High-strength high-impact polypropylene composite sheet and fabric thereof, polypropylene composite material, and method and application thereof

Abstract

This invention relates to the field of polypropylene materials, and discloses a polypropylene composite sheet, a polypropylene fabric, a polypropylene composite material, its preparation method, and its applications. The polypropylene composite sheet includes a film layer A containing a polypropylene composition A, a film layer B containing a polypropylene composition B, and a film layer C containing a polypropylene composition C; it has a CBABC sheet structure; the two film layers B on both sides may be the same or different, and the two film layers C on both sides may be the same or different. Polypropylene composition A includes homopolymer polypropylene a and impact copolymer polypropylene b; polypropylene composition B includes random copolymer polypropylene β and homopolymer polypropylene γ; polypropylene composition C includes random copolymer polypropylene x; polypropylene compositions B and C independently contain a heat-bonding reinforcing agent. The polypropylene composite material obtained from this polypropylene sheet possesses both excellent tensile and impact properties, and maintains good interlaminar peel strength even when prepared at relatively low hot-pressing temperatures.

Description

Technical Field

[0001] This invention relates to the field of polypropylene materials, and more specifically, to a high-strength, high-impact polypropylene composite sheet and its fabric, polypropylene composite materials, and their preparation and application. Background Technology

[0002] Currently, high-strength, high-impact polymer composites that are easily recyclable and lightweight, especially those with self-reinforcing properties, have become a research hotspot. The matrix and reinforcing phase of self-reinforcing polymer composites are composed of the same polymer in different forms. Typically, the reinforcing phase is highly oriented fibers or ribbons.

[0003] Currently, most self-reinforced polymer composites are prepared using hot pressing. When the reinforcing phase is hot-pressed under certain pressure and temperature, the surface of the fibrous reinforcing phase melts into the matrix melt. The matrix melt and the reinforcing phase melt co-crystallize on the surface during melting, resulting in a strong bond between them, which can further improve the interfacial bonding strength. For example, in US6312638B1, polyolefin fibers are hot-pressed, using specific temperature and pressure to partially melt and bond the surface layer of the melt-spun oriented polyolefin together, thereby preparing a polyolefin board. However, this preparation method is not only sensitive to the temperature of hot pressing (high temperature and narrow range), but also causes the spun oriented fibers to decompose after hot pressing, resulting in a significant decrease in fiber mechanical strength and poor self-reinforcing effect.

[0004] Patent document US8268439B2 describes a polyolefin composite material obtained by hot-pressing three layers of polyolefins with different melting points and morphologies. The first and third layers are oriented polyolefin layers, and the second layer is a low-melting-point polyolefin film base layer. Furthermore, the melting temperature of the second base layer polyolefin is lower than that of the first and third layers. This design of different melting points in each layer can widen the hot-pressing window and reduce the hot-pressing pressure; however, the impact strength and interlaminar peel strength of the hot-pressed composite material produced by this method are relatively low. Summary of the Invention

[0005] The purpose of this invention is to overcome the difficulty of existing polypropylene composite materials simultaneously possessing a wide processing temperature range, strong mechanical properties, and high interlaminar peel strength. A method for preparing a high-strength, high-impact polypropylene composite material is provided. The polypropylene composite material obtained by this method exhibits excellent mechanical properties, while also possessing good interlaminar peel strength at a relatively low hot-pressing temperature and over a wide hot-pressing temperature range.

[0006] One objective of this invention is to provide a polypropylene composite sheet, comprising a film layer A containing a polypropylene composition A, a film layer B containing a polypropylene composition B, and a film layer C containing a polypropylene composition C; the polypropylene composite sheet has a CBABC layer structure, with film layer A as the center, and film layers B and C located sequentially on both sides of film layer A from the inside out; film layers B on both sides of film layer A may be the same or different, and film layers C on both sides of film layer A may be the same or different; wherein, polypropylene composition A comprises homopolymer polypropylene a and impact copolymer polypropylene b; polypropylene composition B comprises random copolymer polypropylene β and homopolymer polypropylene γ; polypropylene composition C comprises random copolymer polypropylene x; and polypropylene compositions B and C independently contain a thermal bonding enhancer.

[0007] According to the present invention, the thin film layers B on both sides of thin film layer A may be the same or different, and the thin film layers C on both sides of thin film layer A may be the same or different. In a preferred embodiment of the present invention, the thin film layers B on both sides of thin film layer A are the same, and / or the thin film layers C on both sides of thin film layer A are the same.

[0008] According to the present invention, the content of each component in the polypropylene composition A can be selected within a wide range. In a preferred embodiment of the present invention, based on the total weight of the polypropylene composition A, the polypropylene composition A comprises 50-99 wt% homopolymer polypropylene a and 1-50 wt% impact copolymer polypropylene b; preferably, the polypropylene composition A comprises 70-90 wt% homopolymer polypropylene a and 10-30 wt% impact copolymer polypropylene b.

[0009] According to the present invention, the content of each component in the polypropylene composition B can be selected within a wide range. In a preferred embodiment of the present invention, based on the total weight of the polypropylene composition B, the polypropylene composition B comprises 30-60 wt% of a heat-bonding reinforcing agent, 35-55 wt% of random copolymer polypropylene β, and 5-15 wt% of homopolymer polypropylene γ; preferably, the polypropylene composition B comprises 35-55 wt% of a heat-bonding reinforcing agent, 40-55 wt% of random copolymer polypropylene β, and 5-10 wt% of homopolymer polypropylene γ.

[0010] The content of each component in the polypropylene composition C can be selected within a wide range. In a preferred embodiment of the present invention, based on the total weight of the polypropylene composition C, the polypropylene composition C includes 70-99 wt% random copolymer polypropylene x and 1-30 wt% heat-bonding reinforcing agent; preferably, the polypropylene composition C includes 80-90 wt% random copolymer polypropylene x and 10-20 wt% heat-bonding reinforcing agent.

[0011] According to the present invention, the selection range of the thickness percentage of each film layer is relatively wide. In a preferred embodiment of the present invention, based on the total thickness of the polypropylene composite sheet, the thickness of film layer A accounts for 51%-89% of the total thickness, preferably 71%-89%; the thickness of polypropylene film layer B accounts for 6%-20% of the total thickness, preferably 6%-15%; and the thickness of polypropylene film layer C accounts for 5%-30% of the total thickness, preferably 5%-15%. The thicknesses of film layers B on both sides of film layer A can be the same or different, preferably the same; the thicknesses of film layers C on both sides of film layer A can be the same or different, preferably the same.

[0012] The thickness of the polypropylene sheet is not limited and can be selected within a wide range according to its actual application. Preferably, the thickness of the polypropylene sheet can be 10-1000μm, more preferably 30-500μm, and even more preferably 50-300μm.

[0013] According to the present invention, the thickness of film layers A, B, and C can be controlled by the extruder melt pump during the processing.

[0014] According to the present invention, the homopolymer polypropylene a has a wide range of material selection. In a preferred embodiment of the present invention, the melting point of the homopolymer polypropylene a is 160-170°C; and / or, the melt flow rate of the homopolymer polypropylene a at 190°C and 2.16 kg load is 0.5-50 g / 10 min, preferably 1-20 g / 10 min, more preferably 2.5-18 g / 10 min; and / or, the isotacticity (mm) of the homopolymer polypropylene is not less than 96%.

[0015] According to the present invention, "and / or" refers to either a single condition or a combination of two conditions.

[0016] According to the present invention, the selection range of the impact-resistant copolymer polypropylene b is relatively wide. In a preferred embodiment of the present invention, the monomer for copolymerizing the impact-resistant copolymer polypropylene b with propylene is ethylene or butene, preferably butene; and / or, the melting point of the impact-resistant copolymer polypropylene b is 150-170℃; and / or, the melt flow rate of the impact-resistant copolymer polypropylene b at 190℃ and 2.16kg load is 0.5-50g / 10min, preferably 1-20g / 10min, more preferably 2.5-18g / 10min; and / or, the cantilever beam impact strength of the impact-resistant copolymer polypropylene b is not less than 20KJ / m. 2 (Tested at 23℃).

[0017] According to the inventors' research, when the melt flow rate and polymer composition ratio of polypropylene composition A are within the preferred range, the impact-resistant copolymer polypropylene b in the composition can better absorb impact energy, meeting the impact performance requirements and giving the sheet better impact performance. Simultaneously, because the macromolecular chain segments in homopolymer polypropylene a are more regular, crystallization occurs during the sheet preparation process, thus the sheet also has better tensile properties.

