Cast film consisting of a polypropylene composition

Abstract

The present invention relates to a cast film comprising a polypropylene composition comprising a) more than 85 to less than 98 wt.-% (based on the overall weight of the polyolefin composition) of at least one polypropylene polymer (PP) having a MFR2 (according to ISO1133, 2.16 kg load at 230 °C) in the range from 1.0 to 6.0 g / 10 min, a molecular weight distribution index Mw / Mn measured by GPC (according to ISO 16014-4:2003 and ASTM D 6474-99) in the range from 4.0 to 8.0, a xylene soluble content (XCS) determined according to ISO 16152 based on the overall weight of polypropylene polymer in the range from 2.0 to 3.5 wt.-%, b) more than 2.0 to less than 15 wt.-% (based on the overall weight of the polyolefin composition) of a hydrocarbon resin product comprising a hydrocarbon resin having a glass transition temperature TG (according to ISO 11357-2:2020) of more than 50°C, preferably in the range from 50 to 125°C; and a weight average molecular weight Mw (according to ISO 16014-4:2003 and ASTM D 6474-99) in the range from 1.0 to 10.0 kg / mol; and c) optionally further additives, wherein the sum of all ingredients always adds up to 100 wt.-%.

Description

[0001] Cast film consisting of a polypropylene composition

[0002] The present invention is directed to a cast film consisting of a polypropylene composition and the use of said cast film in pharmaceutical packaging systems.

[0003] Description

[0004] Push Through Packaging (PTP) is a packaging form in which contents such as pharmaceuticals and foods are stored in a pocket created by thermoforming a plastic sheet, and an aluminum foil coated with adhesive is heat-sealed so as to seal the opening. The contents such as medicines and foods are taken out by pressing the pocket portion with a finger from the outside and pushing the foil with the contents.

[0005] A couple of basic requirements in PTP technologies are that the PTP packaging sheet should be transparent so that the state of the contents can be confirmed, should provide a barrier against water vapor to ensure the quality of the contents, should be thermoformable for molding according to the shape of the contents, and should have a certain stiffness to retain the shape of the formed cavities during storage.

[0006] Following the current industry needs and trends, packaging in pharmaceutical industry is also heavily focused on providing easily recyclable packaging for products. In particular, pharmaceutical blister packaging has gained a special attention in the recent years in Europe, as in many of them the material on the blister side is polyvinyl chloride (PVC), polyvinylidene chloride (PVDC) or fluoropolymers, while the push-through closure is made of aluminum, which essentially prevents them from being mechanically recycled. Being on the market for many years, these structures do not really have an ideal design; for instance, the aluminum layer has issues with sealing with the PVC-based layer. An additional sealant layer must be present between those two layers in order to strengthen the sealing, which in the end causes the recycling to be even more complicated and increases cost for production. In addition, the high moisture penetration capability of PVC also makes it a less-attractive material for pharmaceutical blister packaging, since it becomes challenging to preserve the content in the packaging free from any contamination.

[0007] Alternative materials to PVC-based blisters can be polyolefins, and in particular polypropylene (PP). However, it is known that for semicrystalline polymers like PP having good thermoforming ability and low water vapor transmission rate (WVTR) at the same time is a challenge. It must be stressed that most of the packaging manufacturers have only experience with PVC- based materials, which are notoriously easy to thermoform above the glass transition temperature of PVC. Therefore, any improvement in the ability of a film to be thermoformed by either starting at lower temperature or by broadening the temperature window of thermoforming is appreciated by converters.

[0008] Polypropylene based alternatives for PVC are of interest and have been developed. However, the water vapor transmission rate (WVTR) of such PP alternatives is still too high for more demanding applications.

[0009] Another approach for modifying PP based alternatives is the addition of suitable resins.

[0010] For example, WO 2008144119 A1 covers a polymeric film comprising a core layer comprising polypropylene, at least one nucleating agent and at least one hydrocarbon resin, wherein said core layer has a first side and a second side, said nucleating agent and said hydrocarbon resin being present in amounts sufficient to lower the average moisture permeability coefficient of said film in comparison to the average moisture permeability coefficient of the film in the absence of either or both of said nucleating agent and said hydrocarbon resin.

[0011] EP 3519192 B1 refers to a multilayer polyolefin film with a barrier effect against oxygen and water vapor, comprising two cover layers, two intermediate layers and one core layer, wherein the two intermediate layers and the core layer contain a hydrocarbon resin together with a nucleating agent, wherein the hydrocarbon resin is a dicyclopentadiene (DCPD), C5 or C9 resin with a softening point in the range of 120 to 160°C, and the nucleating agent is bis(4- propylbenzylidene)propylsorbitol, bis(3,4-dimethylobenzylideno) sorbitol or N-[3,5-bis(2,2- dimethylpropionylamino)phenyl]-2,2-dimethylpropionamide.

[0012] EP 3555206 B1 describes a cast film comprising a polyolefin composition comprising (A) a propylene homo- or copolymer with an MFR2 of 0.5-80 g / 10 min as measured in accordance with ISO 1133, (B) a hydrocarbon resin product comprising a hydrocarbon resin, wherein the hydrocarbon resin has a softening point of 200 °C or, and (C) a nucleating agent, wherein the cast film is obtained from the polyolefin composition in a cast film production process, wherein the chill roll has a temperature of 40-90 °C. The two main requirements for a successful blister film are low water vapor transmission rate (WVTR) combined with a sufficient mechanical property such as a good tensile modulus and storage modulus.

[0013] It was therefore an object of the present invention to provide polypropylene compositions that can fulfill these requirements with a better performance for the application in PTP packaging systems.

[0014] This object has been solved by providing a polypropylene composition for use as a cast film with the features as described in the claims.

[0015] Accordingly, a polypropylene composition for a cast film is provided, wherein the polypropylene composition comprises a) more than 85 to less than 98 wt.-% (based on the overall weight of the polyolefin composition) of at least one polypropylene polymer (PP) having a MFR2(according to ISO1133, 2.16 kg load at 230 °C) in the range from 1.0 to 6.0 g / 10 min, a molecular weight distribution index Mw / Mn measured by GPC (according to ISO 16014-4:2003 and ASTM D 6474-99) in the range from 4.0 to 8.0, a xylene soluble content (XCS) determined according to ISO 16152 based on the overall weight of polypropylene polymer in the range from 2.0 to 3.5 wt.-%, b) more than 2.0 to less than 15 wt.-% (based on the overall weight of the polyolefin composition) of a hydrocarbon resin product comprising a hydrocarbon resin having a glass transition temperature TG(according to ISO 11357-2:2020) of more than 50°C, preferably in the range from 50 to 125°C; and a weight average molecular weight Mw (according to ISO 16014-4:2003 and ASTM D 6474-99) in the range from 1.0 to 10.0 kg / mol; and c) optionally further additives, wherein the sum of all ingredients always adds up to 100 wt.-%. As will be discussed in further detail below, the cast film obtained from said polypropylene composition shows a reduced water vapor transmission rate (WVTR), a negative delta water vapor transmission rate (AWVTR) and good mechanical properties. By adding the defined amount of hydrocarbon resin to the polypropylene polymer it is possible to reduce WVTR while also increasing stiffness at ambient temperature and broadening the thermoforming window. The effect can be combined with nucleation.

[0016] Furthermore, by combining the polypropylene polymer and the hydrocarbon resin as defined in this invention it is possible to provide a monolayer structure that can be recycled rather easy.

[0017] In an embodiment of the cast film, the polypropylene composition comprises a) 90 to 97 wt.-%, preferably 92 to 96 wt.-% (based on the overall weight of the polyolefin composition) of the at least one polypropylene polymer (PP); b) 3.0 to 10 wt.-%, preferably 4.0 to 8.0 wt.-% (based on the overall weight of the polyolefin composition) of the at least one hydrocarbon resin product; and c) optionally further additives, wherein the sum of all ingredients always adds up to 100 wt.-%.

[0018] In the following the invention is defined in more detail.

[0019] The polypropylene polymer used in the present cast film polyolefin composition may be a polypropylene homopolymer or a copolymer, in particular a propylene-ethylene random copolymer.

[0020] A random copolymer is a polymer in which the monomer residues are located randomly in the polymer molecule. Random copolymers may also be known as statistical copolymers. Random copolymers are produced by simultaneous polymerization of a mixture of two or more comonomers. In random copolymers the probability of finding a given monomer residue at any given site depends only on the relative proportion of that comonomer in the reaction mixture. Propylene-ethylene random copolymers are thermoplastic resins produced via the polymerization of propylene, with ethylene bonds introduced in the polymer chain. The copolymers provide a broad range of properties.

[0021] In the present case, the propylene-ethylene random copolymer used in the polyolefin composition for the cast film has one or more of the following properties: a MFR2(according to ISO1133, 2.16 kg load at 230 °C) in the range from 1.0 to 6.0 g / 10min, preferably from 2.0 to 5.0 g / 10 min, more preferably from 2.5 to 4.5 g / 10 min, even more preferably from 3.0 and 4.0 g / 10 min, a molecular weight distribution Mw / Mn measured by GPC (according to ISO 16014- 4:2003 and ASTM D 6474-99) in the range from 4.0 to 8.0, preferably in the range from 4.5 to 6.5, more preferably in the range from 5.0 to 6.0, a melting temperature (Tm) (measured according to ISO 1 1357 / part 3 / method C2) of at least 155°C, preferably in the range of 155 to 170 °C, more preferably in the range of 158 °C to 165°C, even more preferably in the range of 160 °C to 163°C, a xylene soluble content (XCS) determined according to ISO 16152 based on the overall weight of polypropylene-ethylene random copolymer in the range from 2.0 to 3.5 wt.- %, preferably from 2.0 to 3.0 wt.-%, more preferably from 2.0 to 2.5 wt.-%, and / or an ethylene C2 content, as determined by13C-NMR spectroscopy, in the range from 0.0 to 1.0 wt.-%; preferably in the range from 0.2 to 0.8 wt.-%, even more preferably in the range from 0.5 to 0.7 wt.-%.

[0022] The synthesis of the at least one propylene-ethylene random copolymer used in the present cast film is now described.

[0023] The at least one propylene-ethylene random copolymer is obtained in a multi-stage polymerization process comprising the steps of: a) polymerizing propylene and ethylene in the presence of a Ziegler-Natta catalyst, in a first polymerization reactor (R1) and obtaining a first polymerization product; b) transferring the first polymerization product to a second polymerization reactor (R2) and obtaining a final polymerization product; and c) optionally, compounding the final polymerization product obtained in step b) with additives.

[0024] In a preferred embodiment, prior to step a) of the process described herein, a further step is conducted: aO) modifying a Ziegler-Natta catalyst, preferably with a polymeric nucleating agent, more preferably with a vinyl polymer, and pre-polymerizing propylene in a prepolymerization reactor.

[0025] The polymerization process of the propylene-ethylene random copolymer is conducted in a sequential polymerization process. The term “sequential polymerization” indicates that the propylene-ethylene random copolymer is produced in at least two reactors connected in series. Accordingly, the present polymerization system comprises at least a first polymerization reactor (R1 ) described in step a) and a second polymerization reactor (R2) as described in step b). The term “polymerization reactor” shall indicate that the main polymerization takes place. Thus, in case the process consists of two polymerization reactors, this definition does not exclude the option that the overall system comprises for instance a pre-polymerization step in a pre-polymerization reactor. The term “consist of” is only a closing formulation in view of the main polymerization reactors.

[0026] Preferably, at least one of the two polymerization reactors (R1 ) and (R2) is a gas phase reactor (GPR). It is more preferred that the second polymerization reactor (R2) is a gas phase reactor (GPR). A gas phase reactor (GPR) according to this invention is preferably a fluidized bed reactor, a fast fluidized bed reactor or a settled bed reactor or any combination thereof. Accordingly, the first polymerization reactor (R1 ) is preferably a slurry reactor (SR) and can be any continuous or simple stirred batch tank reactor or loop reactor operating in bulk or slurry. Bulk means a polymerization in a reaction medium that comprises of at least 60 % (w / w) monomer. According to the present invention the slurry reactor (SR) is preferably a (bulk) loop reactor (LR).

