Container liner for loading liquids

Abstract

The present invention relates to a container liner for loading liquid articles, wherein the liner comprises a film containing one or more layers, and at least one of the layers is an L1 layer comprising: (a) polyethylene P1 having, relative to the total weight of the L1 layer, ≥20.0 wt%, preferably ≥20.0 and ≤80.0 wt%, of the following: · a density of >900 and <915 kg / m 3 , preferably >905 and <913 kg / m 3 , determined in accordance with ASTM D1505 (2010); · a melt mass-flow rate of ≥0.1 and ≤5.0 g / 10 min, preferably ≥0.5 and ≤2.0 g / 10 min, determined in accordance with ISO 1133-1 (2011) at 190 °C using a load of 2.16 kg; and (b) polyethylene plastomer P2 having, relative to the total weight of the L1 layer, ≥20.0 wt%, preferably ≥20.0 and ≤80.0 wt%, of the following: · a density of >880 and <905 kg / m 3 , preferably >890 and <904 kg / m 3 , determined in accordance with ASTM D1505 (2010); · a melt mass-flow rate of ≥0.1 and ≤5.0 g / 10 min, preferably ≥0.5 and ≤2.0 g / 10 min, determined in accordance with ISO 1133-1 (2011) at 190 °C using a load of 2.16 kg. Such a container liner exhibits desirable high flex resistance, and combines high dart impact tolerance, and high tensile strength.

Description

[0001] The present invention relates to a container liner for loading liquids, wherein the container liner comprises a film containing a polyethylene material.

[0002] In the field of transporting goods, there is a constant drive to improve efficiency throughout the transportation process. This pursuit of increased efficiency is particularly driven by increasingly stringent requirements for transportation costs. An increase in efficiency generally leads to a reduction in transportation costs, an increase in flexibility, and a decrease in the loss of goods.

[0003] One specific way to pursue increased efficiency is to use standardized units for transporting goods. Such transport units, known as intermodal containers or shipping containers, have standardized dimensions and designs and can be transported using a variety of transportation modes, including ships, trucks, and trains, without any adjustments to the transportation means aimed at safely and reliably mounting the container onto the transportation means. That is, the containers have dimensions such that a given truck, train, or ship designed for intermodal container transportation can accommodate the vast majority of available containers. This makes it easy and efficient to transport goods, which can be loaded into the container once and then transported using multiple transportation modes. In this way, goods can be transported from one place to another with a minimum of handling.

[0004] Typically, intermodal containers are so-called "dry" containers in the form of box containers with doors at one end and corrugated steel walls. While very suitable for loading various types of dry goods, they cannot be used to transport liquid goods themselves because they are not liquid-tight. When such containers are used to transport liquid goods, these liquid goods need to be provided in a separate container to ensure the safe storage of the goods. The separate container can then be placed inside the intermodal container.

[0005] In every case where a liner is placed inside a container to make it suitable for loading liquid goods, it is required that the liner be very durable so as to minimize the defects of the transport unit caused by the transportation conditions.

[0006] Now, this is achieved according to the present invention by a container liner for loading liquid goods, wherein the liner comprises a film containing one or more layers, at least one of which is an L1 layer comprising:

[0007] (a) Polyethylene P1 having, relative to the total weight of the L1 layer, ≥ 20.0 wt%, preferably ≥ 20.0 and ≤ 80.0 wt%:

[0008] · A density of > 900 and < 915 kg / m 3 , preferably > 905 and < 913 kg / m 3 , determined in accordance with ASTM D1505 (2010);

[0009] ·A melt mass flow rate of ≥ 0.1 and ≤ 5.0 g / 10 min, preferably ≥ 0.5 and ≤ 2.0 g / 10 min, measured at 190 °C with a load of 2.16 kg in accordance with ISO 1133-1 (2011);

[0010] and

[0011] (b) A polyethylene plastomer P2 of ≥ 20.0 wt%, preferably ≥ 20.0 and ≤ 80.0 wt% relative to the total weight of the L1 layer, having the following:

[0012] · A density of > 880 and < 905 kg / m 3 , preferably > 890 and < 904 kg / m 3 , measured in accordance with ASTM D1505 (2010);

[0013] · A melt mass flow rate of ≥ 0.1 and ≤ 5.0 g / 10 min, preferably ≥ 0.5 and ≤ 2.0 g / 10 min, measured at 190 °C with a load of 2.16 kg in accordance with ISO 1133-1 (2011).

[0014] Such container liners exhibit desirable high flex resistance, and combine high dart impact resistance, as well as high tensile strength.

[0015] In the context of the present invention, the flex-crack resistance of the liner can be determined by testing a sample of the liner, such as a sample of the film contained in the liner, in accordance with ASTM F392-93 (2004), also known as the Gelbo flex test. In this test, the sample is subjected to a predetermined number of flex cycles, after which the number of small holes in the film is determined, as specified in ASTM F392-93 (2004). The fewer small holes found, the higher the flex-crack resistance.

[0016] The dart impact resistance can be determined by testing a sample of the liner, such as a sample of the film contained in the liner, in accordance with ASTM D1709 (2009), Method A, as the impact failure weight.

[0017] In a specific embodiment, the present invention relates to a container liner, wherein the polyethylene plastomer P2 has:

[0018] · A material fraction eluting at a temperature of ≤ 30.0 °C in analytical temperature rising elution fractionation (a-TREF) of ≥ 5.0 wt%, preferably ≥ 10.0 wt% relative to the total weight of the polyethylene;

[0019] · Shear storage modulus G’ measured at a shear loss modulus G” = 5000 Pa > 1000 Pa, where G’ and G” are measured at 190 °C in accordance with ISO 6721-10 (2015); and / or

[0020] · A chemical composition distribution breadth (CCDB) ≥ 15.0, preferably ≥ 20.0,

[0021] where the CCDB is determined according to Equation I:

[0022]

[0023] where

[0024] · T n-2 is the moment determined according to Equation II:

[0025]

[0026] and

[0027] · T z+2 is the moment determined according to Equation III:

[0028]

[0029] where

[0030] · w(i) is the sampling weight fraction of sample (i) taken at temperature T(i) in the a-TREF analysis relative to the total sample weight, in wt%, where T(i) > 30 °C, and for T(i) > 30 °C, the area under the a-TREF curve is normalized to a surface area = 1; and

[0031] · T(i) is the temperature at which sample (i) is taken in the a-TREF analysis, in °C.