[0018] According to the present invention, the random copolymer polypropylene β has a wide range of material selection. In a preferred embodiment of the present invention, the melting point of the random copolymer polypropylene β is 120-140℃; and / or, the melt flow rate of the random copolymer polypropylene β at 190℃ and 2.16kg load is 0.5-50g / 10min, preferably 1-20g / 10min, and more preferably 3-18g / 10min; preferably, the random copolymer polypropylene β is a copolymer of propylene and ethylene and / or butene, preferably an ethylene-propylene-butene terpolymer and / or a propylene-ethylene binary copolymer.

[0019] According to the present invention, the homopolymer polypropylene γ has a wide range of material selection. In a preferred embodiment of the present invention, the melting point of the homopolymer polypropylene γ is 160-170°C; and / or, the melt flow rate of the homopolymer polypropylene γ at 190°C and 2.16 kg load is 0.5-50 g / 10 min, preferably 1-20 g / 10 min, more preferably 2.5-18 g / 10 min; and / or, the isotacticity (mm) of the homopolymer polypropylene γ is not less than 96%.

[0020] According to the present invention, the random copolymer polypropylene x has a wide range of material selection. In a preferred embodiment of the present invention, the melting point of the random copolymer polypropylene x is 120-140℃; and / or, the melt flow rate of the random copolymer polypropylene x at 190℃ and 2.16kg load is 0.5-50g / 10min, preferably 1-20g / 10min, and more preferably 3-18g / 10min; preferably, the random copolymer polypropylene x is a copolymer of propylene and ethylene and / or butene, preferably an ethylene-propylene-butene terpolymer and / or a propylene-ethylene binary copolymer.

[0021] According to the present invention, the range of materials for the thermal bonding reinforcing agent is relatively wide. In a preferred embodiment of the present invention, the melting point or viscous flow temperature of the thermal bonding reinforcing agent is 70-110°C; and / or, the melt flow rate of the thermal bonding reinforcing agent at 190°C and a load of 2.16 kg is 0.5-50 g / 10 min, preferably 1-20 g / 10 min, more preferably 3-18 g / 10 min; preferably, the thermal bonding reinforcing agent is selected from polyolefin elastomers, ethylene propylene diene monomer (EPDM) rubber, SEBS, etc. One or more of SBS, EVA, and petroleum resin; more preferably, the thermal bonding reinforcing agent is a polyolefin elastomer and / or petroleum resin; the polyolefin elastomer is preferably a copolymer elastomer of ethylene and propylene and / or α-olefin; even more preferably, the α-olefin is a C4-C12 α-olefin, more preferably 1-butene and / or 1-octene; the petroleum resin is a C5 and / or C9 hydrogenated petroleum resin, preferably with a softening point of 100-150°C; more preferably, the petroleum resin is a cyclopentadiene type resin.

[0022] According to the inventors' research, when the melt flow rate and polymer composition ratio of polypropylene composition B and polypropylene composition C are within the above-mentioned preferred range, the low-melting-point random copolymer polypropylene and the heat-bonding reinforcing agent in the composition can significantly reduce the hot-pressing temperature and widen the hot-pressing temperature window. Moreover, the heat-bonding reinforcing agent provides good adhesion performance for the sheet and can further improve the interlayer peel strength.

[0023] In a preferred embodiment of the present invention, the polypropylene composition A further contains a β-crystal nucleating agent, wherein the β-crystal nucleating agent is selected from at least one of polycyclic aromatic hydrocarbons, group IIA two-component complexes, aromatic diamides, rare earth compounds, and cyclic dicarboxylate nucleating agents; and / or, based on 100 parts by weight of the total amount of the polypropylene composition A, the content of the β-crystal nucleating agent is 0.01-0.5 parts by weight. Specifically, for example, the content of the β-crystal nucleating agent may be 0.01, 0.05, 0.1, 0.2, 0.3, 0.4, or 0.5 parts by weight.

[0024] In a preferred embodiment of the present invention, the melting point of polypropylene composition A is greater than that of polypropylene composition B and polypropylene composition C. Preferably, the melting point of homopolymer polypropylene a in polypropylene composition A is greater than that of random copolymer polypropylene β in polypropylene composition B and random copolymer x in polypropylene composition C, and the corresponding melting point temperature difference is greater than or equal to 10 degrees Celsius.

[0025] According to the present invention, there are no particular limitations on the melting point difference between polypropylene composition B and polypropylene composition C.

[0026] According to the inventors' research, when the melt flow rate, melting point difference, polymer composition ratio, and polymer composition thickness distribution of polypropylene composition A, polypropylene composition B, and composition C are within the above-mentioned preferred ranges, the sheet preparation process can be made more stable, thereby giving the sheet better uniformity, tensile strength, impact performance, and interlaminar peel strength.

[0027] According to the present invention, the CBABC layer structure of the polypropylene composite sheet can be obtained by co-extruding components including polypropylene composition A, polypropylene composition B and polypropylene composition C.

[0028] The second objective of this invention is to provide a method for preparing the polypropylene composite sheet described above, comprising co-extruding components including polypropylene composition A, polypropylene composition B, and polypropylene composition C; preferably, polypropylene composition A, polypropylene composition B, and polypropylene composition C are co-extruded, cast, calendered, or stretched according to a CBABC structure to obtain the polypropylene composite sheet.

[0029] According to the present invention, the preparation of the polypropylene composition A includes melt blending of components including homopolymer polypropylene a and impact copolymer polypropylene b. The melt blending conditions and equipment for the polypropylene composition A adopt the conditions and equipment for melt blending of polyolefins in the prior art; preferably, the melt temperature is 150-170°C, and the equipment is preferably a twin-screw extruder.

[0030] The preparation of the polypropylene composition B includes melt blending of the components including the heat-bonding reinforcing agent, random copolymer polypropylene β and homopolymer polypropylene γ; the melt blending conditions and equipment of the polypropylene composition B adopt the conditions and equipment of polyolefin melt blending in the prior art, preferably, the melting temperature is 120-170°C, and the equipment is preferably a twin-screw extruder.

[0031] The preparation of the polypropylene composition C includes melt blending of the random copolymer polypropylene x and the thermal bonding reinforcing agent. The melt blending conditions and equipment for the polypropylene composition C adopt the conditions and equipment for melt blending of polyolefins in the prior art. Preferably, the melt temperature is 110-150°C, and the equipment is preferably a twin-screw extruder.

[0032] In a preferred embodiment of the present invention, the temperatures for co-extrusion molding and casting are independently selected from 200-240°C; and / or, the temperature of the calendering roll is 50-70°C.

[0033] In a preferred embodiment of the present invention, the stretching conditions include: a stretching temperature of 90-165°C, preferably 90-140°C, more preferably 90-119°C, and a stretching ratio of 1-15 times; preferably 2-9 times.

[0034] The third objective of this invention is to provide a polypropylene fabric, a three-dimensional polypropylene fabric obtained by weaving the polypropylene composite sheet described above.

[0035] Preferably, the polypropylene fabric is obtained by cutting and weaving the polypropylene composite sheet.

[0036] To facilitate weaving, it is preferable to cut polypropylene composite sheets into polypropylene sheets with a width of 2-5mm, and then weave them into polypropylene fabrics.

[0037] Preferably, the polypropylene fabric has a three-dimensional structure of plain weave, twill weave, and / or satin weave. For example, it can be produced by weaving oriented flat strips according to the designed fabric structure using a commercial loom to obtain plain weave, twill weave, satin weave, and / or other three-dimensional polypropylene fabrics.

[0038] In a more preferred embodiment of the present invention, the polypropylene fabric is a plain weave, twill weave, satin weave, and / or three-dimensional polypropylene fabric obtained by weaving a five-layer co-extruded polypropylene stretch flat strip, and the co-extruded polypropylene stretch flat strip includes at least one film layer A formed of a high-melting-point polypropylene composition A, at least one film layer B formed of a polypropylene composition B, and at least one film layer C formed of a low-melting-point polypropylene composition C, wherein polypropylene composition A includes homopolymer polypropylene a and impact copolymer polypropylene b; polypropylene composition B includes a heat-bonding reinforcing agent, random copolymer polypropylene β, and homopolymer polypropylene γ; polypropylene composition C includes random copolymer polypropylene x and a heat-bonding reinforcing agent, and the structure of the five-layer co-extruded polypropylene composite sheet is CBABC from bottom to top.