[0027] Preferably, the propylene-ethylene random copolymer of the first polymerization reactor (R1 ), i.e. fraction produced in the first polymerization reactor (R1 ), more preferably in the polymer slurry of the loop reactor (LR), is directly fed into the second polymerization reactor (R2), i.e. into the (first) gas phase reactor (GPR1 ), without a flash step between the stages. This kind of direct feed is described in EP 887379 A, EP 887380 A, EP 887381 A and EP 991684 A. By "direct feed" is meant a process wherein the content of the first polymerization reactor (R1 ), i.e. of the loop reactor (LR), the polymer slurry comprising the the first propylene ethylene random copolymer fraction, is led directly to the next stage gas phase reactor.

[0028] Alternatively, the propylene ethylene random copolymer of the first polymerization reactor (R1 ), i.e. fraction produced in the first polymerization reactor (R1 ), may be also directed into a flash step or through a further concentration step before fed into the second polymerization reactor (R2), i.e. into the gas phase reactor (GPR). Accordingly, this "indirect feed" refers to a process wherein the content of the first polymerization reactor (R1 ), of the loop reactor (LR), i.e. the polymer slurry, is fed into the second polymerization reactor (R2), into the (first) gas phase reactor (GPR1 ), via a reaction medium separation unit and the reaction medium as a gas from the separation unit.

[0029] More specifically, the second polymerization reactor (R2) can be any mechanically mixed or fluidized bed reactor. Preferably the gas phase reactors (GPRs) comprise a mechanically agitated fluid bed reactor with gas velocities of at least 0.2 m / sec. Thus, it is appreciated that the gas phase reactor is a fluidized bed type reactor preferably with a mechanical stirrer.

[0030] Thus, in a preferred embodiment the first polymerization reactor (R1 ) is a slurry reactor (SR), like loop reactor (LR), whereas the second polymerization reactor (R2) is gas phase reactor (GPR). Accordingly for the instant process two polymerization reactors (R1 ) and (R2), namely a slurry reactor (SR), like loop reactor (LR) and a (first) gas phase reactor (GPR1 ), connected in series are used. If needed prior to the slurry reactor (SR) a pre-polymerization reactor is placed.

[0031] The Ziegler-Natta catalyst (ZN-C) is fed into the first polymerization reactor (R1 ) and is transferred with the polymer (slurry) obtained in the first polymerization reactor (R1 ) into the subsequent reactors. If the process covers also a pre-polymerization step it is preferred that all of the Ziegler-Natta catalyst (ZN-C) is fed in the pre-polymerization reactor. Subsequently the pre-polymerization product containing the Ziegler-Natta catalyst (ZN-C) is transferred into the first polymerization reactor (R1 ).

[0032] A preferred multistage process is a “loop-gas phase”-process, such as developed by Borealis A / S, Denmark (known as BORSTAR® technology) described e.g. in patent literature, such as in EP 0 887 379, WO 92 / 12182 WO 2004 / 000899, WO 2004 / 111095, WO 99 / 24478, WO 99 / 24479 or in WO 00 / 68315. Afurther suitable slurry-gas phase process is the Spheripol® process of Basell.

[0033] Accordingly, it is preferred that the operating temperature in the first polymerization reactor (R1 ) is in the range of 62 to 90 °C, more preferably in the range of 70 to 88 °C, still more preferably in the range of 75 to 85 °C.

[0034] Alternatively, or additionally to the previous paragraph, it is preferred that the operating temperature in the second polymerization reactor (R2) is in the range of 62 to 90 °C, more preferably in the range of 70 to 88 °C, still more preferably in the range of 75 to 85 °C. Typically, the pressure in the first polymerization reactor (R1 ), preferably in the loop reactor (LR), is in the range from 2000 to 8000 kPa, preferably 3000 to 7000 kPa, like 3500 to 6500 kPa, whereas the pressure in the second polymerization reactor (R2), i.e. in the (first) gas phase reactor (GPR1 ), is in the range from 500 to 5000 kPa, preferably 1500 to 4000 kPa.

[0035] Preferably hydrogen is added in each polymerization reactor in order to control the molecular weight, i.e. the melt flow rate MFR2.

[0036] Preferably the average residence time is rather long in the polymerization reactors (R1 ) and (R2). In general, the average residence time (T) is defined as the ratio of the reaction volume (VR) to the volumetric outflow rate from the reactor (Qo) (i.e. VR / Q0), i.e T = VR / Q0[tau = VR / Q0]. In case of a loop reactor the reaction volume (VR) equals to the reactor volume.

[0037] Accordingly the average residence time (T) in the first polymerization reactor (R1 ) is preferably at least 15 min, more preferably in the range of 15 to 80 min, still more preferably in the range of 20 to 60 min, like in the range of 24 to 50 min, and / or the average residence time (T) in the second polymerization reactor (R2) is preferably at least 70 min, more preferably in the range of 70 to 220 min, still more preferably in the range of 80 to 210 min, yet more preferably in the range of 90 to 200 min, like in the range of 90 to 190 min.

[0038] In the pre-polymerization reactor (PR) a polypropylene (Pre-PP) is produced. The prepolymerization is conducted in the presence of the Ziegler-Natta catalyst (ZN-C). According to this embodiment the Ziegler-Natta catalyst (ZN-C), the co-catalyst (Co), and the external donor (ED) are all introduced to the pre-polymerization step. However, this shall not exclude the option that at a later stage for instance further co-catalyst (Co) and / or external donor (ED) is added in the polymerization process, for instance in the first reactor (R1 ). In one embodiment the Ziegler-Natta catalyst (ZN-C), the co-catalyst (Co), and the external donor (ED) are only added in the pre-polymerization reactor (PR), if a pre-polymerization is applied.

[0039] The pre-polymerization reaction is typically conducted at a temperature of 0 to 60 °C, preferably from 15 to 50 °C, and more preferably from 20 to 45 °C.

[0040] The pressure in the pre-polymerization reactor is not critical but must be sufficiently high to maintain the reaction mixture in liquid phase. Thus, the pressure may be from 2000 to 8000 kPa, for example 2200 to 7000 kPa. In a preferred embodiment, the pre-polymerization is conducted as bulk slurry polymerization in liquid propylene, i.e. the liquid phase mainly comprises propylene, with optionally inert components dissolved therein. Furthermore, according to the present invention, an ethylene feed is employed during pre-polymerization as mentioned above.

[0041] It is possible to add other components also to the pre-polymerization stage. Thus, hydrogen may be added into the pre-polymerization stage to control the molecular weight of the polypropylene (Pre-PP) as is known in the art. Further, antistatic additive may be used to prevent the particles from adhering to each other or to the walls of the reactor.

[0042] Due to the above defined process conditions in the pre-polymerization, preferably a mixture (Ml) of the Ziegler-Natta catalyst (ZN-C) and the polypropylene (Pre-PP) produced in the pre- polymerization reactor (PR) is obtained. Preferably the Ziegler-Natta catalyst (ZN-C) is (finely) dispersed in the polypropylene (Pre-PP). In other words, the Ziegler-Natta catalyst (ZN-C) particles introduced in the pre-polymerization reactor (PR) split into smaller fragments which are evenly distributed within the growing polypropylene (Pre-PP). The sizes of the introduced Ziegler-Natta catalyst (ZN-C) particles as well as of the obtained fragments are not of essential relevance for the instant invention and within the skilled knowledge.

[0043] As mentioned above, if a pre-polymerization is used, subsequent to said pre-polymerization, the mixture of the Ziegler-Natta catalyst (ZN-C) and the polypropylene (Pre-PP) produced in the pre-polymerization reactor (PR) is transferred to the first reactor (R1 ). Typically, the total amount of the polypropylene (Pre-PP) in the final propylene ethylene copolymer is rather low and typically not more than 5.0 wt.-%, more preferably not more than 4.0 wt.-%, still more preferably in the range of 0.5 to 4.0 wt.-%, like in the range of 1 .0 to 3.0 wt.-%.

[0044] As mentioned hereinabove, the Ziegler-Natta catalyst (ZN-C) may be modified in pre- polymerization step aO). The details of such modification are provided below.

[0045] In a preferred embodiment, the catalyst is a solid Ziegler-Natta catalyst comprising: i) compounds of a transition metal of Group 4 to 6 of IIIPAC; ii) a Group 2 of IIIPAC metal compound; iii) an internal donor, that is a non-phthalic compound, preferably a non-phthalic ester; iv) a co-catalyst; and v) optionally, an external donor. The catalyst comprises compounds (TC) of a transition metal of Group 4 to 6 of IUPAC, like titanium, a Group 2 metal compound (MC), like a magnesium, and an internal donor (ID) being a non-phthalic compound, preferably a non-phthalic acid ester, still more preferably being a diester of non-phthalic dicarboxylic acids as described in more detail below. Thus, the catalyst is in a preferred embodiment fully free of undesired phthalic compounds. Further, the solid catalyst is free of any external support material, like silica or MgCh, but the catalyst is selfsupported.

[0046] The Ziegler-Natta catalyst can be further defined by the way as obtained. Accordingly, the Ziegler-Natta catalyst is preferably obtained by a process comprising the steps of a) - providing a solution of at least a Group 2 metal alkoxy compound (Ax) being the reaction product of a Group 2 metal compound (MC) and a monohydric alcohol (A) comprising in addition to the hydroxyl moiety at least one ether moiety optionally in an organic liquid reaction medium; or

[0047] - a solution of at least a Group 2 metal alkoxy compound (Ax’) being the reaction product of a Group 2 metal compound (MC) and an alcohol mixture of the monohydric alcohol (A) and a monohydric alcohol (B) of formula ROH, optionally in an organic liquid reaction medium; or

[0048] - providing a solution of a mixture of the Group 2 alkoxy compound (Ax) and a Group 2 metal alkoxy compound (Bx) being the reaction product of a Group 2 metal compound (MC) and the monohydric alcohol (B), optionally in an organic liquid reaction medium; or

[0049] - providing a solution of Group 2 alkoxide of formula M(ORi)n(OR2)mX2-n-mor mixture of Group 2 alkoxides M(ORi)nX2-n’ and M(OR2)m’X2-m’, where M is Group 2 metal, X is halogen, Ri and R2 are different alkyl groups of C2 to C16 carbon atoms, and 0 < n < 2, 0 < m < 2 and n+m+(2-n-m) = 2, provided that both n and m 0, 0 < n’ < 2 and 0 < m’ < 2; and b) adding said solution from step a) to at least one compound (TC) of a transition metal of Group 4 to 6 and c) obtaining the solid catalyst component particles, and adding an internal electron donor (ID), preferably a non-phthalic internal donor (ID), at any step prior to step c).

[0050] The internal donor (ID) or precursor thereof is thus added preferably to the solution of step a) or to the transition metal compound before adding the solution of step a).

[0051] According to the procedure above the Ziegler-Natta catalyst (ZN-C) can be obtained via precipitation method or via emulsion- solidification method depending on the physical conditions, especially temperature used in steps b) and c). Emulsion is also called in this application liquid / liquid two-phase system. In both methods (precipitation or emulsionsolidification) the catalyst chemistry is the same.

[0052] In precipitation method combination of the solution of step a) with at least one transition metal compound (TC) in step b) is carried out and the whole reaction mixture is kept at least at 50 °C, more preferably in the temperature range of 55 to 110 °C, more preferably in the range of 70 to 100 °C, to secure full precipitation of the catalyst component in form of a solid particles (step c).

[0053] In emulsion - solidification method in step b) the solution of step a) is typically added to the at least one transition metal compound (TC) at a lower temperature, such as from -10 to below 50 °C, preferably from -5 to 30 °C. During agitation of the emulsion the temperature is typically kept at -10 to below 40 °C, preferably from -5 to 30 °C. Droplets of the dispersed phase of the emulsion form the active catalyst composition. Solidification (step c) of the droplets is suitably carried out by heating the emulsion to a temperature of 70 to 150 °C, preferably to 80 to 110 °C.

[0054] The catalyst prepared by emulsion - solidification method is preferably used in the present invention.

[0055] In a preferred embodiment in step a) a solution of (Ax’) or a solution of a mixture of (Ax) and (Bx) are used.

