Articles of composite construction and methods of manufacture thereof

Abstract

An article manufactured in a mould and which comprises a structural composite of plastics layers, the article having a wall defining an internal space for holding contents therein; wherein, the wall is formed from at least two layers of plastics materials; wherein a first of said layers comprises a thermoplastics material and at least a second layer comprises a thermosetting resin and a fibrous layer.

1 - 72 . (canceled) 
     
     
         73 . A storage vessel manufactured in a rotational mould and which comprises a structural composite including a thermoplastics material and a fibrous reinforcing layer, the vessel when formed having a wall defining an internal space for holding contents therein;
 the wall including said thermoplastics material and the fibrous reinforcing layer at least partially embedded in said thermoplastic material and reinforcing the composite;   wherein the vessel is manufactured in the rotational mould according to the following method steps;   a) placing the layer of fibrous material inside the mould in apposition to an inner surface of the mould;   b) placing the thermoplastics material inside the mould;   c) closing the mould and heating the mould to thereby heat the thermoplastics material sufficient to enable the thermoplastics material to morph from a non flowable state to a flowable state;   d) during rotation of the mould, allowing the heated thermoplastics material to flow at least part way through the thickness of the layer of fibrous reinforcing material so that at least some fibres of the fibrous layer are embedded in the thermoplastics material thereby forming a layer of reinforced thermoplastics material;   e) allowing the thermoplastics layer to cool; and   f) removing the composite from the rotational mould.   
     
     
         74 . A vessel according to  claim 73  wherein the thermoplastics layer material is selected from any one of the following materials; polyethylene (HDPE), polypropylene (PP), polyvinylidene fluoride (PVDF), ethylene chloro tri fluoro ethylene (ECTFE). 
     
     
         75 . A vessel according to  claim 74  wherein the fibrous layer material is selected from a group including woven cloth, mat or felt. 
     
     
         76 . A vessel according to  claim 75  wherein the fibrous layer comprises woven cloth having alternate strands of warp and weft traversing the thickness of the cloth. 
     
     
         77 . A vessel according to  claim 76  wherein the thermoplastic layer material is introduced into the mould in powder form prior to heating. 
     
     
         78 . A vessel according to  claim 77  wherein the fibrous layer is prior to introduction into said mould pretreated with a primer wherein the primer is a wetting binder solution including a solvent which evaporates before closing the mould. 
     
     
         79 . A vessel according to  claim 78  wherein the binder is polystyrene or polymethylmethacrylate dissolved in their respective monomers styrene and methyl methacrylate as the solvent. 
     
     
         80 . A vessel according to  claim 79  wherein the thermoplastics material is urged into engagement with the fibre reinforcing layer under gas pressure applied inside the mould. 
     
     
         81 . A vessel according to  claim 80  wherein the gas pressure is adjusted according to the degree of penetration of the thermoplastics material through the fibrous layer required. 
     
     
         82 . A vessel according to  claim 81  wherein the gas pressure is applied to enable full penetration of the thermoplastics layer through the fibre reinforcing layer. 
     
     
         83 . A vessel according to  claim 82  wherein the gas pressure is applied to enable partial penetration of the thermoplastics layer through the fibre reinforcing layer. 
     
     
         84 . A vessel according to  claim 83  wherein a thermosetting resin is applied to fibres of the fibrous layer not embedded in the thermoplastics layer to thereby form a bond between the thermoplastics layer and the thermosetting resin. 
     
     
         85 . A vessel according to  claim 84  wherein thermosetting resin is, selected from a group including polyester, vinylester, epoxy and polyurethane. 
     
     
         86 . A vessel according to  claim 85  wherein the vessel forms a hollow liquid storage tank mountable on a road tanker vehicle. 
     
     
         87 . A vessel according to  claim 85  wherein the vessel forms an aircraft fuel tank. 
     
     
         88 . A vessel according to  claim 85  wherein the article forms a hollow storage vessel for a rail car. 
     
     
         89 . A vessel according to  claim 78  wherein the primer applied to the fibrous layer increases the penetrability of the thermoplastics material into said fibres during rotation of said mould. 
     
     
         90 . A vessel according to  claim 89  wherein the primer comprises polystyrene dissolved in styrene. 
     
     
         91 . A vessel according to  claim 90  wherein the primer is mixed with a suspension of thermoplastics powder. 
     
     
         92 . A method of manufacture of a composite hollow vessel using a rotational mould, the method comprising the steps of:
 a) taking a fibrous layer of material and placing the material against an inner surface of a mould having a predetermined internal shape;   b) forming a the fibrous layer into a shape conforming with the mould;   c) introducing a thermoplastics material into the mould and heating the material;   d) allowing the thermoplastics material to at least partially penetrate the fibrous layer;   e) heating the thermoplastics material sufficient to enable that material to morph from a solid to a flowable state;   f) allowing the thermoplastics material to flow at least part way through the thickness of the at least one fibrous layer to form a wall of an article to be formed in the mould;   g) allowing the thermoplastics material to cool so that at least some fibres of the at least one fibrous layer are embedded in the first layer; and   h) removing the article from the mould.   
     
     
         93 . A method of manufacture according to  claim 92  wherein the thermoplastic layer is melted about the fibrous layer causing it to flow at least part way through the thickness of the fibrous layer. 
     
     
         94 . A method according to  claim 93  wherein, the thermoplastics layer material is selected from the following materials polyethylene (HDPE), polypropylene (PP), polyvinylidene fluoride (PVDF), ethylene chloro tri fluoro ethylene (ECTFE). 
     
     
         95 . A method according to  claim 94  wherein, the fibrous layer material is selected from a group including woven cloth, mat or felt. 
     
     
         96 . A method of manufacture according to  claim 95  comprising the further step of applying a primer as a wetting binder solution applied to said fibrous layer and including a solvent which evaporates before closing the mould. 
     
     
         97 . A method of manufacture according to  claim 96  wherein, the binder is polystyrene or polymethylmethacrylate dissolved in their respective monomers styrene and methyl methacrylate as the solvent. 
     
     
         98 . A method according to  claim 97  comprising the preliminary step of applying a release agent to the mould inner surface prior introduction of the fibrous layer. 
     
     
         99 . A method according to  claim 98  comprising the further step of urging the thermoplastics material into engagement with the fibre reinforcing layer under gas pressure applied inside the mould. 
     
     
         100 . A method according to  claim 99  wherein the gas pressure is adjusted according to the degree of penetration of the thermoplastics material through the fibrous layer required. 
     
     
         101 . A method according to  claim 100  wherein the gas pressure is applied to enable full penetration of the thermoplastics layer through the fibre reinforcing layer. 
     
     
         102 . A method according to  claim 100  wherein the gas pressure is applied to enable partial penetration of the thermoplastics layer through the fibre reinforcing layer. 
     
     
         103 . A method according to  claim 102  wherein a thermosetting resin is applied to fibres of the fibrous layer not embedded in the thermoplastics layer to thereby form a bond between the thermoplastics layer and the thermosetting resin. 
     
     
         104 . A method according to  claim 103  wherein thermosetting resin is, selected from a group including polyester, vinylester, epoxy and polyurethane. 
     
     
         105 . A method according to  claim 104  wherein the composite element forms a hollow storage vessel.