Dye-exchanged zeolite markers

Abstract

Dye-exchanged zeolite markers, wherein the zeolite is characterized by a pore size of 5 to 10 A and the dye is an organic cationic molecule, characterized in that the amount of dye is 0.05 to 1 wt.-% relative to the weight of the zeolite; optically active compositions comprising dye-exchanged zeolite markers dispersed in a polymer matrix; and their use as detectable markers.

Description

Background Technology

[0001] The present invention relates to zeolite markers for dye exchange and optically active compositions comprising said markers dispersed in a polymer matrix.

[0002] Numerous patent publications (e.g., EP1409997, EP1356478, WO2011045572, WO2021113377, or US20100003762) relate to the preparation of marking materials for a wide range of possible applications (e.g., for anti-counterfeiting purposes, for inventory control or warranty purposes, for detecting the presence of a specific substance in a specific medium, or as a package solution). Known means of detecting a specific substance are exemplified by the use of colorimetric indicators that rely on the optical properties of reactive dyes or inks under specific conditions. In particular, these dyes can exist in at least two different chemical states, each form of the dye absorbing light within a specific wavelength range. When such a reactive dye in its first form is exposed to a given substance, it reacts with the substance through a reversible chemical reaction, thereby transforming into a second form of the dye. Since the second form of the dye absorbs light at a different wavelength, the chemical reaction provides a visible and therefore detectable color change.

[0003] Integrating these molecules into a desired substrate (which also includes the possibility of using zeolite) is typically achieved by impregnation methods as disclosed in WO2011045572 or by post-processing methods as reported in US11027241. Furthermore, CN110903826 discloses the use of fluorescent molecules, such as rhodamine, integrated onto the surface of a metal-organic framework (MOF) structure using diffusion impregnation technology. Meanwhile, WO2021113377 describes antimicrobial zeolite nanoparticles that, in addition to metallic substances, may also contain optical tracers (e.g., fluorophores) non-covalently or covalently bound to the surface of the zeolite but not within the pores of the nanoparticles.

[0004] The main drawback of this method relates to the limited stability of the final system, which tends to readily release dye molecules and decompose when exposed to heat treatment, such as in the case of a thermoplastic matrix under extrusion processing, or in the presence of water or other solvents.

[0005] Another possible method is based on the use of pigments, as reported in WO2005052069, in which the pigment composition is achieved by a substitution reaction with one or more cationic dye groups in the presence of a suspension of zeolite pigments. However, one of the negative consequences of using both organic and inorganic pigments as disclosed in WO2005052069 is related to the large amount of dye relative to the amount of zeolite, and the resulting high dye / zeolite ratio required to achieve the desired coloring effect.

[0006] Therefore, there remains a need to develop new chemical indicators, and in particular markers, to provide simple, reliable, and cost-effective detection methods that exhibit improved stability compared to those known in the art, especially when subjected to heat or contact with solvents. Furthermore, there is a need to develop new optically active compositions incorporating such markers, which can be prepared and processed using known polymer processing techniques while maintaining the efficacy and stability of the new indicators. Summary of the Invention

[0007] This invention overcomes the aforementioned shortcomings of the prior art by preparing dye-exchanged zeolite-labeled products through a cation exchange reaction between the positive ions of zeolite and the positive ions of dye organic molecules.

[0008] In the context of this disclosure, the term "dyed-exchange zeolite marker" should be interpreted as being well known in the art, and particularly as meaning a marker or indicator based on zeolite and obtainable by a cation exchange reaction between a cationic dye and zeolite. The abbreviation "marker" may be used interchangeably with "dyed-exchange zeolite marker".

[0009] More specifically, in order to provide a marker material capable of overcoming the prior art problems associated with the low stability disclosed above, the inventors of the present invention have unexpectedly discovered that when a cation exchange reaction occurs between the dye and the zeolite, the dye binds more effectively to the zeolite, particularly into the zeolite pores, and is therefore not released or decomposed upon contact with solvents or under high temperature conditions, i.e., it is more stable than those known in the art.

[0010] Therefore, the present invention relates to zeolite markers comprising dye exchange of zeolite and dye organic molecules, wherein the markers are obtained by a cation exchange reaction between at least one cation of zeolite and at least one cation of dye organic molecules.

[0011] Furthermore, it has been demonstrated that the detectable properties of the obtained markers can still be measured without altering the surface properties of the zeolite or its suitability for different applications, by using a reduced amount of dye molecules relative to the zeolite. Therefore, the present invention also relates to zeolite markers comprising dye exchange of zeolite and dye organic molecules, wherein advantageously, the weight ratio between the dye and zeolite is 0.05 wt% to 1 wt%, preferably 0.1 wt% to 0.5 wt%, relative to the weight of the zeolite. In other words, contrary to what is disclosed in the prior art, the markers of the present invention do not require a high dye / zeolite ratio to achieve the coloring purpose.

[0012] As will become apparent from the experimental portion of this disclosure, the measurement of zeolite pore size can play a crucial role in the preparation of the dye-exchange zeolite markers of the present invention (at least in terms of process yield). Pore sizes have been found to be... to Zeolite dye exchange is particularly advantageous.

[0013] The present invention also relates to optically active compositions comprising zeolite markers for dye exchange disclosed herein and a polymer matrix, preferably wherein the markers are dispersed within the polymer matrix.