[0056] Preferably the Group 2 metal (MC) is magnesium. The magnesium alkoxy compounds as defined above can be prepared in situ in the first step of the catalyst preparation process, step a), by reacting the magnesium compound with the alcohol(s) as described above or said magnesium alkoxy compounds can be separately prepared magnesium alkoxy compounds or they can be even commercially available as ready magnesium alkoxy compounds.

[0057] Illustrative examples of alcohols (A) are glycol monoethers. Preferred alcohols (A) are C2 to C4 glycol monoethers, wherein the ether moieties comprise from 2 to 18 carbon atoms, preferably from 4 to 12 carbon atoms. Preferred examples are 2-(2-ethylhexyloxy)ethanol, 2-butyloxy ethanol, 2-hexyloxy ethanol and 1 ,3-propylene-glycol-monobutyl ether, 3-butoxy-2-propanol, with 2-(2-ethylhexyloxy)ethanol and 1 ,3-propylene-glycol-monobutyl ether, 3-butoxy-2- propanol being particularly preferred. Illustrative monohydric alcohols (B) are of formula ROH, with R being straight-chain or branched C2-C16 alkyl residue, preferably C 0 C10, more preferably C6to Cs alkyl residue. The most preferred monohydric alcohol is 2-ethyl-1 -hexanol or octanol.

[0058] Preferably a mixture of Mg alkoxy compounds (Ax) and (Bx) or mixture of alcohols (A) and (B), respectively, are used and employed in a mole ratio of Bx:Ax or B:A from 10:1 to 1 :10, more preferably 6:1 to 1 :6, most preferably 4.1 to 1 :4.

[0059] Magnesium alkoxy compound may be a reaction product of alcohol(s), as defined above, and a magnesium compound selected from dialkyl magnesium, alkyl magnesium alkoxides, magnesium dialkoxides, alkoxy magnesium halides and alkyl magnesium halides. Further, magnesium dialkoxides, magnesium diaryloxides, magnesium aryloxyhalides, magnesium aryloxides and magnesium alkyl aryloxides can be used.Alkyl groups can be a similar or different C1-C20 alkyl, preferably C2-C10 alkyl. Typical alkyl-alkoxy magnesium compounds, when used, are ethyl magnesium butoxide, butyl magnesium pentoxide, octyl magnesium butoxide and octyl magnesium octoxide. Preferably the dialkyl magnesium are used. Most preferred dialkyl magnesium are butyl octyl magnesium or butyl ethyl magnesium.

[0060] It is also possible that magnesium compound can react in addition to the alcohol (A) and alcohol (B) also with a polyhydric alcohol (C) of formula R” (OH)mto obtain said magnesium alkoxide compounds. Preferred polyhydric alcohols, if used, are alcohols, wherein R” is a straight-chain, cyclic or branched C2 to C10 hydrocarbon residue, and m is an integer of 2 to 6.

[0061] The magnesium alkoxy compounds of step a) are thus selected from the group consisting of magnesium dialkoxides, diaryloxy magnesium, alkyloxy magnesium halides, aryloxy magnesium halides, alkyl magnesium alkoxides, aryl magnesium alkoxides and alkyl magnesium aryloxides. In addition, a mixture of magnesium dihalide and a magnesium dialkoxide can be used.

[0062] The solvents to be employed for the preparation of the present catalyst may be selected among aromatic and aliphatic straight chain, branched and cyclic hydrocarbons with 5 to 20 carbon atoms, more preferably 5 to 12 carbon atoms, or mixtures thereof. Suitable solvents include benzene, toluene, cumene, xylene, pentane, hexane, heptane, octane and nonane. Hexanes and pentanes are particularly preferred. The reaction for the preparation of the magnesium alkoxy compound may be carried out at a temperature of 40 °C to 70 °C. Most suitable temperature is selected depending on the Mg compound and alcohol(s) used.

[0063] The transition metal compound of Group 4 to 6 is preferably a titanium compound, most preferably a titanium halide, like TiCk.

[0064] The internal donor (ID) used in the preparation of the catalyst used in the present invention is preferably selected from (di)esters of non-phthalic carboxylic (di)acids, 1 ,3-diethers, derivatives and mixtures thereof. Especially preferred donors are diesters of mono-unsaturated dicarboxylic acids, in particular esters belonging to a group comprising malonates, maleates, succinates, citraconates, glutarates, cyclohexene-1 ,2-dicarboxylates and benzoates, and any derivatives and / or mixtures thereof. Preferred examples are e.g. substituted maleates and citraconates, most preferably citraconates.

[0065] In emulsion method, the two-phase liquid-liquid system may be formed by simple stirring and optionally adding (further) solvent(s) and additives, such as the turbulence minimizing agent (TMA) and / or the emulsifying agents and / or emulsion stabilisers, like surfactants, which are used in a manner known in the art for facilitating the formation of and / or stabilise the emulsion. Preferably, surfactants are acrylic or methacrylic polymers. Particularly preferred are unbranched C12 to C20 (meth)acrylates such as poly(hexadecyl)-methacrylate and poly(octadecyl)-methacrylate and mixtures thereof. Turbulence minimizing agent (TMA), if used, is preferably selected from a-olefin polymers of a-olefin monomers with 6 to 20 carbon atoms, like polyoctene, polynonene, polydecene, polyundecene or polydodecene or mixtures thereof. Most preferable it is polydecene.

[0066] The solid particulate product obtained by precipitation or emulsion - solidification method may be washed at least once, preferably at least twice, most preferably at least three times with an aromatic and / or aliphatic hydrocarbon, preferably with toluene, heptane or pentane and or with TiCk. Washing solutions can also contain donors and / or compounds of Group 13, like trialkyl aluminum, halogenated alky aluminum compounds or alkoxy aluminum compounds. Aluminum compounds can also be added during the catalyst synthesis. The catalyst can further be dried, as by evaporation or flushing with nitrogen, or it can be slurried to an oily liquid without any drying step.

[0067] The finally obtained Ziegler-Natta catalyst is desirably in the form of particles having generally an average particle size range of 5 to 200 pm, preferably 10 to 100. Particles are compact with low porosity and have surface area below 20 g / m2, more preferably below 10 g / m2. Typically, the amount of Ti is 1 to 6 wt.-%, Mg 10 to 20 wt.-% and donor 10 to 40 wt.-% of the catalyst composition.

[0068] Detailed description of preparation of catalysts is disclosed in WO 2012 / 007430, EP 2610271 , EP 2610270 and EP 2610272.

[0069] The Ziegler-Natta catalyst (ZN-C) is preferably used in association with an alkyl aluminum cocatalyst and optionally external donors.

[0070] As further component in the instant polymerization process an external donor (ED) is preferably present. Suitable external donors (ED) include certain silanes, ethers, esters, amines, ketones, heterocyclic compounds and blends of these. It is especially preferred to use a silane. It is most preferred to use silanes of the general formula

[0071] RapRbqSi(ORc)(4-p-q)wherein Ra, Rband Rcdenote a hydrocarbon radical, in particular an alkyl or cycloalkyl group, and wherein p and q are numbers ranging from 0 to 3 with their sum p + q being equal to or less than 3. Ra, Rband Rccan be chosen independently from one another and can be the same or different. Specific examples of such silanes are (tert-butyl)2Si(OCH3)2, (cyclohexyl)(methyl)Si(OCH3)2, (phenyl)2Si(OCH3)2and (cyclopentyl)2Si(OCH3)2, or of general formula

[0072] Si(OCH2CH3)3(NR3R4) wherein R3and R4can be the same or different a represent a hydrocarbon group having 1 to 12 carbon atoms.

[0073] R3and R4are independently selected from the group consisting of linear aliphatic hydrocarbon group having 1 to 12 carbon atoms, branched aliphatic hydrocarbon group having 1 to 12 carbon atoms and cyclic aliphatic hydrocarbon group having 1 to 12 carbon atoms. It is in particular preferred that R3and R4are independently selected from the group consisting of methyl, ethyl, n-propyl, n-butyl, octyl, decanyl, iso-propyl, iso-butyl, iso-pentyl, tert.-butyl, tert.- amyl, neopentyl, cyclopentyl, cyclohexyl, methylcyclopentyl and cycloheptyl. More preferably both R3and R4are the same, yet more preferably both R3and R4are an ethyl group.

[0074] Especially preferred external donors (ED) are the pentyl dimethoxy silane donor (D-donor) or the cyclohexylmethyl dimethoxy silane donor (C-Donor). In addition to the Ziegler-Natta catalyst (ZN-C) and the optional external donor (ED) a cocatalyst can be used. The co-catalyst is preferably a compound of group 13 of the periodic table (IIIPAC), e.g. organo aluminum, such as an aluminum compound, like aluminum alkyl, aluminum halide or aluminum alkyl halide compound. Accordingly, in one specific embodiment the co-catalyst (Co) is a trialkylaluminum, like triethylaluminium (TEAL), dialkyl aluminum chloride or alkyl aluminum dichloride or mixtures thereof. In one specific embodiment the co- catalyst (Co) is triethylaluminium (TEAL).

[0075] Advantageously, the triethyl aluminum (TEAL) has a hydride content, expressed as AIH3, of less than 1 .0 wt.-% with respect to the triethyl aluminum (TEAL). More preferably, the hydride content is less than 0.5 wt.-%, and most preferably the hydride content is less than 0.1 wt.-%.

[0076] Preferably the ratio between the co-catalyst (Co) and the external donor (ED) [Co / ED] and / or the ratio between the co-catalyst (Co) and the transition metal (TM) [Co / TM] should be carefully chosen.

[0077] Accordingly, the mole ratio of co-catalyst (Co) to external donor (ED) [Co / ED] must be in the range of 5 to 45, preferably is in the range of 5 to 35, more preferably is in the range of 5 to 25; and optionally the mole ratio of co-catalyst (Co) to titanium compound (TC) [Co / TC] must be in the range of above 80 to 500, preferably is in the range of 100 to 350, still more preferably is in the range of 120 to 300.

[0078] As mentioned above the Ziegler-Natta catalyst (ZN-C) is preferably modified during the abovedescribed pre-polymerization step in order to introduce the polymeric nucleating agent. Details of such a modification can further be found in EP 1 183 307, EP 2 960 279 and EP 3 184 587.

[0079] Such a polymeric nucleating agent may be, as described above, a vinyl polymer, such as a vinyl polymer derived from monomers of the formula.

[0080] CH2= CH-CHR1 R2 wherein R1 and R2, together with the carbon atom they are attached to, form an optionally substituted saturated or unsaturated or aromatic ring or a fused ring system, wherein the ring or fused ring moiety contains four to 20 carbon atoms, preferably 5 to 12 membered saturated or unsaturated or aromatic ring or a fused ring system or independently represent a linear or branched C4-C30 alkane, C4- C20 cycloalkane or C4-C20 aromatic ring. Preferably R1 and R2, together with the C-atom wherein they are attached to, form a five- or six-membered saturated or unsaturated or aromatic ring or independently represent a lower alkyl group comprising from 1 to 4 carbon atoms. Preferred vinyl compounds for the preparation of a polymeric nucleating agent to be used in accordance with the present invention are in particular vinyl cycloalkanes, in particular vinyl cyclohexane (VCH), vinyl cyclopentane, and vinyl-2- methyl cyclohexane, 3-methyl-1 -butene, 3-ethyl-1 -hexene, 3-methyl-1 -pentene, 4-methyl-1 - pentene or mixtures thereof. VCH is a particularly preferred monomer.

[0081] The weight ratio of vinyl compound to polymerization catalyst in the modification step of the polymerization catalyst preferably is 0.3 or more up to 40, such as 0.4 to 20 or more preferably 0.5 to 15, like 0.5 to 2.0.

[0082] The polymerization of the vinyl compound, e.g. VCH, can be done in any inert fluid that does not dissolve the polymer formed (e. g. polyVCH). It is important to make sure that the viscosity of the final catalyst / polymerized vinyl compound / inert fluid mixture is sufficiently high to prevent the catalyst particles from settling during storage and transport.

[0083] The adjustment of the viscosity of the mixture can be done either before or after the polymerization of the vinyl compound. It is, e. g., possible to carry out the polymerization in a low viscosity oil and after the polymerization of the vinyl compound the viscosity can be adjusted by addition of a highly viscous substance. Such highly viscous substance can be a "wax", such as an oil or a mixture of an oil with a solid or highly viscous substance (oil-grease). The viscosity of such a viscous substance is usually 1 ,000 to 15,000 cP at room temperature. The advantage of using wax is that the catalyst storing and feeding into the process is improved. Since no washing, drying, sieving and transferring are needed, the catalyst activity is maintained.

