COMPOSITE STRUCTURED LAMINATE

Abstract

A composite laminate includes a first layer of a fabric material, a second layer of the fabric material, and an internal layer disposed between the first layer of the fabric material and the second layer of the fabric material. The internal layer includes a polymer mixture with one or more polymers, graphene, and a binder and a plurality of fibers dispersed in the polymer mixture.

Claims

1. A composite laminate, comprising: a first layer of a fabric material; a second layer of the fabric material; and an internal layer disposed between the first layer of the fabric material and the second layer of the fabric material, wherein the internal layer comprises: a polymer mixture comprising one or more polymers, graphene, and a binder; and a plurality of fibers randomly dispersed in the polymer mixture.

2. The composite laminate of claim 1, wherein the graphene comprises a plurality of graphene nanoplatelets.

3. The composite laminate of claim 1, wherein the one or more polymers has a melt flow rate (MFR) in a range from ten to sixty.

4. The composite laminate of claim 1, wherein the one or more polymers is polypropylene.

5. The composite laminate of claim 1, wherein the polymer mixture has a relative composition by weight of at least 90% of the polymer, at least 1% of the graphene, and at least 1% of the binder.

6. The composite laminate of claim 1, wherein the polymer mixture further comprises a UV protectant.

7. The composite laminate of claim 6, wherein the polymer mixture has a relative composition by weight of at least 90% of the polymer, at least 1% of the graphene, at least 1% of the binder, and at least 0.15% of the UV protectant.

8. The composite laminate of claim 1, wherein the composite laminate has a tensile strength of at least 12,000 psi.

9. The composite laminate of claim 1, wherein the composite laminate has a stiffness range of approximately 800,000 to 1,000,000 psi.

10. The composite laminate of claim 1, wherein the plurality of fibers comprises fiberglass pieces randomly distributed within the polymer mixture.

11. An internal layer for use in a laminate, the internal layer comprising: a polymer mixture comprising one or more polymers, graphene, and a binder; and a plurality of fibers randomly dispersed in the polymer mixture.

12. The internal layer of claim 11, wherein the graphene comprises a plurality of graphene nanoplatelets.

13. The internal layer of claim 11, wherein the one or more polymers has a melt flow rate (MFR) in a range from ten to sixty.

14. The internal layer of claim 11, wherein the one or more polymers is polypropylene.

15. The internal layer of claim 11, wherein the polymer mixture has a relative composition by weight of at least 90% of the polymer, at least 1% of the graphene, and at least 1% of the binder.

16. The internal layer of claim 11, wherein the polymer mixture further comprises a UV protectant.

17. The internal layer of claim 16, wherein the polymer mixture has a relative composition by weight of at least 90% of the polymer, at least 1% of the graphene, at least 1% of the binder, and at least 0.15% of the UV protectant.

18. The internal layer of claim 11, wherein the laminate has a tensile strength of at least 12,000 psi.

19. The internal layer of claim 11, wherein the laminate has a stiffness range of approximately 800,000 to 1,000,000 psi.

20. The internal layer of claim 11, wherein the plurality of fibers comprises fiberglass pieces disposed at randomly distributed angles within the polymer mixture.

Description

BRIEF DESCRIPTION OF FIGURES

[0014] The following figures are included to illustrate certain aspects of the present disclosure, and should not be viewed as exclusive embodiments. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to one having ordinary skill in the art and the benefit of this disclosure.

[0015] FIG. 1 is a table depicting the properties of a scrim for use in accordance with certain embodiments of the present disclosure;

[0016] FIG. 2 is a table depicting the properties of fiberglass roving for use in accordance with certain embodiments of the present disclosure;

[0017] FIG. 3 is a diagrammatic elevated side view of one embodiment of a laminate production apparatus in accordance with the present disclosure;

[0018] FIG. 4 is a diagrammatic elevated side view of another embodiment of a laminate production apparatus in accordance with the present disclosure;

[0019] FIG. 5 is a diagram illustrating an example laminate and its structure in accordance with the present disclosure;

[0020] FIG. 6A is a diagram illustrating a top-down view showing fiber orientation of an example laminate in accordance with the present disclosure; and

[0021] FIG. 6B is a diagram illustrating a view of an angled fiber in the example laminate of FIG. 6A.

