Patent Description:
In the field of construction polymeric sheets, which are often referred to as membranes or panels, are used to protect underground and above ground constructions, such as basements, tunnels, and flat and low-sloped roofs, against penetration water. Waterproofing membranes are applied, for example, to prevent ingress of water through cracks that develop in the concrete structure due to building settlement, load deflection or concrete shrinkage. Roofing membranes are applied on a surface of roof substrate to be waterproofed, such as an insulation board or a cover board in flat and low-sloped roof structures. Waterproofing and roofing membranes are typically delivered to a construction site in form of rolls, transferred to the place of installation, unrolled, and adhered to the substrate to be waterproofed. The substrate on which the membrane is adhered may be comprised of variety of materials depending on the installation site. The substrate may, for example, be a concrete, metal, or wood deck, or it may include an insulation board or recover board and/or an existing membrane.

Commonly used materials for waterproofing and roofing membranes include plastics, in particular thermoplastics such as plasticized polyvinylchloride (p-PVC), thermoplastic olefin elastomers (TPE-O), and elastomers such as crosslinked ethylene-propylene diene monomer (EPDM). Thermoplastic olefin elastomers (TPE-O), also known as thermoplastic polyolefins (TPO), are specific types of heterophasic polyolefin compositions. These are blends of a high-crystallinity "base polyolefin", typically having a melting point of <NUM> or more, and a low-crystallinity or amorphous "polyolefin modifier", typically having a glass transition temperature of -<NUM> or less. The heterophasic phase morphology consists of a matrix phase composed primarily of the base polyolefin and a dispersed phase composed primarily of embedded particles of the polyolefin modifier. Commercially available TPOs include reactor blends of the base polyolefin and the polyolefin modifier as well as physical blends of the base polyolefin and the polyolefin modifier. A reactor blend is typically produced using a sequential polymerization process, wherein the constituents of the matrix phase are produced in a first reactor and transferred to a second reactor, where the constituents of the dispersed phase are produced and incorporated as domains into the matrix phase. Physical blend- type TPOs are produced by melt-blending the base polyolefin with the polyolefin modifier each of which was separately formed prior to blending of the components. Reactor blend-type TPOs are commonly characterized as "in-situ TPOs or "reactor TPOs" or as "heterophasic copolymers".

TPOs have been widely used as materials in providing commercially available roofing membranes due to their numerous advantageous properties. Unlike membranes composed of crosslinked elastomers, TPO membranes are thermoplastic, which enables bonding of the edge portions of overlapped membranes to each other by heat-welding. TPO membranes are also considered to provide an advantage over plasticized PVC membranes, since they are free of environmentally harmful plasticizers. The most significant disadvantage of TPO membranes is that they are less flexible compared to membranes prepared from plasticized PVC or crosslinked elastomers, such as EPDM. The lower flexibility of the TPO membranes is especially pronounced at low temperatures, in particular at temperatures below <NUM>. Membranes having a high flexibility are particularly preferred in roofing applications since they enable easier installation, especially in corner and edge areas.

Flexibility of a TPO-based material can be improved, for example, by increasing the proportion of the low-crystallinity polyolefin modifier component in the blend. However, this approach has been found out to result in increased tackiness of the TPO-material and consequently in increased blocking of the membrane. The blocking of a membrane is generally not desired since it complicates various post-processing steps such as cutting, welding, stacking, and unwinding the membrane from a roll. Another approach taken to increase the flexibility of a TPO-material has been to decrease the crystallinity of the matrix phase of the TPO. These types of TPOs typically exhibit a low flexural modulus but they also have a low softening point, which significantly limits their applicability in roofing applications. Flexibility of a TPO material can also be increased adding of mineral oils as plasticizers into the material. Also these approaches have turned out to be less successful since the mineral oils, even if selected to have a low vapor pressure and high viscosity, tend to migrate over time from the polymer matrix. The migration of the mineral oils renders these types of TPO materials less suitable for use in roofing applications, where the membrane is often exposed to relatively high temperatures, such as in the range of <NUM> to <NUM>. Published patent application <CIT> discloses a highly flexible thermoplastic polymer composition obtained by melt processing blend components including a thermoplastic elastomer (TPE), a non-crosslinked elastomer, and a catalyst, such as zinc oxide. The catalyst is added to the blend to catalyze chain extension and/or crosslinking and/or coupling reactions of the non-crosslinked elastomer during the melt-processing step, which increases the overall complexity of the production process of the polymer composition.