[0084] The weight ratio between the oil and the solid or highly viscous polymer is preferably less than 5:1.

[0085] In addition to viscous substances, liquid hydrocarbons, such as isobutane, propane, pentane and hexane, can also be used as a medium in the modification step.

[0086] The polypropylenes produced with a catalyst modified with polymerized vinyl compounds contain essentially no free (unreacted) vinyl compounds. This means that the vinyl compounds shall be completely reacted in the catalyst modification step. To that end, the weight ratio of the (added) vinyl compound to the catalyst should be in the range of 0.05 to 10, preferably less than 3, more preferably about 0.1 to 2.0, and in particular about 0.1 to 1.5. It should be noted that no benefits are achieved by using vinyl compounds in excess. Further, the reaction time of the catalyst modification by polymerization of a vinyl compound should be sufficient to allow for complete reaction of the vinyl monomer, i. e. the polymerization is continued until the amount of unreacted vinyl compounds in the reaction mixture (including the polymerization medium and the reactants) is less than 0.5 wt.-%, in particular less than 2000 ppm by weight (shown by analysis). Thus, when the prepolymerized catalyst contains a maximum of about 0.1 wt.-% vinyl compound, the final vinyl compound content in the polypropylene will be below the limit of determination using the GC-MS method ( < 0.01 ppm by weight). Generally, when operating on an industrial scale, a polymerization time of at least 30 minutes is required, preferably the polymerization time is at least I hour and in particular at least 5 hours. Polymerization times even in the range of 6 to 50 hours can be used. The modification can be done at temperatures of 10 to 70 °C, preferably 35 to 65 °C.

[0087] A specific embodiment of the PER obtained is described in the Example section.

[0088] As mentioned above, the cast film of the present invention may be also based on a polyolefin composition comprising a polypropylene homopolymer.

[0089] Homopolymers are polymers that are made up entirely of just one monomeric compound; i.e. if the macromolecules consist of basic building blocks (monomers) of the same type, they are referred to as homopolymers.

[0090] The polypropylene homopolymer (PPH1 ) used in the present case has one or more of the following properties a MFR2(according to ISO1133, 2.16 kg load at 230 °C) in the range from 1.0 and 6.0 g / 10min, preferably from 1 .5 to 4.0 g / 10 min, more preferably from 2.0 to 3.5 g / 10 min, a molecular weight distribution Mw / Mn measured by GPC (according to ISO 16014- 4:2003 and ASTM D 6474-99) in the range from 4.0 to 8.0, preferably in the range from 4.5 to 6.5, more preferably in the range from 5.0 to 6.0, a melting temperature (Tm) (measured according to ISO 1 1357 / part 3 / method C2) of at least 160 °C, preferably in the range from 160 to 170 °C, more preferably in the range of 161 °C to 167°C, even more preferably in the range of 162 °C to 165°C, a xylene soluble content (XCS) determined according to ISO 16152 based on the overall weight of polypropylene homopolymer in the range from 2.0 to 3.5 wt.-%, preferably from 2.5 to 3.5 wt.-%, more preferably from 2.8 to 3.2 wt.-%, and / or an ethylene C2 content, as determined by13C-NMR spectroscopy, in the range from 0.0 to 0.8 wt.-%; preferably in the range from 0.0 to 0.4 wt.-%, even more preferably in the range from 0.0 to 0.2 wt.-%.

[0091] The polypropylene homopolymer PPH1 was prepared in in a multi-stage polymerization process in analogy to PER. as described for example in EP 3 255 071 A1 .

[0092] In difference to the PER synthesis process as outlined above, that the Ziegler-Natta catalyst (ZN-C) is not modified with a polymeric nucleating agent, i.e. ZN-C catalyst is not modified with a vinyl polymer derived from a vinyl monomer such as vinyl cyclohexane (VCH).

[0093] A specific embodiment of the PPH1 obtained is described in the Example section.

[0094] Hydrogenated hydrocarbon resin derives from a mixture of unsaturated monomers obtained as volatile by-products of naphtha. The resin has water resistance, wide compatibility with other resins, chemical neutrality and good electrical properties. Hydrogenated hydrocarbon resins are non-toxic and non-sensitizing to the skin.

[0095] In the present case, the hydrocarbon resin product is preferably amorphous. Amorphous hydrocarbon (HC) resins are capable of modifying the amorphous phase of polypropylenes.

[0096] The hydrocarbon resin is derived from aromatic petrochemical feedstocks. The resin is fully hydrogenated to a saturated cyclo-aliphatic structure. In an embodiment the hydrocarbon resin comprises a C5 monomer based resin and / or a dicyclopentadiene monomer based resin. The C5 monomer can include, for example, 1 -pentene, isoprene, cyclopentadiene, or 1 ,3-pentadiene monomers, or any combinations thereof. In a further embodiment, the hydrocarbon resin product comprises a C9 monomer based resin, like an indene resin, a coumarone resin, a styrene resin or a phenol resin, such as alkyl-phenol and terpene-phenol resins, and mixtures thereof.

[0097] The hydrocarbon resin product comprising a hydrocarbon resin used in the present case has one or more of the following properties: - a glass transition temperature TG(according to ISO 11357-2:2020) in the range from 50 to 125°C; preferably from 55 to 110°C, more preferably from 60 to 100°C, even more preferably from 70 to 90°C,

[0098] - a weight average molecular weight Mw (according to ISO 16014-4:2003 and ASTM D 6474-99) in the range from 1.0 to 10.0 kg / mol; preferably from 0.8 to 8.0 kg / mol, even more preferably from 1 .2 to 7.0 kg / mol, still more preferably from 1 .2 to 5.0 kg / mol, and / or

[0099] - a density in a range from 950 to 1100 kg / m3, preferably 960 to 1000 kg / m3.

[0100] According to a most preferred embodiment, the hydrocarbon resin used in the present case has one or more of the following properties: a glass transition temperature TG(according to ISO 11357-2:2020) in the range from 70 to 90 °C, preferably 75 to 85 °C, a weight average molecular weight Mw (according to ISO 16014-4:2003 and ASTM D 6474-99) in the range from 1 .2 to 3.0 kg / mol, preferably in the range from 1 .3 to 2.5 kg / mol, a weight average molecular weight Mn (according to ISO 16014-4:2003 and ASTM D 6474-99) in the range from 0.5 to 1 .5 kg / mol, preferably from 0.7 to 1 .1 kg / mol, and a density in a range from 950 to 1100 kg / m3, preferably from 960 to 1000 kg / m3.

[0101] As mentioned above the polypropylene composition used for obtaining a cast film comprises at least one polypropylene polymer (PP), preferably at least one propylene-ethylene random copolymer (PER) or at least one polypropylene homopolymer (PPH1 ), and a hydrocarbon resin product.

[0102] The polypropylene composition according to the invention has been tailored to be suited for the manufacture of cast films.

[0103] Accordingly, the polypropylene composition has one or all of the following properties: a MFR2(ISO1133, 2.16 kg load at 230 °C) in a range 1.0 to 6.0 g / 10 min, preferably from 2.5 to 15.0 g / 10 min; more preferably from 3.0 to 12.0 g / 10 min, even more preferably from 5.0 to 10.0 g / 10min, still more preferably from 5.0 to 8.0 g / 10 min, - a melting temperature Tm(according to ISO 11357 / part 3 / method C2) in the range from 155 °C to 170 °C, preferably in the range from 160 °C to 167 °C, more preferably in the range from 161 °C to 165 °C, and

[0104] - a crystallization temperature Tc(according to ISO 1 1357 / part 3 / method C2) in the range from 110 °C to 135°C, preferably in the range from 1 12°C to 130°C, more preferably in the range from 1 15°C to 128°C.

[0105] In an embodiment, the polypropylene composition comprises a) 90 to 97 wt.-%, preferably 92 to 96 wt.-% (based on the overall weight of the polyolefin composition) of the at least one propylene-ethylene random copolymer (PER) b) 3.0 to 10 wt.-%, preferably 4.0 to 8.0 wt.-% (based on the overall weight of the polyolefin composition) of the at least one hydrocarbon resin product; and c) optionally further additives, wherein the sum of all ingredients always adds up to 100 wt.-%.

[0106] The polypropylene composition comprising the at least one propylene-ethylene random copolymer (PER) and hydrocarbon resin product may have one or all of the following properties: a MFR2 (ISO1133, 2.16 kg load at 230 °C) in a range from 2.5 to 15.0 g / 10 min; preferably from 3.0 to 12.0 g / 10 min, more preferably from 4.0 to 10.0 g / 10min, still more preferably from 5.0 to 8.0 g / 10 min, even still more preferably from 6.0 to 8.0 g / 10 min,

[0107] - a melting temperature Tm(measured according to ISO 11357 / part 3 / method C2) in the range from 155 °C to 170 °C, preferably in the range from 160 °C to 167 °C, more preferably in the range from 161 °C to 165 °C,

[0108] - a crystallization temperature Tc(measured according to ISO 1 1357 / part 3 / method C2) in the range from 1 15 °C to 135°C, preferably in the range from 120°C to 130°C, more preferably in the range from 125°C to 128°C.

[0109] In a preferred embodiment, the polypropylene composition comprises c) 92 to 96 wt.-% (based on the overall weight of the polyolefin composition) of the at least one propylene-ethylene random copolymer (PER); d) 4.0 to 8.0 wt.-% (based on the overall weight of the polyolefin composition) of the at least one hydrocarbon resin product (HR-1); and c) optionally further additives, wherein the sum of all ingredients always adds up to 100 wt.-%.

[0110] The polypropylene composition comprising the at least one propylene-ethylene random copolymer (PER) and hydrocarbon resin product (HR-1 ) may have one or all of the following properties:

[0111] - a MFR2(ISO1133, 2.16 kg load at 230 °C) in a range from 5.0 to 8.0 g / 10 min, preferably from 6.0 to 8.0 g / 10 min,

[0112] - a melting temperature Tm(measured according to ISO 11357 / part 3 / method C2) in the range from 160 °C to 167 °C, preferably in the range from 161 °C to 165 °C,

[0113] - a crystallization temperature Tc(measured according to ISO 1 1357 / part 3 / method C2) in the range from 120°C to 130°C, preferably in the range from 125°C to 128°C.

[0114] In an embodiment, the polypropylene composition comprises a) 90 to 97 wt.-%, preferably 92 to 96 wt.-% (based on the overall weight of the polyolefin composition) of the at least one polypropylene homopolymer (PPH1 ), b) 3.0 to 10 wt.-%, preferably 4.0 to 8.0 wt.-% (based on the overall weight of the polyolefin composition) of the at least one hydrocarbon resin product; and c) optionally further additives, wherein the sum of all ingredients always adds up to 100 wt.-%.

[0115] The polypropylene composition comprising the at least one polypropylene homopolymer (PPH1 ) and the hydrocarbon resin product may have one or all of the following properties: a MFR2(ISO1133, 2.16 kg load at 230 °C) in a range from 2.5 to 15.0 g / 10 min; preferably from 3.0 to 12.0 g / 10 min, more preferably from 3.5 to 10.0 g / 10min, still more preferably from 4.0 to 7.0 g / 10 min, even still more preferably from 4.5 to 6.0 g / 10 min,

[0116] - a melting temperature Tm(measured according to ISO 11357 / part 3 / method C2) in the range from 155 °C to 170 °C, preferably in the range from 160 °C to 167 °C, more preferably in the range from 161 °C to 165 °C, and a crystallization temperature Tc(measured according to ISO 1 1357 / part 3 / method C2) in the range from 1 10 °C to 125°C, preferably in the range from 112°C to 120°C, more preferably in the range from 1 15°C to 118°C.

[0117] In an embodiment, the polypropylene composition comprises c) 90 to 97 wt.-%, preferably 92 to 96 wt.-% (based on the overall weight of the polyolefin composition) of the at least one polypropylene homopolymer (PPH1 ), d) 3.0 to 10 wt.-%, preferably 4.0 to 8.0 wt.-% (based on the overall weight of the polyolefin composition) of the at least one hydrocarbon resin product (HR-1); and c) optionally further additives, wherein the sum of all ingredients always adds up to 100 wt.-%.

