Impact-protection barrier with reinforced rails and method for making same

Abstract

Impact protection barriers having increased resistance to damage from impact events include posts and rails mounted onto and supported by the posts. The rails are reinforced with a layer of a nonwoven fabric and a layer of a polyurethane elastomer covering the nonwoven fabric layer. The reinforcement may be applied to the rails of previously-constructed protection barriers; alternatively the reinforced rails can be produced and then mounted on to the posts to produce the impact protection barrier.

Description

Atty Ref.: 157928.221088-WO (86147)IMPACT-PROTECTION BARRIER WITH REINFORCED RAILS AND METHOD FOR MAKING SAMECROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and all advantages of U.S. Provisional Patent Application No. 63 / 681 ,205 filed on 09 August 2024, the content of which is incorporated herein by reference.FIELD OF THE INVENTION

[0002] This invention relates to protection barriers such as fencing, vehicle barriers, railings and the like.

[0003] Barriers are erected in many places for purposes of safety (guardrails, handrails) and controlling and / or assisting both pedestrian and vehicular traffic. A common type is a post-and- rail construction, in which vertical posts are erected and rails are mounted onto and between the posts. Although the posts and rails can be made from a wide variety of materials, it is often beneficial for cost, aesthetic or other reasons to use wood railings. Other materials of construction include, for example, various sorts of thermoplastic or thermoset resins, steel or other metal, and engineered (laminated) wood products.

[0004] These barriers are frequently subjected to impact events. A typical impact event occurs when a moving vehicle makes contact with the rails, although other types of impacts involving other objects (including people and other animals) do occur. The rails need to absorb the energy of the impact and stop or at least slow the progress of the moving vehicle or other object impacting the barrier.

[0005] The rails should be resistant to damage from these impact events, at least low-speed impact events as are commonly experienced in settings such as parking lots and pedestrian control or assistance. Railings made from brittle, highly rigid materials can crack and deform. More flexible railings such as wood and certain plastics can absorb energy by bending upon impact, but even these materials are prone to damage. Wood, particularly the inexpensive, rather low-quality grades that are typically used as railings, can easily crack even upon low-speed impact.

[0006] There is, therefore, a desire for improved barriers and for a method to increase the impact resistance of the railings. In particular, a method to improve the impact resistance of wood railings is wanted. It would be especially beneficial if such a method were easily adapted for application in the field, to retrofit pre-existing barriers to improve their impact performance.BRIEF SUMMARY

[0007] Disclosed is an impact protection barrier comprising a pair of posts and one or more reinforced rails mounted onto and supported by the pair of posts, wherein the reinforced rails comprise:Atty Ref.: 157928.221088-WO (86147) a) a rail core, the rail core having a longitudinal extension in an axial direction, the longitudinal extension of the rail core having an outer surface; b) a nonwoven fabric layer applied directly or indirectly onto and substantially covering the outer surface of the longitudinal extension of the rail core; and c) a polyurethane elastomer layer substantially covering the nonwoven fabric layer.

[0008] Also disclosed is a method of making an impact protection barrier of the invention, the comprising:A) producing a reinforced rail by i) applying a nonwoven fabric directly or indirectly onto an outer surface of a longitudinal extension of a rail core to form a nonwoven fabric layer that substantially covers the outer surface of said longitudinal extension of the rail core; ii) applying a polyurethane-forming reaction mixture onto the nonwoven fabric layer such that the polyurethane-forming reaction mixture substantially covers the applied non-woven fabric layer; and iii) curing the polyurethane-forming reaction mixture to produce a polyurethane elastomer layer substantially covering the nonwoven fabric layer and produce the reinforced rail; andB) mounting the reinforced rail onto a pair of posts to produce the protection barrier.

[0009] In addition, a second method of making an impact protection barrier of the first aspect is disclosed, the second method comprising1) applying a nonwoven fabric directly or indirectly onto an outer surface of a longitudinal extension of the rail core, the rail core being mounted onto a pair of posts such that the rail core is supported by the pair of posts, to form a nonwoven fabric layer that substantially covers the outer surface of the longitudinal extension of the rail core;2) applying a polyurethane-forming reaction mixture onto the nonwoven fabric layer such that the polyurethane-forming reaction mixture substantially covers the applied non-woven fabric layer, and3) curing the polyurethane-forming reaction mixture to produce a polyurethane elastomer layer substantially covering the nonwoven fabric layer and produce the reinforced rail mounted onto and supported by the posts.