[0014] Furthermore, the present invention relates to the use of the dye-exchange zeolites or compositions disclosed herein as detectable markers, and to detectable articles comprising, embedded in, or coated with dye-exchange zeolites or compositions according to the present invention (at least in part). Attached Figure Description

[0015] Figure 1 shows the results of thermogravimetric analysis combined with mass spectrometry (TG-MS) to assess the release of organic vapors from samples C2 and S2 during processing simulation. During heating to 250 °C, for sample C2, it was clearly determined that some organic matter was released due to the initiation of decomposition, while for sample S2, no organic matter was released (remaining at zero levels), confirming that the stability of the dye-zeolite bond in this sample did not induce a decomposition process. Detailed Implementation

[0016] As anticipated above, the inventors of this invention, after extensive experimentation, discovered that dye-exchanged zeolite markers obtained through cation exchange reactions between zeolite and dyes are more stable than other zeolite-based markers known in the art in which the dye is only adsorbed onto the zeolite.

[0017] Therefore, the present invention relates to zeolite markers comprising dye exchange of zeolite and organic cationic dyes, wherein the markers are obtained by a cation exchange reaction between at least one cation of zeolite and at least one cation of organic cationic dye.

[0018] As will be apparent from the experimental section of this disclosure, the inventors discovered that the hole size is to Zeolites are particularly advantageous because they allow dyes to bind more efficiently to the zeolite and allow for better process yields. Surface area and porosity analysis were performed using a Micromeritics BET instrument. Prior to analysis, the samples were pretreated by degassing in a turbine vacuum at 180 °C, which allowed the removal of physically bound impurities from the material being analyzed. Analysis was then continued using CO2 for LTA (at -20 °C) or Ar for other zeolites (at -186 °C). The Dubinin Astakhov model was used to calculate the micropore surface area, while the Saito Foley model or NLDFT model was used to calculate the pore size.

[0019] Another important feature of the markers obtainable according to the invention is that they still allow for effective detection despite the relatively low dye / zeolite weight ratio (see samples S1 to S4, Table 1). Surprisingly, even when the weight ratio of dye to zeolite is 0.05% to 1% wt%, preferably 0.1% to 0.5% wt% (inclusive), the markers still allow for effective detection without altering the surface properties of the zeolite.

[0020] Therefore, the present invention relates to zeolite markers for dye exchange comprising zeolite and dye, wherein:

[0021] -Zeolite is characterized by its pore size. to

[0022] - The dye is an organic cationic molecule, and

[0023] - The amount of dye is 0.05% to 1% by weight relative to the weight of zeolite.

[0024] The zeolite suitable for the purposes of this invention is a zeolite commonly known in the art, provided that its pore size is [specific value missing]. to Preferably, the zeolite is octahedral zeolite (FAU) or mordenite (MOR).

[0025] The dye is a colorimetric dye commonly known in the art, preferably an organic cationic dye. Preferably, the dye is rhodamine or a derivative thereof, and more preferably, the dye is selected from the following: rhodamine B, tetramethylrhodamine isothiocyanate-dextran, rhodamine 6G, rhodamine B isothiocyanate, rhodamine perchlorate 19, and other rhodamine derivatives.

[0026] According to any embodiment of the invention, the zeolite is composed of X 90Value (where X) 90 The average particle size (characterized by a powder form, where 90% of the particles in the sample are contained within a given range of spherical diameters, based on volume) is 0.5 μm to 50 μm, preferably 0.5 μm to 20 μm.

[0027] One of the additional advantages associated with the markers is the possibility of further functionalization and activation of the zeolite surface, as the dyes are effectively bound to the interior of the zeolite.

[0028] In fact, in a preferred embodiment of the invention, the zeolite surface of the marker is modified with alkoxysilanes such as (3-aminopropyl)trimethoxysilane, (3-aminopropyl)triethoxysilane, N-trimethoxysilylpropyl-N,N,N-trimethylammonium chloride, octadecyldimethyl(3-trimethoxysilylpropyl)ammonium chloride, tetradecyldimethyl(3-trimethoxysilylpropyl)ammonium chloride, n,n-decyl-N-methyl-N-(3-trimethoxysilylpropyl)ammonium chloride, and s-(trimethoxysilylpropyl)isothiourea. The alkoxysilanes include chlorides, 3-(trihydroxymethsilyl)propyldimethyloctadecylammonium chloride, hydroxy-terminated silsesquioxanes 3-(dimethyloctadecylammonio)propyl, and (3-epoxypropoxypropyl)trimethoxysilanes. Modification with alkoxysilanes is achieved through hydrolysis and condensation. Preferably, the alkoxysilane derivative or alkoxysilane moiety is present in an amount from 1% to 40% by weight relative to the weight of the zeolite. The silane moiety can then be utilized due to its inherent properties or used as a linking group for further reaction or polymerization steps.

[0029] Dye-exchange zeolite markers according to any embodiment disclosed herein can also be dispersed in a polymer matrix to obtain an optically active composition.

[0030] Therefore, the present invention also relates to compositions comprising zeolite markers for dye exchange according to any embodiment disclosed herein and polymers or polymer matrices. The polymer matrix is ​​characterized by the absence of excitation and emission characteristics (peaks and / or more complex spectral features resulting from a general increase in absorption and / or emission) that could interfere with the level of excitation or emission of the marker. Specifically, since the dye excitation and emission peaks of rhodamine or its derivatives are concentrated at 560 nm and 580 nm, respectively, and considering a buffer spectral region defined within ±100 nm, a suitable polymer matrix is ​​characterized by the absence of excitation and emission characteristics in the range of 460 nm to 680 nm.

