MULTILAYER STRUCTURE FOR TRANSPORTING OR STORING HYDROGEN

Abstract

A multilayer structure for transporting hydrogen, including, from the inside, a sealing layer and at least one composite reinforcement layer, an innermost composite reinforcement layer being wound around the sealing layer, the sealing layer being a composition predominantly of: a polyamide thermoplastic polymer PA11, up to less than 15% by weight of impact modifier, up to 1.5% by weight of plasticizer relative to the total weight of the composition, the composition being devoid of nucleating agent and of polyether block amide (PEBA), and at least one of the composite reinforcement layers being a fibrous material in the form of continuous fibers, which is impregnated with a composition predominantly of at least one polymer P2j, (j=1 to m, m being the number of reinforcement layers), the structure being devoid of an outermost layer and adjacent to the outermost layer of a composite reinforcement layer made of a polyamide polymer.

Claims

1. A multilayer structure intended for transporting, distributing, or storing hydrogen, comprising, from the inside to the outside, at least one sealing layer and at least one composite reinforcement layer, an innermost composite reinforcement layer being wound around said sealing layer, said sealing layer consisting of a composition comprising: a thermoplastic polyamide polymer PA11, up to less than 15% by weight of impact modifier relative to the total weight of the composition, up to 1.5% by weight of plasticizer relative to the total weight of the composition, said composition being devoid of nucleating agent and polyether block amide (PEBA), and at least one of said composite reinforcement layers consisting of a fibrous material in the form of continuous fibers, which is impregnated with a composition predominantly comprising at least one polymer P2j, j=1 to m, m being the number of reinforcement layers, in particular an epoxide resin or epoxide-based resin, said structure being devoid of an outermost layer and adjacent to the outermost composite reinforcement layer made of a polyamide polymer.

2. The multilayer structure according to claim 1, wherein each reinforcement layer comprises the same type of polymer, in particular an epoxide resin or epoxide-based resin.

3. The multilayer structure according to claim 1, wherein it has a single reinforcement layer.

4. The multilayer structure according to claim 1, wherein said polymer P2j is an epoxide resin or epoxide-based resin.

5. The multilayer structure according to claim 3, wherein said multilayer structure is composed of a single reinforcement layer and said polymer P2j is an epoxide resin or epoxide-based resin.

6. The multilayer structure according to claim 1, wherein the fibrous material of the composite reinforcement layer is selected from glass fibers, carbon fibers, basalt fibers or basalt-based fibers, or a mixture thereof.

7. The multilayer structure according to claim 1, wherein said structure further comprises at least one outer layer consisting of a fibrous material made of continuous glass fibers, which is impregnated with a transparent amorphous polymer, said layer being the outermost layer of said multilayer structure.

8. A method for producing a multilayer structure as defined in wherein it comprises a step of preparing the sealing layer by extrusion blow molding, rotational molding, injection molding and/or extrusion.

9. The method for producing a multilayer structure according to claim 8, wherein it comprises a step of filament winding of the reinforcement layer around the sealing layer.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0184] FIG. 1 presents the Charpy impact test notched at −40° C. according to ISO 179−1: 2010 with four liners: from left to right PA11, PA12, PA6 and PA66.

[0185] FIG. 2 presents the permeability to hydrogen at 23° C. of the PA12 and HDPE liners.

[0186] It is expressed in cc.Math.mm/m.sup.2.Math.24 h.Math.atm. It can be expressed in cc. 25 μ/m.sup.2.Math.24 h.Math.Pa.

[0187] The permeability must then be multiplied by 101325.

[0188] FIG. 3 presents the Charpy impact test notched at −40° C. according to ISO 179−1:2010 for PA11 and PA12 liners: for each group of histograms, PA11 is on the left and PA12 is on the right. The first group corresponds to 0% of plasticizer, the second group to 7% of plasticizer and the last group to 12% of plasticizer.

EXAMPLES

[0189] In all examples, the reservoirs are obtained by rotational molding of the sealing layer (liner) at a temperature adapted to the nature of the thermoplastic resin used.

[0190] In the case of the composite reinforcement being made of epoxide resin or epoxide-based resin, use is then made of a process of wet filament winding, which consists in winding fibers around the liner, which fibers have been previously pre-impregnated in a bath of liquid epoxide or a bath of epoxide-based liquid. The reservoir is then polymerized in an oven for 2 hours.

[0191] In all other cases, a fibrous material previously impregnated with the thermoplastic resin (tape) is used. This tape is deposited by filament winding using a robot with a 1500 W laser heater at a speed of 12 m/min and there is no polymerization step.

Example 1

[0192] Charpy Impact Test Notched at −40° C. According to ISO 179−1: 2010

[0193] Two long-chain liners made of PA11 and PA12 and two short-chain liners were prepared by rotational molding as above.