[0010] The reinforced rails of the impact protection barrier have greater resistance to damage due to impact events than do the rail cores by themselves.DESCRIPTION OF DRAWINGS

[0011] Figure 1 is a front view of an embodiment of an impact protection barrier of the invention.

[0012] Figure 2 is a front view, partially in section, of an embodiment of a reinforced rail for use in the impact protection barrier of the invention.Atty Ref.: 157928.221088-WO (86147)

[0013] Figure 3 is a cross-sectional view, taken along lines 3-3 of Figure 2, of the reinforced rail shown in Figure 2.

[0014] Figure 4 is a front view, partially in section, of a second embodiment of a reinforced rail for use in the impact protection barrier of the invention.

[0015] Figure 5 is a cross-sectional view, taken along lines 5-5 of Figure 4, of the reinforced rail shown in Figure 4.DETAILED DESCRIPTION

[0016] Turning to Figure 1, impact protection barrier 1 comprises generally vertical posts 10. As shown, reinforced rails 7 are mounted generally horizontally onto and are supported by posts 10, each rail being mounted onto and supported by a successive pair of posts 10. The number of reinforced rails 7 between each successive pair of posts 10 is arbitrarily shown as three in Figure 1; any lesser or greater number of reinforced rails may be mounted between each successive pair of posts 10. Similarly, the number of posts 10 is arbitrarily shown as three; the impact protection barrier may comprise as few as two posts 10 or any greater number of posts 10, with reinforced rails 7 being mounted on and supported by successive pairs of posts 10.

[0017] Turning now to Figures 2-5, each reinforced rail 7 comprises a rail core 2, which is a structural element stiff enough to bear its own weight without sagging when mounted horizontally between posts. The material of construction maybe be, for example, natural wood; an engineered wood such as a wood laminate; a metal such as steel or aluminum; an organic polymer, which may be reinforced; and the like. Rail core 2 may be a composite material of various types; such a composite may have a core-shell or other convenient construction. Wood, especially natural wood, is a material of construction of particular interest for the rail core.

[0018] Rail core 2 may be solid or hollow in the longitudinal direction. It may be linear or curved or angled along its longitudinal extension. Its cross-section may be circular, polygonal, elliptical or other convenient geometry. The cross-sectional shape and / or area may be constant or vary along the longitudinal extension of the rail core.

[0019] Rail core 2 has a longitudinal extension in an axial direction, as indicated by doubleheaded arrow A in each of Figures 2 and 4. The longitudinal extension of the rail core has an outer surface 11 (Figures 2-5).

[0020] Nonwoven fabric layer 3 is applied directly or indirectly onto and substantially covers outer surface 11 of the longitudinal extension of rail core 2. By “directly”, it is meant that nonwoven fabric layer 3 is applied onto outer surface 11 of the longitudinal extension of rail core 2 without any intervening layer interposed between outer surface 11 and nonwoven fabric layer 3. By “indirectly”, it is meant that one or more intervening layers (such as are described below, for example) are present between outer surface 11 and nonwoven fabric layer 3. If desired, outer surface 11 may be subjected to preparatory steps such as cleaning and / or abrading to removeAtty Ref.: 157928.221088-WO (86147) contamination and / or protrusions, drying to remove surface moisture, and treatment such as plasma or corona treatment or application of a primer to improve adhesion, before applying nonwoven fabric layer 3 or any preliminary polyurethane elastomer layer 9 (see Figures 3 and 5).

[0021] Nonwoven fabric layer 3 “substantially” covers outer surface 11 of the longitudinal extension of rail core 2 if it covers at least 90% of the area thereof, not including the area of sections (such as at the ends of rail core 2) where rail core 2 is mounted onto posts 10. Small openings in applied non-woven fabric layer 3 may exist, for example, at seams where edges of nonwoven fabric meet. Non-woven fabric layer 3 may or may not cover points (such as the ends) along the longitudinal extension (if any) of rail core 2 where, for example, rail core 2 is mounted onto posts 10.

