KR102596389B1 - Multilayer polypropylene-based film - Google Patents

Abstract

According to an embodiment of the present invention, a multilayer polypropylene-based film is provided. The multilayer polypropylene-based film sequentially includes a corona layer, a core layer, and a sealant layer, the core layer includes a first core layer and a second core layer, and the sealant layer includes a first sealant layer and a second sealant layer. It may include a sealant layer.

Description

Multilayer polypropylene-based film {MULTILAYER POLYPROPYLENE-BASED FILM}

The present invention relates to a multilayer polypropylene-based film, and specifically relates to a multilayer polypropylene-based film consisting of a total of 5 layers: a corona layer, a first core layer, a second core layer, a first sealant layer, and a second sealant layer. will be.

Cell pouches for secondary batteries are made by gluing several layers of film together, and are made into a pouch shape to protect the battery cells, including the anode, cathode, and separator. These battery cells are mainly used in medium to large-sized batteries such as electric vehicles and ESS (Energy Storage Systems). Therefore, cell pouch film for manufacturing cell pouches for secondary batteries is one of the key materials that are very important in ensuring the safety of secondary batteries. do. Specifically, in the case of cell pouch films for secondary batteries, various sealing properties such as heat resistance, moisture resistance, electrolysis resistance, impact resistance, and corrosion prevention are essential, and stable physical properties are required to protect the secondary battery inside.

However, in the case of conventional cell pouch films for secondary batteries, polypropylene-based films to which polyimide-based slip agents have been added have been applied. In this case, when attempting to adhere polypropylene-based films to other films to manufacture cell pouches for secondary batteries, , there was a problem that the sealing properties were deteriorated and the physical properties were deteriorated due to poor adhesion between layers. Therefore, research is needed to solve these shortcomings and improve the physical properties of the film.

The present invention is intended to solve the above problems, and has a five-layer structure of a corona layer, a first core layer, a second core layer, a first sealant layer, and a second sealant layer, thereby providing improved physical properties and sealing characteristics. The purpose is to provide a multilayer polypropylene-based film.

The technical problems of the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below.

According to an embodiment of the present invention, a multilayer polypropylene-based film is provided. The multilayer polypropylene-based film sequentially includes a corona layer, a core layer, and a sealant layer, the core layer includes a first core layer and a second core layer, and the sealant layer includes a first sealant layer and a second sealant layer. It may include a sealant layer.

Additionally, the corona layer may include one or more alpha-olefin block copolymers; polybutene-1; and propylene-based elastomer.

In addition, the corona layer includes 50 to 70% by weight of the at least one alpha-olefin block copolymer; 10 to 30% by weight of polybutene-1; And it may include 10 to 30% by weight of the propylene-based elastomer.

In addition, the core layer includes one or more alpha-olefin block copolymers; polybutene-1; Styrene-based elastomer; and an amide-based slip agent.

Additionally, the styrene-based elastomer may include SEBS (Styrene-Ethylene/Butylene-Styrene Block Copolymer).

Additionally, the amide-based slip agent may include erucamide.

In addition, the first core layer contains 47 to 67% by weight of the at least one alpha-olefin block copolymer; 20 to 40% by weight of polybutene-1; 5 to 15% by weight of the styrene-based elastomer; And it may include 1 to 5% by weight of the amide-based slip agent.

In addition, the second core layer contains 40 to 60% by weight of the at least one alpha-olefin block copolymer; 20 to 40% by weight of polybutene-1; 5 to 15% by weight of the styrene-based elastomer; And it may include 5 to 15% by weight of the amide-based slip agent.

In addition, the sealant layer is an alpha-olefin random copolymer; Amide-based slip agent; Styrene-based elastomer; and propylene-based elastomer.

Additionally, the amide-based slip agent may include three types of erucamide, stearyl erucamide, and stearyl steramide.

In addition, the first sealant layer contains 60 to 80% by weight of the alpha-olefin random copolymer; 5 to 15% by weight of one type of amide-based slip agent; 5 to 15% by weight of the styrene-based elastomer; And it may include 5 to 15% by weight of the propylene-based elastomer.

