Fiber reinforced thermoplastic polymer composition

Abstract

The present invention relates to a pellet comprising a fiber-reinforced thermoplastic polymer composition comprising a thermoplastic polymer and a plurality of composite filaments wherein each composite filament comprises a first filament consisting of an inorganic material and a second filament consisting of an inorganic material, the first filaments have a glass transition temperature greater than or equal to 400 DEG C, the second filaments consist of a metallic material and are in contact with the first filaments, and wherein the weight average length of the composite filaments in the pellet is at least 5.0 mm.

Description

[0001] This invention relates to granules comprising a fiber-reinforced thermoplastic polymer composition and a method for producing such granules. The invention also relates to a molded article made from such granules.

[0002] Fiber-reinforced thermoplastic polymer compositions are widely used, wherein the thermoplastic polymer is reinforced with glass fibers. The glass fibers can be cut before being melt-blended with the thermoplastic polymer to disperse therein. Optionally, the glass fibers can be combined with the thermoplastic polymer to form long glass fibers instead of being chopped short.

[0003] Fiber-reinforced thermoplastic compositions with high electromagnetic / radio frequency interference (EMI / RFI) shielding effectiveness are known through the use of conductive fibers. For example, US4566990 discloses a thermoplastic polymer composition with high electromagnetic interference shielding effectiveness comprising a thermoplastic resin or resin blend, a metal sheet, and metal or metal-coated fibers.

[0004] US20170001336A1 discloses a fiber-reinforced multilayer granule comprising a sheath and a core layer. The sheath comprises a resin composition containing a thermoplastic resin (a1) and a fiber filler (b1), wherein the weight-average fiber length (Lw) of the fiber filler (b1) is 0.1 mm to less than 0.5 mm and the weight-average fiber length / number-average fiber length ratio (Lw / Ln) is 1.0 to less than 1.8. The core layer comprises a resin composition containing a thermoplastic resin (a2) and a fiber filler (b2), wherein the weight-average fiber length (Lw) of the fiber filler (b2) is 0.5 mm to less than 15.0 mm and the weight-average fiber length / number-average fiber length ratio (Lw / Ln) is 1.8 to less than 5.0.

[0005] US2010068518 discloses a molding material comprising: (i) 1-50 wt% of a continuous reinforcing fiber bundle (A); (ii) 0.1-10 wt% of a polyarylene sulfide prepolymer (B) comprising at least 50 wt% of a cyclic polyarylene sulfide and having a weight-average molecular weight of less than 10,000, or a polyarylene sulfide (B') having a weight-average molecular weight of 10,000 or greater and having a dispersion of 2.5 or less expressed in terms of weight-average molecular weight / number-average molecular weight; and (iii) 40-98.9 wt% of a thermoplastic resin (C), wherein component (C) adheres to a composite of component (A) and component (B) or (B').

[0006] US5935508A discloses a method for manufacturing a fiber-reinforced intermediate suitable for thermoplastic processing, comprising impregnating a continuous fiber with a resin composition comprising at least one radiation-polymerizable component; exposing the impregnated fiber to radiation to achieve polymerization of such component; and cutting the product to form a thermoplastic-processable intermediate.

[0007] One object of the present invention is to provide a granule that can be used to prepare molded articles with high EMI shielding performance.

[0008] Therefore, the present invention provides a pellet comprising a fiber-reinforced thermoplastic polymer composition containing a thermoplastic polymer and a plurality of co-filaments.

[0009] Each composite filament comprises a first filament and a second filament. The first filament is composed of an inorganic material and has a glass transition temperature greater than or equal to 400°C. The second filament is composed of a metallic material and is in contact with the first filament.

[0010] The weight-average length of the composite fibers in the granules is at least 5.0 mm.

[0011] The pellets comprise, or consist of, a fiber-reinforced thermoplastic polymer composition.

[0012] The composite filaments used in this invention have high shielding performance against electromagnetic waves. The inventors have recognized that the relatively large average length of the composite filaments in the granules according to the invention allows the composite filaments to be close together to form a network for improved EMI shielding performance in molded articles made from the granules according to the invention.

[0013] Composite filaments can exist as bundled composite filaments in the granules according to the invention, or they can be dispersed in the granules. Typically, granules containing bundled composite filaments can be obtained by a so-called wire coating process, and granules containing dispersed composite filaments can be obtained by a so-called pultrusion process, as explained in detail herein.

[0014] The filaments in the granules can be composed of composite filaments. Optionally, the filaments in the granules may further include glass filaments. The presence of glass filaments can be beneficial in terms of production cost and / or mechanical properties of molded articles made from the granules.

[0015] The weight ratio between composite fibers and glass fibers in the granules can be any ratio, such as 10:90-90:10, 10:90-50:50, or 50:50-90:10. This weight ratio can be selected based on the desired EMI shielding performance, as well as cost and mechanical properties.

[0016] Sheathed continuous multifiber strand

[0017] In one aspect, the invention provides a pellet comprising a continuous multifilament strand with a sheath, the strand comprising a longitudinally extending core and a polymer sheath tightly surrounding the core.

[0018] The core comprises impregnated continuous bicomponent multifiber strands, each impregnated continuous bicomponent multifiber strand containing at least one continuous bicomponent multifiber strand with bundled composite filaments, and

[0019] The polymer sheath is composed of a thermoplastic polymer composition containing the thermoplastic polymer.

[0020] Preferably, the pellets consist of continuous multi-fiber strands with sheaths.

[0021] Such core-sheath structures of continuous multifilament strands with sheaths are known in themselves and are described in detail, for example, in WO2009 / 080281, which is incorporated herein by reference.

[0022] The present invention also provides a method for preparing granules according to the present invention, comprising the following sequential steps:

[0023] a) Unwind from at least one continuous bicomponent multifilament package.

[0024] b) Applying an impregnating agent to the at least one continuous bicomponent multifiber strand to form an impregnated continuous bicomponent multifiber strand.

[0025] c) Applying a sheath of the thermoplastic polymer composition around an impregnated continuous multifiber strand to form a sheathed continuous multifiber strand, and

[0026] d) Cut the sheathed continuous multifiber strands into granules.

[0027] Preferably, the weight-average length of the composite fibers in the granules is substantially the same as the length of the granules, and is preferably 10-55 mm, more preferably 10-40 mm, more preferably 10-30 mm, and most preferably 10-20 mm.

[0028] The core may comprise an impregnated continuous bicomponent multifiber strand containing at least one continuous bicomponent multifiber strand and an impregnated continuous glass multifiber strand containing at least one continuous glass multifiber strand.

[0029] When the filaments in the granules also contain glass filaments, the granules can be prepared by a method including the following steps:

[0030] a) Unwinding from at least one continuous bicomponent multifiber strand package

[0031] a2) Unwinding from at least one continuous glass multifiber strand from a roll.

[0032] b) Applying an impregnating agent to the at least one continuous bicomponent multifiber strand to form an impregnated continuous bicomponent multifiber strand.

[0033] b2) Applying an impregnating agent to the at least one continuous glass multifiber strand to form an impregnated continuous glass multifiber strand.

[0034] c') Applying a thermoplastic polymer sheath around impregnated continuous bicomponent multifiber strands and impregnated continuous glass multifiber strands to form sheathed continuous multifiber strands, and

[0035] d) Cut the strands into granules.

