IMPACT AND PUNCTURE RESISTANT PANELS

Abstract: An impact and puncture resistant, corrosion resistant and lightweight panel (10) formed using a panel precursor comprising a plurality of laminae (12), each of the laminae (12) comprises a plurality of strands (16), each strand (16) comprises a plurality of fibers, including reinforcing fibers (17), and at least one polymeric material (19). The polymeric material (19) forms at least part of the matrix for the panel (10).

Description: IMPACT AND PUNCTURE RESISTANT PANELS CROSS-REFERENCE TO RELATED APPLICATIONS TECHNICAL FIELD AND INDUSTRIAL APPLICABILITY OF THE INVENTION The present invention relates to impact and puncture resistant panels and, more particularly, to impact and puncture resistant panels formed from strand material which includes reinforcing fibers and polymeric material. BACKGROUND OF THE INVENTION Impact and puncture resistant panels are useful in many applications, including as protective coverings for cash windows of financial institutions, coverings for kiosks and carts in open areas of shopping malls, side panels for tractor trailers, boat hulls, aircraft parts and other articles and parts for which impact resistance and/or puncture resistance are desired. By way of example only, the prior use of such panels as shutters or window covers shall now be described. Buildings and houses located in areas prone to severe weather conditions, such as hurricanes and tornados, are often exposed to wind borne debris during those severe weather conditions. Windows and doors, especially those made of glass, are most vulnerable to wind borne debris, such as tree branches, rocks and portions of surrounding structures. Shutters made of aluminum and steel are currently used to protect vulnerable portions of buildings and houses because shutters made from these materials can be manufactured to meet building and housing codes in regions which experience severe weather conditions. However, steel and even aluminum shutters undergo pitting and strength degradation associated with corrosion, particularly in regions along the sea coast, where the air contains a high concentration of corrosive salt. In addition, metal shutters can be somewhat heavy. Accordingly, there is a particular need for an impact and puncture resistant panel which can prevent the penetration of wind borne debris during severe weather conditions, is corrosion resistant and is relatively lightweight. There is also a more general need for an impact and puncture resistant panel that is relatively inexpensive to produce and readily adapted to various applications and strength requirements. SUMMARY OF THE INVENTION The present invention satisfies the current needs in the art by providing a panel precursor which can be used to produce an impact and puncture resistant panel, having a fiber reinforced polymeric matrix, which is relatively resistant to penetration, inexpensive, corrosion resistant and lightweight. The impact and puncture resistant panels of the present invention are formed using a panel precursor comprising a plurality of laminae. Each of the laminae comprises a plurality of strands, with each strand comprising a plurality of fibers, including reinforcing fibers, and at least one polymeric material. The polymeric material forms all, substantially all, or at least part, of the matrix for the panel. All of the matrix refers to the polymeric material from the strands providing all of the matrix except for that formed by any chemical treatment that may have been applied to the reinforcing fibers or any fiber made from the polymeric material. Substantially all refers to the polymeric material from the strands being enough to provide a matrix for all of the reinforcing fibers of the panel. It does not preclude the use of additional matrix material from a source other than the strands. A portion of the polymeric material of each of the laminae is fused to a portion of the polymeric material of another of the laminae so as to join the laminae together. In one embodiment, the plurality of laminae comprises a first lamina and a second lamina. Each of the laminae has a first plurality of the strands forming a first layer of strands and a second plurality of the strands forming a second layer of strands. A portion of the polymeric material from the first plurality of the strands is fused to a portion of the polymeric material from the second plurality of the strands so as to join the first plurality of the strands in an angular relation to the second plurality of the strands. Additionally, a portion of the polymeric material from the first lamina is fused to a portion of the polymeric material from the second lamina so as to join the first lamina at an angle to the second lamina. In another embodiment, the plurality of laminae comprises a first lamina and a second lamina. Each of the laminae has a plurality of the strands woven together. A portion of the polymeric material from the first lamina is fused to a portion of the polymeric material from the second lamina so as to join the strands of the first lamina in an angular relation to the strands of the second lamina. It may be desirable for a panel of the present invention to include lamina from each of the above two exemplary embodiments. The invention is also directed to an impact and puncture resistant shutter comprising a plurality of panels operatively adapted for being secured to the exterior of a building. Each of the panels is produced using the present panel precursors. The objectives, features and advantages of the present invention will become apparent upon consideration of the following detailed description, accompanying drawings and appended claims. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 presents a cutaway view showing the laminae of a panel formed according to one embodiment of this invention. Fig. 2 presents a cutaway view showing the laminae of a panel formed according to another embodiment of this invention. Fig. 3 present a cutaway view of a modification of the panel of Fig. 2. Fig. 4 presents a perspective view of a plurality of panels of this invention in the form of a shutter. Fig. 4A presents a sectional view of the shutter shown in Fig. 4, taken along lines 4A-4A. Fig. 5 presents a perspective view of a plurality of panels of this invention in the form of an alternate shutter. Fig. 5 A presents a sectional view of the shutter of Fig. 5, taken along lines 5A-5A. Fig. 6 presents a perspective view of a plurality of panels of this invention in the form of a window covering. Fig. 6A presents an enlarged view of a portion of Fig. 6 showing the manner in which the window covering of Fig. 6 can be attached to a wall. Fig. 6B presents a sectional side view of a latch mechanism that can be used to attach the window covering of Fig. 6 to a wall. Fig. 7 presents a perspective view of a plurality of panels of this invention in the form of another alternate shutter. Fig. 7 A presents a sectional view of the shutter shown in Fig. 7, taken along lines 7A-7A. Fig. 8 presents a perspective view of a plurality of panels of this invention in the form of an additional alternate shutter. Fig. 8 A presents a sectional view of the shutter shown in Fig. 8, taken along lines 8A-8A. DETAILED DESCRIPTION AND PREFERRED EMBODIMENTS OF THE INVENTION The present invention is directed to an impact and puncture resistant panel 10. The present panel 10 is a lamination comprising a plurality of laminae 12, each of which is formed from a plurality of reinforcement strands 16. Each strand 16 includes a plurality of reinforcing fibers 17 and at least one polymeric material 19. Useful reinforcing fibers can be any suitable reinforcing fiber including those selected from the group consisting of E-glass fibers, S-glass fibers, graphite fibers, aramid fibers, silicon carbide fibers, other fibers having suitable reinforcing characteristics and various combinations thereof. The polymeric material 19 can be any suitable polymeric material including a thermoplastic polymeric material selected from the group consisting of polyamides, polypropylenes, polyesters, polyethylenes, polyphenylene sulfides and other like thermoplastic materials. The polymeric material 19 may be in the form of polymeric fibers which are commingled or combined with one or more reinforcing fibers 17 to form the strands 16. Methods for making commingled reinforcing and polymer fiber strands are disclosed in detail in copending U.S. Patent Application Serial No. 08/311,817 filed September 26, 1994 (Attorney Docket 23422A) and entitled "METHOD AND APPARATUS FOR FORMING COMPOSITE STRANDS," by Andrew B. Woodside et al. The applicants hereby incorporate by reference the '817 application in its entirety. If commingled reinforcing-polymer fibers are used, it is desirable, though not required, for the weight ratio of reinforcing fibers to polymer fibers to range from about 40/60 to about 60/40. It can be more desirable for the weight ratio of reinforcing fibers to polymer fibers to be about 50:50. Alternatively, the strands 16 may comprise a plurality of the reinforcing fibers 17 with the polymeric material 19 wire-coating or otherwise forming a layer around the reinforcing fibers 17 of each strand 16. These coated strands 16 may also include fibers made of the polymeric material 19 that are commingled with the reinforcing fibers 17. In addition, it may be desirable to use any combination of the above described strands 16 in making a panel 10 according to the present invention. Examples of such strands 16 are disclosed in copending U.S. Patent Application Serial No. 08/695,909, filed August 12, 1996, and entitled "CHEMICAL TREATMENTS FOR FIBERS AND WIRE- COATED COMPOSITE STRANDS FOR MOLDING FIBER-REINFORCED THERMOPLASTIC COMPOSITE ARTICLES," by Andrew B. Woodside, and in copending U.S. Patent Application Serial No. 08/695,504, filed August 12, 1996, and entitled "CHEMICAL TREATMENTS FOR FIBERS AND WIRE-COATED COMPOSITE STRANDS FOR MOLDING FIBER-REINFORCED THERMOPLASTIC COMPOSITE ARTICLES," by Andrew B. Woodside, the disclosures of which are hereby incorporated by reference. Whether the strands 16 are formed by wire coating, commingling reinforcing and polymer fibers, or a combination thereof, it may or may not be desirable for the resulting strands 16 to be sized, impregnated or preimpregnated with a suitable chemical treatment. The cohesiveness of the fibers forming each of the strands 16 may be maintained by means of a suitable aqueous, nonaqueous, or solvent free chemical treatment. The chemical treatment can be applied so as to size the fibers before they are formed into a strand 16. However, to insure the cohesiveness of the fibers, it is desirable for the chemical treatment to be applied to the fibers in a sufficient amount to also at least partially, if not fully, preimpregnate the resulting strand 16. As an alternative, the chemical treatment can be partially or fully impregnated into a formed strand 16. One chemical treatment that has been applied to maintain the cohesiveness of the fibers in the strand 16 is an aqueous based urethane chemical treatment available from Reichhold Chemicals of Raleigh-Durham, North Carolina, under the product identification number 97903. Another chemical treatment that has been used with the strands 16 is a non-aqueous based polyester chemical treatment. This polyester chemical treatment is a polyester resin available from Alpha/Owens-Corning of