In addition, the second sealant layer contains 70 to 90% by weight of the alpha-olefin random copolymer; 5 to 15% by weight of the two types of amide-based slip agents; And it may include 5 to 15% by weight of the propylene-based elastomer.

Additionally, the thickness ratio of the corona layer: the first core layer: the second core layer: the first sealant layer: the second sealant layer may be 15:15:40:15:15.

Additionally, the multilayer polypropylene-based film may have a dynamic friction coefficient of 0.05 to 0.09.

Additionally, the total thickness of the multilayer polypropylene-based film may be 40 to 120 micrometers.

According to an embodiment of the present invention, a cell pouch film for secondary batteries made from the multilayer polypropylene-based film is provided.

According to the present invention, the multilayer polypropylene-based film has a five-layer structure in which a corona layer, a first core layer, a second core layer, a first sealant layer, and a second sealant layer are sequentially stacked, so that the physical properties and sealing characteristics This overall improvement has the advantage of manufacturing a cell pouch for secondary batteries that can stably protect the internal battery.

In order to more fully understand the drawings cited in the detailed description of the present invention, a brief description of each drawing is provided.
1 is a cross-sectional view of a multilayer polypropylene-based film according to an embodiment of the present invention.
Figure 2 is a photograph of a sealing characteristic test of a multilayer polypropylene-based film according to an embodiment of the present invention.

Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by a person skilled in the art to which the present invention pertains. In general, the nomenclature used herein is well known and commonly used in the art. Additionally, when describing embodiments of the present invention, if detailed descriptions of related known configurations or functions are judged to impede understanding of the embodiments of the present invention, the detailed descriptions will be omitted. In addition, embodiments of the present invention will be described below, but the technical idea of the present invention is not limited or limited thereto and may be modified and implemented in various ways by those skilled in the art.

While researching to improve the physical properties of polypropylene-based films, the present inventors discovered that when the polypropylene-based film is composed of a multilayer polypropylene-based film consisting of a total of 5 layers, the overall physical properties of the film can be improved and the sealing properties of the film can be improved. It was confirmed that improvements could be made and the present invention was completed.

1 is a cross-sectional view of a multilayer polypropylene-based film according to an embodiment of the present invention.

Referring to FIG. 1, the multilayer polypropylene-based film 1000 may sequentially include a corona layer 100, a core layer 200, and a sealant layer 300. At this time, the core layer 200 may include a first core layer 210 and a second core layer 220, and the sealant layer 300 may include a first sealant layer 310 and a second sealant layer 320. It can be included. That is, the multilayer polypropylene-based film 1000 may be composed of a total of 5 layers.

The corona layer 100 is a layer applied to the inside and is subjected to corona treatment on the surface, so that hydrophilicity and coating characteristics can be improved, and adhesion can be improved when additionally adhering to another substrate.

Depending on the embodiment, the corona layer 100 is an alpha-olefin block copolymer (α-Olefin Block Copolymer); Polybutene-1; and propylene-based elastomer. At this time, one or more types of alpha-olefin block copolymers may be included, and preferably three types may be included.

The melt index of at least one alpha-olefin block copolymer is preferably 3.0 g/10 min to 5.0 g/10 min, and the density is preferably 0.90 g/cm ³ to 0.93 g/cm ³ , but is not limited thereto. In particular, the one or more types of alpha-olefin block copolymers may include three or more types of alpha-olefin block copolymers having different heat deflection temperatures (HDT), thereby forming a shell-like appearance on the surface of the coating film. It can suppress the orange peel phenomenon that causes irregularities. In the case of the three types of alpha-olefin block copolymers, the heat distortion temperature of the first alpha-olefin block copolymer is 98 ℃ to 108 ℃, and the heat distortion temperature of the second alpha-olefin block copolymer is 105 ℃ to 115 ℃, , It is preferable to use the third alpha-olefin block copolymer with a heat distortion temperature of 100 ℃ to 110 ℃ in terms of improving the physical properties of the film through optimal extrusion, but it is not limited to this. In addition, when one or more of the alpha-olefin block copolymers is used in a weight ratio of 3:1 to 3:1 to 3, the orange peel phenomenon is suppressed and the mechanical strength of the film is excellent. Depending on the embodiment, the alpha-olefin block copolymer may be a propylene-ethylene block copolymer.