There is thus a need for a novel type of thermoplastic polymer composition, which can be used for providing shaped articles, in particular waterproofing and roofing membranes, exhibiting an improved cold flexibility compared to the State-of-the-Art TPO-based membranes. Furthermore, the novel type of thermoplastic polymer composition should also exhibit low tendency for blocking, excellent mechanical properties, and high stability at elevated temperatures.

The object of the present invention is to provide a thermoplastic composition suitable for use in preparing shaped articles having an improved flexibility, in particular at low temperatures.

It is further an object of the present invention to provide a thermoplastic composition, which is suitable for use in preparing shaped articles, such as waterproofing and roofing membranes, exhibiting low tendency for blocking, excellent mechanical properties, and high stability at elevated temperatures.

It has been surprisingly found out that butene-<NUM> (co)polymers having a high content of butene-<NUM> derived monomer units, in particular of at least <NUM> wt. -%, preferably at least <NUM> wt. - %, can be used to significantly increase the flexibility of a polymer component comprising at least one heterophasic propylene copolymer.

It has also been surprisingly found out that the blending of the above described butene-<NUM> copolymers with heterophasic propylene copolymers enables providing highly filled thermoplastic compositions having a low flexural modulus at a temperature of -<NUM>.

Other subjects of the present invention are presented in other independent claims. Preferred aspects of the invention are presented in the dependent claims.

The subject of the present invention is a thermoplastic composition comprising a polymer component comprising:.

Substance names beginning with "poly" designate substances which formally contain, per molecule, two or more of the functional groups occurring in their names. For instance, a polyol refers to a compound having at least two hydroxyl groups. A polyether refers to a compound having at least two ether groups.

The term "polymer" refers to a collective of chemically uniform macromolecules produced by a polyreaction (polymerization, polyaddition, polycondensation) where the macromolecules differ with respect to their degree of polymerization, molecular weight and chain length. The term also comprises derivatives of said collective of macromolecules resulting from polyreactions, that is, compounds which are obtained by reactions such as, for example, additions or substitutions, of functional groups in predetermined macromolecules and which may be chemically uniform or chemically non-uniform.

The term "α-olefin" designates an alkene having the molecular formula CxH2x (x corresponds to the number of carbon atoms), which features a carbon-carbon double bond at the first carbon atom (α-carbon). Examples of α-olefins include ethylene, propylene, <NUM>-butene, <NUM>-methyl-<NUM>-propene (isobutylene), <NUM>-pentene, <NUM>-hexene, <NUM>-heptene and <NUM>-octene. For example, neither <NUM> ,<NUM>-butadiene, nor <NUM>-butene, nor styrene are referred as "α-olefins" according to the present disclosure.

The term "thermoplastic" refers to any material which can be melted and re-solidified with little or no change in physical properties.

The term "molecular weight" refers to the molar mass (g/mol) of a molecule or a part of a molecule, also referred to as "moiety". The term "average molecular weight" refers to number average molecular weight (Mn) of an oligomeric or polymeric mixture of molecules or moieties. The molecular weight can be determined by conventional methods, preferably by gel permeation-chromatography (GPC) using polystyrene as standard, styrenedivinylbenzene gel with porosity of <NUM> Angstrom, <NUM> Angstrom and <NUM> Angstrom as the column, and tetrahydrofurane as a solvent, at a temperature of <NUM>.

The term "glass transition temperature" (Tg) refers to the temperature above which temperature a polymer component becomes soft and pliable, and below which it becomes hard and glassy. The glass transition temperature (Tg) is preferably determined by dynamical mechanical analysis (DMA) as the peak of the measured loss modulus (G") curve using a rheometer in torsional mode (with cyclic torsional load) with an applied frequency of <NUM> and a strain level (amplitude) of <NUM>%.

The term "softening point" refers to a temperature at which compound softens in a rubber-like state, or a temperature at which the crystalline portion within the compound melts. The softening point is preferably determined by Ring and Ball measurement conducted according to DIN EN <NUM> standard.

The term "melting temperature" refers to a temperature at which a material undergoes transition from the solid to the liquid state. The melting temperature (Tm) is preferably determined by differential scanning calorimetry (DSC) according to ISO <NUM> standard using a heating rate of <NUM>/min. The measurements can be performed with a Mettler Toledo DSC <NUM>+ device and the Tm values can be determined from the measured DSC-curve with the help of the DSC-software. In case the measured DSC-curve shows several peak temperatures, the first peak temperature coming from the lower temperature side in the thermogram is taken as the melting temperature (Tm).