Collierville, Tennessee, under the product identification number E830. To produce this polyester chemical treatment, 1% by weight of benzoyl peroxide powder is mixed into 5% by weight styrene. This styrene/benzoyl peroxide mixture is then mixed with 2% by weight of the silane gamma-methacryloxypropyltrimethoxysilane (A 174), available from Witco Chemical Company of Chicago, Illinois, and 92% by weight of the polyester resin E830. For the present panels 10, a suitable chemical treatment is one which is compatible with the polymeric material 19. In general, for a composite article to exhibit satisfactory mechanical properties between its reinforcing fibers and matrix material, it is desirable for any chemical treatment applied to the reinforcing fibers to be compatible with the matrix material. Likewise, for the panel 10, it is desirable for any chemical treatment being used in the strands 16 to be compatible with the polymeric material 19, which forms at least part of the matrix for the reinforcing fibers 17 of each panel 10. In general, a chemical treatment is considered compatible with the polymeric material if it is capable of interacting with and/or reacting with the polymeric material. In addition, a chemical treatment can be considered compatible if stress loads (static or dynamic), applied to a panel 10 formed using such a chemical treatment, are transferable from the polymeric material 19 to the reinforcing fibers 17 or from the fibers 17 to the polymeric material 19 through the chemical treatment formed as an interface therebetween. The applied chemical treatment may comprise the same type of material as the polymeric material. In addition, the compatible chemical treatments may be miscible in the polymeric material, in whole or in part, and/or may form a separate phase from the polymeric material. Referring to Fig. 1, one embodiment 11 of the panel 10 comprises a plurality of laminae 12, four of which are shown in Fig. 1 for illustration purposes. The panel 11 includes a first lamina 14, a second lamina 18, a third lamina 20 and a fourth lamina 22. Each lamina 14, 18, 20 and 22 comprises a plurality of strands 16 which each comprises a plurality of reinforcing fibers 17 and at least one polymeric material 19. The laminae 14, 18, 20, and 22 are joined together by fusing a portion of the polymeric material 19 of one lamina 12 with a portion of the polymeric material 19 of another lamina 12. For example, polymeric material 19 from the strands 16 of the lamina 14 fuses with the polymeric material 19 from the strands 16 of the lamina 18; polymeric material 19 from the strands 16 of the lamina 18 fuses with the polymeric material 19 from the strands 16 of the lamina 20; and polymeric material 19 from the strands 16 of the lamina 5 20 fuses with the polymeric material 19 from the strands 16 of the lamina 22. For any panel 10, the polymeric material 19 of the laminae 12 are sufficiently melted and fused together to provide the panel 10 with the mechanical properties desired. The polymeric material 19 from each of the strands 16 forms all, substantially all, or at least part, of the matrix for the reinforcing fibers 17 of each panel 10 10, according to the present invention. All of the matrix refers to the polymeric material 19 from the strands 16 providing all of the matrix except for that formed by any chemical treatment that may have been applied to the reinforcing fibers 17 or any fibers made of the polymeric material 19. Substantially all of the matrix refers to the polymeric material 19 from the strands 16 being enough to provide a matrix for all of the reinforcing fibers 17 in 15 the panel 10. It does not preclude the use of additional matrix material from a source other than the strands 16. In the exemplary panel 11, the various lamina 14, 18, 20 and 22 are positioned angularly in relation to each other. The first lamina 14 is arranged angularly to the second lamina 18 which is arranged angularly to the third lamina 20. The third lamina 20 20 is arranged angularly to the fourth lamina 22. By arranging the various lamina in this manner, the panel 11 is provided with reinforcement against loads applied along both its machine direction (i.e., length) and its cross machine direction (i.e., width). The strands 16 forming any lamina of a panel 11 can be positioned next to each other or they can be spaced apart. For some applications, a porous panel 11 is desirable. For example, having 25 a porous panel 11 would allow air to flow through the panel 11 in order to compensate for air pressure differences on either side of the panel 11. For such an application, the strands 16 in each lamina of a panel 11 can be sufficiently spaced apart to form openings through the panel 11. Laminae having strands spaced up to about 1 inch (2.54 cm) apart have been produced. It is believed that panels 11 with laminae having strands 16 spaced even 30 further apart can also be successfully produced. As shown in Fig. 1, each of the laminae 14, 18, 20 and 22 is in the form of a reinforcement mat 24 which has a first layer 26 of the strands 16 and a second layer 28 of the strands 16. The first and second layers 26 and 28 are positioned relative to one another so that their strands 16 of one layer 26 are at an angle θ from the strands 16 of the 5 other layer 28. It is desirable for the angle θ to be in the range of from about 6° to about 174°. It is more desirable for the angle θ to be in the range of from about 60° to about 120°. The first layer 26 of strands 16 is angularly positioned in relation to the second layer 28 of strands 16 so that each lamina 12 can more efficiently carry loads. During the formation process of mat 24, the first and second layers 26 and 10 28 are