1 to 1000 μm. On the other hand, when the reinforcing material is in the form of particles or granules such as carbon particles, the average particle size is preferably within the range of 3 to 500 nm, more preferably within the range of 10 to 300 nm, and even more preferably within the range of 20 to 150 nm. The average fiber diameter or length of fibers, or the average particle size of particles, etc., can be measured from electron microscope photographs in accordance with JIS Z8901:2006, and calculated by image analysis of the measurements.

[0048] (4) Additives Furthermore, additives that may be blended as necessary include various polyolefin resins such as high density polyethylene, linear low density polyethylene, high pressure polyethylene, and polypropylene other than component (A) and component (B); resin components such as natural rubber, synthetic rubber, and thermoplastic elastomer; as well as tackifiers, crosslinking agents, various fillers such as calcium carbonate, talc, silica, and metal fibers; antioxidants, ultraviolet absorbers, light stabilizers, flame retardants, colorants, and the like.

[0049] When these additives are added, the amount of the additives to be added will vary depending on the type of additive, but is usually preferably within the range of 0.1 to 20% by weight, more preferably within the range of 0.5 to 10% by weight, and even more preferably within the range of 1 to 5% by weight, when the olefin resin composition is 100% by weight.

[0050] (5) Biomass content of olefin resin composition When the olefin resin composition obtained by mixing the components (A) and (B) is used as is as a waterproof sheet, the biomass degree of the waterproof sheet is the same as the biomass degree of the waterproof sheet. That is, it can be measured using a C14 accelerator mass spectrometer (AMS) in accordance with ASTM D6866. The olefin resin composition is characterized in that the biomass ratio is set to a value within the range of more than 40% to 100%. The reason for this is that when the biomass ratio of such an olefin resin composition is a value of 40% or less, consideration of environmental characteristics becomes less and may become insufficient. On the other hand, if only high purity biomass is selected for production so that the biomass content of such an olefin resin composition becomes 100%, production efficiency will be poor. Therefore, the biomass degree of such an olefin resin composition is more preferably set to a value within the range of 45 to 95%, and further preferably to a value within the range of 50 to 90%.

[0051] (6) Thermal properties of olefin resin compositions The thermal properties of the olefin resin composition obtained by mixing components (A) and (B), such as the melting point and crystallization enthalpy values ​​showing the crystalline peak, can basically be regarded as the same as the thermal properties of the waterproof sheet when the olefin resin composition is used as it is as a waterproof sheet. Therefore, the thermal properties of such an olefin resin composition will be described later as a waterproof sheet.

[0052] (7) Mechanical properties of olefin resin composition The mechanical properties of the olefin resin composition obtained by mixing components (A) and (B), such as tensile elongation and bending resistance, can basically be considered to be the same as the mechanical properties of the waterproof sheet when the olefin resin composition is used as is as a waterproof sheet. Therefore, the mechanical properties of such an olefin resin composition will be described later as a waterproof sheet.

[0053] (8) Flow properties of olefin resin compositions The flow characteristics, such as the melt flow rate, of the olefin resin composition obtained by mixing the (A) component and the (B) component can basically be regarded as being the same as the melt flow rate of the waterproof sheet when the olefin resin composition is used as it is. Therefore, the flow characteristics of such an olefin resin composition will be described later in relation to a waterproof sheet.

[0054] 5. Characteristics of waterproof sheets (1) Basic configuration 1) Single layer As shown in Figure 2(a), the waterproof sheet 10 is a resin sheet derived from a specified olefin resin composition containing a specified first olefin resin and a second olefin resin having a specified biomass degree, and may basically be a single layer so long as it has specified mechanical properties (tensile elongation, bending resistance, etc.). Such a single-layer waterproof sheet is not only relatively easy and stable to install at waste disposal sites and to manufacture, but also makes it easy to adjust the desired waterproofing properties and mechanical properties (such as tensile elongation and bending resistance). FIG. 2(a) shows an embodiment of a waterproof sheet 10 containing a reinforcing material (carbon black, carbon fiber, or the like) 10a in a predetermined first olefin resin 10b.

[0055] 2) Multilayer structure Furthermore, the waterproof sheet may be a homogeneous multilayer structure 30 comprising multiple resin sheets (10, 10') made from a specified olefin resin composition, stacked together, as shown in FIG. 2(b). Waterproof sheets are prepared by co-extrusion molding or heat lamination, or by preparing multiple resin layers as the basic components of such waterproof sheets, usually in the range of 2 to 50 layers, and directly heat pressing them to form a multilayer structure, or it is also preferable to indirectly laminate them via an adhesive or the like to form a homogeneous multilayer structure. A waterproof sheet having such a multi-layer structure can be used for a wider range of applications and can more easily satisfy various required characteristics. Therefore, when multiple waterproof sheets are stacked to form a multi-layer waterproof sheet, it is preferable for the number of layers to be a value within the range of 2 to 50 sheets, more preferably a value within the range of 3 to 20 sheets, and even more preferably a value within the range of 4 to 10 sheets. FIG. 2(b) shows an embodiment of a homogeneous multilayer structure 30 formed by stacking multiple single-layer waterproof sheets 10, 10' each containing a reinforcing material (such as carbon black) in a specified first olefin resin 10b.

[0056] Also preferred is a heterogeneous multilayer structure 32, which is formed by laminating, on one side of the reinforcing material-containing waterproof sheet 10 of the present invention, a non-reinforcing material-containing resin sheet or a heterogeneous waterproof sheet 24 containing a colorant (titanium oxide, zinc oxide, or other coloring pigment), as shown in Figure 2(c). For example, there are waterproof sheets with a white upper layer and a black lower layer, and waterproof sheets with a heterogeneous multi-layer structure in which the upper layer is non-conductive and the lower layer is conductive. The reason for this is that it makes it easier to distinguish between the front and back sides of the waterproof sheet as a whole, and if the waterproof sheet is damaged after installation, the white layer on the front side will be scraped off and the black color on the back side will be exposed, making it possible to immediately detect the damage to the waterproof sheet. A waterproof sheet with a multi-layer structure including resin layers made of different materials like this has even greater versatility, can be used in a wider range of applications, and is more likely to satisfy the various required characteristics. FIG. 2(c) shows an embodiment of a heterogeneous multilayer structure 32 formed by stacking a single-layer waterproof sheet 10 containing a reinforcing material (such as carbon black) 10a in a specified first olefin resin 10b, and a waterproof sheet 24 containing a specified first olefin resin 24b and a white pigment 24a such as titanium oxide or zinc oxide. Needless to say, it is also preferable to use a multi-layer structure consisting of a laminate of other resin layers, woven fabric layers, nonwoven fabric layers, metal layers, ceramic layers, and wood instead of the dissimilar waterproof sheet 24.