[0039] In a preferred embodiment of the present invention, the polypropylene fabric is plain weave.

[0040] The fourth objective of this invention is to provide a polypropylene composite material, which is prepared by hot pressing together multiple layers of the polypropylene composite sheets and / or the polypropylene fabrics described above.

[0041] In a preferred embodiment of the present invention, the polypropylene composite material is prepared by hot pressing multiple layers of the polypropylene composite sheet or the polypropylene fabric.

[0042] In a preferred embodiment of the present invention, the multilayer polypropylene composite sheet is stacked at 0-90° along its respective machine direction (i.e., stretching direction MD) from top to bottom; and / or, the multilayer polypropylene fabric is stacked at 0-90° between warp directions from top to bottom.

[0043] In a preferred embodiment of the present invention, the number of layers of the multilayer polypropylene composite sheet or the polypropylene fabric is preferably greater than or equal to 2 layers, more preferably 2-200 layers, and most preferably 4-100 layers.

[0044] In a preferred embodiment of the present invention, the polypropylene composition A contained in each of the stacked polypropylene fabric layers may be the same or different, and the polypropylene fabric A contained in each layer may be selected independently. Preferably, the polypropylene composition A in each layer is the same.

[0045] According to the present invention, the polypropylene composite material has at least one of the following characteristics:

[0046] Longitudinal (MD) tensile strength ≥150 MPa, preferably ≥170 MPa; interlaminar peel strength ≥1.1 N / mm, preferably ≥1.3 N / mm. When the composite material is made of 24 layers of polypropylene fabric hot-pressed together with a thickness of about 1.8 mm, the drop hammer impact strength ≥240 J, preferably ≥250 J.

[0047] In this invention, tensile strength is determined according to the method specified in GB / T1040.1-2018, and interlaminar peel strength is determined according to the method specified in GB / T2358-98. The samples corresponding to the above two tests are the standard samples required in the above-mentioned testing standards.

[0048] In this invention, the drop hammer impact strength is determined according to the method specified in GB / T14153-1993, and the thickness of the sample is the thickness of the prepared product.

[0049] The fifth objective of this invention is to provide a method for preparing a polypropylene composite material, which includes the following steps: hot-pressing and fusing the polypropylene composite sheet and / or the polypropylene fabric together, and then cooling and shaping them to form a polypropylene composite material.

[0050] The preparation conditions of the present invention have a wide range of selection. In a preferred embodiment of the present invention, the hot pressing fusion temperature is 115-170°C, preferably 115-159°C, and more preferably 140-159°C.

[0051] In a preferred embodiment of the present invention, the pressure of the hot-pressing fusion is 2-10 MPa. In a preferred embodiment of the present invention, the preheating time of the hot-pressing fusion is 5-600 s, and the hot-pressing time is 1-600 s, preferably 10-500 s.

[0052] In a preferred embodiment of the present invention, the cooling and shaping pressure is 2-8 MPa, and the cooling and shaping time is 30s-700s.

[0053] In a more preferred embodiment of the present invention, the method for preparing the polypropylene composite material includes the following steps:

[0054] Step a: Polypropylene composition A, polypropylene composition B, and polypropylene composition C are co-extruded according to the CBABC structure and then cast or calendered to obtain polypropylene co-extruded sheets; preferably, the extrusion casting or calendering temperature is 200-230℃, and the temperature of the calendering roll is 50-70℃.

[0055] Step b: The polypropylene co-extruded sheet is stretched at a certain temperature to obtain a polypropylene stretched sheet. The stretching temperature is preferably 90-165℃, more preferably 90-140℃, and even more preferably 90-119℃ with a stretching ratio of 1-15 times.

[0056] Step c: Cut the polypropylene stretched sheet into polypropylene flat strips, and weave the flat strips into polypropylene fabric; preferably, the width of the polypropylene flat strip is 2-5 mm, and the polypropylene fabric includes plain weave, twill weave, satin weave, or other three-dimensional polypropylene fabrics.

[0057] Step d: The polypropylene sheets or fabrics are sequentially stacked and hot-pressed together, and then cooled and shaped to form a polypropylene composite material; the preferred hot-pressing conditions are: hot-pressing temperature 115-170℃, preferably 115-159℃, more preferably 140-159℃; hot-pressing pressure 2-10 MPa, preheating time 5-300s, hot-pressing time 1-300s, preferably 1-9s or 61-100s, cooling pressure 2-8 MPa, cooling time 30s-700s; the polypropylene fabrics in the polypropylene composite material can be placed at 0-90° between warp directions and / or the polypropylene composite sheets can be placed at 0-90° along their respective machine directions.

[0058] According to a preferred embodiment of the present invention, the pressure is preferably maintained continuously during the hot pressing and cooling process without any decrease. The hot pressing process is continuous, and preferably a continuous hot pressing composite material molding equipment is adopted, consisting of a preheating machine, a crawler-type continuous planar hot press, a crawler-type continuous planar cooling press, a sheet cutting machine, and a sheet stacking machine arranged in sequence. Preferably, the crawler-type continuous planar hot press has a preheating unit, an independent heating and pressurizing unit, an air cooling unit, and a lifting mechanism.

[0059] In the preparation process, the polypropylene sheets and / or polypropylene fabrics are sequentially stacked and preheated in a preheating machine. The preheated samples are then sequentially hot-pressed and fused using a tracked flatbed hot press, followed by cooling and shaping using a tracked continuous flatbed cooling press to produce a polypropylene composite material, i.e., a stacked hot-pressed product. Afterwards, the product is sliced ​​as needed using a sheet cutter, and then stacked and arranged using a sheet stacking machine. The hot-pressing temperature is controlled by the preheating unit, independent heating and pressurizing unit, and air-cooling unit in the tracked flatbed hot press, while the hot-pressing pressure is controlled by a lifting mechanism. According to the inventors' research, when the preparation process parameters are within the preferred range, and when the aforementioned preparation equipment is used to prepare the polymer composite material, the polymer composite material exhibits better tensile strength, impact performance, and interlaminar peel strength.

[0060] The sixth objective of this invention is to provide an application of the polypropylene composite sheet, polypropylene fabric, polypropylene composite material, and polypropylene composite material prepared by the preparation method described above in the fields of military materials, automobile manufacturing, sports protection, and consumer products.

[0061] According to specific embodiments of the present invention, the materials field includes the luggage and transportation industry, the footwear industry, the automobile manufacturing industry, the sports equipment manufacturing industry, the audio equipment manufacturing industry, and the military field.

[0062] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0063] (1) The polypropylene composite polymer of the present invention has good tensile strength, impact performance and interlaminar peel strength.

[0064] The polypropylene composite material has the following characteristics: longitudinal (MD) tensile strength ≥150 MPa, preferably ≥170 MPa; interlaminar peel strength ≥1.1 N / mm, preferably ≥1.3 N / mm; when the composite material is made of 24 layers of polypropylene fabric hot-pressed together with a thickness of about 1.8 mm, the drop hammer impact strength ≥240 J, preferably ≥250 J.

[0065] (2) The polypropylene composite material of the present invention is suitable for preparation at a lower hot pressing temperature and a wider hot pressing temperature range, which effectively reduces the energy consumption of equipment and the damage to the composite material caused by high temperature operation. At the same time, it still has good interlayer peel strength when prepared at a lower hot pressing temperature.

[0066] (3) This preparation method can reduce the hot pressing operation time, while improving production efficiency and reducing production energy consumption.

[0067] (4) The present invention reduces the hot pressing temperature and expands the hot pressing temperature range to 50°C; effectively reducing equipment energy consumption and damage to composite materials under high temperature operation. Detailed Implementation

[0068] The present invention will now be described in detail with reference to specific embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0069] In the following embodiments and comparative examples:

[0070] The extrusion calender and solid phase stretching equipment were purchased from Tianjin Hengrui Company, and the model is HRPC-800 multi-layer co-extrusion plastic stretching sheet production line.

[0071] (1) Melt mass flow rate (MFR): The test shall be performed in accordance with the method specified in GB / T 3682-2000, wherein the test temperature is 190℃ and the load is 2.16kg;

[0072] (2) Sheet tensile strength: determined according to the method specified in GB / T1040.1-2018;

[0073] (3) Drop hammer impact strength: determined according to the method specified in GB / T14153-1993;

[0074] (4) Interlayer peel strength: The test shall be performed in accordance with the method specified in QB / T2358-98.