brought together and heated such that at least a portion of the polymeric material 19 incorporated into the first and second layers 26 and 28 bond together so as to join the strands 16 of the first and second layers 26 and 28 to one another to form the mat 24. In other words, the polymeric material 19 of the layers 26 and 28 are sufficiently fused together to provide the lamina 12 with the mechanical properties desired. The process for 15 forming such a mat 24 and a description of the mat 24 are set out in copending United States Patent Application Serial No. 08/713,319 (Attorney Docket No. 24084A) entitled "PROCESS AND APPARATUS FOR MAKING A REINFORCING MAT" and in copending U.S. Patent Application Serial No. 08/713,318 (Attorney Docket No. 23689A) entitled "A REINFORCEMENT MAT." Both of these applications are hereby 20 incorporated by reference in their entireties. As an option, one or more of the mats 24 of the panel 11 can further include a third layer 30 of the strands 16. The strands 16 of the layer 30 run lengthwise or in the machine direction of the mat 24. The polymeric material 19 from the layer 30 is sufficiently fused with the polymeric material 19 from one or more of the other layers 26 25 and 28. Each mat 24 may also include a layer or film 31 of polymeric material sandwiched between and fused to any two of the layers 26, 28, and/or 30 to serve as part of the matrix for the reinforcing fibers 17. As stated above, the laminae 12, which form the panel 11, or other of the present panels 10, can be positioned in an angular relation to each other. Particularly, 30 each of the laminae 12 can be positioned in an angular relation to the lamina 12 on one or either side thereof. It is desirable for the angle between two adjacent laminae 12 to be in the range from about 30° and about 150°. It is more desirable for the angle between consecutive laminae 12 to be in the range of from about 60° and about 120°. It can be even more desirable for the laminae 12 to be arranged approximately perpendicular to each other (i.e., at an angle of about 90°). The panel 11 can be formed from two to sixteen of the laminae 12, such as the reinforcement mats 24 described above, or possibly even more of the laminae 12. It can be desirable for the panel 11 to be formed from six to twelve, or even from eight to ten, of the laminae 12, such as the reinforcement mats 24 described above. The panel 11, or other of the present panels 10, may be further reinforced by means of additional reinforcing materials including those selected from the group consisting of glass fibers, graphite fibers, aramid fibers, silicon carbide fibers and other fibers having suitable reinforcing properties and combinations thereof. It can be desirable for these additional reinforcing materials to be formed into nonwoven or woven mats 43 (see Figs. 2 and 3). By "nonwoven", it is meant that the reinforcing materials in the mat are not systematically woven together. One such reinforcing material is a nonwoven glass fiber mat, such as the continuous strand mats available from Owens Corning, of Toledo, Ohio, under the product designations M8608 and M8610. These types of mats are made of glass fibers laid in a continuous swirl pattern. Nonwoven glass fiber mats can be formed by air laying glass fibers into a mold and compressing the fibers together in the mold to form the mat. One nonwoven glass fiber mat 43 can be sandwiched between one or more pairs of adjacent laminae 12, the laminae 12 can be sandwiched between a pair of the nonwoven glass fiber mats 43 (see Figs. 2 and 3), or both. The panel 11, or other of the panels 10, may also include a surface finish to enhance the appearance and/or to further protect the panel. It is desirable for the surface finish to have good weatherability. Useful surface finishes include, for example, plastic films, ultraviolet protectants, water repellents, canvases (e.g., awning material) and glass mats such as those described above. Referring to Fig. 2, another embodiment 41 of the panel 10 comprises laminae 12 formed from strands 16 which are woven together by means of one or more threads 53 running at an angle (e.g., transversely) to the strands 16 to form woven mats 54. The example of the panel 41 shown in Fig. 2 includes a first lamina 42, a second lamina 44, a third lamina 46, a fourth lamina 48 and a fifth lamina 50. Each of the laminae 44, 46, 48 and 50 comprises a plurality of strands 16 which each comprise a plurality of reinforcing fibers 17 and at least one polymeric material 19. The laminae 44, 46, 48 and 50 are positioned between a pair of lamina 42 (one shown in Fig. 2) which 5 each comprises additional reinforcing materials, such as that described above. In the embodiment shown, the additional reinforcing materials forming the lamina 42 are nonwoven mats 43. In the embodiment shown in Fig. 2, the first and second laminae 44 and 46 are arranged with their strands 16 parallel to each other and the third and fourth laminae 10 48 and 50 are arranged with their strands 16 parallel to each other. The first and second woven lamina 44 and 46 are arranged in an angular relation, here about 90°, to the third and fourth woven lamina 48 and 50. The angular arrangement of the laminae 44, 46, 48 and 50, as shown or at any other angle, provides the panel 10 with reinforcement in both its machine direction and its cross machine direction, i.e., along both its length and its 15 width. In one modification of the panel 41, six laminae 12, formed from woven mats such as mat 54, are arranged in pairs, with the strands 16 in each pair being oriented in the same direction. A first pair of the woven mats 54 is sandwiched between a second pair and a third pair of the woven mats 