Polybutene-1 is an additive that improves adhesive properties, and the melt index is preferably 1 g/10 min to 2 g/min and the density is preferably 0.8 g/cm ³ to 1.0 g/cm ³ , but is not limited thereto.

The propylene-based elastomer is intended to improve adhesive properties and may be a polymer containing propylene and ethylene. At this time, the content of ethylene is 8% by weight to 20% by weight, the melt index is 1.0 g/10min to 18.0 g/10min (more preferably, 1.0 g/10min to 5.0 g/10min), and the density is 0.86 g/cm. It is preferably ³ to 0.89 g/cm ³ , but is not limited thereto. Depending on the embodiment, the propylene-based elastomer may be a metallocene propylene-based elastomer manufactured using a metallocene catalyst.

Depending on the embodiment, the corona layer 100 includes 50 to 70% by weight of one or more alpha-olefin block copolymers relative to the total weight of the corona layer 100; 10 to 30% by weight of polybutene-1; And it may include 10 to 30% by weight of propylene-based elastomer. Also, preferably, the corona layer 100 may include 60% by weight of one or more types of propylene-ethylene block copolymer, 20% by weight of polybutene-1, and 20% by weight of metallocene propylene-based elastomer. Within the above range, the adhesive strength and heat resistance of the corona layer 100 can be optimized.

The core layer 200 is a layer applied in the middle, connects the corona layer 100 and the sealant layer 300, and can provide thickness to the multilayer polypropylene-based film 1000.

Depending on the embodiment, the core layer 200 may include an alpha-olefin block copolymer; polybutene-1; Styrene-based elastomer; and an amide-based slip agent. At this time, one or more types of alpha-olefin block copolymers may be included, and preferably three types may be included. Also, preferably, the alpha-olefin block copolymer may be a propylene-ethylene block copolymer. The alpha-olefin block copolymer and polybutene-1 of the core layer 200 can be described in the same way as the alpha-olefin block copolymer and polybutene-1 of the corona layer 100, and detailed descriptions are omitted.

Styrene-based elastomer is an additive added to improve the transparency and flexibility of polypropylene and improve the process, such as SEBS (Polystyrene-block-Poly(Ethylene/Butylene)-block-Polystyrene block copolymer), SEPS (Polystyreneb-poly( ethylene/propylene)-b-poystyrene), HSBR(Hydrogenated Styrene-Butadiene Rubber), SIBS(Poly(styrene-b-isobutylene-b-styrene)), SEEPS(Polystyrenebpoly(ethylene-ethylene/propylene)-b-poystyrene) and SIS (Styrene Isoprene Styrene Block Copolymer), preferably SEBS (Polystyrene-block-Poly(Ethylene/Butylene)-block-Polystyrene block copolymer), but is not limited thereto. .

Amide-based slip agents are additives added to improve the slip properties of films. For example, the amide-based slip agent may include at least one of Erucamide, Stearyl Erucamide, and Stearyl Steramide. At this time, it is desirable for the core layer 200 to contain erucamide in order to prevent whitening and tearing of the film.