[0022] The nonwoven fabric is a textile comprising fibers that are formed into a textile by entangling fibers or filaments mechanically, thermally and / or chemically, or by fabricating a film. The fibers are not woven, knitted or otherwise knotted. The nonwoven fabric may be produced from fibers or filaments by, for example, processes such as felting, hydroentanglement, needle punching, stitching, spunbonding, melt blowing, wet-laying, air-laying and carding / crosslapping. Alternatively, nonwoven fabric may be produced from film using methods such as fibrillating, serration, perforating, or vacuum-forming with patterned holes.

[0023] The material of construction of the nonwoven fabric may vary considerably. Suitable materials of construction include, for example, mineral fibers such as mineral wool and glass fibers; fibers from plant and animal sources such as cotton, linen, hemp, jute and coir; and synthetic polymers such as rayon, polyolefin (such as polyethylene and polypropylene), polyester (such as polyethylene terephthalate and polylactide), regenerated cellulose, aramid and polyamide, including blends. Specific examples of nonwoven fabric include geotextiles such as are available from, for example, US Fabrics, WINFAB Industrial Fabrics, Voda-Land USA, as well as many others.

[0024] The nonwoven fabric may be provided in sheet or tape form, or other convenient configuration. It may be applied by wrapping a sheet or tape around the outer surface of the longitudinal extension of the rail core. Nonwoven fabric layer 3 may comprise multiple pieces that meet or overlap at seams. Nonwoven fabric layer 3 may comprise a single ply or multiple plies.

[0025] Nonwoven fabric layer 3 may have a thickness of, for example, 0.05 to 2 mm. Its thickness may be at least 0.1 mm or at least 0.15 mm and may be at most 1.5 mm, at most 1 mm or at most 0.5 mm. Nonwoven fabric layer 3 may have an areal weight of, for example, 50 to 1700 g / m2. The areal weight in specific embodiments may be at least 75 g / m2, at least 125 g / m2or at least 200 g / m2, and may be up to 1000 g / m2, up to 750 g / m2or up to 500 g / m2.Atty Ref.: 157928.221088-WO (86147)

[0026] Polyurethane elastomer layer 4 substantially covers nonwoven fabric layer 3. By “substantially” in this context it is meant polyurethane elastomer 4 covers at least 90% of the outer surface of nonwoven fabric layer 3. Small gaps or openings in polyurethane elastomer 4 may be present. Polyurethane elastomer 4 typically covers at least 95% or at least 98% of the exposed outer surface of nonwoven fabric layer 3. Polyurethane elastomer layer 4 forms a layer on top of nonwoven fabric layer 3. The thickness of the layer of polyurethane elastomer layer 4 may be, for example 0.25 to 10 mm, as measured from the outer surface of nonwoven fabric layer 3. In specific embodiments the thickness of polyurethane elastomer layer 4 may be at least 0.5 mm or at least 0.75 mm, and may be up to 5 mm, up to 3 mm or up to 2 mm.

[0027] Polyurethane elastomer layer 4 may penetrate into nonwoven fabric layer 3, either partially or entirely through the thickness of nonwoven fabric layer 3.

[0028] The polyurethane elastomer that constitutes polyurethane elastomer layer 4 may exhibit an elongation to break of at least 10%, alternatively at least 25% or at least 50%, as measured according to ASTM D3754-17. The elongation to break may be as much as 500% or as much as 250%. Polyurethane elastomer 4 may exhibit a Shore D hardness of at most 65D, alternatively at most 50D, especially 20D to 40D as measured according to ASTM D2240. Polyurethane elastomer layer 4 may have a density of 0.8 to 1.5 g / cc.

[0029] Polyurethane elastomer layer 4 is conveniently formed by applying a polyurethane- forming reaction mixture onto the applied nonwoven fabric 3 such that the polyurethane-forming reaction mixture substantially covers applied nonwoven fabric 3, and the curing the polyurethane- forming reaction mixture. The reaction mixture is a fluid that can be applied using methods such as spraying, brushing, dipping, immersion or rolling. Spraying is an especially useful method for applying the reaction mixture.