[0032] In the context of the present invention, the melt mass flow rate is measured at 190 °C in accordance with ISO 1133-1 (2011) and expressed in g / 10 min. The melt mass flow rate can be measured with a load of 2.16 kg and is then referred to as MFR2, or with a load of 5.0 kg and is then referred to as MFR5.

[0033] In the context of the present invention, the density of the polymeric material is measured in accordance with ASTM D1505 (2010) and expressed in kg / m 3 and is represented by.

[0034] To determine the shear storage modulus G' and the shear loss modulus G", specimens prepared in accordance with ISO17855-2(2016) can be used. DMS measurements are carried out at 190 °C in accordance with ISO 6721-10(2015). The determination of G' at G" = 5000 Pa can be carried out by plotting a double logarithmic Cole-Cole plot of G' and G", where 2 data points each are selected above and below G" = 5000 Pa, so that a total of 4 data points can be used to determine the first order line, from which G' at G" = 5000 Pa is determined.

[0035] According to the present invention, analytical temperature rising elution fractionation, also known as a-TREF, can be carried out using a Polymer Char Crystaf-TREF300 equipped with a stainless steel column 15 cm long and 7.8 mm inner diameter, using a solution containing 4 mg / ml of the sample prepared in 1,2-dichlorobenzene, which solution is stabilized at a temperature of 150 °C for 1 hour with 1 g / l of Topanol CA (1,1,3-tris(3-tert-butyl-4-hydroxy-6-methylphenyl)butane) and 1 g / l of Irgafos 168 (tris(2,4-di-tert-butylphenyl) phosphite). The solution can be further stabilized at 95 °C with continuous stirring at 200 rpm for 45 minutes before analysis. For analysis, the solution is crystallized from 95 °C to 30 °C at a cooling rate of 0.1 °C / min. Elution can be carried out from 30 °C to 140 °C at a heating rate of 1 °C / min. The apparatus can be cleaned at 150 °C. The sample injection volume can be 300 μl, and the pump flow rate during elution can be 0.5 ml / min. The volume between the column and the detector can be 313 μl. In the case of the present invention, the fraction eluted at a temperature of ≤30.0 °C can be calculated by subtracting the total of the fractions eluted at >30.0 °C from 100%, so that the sum of the fractions eluted at ≤30.0 °C and the fractions eluted at >30.0 °C adds up to 100.0 wt%.

[0036] Specifically, a-TREF can be carried out using a Polymer Char Crystaf-TREF 300, using a solution containing 4 mg / ml of the polymer in 1,2-dichlorobenzene, where the solution is stabilized at a temperature of 150 °C for 1 hour with 1 g / l of 1,1,3-tris(3-tert-butyl-4-hydroxy-6-methylphenyl)butane and 1 g / l of tris(2,4-di-tert-butylphenyl) phosphite), and is further stabilized at 95 °C with continuous stirring at 200 rpm for 45 minutes, where before analysis, the solution is crystallized from 95 °C to 30 °C at a cooling rate of 0.1 °C / min and eluted from 30 °C to 140 °C at a heating rate of 1 °C / min, and where the apparatus has been cleaned at 150 °C.

[0037] In certain embodiments, the present invention also relates to a container liner, wherein the film comprises at least three layers of A / B / C or consists of three layers of A / B / C, wherein the A layer is in direct contact with the B layer, and the B layer is in direct contact with the C layer, preferably wherein the composition of the A layer is the same as the composition of the C layer. For example, at least the B layer may be the L1 layer, preferably the B layer is the L1 layer.

[0038] The film may for example comprise ≥2.5 wt%, more preferably ≥2.5 and ≤10.0 wt% of high density polyethylene, having a density of >945 and <965 kg / m 3 , determined according to ASTM D1505 (2010), preferably wherein the high density polyethylene is bimodal high density polyethylene. For example, the L1 layer may comprise a fraction of high density polyethylene, preferably having a density of >945 and <965 kg / m 3 . Preferably, the L1 layer comprises ≥2.5 and ≤15.0 wt%, or ≥5.0 and ≤12.5 wt% of high density polyethylene, preferably wherein the density of the high density polyethylene is >945 and <965 kg / m 3 , more preferably >950 and <960 kg / m 3 . The high density polyethylene may for example have an MFR2 of >0.01 and <5.0 g / 10 min, preferably >0.1 and <2.0 g / 10 min. The high density polyethylene may have an MFR5 of >1.0 and <25.0 g / 10 min, preferably >5.0 and <15.0 g / 10 min.

[0039] The high density polyethylene may for example be a homopolymer of ethylene. Alternatively, the high density polyethylene may be a copolymer of ethylene and a comonomer selected from 1-butene, 1-hexene and 4-methyl-1-pentene. For example, the high density polyethylene may be such a copolymer, which comprises: relative to the total weight of the high density polyethylene, a structural part derived from ethylene and ≥0.1 and ≤5.0 wt%, preferably ≥0.2 and ≤4.0 wt%, more preferably ≥0.5 and ≤3.0 wt% of a structural part derived from a comonomer selected from 1-butene, 1-hexene and 4-methyl-1-pentene. For example, the high density polyethylene may be such a copolymer, which comprises: relative to the total weight of the high density polyethylene, ≥90.0 wt%, preferably ≥95.0 wt%, more preferably ≥96.0 wt%, even more preferably ≥97.0 wt% of a structural part derived from ethylene, and ≥0.1 and ≤5.0 wt%, preferably ≥0.2 and ≤4.0 wt%, more preferably ≥0.5 and ≤3.0 wt% of a structural part derived from a comonomer selected from 1-butene, 1-hexene and 4-methyl-1-pentene.