54. The strands 16 of the first pair of mats 54 are 20 positioned in an angular relation to the strands 16 of both the second and third pairs of mats 54. to form a laminated structure. This laminated structure is sandwiched between a pair of nonwoven fiber mats 43. The strands 16 of the panels 41 can be woven together by means of a conventional weaving process known in the art to weave glass fibers into mats 54. Typically, the strands 16 are woven together by threads 53 25 running transverse to the strands 16. These threads 53 can be made from any suitable thread fiber including those selected from the group consisting of glass fibers, nylon fibers, polyamide fibers, polypropylene fibers, polyester fibers, polyethylene fibers, and polyphenylene sulfide fibers. It can be desirable for the thread 53 to be formed from the same material as the polymeric material 19 used in the strands 16. Another strand 16 30 could also be used for the thread 53. To maintain the strands 16 in position in the woven mat 54 and to prevent fraying, the edges of the mat 54 can be stitched after the strands 16 have been woven together. The ends of the strands 16 can also be heated to at least partially melt the polymeric material 19 and, thereby, prevent movement of individual fibers in the strands 5 16. Such heating is particularly desirable with commingled strands 16. The panel 41 can be formed from two to sixteen or even more laminae 12, such as the woven mats 54, and additional reinforcing materials, such as nonwoven fiber mats 43. It is desirable for the panel 41 to be formed from four to twelve, or even more, of such laminae 12, depending on the diameter of the strands 16 and the application for 10 which the panel 41 is being used. Referring to Fig. 3, an alternative panel 41 comprises a first lamina 62 formed from an additional reinforcing material which, in the embodiment shown, is a nonwoven glass fiber mat 43; a second lamina 64 formed from a woven mat 54; a third lamina 66 formed from a woven mat 54; and a fourth lamina 68 formed from a woven mat 15 54. The second lamina 64 is shown with its strands 16 oriented angularly, as shown about 90°, in relation to the strands 16 of the third lamina 66. The strands 16 of the fourth lamina 68 are shown as being positioned about parallel to the strands 16 of the second lamina 64 (i.e., about perpendicular to the strands 16 of the third lamina 66). However, the laminae 62, 64, 66 and 68 can be oriented in any desired manner to reinforce the 20 alternative panel 41. Again, by positioning the various woven laminae 64 and 66 angularly in relation to each other, the panel 41 is provided with reinforcement against loads applied along both its machine direction (i.e., length) and its cross machine direction (i.e., width). In another modification of the panel 41, an additional reinforcing material, 25 such as a woven or nonwoven mat 43 made from aramid fibers, is positioned between a first lamina and a second lamina, both of which are formed from woven fiber mats, such as the mat 54. The first lamina is positioned with its strands 16 in an angular relation to those of the second woven lamina. A third lamina, formed from a woven fiber mat, such as the mat 54, is layered on the first lamina with its strands 16 in an angular relation to 30 those of the first lamina. A fourth lamina, formed from a woven fiber mat, such as the mat 54, is layered on the second lamina with its strands 16 positioned in an angular relation to the strands 16 of the second lamina to form a laminated structure. This laminated structure is sandwiched between two layers of additional reinforcing materials, such as the nonwoven fiber mats 43 described above. The panel 10 can be formed by any suitable molding process such as, for 5 example, compression molding, transfer molding or injection molding. The individual laminae 12 can be formed by the process described in United States Patent Application Ser. No. 08/713,318, incorporated by reference above, by a conventional weaving process, or any other suitable process, depending upon which type of laminae 12 will be used. After the separate laminae 12 have been formed, they are positioned in a mold cavity, for 10 example, of a compression molding, transfer molding or injection molding apparatus. During this time, the optional additional reinforcing materials, such as the woven and/or nonwoven fiber mats 43 and surface finishes, can be positioned in the mold. The laminae 12 are then compressed, or pressure otherwise applied, to form a panel 10. As the laminae 12 are being compressed, the mold is heated to cause portions of the polymeric material 15 19 of the strands 16 from the separate lamina 12 to fully, or at least partially, melt and fuse or bond to each other and to bond to other polymeric material 19 in other laminae 12. After the panel 10 has been compressed to a desired thickness and density, it is removed from the mold and can be painted, coated with a protective coating and processed further if necessary. In addition, the final surface finish (e.g., a canvas) can be incorporated as an 20 integral part of the panel 10 by including the surface finish in the molding process. Examples Panels were formed according to the above described method and were tested to determine their tensile stress, tensile modulus, flexural stress, flexural modulus, notched Izod and high rate impact strength. For comparison purposes, a glass fiber mat 25 infiltrated with a thermoplastic material (GMT) was also tested. The panels tested had the following configurations: Panel A - This panel was formed from 12 laminae. The individual lamina were reinforcement mats formed by the process described in United States Patent Application Ser. No. 