DETAILED DESCRIPTION

[0022] It should be understood at the outset that, although example implementations of embodiments of the disclosure are illustrated below, the present disclosure may be implemented using any number of techniques, whether currently known or not. The present disclosure should in no way be limited to the example implementations, drawings, and techniques illustrated below. Additionally, the drawings are not necessarily drawn to scale.

[0023] The present disclosure relates generally to the composition and the production of a composite structural laminate.

[0024] In certain embodiments, a composite structural laminate comprises scrim (e.g., scrim layers 502a,b of FIG. 5), a compounded polymer mixture (e.g., polymer mixture 506 of FIG. 5), and fill material (e.g., fibers 508 of FIG. 5). The scrim serves as a lightweight fabric used on the outside of the laminate to improve adhesion to, for example, adhesives, paint, and coatings. An exemplary scrim may be composed of polyester (such as the polyester scrim set out in FIG. 1), nylon, polyethylene, or any other material conventionally known in the art. The compounded polymer mixture comprises a polymer component, a graphene component, and a multicompatible binder. The fill material may be some form of fiber conventionally known in the art including fiberglass roving, sisal roving, or several varieties of hemp. An exemplary fill material in the form of fiber rovings may have the properties set out in FIG. 2. The composite structural laminate may be formed from a first and second outer scrim layer adhered, or otherwise coupled, to one another having the compounded polymer mixture and fill material disposed therebetween.

[0025] In some embodiments, the compounded polymer mixture may further comprise an ultraviolet (UV) radiation protection component, which may be any material known in the art for reducing the impact of exposure to UV radiation. In such embodiments, the relative proportion of the described components may be substantially: 96.35% polypropylene component, 1.0-5% graphene component, 1.5-3% multicompatible binder, and 0.15-0.5% UV radiation protection component.

[0026] For certain embodiments, the polymer component may be polypropylene. This polypropylene may be purchased in any form conventionally known in the art. Polypropylene having a 10 to 60 Melt Flow Rate (MFR), such as PP1024E4 polypropylene from ExxonMobil. Similarly, the graphene component may include any size of graphene nanoplatelets. In some embodiments, the graphene component isXGS C-300 graphene nanoplatelets. The multicompatible binder may be any material or substance known in the art to promote adhesion of polymers to fiberglass. For example, in some embodiments, the multicompatible binder may be Priex 20097.

[0027] To create the compounded polymer mixture, the various constituents may be placed in a compounding vat. Within the compounding vat, the constituents may be agitated and heated until the contents of the compounding vat are substantially fluid. Once in this substantially fluid state, the mixed components may then be passed through an extruder to form pellets. The pellets may then be machined down or pulverized to 20 mesh particles.

[0028] One embodiment of a method of fabricating the composite structural laminate is depicted in FIG. 3. A first outer scrim layer, composed of ½-3 oz. scrim, is fed from a first scrim roller 20 onto conveyor belt 10. The first outer scrim layer may be between 8 ft-9 ft, 6 in. wide. A fiber chopper 30 is disposed above conveyor belt 10. Fiber roving 31 is fed into fiber chopper 30 which has a knife blade 32 arranged therein and configured to cut fiber roving 31 into 2 in. to 4 in. pieces. As the first outer scrim layer is moved by the conveyor belt, cut pieces of fiber roving 31 exit fiber chopper 30 and are spread along the first outer scrim layer at a rate of approximately 6 grams of cut pieces per foot of scrim. Fibers go in all directions (0 degrees, 10 degrees, 17 degrees, 23 degrees, 33 degrees, 36 degrees 40 degrees, 45 degrees, etc.) in order to create a pseudo-anisotropic product. A fine water mist may then be applied to the scrim and fiber pieces. This will facilitate the attachment of the fiber pieces and the compounded polypropylene mixture powder.

[0029] Continuing with FIG. 3, the compounded polypropylene mixture 41, now in powder or particulate form, is placed into polymer distribution chamber 40, which is configured to disperse compounded polypropylene mixture 41 along the first outer scrim layer at a rate of approximately 6-8 grams of compounded polypropylene mixture per foot of scrim.

[0030] A second outer scrim layer may then be placed over the first outer scrim layer via a second scrim roller 50 such that the fiberglass pieces and compounded polypropylene mixture are disposed between the first and second outer scrim layers. The combined layers may then be run through a series of rollers 60. The series of rollers may include three roller pairs 61, 62, and 63 wherein each pair comprises an upper roller and a lower roller. The combined layers are passed between the upper and lower rollers to apply pressure to both the first and second outer scrim layers thereby forming a completed composite structural laminate.