Depending on the embodiment, when the core layer 200 includes a first core layer 210 and a second core layer 220, the first core layer 210 is the total weight of the first core layer 210. 47 to 67% by weight of one or more alpha-olefin block copolymers; 20 to 40% by weight of polybutene-1; 5 to 15% by weight of styrene-based elastomer; and 1 to 5% by weight of an amide-based slip agent, and the second core layer 220 includes 40 to 60% by weight of one or more alpha-olefin block copolymers relative to the total weight of the second core layer 220. ; 20 to 40% by weight of polybutene-1; 5 to 15% by weight of styrene-based elastomer; and 5 to 15% by weight of an amide-based slip agent. Also, preferably, the first core layer 210 contains 57% by weight of one or more propylene-ethylene block copolymers; 30% by weight of polybutene-1; SEBS 10% by weight; and 3% by weight of erucamide, and the second core layer 220 includes 50% by weight of one or more propylene-ethylene block copolymers; 30% by weight of polybutene-1; SEBS 10% by weight; and 10% by weight of erucamide. Within the above range, the sealing characteristics and physical properties of the core layer 200 can be optimized.

The sealant layer 300 is a layer applied to the outside, can be an object of adhesion to other films, and can serve as a coating layer.

Depending on the embodiment, the sealant layer 300 is made of alpha-olefin random copolymer (α-Olefin Random Copolymer); Amide-based slip agent; Styrene-based elastomer; and propylene-based elastomer. At this time, the styrene-based elastomer and propylene-based elastomer can be described in the same way as the styrene-based elastomer of the core layer 200 and the propylene-based elastomer of the corona layer 100, respectively, and detailed descriptions are omitted.

The alpha-olefin random copolymer serves to enable high temperature adhesion of the sealant layer 300. For example, the alpha-olefin random copolymer may be Propylene-Ethylene Random Copolymer, the melt index is 7.0 g/10min to 25.0 g/10min, and the melting point is 130°C to 160°C. , the density is 0.90 g/cm ³ to 0.93 g/cm ³ , and the softening point is preferably 90° C. to 140° C., but is not limited thereto.

The amide-based slip agent may perform the same function as the amide-based slip agent included in the core layer 200. In addition, in the case of the amide-based slip agent included in the sealant layer 300, it may include all three types of Erucamide, Stearyl Erucamide, and Stearyl Steramide. . As the sealant layer 300 includes three different types of amide-based slip agents, it can be manufactured without being limited by maturing temperature or time.

Depending on the embodiment, when the sealant layer 300 includes a first sealant layer 310 and a second sealant layer 320, the first sealant layer 310 is equal to the total weight of the first sealant layer 310. 60 to 80% by weight of alpha-olefin random copolymer; 5 to 15% by weight of one amide-based slip agent; 5 to 15% by weight of styrene-based elastomer; and 5 to 15% by weight of a propylene-based elastomer, and the second sealant layer 320 includes 70 to 90% by weight of alpha-olefin random copolymer based on the total weight of the second sealant layer 320; 5 to 15% by weight of two types of amide-based slip agents; and 5 to 15% by weight of propylene-based elastomer. Also, preferably, the first sealant layer 310 contains 70% by weight of propylene-ethylene random copolymer; 10% by weight of erucamide, 10% by weight of SEBS; and 10% by weight of a metallocene propylene-based elastomer, and the second sealant layer 320 includes 80% by weight of a propylene-ethylene random copolymer; 5% by weight of stearyl erucamide; 5% by weight of stearyl stearamide; And it may include 10% by weight of metallocene propylene-based elastomer. Within the above range, slip properties can be stably maintained after the overall processing of the film, and moisture resistance, heat sealing strength, adhesive strength, etc. can be improved.

According to the embodiment, the multilayer polypropylene-based film 1000 includes corona layer 100: first core layer 210: second core layer 220: first sealant layer 310: second sealant layer 320. ) the thickness ratio may be 15:15:40:15:15. Within the above range, the overall sealing characteristics and physical properties of the multilayer polypropylene-based film 1000 can be optimized.

Depending on the embodiment, the multilayer polypropylene-based film 1000 may have a dynamic friction coefficient of 0.05 to 0.09. When having the above dynamic friction coefficient, a cell pouch for secondary batteries made of the multilayer polypropylene-based film (1000) may have a dynamic friction coefficient of about 0.1, which means that a typical cell pouch for secondary batteries has a dynamic friction coefficient of 0.2 to 0.4. This means that the slip properties are superior to those with

Depending on the embodiment, the total thickness of the multilayer polypropylene-based film 1000 may be 40 to 120 micrometers. For example, the multilayer polypropylene-based film 1000 may have a thickness of 40 micrometers, 80 micrometers, 100 micrometers, or 120 micrometers depending on its purpose and required strength.