[0031] In a preferred embodiment, the polymer matrix is ​​selected from the following: polyethylene (PE); polypropylene (PP); polystyrene (PS); polyethylene terephthalate (PET); acrylonitrile butadiene styrene (ABS) and its copolymers and functionalized polymers; acrylic resins; acrylic-styrene, vinyl and alkyl copolymers; urethane-acrylic resins; aliphatic-urethane; urethane; polyurethane; epoxy resins; siloxanes and polysiloxanes; phenolic resins; poly[ethylene-copoly-(vinyl alcohol)] (EVOH); poly(vinyl alcohol) (PVAL); poly(lactic acid-copoly-glycolic acid) (PLGA); polyethylene glycol (PEG); poly(vinyl acetate) (PVAC); waterborne or water-reducible latex; polylactic acid (PLA); aliphatic / aromatic copolyesters, preferably polybutylene adipate (PBAT) and poly(butylene sebacic acid-copoly-terephthalate) (PBSeT), poly(butylene succinate-copoly-terephthalate) (PBST); aliphatic copolyesters derived from 1,4-butanediol and carboxylic acids, preferably poly(butylene succinate) (PBS) and polybutylene adipate succinate (PBSA); polyhydroxy fatty acid esters (PHA), preferably polyhydroxybutyrate (PHB), poly(hydroxybutyrate-copoly-hydroxyvalerate) (PHBV), polyhydroxybutyrate-hexanoate (PHBH); natural polymers, particularly polysaccharide polymers, such as chitosan, sodium alginate and starch or modified starch; and mixtures thereof. Preferred examples of polymer blends are blends of polylactic acid (PLA) and polyhydroxybutyrate / polyhydroxyvalerate (PHBV), or blends of polyvinyl alcohol (PVOH) and hydroxypropyl starch ether (STARCH).

[0032] In the obtained active composition, the dye-exchange zeolite marker is preferably present in an amount of 0.1% to 10% by weight relative to the weight of the polymer matrix.

[0033] In another embodiment, one or more additional components (e.g., fillers) are added to the composition, preferably in an amount of 0.1% to 20% by weight relative to the polymer matrix. The additional components may be selected, for example, from the following: hydrotalcite, zirconium phosphate, porphyrin, graphene and other two-dimensional crystals, zeolites, halloysite, graphene oxide, metal-organic frameworks (MOFs), organic beads, cellulose and antioxidant capsules, self-assembled proteins, ester-terminated polyamides, tert-amide-terminated polyamides, polyether polyamides, polyalkylene oxide-terminated polyamides, and mixtures thereof.

[0034] As will become apparent from the following non-limiting examples, the dye-exchange zeolite of the present invention and the polymer compositions comprising therein have been shown to have effective optical activity.

[0035] Therefore, the present invention also relates to the use of the dye-exchanged zeolite or polymer composition containing it as a detectable marker.

[0036] As will be apparent to those skilled in the art, the dye-exchange zeolite or polymer composition of the present invention can be embedded or coated onto articles (e.g., packaging, fabrics, general plastic articles, etc.) to make the article itself or at least a portion thereof detectable.

[0037] Therefore, the present invention also relates to articles or articles that at least partially comprise, embed, or coat with a dye-exchange zeolite or polymer composition according to any embodiment disclosed herein, preferably selected from packaging, fabrics, clothing, devices (e.g., medical devices), optical tags, marking components, and anti-counterfeiting elements.

[0038] In view of the above, compositions comprising dye-exchange zeolites according to any embodiment of the invention may be processed into coatings, films, varnishes, frames, three-dimensional elements, pellets or flakes, or generally into any other form suitable for the intended purpose.

[0039] The markers can be used as is or included in the polymer matrix as disclosed above to obtain optically active compositions.

[0040] Several methods can be used to prepare polymer / zeolite composites, such as in-situ polymerization, polymer dissolution and mixing, extrusion, melt blending or other molding processes (e.g. injection, transfer, compression, foaming, thermoforming, film blow molding).

[0041] As will be apparent from the following experimental section, the present invention also relates to methods for preparing polymer compositions comprising dye-exchanged zeolite markers according to any embodiment disclosed herein by means of in-situ polymerization, polymer dissolution and mixing, or melt blending, and to compositions that can be obtained therefrom.

[0042] Experimental Section

[0043] The invention will be described in more detail below with reference to the following non-limiting examples. The appended claims cover modifications or variations of the embodiments illustrated herein that will be apparent to those skilled in the art.

[0044] Preparation of Rhodamine-exchanged zeolite markers (samples S1 to S6 and counterexample C1)

[0045] 0.05 g to 1.25 g of Rhodamine B (RhB) or RhB-glucan (both from Sigma-Aldrich) were dissolved in 100 mL of distilled water. Then, 5 g of zeolite was added to the mixture, and the pH was adjusted to 6 using HCl (1 M) solution. The mixture was stirred in the dark using a laboratory magnetic stirrer at room temperature for 24 hours. The resulting complex was then purified by filtration. Purification involved thoroughly washing the powder with distilled water until the collected filtrate appeared completely clear. The obtained Rhodamine-exchanged complex was dried overnight in an oven at 80 °C.

[0046] Table 1

[0047]

[0048] The ion exchange reaction (C1) of 0.25 g RhB with LTA zeolite resulted in a very low Rhodamine B content (0.02 wt%) in LTA zeolite, making the sample unsuitable for use as a marker.

