Device for the detection of BTEX using polymers with fluorobenzyl groups

Abstract

In a device (1A) for the detection of a BTEX component (3A) in a phase (5A), the device (1A) comprises a sensor (7A) for generating a signal (S) representative of the detection, the sensor comprising a layer (9A) of a material (11A) intended to be in physical contact with the phase, the material having the following formula (I): [Formula 1] TIFF2026508377000015.tif35166, wherein R-Bz is a unit that is repeated n times, n is an integer greater than 10, R is an organic group, and Bz has the following formula (Bz): [Case 2] TIFF2026508377000016.tif46166, wherein at least three independently selected ones of Z1, Z2, Z3, Z4 and Z5 are fluorine atoms, and at most two others are selected from hydrogen, halogen atoms and C1-C2 alkyl groups.

Description

[Technical Field]

[0001] The present invention relates to an apparatus for the detection of BTEX components in a liquid or gas phase, comprising a sensor adapted to generate a signal indicative of the detection.

[0002] The present invention also relates to methods for detecting BTEX components using such devices. [Background technology]

[0003] In the petroleum and petrochemical industries, BTEX refers to benzene, toluene, ethylbenzene, and xylene isomers, which are aromatic hydrocarbons considered individually or as mixtures. BTEX are usually present in the aqueous phase. Detecting these chemical components is important for managing potentially contaminated soil and groundwater within and from industrial sites. BTEX can also be present in the gas phase, such as polluted air.

[0004] Today, existing solutions are installed directly in the monitoring well, which requires the well to be drilled. Sometimes optical measurements of BTEX (e.g., using ultraviolet light around 260 nm) are performed. However, these direct solutions can be costly and suffer from calibration issues and drift due to exposure to contaminants. These solutions also have the potential to expose workers to contaminants.

[0005] More traditional indirect solutions require sampling by pumping groundwater to the surface. BTEX concentrations are then determined on-site using a portable analyzer or subsequently in a laboratory away from the industrial site. However, these solutions can result in significant delays between sampling and measurement, and can result in loss of contaminants during sample transportation.

[0006] To our knowledge, there is no permanent solution for this type of detection. Naturally, various techniques are known to detect all kinds of components, but none of them can address the problem of detecting chemical components such as BTEX in a liquid phase, such as water-saturated soil, or in a gas phase, such as the atmosphere. Summary of the Invention [Problem to be solved by the invention]

[0007] The object of the present invention is to solve or ameliorate the above-mentioned problems in order to enable the detection of BTEX components with particularly good sensitivity and selectivity, especially in difficult-to-access subsurface liquid phases or in the atmosphere. [Means for solving the problem]

[0008] To this end, the present invention provides a device for the detection of BTEX components in a liquid or gas phase, comprising a sensor adapted to generate a signal representative of the detection, the sensor comprising at least one layer of a material sensitive to the BTEX components and intended to be in physical contact with the phase, the material having the following formula: [ka] a polymer comprising a sequence of During the ceremony: R-Bz is a unit that is repeated n times, n is an integer greater than 10; R is an organic group, and Bz has the following formula: [ka] and an at least partially substituted benzyl group of the formula: We propose a device in which at least three independently selected ones of Z1, Z2, Z3, Z4, and Z5 are fluorine atoms, and at most two others of Z1, Z2, Z3, Z4, and Z5 are selected from hydrogen, halogen atoms, and C1-C2 alkyl groups.