[0036] The order of the steps to be performed is a) and a2), then b and b2), then c'), and then d).

[0037] Steps a) and a2) can be performed in any order.

[0038] Steps b) and b2) can be performed as separate steps, but are preferably performed as a step in which an impregnating agent is applied to the at least one continuous bicomponent multifiber strand and the at least one continuous glass multifiber strand to form impregnated continuous bicomponent multifiber strand and impregnated continuous glass multifiber strand.

[0039] Compositions containing dispersed composite filaments

[0040] In one aspect, the present invention provides a pellet in which a plurality of composite filaments are dispersed in a matrix of a thermoplastic polymer.

[0041] Suitable examples of thermoplastic polymers with granular matrices are those described herein as examples of thermoplastic polymers in thermoplastic polymer compositions that serve as sheaths of continuous multi-filament polymer strands.

[0042] The pellets may further contain additives. Suitable examples of additives are those described herein as examples of additives in thermoplastic polymer compositions serving as sheaths of continuous multi-filament polymer strands.

[0043] Such granules can be obtained, for example, by the pultrusion process described in US 291064B1, which is incorporated herein by reference.

[0044] The present invention also provides a method for preparing granules according to the present invention, comprising the following sequential steps:

[0045] i) Unwinding from at least one continuous bicomponent multifiber strand package.

[0046] ii) Spread at least one continuous bicomponent multifilament strand into a single composite filament.

[0047] iii) Drawing composite filaments through a melt of a thermoplastic polymer matrix containing a thermoplastic polymer, thereby impregnating the composite filaments with the thermoplastic polymer to obtain strands in which the composite filaments are dispersed in a thermoplastic polymer matrix, and

[0048] iv) Cut the strands to obtain pellets.

[0049] Preferably, the weight-average length of the filaments in the granules is substantially the same as the length of the granules, and is preferably 5.0-10 mm, more preferably 5.0-8.0 mm.

[0050] When the filaments in the granules further comprise glass filaments, the granules can be prepared by a method including the following steps:

[0051] i) Unwinding from at least one continuous bicomponent multifiber strand package.

[0052] i2) Unwinding from at least one continuous glass multifiber strand from a roll.

[0053] ii) Spread at least one continuous bicomponent multifilament strand into a single composite filament.

[0054] ii2) Spread at least one continuous glass multifiber strand into a single glass filament.

[0055] iii') Drawing composite filaments and glass filaments through a melt of a thermoplastic polymer composition containing a thermoplastic polymer to impregnate the composite filaments and glass filaments with the thermoplastic polymer to obtain strands, wherein the composite filaments and glass filaments are dispersed in a thermoplastic polymer matrix, and

[0056] iv) Cut the strands to obtain pellets.

[0057] The order of the steps to be performed is i) and i2), then ii and ii2), then iii'), and then d).

[0058] Steps i) and i2) can be performed in any order.

[0059] Steps ii) and ii2) can be performed in any order.

[0060] Molded products

[0061] The molded article according to the invention is manufactured by molding granules comprising the granules according to the invention. The granules used for molding may consist of granules according to the invention. In addition to the invention, the granules used for molding may further comprise other types of granules. For example, said other types of granules may be granules comprising a thermoplastic polymer and glass fibers, or granules comprising a thermoplastic polymer without glass fibers. Suitable examples of such additional polymers are those described herein as examples of thermoplastic polymers in thermoplastic polymer compositions comprising a continuous multi-filament polymer sheath.

[0062] Therefore, the present invention provides a molded article manufactured by molding granules according to the invention and optionally granules comprising a thermoplastic composition comprising a thermoplastic polymer and optionally glass fibers.

[0063] The thermoplastic polymer in the optional granules is preferably the same as that in the granules according to the invention, and is preferably polypropylene.

[0064] Optional granules without glass fibers can be manufactured using conventional methods. Optional granules containing glass fibers are preferably granules produced by wire coating or pultrusion processes.

[0065] In some embodiments, the optional pellets comprise a sheathed continuous multifilament strand comprising a longitudinally extending core and a polymer sheath tightly surrounding the core.

[0066] The core comprises an impregnated continuous glass multifiber strand, the impregnated continuous glass multifiber strand comprising at least one continuous glass multifiber strand, and

[0067] The polymer sheath is composed of a thermoplastic polymer composition containing a thermoplastic polymer.

[0068] In some embodiments, the optional granules comprise glass filaments dispersed in a matrix of thermoplastic polymer.

[0069] Preferably, the optional granules have the same structure as the granules according to the invention, that is, when the granules according to the invention have a sheathed core structure, the optional granules used in combination also have a sheathed core structure, and when the granules according to the invention have a structure in which filaments are dispersed in a matrix, the optional granules used in combination also have such a structure.

[0070] The amount of the granules according to the invention relative to the total granules used in the manufacture of the molded articles is 5-100% by weight, for example 5-50% by weight, or 50-100% by weight.

[0071] Suitable examples of molding methods include injection molding, compression molding, extrusion (optionally followed by thermoforming), and extrusion compression molding.

[0072] In some particularly preferred embodiments, the molded article is an injection-molded article. Preferably, the weight-average length of the composite filaments in the article is at least 1.0 mm, more preferably 1.0-2.0 mm, for example 1.3-1.7 mm.

[0073] In some particularly preferred embodiments, the molded article is an extruded molded article. Preferably, the weight-average length of the composite filaments in the article is at least 0.5 mm, more preferably at least 1.0 mm, and more preferably 1.0-2.0 mm, for example 1.3-1.7 mm. The type of extrusion apparatus has a certain influence on the weight-average length of the composite filaments in the article. Using a single-screw extruder generally yields a longer weight-average length of composite filaments than using a twin-screw extruder.

[0074] Molded products are preferably selected from battery casings, battery trays, battery charging stations, power tools, building and structural shielding boxes, scaffolding, structural frames and flooring.

[0075] Composite fibers

[0076] The composite fibers in the granules of the present invention are described in detail in WO2222156922A1, which is incorporated herein by reference.

[0077] Each composite filament comprises a first filament and a second filament. The first filament is composed of an inorganic material and has a glass transition temperature greater than or equal to 400°C. The second filament is composed of a metallic material and is in contact with the first filament. Preferably, the composite filament consists of a first filament and a second filament.

[0078] "Inorganic materials" should be understood as materials that do not contain plant or animal components or contain them only to a small extent as impurities. Inorganic materials can be natural stones, especially granite, basalt, slate, sandstone, or limestone. Inorganic materials are preferably understood as materials that contain little or no carbon as an impurity. Inorganic materials can be ceramics, glass (crystalline or amorphous glass), especially E-glass, S-glass, or C-glass.

[0079] The "glass transition temperature" of a material (especially glass, polymer, or ceramic) describes the temperature at which the material changes from its solid state to a viscous or liquid state.

[0080] Preferably, the first filament is a glass filament or a basalt filament.

[0081] "Metallic materials" should be understood to refer specifically to substances located to the left and below the dividing line from boron to astatine in the periodic table.

[0082] Particularly preferably, the second filament has an aluminum content of at least 98 wt%, at least 99 wt%, or at least 99.5 wt%, or a copper content of at least 98 wt%, at least 99 wt%, or at least 99.5 wt%.