[0031] As shown in FIG. 3, fabrication of the composite structural laminate may also involve a series of heater units 70 and at least one cooler unit 80. The series of heater units 70 includes heaters units 71, 72, and 73. Heater unit 71 may be arranged between polymer distribution chamber 40 and second scrim roller 50. Heater unit 72 may be arranged between second scrim roller 50 and roller pair 61. Heater unit 73 may be arranged between roller pair 61 and roller pair 62. The heater units may be of any kind conventionally known in the art and be set to approximately 500 degrees Fahrenheit. The heat and compression applied by series of heater units 70 and series of rollers 60, respectively, serve to strengthen the adherence of the composite structural laminate's constituent components to one another. Cooler unit 80 may be arranged between roller pair 62 and roller pair 63. The cooler unit 80 may be of any kind conventionally known in the art and set between approximately 110-165 degrees Fahrenheit. After passing through roller pair 63, the formed composite structural laminate may be cut to a desired size.

[0032] The composite structural laminate and methods of production disclosed herein improve upon the conventional processes by incorporating graphene and both long and continuous fibers directly into the laminate. Embodiments of the presently disclosed processes are designed to create up to a 9.5 foot wide laminate at the rate up to 25 feet per minute on a single machine. There are no known conventional methodologies with this rate of production.

[0033] Referring to FIG. 3, one embodiment of an apparatus and method to produce a composite structural laminate has been described. Noting the advantageous aspects of the present disclosure above, improved consolidation of the various constituent components as previously described is achieved by the addition of nip rollers in critical locations: in-between heater units, before a cooler unit, and after the cooler unit. In conventional lamination processes there is no nip roller between heater units and between heater/cooler banks. The presently disclosed arrangement of nip rollers assists in the compaction of the fiber into the polypropylene and to spread the polypropylene to improve consolidation. Improved consolidation improves laminate strength.

[0034] Projected strengths of composite structural laminates produced according to the various embodiments of the present disclosure are between 12,000 to 22,000 psi tensile and a stiffness range of 800,000 to 1,000,000 psi. The materials being used, and the process of melting the products together, create an inert product, and the product does not give off gas volatile organic compounds (“VOCs”).

[0035] The amount of polypropylene and fiber used may be varied to produce laminates having different weights as may be needed to satisfy project-specific requirements, regulations, or restrictions. To vary the amount of polypropylene and/or fiber, the speed at which the individual component materials are applied to the bottom scrim layer may be adjusted while maintaining a constant speed for the conveyor system that ultimately results in the combination of the materials to make the laminate.

[0036] With respect to the application of polypropylene, in embodiments wherein rollers are used to deliver the polypropylene to the scrim, the speed of those rollers may be adjusted to meet the target polypropylene weight. Similarly, the speed at which the fiber is cut, or chopped, and delivered (via rollers or otherwise) may also be adjusted to meet the target fiber weight. Furthermore, the speeds of the respective delivery systems may be adjusted independently to provide greater variability of polypropylene and fiber weights in the laminate.

[0037] In certain embodiments of the present disclosure, the produced, consolidated laminate has a weight of 1,200 grams/sq. meter. Such a laminate may be composed of approximately 40-60% polypropylene and a corresponding 40-60% fiber wherein the respective percentages are relative to the total combined weight of polypropylene and fiber. For example, in the 1,200 grams/sq. meter laminate described previously, the laminate may contain approximately 650 grams/sq. meter of polypropylene (−54%) and 550 grams/sq. meter of fiber (−46%).

[0038] In other embodiments, laminates may be made having weights of 800 to 2,400 grams/sq. meter. In such embodiments, the laminate composition may include similar respective percentages of polypropylene and fiber as described above.

[0039] Another embodiment of a method of fabricating the composite structural laminate of this disclosure is depicted in FIG. 4. FIG. 4 adds the application of a water mist 91 from water misting device 90 after the initial deposition of the pieces of fiber roving 31 and the compounded polypropylene mixture 41, as illustrated in FIG. 3 described above. The water mist 91 may further improve attachment between the pieces fiber roving 31 and the compounded polypropylene mixture 41. Following application of the water mist 91, an additional round of depositions is performed of pieces of fiber roving 31 from an additional fiber chopper 30 and compounded polypropylene mixture 41 from an additional polymer distribution chamber 40. An additional heater unit 74 may be arranged between polymer distribution chamber 40 from the first deposition round and water misting device 90. In some embodiments, heater unit 74 may not be present. The same or similar amounts of pieces of fiber roving 31 and compounded polypropylene mixture 41 as were added in the first round may be deposited in this second round.