[0075] In the following examples, the β-crystal nucleating agent with the brand name VP101B was sourced from the Beijing Research Institute of Chemical Industry, China Petroleum & Chemical Corporation; the sources of some raw materials are described in the examples, and the remaining raw materials are commercially available unless otherwise specified.

[0076] Example 1

[0077] This embodiment illustrates the preparation of the polypropylene composition, five-layer co-extruded polypropylene composite sheet, polypropylene fabric, and polypropylene composite material provided by the present invention.

[0078] (1) Preparation of polypropylene composition A:

[0079] Component a is a homopolymer polypropylene self-produced by the Beijing Research Institute of Chemical Industry, Sinopec, with a melting point of 160℃, a melt flow rate (melt mass flow rate) of 3.2 g / 10 min, and an isotacticity of 97%. Component b is a polypropylene impact copolymer self-produced by the Beijing Research Institute of Chemical Industry, Sinopec (with a cantilever beam impact strength of 23 KJ / m under 23℃ testing conditions). 2 The ethylene content is 11% wt, the melt flow rate is 2.0 g / 10 min, and the melting point is 155℃.

[0080] The components obtained above are weighed and mixed according to the specified proportions, wherein the mass fraction W of component a is... a The mass fraction W of component b is 80 parts by weight. b 20 parts by weight. Add 0.05 parts by weight of β-crystal nucleating agent of grade VP101B. Then, add the mixture to a high-speed mixer and mix thoroughly. Next, add the mixed material to the feeder of a twin-screw extruder manufactured by W&P. The material enters the twin screws through the feeder. During processing, the screw temperature is maintained between 200-230℃. After being melted and mixed evenly by the screws, extruded, granulated, and dried, polypropylene composition granules are obtained. The melt flow rate is measured to be 4.6 g / 10 min; the melting point of polypropylene composition A is 157℃.

[0081] (2) Preparation of polypropylene composition B:

[0082] Component α is a polyolefin elastomer of grade 6102, purchased from ExxonMobil, and is an ethylene-propylene copolymer; the ethylene content is 16% wt (melt flow rate at 190℃ and 2.16 kg load is 1.4 g / 10 min); component β is a random copolymer polypropylene of grade 6102, self-produced by Sinopec Beijing Research Institute of Chemical Industry, and is an ethylene-propylene-butene terpolymer with a melting point of 140℃ and a melt flow rate of 6.6 g / 10 min; component γ is a homopolymer polypropylene of grade 6102, self-produced by Sinopec Beijing Research Institute of Chemical Industry, with a melt flow rate of 3.2 g / 10 min, a melting point of 160℃, and an isotacticity of 97%. The mass fraction W of component α is... α The content is 45 parts by weight, and the mass fraction W of component β is... β For 45 parts by weight, W γ The mixture is 10 parts by weight. Then, the mixture is added to a high-speed mixer and mixed evenly. The mixed material is then added to the feeder of a twin-screw extruder manufactured by W&P. The material enters the twin screw through the feeder. During the processing, the screw temperature is maintained between 200-230℃. After being melted and mixed evenly by the screw, extruded, granulated and dried, polypropylene composition B granules are obtained. The melt mass flow rate is tested to be 6.9 g / 10 min, and the melting point of polypropylene composition B is 145℃.

[0083] (3) Preparation of polypropylene composition C:

[0084] Component x is a random copolymer polypropylene produced by the Beijing Research Institute of Chemical Industry of Sinopec. It is an ethylene-propylene-butene terpolymer with a melting point of 140℃ and a melt flow rate of 6.6 g / 10 min. Component y is a polyolefin elastomer of grade 6102, purchased from Exxon, which is an ethylene-propylene copolymer with an ethylene content of 16% wt (melt flow rate of 1.4 g / 10 min at 190℃ and 2.16 kg load).

[0085] The components obtained above are weighed and mixed according to the specified proportions, wherein the mass fraction W of component x is... x The mass fraction W of component y is 85 parts by weight. y The weight is 15 parts, and the other steps are the same as in step (1). Finally, polypropylene composition C granules are obtained. The melt mass flow rate is tested to be 5.2 g / 10 min. The melting point of polypropylene composition C is 138℃.

[0086] (4) Preparation of five-layer co-extruded polypropylene composite sheet:

[0087] The polypropylene composition A, polypropylene composition B, and polymer C granules obtained in steps (1) and (2) above are dried. Then, polypropylene composition A is added to the core extruder of a multi-layer extrusion calender, polypropylene composition B is added to the intermediate extruder of a multi-layer extrusion casting machine, and polypropylene composition C is added to the upper and lower surface extruders of a multi-layer extrusion casting machine. After the granules are co-extruded through the extruder die, they pass sequentially through calendering rollers and traction rollers, and then undergo solid-phase stretching, edge trimming, and winding to obtain the sheet material. The extrusion casting temperature is 230°C, and the calendering roller temperature is 60°C. The solid-phase stretching process is carried out at a temperature of 138°C, a stretching rate of 2 m / min, and a stretching ratio of 7 times.

[0088] After stretching and winding, a polypropylene composite sheet (composite film) is produced, which consists of an upper surface layer (film layer C), an intermediate layer (film layer B), a core layer (film layer A), an intermediate layer (film layer B), and a lower surface layer (film layer C). The thickness of the polypropylene composite sheet is 80 μm, where the thickness of film layer A accounts for 80% of the total sheet thickness, the thickness of film layer B accounts for 10% of the total sheet thickness, and the thickness of film layer C accounts for 10% of the total sheet thickness.

[0089] (5) Preparation of polypropylene fabric:

[0090] The five-layer co-extruded polypropylene composite sheet obtained in step (4) above is cut with a high-speed slitting machine with multiple blades to obtain an oriented polypropylene flat strip with a width of 3mm; the oriented flat strip is woven with a commercial weaving machine according to the designed fabric structure to obtain a plain weave polypropylene fabric.

[0091] (6) Preparation of polypropylene composite materials:

[0092] The polypropylene fabrics obtained in step (5) are sequentially stacked and hot-pressed to form a laminated polypropylene composite sheet. The laminated polypropylene composite sheet includes 24 layers of polypropylene fabric, with the polypropylene fabrics placed at a 90° angle between the warp and weft directions. The hot-pressing conditions are as follows: temperature 153℃, hot-pressing pressure 5 MPa, preheating time 300s, hot-pressing time 180s, and cooling time 600s.

[0093] The thickness of the prepared polypropylene composite material is 1.82 mm.

[0094] Example 2

[0095] This embodiment illustrates the preparation of the polypropylene composition, five-layer co-extruded polypropylene composite sheet, polypropylene fabric, and polypropylene composite material provided by the present invention.

[0096] (1) Preparation of polypropylene composition A:

[0097] Component a is a homopolymer polypropylene self-produced by the Beijing Research Institute of Chemical Industry of Sinopec, with a melting point of 165℃, a melt flow rate of 8.1 g / 10 min, and an isotacticity of 97%; component b is a polypropylene impact copolymer self-produced by the Beijing Research Institute of Chemical Industry of Sinopec, with a cantilever beam impact strength of 25 KJ / m under a test condition of 23℃. 2 The ethylene content is 8% wt, the melt flow rate is 3.2 g / 10 min, and the melting point is 155 °C. The components obtained above are weighed and mixed according to the specified proportions, wherein component a has a mass fraction W. a The mass fraction W of component b is 70 parts by weight. b The sample consisted of 30 parts by weight. 0.05 parts by weight of β-crystal nucleating agent (VP101B) was added. The mixture was then added to a high-speed mixer and mixed thoroughly. The mixed material was then fed into the feeder of a twin-screw extruder manufactured by W&P. The material entered the twin screws via the feeder. During processing, the screw temperature was maintained between 200-230°C. After being melted and mixed evenly by the screws, extruded, granulated, and dried, polypropylene composition granules were obtained. The melt flow rate was measured to be 7.3 g / 10 min. The melting point of polypropylene composition A was 161°C.