[0083] "Composite filament" describes a filament having virtually unlimited length, consisting of at least two longitudinally extending filaments of different material properties, wherein the two materially different filaments are physically and / or chemically bonded to each other to form a composite filament. Composite filaments can have a length-to-diameter ratio greater than or equal to 1000.

[0084] Preferably, the first filament and the second filament are physically and / or chemically connected to each other to form a composite filament, and the contact area between the first filament and the second filament is at least 5% of the circumference of the first filament.

[0085] Preferably, the contact area between the first filament and the second filament is 5-95% of the circumference of the first filament, more preferably 10-90%, and even more preferably 15-85%.

[0086] Details of continuous multifiber strands with sheaths

[0087] Granules containing sheathed continuous multifiber strands according to the invention have the advantage that their manufacturing method can be carried out at a higher speed than pultrusion and that materials with low MFI can be used.

[0088] The pellets comprise or consist of sheathed continuous multifilament strands. The sheathed continuous multifilament strands comprise or consist of a core and a polymer sheath. The core has a generally cylindrical shape and comprises impregnated continuous bicomponent multifilament strands containing composite filaments. The core is tightly surrounded by a polymer sheath around its periphery, the polymer sheath being generally tubular and composed of a thermoplastic polymer composition. The length of the composite filaments is substantially equal to the axial length of the pellet.

[0089] The core is a material that is essentially free of sheath. The sheath is essentially free of filaments. Such a granular structure can be obtained by, for example, the wire coating method disclosed in WO2009 / 080281, and is different from the granular structure obtained by, for example, the typical pultrusion type method disclosed in US6,291,064.

[0090] Preferably, the polymer sheath is substantially free of composite filaments, which means that it contains less than 2% by weight of filaments based on the total weight of the polymer sheath.

[0091] Preferably, the core radius is 800-4000 micrometers and / or the polymer sheath thickness is 500-1500 micrometers.

[0092] Preferably, the core accounts for 35-60% of the cross-sectional area of ​​the pellets, and the sheath accounts for 40-65% of the cross-sectional area of ​​the pellets.

[0093] In some embodiments, the core occupies 3-35% of the cross-sectional area of ​​the continuous multifiber strands of the sheath, and the sheath occupies 65-97% of the cross-sectional area of ​​the continuous multifiber strands of the sheath. In some embodiments, the core occupies 35-60% of the cross-sectional area of ​​the continuous multifiber strands of the sheath, and the sheath occupies 40-65% of the cross-sectional area of ​​the continuous multifiber strands of the sheath.

[0094] Preferably, the amount of core relative to the sheathed continuous multifiber strand is 10-80% by weight, for example 10-50% by weight (e.g., 25-45% by weight), or 50-80% by weight (e.g., 60-75% by weight). Preferably, the amount of sheath relative to the sheathed continuous multifiber strand is 20-90% by weight, for example 20-50% by weight (e.g., 25-40% by weight), or 50-90% by weight (e.g., 55-75% by weight). Preferably, the total amount of core and sheath relative to the sheathed continuous multifiber strand is 100% by weight.

[0095] Polymer sheath

[0096] The sheath tightly surrounds the core. As used herein, the term "tightly surrounds" should be understood to mean that the polymer sheath is substantially in complete contact with the core. In other words, the sheath is applied to the core in such a manner that there is no intentional gap between the inner surface of the sheath and the core, which contains impregnated continuous multifilament strands. However, those skilled in the art will understand that a small gap may form between the polymer sheath and the core due to process variations.

[0097] The polymer sheath is composed of a thermoplastic polymer composition.

[0098] Thermoplastic polymer composition of polymer sheath

[0099] The thermoplastic polymer composition comprises a thermoplastic polymer. Preferably, the thermoplastic polymer composition consists of a thermoplastic polymer and the additives described below.

[0100] The thermoplastic polymer composition may have a melt flow index of 1.0-150 dg / min, for example at least 1.0 dg / min and less than 20 dg / min, or 20-150 dg / min, as measured according to ISO 1133-1:2011 (2.16 kg / 230 °C).

[0101] Thermoplastic polymer in the thermoplastic polymer composition of polymer sheath

[0102] The amount of thermoplastic polymer relative to the thermoplastic polymer composition may be at least 50% by weight, for example 50-99.9% by weight, 75-99.9% by weight, or 95-99.9% by weight.

[0103] Suitable examples of thermoplastic polymers include, but are not limited to, polyamides, such as polyamide 6, polyamide 66 or polyamide 46; polyolefins, such as polypropylene and polyethylene; polyesters, such as polyethylene terephthalate, polybutylene terephthalate; polycarbonate; polyphenylene sulfide; polyurethane and mixtures thereof.

[0104] The thermoplastic polymer is preferably a polyolefin, more preferably an elastomer selected from the following polyolefins: polypropylene or ethylene and an α-olefin comonomer having 4-8 carbon atoms, and any mixture thereof.

[0105] In one embodiment, the preferred thermoplastic polymer composition comprises at least 80% by weight of a thermoplastic polymer, such as at least 90% by weight, at least 93% by weight, at least 95% by weight, at least 97% by weight, at least 98% by weight, or at least 99% by weight, based on the thermoplastic polymer composition. In a specific embodiment, the thermoplastic polymer composition consists of a thermoplastic polymer. In another embodiment, the thermoplastic polymer composition comprises at least 60% by weight, such as at least 70% by weight, such as at least 75% by weight, and / or at most 99% by weight, such as at most 95% by weight, such as at most 90% by weight, of a thermoplastic polymer.

[0106] Thermoplastic polymers may have a melt flow index of 1.0-150 dg / min, as measured according to ISO 1133-1:2011 (2.16 kg / 230 °C). In some embodiments, the melt flow index of the thermoplastic polymer is at least 1.0 dg / min and less than 20 dg / min, preferably 5.0-19 dg / min, more preferably 6.0-18 dg / min, as measured according to ISO 1133-1:2011 (2.16 kg / 230 °C). In some embodiments, the melt flow index of the thermoplastic polymer is 20-150 dg / min, for example 30-140 dg / min, as measured according to ISO 1133-1:2011 (2.16 kg / 230 °C). Preferably, the melt flow index of the thermoplastic polymer is 50-130 dg / min, measured according to ISO 1133-1:2011 (2.16 kg / 230 °C). This imparts good mechanical properties to the obtained composition.

[0107] Polypropylene can be, for example, a homopolymer of propylene, a random copolymer of propylene, or a multiphase copolymer of propylene.

[0108] Propylene homopolymers can be obtained by polymerizing propylene under suitable polymerization conditions. Propylene copolymers can be obtained by copolymerizing propylene with one or more other α-olefins (preferably ethylene) under suitable polymerization conditions. The preparation of propylene homopolymers and copolymers is described, for example, in Moore, EP (1996) Polypropylene Handbook. Polymerization, Characterization, Properties, Processing, Applications, Hanser Publishers: New York.

[0109] The random propylene copolymer may contain ethylene as a comonomer or an α-olefin selected from α-olefins having 4-10 carbon atoms, preferably ethylene, 1-butene, 1-hexene, or any mixture thereof. The amount of comonomer is preferably up to 10% by weight based on the random propylene copolymer, for example, 2-7% by weight based on the random propylene copolymer.

