Thermoplastic molding material with improved performance properties

Abstract

The present invention relates to a thermoplastic molding material comprising a styrene block copolymer and a propylene-based copolymer, wherein the SBC polymer comprises a styrene content of 5 to 40 wt.-% and the weight average molecular weight Mw of the main chain of the propylene copolymer is in the range of 10 w <10000 g / mol. Due to its melt viscosity and mechanical properties, the thermoplastic molding material is suitable for immobilizing particles.

Description

[0001] field

[0002] The present invention relates to thermoplastic molding materials with improved mechanical properties for use in or as sprayable structure-forming hot-melt adhesives, comprising a styrene block copolymer (SBC) and a propylene-based polymer, optionally grafted with styrene or a carboxylic anhydride.

[0003] The thermoplastic molding materials according to the invention and the hotmelt adhesives based thereon are suitable for bonding substrates to one another or for fixing powders or granules to any type of substrate, wherein, in addition to the thermoplastic molding materials according to the invention, the hotmelt adhesives may also contain tackifiers, plasticizers, organic or inorganic pigments, fillers, flame retardants, stabilizers, antistatic agents, antioxidants and light stabilizers.

[0004] background

[0005] Hot melt adhesives are thermoplastic compositions that are solid at room temperature. When being converted into liquid or molten state by heating, hot melt adhesives are open, and hot melt adhesives can be applied on substrates. When a second substrate is applied on the hot melt adhesive before the hot melt adhesive is cooled to solid state again, an adhesive bonding of two substrates can be formed. Hot melt adhesives have an open time optimized for intended use, and realize the permanent adhesive bonding of adherends. Hot melt adhesives typically comprise a viscous base polymer, an adhesive tackifier and optional wax, plasticizer (oil) and other additives. Typical hot melt adhesives and functions thereof have been described in US 5,026,756.

[0006] The adhesive base polymers used are polymers such as natural and synthetic rubbers; polyacrylates; polyisobutylene; one or more polyolefins; polyesters; polychloroprene; polyvinyl ethers; polyurethanes; styrene block copolymers (SBCs), including block copolymers of styrene-butadiene-styrene (SBS), styrene-isoprene-styrene (SIS), styrene-isoprene-butadiene-styrene (SIBS), styrene-ethylene-butadiene-styrene (SEBS), styrene-ethylene-propylene (SEP) or styrene-ethylene-propylene-styrene (SEPS). These base polymers are generally responsible for the adhesive effect of the adhesive system.

[0007] The adhesive effect of hot melt adhesives is mainly determined by the tackifier, which is usually or contains resins. These resins are low molecular weight products such as C5- or C9-streams from crude oil processing, usually contain aromatics and usually have a glass transition temperature above room temperature.

[0008] Therefore, incorporating resins into hot melt adhesive formulations increases the glass transition temperature of the formulation, so that the low-temperature flexibility of such hot melt adhesives is reduced and the temperature range in which the hot melt adhesives can be used is limited.

[0009] Also used as resins are polyterpene resins, natural and modified rosin resins, in particular resin esters, glycerol esters of wood resins, phenol-modified pentaerythritol esters, and phenol-modified terpene resins. These resin types contain substances with irritants / health concerns, such as abietic acid, and can cause allergies, making their use in hygiene, food packaging, and medical applications problematic.

[0010] In some cases, the density of the resin is typically greater than 1 g / cm 3 As a result, the use of such resins in hot melt adhesive formulations leads to increased density, particularly in formulations containing polyolefins as the adhesive base polymer. This means that for a constant application volume, more weight of hot melt adhesive is required, which is both a negative cost factor and results in a higher weight of the bonded substrate.

[0011] Plasticizers in hot melt adhesive formulations reduce the viscosity of the adhesive composition, thereby improving its processability and ease of use. Hot melt adhesives, especially those based on SBCs, often contain mineral oil as a plasticizer, in some cases in considerable amounts.

[0012] Mineral oil is based on crude oil and therefore contains paraffins, cycloparaffins, aromatic and polycyclic compounds, as well as volatile organic compounds (VOCs), which contribute to indoor air pollution. These compounds, also known as mineral oil-based saturated hydrocarbons (MOSHs) and mineral oil-based aromatic hydrocarbons (MOAHs), are classified as toxicologically hazardous due to their tendency to accumulate in human tissues. Mineral oils are generally poorly integrated into hot melt adhesive formulations, resulting in an increased tendency to migrate.

[0013] Hot melt adhesives have a wide variety of possible uses. They are particularly suitable for permanent adhesive bonding. Since they are applied from the melt, hot melt adhesives can avoid solvents.

[0014] Since many hot melt adhesives are often used in direct contact with the human body or in everyday products, it is advantageous when the hot melt adhesives are free of mineral oil and require the lowest possible resin proportions, whereby they exhibit improved environmental friendliness and lower toxicology and can be produced in a sustainable manner.

[0015] The processing of hot melt adhesives, in particular their application to the relevant substrates, can be achieved via a variety of methods, such as spraying, extrusion application, application with the aid of a roller, beads or slot die. In order to be optimally suited to the various application methods, the hot melt adhesive must have rheological properties that are suitable for the application method.

[0016] Spraying is a common application technique in hot melt adhesive technology. In rotary spraying, a stream of melt exits the nozzle, optionally extended by an air stream without tearing, and is then deposited onto the substrate in a spiral pattern. Application temperatures range from 150°C to 250°C, depending on the material. Conventional hot melt adhesive formulations based on SBCs and polyolefins are difficult to spray at temperatures above 160°C. Unfavorable spray patterns lead to severe limitations in areas of application. Higher application temperatures increase energy consumption and premature aging of the adhesive, resulting in mechanical damage.

[0017] EP 3 271 436 (Henkel) discloses a sprayable hot melt adhesive based on polyolefins and an absorbent article comprising the adhesive. The sprayable hot melt adhesive based on polyolefins is particularly suitable for spraying at low application temperatures. The sprayable hot melt adhesive with low application temperature allows for thin adhesive bonding of heat-sensitive substrates. The document does not relate to the mechanical properties of the hot melt adhesive.

[0018] Sprayable hot melt adhesive compositions are mainly in the low viscosity range, so they can be applied using this application technology. The low melt viscosity of sprayable hot melt adhesives is usually relevant with insufficient mechanical properties, which can have a negative impact on the viscous properties of the material. These include properties such as the elongation at break, resilience or strength of the material in particular. This substrate applied by spraying can usually only withstand low mechanical stress. They are optimized to ensure the most uniform and material-efficient coating to the substrate to be bonded. Priority is given to the adhesive bonding of the substrate, while, by contrast, viscous polymers are intended to ensure sufficient stability to prevent the adhesive bonding itself from becoming brittle. The elasticity of the adhesive bonding only plays a minor role here. Although hot melt adhesives with higher melt viscosity can be made sprayable by increasing the application temperature, this temperature increase causes energy consumption to increase and may cause undesirable heat-induced degradation of the components used.

[0019] The possibility of formulating hot-melt adhesives based on polyolefins with an SBC component is known from the prior art.

[0020] WO 2006 / 020309 (Exxon) describes a polymer composition comprising at least one component that is a polymer derived from propylene units and at least one component that is a styrene block copolymer. The polymer composition exhibits processing properties suitable for a variety of applications, such as films, fibers, fabrics and nonwovens, sheets, moldings, extruded parts, thermoformed objects, and the like. However, spray application is not described because the claimed system has a melt viscosity that is too high for this application technique.

[0021] EP 3 453 408 (Fuller) relates to a hot melt adhesive composition comprising a first propylene-based polymer having a Mw of no greater than about 75,000 and a polydispersity index of less than about 5, and a second polymer which is a hydrogenated styrene block copolymer having a styrene content of no greater than about 20% and a melt flowability of no greater than about 25 g / 10 min as tested according to ASTM 1238 (230° C., 5 kg), wherein the adhesive composition contains 10% to 18% by weight of a plasticizer. Propylene-based polymers having a weight average molecular weight of less than 10,000 g / mol are not explicitly disclosed.