[0009] In other embodiments, the device comprises one or more of the following features, taken separately or in any technically feasible combination: Z1, Z2, Z3, Z4 and Z5 are fluorine atoms; - R-Bz units have the following formula: [ka] wherein R1 is selected from among —CH2—, —C2H4—, and —C(O)O— groups, and each of R2, R3, and R4 is independently selected from among hydrogen and a C1-C6 alkyl group; - R1 is -C(O)O-; - R2 is -CH3 and R3 and R4 are hydrogen; - R2, R3 and R4 are hydrogen; - the layer extends on the surface of the sensor and has a thickness perpendicular to the surface, said thickness being between 600 and 1000 nm; - the sensor is a bulk acoustic wave sensor or a surface plasmon resonance sensor; - The sensor is a surface acoustic wave sensor; - The sensor is: - a piezoelectric substrate comprising lithium tantalate, the piezoelectric substrate having a longitudinally extending surface; - a comb transducer positioned on the surface for receiving an electrical signal and transmitting an electrical response signal, the comb transducer being adapted to convert the signal in a longitudinal direction into a surface acoustic wave; - at least one first mirror positioned on the surface and adapted to receive a first portion of the surface acoustic wave and to generate a first echo by mechanical reflection and / or re-radiation of said first portion of the surface acoustic wave towards the comb transducer; and - at least one first layer including a polymer, the first layer being positioned on the surface between the transducer and the first mirror and adapted to interact with the BTEX component to modify the speed of travel of the first echo along the first layer; It contains The transducer is adapted to convert the first echo into at least a portion of a response signal; - The sensor also: a second mirror positioned on the surface and adapted to receive a second portion of the surface acoustic wave and to generate a second echo by mechanical reflection or re-radiation of said second portion of the surface acoustic wave towards the transducer; - a second layer of metal and / or polymer positioned on the surface between the transducer and the second mirror; - a third mirror positioned on the surface and adapted to receive a third portion of the surface acoustic wave and to generate a third echo by mechanical reflection and / or re-emission of said third portion of the surface acoustic wave towards the transducer; and a third layer of metal and / or polymer positioned on the surface between the second mirror and the third mirror; It contains the transducer is adapted to receive the second echo and the third echo and convert the second echo and the third echo into at least a portion of a response signal; - the transducer and the first mirror comprise aluminum; - the transducer and / or the first mirror is a comb transducer having split fingers extending in a transverse direction perpendicular to the longitudinal direction; and The transducer and / or the first mirror is a comb transducer with sinusoidal apodization.

[0010] The present invention provides a method for detecting BTEX components in a liquid or gas phase, comprising: - obtaining a device as described above; - allowing physical contact between said layers and phases; - generating a signal indicative of the detection; - receiving and interpreting the signal; We also propose a method including:

[0011] The invention and its advantages will be better understood from reading the following description, given purely by way of example, and with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a schematic diagram of an apparatus according to the present invention; [Figure 2] FIG. 2 is a schematic diagram showing how, in the inventors' opinion, the polymers present in the device shown in FIG. 1 interact with the BTEX components. [Figure 3] FIG. 2 is a schematic perspective view of a practical installation including the device shown in FIG. 1. [Figure 4] FIG. 4 is a schematic front view of the sensor of the installation shown in FIG. 3. [Figure 5] FIG. 5 is a schematic front view of the comb transducer or mirror pattern of the sensor shown in FIGS. 3 and 4. [Figure 6] FIG. 6 is a schematic front view of a pattern forming a variation of the pattern shown in FIG. 5. [Figure 7] FIG. 6 is a schematic front view of a pattern forming a variation of the pattern shown in FIG. 5. [Figure 8] FIG. 5 shows the measured delay expressed as the phase difference between the second echo and the first echo (used as a reference) and between the third echo and the first echo, obtained using the sensor shown in FIGS. 3 and 4. DETAILED DESCRIPTION OF THE INVENTION

[0013] [Devices and Polymers] Now, with reference to FIG. 1, an apparatus 1A according to the present invention will be described.

[0014] The apparatus 1A is adapted to detect BTEX components 3A as defined above in a liquid or gas phase 5A.

[0015] The device 1A includes a sensor 7A adapted to generate a signal S representative of detection, the sensor 7A including at least one layer 9A of a material 11A sensitive to the BTEX component 3A and intended to be in physical contact with the phase 5A.

[0016] The sensor 7A is advantageously connected, by wire or wirelessly, to a remote system 13A adapted to receive the signal S. The sensor 7A may be of different types.

[0017] For example, sensor 7A is a surface acoustic wave (SAW) sensor.

[0018] In another embodiment, the sensor 7A is a bulk acoustic wave (BAW) sensor.

[0019] In one variant, sensor 7A is a surface plasmon resonance (SPR) sensor.

[0020] For example, phase 5A may be a liquid, such as groundwater, or a gas, such as air.

[0021] Material 11A has the following formula (I): [ka] a polymer comprising a sequence of During the ceremony: R-Bz is a unit that is repeated n times, n is an integer greater than 10; R is an organic group, and Bz is an at least partially substituted benzyl group.

[0022] Each of the Bz groups has the following formula (Bz): [ka] and wherein at least three independently selected ones of Z1, Z2, Z3, Z4 and Z5 are fluorine atoms, and at most two others of Z1, Z2, Z3, Z4 and Z5 are independently selected from hydrogen, halogen atoms and C1-C2 alkyl groups.

[0023] For example, a polymer may be formed by the sequence, with hydrogen or organic groups, such as alkyl groups, at both ends of the sequence.