[0049] Preparation of counterexample C2

[0050] 0.25 g of Rhodamine B (RhB) was mechanically mixed with 5 g of zeolite to ensure effective dispersion of the different materials in powder form. The resulting mixture was then dried overnight in an oven at 80°C.

[0051] Preparation of counterexample C3

[0052] 0.25 g of 9-(diethylamino)-5H-benzo[a]phene Azine-5-one (alternative label NR) was dissolved in 100 mL of dimethyl sulfoxide. Then, 5 g of zeolite was added to the mixture. The mixture was stirred in the dark using a laboratory magnetic stirrer at room temperature for 24 hours. The resulting complex was then purified by filtration. Purification involved thoroughly washing the powder with distilled water until the collected filtrate appeared completely clear. The obtained exchanged complex was dried overnight in an oven at 80 °C.

[0053] Preparation of counterexample C4

[0054] 0.25 g of fluorescein 5(6)-isothiocyanate (the alternative marker FITC) was dissolved in 100 mL of distilled water. Then, 5 g of zeolite was added to the mixture. The mixture was stirred in the dark using a laboratory magnetic stirrer at room temperature for 24 hours. The resulting complex was then purified by filtration. Purification involved thoroughly washing the powder with distilled water until the collected filtrate appeared completely clear. The resulting exchanged complex was dried overnight in an oven at 80 °C.

[0055] Preparation of counterexample C5

[0056] 3-Aminopropyl)triethoxysilane-rhodamine (APTES-RhB) molecules were prepared and then attached to a zeolite surface. The synthesis followed the protocol described in T. Nedelcev et al. / Dyes and Pigments 76 (2008) 550e556. Briefly, rhodamine B (0.002 mol, 0.96 g) was dissolved in chloroform (30 mL). The solution was stirred and heated to the boiling point of chloroform (61.2 °C). APTES (from ABCR) (0.002 mol, 0.465 mL) was then added dropwise to the rhodamine B solution with stirring. The reaction was stopped after 30 minutes, and the chloroform was removed from the reaction mixture using a rotary evaporator. The remaining material (silanized rhodamine, approximately 1.3 g) was dried in an oven at 60 °C.

[0057] Release tests on samples S1 to S6 and counterexamples C1 to C4

[0058] To verify that in dye-exchanged zeolite labels, the dye is effectively bound to the zeolite and therefore not released upon contact with solvent or exposure to higher temperatures, the label dispersion can be directly studied. 22.4 mg of selected samples (S1 to S6) or counterexamples (C1 to C4) were dispersed in 20 g of solvent. The samples were vigorously stirred at room temperature (RT) and allowed to settle for the following 24 hours. The appearance of the supernatant was analyzed by simple visual observation and compared with a reference colored sample (R1) obtained by dissolving 1.12 mg (2,34E-06 mol) RhB powder in 20 g of solvent. The list of solvents used included distilled water, acetone, dimethyl sulfoxide, tetrahydrofuran, chloroform, and dichloromethane (DCM). As reported in Table 2, the completely transparent dispersions for all solvents used confirmed the absence of released dye.

[0059] As an additional test, the prepared sample dispersion was vigorously stirred at 50°C for 10 minutes and then allowed to settle for the following 24 hours. Under these conditions, the appearance of the sample supernatant was analyzed by simple visual observation and compared with a reference colored dye sample. A completely transparent dispersion confirmed the absence of released dye, and the absence of a spectrophotometric signal associated with the dye confirmed its absence. As reported in Table 2, the stability results observed for the room temperature sample were confirmed after the heat treatment.

[0060] The dispersions prepared as reported above were further analyzed by UV-Vis spectrophotometry. Calibration curves were determined for each solvent, and a detection limit (DL) of 1 ppm was established. The effects of parameters such as solvent properties, temperature, and stirring time were investigated. The results are reported in Table 3, and the DL for each solvent was determined without detecting any absorption peaks, with a calculated relative error of 15%.

[0061] Table 2. Dissolution of the marker in the selected solvent (× = no dye release; √ = dye release). Tests were performed at room temperature and after 10 minutes at 50°C; observations were made after 24 hours.

[0062]

[0063]

[0064] Table 3. Dye release of the samples in selected solvents.

[0065]

[0066]

[0067] To confirm the increased stability of the marker prepared according to the present invention, samples C2 and S2 were further exposed to a heat treatment simulating polymer processing (characterized by rapid heating to 250 °C (50 °C / min) and isothermal for 5 minutes) in a thermogravimetric mass spectrometry (TG-MS) instrument to determine traces of organic matter from the decomposition of Rhodamine B. As reported in Figure 1, some organic matter was clearly identified when sample C2 underwent the above treatment, while for sample S2, the organic matter remained at zero level.

[0068] Contact angle test

[0069] Contact angle measurement is a technique used to determine the wetting characteristics of a droplet on a solid surface. The contact angle is the angle formed between the tangent at the three-phase contact line of the droplet and the solid surface.

[0070] Initially, a target solid substrate is prepared to measure wetting behavior. In this case, the substrate is a zeolite powder pellet. Then, small droplets of the substance under study are carefully placed onto the solid surface using a syringe, micropipette, or other precise dispensing method.

[0071] Finally, a high-resolution camera captures images of the droplets on the solid surface from a suitable angle. For zeolite pellets, this acquisition must be extremely fast, taking less than one second, compared to standard methods. The acquired images are then processed using specialized software to analyze the droplet shape and determine the contact angle.