[0057] Furthermore, as shown in Figure 2(d), a sandwich-structured multilayer structure 34 is shown in which a single-layer waterproof sheet 10 containing a reinforcing material (such as carbon black) as an intermediate layer is prepared, and waterproof sheets 24, 24' containing a predetermined first olefin resin and a pigment such as titanium oxide are prepared on both sides of the intermediate layer, and then these are laminated together. In addition, it is also preferable to use a waterproof sheet with a three-layer structure, in which the resin sheet of the first embodiment is used as the middle layer, and resin sheets of different materials are used on the front and back sides, respectively, to form a waterproof sheet with a sandwich structure. Needless to say, it is also preferable to use a multi-layer structure consisting of a laminate of other resin layers, woven fabric layers, non-woven fabric layers, metal layers, ceramic layers, or wood instead of one or both of the waterproof sheets 24, 24'.

[0058] Furthermore, since the developed land for a waste disposal site usually has a vast area, it is preferable to prepare a large number of waterproof sheets having a specified unit area to correspond to that vast area. As shown in Figures 1(b) to (c), it is also preferable to use a self-propelled fusion machine or a manual fusion machine or an extrusion welding machine (not shown) to partially overlap the ends of waterproof sheets 10 and 10' having a specified unit area, and then heat-weld them at multiple locations, such as joints 22 and 22', or to overlap them by other methods to produce a large-area waterproof sheet that exhibits a specified waterproofing property.

[0059] (2) Tensile elongation The waterproof sheet is characterized by having a tensile elongation in the range of 650 to 1200%, which complies with JIS K6251:2017, based on the Planning, Design and Management Guidelines for the Development of Final Waste Disposal Sites (2010 revised edition, National Urban Cleaning Conference, hereinafter sometimes referred to as the Management Guidelines). The reason for this is that if the tensile elongation is less than 650%, the material will be easily damaged when it conforms to uneven surfaces or in the unlikely event of ground subsidence. However, if the tensile elongation value of the waterproof sheet exceeds 1200%, the range of selection of the types of usable olefin resin compositions may become excessively narrow. Therefore, it is more preferable that the tensile elongation of such a waterproof sheet is set to a value within the range of 680 to 1100%, and even more preferable that it is set to a value within the range of 700 to 1000%. Furthermore, if the tensile elongation of such waterproof sheet is 650% or more, it has the advantage of satisfying the synthetic resin-based, medium elasticity type of the above-mentioned management guidelines.

[0060] Here, referring to FIG. 4, the relationship between the biomass ratio (%) of a waterproof sheet and the tensile elongation will be explained. That is, the horizontal axis of FIG. 4 indicates the biomass ratio (%) of the waterproof sheet, and the vertical axis indicates the tensile elongation value of the waterproof sheet. As the characteristic curve in FIG. 4 shows, up to a biomass content (%) of about 5 to 10% in the waterproof sheet, the tensile elongation value of the waterproof sheet remains almost unchanged as the blend ratio increases. Next, when the biomass content (%) exceeds 10% and reaches approximately 40%, there is a tendency for the tensile elongation of the waterproof sheet to increase as the biomass content increases. Furthermore, when the biomass ratio (%) of the waterproof sheet exceeds 40%, there is a clear tendency for the tensile elongation value of the waterproof sheet to increase as the biomass ratio increases. Therefore, by limiting the biomass ratio (%) of the waterproof sheet to a value within a predetermined range, the tensile elongation of the waterproof sheet can be set to a value within a predetermined range (650 to 1200%). The tensile elongation of the waterproof sheet can be adjusted to a value within a desired range by adjusting the biomass ratio of the waterproof sheet, for example, as judged from the characteristic curve in FIG.

[0061] (3) Bending resistance Moreover, it is preferable that the water shielding sheet has a bending resistance (sometimes called Gurley bending resistance) in accordance with JIS L1096:2010 within a range of 205 to 500 mN. The reason for this is that if the bending resistance is less than 205 N / cm, the bending resilience is small and the film may become vulnerable to impact. On the other hand, if the bending resistance exceeds 500 mN, the composition may become too rigid, resulting in poor handleability, or the range of options for the types of olefin resin compositions that can be used may become excessively narrow. Therefore, it is more preferable that the bending resistance of such a waterproof sheet is set to a value within the range of 230 to 400 mN, and even more preferable that it is set to a value within the range of 250 to 350 mN.

[0062] Here, referring to FIG. 5, the relationship between the biomass ratio (%) of a waterproof sheet and the bending resistance of the waterproof sheet will be described. That is, the horizontal axis of FIG. 5 indicates the biomass ratio (%) of the waterproof sheet, and the vertical axis indicates the bending resistance value of the waterproof sheet. As the characteristic curve in FIG. 5 shows, there is a tendency for the bending resistance of the waterproof sheet to increase as the biomass ratio (%) of the waterproof sheet increases, up to about 5-60%. Next, when the biomass ratio (%) exceeds about 70%, the bending resistance of the waterproof sheet tends to decrease as the ratio increases. In any case, by restricting the biomass degree (%) of the waterproof sheet to a value within a predetermined range, it is possible to obtain a waterproof sheet having a predetermined bending resistance (205 to 500 mN). The bending resistance of the waterproof sheet can be adjusted to a value within a desired range by adjusting the biomass ratio of the waterproof sheet, for example, based on the characteristic curve in FIG.

[0063] Furthermore, referring to FIG. 6, the relationship between the blending amount of component (B) in the olefin resin composition and the biomass degree of the water shielding sheet will be explained. That is, the blending amount of component (B) in the olefin resin composition has a strong correlation with the biomass degree of the waterproof sheet. Therefore, if the blending amount of component (B) is, for example, 50% by weight or more, the biomass degree of the waterproof sheet can be set to a predetermined value of 42% or more. Therefore, judging from the characteristic curve in Figure 6, it can be said that by adjusting the amount of component (B), the biomass degree of the waterproof sheet can be adjusted to the desired range, and therefore the tensile elongation of the waterproof sheet as shown in Figure 4, the bending resistance of the waterproof sheet as shown in Figure 5, and the tear strength of the waterproof sheet as shown in Figure 9 can each be adjusted to values ​​within the specified ranges.