[0040] The high-density polyethylene can be prepared, for example, in a gas-phase polymerization process or in a slurry polymerization process. The high-density polyethylene can be prepared, for example, using a Ziegler-type catalyst or using a Phillips-type chromium-based catalyst.

[0041] The film can, for example, have a thickness of ≥100 μm, preferably ≥100 and ≤1000 μm.

[0042] The film can, for example, have a density of <912 kg / m 3 , preferably >900 and <912 kg / m 3 as determined according to ASTM D1505 (2010).

[0043] In one embodiment, the container liner has dimensions that allow it to hold a liquid volume of 1.0 to 30.0 m 3 , preferably 1.0 to 5.0 m 3 , or 10.0 to 30.0 m 3 . Preferably, the container liner further comprises at least one closable opening for filling and / or emptying the liner, preferably the liner comprises closable openings for filling and emptying the liner.

[0044] The present invention also relates to a transport unit comprising a container liner according to the present invention, in particular wherein the container liner contains a certain volume of a liquid article. Such liquid articles can, for example, be selected from potable liquids such as beverages, syrups, oils, fats, vinegars, and detergents. Alternatively, the liquid article can be a chemical compound or preparation. Such a transport unit can, for example, be a box, preferably a cardboard box, or an intermodal container.

[0045] In one embodiment, the present invention also relates to the use of a film comprising one or more layers in a container liner for a transport unit to improve the flex resistance as determined according to ASTM F392-93 (2004), wherein at least one of said layers is an L1 layer comprising:

[0046] (a) ≥20.0 wt%, preferably ≥20.0 and ≤80.0 wt% based on the total weight of the L1 layer of a polyethylene P1 having:

[0047] · a density of >900 and <915 kg / m 3 , preferably >905 and <913 kg / m 3 as determined according to ASTM D1505 (2010);

[0048] · a melt mass flow rate of ≥0.1 and ≤5.0 g / 10 min, preferably ≥0.5 and ≤2.0 g / 10 min as determined according to ISO 1133-1 (2011) at 190 °C with a load of 2.16 kg;

[0049] and

[0050] (b) a polyethylene plastomer P2 having ≥ 20.0 wt%, preferably ≥ 20.0 and ≤ 80.0 wt% relative to the total weight of the L1 layer, with the following properties:

[0051] · > 880 and < 905 kg / m 3 , preferably > 890 and < 904 kg / m 3 density, measured according to ASTM D1505 (2010);

[0052] · a melt mass flow rate of ≥ 0.1 and ≤ 5.0 g / 10 min, preferably ≥ 0.5 and ≤ 2.0 g / 10 min, measured at 190 °C with a load of 2.16 kg according to ISO 1133-1 (2011);

[0053] wherein the container liner has dimensions allowing it to accommodate 1.0 to 30.0 m 3 volume of liquid.

[0054] The polyethylene P1 can be, for example, linear low density polyethylene. Preferably, the polyethylene P1 is a copolymer of ethylene and 1-octene. For example, the polyethylene P1 can contain ≥ 80.0 wt%, preferably ≥ 85.0 wt% of structural parts derived from ethylene relative to the total weight of the polyethylene. For example, the polyethylene P1 can contain ≥ 80.0 wt%, preferably ≥ 85.0 wt% of structural parts derived from ethylene relative to the total weight of the polyethylene, and structural parts derived from 1-octene.

[0055] For example, the polyethylene P1 can contain structural parts derived from ethylene and < 20.0 wt%, preferably < 15.0 wt% of structural parts derived from 1-octene relative to the total weight of the polyethylene. For example, the polyethylene P1 can contain structural parts derived from ethylene and > 0.0 and < 20.0 wt%, preferably > 0.0 and < 15.0 wt% of structural parts derived from 1-octene. For example, the polyethylene P1 can contain structural parts derived from ethylene and > 5.0 and < 20.0 wt%, preferably > 10.0 and < 20.0 wt%, more preferably > 10.0 and < 15.0 wt% of structural parts derived from 1-octene relative to the total weight of the polyethylene.

[0056] In one embodiment, the present invention relates to a container liner for loading liquid articles, wherein the liner comprises a film containing one or more layers, and at least one of said layers is an L1 layer comprising the following:

[0057] (a) Polyethylene P1 having the following, ≥ 20.0 wt%, preferably ≥ 20.0 and ≤ 80.0 wt% relative to the total weight of the L1 layer:

[0058] · A density > 900 and < 915 kg / m 3 , preferably > 905 and < 913 kg / m 3 , measured in accordance with ASTM D1505 (2010);

[0059] · A melt mass flow rate of ≥ 0.1 and ≤ 5.0 g / 10 min, preferably ≥ 0.5 and ≤ 2.0 g / 10 min, measured in accordance with ISO 1133-1 (2011) at 190 °C with a load of 2.16 kg;

[0060] and

[0061] (b) Polyethylene plastomer P2 having the following, ≥ 20.0 wt%, preferably ≥ 20.0 and ≤ 80.0 wt% relative to the total weight of the L1 layer:

[0062] · A density > 880 and < 905 kg / m 3 , preferably > 890 and < 904 kg / m 3 , measured in accordance with ASTM D1505 (2010);

[0063] · A melt mass flow rate of ≥ 0.1 and ≤ 5.0 g / 10 min, preferably ≥ 0.5 and ≤ 2.0 g / 10 min, measured in accordance with ISO 1133-1 (2011) at 190 °C with a load of 2.16 kg;

[0064] wherein the polyethylene P1 contains structural moieties derived from ethylene and > 5.0 and < 20.0 wt%, preferably > 10.0 and < 15.0 wt% relative to the total weight of the polyethylene P1, of structural moieties derived from 1-octene.