[0098] (2) Preparation of polypropylene composition B:

[0099] Component α is a polyolefin elastomer produced by Sinopec Beijing Research Institute of Chemical Industry, which is an ethylene-propylene copolymer with an ethylene content of 15% wt and a melting point of 105℃ (melt flow rate of 9 g / 10 min at 190℃ and 2.16 kg load); component β is a random copolymer polypropylene produced by Sinopec Beijing Research Institute of Chemical Industry, which is an ethylene-propylene-butene terpolymer with a melting point of 134℃ and a melt flow rate of 5.2 g / 10 min; component γ is a homopolymer polypropylene produced by Sinopec Beijing Research Institute of Chemical Industry, with a melting point of 165℃, a melt flow rate of 8.1 g / 10 min, and an isotacticity of 97%. The mass fraction W of component α is... α The mass fraction W of component β is 55 parts by weight. β For 40 parts by weight, W γ Five parts by weight were then added to a high-speed mixer and mixed evenly. The mixed material was then added to the feeder of a twin-screw extruder manufactured by W&P. The material entered the twin screws through the feeder. During the processing, the screw temperature was maintained between 200-230°C. After being melted and mixed evenly by the screws, extruded, granulated and dried, polypropylene composition B granules were obtained. The melt mass flow rate was tested to be 7.8 g / 10 min, and the melting point of polypropylene composition B was 156°C.

[0100] (3) Preparation of polypropylene composition C:

[0101] Component x is a random copolymer polypropylene, self-produced by the Beijing Research Institute of Chemical Industry of Sinopec, which is an ethylene-propylene-butene terpolymer with a melting point of 134℃ and a melt flow rate of 5.2 g / 10 min; component y and component α are polyolefin elastomers, also self-produced by the Beijing Research Institute of Chemical Industry of Sinopec, which is an ethylene-propylene copolymer with an ethylene content of 15% wt and a melting point of 105℃ (melt flow rate of 9 g / 10 min at 190℃ and 2.16 kg load). The components prepared above were weighed and mixed according to the specified proportions, wherein the mass fraction W of component x is... x The mass fraction W of component y is 80 parts by weight. y The weight is 20 parts, and the other steps are the same as in step (1). Finally, polypropylene composition C granules are obtained. The melt mass flow rate is 9.6 g / 10 min and the melting point of polypropylene composition C is 130 °C.

[0102] (4) Preparation of five-layer co-extruded polypropylene composite sheet:

[0103] The preparation process is the same as step (4) of Example 1.

[0104] (5) Preparation of polypropylene fabric:

[0105] The preparation process is the same as step (5) in Example 1.

[0106] (6) Preparation of polypropylene composite materials:

[0107] The preparation process is the same as step (6) in Example 1.

[0108] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0109] Example 3

[0110] This embodiment illustrates the preparation of the polypropylene composition, five-layer co-extruded polypropylene composite sheet, polypropylene fabric, and polypropylene composite material provided by the present invention.

[0111] (1) Preparation of polypropylene composition A:

[0112] Same as Example 1, wherein component a (Wa) has 90 parts by weight and component b (Wb) has 10 parts by weight. 0.05 parts by weight of β-crystal nucleating agent (VP101B) were added. Polypropylene composition A granules were obtained, and its melt flow rate was measured to be 6.8 g / 10 min. The melting point of polypropylene composition A is 158°C.

[0113] (2) Preparation of polypropylene composition B:

[0114] Same as in Example 1, wherein the mass fraction W of component α α The mass fraction W of component β is 35 parts by weight. β For 55 parts by weight, W γ Ten parts by weight were used to obtain polypropylene composition B granules. The melt flow rate was measured to be 7.3 g / 10 min, and the melting point of polypropylene composition B was 142 °C.

[0115] (3) Preparation of polypropylene composition C:

[0116] Same as in Example 1, wherein the mass fraction W of component x x The mass fraction W of component y is 90 parts by weight. y Ten parts by weight were used to obtain polypropylene composition C granules. The melt flow rate was measured to be 8.7 g / 10 min, and the melting point of polypropylene composition C was 139 °C.

[0117] (4) Preparation of five-layer co-extruded polypropylene composite sheet:

[0118] The preparation process is the same as step (4) of Example 1.

[0119] (5) Preparation of polypropylene fabric:

[0120] The preparation process is the same as step (5) in Example 1.

[0121] (6) Preparation of polypropylene composite materials:

[0122] The preparation process is the same as step (6) in Example 1.

[0123] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0124] Example 4

[0125] This embodiment illustrates the preparation of the polypropylene composition, five-layer co-extruded polypropylene composite sheet, polypropylene fabric, and polypropylene composite material provided by the present invention.

[0126] (1) Preparation of polypropylene composition A:

[0127] The preparation process is the same as step (1) in Example 1.

[0128] (2) Preparation of polypropylene composition B:

[0129] The preparation process is the same as step (2) of Example 1.

[0130] (3) Preparation of polypropylene composition C:

[0131] The preparation process is the same as step (3) in Example 1.

[0132] (4) Preparation of five-layer co-extruded polypropylene composite sheet:

[0133] The main steps are the same as in Example 1, wherein the thickness of film layer A accounts for 90% of the total thickness of the sheet, the thickness of film B accounts for 5% of the total thickness of the sheet, and the thickness of film C accounts for 5% of the total thickness of the sheet.

[0134] (5) Preparation of polypropylene fabric:

[0135] The preparation process is the same as step (5) in Example 1.

[0136] (6) Preparation of polypropylene composite materials:

[0137] The preparation process is the same as step (6) in Example 1.

[0138] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0139] Example 5

[0140] This embodiment illustrates the preparation of the polypropylene composition, five-layer co-extruded polypropylene composite sheet, polypropylene fabric, and polypropylene composite material provided by the present invention.

[0141] (1) Preparation of polypropylene composition A:

[0142] The preparation process is the same as step (1) in Example 1.

[0143] (2) Preparation of polypropylene composition B:

[0144] The preparation process is the same as step (2) of Example 1.

[0145] (3) Preparation of polypropylene composition C:

[0146] The preparation process is the same as step (3) in Example 1.

[0147] (4) Preparation of five-layer co-extruded polypropylene composite sheet:

[0148] The main steps are the same as in Example 1. The thickness of the polypropylene composite sheet is 80 μm, wherein the thickness of film layer A accounts for 70% of the total thickness of the sheet, the thickness of film B accounts for 15% of the total thickness of the sheet, and the thickness of film C accounts for 15% of the total thickness of the sheet.

[0149] (5) Preparation of polypropylene fabric:

[0150] The preparation process is the same as step (5) in Example 1.

[0151] (6) Preparation of polypropylene composite materials:

[0152] The preparation process is the same as step (6) in Example 1.

[0153] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0154] Example 6

[0155] This embodiment illustrates the preparation of the polypropylene composition, five-layer co-extruded polypropylene composite sheet, polypropylene fabric, and polypropylene composite material provided by the present invention.

[0156] (1) Preparation of polypropylene composition A:

[0157] The preparation process is the same as step (1) in Example 1.

[0158] (2) Preparation of polypropylene composition B:

[0159] The preparation process is the same as step (2) of Example 1.

[0160] (3) Preparation of polypropylene composition C:

[0161] The preparation process is the same as step (3) in Example 1.

[0162] (4) Preparation of five-layer co-extruded polypropylene composite sheet:

[0163] The preparation process is the same as step (4) of Example 1.

[0164] (5) Preparation of polypropylene fabric:

[0165] The main steps are the same as step (5) in Example 1. The oriented flat strip is woven into a satin polypropylene fabric by using a commercial weaving machine according to the designed fabric structure.

[0166] (6) Preparation of polypropylene composite materials:

[0167] The preparation process is the same as step (6) in Example 1.

[0168] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0169] Example 7

[0170] This embodiment illustrates the preparation of the polypropylene composition, five-layer co-extruded polypropylene composite sheet, polypropylene fabric, and polypropylene composite material provided by the present invention.

[0171] (1) Preparation of polypropylene composition A:

[0172] The preparation process is the same as step (1) in Example 1.

[0173] (2) Preparation of polypropylene composition B:

[0174] The preparation process is the same as step (2) of Example 1.

[0175] (3) Preparation of polypropylene composition C:

[0176] The preparation process is the same as step (3) in Example 1.

[0177] (4) Preparation of five-layer co-extruded polypropylene composite sheet:

[0178] The main preparation process is the same as step (4) in Example 1. The sheet stretching ratio is 10 times.

[0179] (5) Preparation of polypropylene fabric:

[0180] The preparation process is the same as step (5) in Example 1.

[0181] (6) Preparation of polypropylene composite materials:

[0182] The preparation process is the same as step (6) in Example 1.

[0183] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0184] Example 8

[0185] This embodiment illustrates the preparation of the polypropylene composition, five-layer co-extruded polypropylene composite sheet, polypropylene fabric, and polypropylene composite material provided by the present invention.