[0064] (4) Thickness It is preferable that the thickness of the waterproof sheet, measured in accordance with JIS K6250:2019, is within the range of 0.5 to 30 mm. The reason for this is that if the thickness is less than 0.5 mm, the mechanical properties such as bending resistance and handleability may be significantly reduced, or the manufacturing costs may increase due to yield factors. On the other hand, if the thickness exceeds 30 mm, the conformability to the surface and handling properties will decrease, and furthermore, in relation to the amount of raw materials used, the manufacturing costs will increase excessively, which may be economically disadvantageous. Also, as the thickness increases, the unit weight will increase, which will decrease transportability and workability. Therefore, it is more preferable that the thickness of the waterproof sheet is set to a value within the range of 1 to 10 mm, and even more preferable that it is set to a value within the range of 1.5 to 5 mm. In order for such waterproof sheets to satisfy the above-mentioned management guidelines, it is considered preferable for the thickness of the waterproof sheet to be 1.5 mm or more.

[0065] (5) Water impermeability The waterproof sheet has a water impermeability of JIS Z0208:1976. 2 / hr) can be used as an index for evaluation. That is, the moisture permeability is set to 0.1 mg / m 2By setting the value to be equal to or less than 1 / hr, a waterproof sheet exhibiting good waterproofing properties can be obtained. The reason for this is that the moisture permeability is 0.1 mg / m 2 If the value exceeds this limit, the water impermeability may not be sufficient. On the other hand, if the moisture permeability is too small, the range of choices for raw materials becomes too narrow, or handling properties become poor, or production costs and the like increase, which may be economically disadvantageous. Therefore, the moisture permeability of the waterproof sheet is set to 0.0001 to 0.05 mg / m 2 / hr, and more preferably 0.001 to 0.01 mg / m 2 It is more preferable to set the value in the range of 1 / hr.

[0066] In addition, the waterproofing of the waterproof sheet is determined by the moisture permeability (g / m) that conforms to the above-mentioned management guidelines. 2 The hydraulic conductivity (cm / sec) obtained from the above formula (hr) can be used as an index for evaluation. In other words, the permeability coefficient is 1×10 -9 By setting the value to be equal to or less than cm / sec, a waterproof sheet that exhibits good waterproofing properties can be obtained. The reason for this is that the permeability coefficient is 1×10 -9 If the value exceeds 1.0 cm / sec, it may not be possible to achieve sufficient water impermeability. On the other hand, if the hydraulic conductivity is too small, the range of choices for raw materials becomes too narrow, or the production costs increase, which may be economically disadvantageous. Therefore, the permeability coefficient of the waterproof sheet is set to 1.0×10 -14 ~1.0×10 -9 It is more preferable to set the value within the range of 1.0×10 cm / sec. -13 ~1.0×10 -9 More preferably, the value is in the range of cm / sec.

[0067] Here, referring to FIG. 7, the relationship between the biomass ratio (%) of a waterproof sheet and the waterproofing property of the waterproof sheet will be described. That is, the horizontal axis of FIG. 7 shows the biomass ratio (%) of the waterproof sheet, and the vertical axis shows the evaluation value of the waterproof property based on the waterproof coefficient of the waterproof sheet. The water impermeability based on the water barrier coefficient was evaluated according to the criteria shown in Example 1, and the water impermeability evaluation value (relative value) was calculated with ◎ being 5 points, ○ being 3 points, △ being 1 point, and × being 0 point. As shown by the characteristic curve in FIG. 7, it is clear that sufficient water impermeability can be obtained even with a waterproof sheet containing polyolefin derived from plant raw materials.

[0068] (6) Elastic modulus (1% secant elastic modulus) The waterproof sheet has a 1% secant elastic modulus of 110 to 300 N / mm at 23°C calculated in accordance with JIS K7127:1999. 2 It is preferable to set the value within the range. The reason for this is that the 1% secant elastic modulus of such a waterproof sheet is 110N / mm 2 If the value is less than this, the waterproof sheet becomes flexible and may become weak against impact. Conversely, 300N / mm 2 If the value exceeds this value, the waterproof sheet may be less able to conform to the surface on which it is laid. Therefore, the 1% secant elastic modulus of the waterproof sheet is set to 135 to 290 N / mm 2 It is more preferable to set the value within the range of 150 to 280 N / mm 2 It is more preferable that the value is within the range of .

[0069] Here, referring to FIG. 8, the relationship between the biomass ratio (%) of the waterproof sheet and the evaluation (relative value) of the elastic modulus of the waterproof sheet will be described. That is, the horizontal axis of FIG. 8 indicates the biomass ratio (%) of the waterproof sheet, and the vertical axis indicates the evaluated value (relative value) of the 1% secant elastic modulus of the waterproof sheet. The 1% secant elastic modulus was evaluated according to the criteria shown in Example 1, with ◎ being given 5 points, ◯ being given 3 points, △ being given 1 point, and × being given 0 point, and the evaluation value (relative value) of the 1% secant elastic modulus was calculated. As shown by the characteristic curve in Figure 8, in the range of 0 to 40% biomass content (%) of the waterproof sheet, there is a tendency for the evaluated value of the 1% secant elastic modulus of the waterproof sheet to increase rapidly as the biomass content (%) increases. Furthermore, it can be seen that in the range where the biomass ratio (%) of the waterproof sheet is greater than 40%, the evaluation results of the 1% secant elastic modulus do not change regardless of the biomass ratio (%). Therefore, by limiting the biomass ratio (%) of the waterproof sheet to a value within a predetermined range, it is possible to obtain a waterproof sheet whose 1% secant elastic modulus is within a predetermined range. The elastic modulus (1% secant elastic modulus) is expected to vary depending on the ambient temperature, for example, between room temperature (23° C.) and 0° C., and is known to vary with a certain correlation. If this is the case, there is no doubt that the 1% secant elastic modulus at different ambient temperatures can be adjusted by limiting the biomass content (%) of the waterproof sheet to a value within a specified range.

[0070] On the other hand, taking into consideration safety such as temperature drop, it is preferable to set the 1% secant elastic modulus at 0° C. to a value within a prescribed range in accordance with the Handbook for Waterproofing Systems for Final Waste Disposal Sites. More specifically, the waterproof sheet has a 1% secant elastic modulus of 150 to 350 N / mm at 0°C in accordance with JIS K7127:1999. 2 It is preferable to set the value within the range. The reason for this is that the 1% secant elastic modulus of such a waterproof sheet is 150N / mm 2 This is because the strength may be weak if the value is less than this. Conversely, 350N / mm 2 If the value exceeds this, the stiffness becomes excessively large and handling may become difficult. Therefore, the 1% secant elastic modulus of the waterproof sheet is set to 180 to 250 N / mm 2 It is more preferable to set the value within the range of 200 to 240 N / mm 2 It is more preferable that the value is within the range of . Furthermore, by setting the 1% secant elastic modulus of the waterproof sheet to a value within this range, it not only has excellent mechanical properties, but it also makes it easy to precisely adjust the tensile strength of the waterproof sheet and the tension of the waterproof sheet when installed on a slope within a specified range.