[0072] If water is used as the liquid probe, the sample is labeled as hydrophilic (polar surface, strongly interacting with H2O) when the contact angle is <90°, and as hydrophobic when the contact angle is >90°.

[0073] Ordinary zeolite surfaces are hydrophilic, but when the powder surface is functionalized with organic molecules, it can become hydrophobic.

[0074] Contact angle analysis was performed on samples S2 and counterexample C5, and the relevant results reported in Table 4 demonstrate that, according to the procedure of the present invention, rhodamine can be incorporated into the pores of zeolite, while following procedures known in the art, rhodamine is bonded to the outer surface.

[0075] Therefore, in contrast to hydrophobic zeolites such as C5, the zeolites disclosed herein that contain rhodamine within their pores are more readily integrated into other matrices / compositions, and in addition, the zeolites are characterized by the ability to further interact or functionalize on their surfaces.

[0076] Table 4. Contact Angle Values

[0077] serial number sample <![CDATA[Contact angle H2O (°)]]> S2 FAU5.1_RhB_13 <![CDATA[ 16.5±1.6 <!-- 8 -->]]> C5 FAU5.1_APTES-RhB <![CDATA[ 99.7±3.8 ]]>

[0078] Preparation method for dispersing dye-exchange zeolite markers in a polymer matrix to obtain optically active compositions Law.

[0079] Several methods can be used to prepare polymer / zeolite composites, such as in-situ polymerization, polymer dissolution and mixing, or melt blending.

[0080] Preparation via in-situ polymerization is based on the following first step: the formulation of a polymer precursor, followed by the introduction of a dye using efficient techniques to obtain a fine dispersion. After obtaining a homogeneous dispersion, the liquid formulation is applied to a support, where the polymerization process is promoted by activation with an initiator. Different activation fields can be employed depending on the initiator characteristics and the formulation's chemical composition. Typical methods are based on thermal processing or UV irradiation.

[0081] The solution mixing method comprises four steps: dissolving the polymer matrix in a suitable solvent at room temperature or elevated temperature, dispersing the zeolite in the solvent, mixing the two solutions by mechanical stirring or tip / bath sonication, and finally precipitating or casting the mixture to obtain a film after solvent evaporation.

[0082] Melt blending is a common technique for manufacturing thermoplastic / zeolite composites. It utilizes high temperatures and high shear forces to disperse the zeolite and is compatible with industrial processes. Depending on the desired final form / shape of the composite, the bulk material can be processed using various post-extrusion techniques (e.g., film forming, injection molding, compression molding, melt spinning).

[0083] The following reports different examples of different preparation methods according to the present invention:

[0084] Example Preparation method AC 1 to 5 In-situ polymerization AC 6 to 14 Polymer Dissolution and Mixing AC 15 to 18 melt blending

[0085] Sample AC 1. A film of the active composition was prepared by mixing 1.5 g of polyethylene glycol dimethacrylate (PEGDMA) with 0.07 g of ESACURE ONE (bifunctional oligomeric α-hydroxy ketone) from IGM resin as a photoinitiator for generating free radicals. After the photoinitiator was completely dissolved, 0.015 g of rhodamine-zeolite sample S2 was added to the formulation at room temperature and mechanically mixed for 30 minutes. The obtained formulation was spread on a glass substrate to a thickness of 50 μm using a doctor blade and subjected to irradiation of 100 mW / cm². 2 The UV lamp was focused at 365nm for 15 seconds (radiation dose of 1.5J / cm). 2 To facilitate the polymerization process, a label-free reference PEGDMA (UV-cured) film was prepared using the same experimental protocol. The polymerization process was carried out in a glove box environment under an inert gas flux.

[0086] Sample AC 2. A film of the active composition was prepared by mixing 1.5 g of polyethylene glycol dimethacrylate with 0.07 g of azobisisobutyronitrile (AIBN) from Sigma Aldrich as a thermal initiator for generating free radicals. After the initiator was completely dissolved, 0.015 g of rhodamine-zeolite sample S2 was added to the formulation at room temperature and mechanically mixed for 30 min. The obtained formulation was spread on a glass substrate to a thickness of 50 μm using a doctor blade, and the polymerization process was promoted by heating the sample at 80 °C for 30 min. The polymerization process was carried out in a glove box environment under an inert gas flux.

[0087] A reference PEGDMA (thermosetting) film without markers was also prepared using the same experimental protocol.

[0088] Sample AC 3. By using 0.9 grams of Epikote from Hexion TM 862 (bisphenol F resin) with 0.15 g of Epon 8111 (epoxy acrylate resin) from Hexion and 0.38 g of Epikote TMA film of the active composition was prepared by mixing 03161 (rubber-modified bisphenol A resin). The obtained formulation was vigorously stirred for 1 hour by mechanical mixing to obtain a homogeneous solution. Then, 0.08 g of triarylsulfonium hexafluoroantimonate as a cationic initiator was added and dissolved by mechanical stirring for 30 minutes. After the initiator was completely dissolved, 0.015 g of rhodamine-zeolite sample S2 was added to the formulation at room temperature and mechanical mixing was continued for another 30 minutes. The obtained formulation was spread on a glass substrate to a thickness of 50 μm using a doctor blade and subjected to an irradiation of 100 mW / cm². 2 UV treatment (where λ = 365 nm) was applied for 120 seconds to promote the polymerization process.

[0089] A label-free reference membrane based on bisphenol F diglycidyl ether (DGEBF) was also prepared using the same experimental protocol.