[0040] FIG. 5 illustrates an example composite structural laminate 500 and its composition. The composite structural laminate 500 includes a top scrim layer 502a (e.g., a top layer of fabric material from second scrim roller 50 of FIGS. 3 and 4) and bottom scrim layer 502b (e.g., a top layer of fabric material from first scrim roller 20 of FIGS. 3 and 4) between which an internal layer 504 is disposed. The internal layer 504 includes a polymer mixture 506 in which fibers 508 are dispersed. The fibers 508 are randomly distributed in the polymer mixture 506 (see FIGS. 6A and 6B). The internal layer 504 may have any appropriate thickness 510. For example, the thickness 510 may be in a range from about 1/16.sup.th of an inch to about ⅛.sup.th of an inch. The composite structural laminate 500 may be prepared as described with respect to FIGS. 3 and 4 above.

[0041] Each scrim 502a,b is a fabric material that may improves adhesion to, for example, adhesives, paint, and coatings. An exemplary scrim 502a,b is fabric that includes one or more of polyester, nylon, polyethylene, or similar. The top scrim layer 502a and bottom scrim layer 502b may be the same or different fabric materials. For example, the scrim rollers 20 and 50 of FIGS. 3 and 4 may dispense the same or different fabric materials.

[0042] The polymer mixture 506 includes polymer 512 and one or more of graphene 514, binder 516, and ultraviolet (UV) protectant 518. The polymer 512 may be any appropriate polymer, such as polypropylene, high density polypropylene, high density polyethylene, or the like. In some embodiments, the polymer 512 has a Melt Flow Rate (MFR) in a range from ten to sixty. A MFR is a measure of the flow of the polymer 512. The MFR of the polymer 512 may be determined, for example, according to established standards, such as ASTM D1238 and ISO 1133.

[0043] The graphene 514 may include any size and shape of graphene nanoplatelets. In some embodiments, the graphene 514 may be graphene nanoplatelets with a diameter of less than two micrometers and a thickness of in the range of one to tens of nanometers. The surface area of the graphene nanoplatelets may be in a range from about 100 to about 500 sq. meter/gram. In some embodiments, the surface area of the graphene nanoplatelets is about 300 sq. meter/gram.

[0044] The binder 516 may be any material or substance that promotes adhesion of the polymer 512 to the fibers 508. For example, in some embodiments, the binder 516 may be polypropylene grafted with maleic anhydride to improve adhesion between the polymer 512 and fibers 508. This binder 516 may be used to improve adhesion between a polypropylene polymer 512 and fibers 508. Another appropriate binder 516 may be selected for other types of polymer 512.

[0045] The UV protectant 518 may be any material that reduces the impact of exposure to UV radiation. For example, the UV protectant 518 may be any material that reflects and/or absorbs UV radiation to help prevent exposure to UV radiation or passage of UV radiation through the laminate 500.

[0046] The polymer mixture 506 may include at least 90% of the polymer 512, at least 1% of graphene 514, and at least 1% binder 516. In embodiments having the UV protectant 518, polymer mixture 506 may include at least 90% of the polymer 512, at least 1% of graphene 514, and at least 1% binder 516, and at least 0.15% of UV protectant 518. In some embodiments, the relative proportion of components of the polymer mixture 506 is: 92-97.5% polymer 512, 1.0-5% graphene 514, 1.5-3% binder 516, and 0-0.5% UV protectant 518.

[0047] The fibers 508 may be cut pieces of a fiberglass roving as described above with respect to FIGS. 2-4. The composite structural laminate 500 may have any relative proportion of polymer mixture 506 to fiber 508. For example, the amount of polymer mixture 506 and fiber 508 may be varied to produce laminates 500 having different weights as may be needed to satisfy project-specific requirements, regulations, and/or restrictions. In certain embodiments, the composite structural laminate 500 has a weight of about 1,200 grams/sq. meter. Such a laminate 500 may be composed of approximately 40-60% of polymer mixture 506 and a corresponding 40-60% of fibers 508, where the respective percentages are relative to the total combined weight of polymer mixture 506 and fiber 508. For example, in the 1,200 grams/sq. meter laminate 500, the laminate 500 may contain approximately 650 grams/sq. meter of polymer mixture 506 (54%) and 550 grams/sq. meter of fiber 508 (46%). In other embodiments, laminate 500 may have weights of 800 to 2,400 grams/sq. meter. In such embodiments, the laminate composition may include similar respective percentages of polymer mixture 506 and fiber 508, as described above.