[0186] (1) Preparation of polypropylene composition A:

[0187] The preparation process is the same as step (1) in Example 1.

[0188] (2) Preparation of polypropylene composition B:

[0189] The preparation process is the same as step (2) of Example 1.

[0190] (3) Preparation of polypropylene composition C:

[0191] The preparation process is the same as step (3) in Example 1.

[0192] (4) Preparation of five-layer co-extruded polypropylene composite sheet:

[0193] The preparation process is the same as step (4) of Example 1.

[0194] (5) Preparation of polypropylene fabric:

[0195] The preparation process is the same as step (5) in Example 1.

[0196] (6) Preparation of polypropylene composite materials:

[0197] The main preparation process is the same as step (6) in Example 1. The polypropylene fabric is placed at a 45° angle between the warp and weft directions.

[0198] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0199] Example 9

[0200] This embodiment illustrates the preparation of the polypropylene composition, five-layer co-extruded polypropylene composite sheet, polypropylene fabric, and polypropylene composite material provided by the present invention.

[0201] (1) Preparation of polypropylene composition A:

[0202] The preparation process is the same as step (1) in Example 1.

[0203] (2) Preparation of polypropylene composition B:

[0204] The preparation process is the same as step (2) of Example 1.

[0205] (3) Preparation of polypropylene composition C:

[0206] The preparation process is the same as step (3) in Example 1.

[0207] (4) Preparation of five-layer co-extruded polypropylene composite sheet:

[0208] The preparation process is the same as step (4) of Example 1.

[0209] (5) Preparation of polypropylene fabric:

[0210] The preparation process is the same as step (5) in Example 1.

[0211] (6) Preparation of polypropylene composite materials:

[0212] The main preparation process is the same as step (6) in Example 1. The polypropylene fabric is placed with the warp direction at 0° to the warp direction.

[0213] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0214] Example 10

[0215] This embodiment illustrates the preparation of the polypropylene composition, five-layer co-extruded polypropylene composite sheet, polypropylene fabric, and polypropylene composite material provided by the present invention.

[0216] (1) Preparation of polypropylene composition A:

[0217] The preparation process is the same as step (1) in Example 1.

[0218] (2) Preparation of polypropylene composition B:

[0219] The preparation process is the same as step (2) of Example 1.

[0220] (3) Preparation of polypropylene composition C:

[0221] The preparation process is the same as step (3) in Example 1.

[0222] (4) Preparation of five-layer co-extruded polypropylene composite sheet:

[0223] The preparation process is the same as step (4) of Example 1.

[0224] (5) Preparation of polypropylene fabric:

[0225] The preparation process is the same as step (5) in Example 1.

[0226] (6) Preparation of polypropylene composite materials:

[0227] The main preparation process is the same as step (6) in Example 1. The laminated polypropylene composite sheet includes two layers of polypropylene fabric. The hot-pressing conditions used are: temperature 145℃, hot-pressing pressure 2MPa, preheating time 150s, hot-pressing time 60s, and cooling time 300s. The thickness of the prepared polypropylene composite material is 136μm.

[0228] Example 11

[0229] This embodiment illustrates the preparation of the polypropylene composition, five-layer co-extruded polypropylene composite sheet, polypropylene fabric, and polypropylene composite material provided by the present invention.

[0230] (1) Preparation of polypropylene composition A:

[0231] The preparation process is the same as step (1) in Example 1.

[0232] (2) Preparation of polypropylene composition B:

[0233] The preparation process is the same as step (2) of Example 1.

[0234] (3) Preparation of polypropylene composition C:

[0235] The preparation process is the same as step (3) in Example 1.

[0236] (4) Preparation of five-layer co-extruded polypropylene composite sheet:

[0237] The preparation process is the same as step (4) of Example 1.

[0238] (5) Preparation of polypropylene fabric:

[0239] The preparation process is the same as step (5) in Example 1.

[0240] (6) Preparation of polypropylene composite materials:

[0241] The main preparation process is the same as step (6) in Example 1. The laminated polypropylene composite sheet includes 100 layers of polypropylene fabric. The hot-pressing conditions used are: 159°C, hot-pressing pressure of 10 MPa, preheating time of 420 s, hot-pressing time of 300 s, and cooling time of 700 s. The thickness of the prepared polypropylene composite material is 7.45 mm.

[0242] Example 12

[0243] This embodiment illustrates the preparation of the polypropylene composition, five-layer co-extruded polypropylene composite sheet, polypropylene fabric, and polypropylene composite material provided by the present invention.

[0244] (1) Preparation of polypropylene composition A:

[0245] The preparation process is the same as step (1) in Example 1.

[0246] (2) Preparation of polypropylene composition B:

[0247] The preparation process is the same as step (2) of Example 1.

[0248] (3) Preparation of polypropylene composition C:

[0249] The preparation process is the same as step (3) in Example 1.

[0250] (4) Preparation of five-layer co-extruded polypropylene composite sheet:

[0251] The preparation process is the same as step (4) of Example 1.

[0252] (5) Preparation of polypropylene fabric:

[0253] The preparation process is the same as step (5) in Example 1.

[0254] (6) Preparation of polypropylene composite materials:

[0255] The main preparation process is the same as step (6) in Example 1. The temperature is 155℃, the hot pressing pressure is 8 MPa, the preheating time is 300s, the hot pressing time is 300s, and the cooling time is 700s. The thickness of the prepared polypropylene composite material is 1.61mm.

[0256] Example 13

[0257] This embodiment illustrates the preparation of the polypropylene composition, five-layer co-extruded polypropylene sheet, polypropylene fabric, and polypropylene composite material provided by the present invention.

[0258] (1) Preparation of polypropylene composition A:

[0259] The preparation process is the same as step (1) in Example 1.

[0260] (2) Preparation of polypropylene composition B:

[0261] The preparation process is the same as step (2) of Example 1.

[0262] (3) Preparation of polypropylene composition C:

[0263] The preparation process is the same as step (3) in Example 1.

[0264] (4) Preparation of five-layer co-extruded polypropylene composite sheet:

[0265] The preparation process is the same as step (4) of Example 1.

[0266] (5) Preparation of polypropylene composite materials:

[0267] The main preparation process is the same as step (6) of Example 1. The difference is that the polypropylene fabric is not prepared, and the five-layer co-extruded polypropylene sheet obtained in step (4) above is used instead of the polypropylene fabric in Example 1, and then stacked and hot-pressed.

[0268] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0269] Comparative Example 1

[0270] Five-layer co-extruded polypropylene composite sheets were prepared according to the method of Example 1. However, only polypropylene composition A was used for extrusion casting into a single-layer film with a thickness of 80 μm. Polypropylene fabrics and polypropylene composite materials were also prepared according to the method of Example 1.

[0271] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0272] Comparative Example 2

[0273] Five-layer co-extruded polypropylene composite sheets were prepared according to the method of Example 1. However, only polypropylene composition B was used for extrusion casting into a single-layer film with a thickness of 80 μm. Polypropylene fabrics and polypropylene composite materials were also prepared according to the method of Example 1.

[0274] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0275] Comparative Example 3

[0276] Five-layer co-extruded polypropylene composite sheets were prepared according to the method of Example 1. However, only polypropylene composition C was used for extrusion casting into a single-layer film with a thickness of 80 μm. Polypropylene fabrics and polypropylene composite materials were also prepared according to the method of Example 1.

[0277] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0278] Comparative Example 4

[0279] Five-layer co-extruded polypropylene composite sheets were prepared according to the method of Example 1. However, polypropylene composition A contained only component b. Polypropylene fabrics and polypropylene composite materials were also prepared according to the method of Example 1.

[0280] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0281] Comparative Example 5

[0282] Five-layer co-extruded polypropylene composite sheets were prepared according to the method of Example 1. However, the polypropylene composition C contained only component y. Polypropylene fabrics and polypropylene composite materials were also prepared according to the method of Example 1.

[0283] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0284] Comparative Example 6

[0285] A five-layer co-extruded polypropylene composite sheet was prepared according to the method of Example 1. The only difference was that the thickness of film layer A accounted for 95% of the total sheet thickness, the thickness of film B accounted for 2.5% of the total sheet thickness, and the thickness of film C accounted for 2.5% of the total sheet thickness. Polypropylene fabrics and polypropylene composite materials were also prepared according to the method of Example 1.