[0022] Effective formulation of hot melt adhesives can be challenging because many polymers used in hot melt adhesive formulations—particularly those with reduced amounts of tackifiers and plasticizers—are only partially miscible due to incompatibility issues between the different polymers. The components are miscible to a large extent, however, the miscibility achieved is insufficient to achieve a completely homogeneous mixture.

[0023] P. Galli, T. Simonazzi, D. Del Duca; Acta Polym. 39 (1988) 81 explain that most polymers cannot mix with each other due to the low entropy of their mixtures. The mechanical properties of a blend or formulation depend not only on its composition but also on the degree of dispersion, phase shape, and interactions between the blend phases. By controlling the morphology, the blend properties can be controlled.

[0024] Various efforts have been made in the prior art to improve the compatibility of different polymers, such as polyolefins and polystyrene, by using various compatibilizers.

[0025] Grafted polymers are also known as compatibilizers.

[0026] A comprehensive overview of the possibilities for modifying polypropylene by grafting reactions is given in RM Ho, AC Su, CH Wu; Polymer 34 (1993) 3264. A disadvantage of all the syntheses described is the inhomogeneity of the resulting graft copolymers and the formation of ungrafted fractions, which makes the characterization of their molecular structure and the description of uniform properties difficult.

[0027] Therefore, miscibility issues have been addressed through available solutions, such as block copolymers, which are used to address compatibility issues. SBC block copolymers combine the properties of polymers such as PS and PP / PE, are more defined and reliable in production and performance, and have therefore been the preferred solution to the compatibility issue.

[0028] Other compatibilizer routes have not been pursued extensively in the prior art, as there is no need to improve the miscibility and thus the mechanical properties of the polymer blend mixture.

[0029] Until today, the compatibility of SBCs and propylene-based polymers has not been considered in depth, as fairly miscible mixtures of these components can be provided.

[0030] In the prior art, there are only a few examples of compatibilization concepts based on grafted polymers applied to hot melt adhesives.

[0031] The invention of US 5,461,111 (Shell) provides a rigid thermoplastic composition comprising about 60-95 wt% of a polymer component of a graft copolymer comprising about 10-65 wt% of a graft copolymer of a styrene polymer grafted onto a backbone of a propylene material, and about 40-5 wt% of a polymer component of a rubber component comprising (1) about 20-100 wt% of a selectively hydrogenated block copolymer having weak styrene domains and about 80-0 wt% of an olefin copolymer rubber, such as an EPM (ethylene-propylene monomer rubber). The rigid composition has significantly improved toughness and melt viscosity and is not assumed to exhibit low viscosity and sprayability. The mechanical properties of the rigid thermoplastic composition are not described.

[0032] US 7,439,305 (Henkel) relates to a novel polyolefin based on at least one aromatic modified polyethylene and / or polypropylene (co)polymer, another ethylene or propylene / C4 to C 29 A hot melt adhesive comprising an α-olefin copolymer, at least one tackifying resin, a wax, and additives. The polyolefin and aromatic-modified polyolefin have a molecular weight Mn between 1,000 and 50,000 g / mol. Melting enthalpy and pour point are not disclosed. The teachings of this application do not consider mechanical properties relevant to specific applications of the hot melt adhesive.

[0033] However, the compatibility levels achieved so far are not sufficient for specialized applications requiring high mechanical stability of small amounts of polymer, such as thin polymer fibers.

[0034] The current trend is towards sprayable hot melt adhesives that form stable web structures for hygienic applications.

[0035] DE 11 2016 001 247 (Procter & Gamble) relates to an absorbent structure for an absorbent article, comprising a first substrate and an absorbent layer supported thereon. The absorbent layer comprises an absorbent material which in turn comprises a superabsorbent polymer material, wherein the absorbent structure comprises a mesh structure for at least partially fixing the absorbent layer to the first substrate. The mesh structure has a storage modulus (G') of greater than 1.2 × 10 at 21°C. 6Pa. The weight average molecular weight Mw of the thermoplastic polymer composition is greater than 10000 g / mol. No explicit mixtures of SBC and propylene-based polymers are described.

[0036] WO2017 / 132119 (Procter & Gamble) discloses a superabsorbent immobilizing agent comprising at least 50% by weight of one or more polymers, each having a peak molecular weight of at least 10 kg / mol. The polymers are selected from polymers and copolymers of propylene, ethylene, butene, and combinations thereof; styrene block copolymers; polyolefins; olefin block copolymers, and combinations thereof.

[0037] Using hot-melt adhesive formulations based on polyolefins, it has hitherto been impossible to produce stable network structures for fixing spatially expanding and re-contracting particles, as suitable formulations with the mechanical properties that are crucial for this application could not be produced.

[0038] The object of the present invention is to overcome the problems described in the prior art and to provide an improved sprayable hot melt adhesive having a well-balanced ratio of mechanical properties that can be applied using energy-efficient and material-efficient application techniques, while still ensuring high mechanical stability and flexibility of the adhesive bond, thereby opening up possible applications that place higher demands on the stability of the adhesive bond. In particular, the application of adhesive webs by spraying can be mentioned, which fixes particles or powders without impairing mass transfer with the environment and can also stabilize expanding and contracting systems by liquid absorption. SUMMARY OF THE INVENTION

[0040] According to the invention, this object is achieved by a thermoplastic molding material comprising

[0041] (a) at least one styrene block copolymer (SBC) having a styrene content of 5 to 40% by weight, preferably 10 to 35% by weight, particularly preferably 20 to 35% by weight, based on the total mass of the SBC, and

[0042] (b) one or more propylene-based polymers (PbP) having a PbP backbone weight-average molecular weight M w less than 10,000 g / mol, preferably less than 9,000 g / mol, particularly preferably less than 7,000 g / mol (PbP-ng),

[0043] Therein, PbP preferably has a melting enthalpy measured in accordance with ISO 11357-2 of less than 50 J / g, preferably less than 30 J / g, particularly preferably from 0 to 5 J / g, most particularly preferably 0 J / g.

[0044] PbP with a melting enthalpy of 0 J / g has no crystallinity.

[0045] In a preferred embodiment of the present invention, one or more propylene-based polymers (PbP-ng) are grafted with 1 to 50% by weight, preferably 3 to 30% by weight, particularly preferably 5 to 20% by weight, of vinylaromatic monomers (PbP-g-VAM), preferably styrene and its derivatives (PbP-g-ST), based on the total weight of the PbP backbone.

[0046] In another preferred embodiment of the present invention, one or more propylene-based polymers (PbP-ng) are grafted with 0.1 to 20% by weight, preferably 0.5 to 15% by weight, particularly preferably 1 to 10% by weight, of unsaturated vinyl monomers containing heteroatoms (PbP-g-UVMH), preferably carboxylic anhydrides, particularly preferably maleic anhydride (PbP-g-MA), based on the total weight of the PbP backbone.

[0047] BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The manner of implementing certain features will become more apparent and the disclosure itself will be better understood by reference to the following description of example forms of the disclosure taken in conjunction with the accompanying drawings, in which Figure 1 Shown are dumbbell-shaped test specimens used to measure certain mechanical properties of thermoplastic molding materials.

[0049] Detailed description

[0050] definition

[0051] Propylene-based polymer (PbP) in the context of the present invention refers to low molecular weight, linear propylene homopolymers or copolymers produced using Ziegler or metallocene catalysts, which have a propylene content of at least 50 wt. % or more.

[0052] PbP encompasses both: ungrafted PbP (PbP-ng); and PbP grafted with (i) a vinyl aromatic monomer (PbP-g-VAM), including an embodiment equivalent to PbP grafted with styrene (PbP-g-ST) or (ii) PbP grafted with an unsaturated vinyl monomer containing a heteroatom (PbP-g-UVMH), such as PbP grafted with maleic anhydride (PbP-g-MA). The term PbP-g-VAM used in this application corresponds to / is equivalent to the term PbP-g-St defined in U.S. Provisional 62 / 966,394, from which priority is claimed. If this application refers only to ungrafted PbP, it will be referred to as ungrafted PbP (PbP-ng).