According to an embodiment of the present invention, a cell pouch film for secondary batteries made of a multilayer polypropylene-based film (1000) is provided. Cell pouches for secondary batteries are a material made by adhering several layers of films into a pouch shape to surround and protect battery cells, including the anode, cathode, and separator, and are the most important core material in ensuring the safety of secondary batteries. In cell pouches for secondary batteries like this, sealing properties, evaluated by peel strength, etc., are important in order to stably protect the secondary battery. The cell pouch film for secondary batteries according to the present invention may be one using a multi-layer polypropylene-based film (1000) as an inner layer, and in particular, known films such as an aluminum layer and a nylon layer are sequentially laminated on the multi-layer polypropylene-based film (1000). It can be. At this time, the five-layer structure of the multilayer polypropylene film (1000) and the improved physical properties, adhesive strength, and slip characteristics of the three amide-based slip agents ensure optimal adhesion between the films, thereby ensuring excellent sealing properties. You can.

However, the multilayer polypropylene-based film 1000 of the present invention can not only be used to manufacture cell pouch films for secondary batteries, but can be commercialized into various products such as food packaging paper or industrial packaging paper, for example.

According to an embodiment of the present invention, a method for manufacturing a multilayer polypropylene-based film (1000) is provided. The method includes the steps of: (a) introducing a composition for forming a corona layer, a composition for forming a core layer, and a composition for forming a sealant layer into a T-die multilayer extruder to produce a coextruded multilayer film; (b) performing corona treatment on the prepared coextruded multilayer film; and (c) taking up and winding the corona-treated coextruded multilayer film. At this time, in step (a), the T-die multilayer extruder can be set to known extrusion conditions, in step (b), corona treatment can be performed on the surface of the corona layer according to a known method, and in step (c). Pulling and winding can be performed according to known methods.

In addition, the method may further include the step of (d) aging the pulled and wound co-extruded multilayer film for 48 to 96 hours.

Below, preferred embodiments are presented to aid understanding of the present invention. However, the following examples are provided only to make the present invention easier to understand, and the content of the present invention is not limited by the following examples.

Example: Preparation of multilayer polypropylene-based film

A multilayer polypropylene-based film was manufactured in which a corona layer, a first core layer, a second core layer, a first sealant layer, and a second sealant layer were sequentially laminated with the contents shown in Table 1 below.

division thickness Raw material content corona layer 6 μm Propylene-ethylene block copolymer 60% polybutene-1 20% Propylene-based elastomer 20% total 100% first core layer 6 μm Propylene-ethylene block copolymer 57% polybutene-1 30% SEBS 10% erucamide 3% total 100% second core layer 16 μm Propylene-ethylene block copolymer 50% polybutene-1 30% SEBS 10% erucamide 10% total 100% First sealant layer 6 μm Propylene-ethylene random copolymer 70% erucamide 10% SEBS 10% Propylene-based elastomer 10% total 100% Second sealant layer 6 μm Propylene-ethylene random copolymer 80% stearyl erucamide 5% stearyl stearamide 5% Propylene-based elastomer 10% total 100%

Specifically, the propylene-ethylene block copolymer is the first propylene-ethylene block copolymer [Hanwha Total, melt index (@2.16kg, 230°C) (ASTM: D1238) = 5.0 g/10min, density (ASTM: D1505 ) = 0.91 g/cm ³ , heat distortion temperature (ASTM: D648) = 103 ℃]: 2nd propylene-ethylene block copolymer [Poly Mirae, melt index (@2.16kg, 230 ℃) (ASTM: D1238L) = 5.0 g/10min, density (ASTM: D1505) = 0.9 g/cm ³ , heat distortion temperature (ASTM: D648) = 110 ℃]: 3rd propylene-ethylene block copolymer [Hanwha Total, melt index (@2.16kg) , 230 ℃) (ASTM: D1238) = 3.0 g/10 min, heat distortion temperature (ASTM: D648) = 105 ℃] were used in equal amounts.