[0286] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0287] Comparative Example 7

[0288] A five-layer co-extruded polypropylene composite sheet was prepared according to the method of Example 1. The only difference was that the thickness of film layer A accounted for 50% of the total sheet thickness, the thickness of film B accounted for 25% of the total sheet thickness, and the thickness of film C accounted for 25% of the total sheet thickness. Polypropylene fabrics and polypropylene composite materials were also prepared according to the method of Example 1.

[0289] The thickness of the prepared polypropylene composite material is similar to that of Example 1.

[0290] Experimental Example

[0291] The polypropylene composite materials obtained in the above examples and comparative examples were tested according to the following methods, and the test results are shown in Table 1.

[0292] (1) Tensile strength: Samples were prepared and tested according to the methods specified in GB / T1040.1-2018;

[0293] (2) Interlayer peel strength: Samples were prepared and measured in accordance with the method specified in QB / T2358-98.

[0294] (3) Drop hammer impact strength: The test was conducted according to the method specified in GB / T14153-1993. Among them, the thickness of the polypropylene composite materials obtained in Examples 1-9, Example 13, and Comparative Examples 1-7 were all similar, around 1.8 mm, and all within the range of 1.8 mm ± 1 mm.

[0295] Table 1

[0296]

[0297]

[0298] The results from the examples in Table 1 show that the polypropylene composite material prepared according to the present invention has both excellent tensile and impact resistance, as well as good interlaminar peel strength at relatively low hot-pressing temperatures. The longitudinal (MD) tensile strength of the polypropylene composite material of the present invention is ≥150 MPa, and the interlaminar peel strength is ≥1.1 N / mm. When the polypropylene composite material is obtained by hot-pressing 24 layers of polypropylene fabric with a thickness of approximately 1.8 mm, the drop hammer impact strength is ≥240 J.

[0299] As can be seen from preferred embodiments 1-3, the longitudinal (MD) tensile strength of the polypropylene composite material prepared by the present invention is ≥170 MPa, and the interlaminar peel strength is ≥1.3 N / mm; the polypropylene composite material is obtained by hot pressing 24 layers of polypropylene fabric, and when the thickness is about 1.8 mm, the drop hammer impact strength is ≥250 J. As can be seen from comparative examples 1-7, using only a single-layer film structure or using a film layer ratio outside the scope of the embodiments will lead to a decrease in the performance of the laminated polypropylene sheet or fabric, resulting in a significant decrease in the tensile strength, impact performance, or interlaminar peel strength of the obtained polypropylene composite material.

[0300] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

[0301] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

Claims

1. A polypropylene composite sheet, comprising a film layer A containing a polypropylene composition A, a film layer B containing a polypropylene composition B, and a film layer C containing a polypropylene composition C; the polypropylene composite sheet has a CBABC layer structure, with the film layer A as the center, and the film layer B and the film layer C located sequentially on both sides of the film layer A from the inside out; the film layers B on both sides of the film layer A may be the same or different, and the film layers C on both sides of the film layer A may be the same or different. in, Polypropylene composition A comprises homopolymer polypropylene a and impact copolymer polypropylene b; polypropylene composition B comprises random copolymer polypropylene β and homopolymer polypropylene γ; polypropylene composition C comprises random copolymer polypropylene x; polypropylene composition B and polypropylene composition C independently contain a heat-bonding enhancer; Based on the total thickness of the polypropylene composite sheet, the thickness of film layer A accounts for 51%-89% of the total thickness; the thickness of film layer B accounts for 6%-20% of the total thickness; and the thickness of film layer C accounts for 5%-30% of the total thickness. Based on the total weight of the polypropylene composition A, the polypropylene composition A comprises 50-99 wt% homopolymer polypropylene a and 1-50 wt% impact copolymer polypropylene b. Based on the total weight of the polypropylene composition B, the polypropylene composition B comprises 30-60 wt% of a heat-bonding reinforcing agent, 35-55 wt% of random copolymer polypropylene β and 5-15 wt% of homopolymer polypropylene γ. Based on the total weight of the polypropylene composition C, the polypropylene composition C comprises 70-99 wt% random copolymer polypropylene x and 1-30 wt% thermal bonding enhancer.

2. The polypropylene composite sheet according to claim 1, characterized in that: The polypropylene composition A comprises 70-90 wt% homopolymer polypropylene a and 10-30 wt% impact copolymer polypropylene b.

3. The polypropylene composite sheet according to claim 1, characterized in that: The polypropylene composition B comprises 35-55 wt% of a heat-bonding reinforcing agent, 40-55 wt% of random copolymer polypropylene β, and 5-10 wt% of homopolymer polypropylene γ.

4. The polypropylene composite sheet according to claim 1, characterized in that: The polypropylene composition C comprises 80-90 wt% random copolymer polypropylene x and 10-20 wt% heat-bonding enhancer.

5. The polypropylene composite sheet according to claim 1, characterized in that: Based on the total thickness of the polypropylene composite sheet, the thickness of film layer A accounts for 71%-89% of the total thickness; the thickness of film layer B accounts for 6%-15% of the total thickness; and the thickness of film layer C accounts for 5%-15% of the total thickness.

6. The polypropylene composite sheet according to claim 1, characterized in that: The homopolymer polypropylene a has a melting point of 160-170℃; and / or, The homopolymer polypropylene a has a melt flow rate of 0.5-50 g / 10 min at 190 °C and a load of 2.16 kg; and / or, The isotacticity (mm) of the homopolymer polypropylene a is not less than 96%.

7. The polypropylene composite sheet according to claim 1, characterized in that: The homopolymer polypropylene a has a melt flow rate of 1-20 g / 10 min at 190 °C and 2.16 kg load.

8. The polypropylene composite sheet according to claim 1, characterized in that: The homopolymer polypropylene a has a melt flow rate of 2.5-18 g / 10 min at 190 °C and 2.16 kg load.

9. The polypropylene composite sheet according to claim 1, characterized in that: The monomer for the copolymerization of the impact-resistant polypropylene b and propylene is ethylene or butene; and / or, The impact-resistant copolymer polypropylene b has a melting point of 150-170℃; and / or, The impact-resistant copolymer polypropylene b has a melt flow rate of 0.5-50 g / 10 min at 190°C and a load of 2.16 kg; and / or, The cantilever beam impact strength of the impact-resistant copolymer polypropylene b is not less than 20 KJ / m. 2 .

10. The polypropylene composite sheet according to claim 1, characterized in that: The monomer for the copolymerization of the impact-resistant polypropylene b and propylene is butene; and / or, The impact-resistant copolymer polypropylene b has a melt flow rate of 1-20 g / 10 min at 190°C and 2.16 kg load.

11. The polypropylene composite sheet according to claim 1, characterized in that: The impact-resistant copolymer polypropylene b has a melt flow rate of 2.5-18 g / 10 min at 190°C and 2.16 kg load.

12. The polypropylene composite sheet according to claim 1, characterized in that: The random copolymer polypropylene β has a melting point of 120-140℃; and / or, The random copolymer polypropylene β has a melt flow rate of 0.5-50 g / 10 min at 190 °C and 2.16 kg load.

13. The polypropylene composite sheet according to claim 1, characterized in that: The random copolymer polypropylene β has a melt flow rate of 1-20 g / 10 min at 190 °C and 2.16 kg load.

14. The polypropylene composite sheet according to claim 1, characterized in that: The random copolymer polypropylene β has a melt flow rate of 3-18 g / 10 min at 190 °C and 2.16 kg load.

15. The polypropylene composite sheet according to claim 1, characterized in that: The random copolymer polypropylene β is a copolymer of propylene with ethylene and / or butene.

16. The polypropylene composite sheet according to claim 1, characterized in that: The random copolymer polypropylene β is an ethylene-propylene-butene terpolymer and / or a propylene-ethylene binary copolymer.

17. The polypropylene composite sheet according to claim 1, characterized in that: The homopolymer polypropylene γ has a melting point of 160-170℃; and / or, The homopolymer polypropylene γ has a melt flow rate of 0.5-50 g / 10 min at 190 °C and a load of 2.16 kg; and / or, The isotacticity (mm) of the homopolymer polypropylene γ is not less than 96%.

18. The polypropylene composite sheet according to claim 1, characterized in that: The homopolymer polypropylene γ has a melt flow rate of 1-20 g / 10 min at 190 °C and 2.16 kg load.

19. The polypropylene composite sheet according to claim 1, characterized in that: The homopolymer polypropylene γ has a melt flow rate of 2.5-18 g / 10 min at 190 °C and 2.16 kg load.