[0030] The polyurethane-forming reaction mixture comprises at least one organic polyisocyanate and at least one polyol that has a hydroxyl number of 15 to 225 mg KOH / g as measured according to ASTM D6342-22.

[0031] The organic polyisocyanate in certain embodiments has an isocyanate equivalent weight of up to 500 g / equivalent, alternatively up to 400 g / equivalent, alternatively 80 to 400 g / equivalent and in some embodiments 125 to 400 g / equivalent, as measured according to ISO 14896 / 3. Examples of useful organic polyisocyanates include m-phenylene diisocyanate, toluene-2,4- diisocyanate, toluene-2,6-diisocyanate, hexamethylene- 1 ,6-diisocyanate, tetramethylene- 1 ,4- diisocyanate, cyclohexane- 1 ,4-diisocyanate, hexahydrotoluene diisocyanate, naphthylene- 1,5- diisocyanate, 1,3- and / or 1 ,4-bis(isocyanatomethyl)cyclohexane (including cis- and / or trans isomers) methoxyphenyl-2,4-diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4’-diisocyanate, hydrogenated diphenylmethane-4,4’-diisocyanate, hydrogenated diphenylmethane-2,4’-diisocyanate, 4,4'-biphenylene diisocyanate, 3,3'-Atty Ref.: 157928.221088-WO (86147) dimethoxy-4,4'-biphenyl diisocyanate, 3,3'-dimethyl-4-4'-biphenyl diisocyanate, 3,3'- dimethyldiphenyl methane-4,4'-diisocyanate, 4,4',4"-triphenyl methane triisocyanate, a polymethylene polyphenylisocyanate (PMDI), toluene-2,4,6-triisocyanate and 4,4'- dimethyldiphenylmethane-2,2',5,5'-tetraisocyanate. In specific embodiments, the polyisocyanate comprises, alternatively is, diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'- diisocyanate, PMDI, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate or mixtures thereof. Diphenylmethane-4,4’-diisocyanate, diphenylmethane-2,4’-diisocyanate and mixtures thereof are generically referred to as MDI, and all can be used. Toluene-2,4-diisocyanate, toluene-2,6- diisocyanate and mixtures thereof are generically referred to as TDI, and all can be used. Any of the foregoing may be modified to produce poly isocyanate products that contain, for example, urea, urethane, carbodiimide, biuret, uretonimine or other linkages

[0032] Suitable organic polyisocyanates also include urethane group-containing, isocyanate- terminated prepolymers made by reacting an excess of any one or more of the foregoing polyisocyanates with a polyol. Such a prepolymer may have an isocyanate equivalent weight of, for example, 100 to 1000 g / equivalent.

[0033] The polyol that has a hydroxyl number of 15 to 225 mg KOH / g may be, for example, a polyether polyol, a polyester polyol, a poly(butadiene) polyol and / or a polyacrylate polyol. Polyether polyols are the most typical types. A polyether polyol may be, for example, a homopolymer of propylene oxide, a random and / or block copolymer of propylene oxide and ethylene oxide, a polymer or copolymer of 1,2- and / or 2,3-butylene oxide, or a polymer or copolymer of tetrahydrofuran.

[0034] The polyol that has a hydroxyl number of 15 to 225 mg KOH / g may have a nominal functionality of 2 to 6, especially 2 to 4 hydroxyl groups per molecule. The nominal functionality of a polyether polyol is the average number of hydroxyl groups of the starter compound used in manufacturing the polyether.

[0035] The polyol that has a hydroxyl number of 15 to 225 mg KOH / g may contain dispersed polymer particles such as polyurea, polyisocyanate, polyhydrazide, polystyrene, polyacrylonitrile, styrene-acrylonitrile and the like.

[0036] The polyol that has a hydroxyl number of 15 to 225 mg KOH / g may be or include a urethane group-containing, hydroxyl-terminated prepolymer made by reacting an excess of a polyol with a polyisocyanate.