[0118] The polypropylene composition comprising the at least one polypropylene homopolymer (PPH1 ) and the hydrocarbon resin product (HR-1 ) may have one or all of the following properties:

[0119] - a MFR2(ISO1133, 2.16 kg load at 230 °C) in a range from 4.0 to 7.0 g / 10 min, preferably from 4.5 to 6.0 g / 10 min,

[0120] - a melting temperature Tm(measured according to ISO 11357 / part 3 / method C2) in the range from 160 °C to 167 °C, preferably in the range from 161 °C to 165 °C, and

[0121] - a crystallization temperature Tc(measured according to ISO 1 1357 / part 3 / method C2) the range from 112°C to 120°C, preferably in the range from 1 15°C to 118°C.

[0122] Cast film

[0123] As mentioned, the polypropylene composition can be used for obtaining a cast film that will be used in pharmaceutical packaging systems, in particular tablet blisters.

[0124] The cast film preferably comprises a minimum weight percentage of the polypropylene composition, such as 90 wt.-%, 95% wt.-%, 98wt.-% or the like, or preferably consists of the polypropylene composition. The film according to the present invention may be produced via cast film process, where the molten polymer is passed through a flat die and the film is extruded, followed by a cooling step.

[0125] The cast film obtained may have a film thickness in a range from 100 to 1000 pm, preferably from 150 to 800 pm, more preferably from 200 to 600 pm, even more preferably from 250 to 450 pm.

[0126] Said film may be a multilayer film, like a two-layer film or a three-layer film, in which case the layer comprising the polymer composition as described herein is the main layer. According to a preferred embodiment, said film is a monolayer film.

[0127] The cast film has one or all of the following properties:

[0128] - a crystallinity Xc (as determined on 300 pm cast film by wide angle X-ray scattering measurement, WAXS, as provided in the method section) in a range from 20 to 75%, preferably in a range from 25 to 70%, more preferably in a range from more than 25 to 68%,

[0129] - a water vapor transmission rate (WVTR, at 38°C 90%RH as determined according to ISO 15106-3:2003 on a 300pm cast film) of less than 0.8 g / m2day, preferably of less than 0.6 g / m2day, more preferably of less than 0.55 g / m2day, in particular in a range from 0.2 to less than 0.8 g / m2day, more particular in a range from 0.3 to less than 0.6 g / m2day, even more particular in a range from 0.35 to less than 0.55 g / m2, still more particular in a range from 0.4 to 0.55 g / m2,

[0130] - a tensile modulus (as determined for a 300 pm cast film, according to ISO 527-3, 23°C) in a range from 800 to 2000 MPa, preferably from 900 to 1900 MPa, more preferably from 950 to 1800 MPa, a strain at break (as determined for a 300 pm cast film, according to ISO 527-3, 23°C) in a range from 3 to 800%, preferably from 5 to 750%,

[0131] - a storage modulus E’ (as determined for a 300 pm cast film, according to ISO 6721 - 4:2019, 23°C) in a range from 1400 to 2800 MPa, preferably from 1500 to 2600 MPa,

[0132] - a haze (measured according to ASTM D 1003-00) in a range of 10 to 35%, preferably in the range of 15 to 30%, more preferably in a range of 20 to 25%.

[0133] Furthermore, the present cast film may have a delta water vapor transmission rate (AWVTR, at 38°C 90%RH as determined according to ISO 15106-3:2003 on a 300pm cast film) of less than -5 %, preferably in a range from -50 to -5 %, more preferably in a range from -35 to -7 %, even more preferably in a range from - 30.0 to -9.0 %. The value of delta water vapor transmission rate (AWVTR) describes the relative change in WVTR between a cast film obtained from the base polypropylene polymer without the hydrocarbon resin and a cast film obtained from the polyolefin composition comprising the polypropylene polymer and the hydrocarbon resin. In other words, the value of delta water vapor transmission rate (AWVTR) resembles the reduction in the WVTR that is achieved when substituting small amounts of a polypropylene polymer in a conventional cast film by a hydrocarbon resin.

[0134] In still a further embodiment, the cast film (in particular a 300 pm thick cast film) made from said polypropylene composition has a thermoforming behavior as defined by Tm - Tmob in a range of 5 to 25 °C, preferably in a range of 8 to 25 °C, more preferably in a range of 8 to 23 °C. The value defined by the difference of Tm-Tmob allows to compare the ability to be thermoformed on different films. However, this value is not equal to the thermoforming window, but it is a prediction of the thermoforming behavior, the real thermoforming window can only be obtained by testing on a real thermoforming line.

[0135] In an embodiment, wherein the cast film is obtained from the polypropylene composition comprising the propylene-ethylene random copolymer (PER) and hydrocarbon resin product, the cast film has one or all of the following properties: a crystallinity Xc (as determined on 300 pm cast film by wide angle X-ray Scattering measurement, WAXS, as provided in the method section) in a range from 40 to 75%, preferably in a range from 45 to 70%, more preferably in a range from 50 to 68%,

[0136] - a water vapor transmission rate (WVTR, at 38°C 90%RH as determined according to ISO 15106-3:2003 on a 300pm cast film) of less than 0.8 g / m2day, preferably of less than 0.6 g / m2day, more preferably of less than 0.55 g / m2day, in particular in a range from 0.2 to less than 0.8 g / m2day, more particular in a range from 0.3 to less than 0.6 g / m2day, even more particular in a range from 0.35 to less than 0.55 g / m2, still more particular in a range from 0.4 to 0.55 g / m2, a delta water vapor transmission rate (AWVTR, at 38°C 90%RH as determined according to ISO 15106-3:2003 on a 300pm cast film) of less than -5%, preferably in a range from -35 to -5%, more preferably in a range from -30 to -7%, even more preferably in a range from -25.0 to -9.0%,

[0137] - a tensile modulus (as determined for a 300 pm cast film, according to ISO 527-3, 23°C) in a range from 1300 to 2000 MPa, preferably from 1400 to 1900 MPa, more preferably from 1500 to 1800 MPa, - a strain at break (as determined for a 300 pm cast film, according to ISO 527-3, 23°C) in a range from 3 to 300%, preferably from 4 to 200%, more preferably from 5 to 150%,

[0138] - a storage modulus E’ (as determined for a 300 pm cast film, according to ISO 6721 - 4:2019, 23°C) in a range from 1700 to 2600 MPa, preferably from 1800 to 2500 MPa, more preferably from 1900 to 2450 MPa, a thermoforming behavior as defined by Tm - Tmob in a range of 5 to 20 °C, preferably in a range of 6 to 15 °C, more preferably in a range of 7 to 13 °C, even more preferably in a range of 7 to 12 °C.

[0139] In a more preferred embodiment, wherein the cast film is obtained from the polypropylene composition comprising the propylene-ethylene random copolymer (PER) and hydrocarbon resin product (HR-1 ), the cast film has one or all of the following properties: a crystallinity Xc (as determined on 300 pm cast film by wide angle X-ray Scattering measurement, WAXS, as provided in the method section) in a range from 45 to 70%, more preferably in a range from 50 to 68%,

[0140] - a water vapor transmission rate (WVTR, at 38°C 90%RH as determined according to ISO 15106-3:2003 on a 300pm cast film) of less than 0.6 g / m2day, preferably of less than 0.55 g / m2day, particular in a range from 0.3 to less than 0.6 g / m2day, more particular in a range from 0.35 to less than 0.55 g / m2, still more particular in a range from 0.4 to 0.55 g / m2, a delta water vapor transmission rate (AWVTR, at 38°C 90%RH as determined according to ISO 15106-3:2003 on a 300pm cast film) in a range from -30 to -7%, preferably in a range from -25.0 to -9.0%,

[0141] - a tensile modulus (as determined for a 300 pm cast film, according to ISO 527-3, 23°C) in a range from 1400 to 1900 MPa, preferably from 1500 to 1800 MPa,

[0142] - a strain at break (as determined for a 300 pm cast film, according to ISO 527-3, 23°C) in a range from 4 to 200%, more preferably from 5 to 150%,

[0143] - a storage modulus E’ (as determined for a 300 pm cast film, according to ISO 6721 - 4:2019, 23°C) in a range 1800 to 2500 MPa, preferably from 1900 to 2450 MPa, a thermoforming behavior as defined by Tm - T mob in a range of 7 to 13 °C, even more preferably in a range of 7 to 12 °C.

[0144] In another embodiment, wherein the cast film is obtained from the polypropylene composition comprising at least one polypropylene homopolymer (PPH1 ) and the hydrocarbon resin product, the cast film has one or all of the following properties: - a crystallinity Xc (as determined on 300 pm cast film by wide angle X-ray Scattering measurement, WAXS, as provided in the method section) in a range from 20 to 75 %, preferably in a range from 22 to 70%, more preferably in a range from more than 25 to 68%,

[0145] - a water vapor transmission rate (WVTR, at 38°C 90%RH as determined according to ISO 15106-3:2003 on a 300pm cast film) of less than 0.8 g / m2day, in particular in a range from 0.2 to less than 0.8 g / m2day, more particular in a range from 0.3 to less than 0.8 g / m2day, even more particular in a range from 0.4 to less than 0.8 g / m2,

[0146] - a delta water vapor transmission rate (AWVTR, at 38°C 90%RH as determined according to ISO 15106-3:2003 on a 300pm cast film) of less than -5 %, preferably in a range from -50 to -5 %, more preferably in a range from -35 to -7 %, even more preferably in a range from - 35.0 to -9.0 %, still more preferably in a range from - 35.0 to -12.0 %,

[0147] - a tensile modulus (as determined for a 300 pm cast film, according to ISO 527-3, 23°C) in a range from 800 to 2000 MPa, preferably from 900 to 1900 MPa, more preferably from 950 to 1800 MPa,

[0148] - a strain at break (as determined for a 300 pm cast film, according to ISO 527-3, 23°C) in a range from 3 to 800%, preferably from 5 to 750%.

[0149] - a storage modulus E’ (as determined for a 300 pm cast film, according to ISO 6721 - 4:2019, 23°C) in a range from 1400 to 2800 MPa, preferably from 1500 to 2600 MPa, a thermoforming behavior as defined by Tm - Tmob in a range of 10 to 25 °C, preferably in a range of 15 to 25 °C, more preferably in a range of 18 to 23 °C, even more preferably in a range of 20 to 23 °C.

[0150] In a more preferred embodiment, wherein the cast film is obtained from the polypropylene composition comprising the polypropylene homopolymer (PPH1 ) and hydrocarbon resin product (HR-1 ), the cast film has one or all of the following properties:

[0151] - crystallinity Xc (as determined on 300 pm cast film by wide angle X-ray Scattering measurement, WAXS, as provided in the method section) in a range from 22 to 70%, more preferably in a range from more than 25 to 68%,

[0152] - a water vapor transmission rate (WVTR, at 38°C 90%RH as determined according to ISO 15106-3:2003 on a 300pm cast film) in a range from 0.3 to less than 0.8 g / m2day, particular in a range from 0.4 to less than 0.8 g / m2, - a delta water vapor transmission rate (AWVTR, at 38°C 90%RH as determined according to ISO 15106-3:2003 on a 300pm cast film) in a range from - 35.0 to - 9.0%, still more preferably in a range from - 35.0 to -12.0%,

[0153] - a tensile modulus (as determined for a 300 pm cast film, according to ISO 527-3, 23°C) in a range from 900 to 1900 MPa, preferably from 950 to 1800 MPa,

[0154] - a strain at break (as determined for a 300 pm cast film, according to ISO 527-3, 23°C) in a range from 3 to 800%, preferably from 5 to 750%.

[0155] - a storage modulus E’ (as determined for a 300 pm cast film, according to ISO 6721 - 4:2019, 23°C) in a range from 1400 to 2800 MPa, preferably from 1500 to 2600 MPa, a thermoforming behavior as defined by Tm - T mob in a range of 10 to 25 °C, in a range of 18 to 23 °C, even more preferably in a range of 20 to 23 °C.