"Comonomer content of a copolymer" refers to the total amount of comonomers in the copolymer given in wt. -% or mol-%. The comonomer content can be determined by IR spectroscopy or by quantitative nuclear-magnetic resonance (NMR) measurements.

The "amount or content of at least one component X" in a composition, for example "the amount of the at least one thermoplastic polymer" refers to the sum of the individual amounts of all thermoplastic polymers contained in the composition. For example, in case the composition comprises <NUM> wt. -% of at least one thermoplastic polymer, the sum of the amounts of all thermoplastic polymers contained in the composition equals <NUM> wt.

The term "room temperature" designates a temperature of <NUM>.

The thermoplastic composition of the present invention is preferably a physical blend of its constituents, i.e. the thermoplastic composition has been obtained by blending the constituents of the thermoplastic composition with each other, wherein each of said constituents was separately formed prior to blending of the constituents.

The thermoplastic composition comprises a polymer component comprising the constituents a), b), and c). The amount of the polymer component in the thermoplastic composition is not particularly restricted and it depends on the intended use of the thermoplastic composition, in particular on the amount of fillers, flame retardants, and other additives contained in the thermoplastic composition. Preferably, the polymer component comprises at least <NUM> wt. -%, more preferably at least <NUM> wt. -%, even more preferably at least <NUM> wt. -%, still more preferably at least <NUM> wt. -% of the total weight of the thermoplastic composition.

According to one or more embodiments, the polymer component comprises <NUM> - <NUM> wt. -%, preferably <NUM> - <NUM> wt. -%, more preferably <NUM> - <NUM> wt. -% of the total weight of the thermoplastic composition. According to one or more further embodiments, the polymer component comprises at least <NUM> wt. -%, preferably at least <NUM> wt. -%, more preferably at least <NUM> wt. -% of the total weight of the thermoplastic composition.

The thermoplastic composition of the present invention comprises at least one butene-<NUM> (co)polymer. The term "(co)polymer" is understood to include homopolymers, copolymers, random copolymers, block copolymers, and terpolymers. The at least one butene-<NUM> (co)polymer can be a homopolymer or a copolymer of butene-<NUM> with one more comonomers (different from butene-<NUM>), preferably one or more α-olefins. Suitable α-olefins present as comonomers in the butene-<NUM> (co)polymer include ethylene, propylene, pentene-<NUM>, hexane-<NUM>, <NUM>-methylpentene and octene-<NUM>. According to one or more embodiments, the at least one butene-<NUM> (co)polymer has a content of butene-<NUM> derived units of at least <NUM> mol-%, preferably at least <NUM> mol-%, more preferably at least <NUM> mol.

The at least one butene-<NUM> (co)polymer contained in the thermoplastic composition of the present invention can be obtained, for example, by using any one of the methods as disclosed in <CIT>. Suitable butene-<NUM> (co)polymers are commercially available, for example, under the trade name of Koattro®, such as Koattro KT MR <NUM> (from Lyondell Basell).

According to one or more embodiments, the at least one butene-<NUM> (co) polymer has:.

According to one or more embodiments, the at least one butene-<NUM> (co)polymer is a homopolymer of butene-<NUM> or a copolymer of butene-<NUM> with one or more α-olefins, preferably selected from the group consisting of ethylene and propylene, wherein the copolymer preferably has a content of comonomer derived units of not more than <NUM> mol-%, preferably not more than <NUM> mol-%, more preferably <NUM> - <NUM> mol-%, even more preferably <NUM> - <NUM> mol-%.

The thermoplastic composition may comprise, in addition to the at least one butene-<NUM> (co)polymer, at least one ethylene-based olefin block copolymer. It goes without saying that the at least one ethylene-based olefin block copolymer is different from the at least one butene-<NUM> (co)polymer.

According to one or more embodiments, the at least one ethylene-based olefin block copolymer is an ethylene - α-olefin block copolymer.

