Structural Materials

Abstract

There is described a structural sheet or protective panel, comprising a layer of self-reinforced polyolefin; a layer of polymer foam, wherein the layer of self-reinforced polyolefin and polymer foam are bonded together to form a laminated structure. The structural sheets (alone or in combination with other structural sheets) can be configured as protective structures. Protective panels, roof panels, window or door shutters, running boards and fencing panels are described.

Claims

1. A structural sheet, comprising: a layer of self-reinforced polyolefin; a layer of polymer foam; the layer of self-reinforced polyolefin and polymer foam bonded together to form a laminated structure.

2-41. (canceled)

Description

LIST OF FIGURES SHOWING SPECIFIC EMBODIMENTS

[0116] The present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0117] FIG. 1 shows a structural sheet;

[0118] FIG. 2 shows a further example of a structural sheet;

[0119] FIG. 3 shows a still further example of a structural sheet with localised bonding;

[0120] FIG. 4 shows a further example of a structural sheet with perimeter bonding;

[0121] FIG. 5 shows a window frame and window louvres configured from structural panels comprising the described laminated structure;

[0122] FIG. 6 shows a roller shutter configured from structural panels comprising the described laminated structure;

[0123] FIG. 7 shows a possible structure for a protective shutter or blind formed from structural panels;

[0124] FIG. 8 shows field fencing or protective barriers formed using the described structural panels;

[0125] FIG. 9 shows the use of the described structural panels fitted to the roof of a building;

[0126] FIG. 10 shows the use of structural panels applied to a roof or outer surface of a building for protection (such as hurricane or storm protection);

[0127] FIG. 11 shows the use of structural panels on a roof of a building;

[0128] FIG. 12A shows roof tile configured from a structural panel;

[0129] FIG. 12B shows an alternative roof tile; and

[0130] FIG. 13 shows corrugated roofing sheets configured from the structural panel.

[0131] In the drawings, like parts are denoted by like reference numerals. The drawings are not drawn to scale.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0132] Structural Panel

[0133] A perspective view of a structural panel is shown in FIG. 1. The structural panel can be configured for use in various applications, as outlined below.

[0134] The structural panel of FIG. 1 comprises a laminated structure of two planar layers. A first layer 10 comprises a sheet of a self-reinforced polyolefin material. In FIG. 1, this material is self-reinforced polypropylene (srPP), but other self-reinforced polyolefins (such as self-reinforced polyethylene) could be used.

[0135] The first layer 10 is arranged on top of or adjacent a second layer 12 comprising a polymer foam. In this case the polymer foam is expanded polypropylene with a density of between 30 to 90 grams per litre.

[0136] The first 10 and second 12 layer are bonded or secured together, to form a panel 100. The panel is semi-rigid. Advantageously, the self-reinforced polyolefin layer is robust and offers significant protection from impacts. Furthermore, the polymer foam layer is resilient and can absorb the energy of such impacts. Together, the structural panel provides a hard wearing and lightweight impact protection panel or sheet, which can be formed into various applications.

[0137] FIG. 2 shows a perspective view of a further embodiment of the structural panel 200. The panel of FIG. 2 comprises the self-reinforced polyolefin layer 10 and the polymer foam layer 12 described above with respect to FIG. 1. However, the structural panel of FIG. 2 further comprises a vinyl layer 14, on top of and bonded to the self-reinforced polyolefin layer 10. In other words, the self-reinforced polyolefin layer 10 is sandwiched between the vinyl layer 14 and the polymer foam layer 12.

[0138] The vinyl layer 14 is impregnated with ink. The vinyl layer may include printed text, colours or images. For instance, warning signs or text may be printed on the vinyl layer. The vinyl layer may provide a waterproofing layer.

[0139] The structural panel 200 of FIG. 2 also includes a fire retardant layer 16 bonded to the polymer foam layer 12. In other words, the polymer foam layer 12 is sandwiched between the fire retardant layer 16 and the self-reinforced polyolefin layer 10.