[0071] (7) Tear strength It is preferable that the tear strength of the waterproof sheet, measured in accordance with JIS K6252-1:2015, is set to a value within the range of 1180 to 1400 N / cm. The reason for this is that if the tear strength of such a waterproof sheet is less than 1180 N / cm, if the waterproof sheet is damaged, the damage will be more likely to spread, and the area that needs to be repaired may become larger. On the other hand, if the tear strength exceeds 1400 N / cm, the handling property may decrease and the selection range of the types of usable olefin resin compositions may become excessively narrow. Therefore, it is more preferable that the tear strength of the waterproof sheet is set to a value within the range of 1200 to 1300 N / cm, and even more preferable that it is set to a value within the range of 1220 to 1250 N / cm.

[0072] Here, referring to FIG. 9, the relationship between the biomass ratio (%) of a waterproof sheet and the tear strength of the waterproof sheet will be described. That is, the horizontal axis of FIG. 9 indicates the biomass ratio (%) of the waterproof sheet, and the vertical axis indicates the tear strength of the waterproof sheet. As shown by the characteristic curve in Figure 9, there is a clear tendency for the tear strength of the waterproof sheet to increase as the biomass ratio (%) of the waterproof sheet increases, up to around 0 to 40%. Furthermore, when the biomass content (%) of the waterproof sheet exceeds 40%, there is a tendency for the tear strength value of the waterproof sheet to increase slightly as the biomass content increases. Conversely, it can be said that the lower the biomass content (%) of the waterproof sheet, the smaller the tear strength value of the waterproof sheet can be. In any case, by limiting the biomass content (%) of the waterproof sheet to a value within a predetermined range, it is possible to obtain a waterproof sheet having a predetermined tear strength.

[0073] (9)Fixing work In addition, according to the Waste Final Disposal Site Waterproofing System Handbook, it is known that when laying a waterproof sheet on a slope, the waterproof sheet and weights such as concrete, called anchoring works, are poured into rectangular grooves at the step and top end of the slope at the site to fix the waterproof sheet in place. At this time, it is known that the size of the fixing work is calculated from the tension T1 (N / m) due to the weight of the waterproof sheet acting in the downward direction of the slope, the thermal stress T2 (N / m) due to the thermal contraction of the waterproof sheet due to temperature change, the first pull-in force T3-1 (N / m) due to compression by the load of the cargo on the waterproof sheet, and the second pull-in force T3-2 (N / m) due to compression by the increased load of heavy machinery etc. working on the cargo. In other words, the anchorage size (m) can be calculated from the following formula (3) as the size of the anchorage having a weight equal to the total tension (N / m) of the waterproof sheet. The size of the fixed work is defined as the length of one side of a square shape formed by cutting the fixed work with a width of 1m along a vertical plane along the width direction.

[0074]

number

[0075] Specifically, the size of the anchorage is determined by making the anchorage out of a concrete block (specific gravity: 23 kN / m 3 ) is preferably 0.7m or less. The reason for this is that by using such a size of the fixture, the size of the fixture can be directly understood, and thus the size of the fixture can be more easily reduced. Therefore, it is more preferable to set the fixing size to 0.65 m or less, and even more preferable to set it to 0.63 m or less. On the other hand, if the fixing work is too small, the influence of factors other than the overall tension of the waterproof sheet will become greater, and problems such as slippage may occur. Therefore, the fixing work size is preferably 0.3 m or more, more preferably 0.35 m or more, and even more preferably 0.4 m or more. The method for determining the size of the fixings will be described in detail below.

[0076] First, the total tension (N / m) of the waterproof sheet acting on the fixing work can be calculated from the following formula (3-1) by multiplying each of the values ​​of T1, T2, T3-1, and T3-2 by a predetermined influence rate.

[0077]

number

[0078] Furthermore, T1 is the tension of the waterproof sheet per 1 m width acting on the fixed structure due to the weight of the waterproof sheet acting in the downward direction of the slope. Specifically, T1 (N / m) can be calculated from the weight W1 (N / m) of the waterproof sheet per 1 m width, the friction coefficient μ1 between the waterproof sheet and the component directly below the waterproof sheet, and the inclination angle θ (°) of the slope, using the following formula (3-2).

[0079]

number

[0080] Therefore, T1 is preferably 300 N / m or less, more preferably 200 N / m or less, and even more preferably 100 N / m or less. When T1 is a negative value, no tension is applied, so T1 is set to 0 in the calculation.

[0081] In addition, T2 is the tension equivalent to the thermal stress of the waterproof sheet per meter width that acts on the fixing structure due to thermal contraction of the waterproof sheet caused by temperature change. Specifically, T2 (N / m) can be calculated from the following formula (4) relating to the thermal stress mentioned above.

[0082]

number

[0083] The reason for this is that by calculating the thermal stress (T2) of the waterproof sheet and specifically limiting it, the occurrence of thermal stress in the fixing work can be suppressed, and ultimately, its size and weight can be reduced. Therefore, as described above, the thermal stress (T2) is preferably set to a value within the range of 1000 to 10000 N / m, more preferably set to a value within the range of 1300 to 8000 N / m, and even more preferably set to a value within the range of 1500 to 7000 N / m.

[0084] In addition, the minimum air temperature tb used when calculating the thermal stress T2 of the waterproof sheet is basically preferably set according to the air temperature in the area where it will be used, but it is usually preferable to set it to a value within the range of -45 to 5°C. The reason for this is that by calculating the thermal stress T2 of the waterproof sheet based on such minimum temperatures, it becomes easier to provide waterproof sheets with safe and reliable fixing works that are suitable for each region of Japan (e.g., Tokyo, Sapporo, Okinawa), even taking into account the drop in winter temperatures due to recent environmental changes. Therefore, the waterproof sheet is preferably configured for use in areas with a minimum air temperature tb of -45 to 5°C, more preferably configured for use in areas with a minimum air temperature tb of -30 to 0°C, and even more preferably configured for use in areas with a minimum air temperature tb of -20 to -5°C.