08/713,318, incorporated by reference above, using commingled glass and 30 polypropylene fibers. First portions of the strands of each lamina were arranged at a 90° angle to second portions of the strands of each lamina to form a reinforcement mat such as the mats 24 described above. The odd numbered lamina were positioned at a 90° angle to even numbered lamina. In other words, alternating lamina were arranged at a 90° angle to each of the other laminae. Panel B - This panel had the same configuration as panel A with each side of the panel being covered with a layer of generic polypropylene film. Panel C - This panel was formed using the laminae formed from woven mats such as mat 54 described above. The woven mats were formed from strands comprising commingled glass reinforcing fibers and polypropylene fibers. In this panel, a first pair of laminae was positioned between a second pair of laminae and a third pair of laminae. The strands in laminae forming each pair were substantially parallel to each other. The first pair of laminae was positioned at a 90° angle to the second and third pair of laminae. The entire structure was then sandwiched between two nonwoven glass fiber mats. Panel D - This panel was formed using laminae formed from woven mats, such as mat 54 described above, comprising commingled glass-polypropylene fibers. In this panel a woven mat made of glass fibers, such as mat 54 described above, was positioned between first and second laminae formed from woven mats. The first and second laminae were positioned with their strands at a 90° angle to each other. The first and second laminae were then positioned between third and fourth lamina. The third lamina was positioned adjacent the first lamina at a 90° angle to the first lamina and at a 0° angle to the second lamina. The fourth lamina was positioned adjacent the second lamina at a 90° angle to the second lamina and at a 0° angle to the first lamina. The above tests were performed according to the indicated ASTM testing standards except for the "High Rate Impact" test which was performed on a Rheometrics Model RHIT-8000 High Rate Impact Tester. The test results were as follows: PANEL A PANEL B PANEL C PANEL D GMT MD/CD 1 MD/CD MD/CD MD/CD Tensile Stress 2 12.69 9.97 6.40 25.33 1 1.25 (10 3 psi) [MPa] [87.5] [68.7]/ [44.1]/ [174.6]/ [77.6]/ 10.27 8.44 12.65 15.63 [70.8] [58.2] [87.2] [107.8] Tensile Modulus 3 0.83 0.555 0.528 1.096 0.853 (10 6 psi) [10 3 MPa] [5.723] [3.827]/ [3.640]/ [7.557]/ [5.881]/ 0.655 0.857 0.639 1.02 [4.516] [5.909] [4.406] [7.033] Flexural Stress 4 18.16 6.59 6.72 15.00 18.17 (10 3 psi) [MPa] [125.2] [45.4]/ [46.3]/ [103.4]/ [125.3]/ 8.27 8.70 6.72 10.13 [57.0] [60.0] [46.3] [69.8] Flexural Modulus 5 0.78 0.386 0.309 1.252 0.828 (10 6 psi) [10 MPa] [5.378] [2.661]/ [2.130]/ [8.632]/ [5.709]/ 0.491 0.364 0.269 0.507 [3.385] [2.510] [1.855] [3.496] Notched Izod 6 4.8 31.38/ 34.79/ 35.22/ 23.46/ (ft-lb) 26.64 39.17 25.10 21.33 High Rate Impact 235 662 620 374 373 (in-lb) Notes: 1 - Machine Direction/Cross Machine Direction 2 - ASTM D 638 3 - ASTM D 638 4 - ASTM D 790 5 - ASTM D 790 6 - ASTM D 256 These tests demonstrate that these panels have an improved strength for both impact resistance and puncture resistance. The panel 10 of this invention can be used to make storm shutters either individually or by combining a plurality of panels. The panels 10 are also useful to make protective coverings for cash windows of financial institutions, coverings for kiosks and carts in open areas of shopping malls, side panels for tractor trailers, boat hulls, aircraft parts and other articles and parts for which impact resistance and/or puncture resistance are desired. Fig. 4 presents a perspective view of the panels of this invention being combined to form a shutter or window covering 100. The shutter 100 comprises a series of panels 102 each having interlocking lips 104 as shown in Fig. 4A. The panels 102 remain hidden behind a shutter facade 106 until they are needed to protect the window 108. To move the panels 102 into position to protect window 108, the panels are pulled from behind facade 106 and slid along a track 110. As they are pulled, their lips 104 interlock to pull successive panels from behind facade 106. The interlocking lips 104 also help to prevent penetration of airborne debris and precipitation through shutter 100 to window 108. Fig. 5 presents a perspective view of the panels of this invention being combined to form another shutter 200. The shutter 200 comprises a plurality of panels 202, each having a first lip 204 and a second lip 206, as shown in Fig. 5A. The panels 202 are stored in a box 208 under the window 210. The panels 202 are moved into position to protect window 210 by means of an interiorly or exteriorly mounted crank or pull cord. The first lip 204 of the first panel 212 is mounted on a slide bar 214 which pulls the panels 202 into position. As the panels 202 are raised, the second lip 206 on one panel engages the first lip 204 on the panel beneath it to raise that panels to cover the window 210. Again, the interlocking nature of the panels 202 helps to protect the window 210 from the penetration of airborne debris and precipitation through shutter 200 to window 210. Fig. 6 presents a perspective view of the panels of this invention being employed as another type of window covering. In this embodiment, a series of panels 300 are separately mounted to protect a window 302. The panels 300 each include interlocking lips or edges (not shown) to help prevent the penetration of airborne debris and precipitation to the window 302. The upper portion of each panel 300 includes an edge portion 304 which engages a bracket 306 mounted over the top of the window 