[0053] In the context of the present invention, PbP-backbone refers to linear PbP produced using Ziegler or metallocene catalysts and without substitution at the grafting sites. The term PbP-backbone can technically be replaced by the term PbP-ng, but both terms are used to clarify the functionality of the polymer for those skilled in the art.

[0054] The PbP-ng used in the thermoplastic molding materials according to the invention are described, for example, in WO 2018 / 0073088, where they are a component of a non-sprayable, permanently tacky pressure-sensitive adhesive.

[0055] The use of PbP in the thermoplastic molding materials according to the invention ensures better integration thereof into the SBC matrix, resulting in reduced migration (“bleeding”) and reduced formation of volatile organic compounds (“VOCs”).

[0056] PbP-g-VAM or PbP-g-UVMH is prepared by grafting reaction of PbP-ng as described according to the following method:

[0057] Suitable starting materials for the production of PbP-g-VAM or PbP-g-UVMH are those produced using Ziegler or metallocene catalysts and having a weight average molecular weight M w PbP-ng of less than 10,000 g / mol. Preferred PbP-ng have a melt viscosity of between 20 and 1,000 mPa.s at 170°C, such as PbP. Particularly preferred PbP-ng are low molecular weight propylene homopolymers or copolymers characterized by a statistical distribution of the comonomers and a low degree of crystallinity and a predominantly to completely atactic structure of the polypropylene portion obtained by using a metallocene catalyst system.

[0058] Suitable materials preferably comprise propylene and one or more selected from ethylene and C4-C 18 Other monomers of higher α-olefins: PbP-ng particularly preferably comprises propylene and ethylene.

[0059] Vinyl aromatic monomers (VAM), such as styrene, or styrene derivatives substituted in the ring and having linear or branched alkyl substituents, such as α-methylstyrene, p-tert-butylmethylstyrene, 1,3-dimethylstyrene, or alkoxylated styrene derivatives, are suitable as grafting components. Styrene and its derivatives are preferred, and styrene is particularly preferred. The VAM component is used in an amount of 0.1 to 50% by weight of the starting material.

[0060] Unsaturated vinyl monomers containing heteroatoms (UVMH), preferably carboxylic anhydrides, particularly preferably maleic anhydride (MA), are suitable as grafting components. The UVMH component is used in an amount of 0.1 to 20% by weight of the starting material.

[0061] Suitable free radical initiators are components which decompose under the reaction conditions to a sufficient extent into free radicals, for example organic peroxides, such as alkyl-, aryl- or acyl- peroxides, for example di-tert-butyl peroxide, dibenzoyl peroxide or dicumyl peroxide, peroxy esters such as tert-butyl peracetate or tert-butyl perbenzoate and hydroperoxides, for example tert-butyl hydroperoxide or cumene hydroperoxide. Other possible free radical initiators are aliphatic azo compounds, for example azo-bis-(2-methylpropanenitrile) or 2,2'-azo-bis-(2,4-dimethylpentanenitrile). Preference is given to dialkyl peroxides. Particular preference is given to di-tert-butyl peroxide. The amount of free radical initiator is from 0.1 to 50% by weight of PbP.

[0062] The reaction of PbP with the grafting component can take place continuously or discontinuously. In a discontinuous process, the PbP-ng is heated to a temperature above the melting temperature of the PbP-ng, preferably between 100°C and 200°C, particularly preferably between 130°C and 180°C, and the grafting component and the free radical initiator are added continuously, with stirring, over a sufficient period of time, or in one or more portions, and, if applicable, under an inert gas atmosphere. After the dosing is complete, a post-reaction can be carried out at the same or a different temperature, optionally after the addition of an additional amount of free radical initiator. Volatile components produced during the reaction or excess volatile starting materials can be separated off under vacuum and / or by stripping with an inert gas.

[0063] Such modified PbP-ngs grafted with (i) a vinyl aromatic monomer: for example styrene or a styrene derivative substituted in the ring and having straight-chain or branched alkyl substituents, for example a-methylstyrene, p-tert-butylmethylstyrene, 1,3-dimethylstyrene or an alkoxylated styrene derivative (PbP-g-VAM), preferably PbP-g-ST or grafted with (ii) an unsaturated vinyl monomer comprising a heteroatom, for example a carboxylic anhydride (PbP-g-UVMH), preferably maleic anhydride PbP-g-MA have a wide range of possible applications as compatibilizers or adhesive base polymers in hot-melt adhesives, especially in combination with SBCs and / or PbP-ngs.

[0064] PbP-g-VAMs according to the application are characterized by a weight average molecular weight of the PbP-backbone of less than 10,000 g / mol, preferably less than 9,000 g / mol, particularly preferably less than 7,000 g / mol, a styrene content of from 1 to 50% by weight, preferably from 3 to 30% by weight, particularly preferably from 5 to 20% by weight, a melting enthalpy of less than 50 J / g, preferably less than 30 J / g, more preferably from 0 to 5 J / g, particularly preferably 0 J / g.

[0065] The PbP-g-UVMH according to the present application is characterized by a weight average molecular weight of the PbP-backbone of less than 10,000 g / mol, preferably less than 9,000 g / mol, particularly preferably less than 7,000 g / mol, a carboxylic anhydride content of 0.1 to 20 wt.-%, preferably of 0.5 to 15 wt.-%, particularly preferably of 1 to 10 wt.-%, a melting enthalpy of less than 50 J / g, preferably of less than 30 J / g, more preferably of 0 to 5 J / g, particularly preferably of 0 J / g.

[0066] In a preferred embodiment, the PbP-g-VAM or PbP-g-UVMH according to the present application is characterized by a weight average molecular weight of less than 20,000 g / mol, preferably less than 15,000 g / mol, particularly preferably less than 10,000 g / mol.

[0067] In an alternative embodiment, the thermoplastic molding material comprises a styrene block copolymer (SBC) and one or more PbPs selected from the group consisting of PbP-ng having a weight average molecular weight Mw of less than 10,000 g / mol, PbP-g-VAM having a weight average molecular weight Mw of less than 20,000 g / mol and PbP-g-UVMH having a weight average molecular weight Mw of less than 20,000 g / mol. w PbP-ng having a weight average molecular weight Mw of less than 10,000 g / mol, PbP-g-VAM having a weight average molecular weight Mw of less than 20,000 g / mol and PbP-g-UVMH having a weight average molecular weight Mw of less than 20,000 g / mol, wherein the SBC comprises a styrene content of 5 to 40 wt.-%, preferably of 10 to 35 wt.-%, particularly preferably of 20 to 35 wt.-%, based on the total mass of the SBC.

[0068] In a preferred embodiment, the sprayability and the improved mechanical properties of the thermoplastic molding material are achieved by the PbP, which comprises at least one PbP-ng having a pour point of less than 50 °C, preferably of less than 30 °C, more preferably of less than 25 °C, determined according to ASTM D97, or at least one PbP-g-VAM or PbP-g-UVMH having a pour point of less than 85 °C, preferably of less than 60 °C, more preferably of less than 55 °C, determined according to ASTM D97.

[0069] In another preferred embodiment, the PbP has a melt viscosity at 170 °C of 1 to 1,000 mPas, preferably of 1 to 500 mPas, particularly preferably of 1 to 300 mPas, measured according to DIN 53019, which further contributes to the sprayability of the thermoplastic molding material.