[0085] In addition, the maximum temperature ta used when calculating the thermal stress T2 of the waterproof sheet is basically preferably set according to the temperature in the area where it will be used, but it is usually preferable to set it to a value within the range of 30 to 50°C. The reason for this is that by calculating the thermal stress T2 of the waterproof sheet based on such maximum temperatures, it becomes easy to provide a waterproof sheet with fixing works that is suitable for any part of Japan (e.g., Tokyo, Sapporo, Okinawa), even taking into account the rise in summer temperatures due to recent environmental changes. Therefore, the waterproof sheet is preferably configured for use in areas with a maximum temperature ta of 30 to 50°C, more preferably for use in areas with a maximum temperature ta of 33 to 48°C, and even more preferably for use in areas with a maximum temperature ta of 35 to 45°C.

[0086] In addition, the cross-sectional area A (m 2 ) can be calculated by multiplying the thickness (m) measured in accordance with JIS K6250:2019 by the width (m) of the waterproof sheet. Specifically, the cross-sectional area of ​​a waterproof sheet is usually 0.0003 to 0.01 m when the width is 1 m. 2 It is preferable to set the value within the range. The reason for this is that by using such a cross-sectional area, the thermal stress T2 can be calculated more accurately, and therefore the fixing size can be adjusted more accurately. Therefore, the cross-sectional area A of the waterproof sheet is set to 0.0004 to 0.005 m 2 It is more preferable to set the value within the range of 0.0005 to 0.0025 m 2 It is more preferable that the value is within the range of .

[0087] In addition, the temperature dependence exponent α of the elastic modulus of the waterproof sheet used when calculating the thermal stress T2 of the waterproof sheet can be obtained from the relationship between the elastic modulus measured under five different temperature environments, namely -25°C, 0°C, 20°C, 40°C, and 60°C, in a tensile test using dumbbell-shaped test pieces and rectangular test pieces in accordance with JIS K7139:2009. Specifically, it is usually preferable that the temperature dependence exponent α of the elastic modulus of the waterproof sheet is set to a value within the range of 0.003 to 0.03. The reason for this is that by using such a temperature-dependent index, the waterproof sheet can be used more generally, regardless of the temperature, etc. of the place where it is used. Therefore, it is more preferable that the temperature dependence exponent α of the elastic modulus of the waterproof sheet is set to a value within the range of 0.005 to 0.02, and even more preferably within the range of 0.008 to 0.015. Here, as an example, the temperature dependence index α is based on the material of the waterproof sheet, and is as follows: EPDM: approximately 0.01, PE (including thermoplastic elastomer): approximately 0.013, PP (including thermoplastic elastomer): approximately 0.013, HDPE: approximately 0.01, PVC: approximately 0.034, and TPU: approximately 0.0056.

[0088] Furthermore, the linear expansion coefficient β (1 / ° C.) of the waterproof sheet used in calculating the thermal stress T2 of the waterproof sheet can be determined by a thermal expansion coefficient test in accordance with JIS K7197:1991. Specifically, the linear expansion coefficient β of the waterproof sheet is usually set to 0.1×10 -4 ~3×10 -4 It is preferable to set the temperature within the range of 1 / °C. The reason for this is that by using such a linear expansion coefficient, the waterproof sheet can be used more generally, regardless of the temperature and other conditions of the location where it is used. Therefore, the linear expansion coefficient β of the waterproof sheet is set to 0.4×10 -4 ~2.5×10 -4 It is more preferable to set the value within the range of 0.8×10 -4 ~2×10 -4 It is more preferable that the value is within the range of .

[0089] The number n of waterproof sheets is preferably selected appropriately depending on the application of the waterproof sheets and the installation location, but is usually preferably two or more. The reason for this is that by using this number of sheets, even if a hole is caused in the upper layer of waterproof sheet by a sharp cargo or the like, it is possible for the layer below to maintain a specified waterproof effect. Therefore, the number of waterproof sheets is more preferably 2 to 10 sheets, and even more preferably 3 to 5 sheets. Depending on the type of substrate, it may be preferable to use only one sheet. Therefore, although two waterproof sheets will basically provide sufficient waterproofing, taking into account the possibility of them being torn, it is more preferable to use 2 to 10 sheets, and even more preferable to use 3 to 5 sheets.

[0090] In addition, T3-1 is the tension equivalent to the pulling force of the waterproof sheet per meter width (hereinafter sometimes referred to as the first pulling force) acting on the fixing work due to compression by the load of the cargo on the waterproof sheet. In other words, T3-1 is the tension equivalent to the retraction force of the waterproof sheet that acts on the fixing structure when the waterproof sheet is compressed by placing waste or other load on it and the surrounding parts pull back the compressed part. Here, although there are various methods for calculating T3-1, it has been found that in any case, the difference in the calculation method has almost no effect on the calculation of the fixed work size. For example, T3-1 (N / m) can be calculated from the weight of the load per 1 m width W2 (N / m), the friction coefficient μ2 between the waterproof sheet and the component directly below the waterproof sheet, the inclination angle θ (°) of the slope, and the angle δ (°) between the waterproof sheet and the load, using the following formula (3-3):

[0091]

number

[0092] Therefore, the first retraction force T3-1 is preferably set to a value within the range of 5000 to 15000 N / m, more preferably to a value within the range of 6000 to 12000 N / m, and even more preferably to a value within the range of 7000 to 10000 N / m. Here, δ is the angle between the waterproof sheet and the cargo. Since cargo such as waste is dumped along the slope, this angle is very small, and therefore tan δ can be calculated as essentially 0.

[0093] Here, it is known that even if the same load is applied to the second, third and subsequent layers from the surface of the waterproof sheet, the pulling force generated by the load gradually decreases. Therefore, when a waterproof sheet is made up of multiple layers, it is preferable to multiply the burden rate of the lower layer by 0.3 to 0.6 in the calculation. Therefore, as an example, it is preferable to set the burden rate of the second layer to 0.45, and the burden rate of the third layer and thereafter to 0.3.

[0094] In addition, T3-2 is the tension equivalent to the pulling force of the waterproof sheet per meter of width (hereinafter sometimes referred to as the second pulling force) acting on the fixing work due to compression by the weight of the heavy equipment on the load. In other words, T3-2 is the tension equivalent to the retraction force of the waterproof sheet acting on the fixed work when the waterproof sheet is compressed due to the approach of heavy machinery such as a bulldozer working on a load, and the surrounding parts pull back the compressed part. Here, although there are various methods for calculating T3-2, it has been found that in any case, differences in the calculation method have almost no effect on the calculation of the fixed work size. For example, T3-2 (N / m) can be calculated from the weight of the load per 1 m width W3 (N / m), the friction coefficient μ3 between the waterproof sheet and the component directly below the waterproof sheet, the inclination angle θ (°) of the slope, and the angle δ (°) between the waterproof sheet and the load, using the following formula (3-4):

[0095]

number

[0096] Therefore, the second retraction force T3-2 is preferably set to a value within the range of 500 to 3000 N / m, more preferably to a value within the range of 800 to 2500 N / m, and further preferably to a value within the range of 1000 to 2000 N / m. Here, δ is the angle between the waterproof sheet and the cargo. Since cargo such as waste is dumped along the slope, this angle is very small, and therefore tan δ can be calculated as essentially 0.