[0024] For example, material 11A includes at least 90% by weight, preferably at least 99% by weight, of polymer, based on the total weight of material 11A.

[0025] The polymer is adapted to selectively interact with the BTEX component 3A and to modify the propagation velocity of SAW and BAW in the corresponding sensors or the optical index in the SPR sensor.

[0026] Without being bound by technical or scientific explanation, the inventors believe that pairs of Bz groups, where the two groups are sufficiently close to each other, can interact with the aromatic groups of BTEX component 3A through π-π stacking to retain the BTEX component, as shown in Figure 2. This provides selectivity to sensor 7A.

[0027] For example, the two Bz groups involved in π-π stacking preferably extend parallel to each other in the planes P1, P2 and are separated by a distance D1 of 0.30 to 0.80 nm, preferably 0.50 to 0.60 nm.

[0028] When phase 5A is an aqueous phase, the inventors also believe that the presence of at least three fluorine atoms in each of the Bz groups provides the polymer with hydrophobic properties that help attract BTEX component 3A (arrow F1) by pushing away water molecules 15A (arrow F2), thereby providing sensitivity to sensor 7A.

[0029] For example, the sensitive layer 9A has a contact angle of at least 110° (characterizing its hydrophobicity).

[0030] It is also believed that the -CH2- group linking each Bz group to an R group in the polymer advantageously provides solubility to the polymer, thereby allowing the deposition of thin layers of the polymer, for example by spin coating.

[0031] The layer 9A extends, for example, on the surface 17A of the sensor 7A and has a thickness E perpendicular to the surface 17A, said thickness E being advantageously between 600 and 1000 nm.

[0032] For example, n is 10 to 132.

[0033] In certain embodiments, all of the Bz groups in the n units have the same Z1, Z2, Z3, Z4 and Z5. As a variation, some of the Bz groups may be different from one another.

[0034] "Halogen" means a fluorine, chlorine, bromine or iodine atom.

[0035] Preferably, at least four of Z1, Z2, Z3, Z4 and Z5 are fluorine atoms.

[0036] More preferably, Z1, Z2, Z3, Z4 and Z5 are fluorine atoms. In other words, the Bz group is 2,3,4,5,6-pentafluorobenzyl.

[0037] For example, independently of formula (Bz), the R-Bz unit may be represented by the following formula (II): [ka] wherein R1 is selected from among —CH2—, —C2H4— and —C(O)O— groups, preferably —C(O)O—, and each of R2, R3, R4 is independently selected from among hydrogen and a C1-C6, preferably C1-C2 alkyl group.

[0038] Preferably, R1 is -C(O)O-.

[0039] In certain embodiments, R2 is -CH3 and R3 and R4 are hydrogen. The polymer then preferably has the following formula (III): [ka] The polymer is poly(2,3,4,5,6-pentafluorobenzyl methacrylate), or pPFBMA.

[0040] In another particular embodiment, R2, R3 and R4 are hydrogen. Preferably, the polymer then has the following formula (IV): [ka] The polymer is poly(2,3,4,5,6-pentafluorobenzyl acrylate), or pPFBA.

[0041] [Example of equipment with SAW sensors] The facility 10 will now be described with reference to FIG.

[0042] The installation 10 includes a device 12 according to the present invention (equivalent to device 1A in FIG. 1) exposed to the environment to be monitored, for example buried in soil 14 .

[0043] The installation 10 advantageously includes a system 18 (equivalent to system 13A in FIG. 1) positioned, for example, above the soil 14 and adapted to emit an electrical signal 20 to the device 12 and receive an electrical response signal 22 from the device via a line 24.

[0044] As a variation (not shown), the facility 10 may include multiple devices similar to those shown and / or multiple systems similar to the illustrated system 18.

[0045] Soil 14 is, for example, saturated with water and contains a BTEX component, such as toluene, to be detected by system 10. The BTEX component is, for example, carried or pushed by the water present in soil 14, where the BTEX component and water constitute a miscible or immiscible aqueous-liquid phase 23. The term "phase" here does not imply that the BTEX component is miscible with water.

[0046] In the illustrated embodiment, the system 10 is advantageously capable of detecting other chemical components, such as BTEX components distinct from toluene, or other analytes, such as H2S.

[0047] According to other variations, the system 10 may be capable of detecting more than two distinct chemical components.

[0048] By "detecting a chemical component" it is meant that the equipment 10 is adapted to provide information indicative of the presence of said chemical component in the vicinity of the device 12, preferably quantitatively or semi-quantitatively.