[0070] In a preferred embodiment of the present application, the thermoplastic molding material comprises in different weight proportions both one or more PbP-ng and (i) one or more PbP-g-VAM, preferably one or more PbP-g-ST or (ii) one or more PbP-g-UVMH, preferably one or more PbP-g-MA. Such an embodiment facilitates better miscibility of the polymer components and thus improves the mechanical properties. Surprisingly, the combination of PbP-ng with (i) PbP-g-VAM or (ii) PbP-g-UVMH results in a lower viscosity of the thermoplastic molding material compared to a thermoplastic molding material comprising only PbP-ng, although PbP-g-VAM, preferably PbP-g-ST or PbP-g-UVMH, preferably PbP-g-MA, has a higher viscosity than PbP-ng by itself. A further technical feature of this embodiment is a reduced migration of the components.

[0071] The PbP-g-VAM or PbP-UVMH polymer can have the same or a different polymer backbone than the PbP-ng. Preferably, the PbP- backbone of the PbP-g-VAM or PbP-g-UVMH polymer is the same as the PbP-ng.

[0072] In a preferred embodiment, the thermoplastic molding material consists of SBCs and PbPs, which can be PbP-ng and / or PbP-g-VAM or PbP-g-UVMH derived from the same or another PbP- backbone. Preferably, the PbP-g-VAM or PbP-g-UVMH is derived from the same PbP- backbone as the PbP-ng.

[0073] In a preferred embodiment, the PbP- backbone is propylene and another selected from the group consisting of ethylene and C4-C 18 copolymer of monomers of an alpha-olefin.

[0074] In addition to the PbP having a Mw of less than 10,000 g / mol, w The thermoplastic molding material according to the present application can comprise further polyolefin-based copolymers than the PbP.

[0075] In a preferred embodiment, the PbP has a glass transition temperature Tg determined by DSC according to DIN EN ISO 11357-2 of less than -20 °C, preferably less than -30 °C and particularly preferably less than -40 °C. g

[0076] In a preferred embodiment, the PbP- backbone is produced by metallocene catalysis.

[0077] ​PbP is preferably a random copolymer of propylene with a propylene proportion of less than 90% by weight, preferably a propylene proportion of 60 to 85% by weight.

[0078] PbP is preferably a copolymer of propylene and ethylene, wherein the copolymer is derived from 60-85 wt% propylene and 15-40 wt% ethylene.

[0079] The SBC may comprise one or more SBCs according to the present invention.

[0080] The SBC preferably has a weight average molecular weight M greater than 30,000 g / mol, preferably greater than 40,000 g / mol, particularly preferably greater than 50,000 g / mol. w .

[0081] In a preferred embodiment, the SBC has a melt flow rate MFR (230° C. / 2.16 kg) determined according to ASTM 1238 of 5 to 250 g / 10 min, preferably 10 to 150 g / 10 min, particularly preferably 20 to 80 g / 10 min.

[0082] In a preferred embodiment, the SBC has a melting enthalpy below 10 J / g, preferably below 5 J / g and thus has an amorphous structure, resulting in a rubber-like behavior that affects the mechanical properties of the thermoplastic material.

[0083] The thermoplastic molding material preferably comprises 10 to 55% by weight, more preferably 20 to 45% by weight, particularly preferably 25 to 40% by weight, of SBC, based on the total mass of the thermoplastic molding material.

[0084] The thermoplastic molding material preferably contains 10-80% by weight of PbP, particularly preferably 20-75% by weight, and more particularly preferably 35-70% by weight of PbP, based on the total mass of the thermoplastic molding material. At these weight ratios, the properties of the individual components of the respective molding material are optimally combined.

[0085] The SBC is preferably selectively hydrogenated at the double bonds in the polymer chain and is characterized by an iodine value of less than 100 g I2 / 100 g polymer, particularly preferably less than 50 g I2 / 100 g polymer.

[0086] The SBC is preferably selected from ABA type elastomeric triblock copolymers, where A consists of rigid styrene units and B consists of elastomeric units, which influence the miscibility of the components. In addition to ABA type elastomeric triblock copolymers, the SBC may also contain AB type elastomeric diblock copolymers or [AB] n Type elastomeric multi-block copolymer, where n is the number of blocks.

[0087] The SBCs are particularly preferably composed of one or more SBCs selected from the group consisting of SEBS, SEPS and SEP polymers.

[0088] In a preferred embodiment, the thermoplastic molding material has a melt viscosity of 100 to 30,000 mPas, preferably 500 to 20,000 mPas, particularly preferably 1,000 to 15,000 mPas, measured at 170°C according to DIN 53019. Within these viscosity ranges, the best spraying results can be achieved using the spraying method suitable for the application.

[0089] In a preferred embodiment, the thermoplastic molding material has an elongation at break of more than 800%, preferably more than 1,000%, measured according to ISO 527, except that the test specimen used (see Figure 1 ) has the following dimensions deviating from the specifications according to ISO 527: total length: 50 mm, narrow part width: 3.3 mm, end part width: 7 mm, narrow parallel part length: 25 mm, thickness: 1 mm.

[0090] The elongation at break is a measure of the deformation behavior of a polymer and is determined according to ISO 527 by a tensile elongation test in the same test run as the determination of the tensile strength. The elongation at break value indicates the percentage elongation of the test specimen at the time of material failure.

[0091] The tensile strength is determined according to ISO 527 by a tensile elongation test, except that the dumbbell-shaped test specimen used (see Figure 1 ) has the following dimensions deviating from the specifications according to ISO 527: total length: 50 mm, narrow part width: 3.3 mm, end part width: 7 mm, narrow parallel part length: 25 mm, thickness: 1 mm. This determines the force per unit area (reported in MPa) required to elongate the specimen.

[0092] In a further preferred embodiment, the thermoplastic molding material has a resilience of more than 70%, preferably more than 80%, particularly preferably more than 90%, wherein the resilience is determined by the method described in the “Measuring methods” section of the present specification. The resilience is a measure of the restorative force of the thermoplastic molding material.

[0093] In a further preferred embodiment, the thermoplastic molding material has a true strain at break of higher than 2.2 at 23°C and a strain hardening exponent of higher than 25 at 23°C.

[0094] The true strain at break, the strain hardening exponent and the yield stress are determined according to the “Tensile test method” described in the “Measuring methods” section of the present specification.

[0095] Low yield stress and high strain hardening exponent are beneficial for stabilizing the network structure upon swelling, since the size and shape of the adhering particles change due to adsorbed water or humidity.

[0096] The strain hardening exponent is a measure of the difference between the initial yield stress and the maximum yield stress. Values greater than 25 lead to a better stress distribution within the network, avoiding high local stresses. This significantly increases the swellability of the network structure.

[0097] An increase in the true strain at break is generally beneficial to allow the network structure to swell.

[0098] The rheological properties of the thermoplastic molding material emphasize the ability to have a reasonable melt strength at the temperature in order to create a durable bond when applied via spray application and are described by tan d@100°C and storage modulus G’@100°C.

[0099] In a further preferred embodiment, the density of the PbP, determined according to ISO 1183, is less than 0.95 g / cm 3 , preferably less than 0.92 g / cm 3 and particularly preferably less than 0.90 g / cm 3 .

[0100] In a further preferred embodiment, the polydispersity index of the PbP is less than 5, preferably less than 3, particularly preferably less than 2.5. The polydispersity index PDI is calculated from the quotient of the weight average molecular weight M w and the number average molecular weight M n and is determined according to the standard ISO 16014.

[0101] The PbP used for the thermoplastic molding material according to the application can either assume the function of the base polymer or replace the function of the plasticizer and tackifier in the formulation. This brings further benefits to the user. For example, fewer ingredients need to be melted and mixed, resulting in a faster, more cost-effective workflow.

[0102] In a preferred embodiment, the thermoplastic molding material is free of tackifiers, which in the sense of the present application means that the content of tackifiers in the thermoplastic material is less than 0.1 wt.-%.

[0103] In a further preferred embodiment, the thermoplastic molding material is free of plasticizers, such as mineral oil, naphthenic oil, paraffinic oil, e.g. naphthenic oil, phthalates, adipates, which in the sense of the present application means that the content of plasticizers in the thermoplastic material is less than 0.1 wt.-%.

[0104] The thermoplastic molding material produced without the addition of tackifiers or plasticizers is particularly environmentally friendly and free of toxicological problems and is therefore suitable for use on the human body.