[0156] Additives

[0157] As mentioned, the polypropylene composition comprises not more than 5.0 wt.-% , preferably not more than 4.0 wt.-%, more preferably not more than 3.0 wt.-%, even more preferably of not more than 2.0 wt.-%, still more preferably of not more than 1 .0 wt.-% of at least one additive. The polypropylene composition may comprise the at least one additive in an amount in a range from 0.01 wt.-% to 5.0 wt.-%, preferably from 0.1 wt.-% to 4.0 wt.-%, more preferably from 0.2 wt.-% to 2.0 wt.-%, even more preferably from 0.3 wt.-% to 1 .0 wt.-%.

[0158] Preferably, at least one of the at least one additive is an antioxidant. The amount of said antioxidant in the polypropylene composition may be less than 0.5 wt.-% antioxidants, more in particular less than 0.3 wt.-% antioxidants, even more in particular less than 0.2 wt.-% antioxidants.

[0159] Examples of antioxidants which are commonly used in the art, are sterically hindered phenols (such as CAS No. 6683-19-8, also sold as Irganox 1010 FF™ by BASF or Irganox B 215 FF by BASF), phosphorous based antioxidants (such as CAS No. 31570-04-4, also sold as Hostanox PAR 24 (FF)™ by Clariant, or Irgafos 168 (FF)TM by BASF), sulphur based antioxidants (such as CAS No. 693- 36-7, sold as Irganox PS-802 FL™ by BASF), nitrogenbased antioxidants (such as 4,4’- bis(1 ,1 ’-dimethylbenzyl)diphenylamine), or antioxidant blends. Preferred antioxidants may be Tris (2,4-di-t-butylphenyl) phosphite and / or Octadecyl 3-(3’,5’-di-tert. butyl-4-hydroxyphenyl)propionate. Other additives may include acid scavengers such as calcium stearate, magnesium oxide or magnesium / aluminum-hydrotalcite, slip agents such as erucamide and oleamide, antiblocking agents such as silica. It is to be noted that no Bnucleating agentis added.

[0160] Use

[0161] The present invention further pertains to a use of, an article, more preferably a film as described herein, in a blister packaging like a pharmaceutical packaging, a food packaging or a non-food packaging, like a detergent or personal care packaging. Such blister packaging comprises a thermoformed element formed from the film according to the present invention, being the recipient for the packaged goods like tablets or capsules, and an aluminum-based sheet for the push-through part. The respective blister package is closed by sealing the flat parts of said thermoformed element formed from the film according to the present invention, to the aluminum-based sheet.

[0162] The pharmaceutical packaging system, preferably tablet blister, is produced by thermoforming from a cast film as described above. The thermoforming temperature applied is in the range from 120 to 160 °C, preferably from 125 to 150 °C.

[0163] In an embodiment, the pharmaceutical packaging system has a water vapor transmission rate (WVTR, as calculated from absorption values according to USP671 at 40 °C and 75 % relative humidity) of less than 1 .0 g / m2day, preferably of less than 0.9 g / m2day, in particular in a range from 0.05 to less than 1.0 g / m2day, more particular in a range from 0.1 to less than 0.9 g / m2day, even more particular in a range from 0.15 to less than 0.8 g / m2day.

[0164] Experimental Section

[0165] The following Examples are included to demonstrate certain aspects and embodiments of the invention as described in the claims. It should be appreciated by those of skill in the art, however, that the following description is illustrative only and should not be taken in any way as a restriction of the invention.

[0166] A. MEASUREMENT METHODS

[0167] The properties of the polymers made in accordance with the present invention have been characterized according to the methods described herein, unless otherwise stated. Melt Flow Rate

[0168] The melt flow rate (MFR) was determined according to ISO 1133 and is indicated in g / 10 min. The MFR is an indication of the flowability, and hence the processability, of the polymer. The higher the melt flow rate, the lower the viscosity of the polymer. The MFR2 of polypropylene was determined at a temperature of 230 °C and a load of 2.16 kg.

[0169] Calculation of melt flow rate MFR2(230 °C) of the polymer fraction produced in the second polymerization reactor is carried out using the formula below: wherein w(A) is the weight fraction in [wt.-%] and MFR(A) is melt flow rate MFR2(230 °C) in [g / 10 min] of the first polymer fraction (A) obtained in the first polymerization reactor, w(B) is the weight fraction in [wt.-%] and MFR(B) is melt flow rate MFR2(230 °C) in [g / 10 min] of second polymer fraction (B) obtained in the second polymerization reactor,

[0170] MFR(C) is melt flow rate MFR2(230 °C) in [g / 10 min] of the polymer obtained as a result of the second polymerization step (the final polymer, which comprises both fractions (A) and (B)).

[0171] Xylene Cold Soluble (XCS) Content

[0172] The amount of the polymer soluble in xylene was determined at 25 °C according to ISO 16152; 5th edition; 2005-07-01.

[0173] Ethylene (C2) Content

[0174] Quantitative nuclear-magnetic resonance (NMR) spectroscopy was used to quantify the comonomer content and comonomer distribution of the copolymers, specifically propene-co- ethylene copolymers. Quantitative13C{1H] NMR spectra recorded in the solution-state using a Bruker Advance III 400 NMR spectrometer operating at 400.15 and 100.62 MHz for1H and13C respectively. All spectra were recorded using a13C optimised 10 mm selective excitation probe head at 125°C using nitrogen gas for all pneumatics. Approximately 200 mg of material was dissolved in 1 ,2-tetrachloroethane-c / 2(TCE-c / 2) with chromium-(lll)-acetylacetonate (Cr(acac)3) resulting in a 65 mM solution of relaxation agent in solvent (Singh, G., Kothari, A., Gupta, V., Polymer Testing 28 5 (2009), 475). This setup was chosen primarily for the high resolution and quantitative spectra needed for accurate ethylene content determination. Standard singlepulse excitation was employed without NOE, using an optimised tip angle, 1 s recycle delay and bi-level WALTZ16 decoupling scheme (Zhou, Z., Kuemmerle, R., Qiu, X., Redwine, D., Cong, R., Taha, A., Baugh, D. Winniford, B., J. Mag. Reson. 187 (2007) 225; Busico, V., Carbonniere, P., Cipullo, R., Pellecchia, R., Severn, J., Talarico, G., Macromol. Rapid Common. 2007, 28, 11289). A total of 6144 (6k) transients were acquired per spectra. Quantitative13C{1H} NMR spectra were processed, integrated and relevant quantitative properties determined from the integrals using proprietary computer programs. All chemical shifts were indirectly referenced to the central methylene group of the ethylene block (EEE) at 30.00 ppm using the chemical shift of the solvent. This approach allowed comparable referencing even when this structural unit was not present.

[0175] Characteristic signals corresponding to regio irregular propene insertion were observed (Resconi, L., Cavallo, L., Fait, A., Piemontesi, F., Chem. Rev. 2000, 100, 1253).].

[0176] Characteristic signals corresponding to the incorporation of ethylene were observed (Cheng, H. N., Macromolecules 17, 1984, 1950). The comonomer content was calculated as the mole fraction or percent of incorporated ethylene with respect to all monomer in the copolymer using the method of Wang et. al. (Wang, W-J., Zhu, S., Macromolecules 33, 2000, 1157) through integration of multiple signals spanning the whole spectral13C spectra. This analyze method was chosen for its robust nature and ability to account for the presence of regio-irregular propene insertion when needed. Integral regions were slightly adjusted to increase applicability across the whole range of encountered comonomer contents.

[0177] For systems where only isolated ethylene incorporation (PPEPP) was observed the method of Wang et. al. was modified to reduce the influence of non-zero integrals used to quantify higher order comonomer sequences. In such cases the term for the absolute ethylene content was determined based upon only

[0178] E = 0.5( Spp + SpY+ sp8 + 0.5( Sap + Say)) or

[0179] E = 0.5( IH +IG + 0.5( lc + ID )) using the same notation as Wang et. al. (Wang, W-J., Zhu, S., Macromolecules 33, 2000, 1157). The term used for absolute propylene content (P) was not modified and the mole fraction of ethylene calculated as

[0180] [E] = E / (E + P).

[0181] The comonomer content in weight percent was calculated from the mole fraction in the usual way i.e. [E wt.-%] = 100 * ( [E] * 28.06) / ( ([E] * 28.06) + ((1 -[E]) * 42.08) ).

[0182] Melting Temperature Tm and Crystallization Temperature Tc

[0183] Melting temperature Tm and crystallization temperature Tc were measured using a TA Instrument Q2000 differential scanning calorimetry (DSC) on 5 to 7 mg samples. DSC was run according to ISO 11357 / part 3 / method C2 in a heat / cool / heat cycle with a scan rate of 10 °C / min in the temperature range of -30 to +225 °C.

[0184] Crystallization temperature Tc was determined from the cooling step, while melting temperature Tm was determined from the second heating step. Molecular weight distribution

[0185] Molar mass averages (Mw and Mn) and molecular weight distribution (MWD), i.e. Mw / Mn, were determined by Gel Permeation Chromatography (GPC) according to ISO 16014-4:2003 and ASTM D 6474-99 using the following formulas: where Ai and Mi are the chromatographic peak slice area and polyolefin molecular weight (MW).

[0186] A PolymerChar GPC instrument, equipped with infrared (IR) detector was used with 3 x Olexis and 1 x Olexis Guard columns from Polymer Laboratories and 1 ,2,4-trichlorobenzene (TCB, stabilized with 250 mg / l 2,6-Di-tert-butyl-4-methyl-phenol) as solvent at 160 °C and at a constant flow rate of 1 ml / min. 200 pL of sample solution were injected per analysis. The column set was calibrated using universal calibration (according to ISO 16014-2:2003) with at least 15 narrow MWD polystyrene (PS) standards in the range of 0.5 kg / mol to 11500 kg / mol. Mark Houwink constants used for PS, PE and PP are as described per ASTM D 6474-99. All samples were prepared by dissolving 5.0 to 9.0 mg of polymer in 8 ml (at 160 °C) of stabilized TCB (same as mobile phase) for 2.5 hours at 160 °C under continuous gentle shaking in the autosampler of the GPC instrument.

[0187] Tensile Modulus

[0188] Tensile modulus in machine direction was determined in accordance with ISO 527-3 on 300 pm cast films.

[0189] Haze

[0190] Haze was determined in accordance with ASTM D1003 on 300 pm cast films.

[0191] Crystallinity from wide angle X-ray scattering measurement (WAXS)

[0192] The measurement of wide-angle X-ray scattering (WAXS) of the samples was conducted by a Bruker D8 Discover apparatus. The diffractometer was equipped with an X-ray tube with a copper target operating at 30 kV and 20mA and a GADDS 2-D detector. A point collimation (0.5 mm) was used to direct the beam onto the surface. The measurement was done in reflection geometry, and 28 angle in the range from 10° to 32.5° were measured. Data were collected for 300 s. Intensity vs. 2-theta curve was acquired with the same measurement parameters on an amorphous polypropylene sample, which was prepared by solvent extraction. An amorphous halo was obtained by smoothing the curve. The amorphous halo has been subtracted from the measured intensity vs. 2-theta curve to result in the crystalline curve.

[0193] The crystallinity index Xc can be defined by the area under the crystalline curve and the original spectrum using Challa, Hermans and Weidinger method [Challa F, Hermans PH, Weidinger A, Makromol. Chem. 56, 169 (1962)] as: area under crystalline curve Xc = - - - - - - - x 100 area under original spectrum

[0194] Water Vapor Transmission Rate (WVTR)

[0195] Water vapour transmission rate (WVTR) was measured on 300 pm cast films in accordance with ISO 15106-2.

[0196] Temperature: 38° C ± 0.5°C.

[0197] Relative Humidity: 90% ± 2%

[0198] Water vapor transmission rate (WVTR) tests on the thermoformed blister packages were performed according to LISP671 at 40 °C and 75 % relative humidity (RH). The thermoformed blister packages contained four desiccant tablets inside each cavity, which serve to absorb the moisture that diffuses through the blister film. Applied desiccant tablets are TM-80 of Unit Dose Supply, Ringoes, NJ, USA, which consist of ~ 42 wt.-% Silicon dioxide, ~ 36 wt.-% Aluminum oxide and ~ 20 wt.-% Sodium oxide, having an initial water content of ~ 2 wt.-%. Measurement of moisture absorption in the tablets is recorded by mass increase of the whole sealed blister. The WVTR per cavity can be converted to a respective area value.