[0049] The device 12 is for example intended to remain within the soil 14 and is adapted to transmit information via a response signal 22 when interrogated by the system 18 .

[0050] The device 12 includes, for example, an enclosure 26 that is permeable to the liquid phase 23 and a sensor 28 positioned within the enclosure.

[0051] In one variant (not shown), the sensor 28 is wireless and is configured, for example, as a cooperative target for ground penetrating radar (per se known as GPR), in which case the sensor includes an antenna (not shown).

[0052] The enclosure 26 includes a grid 34 adapted to allow the liquid phase 23 containing, for example, BTEX components, to flow into the enclosure.

[0053] The grid 34 is advantageously located in the upper portion of the enclosure 26 .

[0054] The sensor 28 (FIGS. 3 and 4) is, for example, a SAW sensor.

[0055] In one variant (not shown), the sensor 28 is a BAW or SPR sensor.

[0056] In one embodiment, the sensor 28 includes a piezoelectric substrate 36 having a surface 38 extending in a longitudinal direction L, and an interdigital transducer IDT positioned on the surface 38 and adapted to convert the signal 20 into a surface acoustic wave 40 in the longitudinal direction L by the piezoelectric effect.

[0057] The sensor 28 includes a first mirror M1 positioned on the surface 38 and adapted to receive a first portion of the surface acoustic wave 40 and generate a first echo E1 toward the transducer IDT by mechanical reflection and / or re-emission of the first portion of the surface acoustic wave. The sensor 28 includes at least a first layer 41 of the polymer positioned on the surface 38 between the transducer IDT and the first mirror M1, the polymer adapted to react with the BTEX component to modify the speed of travel of the first echo E1 along the first layer 41.

[0058] The sensor 28 advantageously includes a second mirror M2 and a third mirror E3 positioned on the surface 38 and adapted to receive the second and third portions of the surface acoustic wave 40 and to generate second and third echoes E2 and E3 towards the transducer IDT by mechanical reflection or re-radiation of said second and third portions of the surface acoustic wave.

[0059] The sensor 28 advantageously includes at least a second layer 42 of said polymer positioned on the surface 38 between the transducer IDT and the second mirror M2, and a third layer 43 of polymer positioned on the surface 38 between the second mirror M2 and the third mirror M3.

[0060] In certain embodiments, the sensor 28 further comprises a fourth mirror M4 (shown only in FIG. 4 ) positioned on the surface 38 and adapted to receive a fourth portion of the surface acoustic wave and generate a fourth echo E4 towards the transducer IDT by mechanical reflection and / or re-emission of said fourth portion of the surface acoustic wave. The sensor 28 advantageously comprises a fourth layer 45 comprising a metal and / or a second polymer, the fourth layer being positioned on the surface 38 between the first mirror M1 and the fourth mirror M4.

[0061] The sensor 28 is advantageously configured to form a reflective delay line to create four echoes E1-E4 in the example.

[0062] In an embodiment, the first layer 41, the second layer 42 and the third layer 43 are of the same nature and provide redundant information.

[0063] The second polymer may be polyisobutene (PIB).

[0064] In a particular embodiment (not shown), the first echo E1 may serve as a reference for the other echoes.

[0065] In other embodiments (not shown), depending on the nature and number of layers 41, 42, 43, 45, the echoes can provide information about temperature-induced drift, and / or the detection of other chemical components (if the second polymer is different from the polymer), and / or redundancy in the detection of BTEX components or other elements.

[0066] Other relative positions for these elements are possible, depending on the number of mirrors and the nature of the layers on surface 38 between the mirrors and the transducer IDTs.

[0067] Sensor 28 is advantageously constructed such that surface acoustic waves 40 along first layer 41 and advantageously layers 42, 43 and 45 comprise Love waves, thereby maximizing energy containment within sensor 28 and maximizing its gravimetric sensitivity.

[0068] The substrate 36 is advantageously made of stoichiometric lithium tantalate (LiTaO), for example YXI / 36°, although any crystal orientation that generates quasi-shear waves (e.g., YXI / 42°) will meet the requirements for a sensor operating in liquid.

[0069] The substrate 36 is adapted to propagate quasi-shear waves that can be confined to the surface 38 either by metallizing the free surface to slow down the waves and thus trapping the energy at the surface through conductive boundary conditions and / or by coating the surface with a polymer that has a slower acoustic velocity than the shear waves in the bulk of the piezoelectric substrate.