[0105] In an alternative embodiment, the thermoplastic molding material preferably comprises a tackifier which positively influences the adhesion to the substrate.

[0106] The thermoplastic molding material preferably comprises one or more organic or inorganic pigments, fillers, flame retardants, stabilizers, antistatic agents, antioxidants and light stabilizers.

[0107] Preferably, the antioxidant is selected from sterically hindered phenols and hindered amine light stabilizers (HALS) which inhibit the thermoplastic molding material from developing an odor. It is particularly preferred that the antioxidant is a hindered amine light stabilizer (HALS).

[0108] Furthermore, the present application relates to a process for producing a thermoplastic molding material according to the present application by mixing at least one SBC with at least one PbP, characterized in that

[0109] (a) at least one SBC having a styrene content of 5 to 40 wt.-%, preferably 10 to 35 wt.-%, particularly preferably 20 to 35 wt.-%; and

[0110] (b) one or more PbPs having a weight average molecular weight M w of less than 10,000 g / mol, preferably less than 9,000 g / mol, particularly preferably less than 7,000 g / mol,

[0111] optionally grafted with 1 to 50 wt.-%, preferably 3 to 30 wt.-%, particularly preferably 5 to 20 wt.-% of a vinyl aromatic monomer (PbP-g-VAM), preferably styrene and derivatives thereof (PbP-g-ST),

[0112] or grafted with 0.5 to 20 wt.-%, preferably with 1 to 15 wt.-%, particularly preferably 3 to 10 wt.-% of an unsaturated vinyl monomer comprising a heteroatom (PbP-g-UVMH), preferably a carboxylic anhydride, particularly preferably maleic anhydride (PbP-g-MA),

[0113] wherein the melting enthalpy of the PbP measured according to ISO 11357-2 is less than 50 J / g, preferably less than 30 J / g, particularly preferably 0 to 5 J / g, most particularly preferably 0 J / g.

[0114] The process according to the present application preferably comprises mixing at least one SBC with at least one PbP, particularly using a co-rotating twin-screw extruder at a processing temperature of 200 to 250 °C.

[0115] The present application further relates to a hot-melt adhesive which consists of or comprises, in addition to other components, the thermoplastic molding material according to the present application.

[0116] The invention further relates to the use of the thermoplastic molding material according to the invention or the hotmelt adhesive according to the invention for bonding flexible and / or rigid substrates of any kind.

[0117] The hot melt adhesive or thermoplastic molding material according to the invention is suitable for bonding flexible and / or rigid substrates of any kind, such as paper, cardboard packaging, glass, wood, polypropylene plastic (PP), polyethylene plastic (PE), acrylonitrile-butadiene-styrene copolymer plastic (ABS), in particular for structured substrates or textile substrates, such as fiber webs, woven or non-woven textiles. A person skilled in the art understands a structured substrate to mean a substrate having a profile depth P greater than 1 mm. t substrate.

[0118] Hot-melt adhesive according to the present invention or thermoplastic molding material according to the present invention are particularly preferably used for bonding and fixing coarse-grained bulk solids, for example particles. For these applications, improved thermoplastic molding material or hot-melt adhesive can be applied so that they form a mesh-like breathable and moisture-permeable structure, rather than forming a dense homogeneous film. These mesh-like breathable and moisture-permeable structures (mesh-like structures) are particularly useful for, for example, fixing absorbent to any type of base material. By fixing of this type, filler, desiccant or moisture absorbent can particularly be fixed on, for example, sanitary products, packaging materials, auto parts, vehicle body, furniture, soft furniture or mattress and on any type of surface. In this case, mesh-like structure has fixed above-mentioned particles, and due to specific mechanical properties, maintains certain mechanical load by the motion and expansion depending on liquid content.

[0119] Very surprisingly, thermoplastic molding materials having the characteristics described combine good processing properties of the molding materials due to their low melt viscosity with excellent mechanical properties. This combination of properties enables the molding materials according to the invention to be used as high-performance hotmelt adhesives.

[0120] Measurement method:

[0121] The listed polyolefins are characterized according to the listed standards. Non-standard characterization is performed according to the specification.

[0122] Weight average molecular weight M w

[0123] The weight average molecular weight M of PbP w The determination is carried out in 1,2-o-dichlorobenzene using PP calibration. The measurement is carried out by gel permeation chromatography at a temperature of 135°C. The determination is carried out in accordance with ISO 16014-1.

[0124] The weight average molecular weight M of SBC wThe determination was carried out in THF as mobile phase at a flow rate of 1 mL / min, polystyrene calibration, standard range 680-1,670,000 g / mol. The measurement was carried out by gel permeation chromatography on a column of styrene-divinylbenzene copolymer from PSS at a constant temperature of 40°C. For the measurement, a solution of the SBC polymer was prepared at a concentration of (2 mg polymer) / (ml THF) and 50 μL of the solution were injected. Detection was carried out using a differential refractometer.

[0125] Pour point

[0126] The pour point was determined according to standard ASTM D97.

[0127] Iodine value

[0128] The iodine value was determined according to standard DIN 6162:2014.

[0129] Melt viscosity

[0130] The determination of the melt viscosity was carried out according to standard DIN 53019.

[0131] Polydispersity index PDI

[0132] The polydispersity index PDI was calculated from the quotient of the weight average molecular weight Mw and the number average molecular weight Mn and determined according to standard ISO 16014-1. w The number average molecular weight Mn was determined by means of gel permeation chromatography according to standard ISO 16014-1. n

[0133] Tensile strength

[0134] The tensile strength and the elongation at break of the thermoplastic molding material were determined according to ISO 527, but in this case non-standard test specimens which were produced by hot-melt pressing and which differed in size from the standard test specimens were used. The test specimens used for the measurement of the strength and the elongation at break had the following dimensions: total length: 50 mm, narrow width: 3.3 mm, end width: 7 mm, narrow parallel length: 25 mm, thickness: 1 mm.

[0135] Rebound resilience

[0136] The rebound resilience of the thermoplastic molding material was tested on a tensile / elongation machine from Zwick with the above-mentioned test specimens by stretching a test specimen of the sample to be determined having a starting length L1 to a length L2 of 300% elongation at an elongation rate of 50 mm / min. Subsequently, the test specimen was allowed to relax completely, i.e. the test specimen no longer changed its length under a force of 0 Pa. The resulting length corresponds to L3.

[0137] The rebound resilience R in % is given as follows: R = ((L2 - L3) / L2 - L1) * 100

[0138] ​The oscillatory rheological test method is used to measure the storage modulus and loss factor of the polymer composition. A controlled strain rotational rheometer (e.g., Discovery HR-3, TA Instruments, New Castle, DE, USA, or equivalent) capable of controlling the sample temperature (using a combination of a Peltier cooler and a resistive heater) over a range of at least -0°C to 150°C with an accuracy equal to or better than 0.5°C is used. The rheometer is operated in a parallel plate configuration with a 20 mm stainless steel parallel plate tool.

[0139] The method initially uses a parallel plate gap of 1,000 μm. To compensate for thermal expansion of the tool, the gap is set to 1,000 μm, and a temperature mapping of the actual plate gap (measured using a suitable standard test fluid) is performed over the range of -10°C to 150°C. This mapping is then used throughout the determination of the storage modulus and loss factor parameters.

[0140] The rheometer was heated to 150°C, the polymer composition was introduced into the rheometer, the gap was set to 1,050 μm, the excess protruding sample was trimmed, and then the gap was set to 1,000 μm. (In addition to the compensation of the above-mentioned tools, the axial force control of the rheometer was set to 0 N and maintained within the range of ±0.1 N of force during the experiment, thereby compensating for the thermal expansion / contraction of the sample itself by adjusting the gap to avoid overfilling or underfilling.) The rheometer was then cooled to 130°C, at which point the measurement was started, with a temperature ramp from 130°C to -10°C, and a constant cooling rate of 2°C / minute. The applied strain amplitude was 0.1% and the oscillation frequency was 1 Hz (i.e., one cycle per second). The resulting oscillatory stress was recorded.