[0110] Polypropylene can be manufactured using any known polymerization technique and any known polymerization catalyst system. Regarding techniques, references can be given to slurry, solution, or gas-phase polymerization; regarding catalyst systems, references can be given to Ziegler-Natta, metallocene, or single-point catalyst systems. These are all known in the art.

[0111] Multiphase propylene copolymers are typically prepared in one or more reactors by polymerizing propylene in the presence of a catalyst, followed by polymerizing an ethylene-α-olefin mixture. The resulting polymer material is multiphase, but its specific morphology usually depends on the preparation method and the monomer ratios used.

[0112] Multiphase propylene copolymers can be produced using any conventional techniques known to those skilled in the art, such as multi-stage process polymerization, including bulk polymerization, gas-phase polymerization, slurry polymerization, solution polymerization, or any combination thereof. Any conventional catalyst system can be used, such as Ziegler-Natta or metallocene. Such techniques and catalysts are described, for example, in WO06 / 010414; Polypropylene and other Polyolefins, Ser van der Ven, Studies in PolymerScience 7, Elsevier 1990; WO06 / 010414, US4399054, and US4472524.

[0113] Preferably, a Ziegler-Natta catalyst is used to produce the multiphase propylene copolymer.

[0114] Multiphase propylene copolymers can be prepared by methods including the following:

[0115] - In the presence of a catalyst system, propylene and optionally ethylene and / or α-olefins are polymerized to obtain a propylene-based matrix, and

[0116] Subsequently, in the presence of a catalyst system, ethylene and α-olefins are polymerized in a propylene-based matrix to obtain dispersed ethylene-α-olefin copolymers. These steps are preferably carried out in separate reactors. The catalyst systems used for the first and second steps can be different or the same.

[0117] The multiphase propylene copolymer composition comprises a propylene-based matrix and a dispersed ethylene-α-olefin copolymer. The propylene-based matrix typically forms a continuous phase in the multiphase propylene copolymer. The amounts of the propylene-based matrix and the dispersed ethylene-α-olefin copolymer can be determined using methods known in the art. 13 Measured by C-NMR.

[0118] The propylene-based matrix consists of propylene homopolymers and / or propylene copolymers, the propylene copolymers being composed of at least 70% by weight of propylene monomer units and at most 30% by weight of comonomer units selected from ethylene monomer units and α-olefin monomer units having 4-10 carbon atoms, for example, a composition of at least 80% by weight of propylene monomer units and at most 20% by weight of comonomer units, at least 90% by weight of propylene monomer units and at most 10% by weight of comonomer units, or at least 95% by weight of propylene monomer units and at most 5% by weight of comonomer units, based on the total weight of the propylene-based matrix.

[0119] Preferably, the comonomers in the propylene copolymer based on a propylene matrix are selected from ethylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, and 1-octene, with ethylene being the most preferred.

[0120] Preferably, the propylene-based matrix is ​​composed of propylene homopolymer.

[0121] Based on the melt flow index (MFI) of the propylene matrix (before incorporating the multiphase propylene copolymer into the composition), MFI PP This can be, for example, at least 0.1 dg / min, at least 0.2 dg / min, at least 0.3 dg / min, at least 0.5 dg / min, at least 1 dg / min, at least 1.5 dg / min, and / or, for example, at most 50 dg / min, at most 40 dg / min, at most 30 dg / min, at most 25 dg / min, at most 20 dg / min, measured according to ISO 1133 (2.16 kg / 230 °C). MFI PPIt can be, for example, 0.1-50 dg / min, for example, 0.2-40 dg / min, for example, 0.3-30 dg / min, for example, 0.5-25 dg / min, for example, 1-20 dg / min, for example, 1.5-10 dg / min, measured according to ISO 1133 (2.16 kg / 230 °C).

[0122] The presence of the propylene-based matrix can be, for example, 50-95% by weight. Preferably, the presence of the propylene-based matrix is ​​60-85% by weight, for example at least 65% by weight, or at least 70% by weight, and / or at most 78% by weight, based on the total amount of the multiphase propylene copolymer.

[0123] The propylene-based matrix is ​​preferably semi-crystalline, meaning it is neither 100% amorphous nor 100% crystalline. For example, the propylene-based matrix is ​​at least 40% crystalline, such as at least 50%, such as at least 60% crystalline, and / or, for example, at most 80% crystalline, such as at most 70% crystalline. For example, the propylene-based matrix has a crystallinity of 60-70%. For the purposes of this invention, the crystallinity of the propylene-based matrix is ​​measured using differential scanning calorimetry (DSC) according to ISO 11357-1 and ISO 11357-3 (1997), with a scan rate of 10 °C / min, a sample of 5 mg, and a second heating curve using 207.1 J / g as the theoretical standard for 100% crystalline material.

[0124] In addition to the propylene-based matrix, multiphase propylene copolymers also contain dispersed ethylene-α-olefin copolymers. These dispersed ethylene-α-olefin copolymers are also referred to herein as the "dispersed phase." The dispersed phase is embedded in the multiphase propylene copolymer in a discontinuous form. The particle size of the dispersed phase is typically 0.05–2.0 micrometers and can be determined by transmission electron microscopy (TEM). The amount of dispersed ethylene-α-olefin copolymer in the multiphase propylene copolymer may sometimes be referred to herein as RC.

[0125] The amount of ethylene monomer units in an ethylene-α-olefin copolymer can be, for example, 20-65% by weight. The amount of ethylene monomer units in a dispersed ethylene-α-olefin copolymer in a multiphase propylene copolymer may sometimes be referred to herein as RCC2.

[0126] The α-olefin in the ethylene-α-olefin copolymer is preferably selected from α-olefins having 3-8 carbon atoms. Suitable examples of α-olefins having 3-8 carbon atoms include, but are not limited to, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, and 1-octene. More preferably, the α-olefin in the ethylene-α-olefin copolymer is selected from α-olefins having 3-4 carbon atoms and any mixture thereof, and more preferably, the α-olefin is propylene, in which case the ethylene-α-olefin copolymer is an ethylene-propylene copolymer.

[0127] MFI of dispersed ethylene α-olefin copolymer (before incorporating multiphase propylene copolymer into the composition), MFI 橡胶 This can be, for example, at least 0.001 dg / min, at least 0.01 dg / min, at least 0.1 dg / min, at least 0.3 dg / min, at least 0.7 dg / min, at least 1 dg / min, and / or, for example, at most 30 dg / min, at most 20 dg / min, at most 15 dg / min, at most 10 dg / min, at most 5 dg / min, or at most 3 dg / min. MFI 橡胶 This could be, for example, 0.001-30 dg / min, 0.01-20 dg / min, 0.1-15 dg / min, 0.3-10 dg / min, 0.7-5 dg / min, or 1-3 dg / min. MFI 橡胶 Calculate according to the following formula:

[0128]

[0129] in

[0130] MFI 多相 The MFI (dg / min) of the multiphase propylene copolymer was measured according to ISO 1133 (2.16 kg / 230 °C).

[0131] MFI 基质 The MFI (dg / min) based on a propylene matrix was measured according to ISO 1133 (2.16 kg / 230 °C).

[0132] The matrix content is based on the fraction of propylene matrix in the multiphase propylene copolymer.

[0133] The rubber content is the fraction of dispersed ethylene-α-olefin copolymer in the multiphase propylene copolymer. The sum of the matrix content and the rubber content is 1. To avoid any ambiguity, Log in the formula represents log... 10 .