[0097] [Second embodiment] The second embodiment is a method for producing a waterproof sheet, including the following steps (1) and (2). Step (1): A step of mixing an olefin resin composition containing, as a component (A), a first polyolefin resin containing petroleum-derived ethylene units and, as a component (B), a second polyolefin resin containing plant-derived ethylene units, or preparing an olefin resin composition that is substantially free of component (A) and contains, as a component (B), a polyolefin resin containing plant-derived ethylene units alone, and adjusting the biomass degree in accordance with ASTM D6866 to a value within a range of more than 40% to 100%. Step (2): A step of forming a waterproof sheet derived from an olefin resin composition, and setting the tensile elongation of the waterproof sheet in accordance with JIS K6251:2017 to a value of 650 to 1200% or more. Hereinafter, the method for producing the waterproof sheet of the second embodiment will be specifically described with reference to the drawings as appropriate.

[0098] 1.Process (1) (1) Step (1) is a step of preparing a specified olefin resin composition. That is, an olefin resin composition containing, as component (A), a first polyolefin resin containing petroleum-derived ethylene units and, as component (B), a second polyolefin resin containing plant-derived ethylene units, or an olefin resin composition substantially free of component (A) and containing, as component (B), only a polyolefin resin containing plant-derived ethylene units, is prepared by manufacturing the composition or purchasing a commercially available product. Next, these raw material resins and the like are weighed and then mixed in a predetermined ratio, and the biomass degree according to ASTM D6866 is adjusted to a value within the range of more than 40% to 100%. The details of the first polyolefin resin containing petroleum-derived ethylene units as component (A) and the second polyolefin resin containing plant-derived ethylene units as component (B) can be the same as those described in the first embodiment, and therefore will not be described again.

[0099] (2) In addition, in step (1), when a reinforcing material is contained as component (C) when the total amount of the olefin resin composition is taken as 100% by weight, the amount of the reinforcing material is preferably within a range of 0.1 to 30% by weight. The reason for this is that by blending a specified amount of reinforcing material in this manner, the weather resistance and mechanical properties of the waterproof sheet can be further improved, and it can also be made easier to adjust them to within a specified range. In addition, by blending a predetermined amount of such reinforcing material, it becomes easy to color the resulting waterproof sheet black or gray, which may improve the decorativeness, light-shielding properties, etc. of the waterproof sheet.

[0100] 2.Process (2) Step (2) is a step of forming a waterproof sheet of a predetermined thickness from a predetermined olefin resin composition. That is, it is a process of forming a predetermined waterproof sheet by at least one of known film-forming methods such as an extruder, a film forming machine, a T-die extruder, a press device, a casting method, and an inflation molding machine.

[0101] 3. Other processes (1) Inspection process for waterproofing of waterproof sheets The resulting waterproof sheet was measured for moisture permeability (g / m2), which is an index of waterproofing, in accordance with JIS Z0208:1976. 2 It is preferable to include a step of measuring the moisture permeability (hr) of the sample, calculating the water permeability coefficient k (cm / sec) from the moisture permeability by a method described later, and inspecting whether the water permeability coefficient is within a predetermined range. That is, for the obtained waterproof sheet, the permeability coefficient is, for example, 1 × 10 -9It is preferable to confirm that the value is equal to or less than cm / sec. In addition to or instead of the hydraulic conductivity, which is an index of water impermeability, the moisture permeability can also be used as an index of water impermeability.

[0102] (2) Winding and cutting process of waterproof sheet When the obtained waterproof sheet is in a long shape, it is preferable to include a step of winding it up into a roll. It is also preferable to include a cutting step of punching out the obtained waterproof sheet into a predetermined shape. In addition, the direction in which the waterproof sheet is wound up by the winding machine is sometimes referred to as the longitudinal direction, and the direction perpendicular to the longitudinal direction is sometimes referred to as the width direction.

[0103] (3) Evaluation process for the mechanical properties of the waterproof sheet It is preferable to include a step of evaluating the mechanical properties of the obtained waterproof sheet. That is, it is preferable to measure the tensile elongation of the obtained waterproof sheet in accordance with JIS K6251:2017 and confirm that it is a value within the range of, for example, 650 to 1200%, and then evaluate it. In addition, it is preferable to measure the bending resistance of the obtained waterproof sheet in accordance with JIS L1096:2010 and confirm that the bending resistance is within a range of, for example, 205 to 500 mN.

[0104] (4) Lamination process of other sheets The obtained waterproof sheet may include a lamination step for processing the front and back surfaces thereof. That is, for example, it is possible to laminate the obtained waterproof sheet and sheets of the same or different types using heat welding, adhesives, etc. to form a waterproof sheet of a multi-layer structure. It is also preferable to laminate the resulting waterproof sheet with other resin layers, metal layers, ceramic layers, nonwoven fabrics, or wood using an adhesive or the like to form a multilayer structure.

[0105] (5) Evaluation process for thermal stress of waterproof sheet It is preferable to include a step of evaluating the thermal stress T2 of the obtained waterproof sheet. That is, it is preferable to confirm and evaluate that the thermal stress T2 calculated by the formula (4) is within the range of 1000 to 10000 N / m. The reason for this is that by calculating the thermal stress (T2) of the waterproof sheet and specifically limiting it, the occurrence of thermal stress in the fixing work can be suppressed, and ultimately, its size and weight can be reduced. Therefore, it is more preferable that the thermal stress (T2) of the waterproof sheet is set to a value within the range of 1300 to 8000 N / m, and even more preferable that it is set to a value within the range of 1500 to 7000 N / m.

[0106] (6) Installation process of anchoring works In addition, it is preferable to include a post-process of casting fixings at a predetermined location, such as a waste disposal site. Specifically, a slope and a rectangular groove for the fixing work are formed at a predetermined location. Next, a member called a waterproofing work consisting of the obtained waterproof sheet and protective mat is laid on the slope, and it is preferable to fix the waterproof sheet in place by pouring a weight such as concrete into the rectangular trench. EXAMPLES

[0107] The present invention will now be described in more detail with reference to examples.