[0141] After this step, the sample temperature was set to 23° C. (the temperature was increased to this set point at a rate of 10° C. / min) and the sample was allowed to rest for 4.0 hours at 23° C. At the end of this period, the temperature was set to 10° C. (the temperature was increased to this set point at a rate of 10° C. / min), the sample was equilibrated at −10° C. for 300 seconds, and then a second oscillatory rheological measurement was performed (0.1% strain, 1 Hz oscillation frequency) while the temperature was increased to 130° C. at a constant rate of 2° C. / min.

[0142] Starting from the first decreasing temperature scan, calculate and record the storage modulus G' at 100°C. These values ​​are in Pascals (Pa), accurate to 1 Pa, and reported as "Storage Modulus at 100°C." Starting from the first decreasing temperature scan, calculate and record the loss factor (also known as tan δ) at 100°C. Calculate this dimensionless value to the nearest hundredth and report it as "Loss Factor at 100°C."

[0143] Tensile test method

[0144] The tensile test method is used to determine the yield stress parameter, the maximum stress parameter, the true strain at break parameter and the strain hardening index of a polymer composition sample. Thin film samples formed from the polymer composition are analyzed with a rotational rheometer equipped with a special fixture with counter-rotating rollers and the stress associated with the applied tensile strain is measured and recorded.

[0145] Instrument settings

[0146] A rotational rheometer (ARES G2, TA Instruments, New Castle, DE, USA, or equivalent) is equipped with a fixture with counter-rotating cylindrical rollers specifically designed for the detection of film tensile deformation. One example of a suitable fixture is the extensional viscosity fixture, or EVF (EVF, TA Instruments, or equivalent). The rheometer is also equipped with a forced convection oven FCO (FCO, TA Instruments, or equivalent) and a cooling system (ACS 2, TA Instruments, or equivalent) enabling temperature control with a tolerance of 0.5 °C at least between -50 and 250 °C.

[0147] Sample preparation

[0148] Approximately 10 g of the polymer composition is placed in a polytetrafluoroethylene (PTFE) bowl and introduced into a vacuum oven. After 15 minutes at 170 °C under ambient pressure, the pressure is reduced to 10 mbar and the polymer composition is then kept at 170 °C and 10 mbar for 45 minutes to remove air bubbles from the polymer composition. The polymer composition is removed from the vacuum oven and cooled to ambient laboratory conditions (23 ± 2 °C) for 90 ± 30 minutes, at which point the polymer composition is removed from the PTFE bowl and placed between 2 siliconized papers. A metal shim with a thickness of 0.50 mm is used as a spacer in a hot press, and a film thickness of 0.50 mm is obtained when the polymer film is pressed with the hot press at 90 °C and 10 Bar (instrument settings) for 60 seconds. If 90 °C is not sufficient to melt the polymer composition, a higher temperature is used (but the minimum temperature sufficient to melt the composition). The film is stored in the laboratory at 23 ± 2 °C for at least 120 hours before testing. From the film, individual samples for measurement are punched out with a sample cutter to a sample size of 20.0 mm x 10.0 mm x 0.50 mm. The sample is cut lengthwise with scissors to a final width of 5 ± 0.5 mm. The exact width and thickness are determined using a digital caliper (electronic caliper PRO-MAX Fowler) to the nearest 0.01 mm and entered into the rheometer software.

[0149] Measurement

[0150] The cylinders of the EVF were heated to 80°C for 90±30 seconds in the forced convection oven of the rheometer. A small droplet (0.03±0.01 g) of the polymer composition was then applied to each cylinder. The polymer composition used should exhibit high stiffness (G' greater than 10 MPa at 23°C) so as not to interfere with the measurement. The polymer composition sample was quickly pressed into the molten polymer composition on the EVF cylinder to fix it to the cylinder surface. The sample was placed perpendicular to the axis of rotation of the cylinder.

[0151] The sample mounted on the EVF is then placed in the rheometer's forced convection oven for thermal conditioning and isothermalized at 23 ± 1°C for 300 ± 10 seconds. After this period, the sample is mechanically conditioned. To mechanically condition the sample, the torque transducer is zeroed, the sample is placed under a pre-tension rate of 0.001 s–1 for 0.30 seconds, and then relaxed for 60 seconds. (In this method, all strains are expressed as Hencky strains, also known as "true strains" or "logarithmic strains.")

[0152] Measurements were performed in an FCO oven at 23°C ± 0.5°C. The measured tensile strain rate was 0.01 s⁻¹, with a maximum tensile strain of 4.0. After the measurement, the sample was inspected for cracks. If cracked, the location of the crack was recorded. If the crack was approximately midway between the two cylinders of the EVF, the collected data was considered acceptable. Otherwise, if the polymer film cracked at or near the rotating cylinder, the result was discarded and the measurement was repeated on a duplicate sample.

[0153] analyze

[0154] For tensile stress calculations, a constant volume is assumed. Tensile stress (in megapascals or MPa) and Hencky strain data are calculated based on the raw torque and angular displacement data recorded by the rheometer. The data are plotted semi-logarithmically with the Hencky strain on the abscissa (linear scale) and the tensile stress on the ordinate (logarithmic scale). A linear fit with a positive slope and an R2 value of 0.9 or greater is set to a Hencky strain between 0.5 and 1. Otherwise, the maximum tensile stress recorded during the measurement is reported as the yield stress parameter, also in MPa, accurate to the nearest kPa. The value of the fitted line at zero Hencky strain (i.e., the y-intercept) is defined as the yield stress parameter, in MPa, accurate to the nearest kPa. The maximum stress value in the graph is defined as the maximum stress parameter, in MPa, accurate to the nearest kPa. When the specimen ruptures and / or the reported torque value is less than 100 μNm, the Hencky strain is reported as the fracture strain parameter, a dimensionless value, accurate to the nearest 0.1 (or, in the case of no rupture during the measurement, a strain of 4.0). The difference between the maximum stress and the yield stress divided by the yield stress is defined as the strain hardening exponent, a dimensionless value that is accurate to 1. Example

[0155] To produce the molding material according to the invention, PbP is mixed with SBC. The components used as SBC are styrene block copolymers from the manufacturers Kraton Corporation or DZBH New Material.

[0156] The PbP used was from the manufacturer Clariant PPA 330.

[0157] The chemical, physical and mechanical properties of the two components are characterized in detail in Tables 1 and 2, respectively.

[0158] A) PbP

[0159] Table 1

[0160]

[0161] B) PbP-g-ST or PbP-g-MA polymers

[0162] Synthesis example 1:

[0163] 2,500 g of PbP according to Table 1 was heated to 165°C in a glass apparatus equipped with a stirrer, internal thermometer, and distillation bridge under a nitrogen atmosphere. 250 g of freshly distilled styrene or maleic anhydride were added continuously over 3 hours, while 25 g of di-tert-butyl peroxide was added continuously from a dropping funnel. After the addition was complete, the reaction was continued for 1 hour. A vacuum of approximately 20 mbar was then applied to remove volatile components. The resulting light-colored, pasty, liquid polymer exhibited the properties listed in Table 2.

[0164] Table 2

[0165]

[0166] C) SBC components

[0167] Table 3

[0168]

[0169]

[0170] D) Thickener

[0171] To produce the thermoplastic molding material, a resin-based tackifier was partially blended with the two polymers. The following commercially available tackifiers were used:

[0172] a)Regalite 9100 (Eastman)

[0173] b)Sukorez SU400 (Kolon)

[0174] A melt mixture of the components was produced by melt extrusion from the polymers described in Tables 1 and 2, optionally tackifiers and optionally further additives, in particular antioxidants. This was achieved using a co-rotating twin-screw extruder at a speed of 130 rpm and a processing temperature of 230°C.