[0048] The composite structural laminate 500 may have a tensile strength of between 12,000 to 22,000 psi tensile. The composite structural laminate 500 may have a stiffness range of 800,000 to 1,000,000 psi. These beneficial mechanical properties may be achieved at least in part based on the improved distribution of the fibers 508 that are dispersed within the polymer mixture 506, as described both above with respect to fibers 508 extending in all directions (e.g., 0 degrees, 10 degrees, 17 degrees, 23 degrees, 33 degrees, 36 degrees 40 degrees, 45 degrees, etc.) in order to create a pseudo-anisotropic product and below with respect to FIGS. 6A and 6B.

[0049] FIGS. 6A and 6B show the internal layer 504 from a top-down view (e.g., as would be seen looking from the top down in FIGS. 3 and 4). The internal layer 504 includes the polymer mixture 506 with fibers 508 randomly distributed and dispersed in the polymer mixture 506. A laminate 500 with internal layer 504 may have any appropriate width 602 for a given use. For example, the width 602 may be determined based in part on project-specific requirements, regulations, or restrictions and/or an available size of fabric material for the scrim layers 502a,b (see FIG. 5). FIG. 6B shows region 610 of FIG. 6A in greater detail. The fiber 508 shown in FIG. 6B is at an angle 614 relative to an axis 612 that extends parallel to a lengthwise direction 604 of the internal layer 504 of the laminate 500. The fibers 508 have randomly distributed values of angle 614, such that the fibers 508 extend in a wide variety of directions relative to axis 612 (e.g., 0 degrees, 10 degrees, 17 degrees, 23 degrees, 33 degrees, 36 degrees 40 degrees, 45 degrees, etc.), resulting in a pseudo-anisotropic product. This random distribution of the angle 614 of the fibers 508 facilitates further improved mechanical properties (e.g., tensile strength and stiffness) of the internal layer 504 and the overall laminate 500.

[0050] Modifications, additions, or omissions may be made to the systems, apparatuses, and methods described herein. The components of the systems and apparatuses may be integrated or separated. Moreover, the operations of the systems and apparatuses may be performed by more, fewer, or other components. The methods may include more, fewer, or other steps. Additionally, steps may be performed in any suitable order. Additionally, operations of the systems and apparatuses may be performed using any suitable logic. As used in this document, “each” refers to each member of a set or each member of a subset of a set.

[0051] Herein, “or” is inclusive and not exclusive, unless expressly indicated otherwise or indicated otherwise by context. Therefore, herein, “A or B” means “A, B, or both,” unless expressly indicated otherwise or indicated otherwise by context. Moreover, “and” is both joint and several, unless expressly indicated otherwise or indicated otherwise by context. Therefore, herein, “A and B” means “A and B, jointly or severally,” unless expressly indicated otherwise or indicated otherwise by context.

[0052] The scope of this disclosure encompasses all changes, substitutions, variations, alterations, and modifications to the example embodiments described or illustrated herein that a person having ordinary skill in the art would comprehend. The scope of this disclosure is not limited to the example embodiments described or illustrated herein. Moreover, although this disclosure describes and illustrates respective embodiments herein as including particular components, elements, feature, functions, operations, or steps, any of these embodiments may include any combination or permutation of any of the components, elements, features, functions, operations, or steps described or illustrated anywhere herein that a person having ordinary skill in the art would comprehend. Furthermore, reference in the appended claims to an apparatus or system or a component of an apparatus or system being adapted to, arranged to, capable of, configured to, enabled to, operable to, or operative to perform a particular function encompasses that apparatus, system, component, whether or not it or that particular function is activated, turned on, or unlocked, as long as that apparatus, system, or component is so adapted, arranged, capable, configured, enabled, operable, or operative. Additionally, although this disclosure describes or illustrates particular embodiments as providing particular advantages, particular embodiments may provide none, some, or all of these advantages.

[0053] The use of the terms “a” and “an” and “the” and similar referents in the context of describing the disclosure (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better explain the disclosure and does not pose a limitation on the scope of claims.