Suitable comonomers for the at least one ethylene - α-olefin block copolymer include, for example, linear and branched α-olefins having <NUM> to <NUM> carbon atoms. According to one or more embodiments, the comonomer in the at least one ethylene - α-olefin block copolymer is selected from the group consisting of propylene, <NUM>-butene, <NUM>-pentene, <NUM>-methyl-<NUM>-butene, <NUM>-hexene, <NUM>-methyl-<NUM>-pentene, <NUM>-methyl-<NUM>-pentene, <NUM>-octene, <NUM>-decene, <NUM>-dodecene, <NUM>-tetradecene, <NUM>-hexadecene, <NUM>-octadecene, and <NUM>-eicosene, preferably form the group consisting of propylene, <NUM>-butene, <NUM>-hexene, and <NUM>-octene.

Preferably, the at least one ethylene - α-olefin block copolymer has a content of ethylene derived units of at least <NUM> wt. -%, preferably at least <NUM> wt. -%, more preferably at least <NUM> wt. According to one or more embodiments, the at least one ethylene - α-olefin block copolymer has a content of ethylene derived units in the range of <NUM> - <NUM> wt. -%, preferably <NUM> - <NUM> wt. -%, more preferably <NUM> - <NUM> wt.

According to one or more embodiments, the at least one ethylene - α-olefin block copolymer has:.

According to one or more embodiments, the at least one ethylene - α-olefin block copolymer is an ethylene - octene block copolymer. Suitable ethylene - octene block copolymers are commercially available, for example, under the trade name of Infuse®, such as Infuse® <NUM>, Infuse® <NUM>, Infuse® <NUM>, Infuse® <NUM>, Infuse® <NUM>, Infuse® <NUM>, and Infuse® <NUM> (all from Dow Chemical Company).

Preferably, the polymer component of the thermoplastic composition comprises at least <NUM> wt. -%, more preferably at least <NUM> wt. -%, even more preferably at least <NUM> wt. -% of the at least one butene-<NUM> (co)polymer and at least <NUM> wt. -%, more preferably at least <NUM> wt. -%, even more preferably at least <NUM> wt. -% of the at least one ethylene-based olefin block copolymer, based on the total weight of the polymer component.

The thermoplastic composition of the present invention further comprises at least one heterophasic propylene copolymer.

Preferably, the at least one heterophasic propylene copolymer comprises:.

wherein the at least one heterophasic propylene copolymer comprises a matrix phase composed primarily of A) and a dispersed phase composed primarily of B).

Preferably, the at least one heterophasic propylene copolymer is a reactor blend of A) and B), wherein the reactor blend has been obtained by using a sequential polymerization process, wherein constituents of the matrix phase are produced in a first reactor and transferred to a second reactor where constituents of the dispersed phase are produced and incorporated as domains into the matrix phase.

Suitable heterophasic propylene copolymers that are commercially available include, for example, the "reactor TPOs" produced with LyondellBasell's Catalloy process technology, which are available under the trade names of Adflex®, Adsyl®, Clyrell®, Hifax®, Hiflex®, and Softell®. Further suitable heterophasic propylene copolymers that are commercially available include, for example, heterophasic ethylene - propylene random copolymers, which are available under the trade name of Borsoft®, such as Borsoft® SD233 CF (from Borealis Polymers).

According to one or more embodiments, the at least one heterophasic propylene copolymer has:.

According to one or more embodiments, the at least one heterophasic propylene copolymer is a heterophasic ethylene - propylene copolymer, preferably having a content of ethylene derived units of not more than <NUM> wt. -%, preferably not more than <NUM> wt. -%, more preferably not more than <NUM> wt. -%, even more preferably not more than <NUM> wt. -%, still more preferably not more than <NUM> wt. -%, most preferably not more than <NUM> wt.

According to one or more embodiments, the at least one heterophasic propylene copolymer comprises at least one heterophasic ethylene - propylene random copolymer. According to one of more embodiments, the at least one heterophasic propylene copolymer is a heterophasic ethylene - propylene random copolymer.

Preferably, the at least one heterophasic propylene copolymer comprises at least <NUM> wt. -%, more preferably at least <NUM> wt. -%, even more preferably at least <NUM> wt. -%, still more preferably at least <NUM> wt. -%, of the total weight of the polymer component of the thermoplastic composition.

The thermoplastic composition further comprises at least one propylene-based elastomer.

Suitable propylene-based elastomers include, in particular, copolymers of propylene and at least one comonomer selected from the group consisting of ethylene and C<NUM>-C<NUM> α-olefins, wherein the copolymer has a content of propylene-derived units of at least <NUM> wt. -%, preferably at least <NUM> wt. -% and a content of units derived from at least one of ethylene or a C<NUM>-C<NUM> α-olefin of <NUM> - <NUM> wt. -%, preferably <NUM> - <NUM> wt.