[0199] The WVTR after thermoforming is recalculated from g / d / cavity (value measured via USP671 ) to g / m2 / day. It refers to the ratio of the WVTR after TF in g / d / cavity and the area of the cavity (0.0005 m2).

[0200] Dynamic mechanical thermal analysis - tensile stressed

[0201] In a dynamic mechanical thermal analysis (DMA) in tensile mode the sample is subjected to a constant load together with an applied sinusoidal tensile strain. Under low enough deformation material response is kept within the linear viscoelastic region which is independent of strain amplitude. The tensile storage modulus E' (1 ) is determined from the following equation (Dynamic mechanical analysis : a practical introduction” Kevin P. Menard © 2008 by Taylor & Francis Group, LLC, Dynamic Testing and Instrumentation, 71 -76, 2008): where

[0202] 8FAis the measured amplitude of dynamic force, in newton sAis the measured amplitude of the dynamic displacement, in metres

[0203] Lais the distance between the clamps, in metres b is the width of the specimen, in metres d is the thickness of the specimen, in metres

[0204] 8 is the measured phase angle, in degrees.

[0205] The characterization of dynamic-mechanical properties complies with ISO standards 6721 -1 , 6721 -4, 6721 -11. The measurements were performed on a “Netzsch DMA 242E Artemis” strain / stress-controlled dynamic mechanical Analyzer, equipped with a tensional-sample holder for rectangular specimen geometry. Measurements were undertaken on rectangular sample cut from film sample. The rectangular sample was prepared using a laboratory cutter for clamping the specimen. The free tensile-length is about 12 mm (±0.5mm) measured with a calliper at room temperature with an accuracy of 0.05 mm. The width and the thickness were measured using a suitable length gauge with an accuracy of 0.001 mm. The dynamic mechanical thermal analysis was performed under inert atmosphere using liquid nitrogen for cooling within the temperature range from -100°C to +160°C using a heating rate of 2 K / min, a frequency of 1 Hz, in strain-stress controlled mode with a maximum dynamic applied stress of 2.3 MPa, a static load of 0.020 MPa and a maximum strain amplitude of 0,20 %. The clamping of the specimens was performed using a torque of 7.5 cNm on screws. The annealing at the start-temperature of -100 °C was carried out with an isothermal section of 20 minutes.

[0206] Examples

[0207] Preparation of Propylene-Ethylene-Random-Copolymer (PER) la) Catalyst preparation

[0208] 3.4 liter of 2-ethylhexanol and 810 ml of propylene glycol butyl monoether ( in a molar ratio 4 / 1 ) were added to a 20 I reactor. Then 7.8 liter of a 20 % solution in toluene of BEM (butyl ethyl magnesium) provided by Crompton GmbH was slowly added to the well stirred alcohol mixture. During the addition the temperature was kept at 10 °C. After addition the temperature of the reaction mixture was raised to 60 °C and mixing was continued at this temperature for 30 minutes. Finally, after cooling to room temperature the obtained Mg-alkoxide was transferred to storage vessel.

[0209] 21 .2 g of Mg alkoxide prepared above was mixed with 4.0 ml bis(2-ethylhexyl) citraconate for 5 min. After mixing the obtained Mg complex was used immediately in the preparation of catalyst component.

[0210] 19.5 ml titanium tetrachloride was placed in a 300 ml reactor equipped with a mechanical stirrer at 25 °C. Mixing speed was adjusted to 170 rpm. 26.0 of Mg-complex prepared above was added within 30 minutes keeping the temperature at 25 °C . 3.0 ml of Viscoplex 1 -254 and 24.0 ml of heptane were added to form an emulsion. Mixing was continued for 30 minutes at 25 °C. Then the reactor temperature was raised to 90 °C within 30 minutes. The reaction mixture was stirred for further 30 minutes at 90°C. Afterwards stirring was stopped and the reaction mixture was allowed to settle for 15 minutes at 90 °C.

[0211] The solid material was washed with 100 ml of toluene, with of 30 ml of TiCI4, with 100 ml of toluene and two times with 60 ml of heptane. I ml of donor was added to the two first washings. Washings were made at 80 °C under stirring 30 min with 170 rpm. After stirring was stopped the reaction mixture was allowed to settle for 20-30 minutes and followed by siphoning.

[0212] The solid material was washed 5 times: Washings were made at 80 °C under stirring 30 min with 170 rpm. After stirring was stopped the reaction mixture was allowed to settle for 20-30 minutes and followed by siphoning.

[0213] Wash 1 : Washing was made with a mixture of 100 ml of toluene and 1 ml donor Wash 2: Washing was made with a mixture of 30 ml of TiCI4 and 1 ml of donor.

[0214] Wash 3: Washing was made with 100 ml toluene.

[0215] Wash 4: Washing was made with 60 ml of heptane.

[0216] Wash 5. Washing was made with 60 ml of heptane under 10 minutes stirring.

[0217] Afterwards stirring was stopped and the reaction mixture was allowed to settle for 10 minutes decreasing the temperature to 70 °C with subsequent siphoning, and followed by N2 sparging for 20 minutes to yield an air sensitive powder. lb) VCH modification of catalyst

[0218] 35 ml of mineral oil (Paraffinum Liquidum PL68) was added to a 125 ml stainless steel reactor followed by 0.82 g of triethyl aluminium (TEAL) and 0.33 g of dicyclopentyl dimethoxy silane (donor D) under inert conditions at room temperature. After 10 minutes 5.0 g of the catalyst prepared in 1 a (Ti content 1.4 wt.-%) was added and after additionally 20 minutes 5.0 g of vinylcyclohexane (VCH) was added.). The temperature was increased to 60 °C during 30 minutes and was kept there for 20 hours. Finally, the temperature was decreased to 20 °C and the concentration of unreacted VCH in the oil / catalyst mixture was analysed and was found to be 120 ppm weight.

[0219] Polymerization was done in a BORSTAR® PP pilot plant unit with prepolymerization reactor (Prepoly), loop reactor (Loop) and gas phase reactor (GPR1 ) according to the conditions defined in Table 1 .

[0220] Base polymer produced according to Table 1 was then mixed with different additives in an intensive mixer and IE1 was prepared in a co-rotating twin-screw extruder. Recipe and some of the properties measured on pellets are presented in Table 2, where AO1 is Irganox 1010 (supplied by BASF AG, DE), AO2 is Irgafos 168 (supplied by BASF AG, DE) and AS is Calcium stearate (Ceasit Fl supplied by Baerlocher, DE). of propylene homopolymer PPH1

[0221] The polypropylene homopolymer PPH1 was prepared in analogy to PER just without feeding ethylene comonomer and the modification of the ZN-C catalyst with a polymeric nucleating agent based on a vinyl monomer, such as VCH, according to the conditions defined in Table 1.

[0222] Further propylene homopolymers PPH2 and PPH3 were used as comparative examples. PPH2 is prepared in analogy to PER without feeding of ethylene comonomer and without using VCH during prepolymerization, according to the conditions defined in Table 1. PPH3 is prepared in analogy to PER without feeding of ethylene comonomer (in this case VCH is used during prepolymerization), according to the conditions defined in Table 1 .

[0223] Polymerization conditions, recipes and properties for PER and PPH1 are summarized in Table 1. Table 1

[0224] * Pentaerythrityl-tetrakis(3-(3’,5’-di-tert. butyl-4-hydroxyphenyl)-propionate,

[0225] CAS 6683-19-8 (Irganox 1010 from BASF AG, DE)

[0226] ** Tris (2,4-di-t-butylphenyl) phosphite, CAS 31570-04-4 (Irgafos 168 from BASF AG, DE)

[0227] *** Ca-stearate, CAS No. 1592-23-0 (Ceasit Fl from Baerlocher, DE)

[0228] ***** Synthetic hydrotalcite, SHT, CAS No. 11097-59-9 (DHT-4Afrom Kisuma Chemicals, NL) Cast film

[0229] Cast films with 300 pm thickness were produced on a SML semi-commercial cast film line with an extruder set temperature of 250 °C, with varying chillroll temperatures and throughput of 200 kg / h. Cooling step was carried out using a three chillroll unit. The line was equipped with an extruder of 075 mm diameter in a L / D ratio of 33. A high performance barrier screw, suitable for PP and PE, operates in the used extruder.

[0230] The attached die had a width of 1200 mm and the die gap varied in a range of 0.5 mm to 1 mm (standard set is 0.7 mm). The operating width of the line is 1200 mm. The chillroll unit consists of a main chillroll with a diameter of 1000 mm and two post cooling rolls each having a diameter of 400 mm. The unit is followed by a conventional winder.

[0231] The films were then characterized to study their crystallinity using wide-angle X-ray scattering (WAXS) and temperature window for thermoforming using dynamic-mechanical-thermal analysis (DMTA), results of which are also reported in Tables below.

[0232] Table 2 shows compositions of several examples (comparative-CE; inventive-IE) and chill-roll (CR) temperature for film casting.

[0233] The hydrocarbon resin HR-1 as used in the inventive examples is characterized by a Mw of 1 .5 kg / mol and a Tg of 84°C.

[0234] The hydrocarbon resin HR-2 as used in the comparative examples is characterized by a Mw of ~ 1 kg / mol and a Tg of 43°C.

[0235] Table 2 refers to cast films obtained from polyolefin compositions at different chill-roll (CR) temperatures: a) (CE1 ) cast film obtained from propylene-ethylene random copolymer (PER) at CR of 60°C; b) (CE2) cast film obtained from propylene homopolymer (PPH3) at CR of 60°C; c) (CE3) cast film obtained from propylene-ethylene random copolymer (PER) at CR of 20°C; d) (CE4) cast film obtained from polypropylene homopolymer (PPH1 ) at CR of 20°C; e) (CE5) cast film obtained from polypropylene homopolymer (PPH2) at CR of 20°C, f) (CE6) cast film obtained from propylene-ethylene random copolymer (PER) and 4 wt.-% of Hydrocarbon resin HR-2 at CR of 60°C; g) (CE7) cast film obtained from propylene-ethylene random copolymer (PER) and 8 wt.-% of Hydrocarbon resin HR-2 at CR of 60°C; h) (CE8) cast film obtained from polypropylene homopolymer (PPH1) at CR of 80°C; i) (IE1) cast film obtained from propylene-ethylene random copolymer (PER) and 4 wt.-% of Hydrocarbon resin HR-1 at CR of 60°C; j) (IE2) cast film obtained from propylene-ethylene random copolymer (PER) and 8 wt.-% of Hydrocarbon resin HR-1 at CR of 60°C; k) (IE3) cast film obtained from propylene-ethylene random copolymer (PER) and 8 wt.-% of Hydrocarbon resin HR-1 at CR of 20°C; and l) (IE4) cast film obtained from polypropylene homopolymer (PPH1 ) and 8 wt.-% of Hydrocarbon resin HR-1 at CR of 20°C, m) (IE5) cast film obtained from polypropylene homopolymer (PPH1 ) and 8 wt.-% of Hydrocarbon resin HR-1 at CR of 80°C.

[0236] Table 2: Compositions of lEs and CEs and chill-roll (CR) temperature for film casting

[0237] Properties of the comparative examples and inventive examples are summarized in Table 3.

[0238] Table 3: MFR and DSC data of IE and CE compositions As can be seen from Table 3, the addition of hydrocarbon resin increases the MFR significantly, while it hardly affects melting and crystallization behavior.

[0239] This is in line with the assumption that the hydrocarbon resins are predominantly, if not exclusively, located in the amorphous phase of the PP, which is further supported by the strong effect on the various mobility transitions - Tgand Ta,c- as shown in Figure 1 for CE1 , CE7 and IE2. As the DMA analysis was done on the films, the tensile storage modulus E’ at 23°C also reflects the cooling rate effect as defined by the chill-roll temperature (TCR).

[0240] This affects, as can be seen in the detail data of Tables 4 and 5, also the “mobilization temperature” Tmob, which is defined at a level of storage modulus E’ of 30 MPa. From experience, it corresponds to the onset of thermoformability, i.e. the lower edge of the thermoforming window. While the stiffness of the films, both as measured in dynamic mode - E’(23°C) - and in tensile mode is increased significantly, Tmob is reduced, at least suggesting the increase of the thermoforming window.