[0065] The polyethylene P1 may have a number average molecular weight (M n ) of ≥ 25.0, preferably ≥ 30.0 kg / mol, for example ≥ 25.0 and ≤ 45.0, preferably ≥ 30.0 and ≤ 40.0 kg / mol. For example, the polyethylene P1 may have a weight average molecular weight (M w ) of ≥ 70.0 kg / mol, preferably ≥ 85.0 kg / mol, preferably ≥ 70.0 and ≤ 125.0, more preferably ≥ 85.0 and ≤ 115 kg / mol. For example, the polyethylene P1 may have a z-average molecular weight (M z)。The polyethylene P1 may, for example, have an M of ≥2.0 and ≤4.0, preferably ≥2.5 and ≤3.5 w / M n ratio. The polyethylene P1 may, for example, have an M of ≤25.0, preferably ≤20.0, for example ≥5.0 and ≤25.0, preferably ≥5.0 and ≤20.0, more preferably ≥5.0 and ≤15.0 z / M n ratio. Here, M n is the number-average molecular weight, M w is the weight-average molecular weight, and M z is the z-average molecular weight, measured according to ASTM D6474 (2012).

[0066] The polyethylene P1 may be prepared, for example, in a gas-phase polymerization process, a slurry polymerization process, or a solution polymerization process. For example, the polyethylene P1 may be prepared, for example, in a gas-phase polymerization process, a slurry polymerization process, or a solution polymerization process in the presence of a single-site catalyst. Specifically, the polyethylene P1 may be prepared, for example, in a gas-phase polymerization process, a slurry polymerization process, or a solution polymerization process in the presence of a metallocene catalyst. For example, the polyethylene P1 may be prepared in a gas-phase polymerization process in the presence of a single-site catalyst, preferably a metallocene catalyst. For example, the polyethylene P1 may be prepared in a slurry polymerization process in the presence of a single-site catalyst, preferably a metallocene catalyst. For example, the polyethylene P1 may be prepared in a solution polymerization process in the presence of a single-site catalyst, preferably a metallocene catalyst.

[0067] The polyethylene P1 may be prepared in a polymerization process comprising a single polymerization reactor, or alternatively in a polymerization process comprising a plurality of reactors arranged in series. For example, the polyethylene P1 may be prepared in a polymerization process comprising two or three reactors arranged in series, such as two reactors arranged in series. Wherein the polymerization process involves using a plurality of reactors, and the reaction product from the previous reactor is introduced into the next arranged reactor together with additional monomers. The additional monomers may be ethylene and / or 1-octene. For example, the polyethylene P1 may be prepared in a solution polymerization process comprising two or three reactors arranged in series.

[0068] The polyethylene plastomer P2 may, for example, have a material fraction eluting at a temperature of ≤ 30.0 °C in a-TREF that is ≥ 5.0 wt%, preferably ≥ 7.5 wt%, more preferably ≥ 10.0 wt%, even more preferably ≥ 11.5 wt% relative to the total weight of the polyethylene. Preferably, the polyethylene plastomer P2 has a material fraction eluting at a temperature of ≤ 30.0 °C in a-TREF that is ≥ 5.0 wt% and ≤ 25.0 wt%, more preferably ≥ 7.5 wt% and ≤ 20.0 wt%, even more preferably ≥ 10.0 wt% and ≤ 20.0 wt%, even more preferably ≥ 11.0 wt% and ≤ 15.0 wt% relative to the total weight of the polyethylene.

[0069] The polyethylene plastomer P2 may, for example, have a storage modulus G' measured at a shear loss modulus G'' = 5000 Pa that is > 1000 Pa, preferably > 1100 Pa, more preferably > 1200 Pa, even more preferably > 1300 Pa.

[0070] The polyethylene plastomer P2 may, for example, have a CCDB of ≥ 15.0, preferably ≥ 17.5, more preferably ≥ 20.0. For example, the polyethylene plastomer P2 may have a CCDB of ≥ 15.0 and ≤ 30.0, preferably ≥ 17.5 and ≤ 25.0, more preferably ≥ 20.0 and ≤ 25.0.

[0071] Preferably, the polyethylene plastomer P2 contains structural moieties derived from ethylene that are ≥ 70.0 wt%, preferably ≥ 75.0 wt%, more preferably ≥ 80.0 wt% relative to the total weight of the polyethylene plastomer. Preferably, the polyethylene plastomer P2 contains structural moieties derived from ethylene that are ≥ 70.0 and ≤ 98.0 wt%, more preferably ≥ 75.0 and ≤ 95.0 wt%, even more preferably ≥ 80.0 and ≤ 90.0 wt% relative to the total weight of the polyethylene plastomer.

[0072] Even more preferably, the polyethylene plastomer P2 contains structural moieties derived from α-olefins having 4 to 10 carbon atoms that are ≤ 30.0 wt%, preferably ≤ 25.0 wt%, more preferably ≤ 20.0 wt% relative to the total weight of the polyethylene plastomer. The polyethylene plastomer may, for example, contain structural moieties derived from α-olefins having 4 to 10 carbon atoms that are ≥ 5.0 wt%, preferably ≥ 10.0 wt%, more preferably ≥ 15.0 wt% relative to the total weight of the polyethylene plastomer. For example, the polyethylene plastomer may contain structural moieties derived from α-olefins having 4 to 10 carbon atoms that are ≥ 5.0 and ≤ 30.0 wt%, preferably ≥ 10.0 wt% and ≤ 25.0 wt%, more preferably ≥ 15.0 and ≤ 20.0 wt% relative to the total weight of the polyethylene plastomer.

[0073] The α-olefin may contain 4 to 10 carbon atoms, such as being selected from 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene, for example being selected from 1-butene, 1-hexene, and 1-octene. For example, the α-olefin containing 4 to 10 carbon atoms is selected from 1-hexene and 1-octene. The structural moiety derived from the α-olefin containing 4 to 10 carbon atoms may be, for example, a structural moiety derived from the following: 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, or a combination thereof, preferably derived from 1-hexene or 1-octene, most preferably 1-octene.