302, as shown in Fig. 6A. Bracket 306 may also include a rubber gasket 308 to further prevent the penetration of water through panel 300 to window 302. Fig. 6B presents a cross sectional view of one of the panels 300. Each panel 300 includes a latch mechanism 310 which is used to attach the panel 300 to a mount 312 on a wall 314 surrounding the window 302. Thus, each panel 300 is secured in position over the window 302 by means of the engagement of edge portion 304 with bracket 306 and the engagement of latch mechanism 310 with mount 312 on wall 314. Fig. 7 presents a perspective view of the panels of this invention being used to form an alternate shutter 350 which simulates roofing tile. The shutter 350 comprises a series of panels 352 which are rotatably mounted over a window 354. Each panel 352 includes lips 356, shown in Fig. 7A, which engage each other to prevent the separate panels 352 from being extended past the point of engagement of each panel and to help prevent the penetration of precipitation and wind borne debris from contacting the window 354. Fig. 8 presents a perspective view of the panels of this invention being used to form another alternate shutter 400 which simulates roofing tile. In this embodiment, the shutter 400 includes a facade section 402, a first section 404 and a second section 406. Rather than sliding into position to cover a window 408, the shutter 400 is hinged so that first section 404 and second section 406 unfold from beneath facade section 402 to cover window 408. Second section 406 can be held in a closed position by securing clips 412 which can be rotatably mounted beneath window 408. When folded into a position at which it is not covering window 408, shutter 400 includes an arm 410 which can be used to brace shutter 400 in an open position. While certain representative embodiments and details have been shown for the purpose of illustrating the invention, it will be apparent to those skilled in the art that various changes in the product and method described herein may be made without departing from the scope of the invention, which is defined in the appended claims.

Claims: CLAIMS 1. A precursor for an impact and puncture resistant panel having a fiber reinforced polymeric matrix, said precursor comprising a plurality of laminae, each of said laminae comprising a plurality of strands, each strand comprising a plurality of fibers, including reinforcing fibers, and at least one polymeric material, said polymeric material forming at least part of the matrix for the panel. 2. The panel precursor of claim 1, wherein said polymeric material forms substantially all of the matrix for the panel. 3. The panel precursor of claim 1, wherein said polymeric material of at least one strand comprises at least one of a plurality of polymer fibers commingled with said reinforcing fibers of said one strand and a layer of polymeric material wire-coating said fibers of said one strand. 4. The panel precursor of claim 1 , wherein said plurality of laminae further comprises a first lamina and a second lamina, each of said lamina has a first plurality of said strands forming a first layer and a second plurality of said strands forming a second layer, said first plurality of said strands are in an angular relation to said second plurality of said strands, and said first lamina is at an angle to said second lamina. 5. The panel precursor of claim 4, wherein said plurality of laminae comprises six of said first lamina and six of said second lamina, said lamina being layered so as to form a panel precursor of twelve laminae of alternating first lamina and second lamina, and each said first lamina is at an angle to each said second lamina. 6. The panel precursor of claim 1 , wherein said panel precursor further including two layers of polymer film between which said laminae are sandwiched. 7. The panel precursor of claim 1 , wherein said plurality of laminae further comprises a first lamina and a second lamina, each of said lamina has a plurality of said strands woven together, and said strands of said first lamina are in an angular relation to said strands of said second lamina. 8. The panel precursor of claim 7, wherein said panel precursor further comprises a pair of nonwoven reinforcing fiber mats between which said first and second lamina are sandwiched. 9. The panel precursor of claim 8, wherein said panel precursor further comprises a reinforcing fiber mat sandwiched between said first and second lamina. 10. The panel precursor of claim 7, wherein said panel precursor further comprises a reinforcing fiber mat sandwiched between said first and second lamina. 11. The panel precursor of claim 1 , wherein said panel precursor further comprises at least one surface finish from the group consisting of plastic films, ultraviolet protectants, water repellents, canvases, glass mats and combinations thereof. 12. An impact and puncture resistant panel, having a fiber reinforced polymeric matrix, produced according to the method comprising the steps of: providing a panel precursor comprising a plurality of laminae, each of the laminae comprising a plurality of strands, each strand comprising a plurality of fibers, including reinforcing fibers, and at least one polymeric material, the polymeric material forming at least part of the matrix for the panel; and fusing a portion of the polymeric material of each of the laminae to a portion of the polymeric material of another of the laminae so as to join the laminae together. 13. The panel of claim 12, wherein said step of providing a panel precursor includes providing strands with enough of the polymeric material to from substantially all of the matrix for the panel. 