[0108] [Example 1] 1. Manufacturing of waterproof sheets (1) Preparation of Olefin Resin Composition As the component (A), a first polyolefin resin containing petroleum-derived ethylene units (commercially available product: Evolue SP1022 (density: 0.905 to 0.912 g / cm), manufactured by Prime Polymer Co., Ltd.) 3 , MFR: 1.5 to 2.5 g / 10 min (190° C., 2.16 kg load), melting points: 97° C., 113.6° C., biomass ratio: 0%, resin color: colorless and transparent, referred to as TYP1 in Table 1) was prepared.

[0109] Similarly, as component (B), a second polyolefin resin containing plant-derived ethylene units (commercially available product: SLH218 (density: 0.916 g / cm) manufactured by Braskems) was used. 3 , comonomer: 1-hexene, MFR: 2.3 g / 10 min (190° C., 2.16 kg load), melting point: 126° C., biomass content: 84%, resin color: colorless and transparent, referred to as TYP2 in Table 1) was prepared.

[0110] Next, the components (A) and (B) were weighed and mixed in a ratio of 50:50 by weight so that the biomass content of the olefin resin composition would be 42.0%. Furthermore, a carbon black-containing masterbatch (Tokyo Ink & Chemicals, Inc., PEX 9BB047 BLACK, average particle size 10-300 nm, carbon black concentration 40%) was uniformly blended to a concentration of 6.7% by weight relative to the total amount of the olefin resin composition (100% by weight) to obtain a specified olefin resin composition.

[0111] (2) Formation of waterproof sheet Using a T-die coater (discharge temperature 200°C, pressure: 6kg / cm 2 ) and using the prepared olefin resin composition as a raw material, a long sheet (single layer) having an average thickness of 1.5 mm was manufactured.

[0112] 2.Evaluation of waterproof sheets (1) Water impermeability (rating 1) The moisture permeability, which is an index of water impermeability, of the obtained waterproof sheet was measured in accordance with JIS Z0208:1976, and the water permeability coefficient k (cm / sec) was calculated using the following formula (1). The sheet was evaluated according to the following criteria.

[0113]

number

[0114] ◎: Permeability coefficient is 1×10 -12 The value is less than cm / sec. ○: Permeability coefficient is 1×10 -12 ~1×10-11 The value is less than cm / sec. △: Permeability coefficient is 1×10 -11 ~1×10 -9 The value is less than cm / sec. ×: Permeability coefficient is 1×10 -9 The value is greater than or equal to cm / sec.

[0115] (2) Tensile elongation (rating 2) In accordance with JIS K6251:2017, a No. 3 dumbbell test piece was used to punch out the waterproof sheet three times in each of the longitudinal and transverse directions to obtain waterproof sheet test pieces. The gauge length until the test piece broke was measured at a tensile speed of 50 mm / min, a chuck distance of 60 mm, and room temperature (23°C), and the tensile elongation of the waterproof sheet was calculated using the following formula. The average of the calculated tensile elongation in the longitudinal and transverse directions was taken as the tensile elongation of the waterproof sheet. E B ={(L1-L0) / L0}×100 E B : Tensile elongation (unit: %) L0: Gauge line distance (20mm) L1: Gauge distance when cutting (unit: mm) Tensile elongation = (average value of tensile elongation in the longitudinal direction + average value of tensile elongation in the transverse direction) / 2

[0116] (3) Bending resistance (rating 3) According to the Gurley method specified in JIS L1096:2010, six test pieces, each 89 mm long and 25 mm wide, were prepared in the longitudinal direction of the waterproof sheet. Of the test pieces obtained, the bending resistance (mN) of three of the front surfaces and the other three of the back surfaces were measured at room temperature (23°C). The average bending resistance of the front and back surfaces was taken as the bending resistance (mN) of the waterproof sheet.

[0117] (4) Environmental characteristics (rating 4) When the CO2 emissions of component (A), the first polyolefin resin containing petroleum-derived ethylene units, are taken as 100%, the CO2 emissions of component (B), the second polyolefin resin containing plant-derived ethylene units, are 30%, and it has been found that the second polyolefin resin can reduce CO2 emissions by 70%. Therefore, it is possible to calculate the amount of CO2 emissions and the reduction rate from the weight ratio of component (A) and component (B), and when the ratio of component (A) is 50 parts by weight and component (B) is 50 parts by weight, it can be calculated that the CO2 emissions will be reduced by approximately 35%. The calculated values ​​were evaluated according to the following criteria. ◎: CO2 emissions reduction is 30% or more. ○: CO2 emissions reduction is 10% or more. △: CO2 emissions reduction is 5% or more. ×: The reduction in CO2 emissions is less than 5%.

[0118] (5) Elasticity (rating 5) A rectangular test piece (2.5 cm wide, 16 cm long) was prepared from the obtained waterproof sheet, and a tensile test was performed in the longitudinal direction in accordance with JIS K7127:1999 using a tensile tester (Strograph VG10E, manufactured by Toyo Seiki Seisakusho Co., Ltd.) at a tensile speed of 1 mm / min, a grip distance of 100 mm, and room temperature (23°C). At this time, the stress when 1% strain (chuck movement distance of 1 mm) was applied was calculated, and the 1% secant elastic modulus was calculated by dividing this value by the cross-sectional area and strain of the test piece, as shown in the following formula (2). The measurement was performed three times, and the average value was evaluated according to the following criteria.

[0119]

number

[0120] ◎: 150N / mm 2 This value is greater than or equal to the value above, making it extremely resistant to impacts. ○: 135N / mm 2 This value is above the limit, and the material is fairly resistant to impacts. △: 110N / mm 2 The above values ​​mean that there is no problem with use. ×:110N / mm 2 The value is less than this, making it vulnerable to impact.

[0121] (6) Tear strength (rating 6) From the obtained waterproof sheet, an angle-shaped test piece without a cut was prepared in accordance with JIS K6252-1:2015, and a tear test was carried out in the longitudinal and transverse directions using a tear tester (Strograph VG10E, manufactured by Toyo Seiki Seisakusho) at a tensile speed of 50 mm / min and a chuck distance of 60 mm. The measurement was carried out three times, and the average value was taken as the tear strength value (N / cm) of the waterproof sheet.

[0122] [Example 2] In Example 2, a waterproof sheet was manufactured and evaluated in the same manner as in Example 1, except that no petroleum-derived first polyolefin resin was used as component (A), and only a plant-derived second polyolefin resin (TYP2) containing ethylene units was used as component (B), and the biomass content of the olefin resin composition was 84.0%.