[0090] Sample AC 4. By using 1.35 g of Sylgard from DOW TM A film of the active composition was prepared by mixing part 184A (polydimethylsiloxane, PDMS) with 0.15 g of part 184B (dimethyl, methylhydrosiloxane copolymer) of DOW as a crosslinking agent for 10 minutes. Then, 0.015 g of rhodamine-zeolite sample S2 was added to the formulation at room temperature, and mechanical mixing was continued for another 10 minutes. After obtaining a homogeneous dispersion, a degassing process under vacuum was carried out for 15 minutes. The obtained formulation was spread onto a glass substrate to a thickness of 50 μm using a doctor blade, and the polymerization process was promoted by heating the sample at 100 °C for 30 minutes.

[0091] A reference PDMS membrane without label was also prepared using the same experimental protocol.

[0092] Sample AC 5. A membrane of the active composition was prepared by mixing 1.45 g of SunChemical's COMPOSTER LAM ADH (aliphatic polyisocyanate-based polyurethane, PU) with 0.05 g of alcohol dehydrogenase catalyst. Then, 0.015 g of Rhodamine-zeolite sample S2 was added at room temperature, and the dispersion was stirred by mechanical mixing for 15 minutes. The obtained formulation was spread onto a glass substrate to a thickness of 50 μm using a spatula, and the crosslinking reaction was promoted at room temperature.

[0093] A reference PU film without markers was also prepared using the same experimental protocol.

[0094] Sample AC 6. 1.5g of LyondellBasell 2420 grade low-density polyethylene (LDPE) was dissolved in 8.5 g of toluene at a boiling temperature of 110 °C. After the polymer was dissolved, 0.015 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by acoustic treatment in a bath for 30 minutes at room temperature, followed by vigorous mechanical mixing for 1 hour.

[0095] The obtained formulation was spread onto a Teflon foil to a thickness of 50 micrometers using a doctor blade, and solvent evaporation was promoted at 50°C. A composite membrane containing 1% by weight of the labeled material in the polymer matrix was obtained. A reference LDPE membrane without the labeled material was also prepared using the same experimental protocol.

[0096] Sample AC 7. 1.5g of Versalis N1910 (ENI) grade atactic polystyrene (PS) was dissolved in 8.5 g of toluene at a boiling temperature of 110 °C. After polymer dissolution, 0.015 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by acoustic treatment in a bath for 30 minutes at room temperature, followed by vigorous mechanical mixing for 1 hour. The obtained formulation was spread onto Teflon foil to a thickness of 50 μm using a spatula, and solvent evaporation was promoted at 50 °C. A composite membrane containing 1% by weight of the labeled polymer matrix was obtained. A reference PS membrane without the labeled polymer was also prepared using the same experimental protocol.

[0097] Sample AC 8. 1.0 g of GoodFellow polylactic acid (PLA) (MFR=8) was dissolved in 9.0 g of chloroform at a boiling temperature of 61 °C. After the polymer was dissolved, 0.01 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by acoustic treatment in a bath for 30 minutes at room temperature, followed by vigorous mechanical stirring for 1 hour. The obtained formulation was spread on a Teflon foil to a thickness of 50 μm using a spatula, and solvent evaporation was promoted at 40 °C. A composite membrane containing 1% by weight of the label in the polymer matrix was obtained. A reference PLA membrane without the label was also prepared using the same experimental protocol.

[0098] Sample AC 9. 1.0 g of GoodFellow polyhydroxybutyrate (PHB) was dissolved in 20.0 g of chloroform at a boiling temperature of 61 °C. After the polymer was dissolved, 0.03 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by acoustic treatment in a bath for 30 minutes at room temperature, followed by vigorous mechanical mixing for 1 hour. The obtained formulation was spread on a Teflon foil to a thickness of 50 μm using a spatula, and solvent evaporation was promoted at 40 °C. A composite membrane containing 3% by weight of the label in the polymer matrix was obtained. A reference PHB membrane without the label was also prepared using the same experimental protocol.

[0099] Sample AC 10. 1.0 g of GoodFellow's 2% polyhydroxybutyrate / polyhydroxyvalerate (PHBV) was dissolved in 20.0 g of chloroform at a boiling temperature of 61 °C. After the polymer was dissolved, 0.03 g of Rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by acoustic treatment in a bath for 30 minutes at room temperature, followed by vigorous mechanical mixing for 1 hour. The resulting formulation was spread onto Teflon foil to a thickness of 50 μm using a spatula, and solvent evaporation was promoted at 40 °C. A composite membrane containing 3% by weight of the labeled polymer matrix was obtained. A label-free reference PHBV membrane was also prepared using the same experimental protocol.

[0100] Sample AC 11. 1.0g of Kuraray AQ-4104 grade polyvinyl alcohol (PVOH) was dissolved in 9.0 g of distilled water at a boiling temperature of 100 °C. After the polymer was dissolved, 0.01 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by acoustic treatment in a bath for 30 minutes at room temperature, followed by vigorous mechanical mixing for 1 hour. The obtained formulation was spread onto a glass substrate to a thickness of 50 μm using a spatula, and water evaporation was promoted at 50 °C. A composite membrane containing 1% by weight of the labeled polymer matrix was obtained. A reference PVOH membrane without the labeled polymer was also prepared using the same experimental protocol.