[0074] The polyethylene plastomer P2 may, for example, contain ≤30.0 wt%, preferably ≤25.0 wt%, more preferably ≤20.0 wt% of the structural moiety derived from the α-olefin containing 4 to 10 carbon atoms, based on the total weight of the polyethylene plastomer, wherein the α-olefin containing 4 to 10 carbon atoms is selected from 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene, for example being selected from 1-butene, 1-hexene, and 1-octene. The polyethylene plastomer may, for example, contain ≥5.0 wt%, preferably ≥10.0 wt%, more preferably ≥15.0 wt% of the structural moiety derived from the α-olefin containing 4 to 10 carbon atoms, based on the total weight of the polyethylene plastomer, wherein the α-olefin containing 4 to 10 carbon atoms is selected from 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene, for example being selected from 1-butene, 1-hexene, and 1-octene. For example, the polyethylene plastomer may contain ≥5.0 and ≤30.0 wt%, preferably ≥10.0 wt% and ≤25.0 wt%, more preferably ≥15.0 and ≤20.0 wt% of the structural moiety derived from the α-olefin containing 4 to 10 carbon atoms, based on the total weight of the polyethylene plastomer, wherein the α-olefin containing 4 to 10 carbon atoms is selected from 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene, for example being selected from 1-butene, 1-hexene, and 1-octene.

[0075] The polyethylene plastomer P2 may, for example, be prepared by a solution polymerization process, preferably by polymerizing ethylene with 1-hexene and / or 1-octene. The polyethylene plastomer may, for example, be prepared using a metallocene-type catalyst, preferably by polymerizing ethylene with 1-hexene and / or 1-octene.

[0076] In certain embodiments of the present invention, the film contained in the container liner of the present invention may contain a fraction of low-density polyethylene. For example, the film may contain ≥2.5 and ≤15.0 wt% of the low-density polyethylene, based on the total weight of the film. For example, the L1 layer may contain ≥2.5 and ≤15.0 wt% of low-density polyethylene. Preferably, the density of the low-density polyethylene is >900 and <935 kg / m 3 , more preferably >910 and <930 kg / m3 , and even more preferably > 915 and < 925 kg / m 3 . Further preferably, the low-density polyethylene is a polyethylene prepared by free-radical polymerization of a reaction mixture containing ethylene (preferably consisting of ethylene as the sole reactant). For example, the low-density polyethylene can be a homopolymer. The low-density polyethylene can be prepared using a high-pressure polymerization method, such as using a high-pressure tubular polymerization method or a high-pressure autoclave polymerization method, preferably where the pressure in the polymerization reactor is > 150 MPa, such as > 150 and < 300 MPa, more preferably > 200 and < 300 MPa.

[0077] Preferably, the melt mass flow rate of the low-density polyethylene is ≥ 0.1 and ≤ 5.0 g / 10 min, preferably ≥ 0.5 and ≤ 2.0 g / 10 min, measured at 190 °C with a load of 2.16 kg in accordance with ISO 1133-1 (2011).

[0078] In certain embodiments of the present invention, the present invention relates to a container liner, wherein the L1 layer comprises ≥ 2.5 and ≤ 15.0 wt% of low-density polyethylene, preferably wherein the density of the low-density polyethylene is > 900 and < 935 kg / m 3 , preferably wherein the low-density polyethylene is a polyethylene prepared by free-radical polymerization of a reaction mixture containing ethylene, wherein preferably the melt mass flow rate of the low-density polyethylene is ≥ 0.1 and ≤ 5.0 g / 10 min, preferably ≥ 0.5 and ≤ 2.0 g / 10 min, measured at 190 °C with a load of 2.16 kg in accordance with ISO 1133-1 (2011).

[0079] In one embodiment, the film comprised in the container liner comprises at least three layers A / B / C or consists of three layers A / B / C, wherein the A layer is in direct contact with the B layer, and the B layer is in direct contact with the C layer, wherein:

[0080] · The A layer comprises ≥ 75.0 wt%, preferably ≥ 80.0 wt%, more preferably ≥ 85.0 wt% of polyethylene P1, relative to the total weight of the A layer;

[0081] · The B layer is the L1 layer; and

[0082] · The C layer comprises ≥ 75.0 wt%, preferably ≥ 80.0 wt%, more preferably ≥ 85.0 wt% of polyethylene P1, relative to the total weight of the C layer.

[0083] Preferably, the film comprised in the container liner comprises at least three layers A / B / C or consists of three layers A / B / C, wherein the A layer is in direct contact with the B layer, and the B layer is in direct contact with the C layer, wherein:

[0084] · The A layer contains ≥ 75.0 wt%, preferably ≥ 80.0 wt%, more preferably ≥ 85.0 wt% of polyethylene P1 and / or < 25.0 wt%, preferably < 20.0 wt%, more preferably < 15.0 wt% of low density polyethylene, relative to the total weight of the A layer;

[0085] · The B layer is the L1 layer; and

[0086] · The C layer contains ≥ 75.0 wt%, preferably ≥ 80.0 wt%, more preferably ≥ 85.0 wt% of polyethylene P1 and / or < 25.0 wt%, preferably < 20.0 wt%, more preferably < 15.0 wt% of low density polyethylene, relative to the total weight of the C layer.

[0087] Even more preferably, the film comprised in the container liner comprises at least three A / B / C layers or consists of three A / B / C layers, wherein the A layer is in direct contact with the B layer, and the B layer is in direct contact with the C layer, wherein:

[0088] · The A layer contains ≥ 75.0 wt%, preferably ≥ 80.0 wt%, more preferably ≥ 85.0 wt% of polyethylene P1 and / or < 25.0 wt%, preferably < 20.0 wt%, more preferably < 15.0 wt% of low density polyethylene, relative to the total weight of the A layer;

[0089] · The B layer is the L1 layer comprising: ≥ 20.0 and ≤ 80.0 wt% of polyethylene P1, ≥ 20.0 and ≤ 80.0 wt% of polyethylene plastomer P2, and ≥ 2.5 and ≤ 15.0 wt%, or ≥ 5.0 and ≤ 12.5 wt% of high density polyethylene or low density polyethylene; and

[0090] · The C layer contains ≥ 75.0 wt%, preferably ≥ 80.0 wt%, more preferably ≥ 85.0 wt% of polyethylene P1 and / or < 25.0 wt%, preferably < 20.0 wt%, more preferably < 15.0 wt% of low density polyethylene, relative to the total weight of the C layer.