[0037] The polyurethane-forming reaction mixture may be formulated to have a gel time of at least 20 seconds and up to 200 seconds, alternatively up to 100 seconds, at 23°C. Gel time is measured by mixing all components of the polyurethane-forming reaction mixture except the organic polyisocyanate in an open vessel such as a cup at 23°C, then mixing in the polyisocyanate at the same temperature. A metal or wooden spatula is then touched periodicallyAtty Ref.: 157928.221088-WO (86147) to the surface of the reaction mixture and pulled away. The gel time is the time after the polyisocyanate is mixed in at which the reaction mixture no longer adheres to the spatula when the spatula is pulled away. A gel time of at least 20 seconds is advantageous because it allows time for the reaction mixture to be formed and dispensed onto nonwoven fabric layer 3 and wet out at least the exposed surface of nonwoven fabric layer 3. Gel times greater than about 200 seconds are disadvantageous because longer processing times are needed.

[0038] Gel time can be adjusted by including a urethane catalyst, i.e., a catalyst for the reaction of a hydroxyl group with an isocyanate group, in the polyurethane-forming reaction mixture. Suitable catalysts include, for example, including tertiary amines, cyclic amidines, tertiary phosphines, various metal chelates, acid metal salts, strong bases, various metal alcoholates and phenolates and metal salts of organic acids. Catalysts of most importance are tertiary amine catalysts, cyclic amidines, and tin catalysts. Examples of tertiary amine catalysts include trimethylamine, triethylamine, N-methylmorpholine, N-ethylmorpholine, N,N- dimethylbenzylamine, N,N-dimethylethanolamine, N,N,N',N'-tetramethyl-1 ,4-butanediamine, N,N-dimethylpiperazine, 1 ,4-diazobicyclo-2,2,2-octane, bis(dimethylaminoethyl)ether, triethylenediamine and dimethylalkylamines where the alkyl group contains 4 to 18 carbon atoms. Mixtures of these tertiary amine catalysts are often used. Examples of tin catalysts are stannic chloride, stannous chloride, stannous octoate, stannous oleate, dimethyltin dilaurate, dibutyltin dilaurate, other tin compounds of the formula SnRn(OR)4-n, wherein R is alkyl or aryl and n is 0- 2, and the like.

[0039] Catalysts are typically used in small amounts, for example, each catalyst being employed from about 0.0015 to about 5% by weight of base polyether polyol.

[0040] The polyurethane-forming reaction mixture may also contain various optional ingredients. Among these are crosslinkers, i.e., compounds having at least three isocyanate-reactive groups and a hydroxyl number of at least 450 mg KOH / g, and chain extenders, i.e., compounds having exactly two isocyanate-reactive groups and a hydroxyl number of at least 450 mg KOH / g. The isocyanate-reactive groups are in certain embodiments hydroxyl and / or primary or secondary amino groups. Examples of crosslinkers and chain extenders include ethylene glycol, diethylene glycol, triethylene glycol, 1,3-propane diol, 1,2-propane diol, dipropylene glycol, tripropylene glycol, glycerin, trimethylolpropane, trimethylolethane, cyclohexane dimethanol, 1,4-butanediol, 1,2-butanediol, 1,3- butanediol, pentaerythritol, erythritol, sucrose, diethanolamine, triethanolamine, triisopropanolamine, diisopropanolamine, ethylene diamine, diethyltoluene diamine, dimethylthiotoluene diamine, toluene diamine, 1 ,2-propylene diamine and the like, as well as alkoxylates thereof having hydroxyl numbers of at least 450 mg KOH / g. Aromatic diamine chain extenders such as diethyltoluene diamine, dimethylthiotoluene diamine and toluene diamine are especially useful.Atty Ref.: 157928.221088-WO (86147)

[0041] The polyurethane-forming reaction mixture may further comprise one or more additional polyols having hydroxyl numbers of greater than 225 mg KOH / g and less than 450 mg KOH / g.

[0042] In addition to the foregoing components, the polyurethane-forming reaction mixture may contain various other optional ingredients such as fillers such as melamine and calcium carbonate; pigments and / or colorants such as titanium dioxide, iron oxide, chromium oxide, azo / diazo dyes, phthalocyanines, dioxazines and carbon black; reinforcing agents such as fiber glass, carbon fibers, flaked glass, mica, talc and the like; biocides; preservatives; antioxidants; flame retardants; surfactants; plasticizers; and the like.