[0101] Sample AC 12. 1.0 g of SOLAM's SOLCOAT P85 grade hydroxypropyl starch ether (STARCH) was dissolved in 9.0 g of distilled water at a boiling temperature of 100 °C. After the polymer was dissolved, 0.01 g of Rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by acoustic treatment in a bath for 30 minutes at room temperature, followed by vigorous mechanical mixing for 1 hour. The obtained formulation was spread onto a glass substrate to a thickness of 50 μm using a spatula, and water evaporation was promoted at 40 °C. A composite membrane containing 1% by weight of the label in the polymer matrix was obtained. A label-free reference STARCH membrane was also prepared using the same experimental protocol.

[0102] Example AC 13 (Blend 1). 0.7 g of GoodFellow polylactic acid (PLA) (MFR = 8) and 0.3 g of GoodFellow polyhydroxybutyrate / polyhydroxyvalerate 2% (PHBV) were dissolved in 18.0 g of chloroform at a boiling temperature of 61 °C. After the polymer was dissolved, 0.05 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by acoustic treatment in a bath for 30 minutes at room temperature, followed by vigorous mechanical stirring for 1 hour. After casting, a composite membrane containing 3% by weight of the label in the polymer matrix was obtained. A label-free reference PLA / PHBV membrane was also prepared using the same experimental protocol.

[0103] Example AC 14 (blend 2). 0.7 g of Kuraray was added under vigorous stirring. AQ-4104 grade polyvinyl alcohol (PVOH) and 0.3 g of SOLAM's SOLCOAT P85 grade hydroxypropyl starch ether (STARCH) were dissolved in 9.0 g of distilled water at 90 °C. After the polymer was completely dissolved, 0.01 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature (RT), and the dispersion was mixed by acoustic treatment in a bath for 30 minutes at room temperature, followed by vigorous mechanical mixing for 1 hour at room temperature. The resulting formulation was spread onto a glass substrate to a thickness of 50 μm using a spatula, and water evaporation was promoted at 50 °C. A label-free reference PVOH / STARCH membrane was also prepared using the same experimental protocol.

[0104] Example AC 15. 49 g of low-density polyethylene powder (≤400 μm) purchased from Alfa Aesar was melt-blended with 1 g of rhodamine-zeolite (sample S2) for 5 minutes using a laboratory two-roll open mixing mill (Battaggion). The rolling conditions were: front roll temperature = 130°C; back roll temperature = 80°C; rolling speed = 33 rpm. The resulting composite material was compressed for 5 minutes using a laboratory press (Gibitre Instruments) at P = 230 bar and T = 175°C to obtain a sheet (thickness ≈ 200 μm) with 2% by weight of the marker. A reference polyethylene sheet without the marker was also produced following the same experimental protocol.

[0105] Example AC 16. 49 g of polylactic acid (NatureWorks 2003D grade) and 1 g of rhodamine-zeolite (sample S2) were melt-blended for 5 minutes using a laboratory two-roll open mixing mill (Battaggion). The rolling conditions were: front roll temperature = 155°C; back roll temperature = 125°C; rolling speed = 33 rpm. The resulting composite material was compressed for 5 minutes using a laboratory press (Gibitre Instruments) at P = 230 bar and T = 190°C to obtain a sheet (thickness ≈ 200 μm) with 2% by weight of the marker. A reference polylactic acid sheet without the marker was also produced following the same experimental protocol.

[0106] Example AC 17. 48.5 g of Good Fellow's 2% polyhydroxybutyrate / polyhydroxyvalerate (PHBV) was melt-blended with 1.5 g of rhodamine-zeolite (sample S2) for 5 minutes using a laboratory two-roll open mixing mill (Battaggion). The rolling conditions were: front roll temperature = 170°C; back roll temperature = 145°C; rolling speed = 33 rpm. The resulting composite was compressed for 5 minutes using a laboratory press (Gibitre Instruments) at P = 230 bar and T = 190°C to obtain a sheet (thickness ≈ 200 μm) with 3% by weight of the marker. A reference PHBV sheet without the marker was also produced following the same experimental protocol.

[0107] Example AC 18

[0108] Using a laboratory benchtop two-roll mill (LabTech Engineering), 98g of acrylonitrile butadiene styrene (ABS) produced by INEOSS TYROLUTION was processed. GP-22 grade ABS was composited with 2 g of rhodamine-zeolite (sample S5) by melt blending for 5 minutes. The rolling process conditions were: front roll temperature = 175°C; back roll temperature = 170°C; rolling speed = 10 rpm. The resulting composite containing 2 wt% marker S5 was formed into sheets (500 μm thick). A reference ABS sheet without marker was produced following the same preparation protocol.

[0109] Table 4 below summarizes examples of the preparation:

[0110]

[0111]

[0112] Optical characterization of markers and matrix.

[0113] Equipment Description. Using Horiba Measurements were performed using a Plus fluorescence spectrophotometer. A continuous light source P focused on the entrance slit of the excitation monochromator was employed. o =150W ozone-free xenon arc lamp. The instrument is based on two Czerny-Turner monochromators that disperse the incident light through their reflection gratings. Spectra are obtained by rotating the gratings and recording the intensity values ​​at various wavelengths. Each monochromator's inlet and outlet ports include continuously adjustable slits to control the spectral resolution and intensity of the fluorescence signal recorded by the photomultiplier tube. A solid sample holder mounted on an adjustable goniometer is used to test polymer products in the form of labeled films or plates. A sample setup with a 60° angle between the incident beam and the specularly reflected beam prevents the excitation beam from entering the emission slit, thus avoiding stray light interference. FluorEssence is used. TM Analysis and management software is used to acquire and process data.

[0114] Description of the sample characterization scheme.