According to one or more embodiments, the at least one propylene-based elastomer is propylene - ethylene copolymer having a content of propylene derived units of <NUM> - <NUM> wt. -%, preferably <NUM> - <NUM> wt. -% and a content of ethylene derived units of <NUM> - <NUM> wt. -%, preferably <NUM> - <NUM> wt.

According to one or more embodiments, the at least one propylene-based elastomer has:.

According to one or more embodiments, the at least one propylene-based elastomer comprises at least <NUM> wt. -%, preferably at least <NUM> wt. -%, more preferably at least <NUM> wt. -%, even more preferably at least <NUM> wt. -%, of the total weight of the polymer component of the thermoplastic composition.

According to one or more embodiments, the weight ratio of the amount of the at least one heterophasic propylene copolymer to the amount of the at least one propylene-based elastomer is from <NUM>:<NUM> to <NUM>:<NUM>, preferably from <NUM>:<NUM> to <NUM>:<NUM>, more preferably from <NUM>:<NUM> to <NUM>:<NUM>, even more preferably from <NUM>:<NUM> to <NUM>:<NUM>, still more preferably from <NUM>:<NUM> to <NUM>.

According to one or more embodiments, the polymer component of the thermoplastic composition comprises the at least one butene-<NUM> (co)polymer and the at least one heterophasic propylene copolymer, wherein the at least one butene-<NUM> (co)polymer preferably comprises at least <NUM> wt. -%, preferably at least <NUM> wt. -%, more preferably at least <NUM> wt. -%, such as <NUM> - <NUM> wt. -%, preferably <NUM> - <NUM> wt. -%, more preferably <NUM> - <NUM> wt. -%, even more preferably <NUM> - <NUM> wt. -%, still more preferably <NUM> - <NUM> wt. -%, most preferably <NUM> - <NUM> wt. -% of the total weight of the polymer component, wherein the polymer component preferably comprises at least <NUM> wt. -%, more preferably at least <NUM> wt. -%, even more preferably at least <NUM> wt. -%, still more preferably at least <NUM> wt. -% of the total weight of the thermoplastic composition.

According to one or more embodiments, the polymer component of the thermoplastic composition comprises the at least one ethylene-based olefin block copolymer and the at least one heterophasic propylene copolymer, wherein the at least one ethylene-based olefin block copolymer preferably comprises at least <NUM> wt. -%, more preferably at least <NUM> wt. -%, even more preferably at least <NUM> wt. -%, such as <NUM> - <NUM> wt. -%, preferably <NUM> - <NUM> wt. -%, more preferably <NUM> - <NUM> wt. -%, even more preferably <NUM> - <NUM> wt. -%, still more preferably <NUM> - <NUM> wt. -%, most preferably <NUM> - <NUM> wt. -% of the total weight of the polymer component, wherein the polymer component preferably comprises at least <NUM> wt. -%, more preferably at least <NUM> wt. -%, even more preferably at least <NUM> wt. -%, still more preferably at least <NUM> wt. -% of the total weight of the thermoplastic composition.

According to one or more embodiments, the polymer component of the thermoplastic composition is composed of the at least one butene-<NUM> (co)polymer, the at least one heterophasic propylene copolymer, and the at least one propylene-based elastomer, wherein the polymer component preferably comprises:.

Preferably, the thermoplastic composition is not tacky at a temperature of <NUM>. The term "tacky" refers in the present disclosure to a surface tack in the sense of instantaneous adhesion or stickiness that is preferably sufficient so that, when pressed with a thumb, exerting a pressure of <NUM> for <NUM> second on the surface of the composition, the thumb remains sticking to the surface of the composition, preferably such that a composition having an intrinsic weight of <NUM> can be lifted up for at least <NUM> seconds.

According to one or more embodiments, the thermoplastic composition is substantially free of tackifying resins. The term "tackifying resin" designates in the present disclosure resins that in general enhance the adhesion and/or tackiness of a composition. Typical tackifying resins include synthetic resins, natural resins, and chemically modified natural resins having a relatively low average molecular weight (Mn), such as not more than <NUM>'<NUM>/mol, in particular not more than <NUM>'<NUM>/mol. The expression "essentially free of tackifying resins" is understood to mean that the amount of tackifying resins is preferably less than <NUM> wt. -%, more preferably less than <NUM> wt. -%, even more preferably less than <NUM> wt. -%, still more preferably less than <NUM> wt. -%, based on the total weight of the thermoplastic composition.