[0043] A solvent or diluent may or may not be present in polyurethane-forming reaction mixture. Either or both of the isocyanate component and the polyol component may contain a solvent or diluent if desired, to adjust the viscosity to facilitate application or for other reasons.

[0044] In one method for applying the polyurethane-forming reaction mixture, the various components are brought together and combined in a mixer and then dispensed onto nonwoven fabric layer 3. Examples of suitable mixing equipment include high pressure impingement mixers and dynamic mixers that contain a turbine that spins at high speed. After mixing, the thus-formed polyurethane reaction mixture can be atomized by means of a high- pressure air stream injected at the outlet of the mixing device. The atomized mixture then can be sprayed onto nonwoven fabric layer 3. Certain of the components can be previously blended to form, for example, a formulated polyol component that is combined with the organic polyisocyanate in the mixer. The individual components or the reaction mixture may be heated if desired to, for example, to accelerate curing or adjust the viscosity of one or more of the components or the reaction mixture to facilitate application. The polyurethane-forming reaction mixture may be formed and dispensed at a temperature of, for example 10 to 80°C, especially 15 to 70°C or 20 to 70°C. These temperatures correspond to anticipated ambient temperature conditions for in-field application.

[0045] The polyurethane-forming reaction mixture is cured to produce the polyurethane elastomer substantially covering the nonwoven fabric and produce the reinforced rail. The polyurethane-forming reaction mixture may penetrate partially or entirely through the thickness of the nonwoven fabric before it cures. Curing typically occurs spontaneously when the polyurethane-forming reaction mixture is produced at temperatures as indicated above. It is generally unnecessary to apply heat to effect the cure, although it is within the scope of the invention to do so.

[0046] If desired, the steps of applying the nonwoven fabric and polyurethane elastomer can be repeated one or more times in alternating fashion to produce one or more successive layers of the nonwoven fabric and elastomer.Atty Ref.: 157928.221088-WO (86147)

[0047] Optionally, a layer of an adhesive may be applied to the outer surface of the longitudinal extension of the rail core prior to applying the nonwoven fabric. Such an adhesive may function to hold the nonwoven fabric in place temporarily until the polyurethane elastomer is applied.

[0048] A preliminary layer of polyurethane elastomer is optionally applied to the outer surface of the longitudinal extension of the rail core prior to applying the nonwoven fabric. Such a preliminary polyurethane elastomer layer may be as described above and may be applied and cured as described above. If desired, this preliminary polyurethane elastomer layer may function as an adhesive for the nonwoven fabric, by applying the fabric onto the preliminary polyurethane elastomer layer before it has fully cured, while it remains tacky. An embodiment of this type is shown in Figures 4 and 5. Reinforced rail 7 in Figures 4 and 5 includes rail core 2. Preliminary polyurethane elastomer layer 9 resides on the outer surface 11 of the longitudinal extension of rail core 2. Nonwoven fabric layer 3 covers the outer surface of preliminary polyurethane elastomer layer 9 and is optionally adhered thereto. Polyurethane elastomer layer 4 covers the outer surface of nonwoven fabric layer 3, optionally penetrating partially or entirely though the thickness of nonwoven fabric layer 3.

[0049] The method of the invention can be practiced on existing impact barriers that have the rails already installed onto the posts. In such a case, the existing rails serve as the rail cores. Alternatively, rail cores can be reinforced in accordance with the invention and thereafter mounted onto posts to form the impact protection barrier.

[0050] If desired, posts 10 also may be reinforced in like manner, in accordance with the invention.

[0051] The following example is provided to illustrate the invention but are not intended to limit the scope thereof. All parts and percentages are by weight unless otherwise indicated.