[0194] These four liners were tested via a Charpy impact test notched at −40° C. and the results are presented in FIG. 1.

[0195] The resistance to cold of the PA11 liner is considerably greater than that of the long-chain PA12 liner and short-chain PA6 and PA66 liners.

Example 2

[0196] Permeability of PA 11 and PA12 liners (Arkema) and HDPE liners (Marlex® HMN TR-942 (Chevron Phillips))

[0197] Two long-chain liners: one in PA11 (Arkema) and the second in PA12 (Arkema) and one HDPE liner were prepared by rotational molding and the permeability to hydrogen at 23° C. was tested.

[0198] This consists in flushing the upper face of the film with the test gas (Hydrogen) and in measuring by gas chromatography the flow that diffuses through the film in the lower part, flushed by the vector gas: Nitrogen

[0199] The experimental conditions are presented in Table 1:

TABLE-US-00001 TABLE 1 Device LYSSY GPM500/GC coupling Detection Chromatographic (TCD) Column Poraplot Q (L = 27.5 m, Dint = 0.530 mm, Ep. film = 20 μ) Vector gas NITROGEN Diffusing gas HYDROGEN U (H2) Test surface area 50 cm.sup.2 Calibration Absolute by direct injection through a septum Pressure at column 18 psi head Oven temperature Isothermal 30° C. Detector temperature 200° C. detector: TCD [−] Injector temperature Temperature of the lyssy injection loop Temperature/relative 23° C./0% RH humidity

[0200] The results are presented in FIG. 2 and show that the PA11 liner has much lower permeability than that of a long-chain liner made of PA12 and a HDPE liner.

Example 3

[0201] influence of the proportion of plasticizer (N-butylbenzenesulfonamide: BBSA) on the Charpy impact test notched at −40° C. according to ISO 179−1: 2010

[0202] Two PA11 and PA12 liners without plasticizer or comprising 7 or 12% plasticizer (BBSA) with respect to the total weight of the composition were prepared by rotational molding.

[0203] These four liners were tested via a Charpy impact test notched at −40° C. according to ISO 179−1: 2010 and the results are presented in FIG. 3.

[0204] Indeed, the plasticizer has a more pronounced deleterious effect when cold for the PA12 than the PA11; it weakens the structure of the PA12 and increases the permeability, particularly from 50% with 7% BBSA.

Example 4

[0205] Influence of the proportion of impact modifier (“LT cocktail” with the following composition: lotader® 4700 (50%)+lotader® AX8900 (25%)+Lucalen® 3110 (25%)) on the permeability to hydrogen of the PA11 liner.

[0206] The permeability to hydrogen of the PA11 liner, without a plasticizer and whether or not in the presence of an impact modifier was tested and is reported in Table 2.

TABLE-US-00002 TABLE 2 Liner Permeability (cc.Math.25 μ/m.sup.2.Math.24 h.Math.atm) PA11 only 5000 PA11 + 18% impact modifier 10,000 PA11 + 30% impact modifier 15,000

[0207] The permeability can also be expressed in (cc. 25 μ/m.sup.2.Math.24 h.Math.Pa).

[0208] The permeability must then be multiplied by 101325.

[0209] The results show that the proportion of impact modifier influences the permeability to hydrogen.

[0210] The greater the proportion of impact modifier, the greater the permeability.

Example 5

[0211] Type IV hydrogen storage tank, composed of a T700SC31E (produced by Toray) carbon fiber epoxide composite reinforcement (Tg 120° C.) and a PA11 sealing layer.

[0212] The operating temperature is sufficient for rapid filling of the tank, particularly in 3 to 5 minutes.

Example 6 Counterexample

[0213] Type IV hydrogen storage tank, composed of a T700SC31E (produced by Toray) carbon fiber epoxide composite reinforcement (Tg 120° C.) and an HDPE sealing layer.

[0214] The operating temperature is too low for rapid filling of the tank, particularly in 3 to 5 minutes.

Example 7

[0215] Type IV hydrogen storage tank, composed of a T700SC31E (produced by Toray) carbon fiber BACT/10T composite reinforcement and a PA11 sealing layer.

[0216] The selected BACT/10T composition has a melting temperature, Tm, of 283° C., a crystallization temperature, Tc, of 250° C. and a glass transition temperature of 164° C.

[0217] The Tg, the Tc and the Tm are determined by differential scanning calorimetry (DSC) according to standards 11357−2:2013 and 11357−3:2013, respectively.

[0218] A PA BACT/10T-based composite has a high Tg matrix, but without long cross-linking, of the 8 h type at 140° C.

[0219] As a result, after depositing the fiber, the tank is complete, which saves 8-hours of process time.