According to one or more embodiments, the thermoplastic composition further comprises at least one flame retardant. These may be needed, in particular, in case the thermoplastic composition is used for preparing roofing membranes.

According to one or more embodiments, the at least one flame retardant comprises <NUM> - <NUM> wt. -%, preferably <NUM> - <NUM> wt. -%, more preferably <NUM> - <NUM> wt. -%, even more preferably <NUM>-<NUM> wt. -%, still more preferably <NUM> - <NUM> wt. -% of the total weight of the thermoplastic composition. The at least one flame retardant, if used, is preferably selected from the group consisting of magnesium hydroxide, aluminum trihydroxide, antimony trioxide, ammonium polyphosphate, and melamine-, melamine resin-, melamine derivative-, melamine-formaldehyde-, silane-, siloxane-, and polystyrene-coated ammonium polyphosphates.

Other suitable flame retardants include, for example, <NUM>,<NUM>,<NUM>-triazine compounds, such as melamine, melam, melem, melon, ammeline, ammelide, <NUM>-ureidomelamine, acetoguanamine, benzoguanamine, diaminophenyltriazine, melamine salts and adducts, melamine cyanurate, melamine borate, melamine orthophosphate, melamine pyrophosphate, dimelamine pyrophosphate and melamine polyphosphate, oligomeric and polymeric <NUM>,<NUM>,<NUM>-triazine compounds and polyphosphates of <NUM>,<NUM>,<NUM>-triazine compounds, guanine, piperazine phosphate, piperazine polyphosphate, ethylene diamine phosphate, pentaerythritol, borophosphate, <NUM>,<NUM>,<NUM>-trihydroxyethylisocyanaurate, <NUM>,<NUM>,<NUM>-triglycidylisocyanaurate, triallylisocyanurate and derivatives of the aforementioned compounds.

Suitable flame retardants are commercially available, for example, under the trade name of Martinal® and Magnifin® (both from Albemarle) and under the trade names of Exolit® (from Clariant), Phos-Check® (from Phos-Check) and FR CROS® (from Budenheim).

According to one or more embodiments, the at least one flame retardant has a median particle size d<NUM> of not more than <NUM>, preferably not more than <NUM>, more preferably not more than <NUM>, even more preferably not more than <NUM>. The term "median particle size d<NUM>" refers to a particle size below which <NUM>% of all particles by mass are smaller than the d<NUM> value. The term "particle size" refers in the present disclosure to the area-equivalent spherical diameter of a particle. The particle size distribution can be determined by laser diffraction method as described in ISO <NUM>:<NUM> standard.

The thermoplastic composition can further comprise one or more auxiliary compounds, such as UV- and heat stabilizers, antioxidants, plasticizers, fillers, dyes, and pigments, such as titanium dioxide and carbon black, matting agents, antistatic agents, impact modifiers, biocides, and processing aids such as lubricants, slip agents, antiblock agents, and denest aids. The total amount of these auxiliary components is preferably not more than <NUM> wt. -%, more preferably not more than <NUM> wt. -%, even more preferably not more than <NUM> wt. -%, still more preferably not more than <NUM> wt. -%, based on the total weight of the thermoplastic composition.

Suitable fillers to be used in the thermoplastic composition include, for example, inert mineral fillers. The term "inert mineral filler" designates in the present disclosure mineral fillers, which, unlike mineral binders do not undergo a hydration reaction in the presence of water.

Suitable inert mineral fillers include, for example, sand, granite, calcium carbonate, clay, expanded clay, diatomaceous earth, pumice, mica, kaolin, talc, dolomite, xonotlite, perlite, vermiculite, Wollastonite, barite, magnesium carbonate, calcium hydroxide, calcium aluminates, silica, fumed silica, fused silica, aerogels, glass beads, hollow glass spheres, ceramic spheres, bauxite, comminuted concrete, and zeolites.

The inert mineral fillers, if used, are preferably present in the thermoplastic composition in form of solid particles, preferably having a d<NUM> particle size of not more than <NUM>, more preferably not more than <NUM>, even more preferably not more than <NUM>, still more preferably not more than <NUM>. The term "d<NUM> particle size" refers to a particle size below which <NUM>% of all particles by mass are smaller than the d<NUM> value.