[0134] The amount of dispersed ethylene-α-olefin copolymer present is 50-5% by weight based on the total amount of multiphase propylene copolymer. Preferably, the amount of dispersed ethylene-α-olefin copolymer present is 40-15% by weight, for example, at least 22% by weight and / or for example, at most 35% by weight, or at most 30% by weight, based on the total amount of multiphase propylene copolymer.

[0135] In the multiphase propylene copolymer of the composition, the sum of the total weight of the propylene-based matrix and the total weight of the dispersed ethylene-α-olefin copolymer is 100% of the weight of the multiphase propylene copolymer.

[0136] The α-olefin in the ethylene-α-olefin copolymer is preferably selected from α-olefins having 3-8 carbon atoms and any mixture thereof, more preferably from α-olefins having 3-4 carbon atoms and any mixture thereof, and more preferably from propylene, in which case the ethylene-α-olefin copolymer is an ethylene-propylene copolymer. Examples of suitable α-olefins having 3-8 carbon atoms that can be used as ethylene comonomers to form ethylene-α-olefin copolymers include, but are not limited to, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, and 1-octene.

[0137] The density of elastomers of ethylene and α-olefin comonomers having 4-8 carbon atoms can be, for example, 0.850-0.915 g / cm³. 3 Such elastomers are sometimes also called plastic bodies.

[0138] The α-olefin comonomer in the elastomer is preferably an acyclic monoolefin, such as 1-butene, 1-pentene, 1-hexene, 1-octene, or 4-methylpentene.

[0139] Therefore, the elastomer is preferably selected from ethylene-1-butene copolymers, ethylene-1-hexene copolymers, ethylene-1-octene copolymers, and mixtures thereof, more preferably wherein the elastomer is selected from ethylene-1-octene copolymers. Most preferably, the elastomer is an ethylene-1-octene copolymer.

[0140] Preferably, the density of the elastomer is at least 0.865 g / cm³. 3 And / or at most 0.910 g / cm³ 3 For example, the density of the elastomer is at least 0.850, for example at least 0.865, for example at least 0.88, for example at least 0.90, and / or for example at most 0.915, for example at most 0.910, for example at most 0.907, for example at most 0.906 g / cm³. 3 More preferably, the density of the elastomer is 0.88 up to and including 0.907 g / cm³. 3The density of the preferred elastomer is 0.90 up to and including 0.906 g / cm³. 3 .

[0141] The elastomers suitable for use in this invention are commercially available, for example, under the trademark EXACT. TM Acquired from Exxon Chemical Company in Houston, Texas, USA, or under the trademark ENGAGE. TM The polymer (a series of metallocene-catalyzed plastics) was sourced from Dow Chemical Company in Midland, Michigan, USA, or under the trademark TAFMER. TM Obtained from MITSUI Chemicals Group in Minato Ward, Tokyo, Japan, or under the trademark Nexlene. TM Obtained from SK Chemicals.

[0142] Elastomers can be prepared using methods known in the art, such as using single-site catalysts, i.e., catalysts in which the transition metal component is an organometallic compound and at least one ligand has a cyclopentadienyl anionic structure, through which the ligand is coordinated to the transition metal cation. This type of catalyst is also known as a "metallocene" catalyst. Metallocene catalysts are described, for example, in U.S. Patent Nos. 5,017,714 and 5,324,820. Elastomers can also be prepared using conventional types of heterogeneous multisite Ziegler-Natta catalysts.

[0143] Preferably, the melt flow index of the elastomer is 0.1-40 dg / min (ISO 1133, 2.16 kg, 190 °C), for example, at least 1 dg / min and / or at most 35 dg / min. More preferably, the melt flow index of the elastomer is at least 1.5 dg / min, for example, at least 2 dg / min, for example, at least 2.5 dg / min, for example, at least 3 dg / min, more preferably at least 5 dg / min, and / or preferably at most 30 dg / min, more preferably at most 20 dg / min, more preferably at most 10 dg / min, measured according to ISO 1133 using a weight of 2.16 kg and a temperature of 190 °C.

[0144] Preferably, the amount of ethylene introduced into the elastomer is at least 50 mol%. More preferably, the amount of ethylene introduced into the elastomer is at least 57 mol%, for example at least 60 mol%, at least 65 mol%, or at least 70 mol%. Even more preferably, the amount of ethylene introduced into the elastomer is at least 75 mol%. The amount of ethylene introduced into the elastomer can typically be up to 97.5 mol%, for example up to 95 mol%, or up to 90 mol.

[0145] In a preferred embodiment, the thermoplastic polymer in the thermoplastic polymer composition is a propylene homopolymer.

[0146] In a preferred embodiment, the thermoplastic polymer is non-thickness-reducing cracked polypropylene, also known as reactor-grade. This achieves better odor properties than thickened cracked polypropylene, which is manufactured by thickening and cracking reactor-grade polypropylene, which has a low melt flow index, to increase its melt flow index.

[0147] Additives in thermoplastic polymer compositions of polymer sheaths

[0148] The thermoplastic polymer composition of the polymer sheath may contain other commonly used additives, such as nucleating and clarifying agents, stabilizers, fillers, plasticizers, antioxidants, lubricants, antistatic agents, scratch-resistant agents, impact modifiers, acid scavengers, recycling additives, coupling agents, antimicrobial agents, antifogging additives, slip additives, anti-caking additives, polymer processing aids, flame retardants, colorants, etc. Such additives are well known in the art. Those skilled in the art know how to select the type and amount of additives so that they do not adversely affect the target properties. The amount of additives may, for example, be 0.1-5.0% by weight of the thermoplastic polymer composition. The amount of additives may, for example, be 0.1-50% by weight of the thermoplastic polymer composition.

[0149] In some preferred embodiments, the additives in the thermoplastic polymer composition of the polymer sheath include flame retardants. Flame retardants may include organic flame retardants and / or inorganic flame retardants.

[0150] The organic flame retardant preferably comprises at least one phosphate ester selected from the following: melamine phosphate, melamine polyphosphate, melamine pyrophosphate, piperazine phosphate, piperazine polyphosphate, piperazine pyrophosphate, 2-methylpiperazine monophosphate, tricresyl phosphate, alkyl phosphate, haloalkyl phosphate, tetraphenyl pyrophosphate, poly(2-hydroxypropylene spirocyclopentaerythritol diphosphate), and poly(2,2-dimethylpropylene spirocyclopentaerythritol diphosphonate).

[0151] The organic flame retardant preferably comprises ammonium polyphosphate. In some preferred embodiments, the organic flame retardant comprises ammonium polyphosphate and at least one of the aforementioned phosphate esters.

[0152] In some preferred embodiments, the organic flame retardant comprises ammonium polyphosphate and at least two of the aforementioned phosphate esters.

[0153] In some preferred embodiments, the organic flame retardant comprises ammonium polyphosphate, melamine polyphosphate, and piperazine phosphate.

[0154] In some preferred embodiments, the organic flame retardant comprises melamine phosphate and piperazine pyrophosphate.

[0155] Inorganic flame retardants may include, for example, zinc oxide.

[0156] In some preferred embodiments, the flame retardant may be granules comprising an organic flame retardant and zinc oxide. Preferably, the amount of zinc oxide relative to the granules is 1-10% by weight.

[0157] In some preferred embodiments, the organic flame retardant comprises an aromatic phosphate ester.