[0140] FIG. 3 shows a perspective view of the structural panel 300, having the laminated structure of the panel in FIG. 1. Here, the first 10 and second 12 layers of the panel have been bonded by application of heat to localised areas 18 at the structural panel. The heat may be applied to localised areas 18 by application of a hot iron or rod to portions of the surface of the structural panel 300. This can melt the localised portions 18 of the self-reinforced polyolefin layer 10 and the polymer foam layer 12 to bond the two layers in the localised regions 18. Bonding the layers only in localised areas is sufficient to securely fasten the layers of the laminated material together, but without disrupting the fibres of the self-reinforced material.

[0141] Although the localised areas 18 are shown as distributed across the surface of the structural sheet 300 in FIG. 3, it will be understood that any number of bonded regions may be provided, with any distribution, spacing or patterning across the planar area of the panel.

[0142] FIG. 4 shows an alternative embodiment, in which the first 10 and second 12 layers of the laminated structure are bonded at the perimeter of the structural panel 400. Again, the bonding is achieved by heating a strip or border 20 at the edge or perimeter of the panel, in order to melt only these portions of the laminated layers in order to be fused together (as shown by fused region 22).

[0143] Impact Proof Panels, Door and Window Shutters and Window Protection Made from Self-Reinforced Polyolefins.

[0144] Self-reinforced polyolefin panels (comprising, for example, srPP (self-reinforced polypropylene) or srPET (self-reinforced polyethylene)) can be utilised to make impact proof panels for use in building protection such as hurricane protection or flying debris protection such as European seaside window protection. In addition, it can be deployed in certain areas of buildings, such as stable doors to protect from other impacts such as horse's hooves, or in barns where animals can cause damage to wooden structures.

[0145] The srPP or srPET can be used alone or in combination with EPP (expanded polypropylene) or similar foam substrate whereby the addition of EPP softens the transmission of force through the combined material thereby absorbing the impact force and protecting the item below. Such an example might include a very lightweight window covering for storm protection over windows near shingle beaches, or temporary spectator protection at events where there is flying debris such as rally events.

[0146] The combination of a srPP/srPET layer over EPP and then another srPP/srPET layer can at certain configuration absorb significant impact from example shotgun pellets or shrapnel and can provide such protection that can quickly be erected due to its very lightweight properties.

[0147] An example of such would be the construction of military field fencing or kit buildings that can be erected quickly at a military camp offering protection from shrapnel, a low radar footprint due to the plastic materials used, and also having EPP gives insulation benefits to humans in the case of field buildings in military or emergency use such as aid hospitals. The panels can be easily pre-cut to patterns and assembled using a means of coupling. They will be resistant to rot and rust due to the polypropylene construction and end of life recyclable.

[0148] FIG. 5 shows a srPP/srPET sheet manufactured to make a window frame and window louvres (window shutter), instead of wood. This is beneficial to ‘weather proof’ a building, for instance.

[0149] The window shutter 500 of FIG. 5 includes a frame formed of struts 510 each configured from a structural panel as discussed above. The window shutter further comprises slats 512, each formed from a structural panel as discussed above. The slats 512 are arranged in the frame to provide a protective barrier to be placed in front of a window 518. In this case, the slats 512 are arranged spaced apart in the frame such that the plane of each slat is at an approximately 45° angle to the plane of the shutter frame. This allows some light to pass through the shutter, even when the shutter is arranged over the window. However, this arrangement of the slats also provides protection to the window from impacting missiles, projectiles or flying debris.

[0150] The shutter 500 of FIG. 5 further comprises a hinge 514 to hingedly connect the frame of the shutter to a window frame or building. In this way, the shutter may be fixed to a building, and arranged in an opened or closed position. The shutter 500 of FIG. 5 further includes a fastener 516, for holding or maintaining the shutter in an open or closed position.

[0151] In an alternative example, each of the slats and struts described with respect to the window shutter in FIG. 5 could be provided without use of polymer foam. In other words, the slats and struts may be formed of a self-reinforced polyolefin material only, or in combination with other materials.

[0152] FIG. 6 shows a srPP or srPET roller shutter 600. Thus, FIG. 6 shows an example of a roller shutter comprising self-reinforced polyolefin material. The roller shutter may comprise slats 612, each hingedly fixed to each other as described below with respect to FIG. 7. Each slat 612 may be formed of a structural panel or sheet as described above. The shutter may include a manual or automated roller mechanism 614. Again, this shutter can be used for protection and/or weather proofing of a building.