One of the advantages of the thermoplastic composition of the present invention is that a shaped article consisting of the thermoplastic composition exhibits low blocking behavior, which enables unproblematic post-processing of the substrate layer, such as cutting, welding, stacking, and unwinding from a roll. According to one or more embodiments, a shaped article composed of the thermoplastic composition of the present invention has a blocking value, determined by means of the method as described below, of not more than <NUM> N/<NUM>, preferably not more than <NUM> N/<NUM>, more preferably not more than <NUM> N/<NUM>.

The blocking value is determined based on the measurement method as defined in DIN <NUM> standard. The measurement is conducted at a temperature of <NUM> using a peeling mode instead of a shearing mode, i.e. the tested sheets are separated from each other by using a peeling force. The blocking value is determined as force in N/<NUM> width of sheet required to separate the two sheets from each other after the sheets have been pressed together for a period of <NUM> hours at a temperature of <NUM> using a pressure of <NUM>/cm<NUM>.

Another advantage of the thermoplastic composition of the present invention is that the increased cold flexibility can be achieved without having a negative impact on other mechanical properties, such as elongation at break and resistance to impact.

According to one or more embodiments, a shaped article composed of the thermoplastic composition of the present invention has an elongation at break, determined according to ISO <NUM>-<NUM> standard at a temperature of <NUM> using a cross head speed of <NUM>/min, of at least <NUM>%, preferably of at least <NUM>%, more preferably at least <NUM>% and/or a resistance to impact, determined according to EN <NUM> type A standard, of at least <NUM>, preferably at least <NUM> and/or a resistance to impact, determined according to EN <NUM> type B standard, of at least <NUM>, preferably at least <NUM>. The elongation at break and resistance to impact are measured with a shaped article composed of the thermoplastic composition of the present invention and having a thickness of <NUM>.

The preferences given above for the at least one butene-<NUM> (co)polymer, the at least one ethylene-based block copolymer, the at least one heterophasic propylene copolymer, the at least one propylene-based elastomer, and the at least one flame retardant apply equally to all subjects of the present invention unless stated otherwise.

Another subject of the present invention is use of the thermoplastic composition according to the present invention for producing a shaped article, preferably a waterproofing membrane or a roofing membrane, in particular a roofing membrane.

The thermoplastic composition of the present invention has been found out to be particularly suitable for use in producing of roofing membranes since the composition exhibits a high flexibility, in particular at low temperatures. Furthermore, since the improved cold flexibility can be achieved without the use of rubbers or mineral oils, the thermoplastic composition of the present invention also exhibits a low tendency for blocking as well as a high stability at elevated temperatures.

Another subject of the present invention is a shaped article comprising a substrate layer, wherein the substrate layer comprises or is essentially composed of the thermoplastic composition according to the present invention.

According to one or more embodiments, the substrate layer is a sheet-like element having a first major surface and a second major surface separated from the first major surface by a thickness there between. Preferably, sheet-like element has a length and width at least <NUM> times, preferably at least <NUM> times, more preferably at least <NUM> times greater than the thickness of the element.

According to one or more embodiments, the substrate layer has a thickness, determined according to the DIN EN <NUM>-<NUM> standard, of <NUM> - <NUM>, preferably <NUM> - <NUM>, more preferably <NUM> - <NUM>, even more preferably <NUM> - <NUM>, still more preferably <NUM> - <NUM>, such as <NUM> - <NUM>.

The shaped article may further comprise a reinforcing layer. The reinforcing layer may be fully embedded into the substrate layer or directly or indirectly adhered to one of the major surfaces of the substrate layer. The expression "fully embedded" is understood to mean that the reinforcing layer is fully covered by the matrix of the substrate layer. The expression "directly adhered" is understood to mean that no further layer or substance is present between the layers and that the opposing surfaces of the layers are directly adhered to each other. At the transition area between the two layers, the materials of the layers can also be present mixed with each other. The reinforcing layer and the substrate layer can be indirectly adhered to each other, for example, via a connecting layer, such as a layer of adhesive.

The type of the reinforcing layer, if used, is not particularly restricted. For example, the reinforcing layers commonly used for improving the dimensional stability of roofing membranes can be used. Preferable reinforcing layers include non-woven fabrics, woven fabrics, and non-woven scrims, and combinations thereof.