20. The polypropylene composite sheet according to claim 1, characterized in that: The random copolymer polypropylene x has a melting point of 120-140℃; and / or, The random copolymer polypropylene x has a melt flow rate of 0.5-50 g / 10 min at 190 °C and 2.16 kg load; and / or, The random copolymer polypropylene x is a copolymer of propylene with ethylene and / or butene.

21. The polypropylene composite sheet according to claim 1, characterized in that: The random copolymer polypropylene x has a melt flow rate of 1-20 g / 10 min at 190 °C and 2.16 kg load; and / or, The random copolymer polypropylene x is an ethylene-propylene-butene terpolymer and / or a propylene-ethylene binary copolymer.

22. The polypropylene composite sheet according to claim 1, characterized in that: The random copolymer polypropylene x has a melt flow rate of 3-18 g / 10 min at 190 °C and 2.16 kg load.

23. The polypropylene composite sheet according to claim 1, characterized in that: The melting point or flow temperature of the thermal bonding enhancer is 70-110℃; and / or, The heat-bonding reinforcing agent has a melt flow rate of 0.5-50 g / 10 min at 190°C and a load of 2.16 kg; and / or, The heat-bonding reinforcing agent is selected from one or more of polyolefin elastomers, ethylene propylene diene monomer (EPDM) rubber, SEBS, SBS, EVA, and petroleum resins.

24. The polypropylene composite sheet according to claim 1, characterized in that: The melt flow rate of the heat-bonding reinforcing agent at 190°C and 2.16 kg load is 1-20 g / 10 min.

25. The polypropylene composite sheet according to claim 1, characterized in that: The melt flow rate of the heat-bonding reinforcing agent at 190°C and 2.16 kg load is 3-18 g / 10 min.

26. The polypropylene composite sheet according to claim 1, characterized in that: The heat-adhesive reinforcing agent is a polyolefin elastomer and / or petroleum resin.

27. The polypropylene composite sheet according to claim 26, characterized in that: The polyolefin elastomer is a copolymer elastomer of ethylene with propylene and / or α-olefins.

28. The polypropylene composite sheet according to claim 27, characterized in that: The polyolefin elastomer is a copolymer elastomer of ethylene and propylene and / or α-olefin; the α-olefin is a C4-C12 α-olefin.

29. The polypropylene composite sheet according to claim 28, characterized in that: The α-olefin is 1-butene and / or 1-octene.

30. The polypropylene composite sheet according to claim 26, characterized in that: The petroleum resin is a hydrogenated petroleum resin of C5 and / or C9.

31. The polypropylene composite sheet according to claim 26, characterized in that: The petroleum resin is a C5 and / or C9 hydrogenated petroleum resin with a softening point of 100-150℃.

32. The polypropylene composite sheet according to claim 26, characterized in that: The petroleum resin is a C5 and / or C9 hydrogenated petroleum resin with a softening point of 100-150℃; the petroleum resin is a cyclopentadiene type resin.

33. The polypropylene composite sheet according to claim 1, characterized in that: The polypropylene composition A also contains a β-crystal nucleating agent.

34. The polypropylene composite sheet according to claim 33, characterized in that: The β-crystal nucleating agent is selected from at least one of polycyclic aromatic hydrocarbons, group IIA binary complexes, aromatic diamides, rare earth compounds, and cyclic dicarboxylate nucleating agents; and / or, Based on a total amount of 100 parts by weight of the polypropylene composition A, the content of the β-crystal nucleating agent is 0.01-0.5 parts by weight.

35. The polypropylene composite sheet according to any one of claims 1-34, characterized in that: The melting point of polypropylene composition A is greater than that of polypropylene composition B and polypropylene composition C; and / or, The CBABC layered structure of the polypropylene composite sheet is obtained by co-extrusion of components including polypropylene composition A, polypropylene composition B and polypropylene composition C.

36. The polypropylene composite sheet according to any one of claims 1-34, characterized in that: The melting point of polypropylene composition A is greater than that of polypropylene composition B and polypropylene composition C; the melting point of homopolymer polypropylene a in polypropylene composition A is greater than that of random copolymer polypropylene β in polypropylene composition B and random copolymer polypropylene x in polypropylene composition C, and the corresponding melting point temperature difference is greater than or equal to 10°C.

37. A method for preparing a polypropylene composite sheet according to any one of claims 1-36, comprising co-extruding a component comprising polypropylene composition A, polypropylene composition B and polypropylene composition C.

38. The preparation method according to claim 37, characterized in that, Polypropylene composition A, polypropylene composition B, and polypropylene composition C are co-extruded, cast or calendered, and stretched according to a CBABC structure to obtain the polypropylene composite sheet.

39. The method for preparing the polypropylene composite sheet according to claim 38, characterized in that, The preparation of the polypropylene composition A includes melt blending of components including the homopolymer polypropylene a and the impact copolymer polypropylene b; and / or, The preparation of the polypropylene composition B includes melt blending of components including the thermal bonding enhancer, random copolymer polypropylene β, and homopolymer polypropylene γ; and / or, The preparation of the polypropylene composition C includes melt blending of the random copolymer polypropylene x and the thermal bonding enhancer; and / or, The temperatures for co-extrusion and casting are each independently selected from 200-240°C; and / or, The temperature of the calender rolls is 50-70℃; and / or, The stretching conditions include: a stretching temperature of 90-165℃; and a stretching ratio of 1-15 times.

40. The method for preparing polypropylene composite sheet according to claim 38, characterized in that, The stretching conditions include: a stretching temperature of 90-140℃ and a stretching ratio of 1-15 times.

41. The method for preparing polypropylene composite sheets according to claim 38, characterized in that, The stretching conditions include: a stretching temperature of 90-119℃ and a stretching ratio of 1-15 times.

42. A polypropylene fabric, a three-dimensional polypropylene fabric obtained by weaving a polypropylene composite sheet according to any one of claims 1-36.

43. The polypropylene fabric according to claim 42, characterized in that: The polypropylene fabric is obtained by slitting and weaving the polypropylene composite sheet; and / or, the polypropylene fabric has a three-dimensional structure of plain weave, twill weave and / or satin weave.

44. A polypropylene composite material, said polypropylene composite material being prepared by hot pressing together multiple layers of polypropylene composite sheets as described in any one of claims 1-35 and / or polypropylene fabrics as described in claims 42 or 43.

45. The polypropylene composite material according to claim 44, characterized in that, The polypropylene composite material is prepared by hot pressing multiple layers of the polypropylene composite sheet or the polypropylene fabric; and / or The multilayer polypropylene fabric is stacked from top to bottom with warp directions arranged at 0-90° intervals; and / or, The multilayer polypropylene sheets are stacked from top to bottom at an angle of 0-90° along their respective machine directions; and / or, The multilayer polypropylene sheet and / or multilayer polypropylene fabric has two or more layers.

46. ​​The polypropylene composite material according to claim 45, characterized in that, The number of layers in the multilayer polypropylene sheet and / or multilayer polypropylene fabric is 2-200.

47. The polypropylene composite material according to claim 45, characterized in that, The number of layers in the multilayer polypropylene sheet and / or multilayer polypropylene fabric is 4-100.

48. A method for preparing the polypropylene composite material according to any one of claims 44-47, the method comprising the following steps: The polypropylene composite sheet and / or the polypropylene fabric are laminated and fused together by hot pressing, and then cooled and shaped to form a polypropylene composite material.

49. The preparation method according to claim 48, characterized in that: The hot-pressing fusion temperature is 115-170℃; and / or, The pressure for the hot-pressing fusion is 2-10 MPa; and / or, The preheating time for the hot-pressing fusion is 5-600s, and the hot-pressing time is 1-600s; and / or, The cooling and shaping pressure is 2-8 MPa, and the cooling and shaping time is 30-700 seconds.

50. The preparation method according to claim 48, characterized in that: The hot-pressing fusion temperature is 115-159℃; and / or, The preheating time for hot-pressing fusion is 5-600s, and the hot-pressing time is 10-500s.

51. The preparation method according to claim 48, characterized in that: The temperature for hot pressing and fusion is 140-159℃.

52. The application of the polypropylene composite sheet according to any one of claims 1-36, the polypropylene fabric according to claim 42 or 43, the polypropylene composite material according to any one of claims 44-47, and the polypropylene composite material prepared by the preparation method according to any one of claims 48-51 in the fields of military materials and consumer products.

53. The application according to claim 52, characterized in that: The applications are in the fields of automobile manufacturing and sports protection.

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