[0070] The substrate 36 is, for example, a rectangular plate having a length of, for example, 10 mm in the longitudinal direction L and a width of, for example, 3 mm in the transverse direction T perpendicular to the longitudinal direction L. The substrate 36 has a thickness of, for example, 300 to 500 μm, which is thick enough to avoid interaction of the surface acoustic waves with the opposite side of the wafer.

[0071] In certain embodiments, the transducer IDT, the first mirror M1, the second mirror M2, the third mirror M3, and the fourth mirror M4 are structurally similar to each other.

[0072] For example, the second mirror M2 and the third mirror M3 (if present) are on one side of the transducer IDT, while the first mirror M1 and the fourth mirror M4 (if present) are on the other side in the longitudinal direction L. For example, the third mirror M3 is further away from the transducer IDT than the second mirror M2, and the fourth mirror M4 is further away from the transducer than the first mirror M1.

[0073] Advantageously, the mirrors are positioned along the longitudinal direction L so that the echoes they create are received sequentially by the transducer IDTs and are easily separated from one another, for example with at least 0.5 μs between them.

[0074] The transducer IDT is adapted to convert the first echo E1, and in the embodiment the second echo E2, the third echo E3 and the fourth echo E4, into a response signal 22 by the piezoelectric effect.

[0075] In the example embodiment, since electrical re-radiation is used as the reflection method rather than mechanical reflection at the low (less than 500 MHz) frequencies considered here, the transducer IDT, first mirror M1, second mirror M2, third mirror M3 and fourth mirror M4 are structurally similar to each other (although not represented in a similar manner in Figure 3), and therefore only the transducer IDT will be described below.

[0076] As a variant (not shown), the mirrors M1 to M4 may be different from the transducer IDTs and / or may differ from each other, for example by adjusting the number of electrodes in each mirror, so that the returned power is the same for all echoes.

[0077] The transducer IDTs are advantageously formed from a single patterned layer of metal, for example aluminum, or gold if corrosion resistance is desired.

[0078] The transducer IDT includes two electrodes 44, 46 (FIGS. 4 and 5), each including two longitudinally extending and transversely spaced apart bases 48, 50. Each of the electrodes 44, 46 includes two sets of fingers 52, 54 that project transversely from one of the bases 48, 50 to the other and vice versa.

[0079] The fingers 52 from one set alternate with the fingers 54 of the other set along a midline D parallel to the longitudinal direction L, so that the transducer IDT is an interdigitated structure.

[0080] In the illustrated embodiment, each of the fingers 52 of one of the two sets faces a corresponding finger 54 of the other set in the transverse direction.

[0081] The fingers 52, 54 are separated in the transverse direction by a distance D2 (FIG. 4) of, for example, 10 μm. The shortest finger has a length D3 in the transverse direction T of, for example, 10 μm.

[0082] 4 and 5, each of the fingers 52, 54 is a split finger. Each finger is divided into two half fingers 52A, 52B. For example, the width of a half finger in the longitudinal direction L is equal to the distance between the half fingers.

[0083] In one embodiment, in each of the two finger sets 52, 54, one of the two fingers in the longitudinal direction L defines a first sinusoidal portion S1, and the other of the two fingers defines a second sinusoidal portion S2, so that the transducer IDT has a sinusoidal apodization. Each of the first sinusoidal portion S1 and the second sinusoidal portion S2 corresponds to, for example, one-half period. The fingers forming the first sinusoidal portion S1 or the second sinusoidal portion S2 define a longitudinal period D4 of, for example, 41 μm.

[0084] The fingers 52, 54 and bases 48, 50 have a thickness in the direction perpendicular to the substrate 36 of, for example, 0.5 μm.

[0085] 6, the fingers 52, 54 are not divided. The width of the fingers 52, 54 is for example equal to the distance between two consecutive fingers in the longitudinal direction L.

[0086] According to another variant shown in FIG. 7, each set of fingers 52, 54 comprises long and short fingers alternating in the longitudinal direction, so that the transducer IDT has a simple apodization.

[0087] The echo is advantageously stronger with split finger and sinusoidal apodization structures.

[0088] The primary mechanisms for transmitting waves from the mirror back toward the IDT are mechanical reflection and re-radiation. The former effect is induced by mechanical mass-loading reflections on the one hand, and by acoustic velocity variations induced by electrical boundary condition changes as the wave propagates from free space to the metalized areas when the electrodes are patterned on the other. It has been noted that these two effects have opposite signs in the case of lithium niobate substrates and are additive in the case of lithium tantalate. In re-radiation, the incident acoustic wave induces currents in the mirror electrodes, which induce stresses in the crystal lattice of the substrate 36 and thus new acoustic waves that propagate in both directions away from the mirror structure patterned as the IDT itself. This has been observed to generate the strongest echoes and produce the lowest insertion loss in the reflection coefficient.