[0158] In some preferred embodiments, the amount of flame retardant, particularly organic flame retardant, is 0.1-50% by weight, for example at least 1.0% by weight, at least 5.0% by weight, at least 10% by weight, at least 20% by weight, at least 30% by weight, and / or at most 45% by weight, or at most 40% by weight, relative to the thermoplastic polymer composition of the polymer sheath.

[0159] The aforementioned flame retardants, particularly phosphate esters, can be used as part of an intumescent flame retardant composition. The intumescent flame retardant composition can contain various components to produce an external char coating upon exposure to flame and / or high heat. The thermoplastic polymer composition containing the intumescent flame retardant includes a carbon source, and the composition can include a film-forming binder, an acid source, and a foaming agent. The carbon source can be an organic material that decomposes into char, primarily composed of carbon, upon exposure to fire or heat. The carbon source can be a polyolefin in the thermoplastic polymer composition. In the presence of an acid source that promotes char formation and a foaming agent that expands the char, the carbon source can produce an expanded, insulating cellular structure that can be several times thicker than its original thickness upon exposure to fire or heat.

[0160] In some preferred embodiments, the additives in the thermoplastic polymer composition of the polymer sheath include a coupling agent.

[0161] Suitable examples of coupling agents include functionalized polyolefins grafted with acid or anhydride functional groups. The polyolefin is preferably polyethylene or polypropylene, more preferably polypropylene. The polypropylene can be a propylene homopolymer or a propylene copolymer. The propylene copolymer can be a propylene-α-olefin copolymer comprising at least 70% by weight of propylene and at most 30% by weight of an α-olefin (e.g., ethylene), for example, at least 80% by weight of propylene and at most 20% by weight of an α-olefin, for example, at least 90% by weight of propylene and at most 10% by weight of an α-olefin, based on the total weight of the propylene-based matrix. Preferably, the α-olefin in the propylene-α-olefin copolymer is selected from α-olefins having 2 or 4-10 carbon atoms, preferably ethylene. Examples of acid or anhydride functional groups include (meth)acrylic acid and maleic anhydride. A particularly suitable material is, for example, maleic acid-functionalized propylene homopolymers (e.g., Exxelor PO1020 supplied by ExxonMobil and Fine-Blend® CMG5701 supplied by Fine-Blend Compatibilizer Jiangsu Co., Ltd.). In particular, maleic acid-functionalized propylene homopolymers with low odor and TVOC are preferred, an example being Fine-Blend® CMG5701.

[0162] The amount of coupling agent can be, for example, 0.5-3.0% by weight, preferably 1.0-2.0% by weight, based on the continuous multi-fiber strands with sheath.

[0163] core

[0164] The sheathed continuous multifiber strand includes a longitudinally extending core. The core comprises an impregnated continuous bicomponent multifiber strand, which includes at least one continuous bicomponent multifiber strand and an impregnating agent. The impregnated continuous bicomponent multifiber strand is prepared by impregnating the continuous bicomponent multifiber strand with the impregnating agent.

[0165] Preferably, the sum of the impregnated continuous bicomponent multifiber strands and any impregnated continuous glass multifiber strands forms at least 90% by weight, more preferably at least 93% by weight, even more preferably at least 95% by weight, even more preferably at least 97% by weight, even more preferably at least 98% by weight, for example at least 99% by weight. In a preferred embodiment, the core is composed of impregnated continuous bicomponent multifiber strands and any impregnated continuous glass multifiber strands.

[0166] In the context of this invention, "longitudinal extension" means "orientation along the long axis of a continuous multifilament strand in a sheath".

[0167] Continuous bicomponent multifiber strands of core

[0168] Continuous bicomponent multifilament strands containing composite filaments are typically supplied as multiple continuous, very long filaments and can be in the form of strands, rovings, or yarns. A filament is a single fiber of reinforcing material. A strand is multiple bundles of filaments. Yarn is a collection of strands, such as strands twisted together. Rovings refer to a collection of strands wound into a spool.

[0169] For the purposes of this invention, multi-fiber strands are defined as multiple bundled composite fibers.

[0170] The fiber density of continuous bicomponent multifiber strands can vary over a wide range. For example, continuous bicomponent multifiber strands can have a density of 1,000-10,000 g / 1,000 m.

[0171] Preferably, the continuous bicomponent multifiber strand has a density of 1000-2900 g / 1000 m, more preferably 1500-2800 g / 1000 m.

[0172] Continuous bicomponent multifilament strands can have a filament diameter of 5-50 μm, more preferably 10-30 μm, and even more preferably 15-25 μm. The cross-section of the bicomponent filament can be circular, meaning that the thickness as defined above will represent the diameter.

[0173] Preferably, the ratio of the length to the diameter of the bicomponent filaments in the granules (L / D ratio) is 500-1000.

[0174] Preferably, the bicomponent multifilament strands are coated with an sizing composition (i.e., a coating) to improve adhesion to the polymer matrix. The sizing composition may be applied to substantially all or a portion of the bicomponent filaments in the thermoplastic composition. Sizing provides coated bicomponent filaments that may or may not be bonded to the bicomponent thermoplastic polymer composition of the sheath. Preferably, the coated bicomponent filaments are bonded towards the polymer in the thermoplastic polymer composition of the sheath.

[0175] The sizing composition may comprise polyepoxides, poly(meth)acrylates, poly(aryl ethers), polyurethanes, or combinations thereof. The polyepoxide may be a phenolic epoxy resin, an epoxidized carboxylic acid derivative (e.g., a reaction product of an ester of a polycarboxylic acid having one or more unesterified carboxyl groups and a compound containing more than one epoxy group), an epoxidized diene polymer, an epoxidized polyene polymer, or a combination thereof.

[0176] The sizing composition may further include a silane coupling agent to promote bonding with the glass fibers. The silane coupling agent may be tri(C) 1-6 Alkoxy) monoaminosilane, tri(C 1-6 Alkoxy)diaminosilane, tri(C 1-6 Alkoxy)(C1-6 Alkylurea)silane, tri(C 1-6 Alkoxy (epoxy C) 1-6 Alkyl)silane, tri(C) 1-6 Alkoxy (epoxypropoxy C) 1-6 Alkyl)silane, tri(C) 1-6 Alkoxy (Mercapto C) 1-6 Alkyl)silanes or combinations thereof. For example, silane coupling agents are (3-aminopropyl)triethoxysilane, (3-epoxypropoxypropyl)trimethoxysilane, (2-(3,4-epoxycyclohexyl)ethyl)triethoxysilane, (3-mercaptopropyl)trimethoxysilane, (3-(2-aminoethylamino)propyl)triethoxysilane, (3-ureopropyl)triethoxysilane, or combinations thereof. Preferably, the silane coupling agent is aminopropyltriethoxysilane, glycidylpropyltrimethoxysilane, or combinations thereof.

[0177] Other materials that can be included in the sizing composition include, but are not limited to, antistatic agents, coupling agents, lubricants, wetting agents, etc.

[0178] The amount of the sizing composition may be 0.1-5.0% by weight based on at least one continuous bicomponent multifiber strand. The sizing composition can be applied to the composite filament by any means, such as immersing the multifiber strand in the sizing composition or contacting the multifiber strand with an aqueous emulsion or suspension of the sizing composition. Other coating methods include applying an aqueous dispersion of the sizing composition continuously to the uncoated multifiber strand using a roller, followed by a heat treatment or curing step.