14. The panel of claim 12, wherein said step of providing a panel precursor includes providing a first lamina and a second lamina, with each of the lamina having a first plurality of the strands forming a first layer and a second plurality of the strands forming a second layer, said step of fusing includes fusing a portion of the polymeric material from the first plurality of the strands to a portion of the polymeric material from the second plurality of the strands so as to join the first plurality of the strands in an angular relation to the second plurality of the strands, and said step of fusing includes fusing a portion of the polymeric material from the first lamina to a portion of the polymeric material from the second lamina so as to join the first lamina at an angle to the second lamina. 15. The panel of claim 14, wherein said step of providing a panel precursor includes providing twelve laminae of alternating first lamina and second lamina, with each first lamina being at an angle to each second lamina, and said step of fusing includes fusing a portion of the polymeric material from each the first lamina to a portion of the polymeric material from at least one of the second lamina so as to join all of the lamina together into a panel. 16. The panel of claim 12, wherein said method further comprises at least one of the steps of forming at least one strand by commingling at least one fiber made from the polymeric material with the reinforcing fibers of the one strand, and forming at least one strand by wire-coating the fibers of the one strand with a layer of the polymeric material. 17. The panel of claim 12, wherein said step of providing a panel precursor includes providing a lamina with at least one strand with its polymeric material comprises at least one of a layer of polymeric material wire-coating the fibers of the one strand and a plurality of polymer fibers commingled with the reinforcing fibers of the one strand. 18. The panel of claim 12, wherein said method further comprises at least one of the steps of sizing the fibers in a plurality of the strands with a chemical treatment, pre-impregnating a plurality of the strands with a chemical treatment, and impregnating a plurality of the strands with a chemical treatment. 19. The panel of claim 12, wherein said method further comprises the step of providing two layers of polymer film between which the laminae are sandwiched, and said step of fusing includes fusing a portion of the polymeric material from one of the laminae to one of the layers and a portion of the polymeric material from another of the laminae to the other of the layers so as to join the layers to the laminae. 20. The panel of claim 12, wherein said step of providing a panel precursor includes providing a first lamina and a second lamina, with each of the lamina having a plurality of the strands woven together and the strands of the first lamina being in an angular relation to the strands of the second lamina, and said step of fusing includes fusing a portion of the polymeric material from the first lamina to a portion of the polymeric material from the second lamina so as to join the first lamina and the second lamina. 21. The panel of claim 20, wherein said step of providing a panel precursor includes providing a pair of nonwoven reinforcing fiber mats between which the first and second lamina are sandwiched, and said step of fusing includes fusing a portion of the polymeric material from one of the laminae to one of the mats and a portion of the polymeric material from another of the laminae to the other of the mats so as to join the mats to the laminae. 22. The panel of claim 21 , wherein said step of providing a panel precursor includes providing a reinforcing fiber mat sandwiched between the first and second lamina, and said step of fusing includes fusing a portion of the polymeric material from each of the first and second lamina to the mat so as to join each of the first and second lamina to the mat. 23. The panel of claim 20, wherein said step of providing a panel precursor includes providing a reinforcing fiber mat sandwiched between the first and second lamina, and said step of fusing includes fusing a portion of the polymeric material from each of the first and second lamina to the mat so as to join each the first and second lamina to the mat. 24. The panel of claim 12, wherein said step of providing a panel precursor includes providing at least one surface finish from the group consisting of plastic films, ultraviolet protectants, water repellents, canvases, glass mats and combinations thereof. 25. The panel of claim 12, wherein said step of fusing includes fusing a portion of the polymeric material of at least one of the laminae to at least a portion of a surface finish. 26. An impact and puncture resistant shutter, comprising a plurality of panels operatively adapted for being secured to the exterior of a building, each panel having a fiber reinforced polymeric matrix and being produced according to the method comprising the steps of: providing a panel precursor comprising a plurality of laminae, each of the laminae comprising a plurality of strands, each strand comprising a plurality of fibers, including reinforcing fibers, and at least one polymeric material, the polymeric material forming at least part of the matrix for the panel; and fusing a portion of the polymeric material of each of the laminae to a portion of the polymeric material of another of the laminae so as to join the laminae together.

Inventors: MACDONALD FRANK J, WOODSIDE MARGARET M, MACDONALD, FRANK, J., WOODSIDE, MARGARET, M.
Applicants: OWENS CORNING FIBERGLASS CORP, OWENS CORNING
Application year: 1998
Main classification: B32B5
IPC codes: B29C70, B32B5, E06B9, F41H5