[0089] The thickness of the polymer layer makes it possible to optimize the gravimetric sensitivity through the confinement of the elastic waves within the polymer, which induces wave motion in the Love mode approach.

[0090] The layers 41 , 42 , 43 , 45 are advantageously adapted to guide and confine the acoustic waves and their echoes within the substrate 36 .

[0091] The system 18 is advantageously adapted to use the response signal 22 for the purpose of detecting BTEX components.

[0092] As a variant, the system 18 is adapted to transmit the reply signal 22 to a remote computer (not shown) adapted to use the reply signal.

[0093] The center frequency of the signal 20 is, for example, 100 to 500 MHz.

[0094] The operation of the system 10, which derives from its construction, will now be described for purposes of illustrating the method of detecting BTEX components according to the present invention.

[0095] In an embodiment, the goal is to detect BTEX components in the water-miscible or water-immiscible liquid phase within water-saturated soil 14.

[0096] For example, a signal 20 is emitted by the system 18 and then received by the transducer IDT and converted into a surface acoustic wave 40 in the longitudinal direction L.

[0097] A first portion of the surface acoustic wave 40 is received by the first mirror M1, which generates a first echo E1 by mechanical reflection and / or re-radiation of the first portion of the surface acoustic wave towards the interdigital transducer IDT. The first layer 41 ensures that the first portion of the surface acoustic wave and the first echo E1 can travel along the substrate 36.

[0098] The second and third portions of the surface acoustic wave 40 are received by the second mirror M2 and the third mirror M3, which generate a second echo E2 and a third echo E3 towards the transducer IDT by mechanical reflection or re-radiation of the second and third portions of the surface acoustic wave 40.

[0099] In the example, enclosure 26 allows a liquid phase 23 surrounding device 12 to contact first layer of polymer 41. When BTEX components are present in liquid phase 23, they interact with the polymer and modify the speed of travel of the acoustic waves along first layer 41 and third layer 43, which affects first echo E1 and third echo E3 as shown in FIG.

[0100] The first echo E1, the second echo E2, and the third echo E3 are converted by the interdigital transducer IDT into at least a portion of a response signal 22. The response signal 22 represents the first echo E1, the second echo E2, and the third echo E3.

[0101] The response signal 22 is then used to detect BTEX components, and advantageously other chemical components.

[0102] By virtue of the above features, the device 12 allows for the detection of BTEX components with excellent sensitivity and selectivity.

[0103] Polymer Synthesis and Deposition Examples [ka]

[0104] 10 grams of 2,3,4,5,6-pentafluorobenzyl alcohol (50.5 mmol) are reacted in 7 mL (47 mmol) of methacrylic anhydride at 110° C. for 4 hours.

[0105] The crude oil obtained is washed thoroughly with a solution of 10% w / v aqueous potassium carbonate. The pure compound is obtained by distillation of this mixture (boiling point: 118° C. at 40 mbar).

[0106] [ka]

[0107] The corresponding polymer was obtained by heating 3 mL of (2,3,4,5,6-pentafluorobenzyl) methacrylate with 40 mg of benzoyl peroxide as a catalyst at 70 °C for 2 hours. The transparent block material was dissolved in 20 mL of dichloromethane, and the solution was added dropwise to 200 mL of ethanol. Poly(2,3,4,5,6-pentafluorobenzyl methacrylate) (pPFBMA) was obtained as a white powder by filtration.

[0108] pPFBMA 1 The number of repeating units was determined to be 50 by in-depth analysis of the 1 H NMR spectrum.

[0109] The lithium tantalate piezoelectric substrate 36 of the reflective delay line acoustic sensor, fabricated by patterning the Al interdigitated electrodes and mirrors, is thoroughly cleaned with dichloromethane, acetone, ethanol, and then propan-2-ol. The surface is activated by anisotropic oxygen plasma for 5 minutes. A monolayer of TiPrime (adhesion promoter) is applied to the substrate using a spin coater (900 rpm for 30 seconds). 2 The sensor is then deposited at a speed of 3000 rpm with an acceleration of 100 rpm. A 15% w / v solution of pPFBMA in 1,2-dichloroethane is then deposited under the same spin-coating conditions to obtain a polymer layer with a thickness of 600-1000 nm. The functionalized acoustic sensor is then baked at 110 °C for 2 h.