[0091] Even further preferably, the film comprised in the container liner comprises at least three A / B / C layers or consists of three A / B / C layers, wherein the A layer is in direct contact with the B layer, and the B layer is in direct contact with the C layer, wherein:

[0092] · The A layer contains ≥75.0 wt% and ≤95.0 wt%, preferably ≥80.0 wt% and ≤95.0 wt%, more preferably ≥85.0 wt% and ≤95.0 wt% of polyethylene P1 and / or >5.0 and <25.0 wt%, preferably >5.0 and <20.0 wt%, more preferably >5.0 and <15.0 wt% of low density polyethylene, relative to the total weight of the A layer;

[0093] · The B layer is an L1 layer containing: ≥20.0 and ≤80.0 wt% of polyethylene P1, ≥20.0 and ≤80.0 wt% of polyethylene plastomer P2, and ≥2.5 and ≤15.0 wt%, or ≥5.0 and ≤12.5 wt% of high density polyethylene or low density polyethylene; and

[0094] · The C layer contains ≥75.0 wt% and ≤95.0 wt%, preferably ≥80.0 wt% and ≤95.0 wt%, more preferably ≥85.0 wt% and ≤95.0 wt% of polyethylene P1 and / or >5.0 and <25.0 wt%, preferably >5.0 and <20.0 wt%, more preferably >5.0 and <15.0 wt% of low density polyethylene, relative to the total weight of the C layer.

[0095] In a further embodiment of the present invention, the film contained in the container liner may comprise at least three A / B / C layers or may consist of three A / B / C layers, wherein the A layer is in direct contact with the B layer, and the B layer is in direct contact with the C layer, wherein:

[0096] · The A layer contains ≥75.0 wt% and ≤95.0 wt%, preferably ≥80.0 wt% and ≤95.0 wt%, more preferably ≥85.0 wt% and ≤95.0 wt% of polyethylene P1 and / or >5.0 and <25.0 wt%, preferably >5.0 and <20.0 wt%, more preferably >5.0 and <15.0 wt% of low density polyethylene, relative to the total weight of the A layer;

[0097] · The B layer is an L1 layer containing: ≥20.0 and ≤80.0 wt% of polyethylene P1, ≥20.0 and ≤80.0 wt% of polyethylene plastomer P2, and ≥2.5 and ≤15.0 wt%, or ≥5.0 and ≤12.5 wt% of high density polyethylene or low density polyethylene; and

[0098] · The C layer contains ≥75.0 wt% and ≤95.0 wt%, preferably ≥80.0 wt% and ≤95.0 wt%, more preferably ≥85.0 wt% and ≤95.0 wt% of polyethylene P1 and / or >5.0 and <25.0 wt%, preferably >5.0 and <20.0 wt%, more preferably >5.0 and <15.0 wt% of low density polyethylene, relative to the total weight of the C layer;

[0099] The composition of the A layer is the same as that of the C layer.

[0100] For example, the A layer may have a thickness of ≥ 10.0 and ≤ 50.0 μm, preferably ≥ 20.0 and ≤ 40.0 μm. For example, the C layer may have a thickness of ≥ 10.0 and ≤ 50.0 μm, preferably ≥ 20.0 and ≤ 40.0 μm. For example, the B layer may have a thickness of ≥ 25.0 and ≤ 75.0 μm, preferably ≥ 40.0 and ≤ 60.0 μm. For example, the A layer may have a thickness of ≥ 10.0 and ≤ 50.0 μm, preferably ≥ 20.0 and ≤ 40.0 μm, the C layer may have a thickness of ≥ 10.0 and ≤ 50.0 μm, preferably ≥ 20.0 and ≤ 40.0 μm, and the B layer may have a thickness of ≥ 25.0 and ≤ 75.0 μm, preferably ≥ 40.0 and ≤ 60.0 μm.

[0101] For example, the film included in the container liner may have a thickness of ≥ 100 and ≤ 1000 μm, preferably ≥ 100 and ≤ 300 μm, wherein the A layer accounts for ≥ 20.0 and ≤ 40.0 wt% and / or the B layer accounts for ≥ 20.0 wt% and < 60.0 wt%, and / or the C layer accounts for ≥ 20.0 and ≤ 40.0 wt%, all relative to the total weight of the film.

[0102] The present invention will now be illustrated by the following non-limiting examples.

[0103] Multiple multilayer films for container liners were prepared using the materials listed in the following table.

[0104] Materials

[0105]

[0106] Further optional properties of the above materials are listed in the following table.

[0107] LLDPE5 POP1 POP3 a-TREF<30 0.9 3.9 10.8 a-TREF 30 - 94 99.1 96.0 89.2 a-TREF > 94 0 0.1 0 CCDB 8.6 19.1 20.8 G'(Pa) at G” = 5000 Pa 1883 1372

[0108] · a-TREF < 30 represents the fraction of the polymer eluted in a-TREF in the temperature range of ≤ 30.0 °C according to the method given above, expressed in wt%, and represents the amorphous fraction of the polymer, calculated by subtracting the a-TREF 30-94 and a-TREF > 94 fractions from 100.0 wt%;

[0109] · a-TREF 30-94 represents the fraction of the polymer eluted in a-TREF in the temperature range of > 30.0 and ≤ 94.0 °C, expressed in wt%, and represents the branched fraction of the polymer;

[0110] ·The fraction of polymer eluting in the a-TREF in the temperature range >94.0 and <140 °C, expressed as wt%, and represents the linear fraction of the polymer; and

[0111] ·CCDB is the breadth of the chemical composition distribution calculated according to the method described above herein.