[0175] The following antioxidants are added to produce thermoplastic molding materials:

[0176] Antioxidant 1: A sterically hindered phenol manufactured by Clariant;

[0177] Antioxidant 2: A hindered amine light stabilizer (HALS) manufactured by Clariant.

[0178] evaluate

[0179] The comparative examples show comparative mixtures that are resin-free mixtures of non-inventive propylene-based polymers with SBCs or mixtures of inventive propylene-based polymers with other polyolefins.

[0180] The following properties of the hot melt adhesive composition thus prepared were determined:

[0181] -170℃ melt viscosity,

[0182] - Elongation at break [%]

[0183] - Rebound resilience [%].

[0184] To ensure the sprayability of thermoplastic molding materials, their melt viscosity at 170° C. should be less than or equal to 30,000 mPas.

[0185] The following scheme is used to classify mechanical properties:

[0186] Table 4

[0187]

[0188]

[0189]

[0190]

[0191] The thermoplastic molding materials according to the invention have at least a (B) classification in two categories.

[0192] Comparative Example (not the present invention) / (amount, weight %)

[0193] Table 8

[0194]

[0195] Compared to the comparative examples, the inventive examples exhibit significantly better critical mechanical property values. For example, the present invention combines low melt viscosity with high elongation at break and high resilience. Formulations with good mechanical properties but not sprayable, like formulations with low melt viscosity but at least one insufficient mechanical property, fail to solve the technical problems of the present invention. Only the inventive examples have sufficiently low melt viscosity, reasonable elongation at break, and sufficient resilience to achieve sprayable web applications.

[0196] Additional properties were further measured as compiled in Tables 9 and 10:

[0197]

[0198]

[0199] Tables 9 and 10 show additional mechanical properties relevant for use as a stable network structure. The key parameters, namely yield stress, true strain at break, and strain hardening exponent, meet all requirements for mechanical stability in spray-coated network applications. This prevents the material from failing immediately under high local stresses, significantly improving the ductility of the network structure.

Claims

1. A thermoplastic molding material comprising 10 to 55 wt. %, based on the total mass of the thermoplastic molding material, of one or more styrene block copolymers (SBC) and 10 to 80 wt. %, based on the total mass of the thermoplastic molding material, of one or more propylene-based polymers (PbP), wherein: (a) one or more styrene block copolymers (SBC) having a styrene content of 5 to 40 wt. %, based on the total mass of the SBC, and (b) one or more propylene-based polymers (PbP), the weight average molecular weight M of the main chain (PbP-main chain) of the propylene-based polymer w Less than 7,000 g / mol, where the PbP-backbone refers to linear PbP produced using Ziegler or metallocene catalysts, with no substitution at the grafting sites, wherein the PbP has a melting enthalpy of less than 50 J / g measured in accordance with ISO 11357-2 and a glass transition temperature T of less than -20°C determined by DSC in accordance with DIN EN ISO 11357-2 g .

2. The thermoplastic molding material according to claim 1, wherein (a) one or more styrene block copolymers (SBC) have a styrene content of 10 to 35% by weight, based on the total mass of the SBC.

3. The thermoplastic molding material according to claim 1, wherein (a) one or more styrene block copolymers (SBC) have a styrene content of 20 to 35% by weight, based on the total mass of the SBC. 4 . The thermoplastic molding material according to claim 1 , wherein the PbP has a melting enthalpy measured in accordance with ISO 11357-2 of less than 30 J / g. 5 . The thermoplastic molding material according to claim 1 , wherein PbP has a melting enthalpy of 0 to 5 J / g, measured according to ISO 11357-2. 6 . The thermoplastic molding material according to claim 1 , wherein the PbP has a melting enthalpy of 0 J / g measured according to ISO 11357-2.

7. Thermoplastic molding material according to claim 1, wherein the at least one propylene-based polymer PbP is grafted with 1 to 50% by weight of vinylaromatic monomers, based on the weight of the PbP backbone.

8. The thermoplastic molding material according to claim 1, wherein the at least one propylene-based polymer PbP is grafted with 3 to 30% by weight of vinylaromatic monomers, based on the weight of the PbP backbone.

9. Thermoplastic molding material according to claim 1, wherein the at least one propylene-based polymer PbP is grafted with 5 to 20% by weight of vinylaromatic monomers, based on the weight of the PbP backbone.

10. The thermoplastic molding material according to claim 7, wherein the vinyl aromatic monomer is styrene and its derivatives.

11. The thermoplastic molding material according to claim 1, wherein the at least one propylene-based polymer PbP is grafted with 0.1 to 20% by weight of an unsaturated vinyl monomer including heteroatoms, based on the weight of the PbP backbone.

12. The thermoplastic molding material according to claim 1, wherein the at least one propylene-based polymer PbP is grafted with 0.5 to 15% by weight of an unsaturated vinyl monomer comprising heteroatoms, based on the weight of the PbP backbone.

13. The thermoplastic molding material according to claim 1, wherein the at least one propylene-based polymer PbP is grafted with 1 to 10% by weight of an unsaturated vinyl monomer comprising heteroatoms, based on the weight of the PbP backbone.

14. The thermoplastic molding material according to claim 11, wherein the unsaturated vinyl monomer including a heteroatom is a carboxylic anhydride.

15. The thermoplastic molding material according to claim 11, wherein the unsaturated vinyl monomer including a heteroatom is maleic anhydride.

16. The thermoplastic molding material according to claim 1, wherein the PbP is PbP-ng, and the PbP-ng has a pour point of less than 50°C as measured according to ASTM D97, wherein PbP-ng is ungrafted PbP.

17. The thermoplastic molding material according to claim 1, wherein the PbP is PbP-ng, and the PbP-ng has a pour point of less than 30°C as measured according to ASTM D97, wherein PbP-ng is ungrafted PbP.

18. The thermoplastic molding material according to claim 1, wherein the PbP is PbP-ng, and the PbP-ng has a pour point of less than 25°C as measured according to ASTM D97, wherein PbP-ng is ungrafted PbP.

19. The thermoplastic molding material according to claim 7, wherein the pour point of PbP grafted with (i) the vinyl aromatic monomer as measured according to ASTM D97 is lower than 85°C.

20. The thermoplastic molding material according to claim 11, wherein the pour point of PbP grafted with (ii) an unsaturated vinyl monomer including a heteroatom, measured according to ASTM D97, is lower than 85°C.

21. The thermoplastic molding material according to claim 7, wherein the pour point of PbP grafted with (i) the vinyl aromatic monomer as measured according to ASTM D97 is lower than 60°C.

22. The thermoplastic molding material according to claim 11, wherein the pour point of PbP grafted with (ii) an unsaturated vinyl monomer including a heteroatom, as measured according to ASTM D97, is lower than 60°C.

23. The thermoplastic molding material according to claim 7, wherein the pour point of PbP grafted with (i) the vinyl aromatic monomer as measured according to ASTM D97 is lower than 55°C.

24. The thermoplastic molding material according to claim 11, wherein the pour point of PbP grafted with (ii) an unsaturated vinyl monomer including a heteroatom, as measured according to ASTM D97, is lower than 55°C.

25. The thermoplastic molding material according to claim 1, characterized in that The PbP has a melt viscosity at 170° C. measured in accordance with DIN 53019 of 1 to 1,000 mPas.

26. The thermoplastic molding material according to claim 1, characterized in that The melt viscosity of the PbP at 170° C., measured in accordance with DIN 53019, is from 1 to 500 mPas.

27. The thermoplastic molding material according to claim 1, characterized in that The melt viscosity of the PbP at 170° C., measured in accordance with DIN 53019, is from 1 to 300 mPas.

28. The thermoplastic molding material according to claim 1, comprising one or more PbP-ng and (i) one or more vinyl aromatic monomer grafted propylene-based polymers (PbP-g-VAM) or (ii) one or more heteroatom-containing unsaturated vinyl monomer grafted propylene-based polymers (PbP-g-UVMH), wherein PbP-ng is ungrafted PbP.