[0052] A polyurethane-forming reaction mixture having a gel time of 30-90 seconds is prepared by mixing a 343 isocyanate equivalent weight, urethane group-containing, isocyanate-term inated prepolymer of methylene diphenyl diisocyanate and a polypropylene oxide) diol combined with propylene carbonate as a diluent, a polyether polyol having a hydroxyl number of less than 225 mg KOH / g, an aromatic diamine chain extender and a urethane catalyst. A polyurethane elastomer made by curing this reaction mixture has a Shore D hardness of about 31 D and an elongation to break of over 50%. The reaction mixture is sprayed at room temperature onto one surface of an 8 mm plywood board to form a coating about 1 mm thick. While the reaction mixture is still tacky, a 0.3-mm thick nonwoven geotextile fabric is applied. Then, a second portion of the polyurethane-forming reaction mixture is sprayed on top of the nonwoven fabric and cured to produce a polyurethane elastomer layer 1.5-2 mm thick. The outer polyurethane elastomer layer penetrates partially but not entirely through the nonwoven fabric.Atty Ref.: 157928.221088-WO (86147)

[0053] The impact resistance of the thus-coated panels is evaluated using a Schmidt hammer (type N) operated to deliver 2.207 N impact energy. The hammer rebound is measured and the panel is visually inspected for damage. The rebound is 39 and 44 mm for two duplicate samples. No physical damage to either of the coated panels occurred.

[0054] For comparison, additional samples of the plywood are coated in the same manner, except the non-woven fabric is omitted. Upon testing with the Schmidt hammer, the rebound for three duplicate samples is only 28-31 mm, and in each case the applied coating is dented in the shape of the hammer head.

Claims

Atty Ref.: 157928.221088-WO (86147)CLAIMS1. An impact protection barrier comprising a pair of posts and one or more reinforced rails mounted onto and supported by the pair of posts, wherein the reinforced rails comprise: a) a rail core, the rail core having a longitudinal extension in an axial direction, the longitudinal extension of the rail core having an outer surface; b) a nonwoven fabric layer applied directly or indirectly onto and substantially covering the outer surface of the longitudinal extension of the rail core; and c) a polyurethane elastomer layer substantially covering the nonwoven fabric.

2. The impact protection barrier of claim 1 wherein the rail core is wood.

3. The impact protection barrier of claim 1 or 2 wherein the polyurethane elastomer of the polyurethane elastomer layer has a Shore D hardness of at most 65D.

4. The impact protection barrier of any one preceding claim wherein the polyurethane elastomer layer has a density of at least 0.8 g / cc.

5. The impact protection barrier of any one preceding claim wherein the nonwoven fabric of the nonwoven fabric layer comprises entangled and / or bonded fibers, wherein the fibers are selected from the group consisting of natural organic fibers, synthetic organic fibers and inorganic fibers.

6. The impact protection barrier of any one preceding claim wherein the non-woven fabric layer has an areal weight of 125 to 1700 g / m2.

7. A method of making an impact protection barrier of any one preceding claim, said method comprisingA) producing a reinforced rail by i) applying a nonwoven fabric directly or indirectly onto an outer surface of a longitudinal extension of a rail core to form a nonwoven fabric layer that substantially covers the outer surface of said longitudinal extension of the rail core; ii) applying a polyurethane-forming reaction mixture onto the nonwoven fabric such layer that the polyurethane-forming reaction mixture substantially covers the nonwoven fabric layer; andAtty Ref.: 157928.221088-WO (86147) iii) curing the polyurethane-forming reaction mixture to produce a polyurethane elastomer layer substantially covering the nonwoven fabric layer and produce the reinforced rail; andB) mounting the reinforced rail onto a pair of posts to produce the protection barrier.

8. A method of making in impact protection barrier of any one of claims 1-6, comprising1) applying a nonwoven fabric directly or indirectly onto an outer surface of a longitudinal extension of the rail core, the rail core being mounted onto a pair of posts such that the rail core is supported by the pair of posts, to form a nonwoven fabric layer that substantially covers the outer surface of the longitudinal extension of the rail core;2) applying a polyurethane-forming reaction mixture onto the nonwoven fabric layer such that the polyurethane-forming reaction mixture substantially covers the non-woven fabric layer; and3) curing the polyurethane-forming reaction mixture to produce polyurethane elastomer layer that substantially covers the nonwoven fabric layer and produce the reinforced rail mounted on and supported by the posts.

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