[0112] Using the above materials, a plurality of three-layer films were manufactured by multilayer blown film extrusion, wherein the first outer layer was provided by a first extruder, the core layer was provided by a second extruder, and the second outer layer was provided by a third extruder. Each extruder supplied the raw material to an annular die with a diameter of 60 mm and a die gap of 2.0 mm. Each extruder was a single-screw extruder with a screw diameter of 25 mm. The blow-up ratio was 2.5. The total output of the combined extruders was 8 kg / h, wherein the first extruder provided 30% of this to form the first outer layer, the second extruder provided 40% to form the core layer, and the third extruder provided 30% to form the second outer layer.

[0113] The extruders were equipped with four barrel zones and a die, where the layers were combined to form the multilayer film. The temperature in each of the individual extruder zones in each extruder was as follows:

[0114] Zone 1 (Feed Zone) 170℃ Zone 2 185℃ Zone 3 190℃ Zone 4 190℃ Die 190℃

[0115] According to the method given above, a film with a thickness of 125 μm was manufactured according to the material formulation of each layer given below and the feed composition of each corresponding extruder.

[0116]

[0117] In the above table, all percentages should be understood as weight percentages of the specific material as part of the total weight of the material of the specific layer of each film.

[0118] The films manufactured by the above process were tested for the properties given in the following table.

[0119] Example 1 2 3 4 5 Film Density 914 914 911 911 911 Dart Impact Strength 2312 2480 2252 2552 2420 Tensile Strength MD 42 48 53 56 50 Tensile Strength TD 47 47 53 54 45 Modulus MD 139 153 128 136 128 Modulus TD 170 141 131 130 124 Puncture Force 71.3 71.0 88.0 89.6 93.2 Puncture Break 2.8 2.7 4.9 4.7 5.2 Pinhole Count 4 5.5 3 2 0.5

[0120] Wherein:

[0121] ·The film density was determined in accordance with ASTM D1505 (2010) and expressed in kg / m 3 ;

[0122] ·The dart impact strength was determined in accordance with ASTM D1709 (2016), Method A as the impact failure weight, and expressed in g;

[0123] · Tensile properties, tensile strength, and modulus (1% secant modulus) were determined in the machine direction (MD) and transverse direction (TD) of the film samples according to ASTM D882 (2012).

[0124] · Puncture force is the maximum force determined according to ASTM D5748-95 (2012), expressed in N;

[0125] · Puncture break is the puncture energy to break determined according to ASTM D5748-95 (2012), expressed in J; and

[0126] · Pinhole count is the number of pinholes that appear on a 300 cm² sample after 10,800 cycles when tested according to ASTM F392-93 (2004). 2 of the sample.

[0127] From the above results, it can be seen that the film samples of the container liner according to the present invention (represented by Examples 3-5) exhibit a reduced pinhole count, an increased maximum puncture force, and an increased puncture energy to break. This shows that such a container liner is particularly suitable for loading liquid articles because the chance of liquid leakage is significantly reduced.

Claims

1. A container liner for loading liquid articles, wherein the liner comprises a film having one or more layers, and at least one of the layers is an L1 layer comprising: (a) Polyethylene P1 having the following, which is ≥20.0 wt% relative to the total weight of the L1 layer: · > 905 and < 913 kg / m 3 The density, determined in accordance with ASTM D1505 (2010); · A melt mass flow rate of ≥0.5 and ≤2.0 g / 10 min, measured at 190 °C with a load of 2.16 kg in accordance with ISO 1133-1 (2011); and (b) Polyethylene plastomer P2 having the following, which is ≥20.0 wt% relative to the total weight of the L1 layer: · >880 and <905 kg / m 3 The density is measured in accordance with ASTM D1505 (2010); · A melt mass flow rate of ≥0.5 and ≤2.0 g / 10 min, measured at 190 °C with a load of 2.16 kg in accordance with ISO 1133-1 (2011); wherein the polyethylene plastomer P2 has · A material fraction eluting at a temperature of ≤30.0 °C in analytical temperature rising elution fractionation, which is ≥5.0 wt% relative to the total weight of the polyethylene; · A shear storage modulus G' measured at a shear loss modulus G" = 5000 Pa and >1000 Pa, where G' and G" are measured at 190 °C in accordance with ISO 6721-10 (2015); and / or · A chemical composition distribution width of ≥15.0, wherein the chemical composition distribution width is determined according to Equation I: where ·T n-2 is the moment calculated according to Equation II: and ·T z+2 is the moment calculated according to Equation III: where · w(i) is the sampling weight fraction of sample (i) taken at temperature T(i) in analytical temperature rising elution fractionation analysis relative to the total sample weight, in wt%, where T(i) > 30 °C, and for T(i) > 30 °C, the area under the analytical temperature rising elution fractionation curve is normalized to a surface area = 1; and · T(i) is the temperature at which sample (i) is taken in analytical temperature rising elution fractionation analysis, in °C.

2. The container liner according to claim 1, wherein at least one of the layers is an L1 layer comprising: (a) The polyethylene P1, which is ≥20.0 and ≤80.0 wt% relative to the total weight of the L1 layer, and (b) The polyethylene plastomer P2, which is ≥20.0 and ≤80.0 wt% relative to the total weight of the L1 layer.

3. The container liner according to claim 1, wherein the polyethylene plastomer P2 has a density of >890 and <904 kg / m 3 as determined in accordance with ASTM D1505 (2010).

4. The container liner according to claim 1, wherein the polyethylene plastomer P2 has · A material fraction eluting at a temperature of ≤30.0 °C in analytical temperature rising elution fractionation, which is ≥7.5 wt% relative to the total weight of the polyethylene; · A shear storage modulus G' measured at a shear loss modulus G" = 5000 Pa and >1100 Pa, where G' and G" are measured at 190 °C in accordance with ISO 6721-10 (2015); and / or · A chemical composition distribution width of ≥17.5, wherein the chemical composition distribution width is determined according to Equation I: where ·T n-2 is the moment calculated according to Equation II: and ·T z+2 is the moment calculated according to Equation III: where · w(i) is the sampling weight fraction of sample (i) taken at temperature T(i) in analytical temperature rising elution fractionation analysis relative to the total sample weight, in wt%, where T(i) > 30 °C, and for T(i) > 30 °C, the area under the analytical temperature rising elution fractionation curve is normalized to a surface area = 1; and · T(i) is the temperature at which sample (i) is taken in analytical temperature rising elution fractionation, in °C.