[0179] Typically, after the sizing composition is applied to the filaments, the filaments are bundled into continuous bicomponent multifilament strands and then wound onto a spool to form a package.

[0180] The above description of the sizing composition applies to both bicomponent filaments and glass fibers.

[0181] Impregnating agent

[0182] The amount of impregnating agent is preferably 0.50-18.0% by weight, for example 0.5-10.0% by weight, or for example 10.0-18.0% by weight, based on the total weight of the granules.

[0183] The optimal amount of impregnating agent depends on the polymer sheath, the size (diameter) of the filaments forming the continuous strand, and the type of sizing composition. Typically, the amount of impregnating agent applied to the continuous multifilament strand is, for example, at least 0.50 wt%, preferably at least 1.0 wt%, preferably at least 1.5 wt%, preferably at least 2 wt%, preferably at least 2.5 wt%, and / or up to 10.0 wt%, preferably up to 9.0 wt%, more preferably up to 8.0 wt%, even more preferably up to 7.0 wt%, even more preferably up to 6.0 wt%, even more preferably up to 5.5 wt%, or for example, at least 10.0 wt%, preferably at least 11 wt%, preferably at least 12 wt%, and / or up to 18 wt%, preferably up to 16 wt%. Preferably, it is up to 14 wt%, based on the amount of the sheathed continuous multifilament strand. Preferably, the amount of impregnating agent is 1.5-8.0 wt%, even more preferably 2.5 wt%-6.0 wt%, based on the sheathed continuous multifilament strand. A higher amount of impregnating agent increases the impact energy (J / mm) per unit thickness. However, for cost-effectiveness, low emissions (volatile organic compounds), and mechanical properties, the amount of impregnating agent should not be too high. For example, the ratio of impregnating agent to continuous glass multifiber strands is 1:4 to 1:30, preferably 1:5 to 1:20.

[0184] Preferably, the viscosity of the impregnating agent at 160°C is 2.5-200 cSt, more preferably at least 5.0 cSt, more preferably at least 7.0 cSt, and / or at most 150.0 cSt, more preferably at most 125.0 cSt, and more preferably at most 100.0 cSt.

[0185] Impregnating agents with a viscosity higher than 200 cSt are difficult to apply to continuous glass multifiber strands. Low viscosity is required to promote good fiber wettability, but impregnating agents with a viscosity lower than 2.5 cSt are difficult to handle, for example, it is difficult to control the amount applied; and the impregnating agent becomes volatile. For the purposes of this invention, unless otherwise stated, the viscosity of the impregnating agent is measured at 160°C according to ASTM D3236-15 (Standard Test Method for Apparent Viscosity of Hot Melt Adhesives and Coatings, Brookfield Viscometer Model RVDV2, #27 Rotor, 5 r / min).

[0186] Preferably, the melting point of the impregnating agent (which is the lowest melting temperature in the melting temperature range) is at least 20°C lower than the melting point of the thermoplastic polymer composition. More preferably, the melting point of the impregnating agent is at least 25°C or 30°C lower than the melting point of the thermoplastic polymer composition. For example, when the melting point of the thermoplastic polymer composition is about 160°C, the melting point of the impregnating agent can be at most about 140°C.

[0187] A suitable impregnating agent is compatible with, or even soluble in, the thermoplastic polymer to be reinforced. Those skilled in the art can select a suitable combination based on common sense, and such combinations will be found in the art.

[0188] Suitable examples of impregnating agents include low molar mass compounds, such as low molar mass oligomeric polyurethanes, polyesters such as unsaturated polyesters, polycaprolactone, polyethylene terephthalate, poly(α-olefins) such as highly branched polyethylene and polypropylene, polyamides such as nylon, and other hydrocarbon resins.

[0189] For reinforced polypropylene, the impregnating agent preferably comprises highly branched poly(α-olefin), such as highly branched polyethylene, modified low molecular weight polypropylene, mineral oil, such as paraffin or silicone, and any mixture of these compounds.

[0190] The impregnating agent preferably contains at least 20% by weight, more preferably at least 30% by weight, even more preferably at least 50% by weight, for example at least 99.5% by weight, for example 100% by weight, of a branched poly(α-olefin), most preferably branched polyethylene. To achieve a viscosity of 2.5-200 cSt at 160°C, the branched poly(α-olefin) can be mixed with an oil selected from mineral oils, such as paraffin oil or silicone oil; hydrocarbon oils; and any mixtures thereof.

[0191] Preferably, the impregnating agent is non-volatile and / or substantially solvent-free. In the context of this invention, non-volatile means that the boiling point or boiling point range of the impregnating agent is above the temperature at which the impregnating agent is applied to a continuous multi-filament glass strand. In the context of this invention, "substantially solvent-free" means that the impregnating agent contains less than 10% by weight of solvent, preferably less than 5% by weight, based on the amount of impregnating agent. In a preferred embodiment, the impregnating agent does not contain any organic solvents.

[0192] The impregnating agent can be further mixed with other additives known in the art. Suitable examples include lubricants; antistatic agents; UV stabilizers; plasticizers; surfactants; nucleating agents; antioxidants; pigments; dyes; and adhesion promoters, such as modified polypropylene with maleic acid reactive groups; and any combination thereof, provided that the viscosity is within the desired range. The impregnating agent can be applied to continuous glass multifiber strands using any method known in the art. The application of the impregnating agent can be performed using a mold. Other suitable methods for applying the impregnating agent to continuous multifiber strands include applicators with belts, rollers, and hot-melt applicators. Such methods are described, for example, in documents EP0921919B1, EP0994978B1, EP0397505B1, WO2014 / 053590A1, and the references cited therein. The method used should be able to apply a constant amount of impregnating agent to continuous multifiber strands.

[0193] The above instructions for impregnating agents apply to both two-component multifiber strands and glass multifiber strands.

[0194] The weight-average length of composite filaments in granules or molded articles can be determined, for example, by creating photographic images of the granules or articles to allow image processing algorithms to detect the length of all individual filaments in the image, and calculating the weight-average length from the detected lengths. The photographic images can be produced, for example, by incinerating the granules or articles and photographing the ash under an optical microscope. This can be accomplished, for example, by incinerating the granules or articles at a temperature of 700°C, gently spreading the ash obtained from incineration using a brush, and photographing the spread ash under an optical microscope. The length of individual filaments in the granules can also be determined by directly measuring the length of the granules.

[0195] The weight-average length of composite fibers can be calculated using the following formula:

[0196]

[0197] in L w It is the weight-average length of the composite filament.

[0198] l i It refers to the length of a single composite filament.

[0199] It should be noted that the present invention relates to a combination of the subject matter individually defined in the independent claims or any possible combination of the features described herein, with particular preference for those combinations of features present in the claims. Therefore, it should be understood that this document describes all combinations of features related to the compositions according to the invention; all combinations of features related to the methods according to the invention; and all combinations of features related to the compositions according to the invention and the methods according to the invention.

[0200] It should be further noted that the term "comprising / including" does not exclude the presence of other elements. However, it should also be understood that a description of a product / composition comprising certain components also discloses a product / composition composed of those components. A product / composition composed of these components may be advantageous because it provides a simpler and more economical method for preparing the product / composition. Similarly, it should be understood that a description of a method including certain steps also discloses a method composed of those steps. A method composed of these steps may be advantageous because it provides a simpler and more economical method.