[0115] The presence of dye within the polymer matrix was detected by comparing the excitation and emission peaks of the labeled polymer matrix with those of a reference sample (a polymer matrix without the labeled dye) and a pure labeled polymer matrix. The sample performance was studied as the ratio between the fluorescence intensity I of the active composition excited at 540 nm and the fluorescence intensity I0 of the pure polymer matrix without the dye excited at 540 nm, taking dye fluorescence into account. Depending on the protocol used, the presence of the labeled dye was considered detectable when the I / I0 ratio was greater than 2. Recorded values ​​for all tested samples are reported in Table 5 below.

[0116] Table 5

[0117]

[0118]

Claims

1. A zeolite marker for dye exchange, comprising zeolite and dye, wherein: a) The zeolite is an octahedral zeolite (FAU) or mordenite (MOR), characterized in that the pore size is determined using a Micromeritics BET instrument. to b) The dye is an organic cationic molecule selected from the following: Rhodamine B, tetramethylrhodamine isothiocyanate-dextran, Rhodamine 6G, Rhodamine B isothiocyanate, Rhodamine 19 perchlorate, and other Rhodamine derivatives, and c) The amount of dye is 0.05% to 1% by weight relative to the weight of the zeolite.

2. The dye-exchange zeolite marker according to claim 1, wherein the amount of dye is 0.1% to 0.5% by weight relative to the weight of the zeolite.

3. The dye-exchange zeolite marker according to any one of the preceding claims, wherein the zeolite is formed by X 90 The value characterizes the average particle size of powders ranging from 0.5 μm to 50 μm, where X 90 This indicates that, based on volume, 90% of the particles in the sample are contained within a given range of spherical diameters.

4. The zeolite marker for dye exchange according to claim 3, wherein the average particle size is characterized by X 90 The value ranges from 0.5 μm to 20 μm.

5. The dye-exchange zeolite marker according to claim 1 or 2, wherein the zeolite comprises a surface modified or functionalized with an alkoxysilane derivative.

6. The dye-exchange zeolite marker according to claim 5, wherein the alkoxysilane derivative portion is present in an amount of 1% to 40% by weight relative to the weight of the zeolite.

7. The dye-exchange zeolite marker according to claim 1 or 2 can be obtained by a cation exchange reaction between at least one cation of the zeolite and at least one cation of the dye.

8. A composition comprising a dye-exchanged zeolite marker according to any one of the preceding claims dispersed in a polymer matrix, wherein the polymer matrix is ​​selected from polyethylene (PE); polypropylene (PP); polystyrene (PS); polyethylene terephthalate (PET); acrylonitrile butadiene styrene (ABS) and copolymers and functionalized polymers thereof; acrylic resins; acrylic-styrene; acrylic-vinyl and alkyl copolymers; urethane-acrylic resins; aliphatic-urethane; urethane; polyurethane; epoxy resins; siloxanes and polysiloxanes; phenolic resins; poly(ethylene-copolymers) [(vinyl alcohol)](EVOH); poly(vinyl alcohol) (PVAL); poly(lactic acid-copoly-glycolic acid) (PLGA); polyethylene glycol (PEG); poly(vinyl acetate) (PVAC); aqueous or water-dilutable latex; polylactic acid (PLA); polybutylene adipate terephthalate (PBAT); poly(butylene sebacate-copoly-terephthalate) (PBSeT); poly(butylene succinate-copoly-terephthalate) (PBST); aliphatic copolyesters derived from 1,4-butanediol and carboxylic acids; polyhydroxyalkanoates (PHA); natural polymers; and mixtures thereof.

9. The composition of claim 8, wherein the aliphatic copolyester derived from 1,4-butanediol and carboxylic acid is selected from poly(butylene succinate) (PBS) and polybutylene adipate succinate (PBSA).

10. The composition according to claim 8, wherein the polyhydroxyalkanoate (PHA) is selected from polyhydroxybutyrate (PHB), poly(hydroxybutyrate-copolymer-hydroxyvalerate) (PHBV), and polyhydroxybutyrate-hexanoate (PHBH).

11. The composition according to claim 8, wherein the natural polymer is selected from chitosan, sodium alginate, starch, and modified starch.

12. The composition according to claim 8, wherein the mixture is selected from blends of polylactic acid (PLA) and polyhydroxybutyrate / polyhydroxyvalerate (PHBV), and blends of polyvinyl alcohol (PVOH) and hydroxypropyl starch ether (STARCH).

13. The composition of claim 8, wherein the dye-exchanged zeolite marker is present in an amount of 0.1% to 10% by weight relative to the polymer matrix.

14. The composition according to any one of claims 8 to 13 further comprises a filler in an amount of 0.1% to 20% by weight relative to the polymer matrix.

15. The composition of claim 14, wherein the filler is selected from: hydrotalcite, zirconium phosphate, porphyrin, graphene and other two-dimensional crystals, zeolite, halloysite, graphene oxide, metal-organic frameworks (MOFs), organic beads, cellulose and antioxidant capsules, self-assembled proteins, ester-terminated polyamides, tert-amide-terminated polyamides, polyether polyamides, polyalkylene oxide-terminated polyamides, and mixtures thereof.

16. The composition according to any one of claims 8 to 13, wherein the polymer matrix is ​​processed into the form of a coating, film, varnish, frame, three-dimensional element, pellet or sheet.

17. Use of the dye-exchange zeolite according to any one of claims 1 to 7 or the composition according to any one of claims 8 to 16 as a detectable marker.

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