5. The container liner according to claim 4, wherein the polyethylene plastomer P2 has · a material fraction eluting at a temperature of ≤ 30.0 °C in analytical temperature rising elution fractionation that is ≥ 10.0 wt% relative to the total weight of the polyethylene; and / or · a chemical composition distribution breadth of ≥ 20.

0.

6. The container liner according to any one of claims 1 - 5, wherein the film comprises at least three layers of A / B / C or consists of three layers of A / B / C, wherein layer A is in direct contact with layer B, and layer B is in direct contact with layer C.

7. The container liner according to claim 6, wherein the composition of layer A is the same as the composition of layer C.

8. The container liner according to any one of claims 1 - 5, wherein at least layer B is layer L1.

9. The container liner according to any one of claims 1 - 5, wherein layer L1 comprises ≥ 2.5 and ≤ 15.0 wt% of low density polyethylene.

10. The container liner according to claim 9, wherein the low-density polyethylene has a density of > 900 and < 935 kg / m 3 , and a melt mass-flow rate of ≥ 0.1 and ≤ 5.0 g / 10 min, determined at 190 °C with a load of 2.16 kg in accordance with ISO 1133-1 (2011).

11. The container liner according to any one of claims 1-5, wherein the film comprises ≥ 2.5 wt% of high density polyethylene having a density of > 945 and < 965 kg / m 3 , determined in accordance with ASTM D1505 (2010).

12. The container liner according to claim 11, wherein the film comprises ≥ 2.5 and ≤ 10.0 wt% of high density polyethylene.

13. The container liner according to any one of claims 1 - 5, wherein the thickness of the film is ≥ 100 μm.

14. The container liner according to any one of claims 1 - 5, wherein the thickness of the film is ≥ 100 and ≤ 1000 μm.

15. The container liner according to any one of claims 1-5, wherein the density of the film is <912 kg / m 3 , measured in accordance with ASTM D1505 (2010).

16. The container liner according to any one of claims 1-5, wherein the density of the film is > 900 and < 912 kg / m 3 , as determined according to ASTM D1505 (2010).

17. The container liner according to any one of claims 1 - 5, wherein the liner has dimensions that permit the accommodation of a liquid volume of from 1.0 to 30.0 m 3 ³.

18. The container liner according to any one of claims 1 - 5, wherein the liner further comprises at least one closable opening for filling and / or emptying the liner.

19. A transport unit comprising the container liner according to any one of claims 1 - 18.

20. The transport unit according to claim 19, wherein the container liner contains a certain volume of liquid articles.

21. The transport unit according to claim 20, wherein the liquid articles are selected from potable liquids.

22. The transport unit according to claim 21, wherein the liquid articles are selected from beverages, syrups, oils, fats, vinegars, and detergents.

23. The transport unit according to any one of claims 19 - 22, wherein the transport unit is a box.

24. The transport unit according to any one of claims 19 - 22, wherein the transport unit is a cardboard box or an intermodal container.

25. Use of a film comprising one or more layers in a container liner for a transport unit for improving the flex resistance determined according to ASTM F392 - 93(2004), wherein at least one of the said layers is layer L1 comprising: (a) polyethylene P1 having the following that is ≥ 20.0 wt% relative to the total weight of layer L1: · > 905 and < 913 kg / m 3 The density, determined in accordance with ASTM D1505 (2010); · a melt mass flow rate of ≥ 0.5 and ≤ 2.0 g / 10 min, determined at 190 °C with a load of 2.16 kg in accordance with ISO 1133 - 1(2011); and (b) polyethylene plastomer P2 having the following that is ≥ 20.0 wt% relative to the total weight of layer L1: · >880 and <905 kg / m 3 Density, determined in accordance with ASTM D1505 (2010); ·A melt mass flow rate of ≥0.5 and ≤2.0 g / 10 min, measured at 190 °C with a load of 2.16 kg in accordance with ISO 1133-1 (2011); wherein the container liner has dimensions allowing it to accommodate from 1.0 to 30.0 m 3 of liquid volume; wherein the polyethylene plastomer P2 has ·A material fraction eluting at a temperature of ≤30.0 °C in analytical temperature rising elution fractionation of ≥5.0 wt% relative to the total weight of the polyethylene; ·A shear storage modulus G’ measured at a shear loss modulus G” = 5000 Pa of >1000 Pa, G’ and G” being measured at 190 °C in accordance with ISO 6721-10 (2015); and / or ·A chemical composition distribution breadth of ≥15.0, wherein the chemical composition distribution breadth is determined according to formula I: where ·T n-2 is the moment calculated according to Equation II: and ·T z+2 is the moment calculated according to Equation III: where ·w(i) is the sampling weight fraction of sample (i) taken at temperature T(i) in the analytical temperature rising elution fractionation analysis relative to the total sample weight, in wt%, where T(i) > 30 °C, and for T(i) > 30 °C, the area under the analytical temperature rising elution fractionation curve is normalized to a surface area = 1; and ·T(i) is the temperature at which sample (i) is taken in the analytical temperature rising elution fractionation analysis, in °C.

26. The use according to claim 25, wherein at least one of the layers is an L1 layer comprising: (a) ≥20.0 and ≤80.0 wt% of the polyethylene P1 relative to the total weight of the L1 layer, and (b) ≥20.0 and ≤80.0 wt% of the polyethylene plastomer P2 relative to the total weight of the L1 layer.

27. Use according to claim 25 or 26, wherein the polyethylene plastomer P2 has a density of > 890 and < 904 kg / m 3 , determined in accordance with ASTM D1505 (2010).

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