The term "non-woven fabric" designates in the present disclosure materials composed of fibers, which are bonded together by using chemical, mechanical, or thermal bonding means, and which are neither woven nor knitted. Non-woven fabrics can be produced, for example, by using a carding or needle punching process, in which the fibers are mechanically entangled to obtain the nonwoven fabric. In chemical bonding, chemical binders such as adhesive materials are used to hold the fibers together in a non-woven fabric.

The term "non-woven scrim" refers in the present disclosure web-like non-woven products composed of yarns, which lay on top of each other and are chemically bonded to each other. Typical materials for non-woven scrims include metals, fiberglass, and plastics, in particular polyester, polypropylene, polyethylene, and polyethylene terephthalate (PET).

According to one or more embodiments, the reinforcing layer is composed of synthetic organic fibers, preferably selected from the group consisting of polyester fibers, polypropylene fibers, polyethylene fibers, nylon fibers, and polyamide fibers. According to one or more further embodiments, the reinforcing layer is composed of inorganic fibers, preferably selected from the group consisting of glass fibers, aramid fibers, wollastonite fibers, and carbon fibers, more preferably glass fibers.

According to one or more embodiments, the reinforcing layer has been thermally laminated to one of the major surfaces of the substrate layer in a manner that gives direct bonding between the reinforcing layer and the substrate layer. The term "thermal lamination" refers to a process, in which the layers are bonded to each by the application of thermal energy. In particular, the term "thermal lamination" refers to a process comprising partially melting at least one of the layers upon application of thermal energy followed by a cooling step, which results in formation of a physical bond between the layers without using an adhesive.

Another subject of the present invention is a method for producing a shaped article, the method comprising steps of:.

Suitable extrusion apparatuses comprising at least one extruder and an extruder die are well known to a person skilled in the art. Any conventional extruders, for example, a ram extruder, single screw extruder, or a twin-screw extruder may be used. Preferably, the extruder is a screw extruder, more preferably a twin- screw extruder. The constituents of the thermoplastic composition may be fed to the extruder as individual streams, as a pre-mix, a dry blend, or as a master batch.

Another subject of the present invention is a method for covering a substrate, the method comprising steps of:.

According to one or more embodiments, the substrate that is covered with the sealing devices is a roof substrate, preferably an insulation board, a cover board, or an existing roofing membrane.

Step III) of the method for covering a substrate can be conducted manually, for example by using a hot air tool, or by using an automatic welding device, such as an automatic hot-air welding device, for example Sarnamatic® <NUM> welding device. The temperature to which the edge region of the second shaped article and the overlapped section of the first shaped article are heated depends on the embodiment of the first and second shaped articles and also whether the step III) is conducted manually or by using an automatic welding device. Preferably, the edge region of the second shaped article and the overlapped section of the first shaped article are heated to a temperature of at or above <NUM>, more preferably at or above <NUM>.

Still another subject of the present invention is a waterproofed structure obtained by using the method for covering a substrate.

The followings materials were used in the examples:.

The shaped articles (sheets) were produced using a laboratory scale extrusion-calendering apparatus consisting of a twin screw extruder (Berstorff GmbH), a flat die and set of water-cooled calender rolls.

In producing of the shaped articles, the constituents of the thermoplastic composition as shown in Table <NUM> were fed to the extruder hopper. The blend was melt-processed in the extruder and extruded through a flat die into single ply sheets having a thickness of approximately <NUM>. The extrusion was conducted using an extrusion temperature of ca.

Flexibility of the shaped articles was determined by measuring the storage modulus (G') of the test specimen at temperatures of -<NUM>, <NUM>, and +<NUM>. The storage moduli were measured by dynamical mechanical analysis (DMA) using a method based on ISO <NUM>-<NUM>:<NUM> standard and.

The values of the storage moduli (G') presented in Table <NUM> have been obtained with test specimen, which were cut from the shaped articles in a lengthwise direction.

The tensile strength at break and the elongation at break were measured according to ISO <NUM>-<NUM> standard at a temperature of <NUM> using a cross head speed of <NUM>/min.

The values presented in Table <NUM> have been obtained with test specimen, which were cut from the shaped articles in a lengthwise direction.

Claim 1:
A thermoplastic composition comprising a polymer component comprising:
a) At least one butene-<NUM> (co)polymer,
b) At least one heterophasic propylene copolymer, and
c) At least one propylene-based elastomer, wherein the at least one butene-<NUM> (co)polymer has a content of butene-<NUM> derived units of at least <NUM> wt.-%, preferably at least <NUM> wt.-%.