[0110] [Experimental detection of BTEX] A SAW sensor 28, as described above, functionalized with 850 nm thick pPFBMA layers 41, 42, and 43, was exposed to aqueous solutions with different concentrations of toluene, followed by rinsing with water after each toluene exposure. The phase variation was monitored as a function of exposure duration, using the sensor operating at a frequency of 100 MHz.

[0111] The results are shown in Figure 8, where the phase shift (in degrees) of the first echo E1 (top of Figure 8) and the phase shift of the third echo E3 (bottom) are plotted as a function of time (in hours).

[0112] If f is the center frequency of the sensor and τ is the time delay of the echoes, i.e., 800 ns for the first echo E1 and 2400 ns for the third echo E3, then φ=2πfτ and dτ is the time delay difference between the echoes, leading to the differential measurement dφ=2πfdτ.

[0113] The phase shift is proportional to the toluene concentration and the acoustic delay, with echo E3 returned by the mirror at three times the delay of echo E1.

[0114] Experiments demonstrate the sensor's ability to efficiently detect toluene in aqueous solutions. Measurements were performed in a wired configuration using a Rohde & Schwarz ZVC8 vector network analyzer. The time-domain response of the sensor was deduced from the frequency-domain measurements made by the network analyzer by calculating the inverse Fourier transform and selecting the phase at the location of the return power maximum.

[0115] The exposure sequence in terms of toluene concentration in water was as follows: 1) 0.19gL -1 2) 0.05gL -1 3) 0.12gL -1 4) 0.14gL -1 5) 0.19gL -1

[0116] Concentrations were deduced from the UV absorption of the solution around 260 nm.

[0117] Upon exposure of the SAW sensor 28 to the toluene-water solution, a rapid decrease in phase was observed. The phase shift was proportional to the toluene concentration. Subsequent rinsing with the water solution provided an initial baseline (i.e., no phase shift).

[0118] In this experiment, toluene at a concentration of 0.19 g / L in water was injected 0.5 to 1 hour after the water baseline, followed by water injections to return to this baseline level, demonstrating the reversibility of toluene absorption by the sensing layer. A concentration of 0.05 g / L was injected at 2.5 hours, followed by 0.12 g / L, followed by a 5 hour rinse in pure water to return to baseline. Three additional series of increasing concentrations, 0.14 g / L, 0.15 g / L, and 0.19 g / L, were injected over a period of 5.5 to 12 hours, with water used to clean the entire setup for 12 to 25 hours, along with water rinses to return to baseline between each exposure step, to demonstrate the stability of the polymer layer 41 to long-term exposure to water.

[0119] The experiments were performed in a laboratory setup with minimal temperature fluctuations (less than 1 K for the entire duration of the experiment), allowing for a reproducible analysis of measurements on two sensing layers 41 and 42 made of the same polymer layer.

[0120] Toluene concentrations in all waters were measured at the beginning and end of the exposure sequence using UV-Vis (ultraviolet-visible) absorbance at 261 and 268 nm.

[0121] In another practical implementation, layers 41, 42 and 43 could be different as explained above.

[0122] It was also confirmed that layers 41 and 42 were not sensitive to the presence of non-BTEX components such as ethanol. The sensor was exposed to an ethanol-water solution with 10% ethanol by weight, but no phase shift was measured. [Explanation of symbols]

[0123] 12 Detection device 20 Electrical Signals 22 Electrical response signal 28 sensors 36 Piezoelectric substrate 38 Surface 40 Surface Acoustic Waves 41 First Layer 42 Second Layer 43 Third Layer 52, 54 Split Finger 1A Detection device 3A BTEX component 5A Liquid or gas phase 7A sensor 17A surface E Thickness E1 First echo E2 Second echo E3 The Third Echo M1 First Mirror M2 Second mirror M3 Third Mirror S Signal indicating detection

Claims

1. 1. A device (1A; 12) for the detection of a BTEX component (3A) in a liquid or gaseous phase (5A), comprising a sensor (7A; 28) adapted to generate a signal (S) representative of the detection, wherein the sensor (7A; 28) comprises at least one layer (9A; 41) of a material (11A) sensitive to the BTEX component (3A) and intended to be in physical contact with the phase (5A), the material (11A) being of the following formula (I): 【Chemistry 1】 a polymer comprising a sequence of During the ceremony: R-Bz is a unit that is repeated n times, n is an integer greater than 10; R is an organic group, and Bz is an at least partially substituted benzyl group of the following formula (Bz): 【Chemistry 2】 During the ceremony: At least three independently selected ones of Z1, Z2, Z3, Z4 and Z5 are fluorine atoms; and At most two others of Z1, Z2, Z3, Z4 and Z5 are hydrogen, halogen atoms and C １ ~C ２ alkyl groups, Device.