[0123] [Example 3] In Example 3, the petroleum-derived first polyolefin resin as component (A) was Evolu SP2020 (density: 0.916 g / cm) manufactured by Prime Polymer Co., Ltd. 3 , MFR: 23 g / 10 min, resin color: colorless and transparent, referred to as TYP3 in Table 1.) was used, and a waterproof sheet was produced and evaluated in the same manner as in Example 1.

[0124] [Example 4] In Example 4, a first polyolefin resin (TYP3) containing petroleum-derived ethylene units as component (A) and a second polyolefin resin (TYP2) containing plant-derived ethylene units as component (B) were used in a blending ratio of 30:70, and the biomass content of the olefin resin composition was 58.8%. Except for this, waterproof sheets were manufactured and evaluated in the same manner as in Example 1.

[0125] [Example 5] In Example 5, a first polyolefin resin (TYP3) containing petroleum-derived ethylene units as component (A) and a second polyolefin resin (TYP2) containing plant-derived ethylene units as component (B) were used in a blending ratio of 20:80, and the biomass content of the olefin resin composition was 67.2%. Except for this, waterproof sheets were manufactured and evaluated in the same manner as in Example 1.

[0126] [Comparative Example 1] In Comparative Example 1, a waterproof sheet was produced and evaluated in the same manner as in Example 1, except that only the petroleum-derived first polyolefin resin (TYP1) was used as the component (A).

[0127] [Comparative Example 2] In Comparative Example 2, a waterproof sheet was manufactured and evaluated in the same manner as in Example 1, except that the blending ratio of the petroleum-derived first polyolefin resin (TYP1) to the plant-derived second polyolefin resin (TYP2) containing ethylene units was 90:10, by weight, and the biomass content of the olefin resin composition was 8.4%.

[0128] [Comparative Examples 3 to 4] In Comparative Examples 3 and 4, a first polyolefin resin (TYP1) containing petroleum-derived ethylene units and a second polyolefin resin (TYP3) also containing petroleum-derived ethylene units were used as component (A), and the blending ratios thereof were 70:30 and 50:50, respectively. Except for this, waterproof sheets were manufactured and evaluated in the same manner as in Example 1.

[0129] [Table 1] [Industrial Applicability]

[0130] According to the water-proof sheet and its manufacturing method of the present invention, an olefin resin composition is used which contains, as component (A), a first polyolefin resin containing petroleum-derived ethylene units, and as component (B), a second polyolefin resin containing plant-derived ethylene units. By setting the biomass degree of the olefin resin composition to a value within a predetermined range and setting the tensile elongation rate, etc. to values ​​within predetermined ranges, it is possible to obtain excellent environmental properties and mechanical properties such as tensile elongation.

[0131] Similarly, by using a waterproof sheet derived from an olefin resin composition that does not contain component (A) and contains, as component (B), only a polyolefin resin containing plant-derived ethylene units, and by setting the biomass degree of the olefin resin composition to a value within a specified range and setting the tensile elongation rate, etc. to values ​​within specified ranges, it is possible to obtain excellent environmental characteristics and mechanical characteristics such as tensile elongation.

[0132] Moreover, it was confirmed that even if no reinforcing material is added, or even if the type and amount of reinforcing material is changed within a specified range, the values ​​and evaluation values ​​of water impermeability, biomass content, tensile elongation, bending resistance, environmental characteristics, and elastic modulus are almost unchanged.

[0133] Therefore, the waterproof sheets of the present invention are expected to be used in a wide range of applications, not only as waterproof sheets used in waste industrial disposal sites and the like, but also as spring water blocking sheets used in removing spring water in tunnel construction and dam sites, rainwater infiltration prevention sheets used on the roofs of buildings and houses, general waterproof sheets, and even bag-shaped products obtained from them. [Explanation of symbols]

[0134] 10, 10′: Water-resistant sheet 10a: Carbon black 10b: Olefin resin 12: Waste 14: Waste disposal site development 16: Fixed work 22, 22′: Joint 24, 24´: Different types of waterproof sheets 24a: Pigment 24b: First olefin resin 30: Homogeneous multilayer structure 32: Heterogeneous multilayer structure 34: Multi-layer sandwich structure

Claims

1. As a component (A), a first polyolefin resin containing a petroleum-derived ethylene unit; As a component (B), a second polyolefin resin containing a plant-derived ethylene unit; A waterproof sheet derived from an olefin resin composition comprising: Any of the waterproof sheets derived from an olefin resin composition that does not contain the component (A) and contains, as the component (B), a plant-derived polyolefin resin containing an ethylene unit alone, The biomass degree of the olefin resin composition according to ASTM D6866 is set to a value within a range of more than 40% to 100%, The waterproof sheet is characterized in that the average tensile elongation in the longitudinal direction and width direction is within the range of 650 to 1200% in accordance with JIS K6251:2017.

2. A waterproof sheet as described in claim 1, characterized in that it contains a reinforcing material as component (C) when the total amount of the olefin resin composition is 100% by weight, and the amount of the reinforcing material is within the range of 0.1 to 30% by weight.

3. 3. The waterproof sheet according to claim 1, wherein the component (A) is a copolymer of petroleum-derived ethylene and an α-olefin having 3 to 12 carbon atoms.

4. 3. The waterproof sheet according to claim 1, wherein the component (B) is a copolymer of plant-derived ethylene and an α-olefin having 3 to 12 carbon atoms.

5. The waterproof sheet according to claim 1 or 2, characterized in that the bending resistance in accordance with JIS L1096:2010 is set to a value within the range of 205 to 500 mN.

6. 3. The waterproof sheet according to claim 1, characterized in that the thickness is within a range of 0.5 to 30 mm.

7. A method for producing a waterproof sheet, comprising the following steps (1) and (2): Step (1): Mixing an olefin resin composition containing, as a component (A), a first polyolefin resin containing a petroleum-derived ethylene unit and, as a component (B), a second polyolefin resin containing a plant-derived ethylene unit, or preparing an olefin resin composition that does not contain the component (A) and contains, as the component (B), only a polyolefin resin containing a plant-derived ethylene unit; A step of setting the biomass degree in accordance with ASTM D6866 to a value in the range of more than 40% to 100%. Step (2): forming a waterproof sheet derived from the olefin resin composition, and setting the average tensile elongation of the waterproof sheet in the longitudinal direction and the width direction to a value of 650 to 1200% or more in accordance with JIS K6251:2017.

8. A method for producing a waterproof sheet as described in claim 7, characterized in that in step (1), when the total amount of the olefin resin composition is 100% by weight, a reinforcing material is included as component (C), and the blending amount of the reinforcing material is within the range of 0.1 to 30% by weight.

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