In addition, polybutene-1 [lyondellbasell, melt index (@2.16kg, 190°C = 1.3 g/10min, density = 0.870 g/cm ³ ) was used as polybutene-1.

In addition, the propylene-based elastomer is a metallocene propylene-based elastomer [ExxonMobil Chemical, ethylene content = 16% by weight, melt index (@2.16kg, 230 ℃) (ASTM: D1238) = 3.0 g/10min, density (@23 ℃, ASTM: D1505 modified) = 0.862 g/cm ³ , Vicat softening point 200g (ASTM: D1525) = 53.9 ℃] was used.

In addition, SEBS [Asahi Kasei Co., Ltd., density (ISO 1183) = 0.89 g/cm ³ , melt index (@2.16kg, 230 ℃) (ISO 1133) = 4.5 g/10min, styrene/ethylene-butylene ratio = 12/88, tensile strength (ISO 37) = 9.5 MPa] was used.

In addition, the propylene-ethylene random copolymer is propylene-ethylene random copolymer [Hanwha Total, melt index (@2.16kg, 230 ℃) (ASTM: D1238) = 7.0 g/10min, melting point (HTC method) = 142 ℃ , density (ASTM: D1505) = 0.91 g/cm ³ , softening point (ASTM: D648) = 95°C] were used.

The prepared compositions were put into a T-die multilayer extruder (Product name: 5-LAYER COEXTRUSION POLYCAST® LINE FOR THE PRODUCTION OF CPP AND CPE FILM, USEFUL WIDTH 3600 MM-TYPE CFC/350F) to produce a multilayer polypropylene-based film according to the manufacturer's protocol. was manufactured.

Experimental example: Measurement of physical properties of multilayer polypropylene film

A pouch for a secondary battery was manufactured by sequentially stacking a 40 ㎛ thick aluminum layer and a 25 ㎛ thick nylon layer using an adhesive as an inner layer of the multi-layer polypropylene film prepared in Table 1, and the peel strength and heat Sealing properties such as sealing strength, electrolysis resistance, and water resistance were evaluated according to the following method. At this time, each measurement result is shown in Table 2 below.

(1) Peeling Strength: The manufactured secondary battery pouch was measured through UTM using a specimen cut into 2cm × 4cm. Afterwards, the specimen was placed with LiPF ₆ electrolyte, sealed, heated to 85°C for 24 hours, and measured through UTM. In addition, using another specimen, it was placed with LiPF ₆ electrolyte and water, sealed, heated to 85°C for 24 hours, and then measured through UTM.

(2) Heat Sealing Strength: The manufactured secondary battery pouch was measured under the conditions of 15 mm/speed and 100 mm/min using a specimen cut into 2 cm × 4 cm.

(3) Electrolytic resistance: Cut the manufactured secondary battery pouch into 2cm Then, the film was collected every 4 hours until 24 hours had passed to visually check whether peeling between films occurred. The specimen in the final state after 24 hours is shown in Figure 2.

(4) Water resistance: The manufactured pouch for secondary batteries was immersed in water at a temperature of 60°C for 7 days, and then visually observed to see whether water penetrated into the film.

division detail Peel strength Before electrolyte addition 10.74N/15mm After adding electrolyte
(85℃, 24hr) 8.42N/15mm After adding electrolyte and water (85℃, 24hr) 8.13N/15mm Heat sealing strength 74.01N/15mm Electrolytic resistance No delamination occurs water resistance Good

As shown in Table 2, in the case of the Example, it was confirmed that the sealing properties such as peel strength, heat sealing strength, electrolytic resistance, and water resistance were all excellent. In addition, as shown in Figure 2, it was confirmed that no peeling phenomenon occurred at all even after 24 hours at 85°C in the electrolyte solution.