[0241] In Tables 4 and 5 and Figures 2 and 3, and Table 6 the reference base polymers are compared to the HC-resin modified compositions, one for the chill-roll temperature TCR of 60°C (Table 4 resp. Figure 2), one for the “quenching” condition at a TCR of 20°C (Table 5 resp. Figure 3) and the higher chill-roll temperature TCR of 80°C (Table 6)

[0242] In all cases, the stiffness increase and WVTR reduction are occurring in parallel for the modification with the HC resin having a higher Tg of 84°C (HCR-1 ). Modification with the other resin HCR-2 having a lower Tg of 43°C also results in a stiffness increase, but the vapor permeability is increased as well.

[0243] Table 4 - Film properties with high chill-roll (CR) temperature of 60°C (* Tmob corresponds to a storage modulus E’ of 30 MPa)

[0244] Table 5 - Film properties with low chill-roll (CR) temperature of 20°C (* Tmob corresponds to a storage modulus E’ of 30 MPa) * Mobilization temperature

[0245] Table 6 - Film properties with high chill-roll (CR) temperature of 80°C Thermoforming

[0246] The films as described before were subjected to a thermoforming and sealing process to produce pharmaceutical blisters of an outer dimension of 80 x 62 mm2with 10 oblong cavities as shown in Figures 4 and 5. A Romaco Noack N921 machine (producer: Romaco Pharmatechnik GmbH, Karlsruhe, Germany) was employed for this step, which is equipped with plug assist and rotary sealing.

[0247] Thermoforming was performed at different pre-heating temperatures to assess the thermoforming windows of the respective materials, varying in steps of 5°C. This was done for determining the minimum applicable temperature (TF minimum) in order to get fully shaped cavities, and the maximum applicable temperature (TF maximum) which still allows operation without film burning through and / or sticking to the mold. The difference between these two temperatures is called the TF window. A line speed of 30 punches per minute was used for all further analyzed blisters.

[0248] A standard aluminum film (Patz 42194 / ALU-H 20 dull-unprinted) was used as lidding film. This film has a 20 pm thick aluminum alloy core layer (54 g / m2), a polyester-based print primer on the outside and a polypropylene based sealing layer on the inside, giving a total grammage 58.3 g / m2. The lid film was not pre-heated, and the sealing pressure was adjusted to assure full closure of all cavities.

[0249] Empty and non-sealed blisters of each film were produced in parallel to optically asses the forming quality and to determine the crystallinity effects of the thermoforming process. At different positions of the cavities (see Figure 5) both the resulting film thickness and the crystallinity were determined. Thickness measurement was based on optical microscopy images taken on a cross-section of the cavity along its shorter dimension. Total crystallinity was determined by wide-angle X-ray scattering (WAXS) as for the non-thermoformed films, averaging different positions on the cavity.

[0250] The properties of blisters obtained after thermoforming the respective films of Table 6 at T(CR) 80°C are summarized in Table 7. Table 7 - Properties of blisters. As evident from Table 7, blisters obtained from films of IE5 show a better water barrier performance as lower water vapor transmission rate, in comparison with CE8, while retaining good thermoforming ability.

Claims

Claims1 . Cast film made of a polypropylene composition, wherein the polypropylene composition comprises a) more than 85 to less than 98 wt.-% (based on the overall weight of the polyolefin composition) of at least one polypropylene polymer (PP) having a MFR2(according to ISO1133, 2.16 kg load at 230 °C) in the range from 1.0 to 6.0 g / 10 min, a molecular weight distribution index Mw / Mn measured by GPC (according to ISO 16014-4:2003 and ASTM D 6474-99) in the range from 4.0 to 8.0, a xylene soluble content (XCS) determined according to ISO 16152 based on the overall weight of polypropylene polymer in the range from 2.0 to 3.5 wt.-%, b) more than 2.0 to less than 15 wt.-% (based on the overall weight of the polyolefin composition) of a hydrocarbon resin product comprising a hydrocarbon resin having a glass transition temperature TG(according to ISO 11357-2:2020) of more than 50°C, preferably in the range from 50 to 125°C; and a weight average molecular weight Mw (according to ISO 16014-4:2003 and ASTM D 6474-99) in the range from 1.0 to 10.0 kg / mol; and c) optionally further additives, wherein the sum of all ingredients always adds up to 100 wt.-%.

2. Cast film according to claim 1 , characterized in that the polypropylene composition comprises a) 90 to 97 wt.-%, preferably 92 to 96 wt.-% (based on the overall weight of the polyolefin composition) of the at least one polypropylene polymer (PP); b) 3.0 to 10 wt.-%, preferably 4.0 to 8.0 wt.-% (based on the overall weight of the polyolefin composition) of the at least one hydrocarbon resin product; and c) optionally further additives, wherein the sum of all ingredients always adds up to 100 wt.-%.

3. Cast film according to one of the preceding claims, characterized in that the at last one polypropylene polymer (PP) is at least one propylene-ethylene random copolymer (PER) having one or more of the following properties a MFR2(according to ISO1133, 2.16 kg load at 230 °C) in the range from 1.0 to 6.0 g / 10min, preferably from 2.0 to 5.0 g / 10 min, more preferably from 2.5 to 4.5 g / 10 min, even more preferably from 3.0 and 4.0 g / 10 min, a molecular weight distribution Mw / Mn measured by GPC (according to ISO 16014-4:2003 and ASTM D 6474-99) in the range from 4.0 to 8.0, preferably in the range from 4.5 to 6.5, more preferably in the range from 5.0 to 6.0, a melting temperature Tm(measured according to ISO 11357 / part 3 / method C2) of at least 155°C, preferably in the range of 155 to 170 °C, more preferably in the range of 158 °C to 165°C, even more preferably in the range of 160 °C to 163°C, a xylene soluble content (XCS) determined according to ISO 16152 based on the overall weight of polypropylene -ethylene random copolymer in the range from 2.0 to 3.5 wt.-%, preferably from 2.0 to 3.0 wt.-%, more preferably from 2.0 to 2.5 wt.-%, and / or an ethylene C2 content, as determined by13C-NMR spectroscopy, in the range from 0.0 to 1.0 wt.-%; preferably in the range from 0.2 to 0.8 wt.-%, even more preferably in the range from 0.5 to 0.7 wt.-%.

4. Cast film according to one of the claims 1 or 2, characterized in that the at last one polypropylene polymer (PP) is a polypropylene homopolymer (PPH1 ) having one or more of the following properties a MFR2(according to ISO1133, 2.16 kg load at 230 °C) in the range from 1.0 and 6.0 g / 10min, preferably from 1.5 to 4.0 g / 10 min, more preferably from 2.0 to 3.5 g / 10 min, a molecular weight distribution Mw / Mn measured by GPC (according to ISO 16014-4:2003 and ASTM D 6474-99) in the range from 4.0 to 8.0, preferably in the range from 4.5 to 6.5, more preferably in the range from 5.0 to 6.0, a melting temperature Tm(measured according to ISO 11357 / part 3 / method C2) of at least 160 °C, preferably in the range from 160 to 170 °C, more preferably in the range of 161 °C to 167°C, even more preferably in the range of 162 °C to 165°C, a xylene soluble content (XCS) determined according to ISO 16152 based on the overall weight of polypropylene homopolymer in the range from 2.0 to 3.5 wt.-%, preferably from 2.5 to 3.5 wt.-%, more preferably from 2.8 to 3.2 wt.-%, and / oran ethylene C2 content, as determined by13C-NMR spectroscopy, in the range from 0.0 to 0.8 wt.-%; preferably in the range from 0.0 to 0.4 wt.-%, even more preferably in the range from 0.0 to 0.2 wt.-%.

5. Cast film according to one of the preceding claims, characterized in that the hydrocarbon resin product comprising a hydrocarbon resin has one or more of the following properties: a glass transition temperature TG(according to ISO 11357-2:2020) in the range from 55 to 110°C, preferably from 60 to 100°C, more preferably from 70 to 90°C, and a weight average molecular weight Mw (according to ISO 16014-4:2003 and ASTM D 6474-99) in the range from 0.8 to 8.0 kg / mol, preferably from 1 .2 to 7.0 kg / mol, still more preferably from 1 .2 to 5.0 kg / mol.

6. Cast film according to one of the preceding claims, characterized in that the hydrocarbon resin product has a density in a range from 950 to 1100 kg / m3, preferably 960 to 1000 kg / m3.

7. Cast film according to one of the preceding claims, characterized in that the polypropylene composition has a MFR2(ISO1133, 2.16 kg load at 230 °C) in a range from 2.5 to 15.0 g / 10 min; preferably from 3.0 to 12.0 g / 10 min, more preferably from 5.0 to 10.0 g / 10min, still more preferably from 650 to 8.0 g / 10 min8. Cast film according to one of the preceding claims, characterized in that the polypropylene composition has a melting temperature Tm(according to ISO 1 1357 / part 3 / method C2) in the range from 155 °C to 170 °C, preferably in the range from 160 °C to 167 °C, more preferably in the range from 161 °C to 165 °C.

9. Cast film according to one of the preceding claims, characterized in that the polypropylene composition has a crystallization temperature Tc(according to ISO 11357 / part 3 / method C2) in the range from 110 °C to 135°C, preferably in the range from 112°C to 130°C, more preferably in the range from 1 15°C to 128°C.

10. Cast film according to one of the preceding claims, characterized by a film thickness in a range from 100 to 1000 pm, preferably from 150 to 800 pm, more preferably from 200 to 600 pm, even more preferably from 250 to 450 pm.1 1. Cast film according to one of the preceding claims, characterized by a crystallinity (as determined on 300 pm cast film by wide angle X-ray Scattering measurement, WAXS,as provided in the description) in a range of 20 to 75%, preferably in a range from 25 to 70%, more preferably in a range from more than 25 to 68%.

12. Cast film according to one of the preceding claims, characterized by a water vapor transmission rate (WVTR, at 38°C 90%RH as determined according to ISO 15106-3:2003 on a 300pm cast film) of less than 0.8 g / m2day, preferably of less than 0.6 g / m2day, more preferably of less than 0.55 g / m2day, in particular in a range from 0.2 to less than 0.8 g / m2day, more particular in a range from 0.3 to less than 0.6 g / m2day, even more particular in a range from 0.35 to less than 0.55 g / m2, still more particular in a range from 0.4 to 0.55 g / m2.

13. Cast film according to one of the preceding claims, characterized by a delta water vapor transmission rate (AWVTR, wherein WVTR is determined at 38°C 90%RH according to ISO 15106-3:2003 on a 300pm cast film) of less than -5 %, preferably in a range from - 50 to -5 %, more preferably in a range from -35 to -7 wt.-%, even more preferably in a range from - 30.0 to -9.0 wt.-%.

14. Cast film according to one of the preceding claims, characterized by at least one of the following properties:- a tensile modulus (as determined for a 300 pm cast film, according to ISO 527- 3, 23°C) in a range from 800 to 2000 MPa, preferably from 900 to 1900 MPa, more preferably from 950 to 1800 MPa,- a strain at break (as determined for a 300 pm cast film, according to ISO 527- 3, 23°C) in a range from 3 to 800 %, preferably from 5 to 750 %, and / or- a storage modulus E’ (as determined for a 300 pm cast film according to ISO 6721 -4:2019at 23°C) in a range from 1400 to 2600 MPa, preferably from 1500 to 2500 MPa, more preferably from 1600 to 2450 MPa.

15. Use of a cast film according to one of the preceding claims in pharmaceutical packaging systems, in particular tablet blisters.

16. Pharmaceutical packaging system, preferably tablet blister, produced by thermoforming from a cast film according to any of the claims 1 -14, preferably using a thermoforming temperature in the range of 120 to 160 °C.

17. Pharmaceutical packaging system according to claim 16, characterized by a water vapor transmission rate (WVTR, as calculated from absorption values according to USP671 at 40 °C and 75 % relative humidity) of less than 1.0 g / m2day, preferably of less than 0.9g / m2day, in particular in a range from 0.05 to less than 1 .0 g / m2day, more particular in a range from 0.1 to less than 0.9 g / m2day, even more particular in a range from 0.15 to less than 0.8 g / m2day.

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