2. 12. The device (1A; 12) according to claim 1, wherein Z1, Z2, Z3, Z4 and Z5 are fluorine atoms.

3. The R-Bz unit has the following formula (II): 【Transformation 3】 wherein R1 is —CH ２ -, -C ２ H ４ - and -C(O)O- groups, Each of R2, R3, and R4 is hydrogen and C １ ~C ６ independently selected from alkyl groups, 3. An apparatus (1A; 12) according to claim 1 or 2.

4. 4. The device (1A; 12) of claim 3, wherein R1 is —C(O)O—.

5. R2 is -CH ３ and R3 and R4 are hydrogen.

6. 5. The device (1A; 12) of claim 4, wherein R2, R3 and R4 are hydrogen.

7. 7. The device (1A; 12) according to claim 1, wherein the layer (11A; 41) extends on the surface (17A; 38) of the sensor (7A; 28) and has a thickness (E) perpendicular to the surface (17A; 38), said thickness (E) being between 600 nm and 1000 nm.

8. 8. The device (1A) according to any one of claims 1 to 7, wherein the sensor (7A) is a bulk acoustic wave sensor or a surface plasmon resonance sensor.

9. 8. The apparatus (12) of any one of claims 1 to 7, wherein the sensor (28) is a surface acoustic wave sensor.

10. The sensor (28): a piezoelectric substrate (36) comprising lithium tantalate, the piezoelectric substrate (36) having a surface (38) extending in a longitudinal direction (L); an interdigital transducer (IDT) positioned on the surface (38) for receiving an electrical signal (20) and transmitting an electrical response signal (22), the interdigital transducer (IDT) being adapted to convert the signal (20) into a surface acoustic wave (40) in a longitudinal direction (L); at least one first mirror (M1) positioned on the surface (38) and adapted to receive a first portion of the surface acoustic wave (40) and to generate a first echo (E1) towards the interdigital transducer (IDT) by mechanical reflection and / or re-radiation of said first portion of the surface acoustic wave (40); at least one first layer (41) comprising a polymer, positioned on the surface (38) between the transducer (IDT) and the first mirror (M1) and adapted to interact with the BTEX component to modify the speed of travel of the first echo (E1) along said first layer (41); It contains a transducer (IDT) adapted to convert the first echo (E1) into at least a portion of a response signal (22); 10. The device (12) according to claim 9.

11. The sensor (28) further comprises: a second mirror (M2) positioned on the surface (38) and adapted to receive a second portion of the surface acoustic wave (40) and to generate a second echo (E2) towards the transducer (IDT) by mechanical reflection or re-radiation of said second portion of the surface acoustic wave (40); a second layer (42) of metal and / or polymer positioned on the surface (38) between the transducer (IDT) and the second mirror (M2); a third mirror (M3) positioned on the surface (38) and adapted to receive a third portion of the surface acoustic wave (40) and to generate a third echo (E3) towards the transducer (IDT) by mechanical reflection and / or re-radiation of said third portion of the surface acoustic wave (40); a third layer (43) of metal and / or polymer positioned on the surface (38) between the second mirror (M2) and the third mirror (M3); It contains a transducer (IDT) adapted to receive the second echo (E2) and the third echo (E3) and convert the second echo (E2) and the third echo (E3) into at least a portion of a response signal (22); 11. The device (12) according to claim 10.

12. 12. The device (12) according to claim 10 or 11, wherein the transducer (IDT) and the first mirror (M1) comprise aluminum.

13. 13. The device (12) according to any one of claims 10 to 12, wherein the transducer (IDT) and / or the first mirror (M1) is a comb transducer having split fingers (52, 54) extending in a transverse direction (T) perpendicular to the longitudinal direction (L).

14. 14. The device (12) according to any one of claims 10 to 13, wherein the transducer (IDT) and / or the first mirror (M1) is a comb transducer with sinusoidal apodization (S1, S2).

15. 1. A method for detecting a BTEX component (3A) in a liquid or gas phase (5A): - obtaining a device (1A; 12) according to any one of claims 1 to 14, - allowing physical contact between said layer (11A; 41) and phase (5A); generating a signal (S; 22) representative of the detection; - receiving and interpreting a signal (S;22); A method comprising:

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