[0153] In an alternative example, each of the slats described with respect to the shutter in FIG. 6 could be provided without use of polymer foam. In other words, the slats may be formed of a self-reinforced polyolefin material only, or in combination with other materials.

[0154] FIG. 7 shows a possible structure for a protective shutter or blind. In particular, the structure shown in FIG. 7 may be use to provide the roller style shutter of FIG. 6.

[0155] As shown in FIG. 7, a plurality of slats or battens 710, 712 each formed from the structural sheet described above may be hingedly connected to form a shutter layer, sheet or panel. In particular, each slat 710, 712 is formed from a layer of polymer foam 714 (here, expanded polypropylene or similar) sandwiched between two layers of self-reinforced polyolefin 716, 718 (here, self-reinforced polypropylene). Within each slat, the layers are bonded by provision of a fastener 720 (such as a stich, rivet or glue). However, application of heat and pressure could instead be used to bond the layers of the slat 710, 712.

[0156] The plurality of slats 710, 712 may be connected by a hinged joint 722. The hinged joint 722 may be provided by use of webbing fabric or self-reinforced polyolefin material to join the slats 710, 712. As such, the slats can be folded or concertinaed with respect to each other. This allows the shutter panel (comprising a plurality of slats) to be rolled or folded for storage.

[0157] In an alternative example, each of the slats described with respect to the shutter in FIG. 7 could be provided without use of polymer foam. In other words, the slats may be formed of a self-reinforced polyolefin material only, or in combination with other materials.

[0158] Fencings, Barriers or Hoardings Made from Self-Reinforced Polyolefins

[0159] Protective barriers formed of srPP, or a combination of srPP with srPET or EPP could also be formed. These applications may make use of layers of srPP that are 3 mm thick or more. The barriers could be flexible, and arranged upon a mounting frame, or could incorporate a thickness of srPP such that the barriers are rigid or semi-rigid.

[0160] Similarly, advertising hoardings or panels could be formed from srPP. Said hoardings may comprise a sheet of srPP alone, or in combination with other materials such as EPP or srPET. An image may be printed on the srPP layer, or otherwise incorporated into the hoarding (including a printed layer, laminated with the srPP layer any further layer (such as srPET or EPP).

[0161] Advantageously, said protective barriers or advertising hoardings are robust and can withstand heard wear from weather etc. Furthermore, the barriers and hoarding scan provide protection (for instance, from shrapnel or bullets) to persons behind or enclosed by said barrier or hoardings.

[0162] FIG. 8 shows field fencing or protective barriers 810, 820 formed of structural panels. The field fencing or protective barrier panels 810, 820 formed may be formed using a layered structure including a self-reinforced polyolefin (e.g. srPP, srPET or a combination of the two materials). The fencing or protective barrier panels 810, 820 formed may be formed according to the structural panels described above. The fencing or protective barrier panels 810, 820 may further comprise a stand or foot, to allow the panels to be arranged in an upright position.

[0163] The barriers can provide protection from shrapnel, bullets, or missiles or as protection from other impacts from blast or flying debris etc. A printed layer (for example, a printed vinyl layer or similar) may be applied to an outer side 840 of the described protective barrier to provide camouflage, advertising hoardings or information boards. Said hoarding and barriers are robust and weatherproof. Said hoardings could be used as robust and secure fencing, or for military protective purposes.

[0164] Each structural panel (configured as a fencing panel or hoarding 810, 820) may comprise one or more hinges. In this way, an otherwise flat panel can be bent or folded at the hinge. Thus, the hoardings or fending can be bent to fit around a required area or object, or can be folded for storage.

[0165] In an alternative example, each of the panels described with respect to the fencing or barriers in FIG. 8 could be provided without use of polymer foam. In other words, the panels may be formed of a self-reinforced polyolefin material only, or in combination with other materials.