29. The thermoplastic molding material according to claim 1, characterized in that The glass transition temperature T of the PbP is determined by DSC according to DIN EN ISO 11357-2. g Below -30℃.

30. The thermoplastic molding material according to claim 1, characterized in that The glass transition temperature T of the PbP is determined by DSC according to DIN EN ISO 11357-2. g Below -40℃.

31. Thermoplastic molding material according to claim 1, wherein the PbP backbone is a random copolymer of propylene produced by metallocene catalysis, with a propylene proportion of less than 90% by weight.

32. Thermoplastic molding material according to claim 1, wherein the PbP backbone is a random copolymer of propylene, produced by metallocene catalysis, with a propylene proportion of 60 to 85% by weight.

33. The thermoplastic molding material according to claim 1, characterized in that The weight average molecular weight M of the SBC w Greater than 30,000 g / mol.

34. The thermoplastic molding material according to claim 1, characterized in that The weight average molecular weight M of the SBC w Greater than 40,000 g / mol.

35. The thermoplastic molding material according to claim 1, characterized in that The weight average molecular weight M of the SBC w Greater than 50,000 g / mol.

36. The thermoplastic molding material according to claim 1, characterized in that The SBC comprises at least one selected from ABA type elastomeric triblock copolymer, AB type elastomeric diblock copolymer and [AB] n An elastomeric block copolymer of the type elastomeric multi-block copolymer, wherein A consists of rigid styrene units, B consists of elastomeric units, and n is the number of blocks.

37. The thermoplastic molding material according to claim 1, characterized in that The melt viscosity of the thermoplastic molding material at 170° C., measured in accordance with DIN 53019, is from 100 to 30,000 mPas.

38. The thermoplastic molding material according to claim 1, characterized in that The melt viscosity of the thermoplastic molding material at 170° C., measured in accordance with DIN 53019, is from 500 to 20,000 mPas.

39. The thermoplastic molding material according to claim 1, characterized in that The melt viscosity of the thermoplastic molding material at 170° C., measured in accordance with DIN 53019, is from 1,000 to 15,000 mPas.

40. The thermoplastic molding material according to claim 1, characterized in that The material has an elongation at break greater than 800%, measured according to ISO 527, except that the specimen has the following dimensions that deviate from the standard: total length: 50 mm, narrow part width: 3.3 mm, end width: 7 mm, narrow parallel part length: 25 mm, thickness: 1 mm.

41. The thermoplastic molding material according to claim 1, characterized in that The material has an elongation at break greater than 1,000%, measured according to ISO 527, except that the specimen has the following dimensions that deviate from the standard: total length: 50 mm, narrow portion width: 3.3 mm, end width: 7 mm, narrow parallel portion length: 25 mm, thickness: 1 mm.

42. The thermoplastic molding material according to claim 1, characterized in that The material has a resilience R greater than 70%, and the resilience R is measured by a resilience test, wherein the specimen is stretched 300% of the initial length L1 to a length L2 at an elongation rate of 50 mm / min on a stretching / elongation machine from Zwick, and then completely relaxed to a relaxed length L3, whereby the resilience R is calculated according to the formula R=((L2–L3) / L2–L1)*100. The dimensions of the specimen are as follows: total length: 50 mm, narrow part width: 3.3 mm, end width: 7 mm, narrow parallel part length: 25 mm, thickness: 1 mm.

43. The thermoplastic molding material according to claim 1, characterized in that The material has a resilience R greater than 80%, and the resilience R is measured by a resilience test, wherein the specimen is stretched 300% of the initial length L1 to a length L2 at an elongation rate of 50 mm / min on a stretching / elongation machine from Zwick, and then completely relaxed to a relaxed length L3, whereby the resilience R is calculated according to the formula R=((L2–L3) / L2–L1)*100. The dimensions of the specimen are as follows: total length: 50 mm, narrow part width: 3.3 mm, end width: 7 mm, narrow parallel part length: 25 mm, thickness: 1 mm.

44. The thermoplastic molding material according to claim 1, characterized in that The material has a resilience R greater than 90%, and the resilience R is measured by a resilience test, wherein the specimen is stretched 300% of the initial length L1 to a length L2 at an elongation rate of 50 mm / min on a stretching / elongation machine from Zwick, and then completely relaxed to a relaxed length L3, whereby the resilience R is calculated according to the formula R=((L2–L3) / L2–L1)*100. The dimensions of the specimen are as follows: total length: 50 mm, narrow part width: 3.3 mm, end width: 7 mm, narrow parallel part length: 25 mm, thickness: 1 mm.

45. The thermoplastic molding material of claim 1, wherein the thermoplastic molding material comprises less than 0.1 wt% of a tackifier.

46. ​​The thermoplastic molding material of claim 1, wherein the material comprises less than 0.1% by weight of plasticizer.

47. The thermoplastic molding material according to claim 1, wherein the thermoplastic molding material further comprises an antioxidant, and the antioxidant is a hindered amine light stabilizer.

48. Process for producing a thermoplastic molding material according to any one of claims 1 to 47 by mixing at least one SBC with at least one PbP.

49. The process for producing a thermoplastic molding material according to claim 48, wherein the at least one SBC comprises a styrene content of 10 to 35% by weight, based on the total mass of the SBC.

50. The process for producing a thermoplastic molding material according to claim 48, wherein the at least one SBC comprises a styrene content of 20 to 35% by weight, based on the total mass of the SBC.

51. The process for producing a thermoplastic molding material according to claim 48, wherein the melting enthalpy of PbP measured in accordance with ISO 11357-2 is less than 30 J / g.

52. The process for producing a thermoplastic molding material according to claim 48, wherein the melting enthalpy of PbP measured in accordance with ISO 11357-2 is from 0 to 5 J / g.

53. The process for producing a thermoplastic molding material according to claim 48, wherein the melting enthalpy of PbP measured in accordance with ISO 11357-2 is 0 J / g.

54. The process for producing a thermoplastic molding material according to claim 48, wherein at least one PbP is grafted with 1 to 50% by weight of a vinyl-aromatic monomer.

55. The process for producing a thermoplastic molding material according to claim 48, wherein at least one PbP is grafted with 3 to 30% by weight of a vinyl-aromatic monomer.

56. The process for producing a thermoplastic molding material according to claim 48, wherein at least one PbP is grafted with 5 to 20% by weight of a vinyl-aromatic monomer.

57. The method for producing a thermoplastic molding material according to claim 54, wherein the vinyl-aromatic monomer is styrene and its derivatives.

58. The process for producing a thermoplastic molding material according to claim 48, wherein at least one PbP is grafted with 0.1 to 20% by weight of an unsaturated vinyl monomer comprising heteroatoms.

59. The process for producing a thermoplastic molding material according to claim 58, wherein at least one PbP is grafted with 0.5 to 15% by weight of an unsaturated vinyl monomer comprising heteroatoms.

60. The process for producing a thermoplastic molding material according to claim 58, wherein at least one PbP is grafted with 1 to 10% by weight of an unsaturated vinyl monomer comprising heteroatoms.

61. The method for producing a thermoplastic molding material according to claim 58, wherein the unsaturated vinyl monomer including a heteroatom is a carboxylic anhydride monomer.

62. The method for producing a thermoplastic molding material according to claim 58, wherein the unsaturated vinyl monomer including a heteroatom is maleic anhydride.

63. The method according to claim 48, wherein The mixing was performed using a co-rotating twin-screw extruder at a processing temperature of 200°C to 250°C.

64. Hot melt adhesive consisting of the thermoplastic molding material according to any one of claims 1 to 47.

65. Use of the thermoplastic molding material according to any one of claims 1 to 47 for bonding substrates.

66. Use of the thermoplastic molding material according to any one of claims 1 to 47 for fixing granular or powdered materials to smooth, structured or textile substrates.

67. Use of the hot melt adhesive according to claim 64 for bonding substrates.

68. Use of the hot melt adhesive according to claim 64 for fixing granular or powdered materials to smooth, structured or textile substrates.

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