[0201] The present invention will now be illustrated by the following embodiments, but is not limited thereto.

[0202] Example

[0203] Materials used

[0204] GF1: A glass roving with a diameter of 19 micrometers and a density of 3000 tex (tex means grams of glass per 1000m), containing a sizing composition comprising a silane coupling agent.

[0205] GF2: A roving with a diameter of 19 micrometers and a density of 2200 tex, wherein the roving consists of bundles of composite filaments of basalt filaments in contact with aluminum filaments, and contains a sizing composition comprising a silane coupling agent and polyurethane.

[0206] Impregnating agent 1: A wax that can be commercially available as IGI Paraflex 4838A.

[0207] PP1: SABIC PP 595A polypropylene homopolymer with the following properties: Density: 905 kg / m³ 3 Melt flow index at 230℃ and 2.16 kg: 45 dg / min (Test method: ISO 1133).

[0208] Exxelor PO1020: Maleic anhydride-grafted polypropylene from ExxonMobil: Density: 900 kg / m³ 3 Melting point: 162℃; melt flow index at 230℃ and 2.16 kg: 430 dg / min (test method: ASTM D1238).

[0209] AOB225: Antioxidant B225 from BASF

[0210] UV119: UV stabilizer UV 119 from SABO SpA

[0211] Using the wire coating method detailed in the examples such as WO 2009 / 080281A1, granules of sheathed continuous glass multifiber strands are prepared using the components given in Table 1.

[0212] Impregnating agent 1 is applied to GF1 to obtain impregnated continuous glass multifiber strands.

[0213] The polypropylene and additives shown in Table 1 were fed into an extruder to sheath the impregnated continuous glass multifiber strands using an extruder head wire coating die. The sheathing step was performed online directly after the impregnation step. The resulting sheathed continuous multifiber strands were cut into granules of 8-15 mm length and 3-4 mm diameter. The resulting granules were then molded using an ARBURG320T injection molding machine to prepare test samples.

[0214] Ex2 and Ex4

[0215] Sheathed, continuous multifiber granules were prepared using the method described in CEx1 and the components given in Table 1.

[0216] The following performance was measured and is shown in Table 1.

[0217] Flexural properties were tested according to ISO 178 after aging at 23°C for 7 days.

[0218] Tensile properties were tested according to ISO 527 after aging at 23°C for 7 days.

[0219] The performance of the simply supported beam (Charpy) was tested according to ISO 179 / 1eU after aging at 23°C for 7 days.

[0220] Shielded Dk / Df signals were tested on a molded plate in the 30-100MHz and 100-1000MHz ranges. The signal strength loss as a function of frequency was recorded.

[0221] The weight-average filament length of the filaments in the injection-molded plate is determined by collecting ash by heating the sample, dispersing the ash residue in a liquid, and then analyzing it with a microscope equipped with imaging software.

[0222] Table 1

[0223]

[0224] It is understandable that the compositions of Ex2 and 4, made from long composite fibers of basalt and aluminum fibers, have better shielding performance than the compositions of CEx1 and CEx3, made from glass fibers.

Claims

1. Granules comprising a fiber-reinforced thermoplastic polymer composition comprising a thermoplastic polymer and a plurality of composite filaments, Each composite filament comprises a first filament and a second filament. The first filament is composed of an inorganic material and has a glass transition temperature greater than or equal to 400°C. The second filament is composed of a metallic material and is in contact with the first filament. The weight-average length of the composite fibers in the granules is at least 5.0 mm.

2. The granules according to claim 1, wherein The first filament is a glass filament or a basalt filament, and The second filament has an aluminum content of at least 98 wt%, at least 99 wt%, or at least 99.5 wt%, or a copper content of at least 98 wt%, at least 99 wt%, or at least 99.5 wt%, preferably an aluminum content of at least 98 wt%, at least 99 wt%, or at least 99.5 wt%.

3. The granules according to any one of the preceding claims, wherein the thermoplastic polymer is polypropylene.

4. The pellets according to any one of the preceding claims, wherein the pellets further comprise a flame retardant.

5. The granules according to any one of claims 1-4, wherein the filaments in the granules are composed of composite filaments.

6. The granules according to any one of claims 1-4, wherein the granules further comprise glass fibers, wherein the weight ratio of composite fibers to glass fibers is 10:90-90:

10.

7. The pellets according to any one of claims 1-6, wherein the pellets comprise a sheathed continuous multifilament strand, the sheathed continuous multifilament strand comprising a longitudinally extending core and a polymer sheath tightly surrounding the core. The core comprises an impregnated continuous bicomponent multifiber strand, the impregnated continuous bicomponent multifiber strand comprising at least one continuous bicomponent multifiber strand containing bundles of multiple composite filaments, and The polymer sheath is composed of a thermoplastic polymer composition containing a thermoplastic polymer.

8. The granules according to claim 7, wherein the weight-average length of the composite filaments in the granules is substantially the same as the length of the granules, and is 10-55 mm, preferably 10-40 mm, more preferably 10-30 mm, and most preferably 10-20 mm.

9. The granules according to any one of claims 1-6, wherein a plurality of composite filaments are dispersed in a thermoplastic polymer matrix.

10. The granules according to claim 9, wherein the weight-average length of the composite filaments in the granules is substantially the same as the length of the granules, and is 5.0-10 mm, preferably 5.0-8.0 mm.

11. A molded article manufactured by injection molding of granules according to any one of claims 1-10 and optionally granules comprising a thermoplastic composition comprising a thermoplastic polymer and optionally glass filaments, wherein the composite filaments in the article have a weight-average length of at least 1.0 mm, preferably 1.0-2.0 mm, for example 1.3-1.7 mm.

12. A molded article manufactured by extruding granules according to any one of claims 1-10 and optionally granules comprising a thermoplastic composition comprising a thermoplastic polymer and optionally glass filaments, wherein the composite filaments in the article have a weight-average length of at least 0.5 mm, preferably at least 1.0 mm, preferably 1.0-2.0 mm, for example 1.3-1.7 mm.

13. The molded article according to claim 11 or 12, wherein the molded article is selected from battery casings, battery trays, battery charging stations, power tools, building and structural shielding boxes, scaffolding, structural frames, and floors.

14. A method for preparing granules according to claim 7 or 8, the method comprising the following sequential steps: a) Unwinding from at least one continuous bicomponent multifiber strand package b) Applying an impregnating agent to at least one continuous bicomponent multifiber strand to form an impregnated continuous bicomponent multifiber strand. c) Applying a thermoplastic polymer sheath around an impregnated continuous multifiber strand to form a sheathed continuous multifiber strand, and d) Cut the strands into granules.

15. A method for preparing granules according to claim 9 or 10, the method comprising the following sequential steps: i) Unwinding from at least one continuous bicomponent multifiber strand package. ii) Spread at least one continuous bicomponent multifilament strand into a single composite filament. iii) Drawing composite filaments through a melt of a thermoplastic polymer composition containing a thermoplastic polymer to impregnate the composite filaments with the thermoplastic polymer to obtain strands, wherein the composite filaments are dispersed in a thermoplastic polymer matrix, and iv) Cut the strands to obtain pellets.

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