As the specific parts of the present invention have been described in detail above, it is clear to those skilled in the art that these specific techniques are merely preferred embodiments and do not limit the scope of the present invention. It will be obvious. Accordingly, the actual scope of the present invention will be defined by the appended claims and their equivalents.

100: corona layer 200: core layer
210: first core layer 220: second core layer
300: sealant layer 310: first sealant layer
320: Second sealant layer 1000: Multilayer polypropylene-based film

Claims (16)

A multilayer polypropylene-based film,
It sequentially includes a corona layer, a core layer, and a sealant layer whose surface is treated with a corona,
The corona layer and the core layer each include an alpha-olefin block copolymer,
The core layer includes a first core layer and a second core layer,
The sealant layer includes a first sealant layer and a second sealant layer,
The first core layer contains 47 to 67% by weight of at least one alpha-olefin block copolymer; and 1 to 5% by weight of an amide-based slip agent,
The second core layer contains 40 to 60% by weight of at least one alpha-olefin block copolymer; and 5 to 15% by weight of an amide-based slip agent,
The first sealant layer contains 60 to 80% by weight of alpha-olefin random copolymer; 5 to 15% by weight of one amide-based slip agent; and 5 to 15% by weight of styrene-based elastomer,
The second sealant layer contains 70 to 90% by weight of alpha-olefin random copolymer; and 5 to 15% by weight of two types of amide-based slip agents. According to claim 1,
The corona layer may include one or more of the alpha-olefin block copolymers; polybutene-1; And a multilayer polypropylene-based film, characterized in that it contains a propylene-based elastomer. According to claim 2,
The corona layer includes 50 to 70% by weight of the at least one alpha-olefin block copolymer; 10 to 30% by weight of polybutene-1; and 10 to 30% by weight of the propylene-based elastomer. According to claim 1,
The core layer may include one or more of the alpha-olefin block copolymers; polybutene-1; Styrene-based elastomer; and an amide-based slip agent. According to claim 4,
The styrene-based elastomer is a multilayer polypropylene-based film, characterized in that it includes SEBS (Styrene-Ethylene/Butylene-Styrene Block Copolymer). According to claim 4,
The amide-based slip agent is a multilayer polypropylene-based film, characterized in that it contains Erucamide. According to claim 4,
The first core layer includes 20 to 40% by weight of polybutene-1; And a multilayer polypropylene-based film, characterized in that it further comprises 5 to 15% by weight of the styrene-based elastomer. According to claim 4,
The second core layer includes 20 to 40% by weight of polybutene-1; And a multilayer polypropylene-based film, characterized in that it further comprises 5 to 15% by weight of the styrene-based elastomer. According to claim 1,
The sealant layer includes an amide-based slip agent; Styrene-based elastomer; And a multilayer polypropylene-based film, characterized in that it further comprises a propylene-based elastomer. According to clause 9,
The amide-based slip agent is a multilayer polypropylene-based film, characterized in that it includes three types of erucamide, stearyl erucamide, and stearyl steramide. According to clause 9,
The first sealant layer is a multilayer polypropylene-based film, characterized in that it further contains 5 to 15% by weight of the propylene-based elastomer. According to clause 9,
The second sealant layer is a multilayer polypropylene-based film, characterized in that it further contains 5 to 15% by weight of the propylene-based elastomer. According to claim 1,
A multilayer polypropylene-based film, characterized in that the thickness ratio of the corona layer: the first core layer: the second core layer: the first sealant layer: the second sealant layer is 15:15:40:15:15. . According to claim 1,
The multilayer polypropylene-based film is characterized in that it has a dynamic friction coefficient of 0.05 to 0.09. According to claim 1,
A multilayer polypropylene-based film, characterized in that the total thickness of the multilayer polypropylene-based film is 40 to 120 micrometers. A cell pouch film for secondary batteries manufactured from the multilayer polypropylene-based film according to any one of claims 1 to 15.

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