[0166] Roofing Panels or Roof Tiles

[0167] Panels of srPP or srPET (or a combination) can be used, for instance together with traditional roofing materials and techniques, to reinforce rooves in geographical areas prone to hurricanes, typhoons and other extreme weather (including hail storms, heavy snow etc.). For instance, a srPP or srPET layer (in some examples, in combination with other materials such as EPP, srPET etc.) can be arranged underneath or over the top of traditional roof tiles, roof felt etc. The srPP or srPET panels can be permanently fixed within the traditional roofing structure, to provide long term protection.

[0168] In a still further embodiment, a plurality of srPP panels (in some examples, in combination with other materials such as EPP, srPET etc.) can be arranged for use as roof tiles. For instance, said srPP tiles can be arranged to be covering a roof in the manner of traditional roof tiles.

[0169] FIG. 9 shows the use of panels or sheets of srPP, or srPP and ePP, fitted to the roof 910 of a building. Each panel or sheet 900 may be a structural sheet or panel as described above. In a specific example, each structural sheet 900 comprises a self-reinforced polyolefin layer of self-reinforced polypropylene and/or of srPET 912. The structural sheet further comprises a layer of polymer foam (here, ePP) 914.

[0170] Each roofing panel or sheet may be battened, glued or nailed to the roof base or structure. A traditional roof base or structure can be used, without modification.

[0171] In an alternative example, each of the panels described with respect to the roofing panels in FIG. 9 could be provided without use of polymer foam. In other words, the panels may be formed of a self-reinforced polyolefin material only, or in combination with other materials.

[0172] FIG. 10 shows the use of structural sheets or panels 1000 (for example, comprising srPP, srPP/ePP, or srPP/ePP/srPP laminated layers), which could be applied to a roof or outer surface of a building for protection. For example, such panels could be applied to the outer surfaces of a building upon receipt of a severe weather warning, to protect the building from flying debris as a result of a hurricane, typhoon etc.

[0173] The panels include further battens 1012 of wood and/or of srPP to secure and reinforce the panels 1000. The battens increase the stiffness and structural integrity of the panels. They can also be used as a fastener or connector of the panels to a building.

[0174] In an alternative example, each of the structural sheets or panels, or the battens described with respect to FIG. 10 could be provided without use of polymer foam. In other words, the panels or battens may be formed of a self-reinforced polyolefin material only, or in combination with other materials.

[0175] FIG. 11 shows the use of structural panels (comprising srPP or srPP/ePP) as a protection layer 1110 on a roof of a building. The protection layer (and/or battens) 1110 can be those described above with respect to FIG. 6. Alternatively, the protective layer 1110 can be a flexible layer of self-reinforced polyolefin, formed in the manner of a membrane or tarpaulin.

[0176] The layers can be applied to a standard or traditional roof base construction 1112, and topped with tiles or roof shingles 1114. Said tiles or roof shingles may also comprise srPP. Alternatively, said tiles or roof shingles can be of a traditional design. The roof tiles or shingles may be pegged to nailed to battens 1116. The battens may be formed of a self-reinforced polyolefin.

[0177] FIG. 12A shows a roof tile or shingle 1200 formed as a structural panel as described above. Specifically, the roof tile comprises a layered structure of srPP/srPET 1210 and ePP 1212. FIG. 12B shows an alternative roof tile 1250 formed of a layer of a self-reinforced polyolefin (e.g. srPP) only.

[0178] FIG. 13 shows a corrugated sheet 1300, configured from a structural sheet as described above. Specifically, FIG. 13 shows a corrugated roofing sheet comprising srPP, srPET or a combination of these materials. Ideally the corrugated sheets are comprised of multiple layers of these materials, and are shaped or formed in the corrugated structure. The corrugated structure may further strengthen or increase the rigidity of the panel. As an example, the roof tile, fencing panels or shutter panels described above could be formed from the corrugated sheet. In an alternative example, the corrugated sheet in FIG. 13 could be provided without use of polymer foam. In other words, the corrugated sheet may be formed of a self-reinforced polyolefin material only, or in combination with other materials.

[0179] As will be appreciated by the skilled person, details of the above embodiment may be varied without departing from the scope of the present invention, as defined by the appended claims.

[0180] Many combinations, modifications, or alterations to the features of the above embodiments will be readily apparent to the skilled person and are intended to form part of the invention. Any of the features described specifically relating to one embodiment or example may be used in any other embodiment by making the appropriate changes.