BR102013008369A2 - PROCESSES FOR PREPARING A PT3MA AND PBS CONDUCTING POLYMERIC MIXTURE, A BIODEGRADABLE CONDUCTIVE MEMBRANE, A PT3MAIPVDFIZNSIO4: MN COMPOSITE, AND AN ELECTROLUMINESCENT DEVICE - Google Patents

Abstract

"processes for preparing a conductive polymer mixture of pt3ma and pbs, a biodegradable conductive membrane, a composite of pt3maipvdfiznsio4: mn, and an electroluminescent device". The present invention describes a process for preparing a poly (3-thiophene acetate methyl) and poly (butylene succinate) (pt3ma and pbs) conductive polymer mixture comprising dissolving poly (3-thiophene acetate) and poly (butylene). succinate). Additionally, the present invention relates to a process for preparing a biodegradable conductive membrane comprising the conductive polymer mixture of pt3ma and pbs. furthermore, the present invention relates to a process for preparing a conductive polymeric mixture of poly (3-thiophene methyl acetate) / poly (vinylidene fluoride) (pt3ma and pvdf), and a process for preparing a device electroluminescent compound comprising the conductive polymer mixture of pt3ma and pvdf.

Description

“PROCESSES FOR THE PREPARATION OF A CONDUCTIVE POLYMERIC MIXTURE OF PT3MA AND PBS, A BIODEGRADABLE CONDUCTIVE MEMBRANE, A COMPOSITE OF PT3MA / PVDF / ZNSIO ₄ : MN, AND AN ELECTRUMUMINESCENT DEVICE.

FIELD OF THE INVENTION

The present invention relates to the process of preparing conductive polymeric mixtures comprising Poly (methyl 3-thiophene acetate) and Poly (butylene succinate) (PT3MA and PBS), to the biodegradable conductive ultrafine membranes produced from said polymeric mixtures. In addition, the present invention relates to a composite of Poly (methyl 3-thiophene acetate) / Poly (vinylidene fluoride) / Manganese doped zinc silicate (PT3MA / PVDF / ZnSiO4: Mn) and films applicable to electroluminescent devices produced from said composites.

BACKGROUND OF THE INVENTION

Currently, a large part of the objects present in our lives are made up of polymers. Good mechanical properties, easy processability and low cost have been the main causes of the extensive use of polymers. However, polymers have not been restricted to basic everyday applications. Since the beginning of the 1980s, research involving 20 studies of their physical-chemical and electrical properties has contributed to technological advances in several areas, such as medicine and microelectronics.

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In this context, a very special class of polymers called conductive polymers has been investigated due to their good electrical properties. Polyanilines, polypyrroles and polythiophenes are some of the polymers studied for presenting good electrical conductivity. The conduction in these polymers occurs through the transport of charges along the polymeric chains by rearranging the double and simple connections of the jointed systems, when under the effect of an electric field. The manufacture of electronic devices with these polymers has increased in recent years, of which we can highlight the organic light-emitting diodes OLEDs, PLEDs polymeric light-emitting diodes, electroluminescent polymeric electronic devices and photovoltaic devices.

In search of the best polymer / polymer ratio for a polymeric mixture and polymer / inorganic material for a composite, research on the properties of these new materials has been carried out in order to investigate their chemical, mechanical, electrical and optical properties. These studies involving mixtures of polymers and inorganics aim to achieve a balance point in the properties of the final product so that it is suitable for its intended application. For example, a polymer poor in electrical conductivity, but with good mechanical property can become conductive if another polymer with the desired conductive property is added and mixed.

Several methods of polymerization of monomers are currently known, among which chemical synthesis, synthesis

3/50 electrochemistry and photochemical synthesis. The choice of method depends on the starting monomer, as not all undergo polymerization by both techniques. Polythiophene is a conductive polymer that can be synthesized by the 3 techniques.

The Poly (styrene succinate) polymer (PBS), better known by the trade name Polyester 4.4, belonging to the class of aliphatic polyesters is well known for its high ecological performance as biodegradable plastic.

In this sense, the preparation of a polymeric PBS / polythiophene mixture opens up the prospect of making a new material with conductive and biodegradable properties. The present invention, therefore, describes the obtaining of nanomembranes on ITO substrate by spinner using an intermediate layer of a polymer soluble in ethanol (Sacrifice Polymer) which was used to obtain nanomembranes from the polymeric mixture Poly (methyl 3-thiophene acetate) / Poly (styrene succinate) PT3MA / PBS.

The preparation of conductive membranes made up of polythiophenes and polyfluorides has been the subject of research by groups of researchers due to the combination, respectively, of their conductive and mechanical properties. Studies on polymeric mixtures of polymers obtained by template synthesis via electrochemical reaction of the conductive polymer or by reactive mixing technique on heating and cooling conditions have been reported in the literature.

In this sense, the photochemical synthesis of polythiophenes in aqueous solutions containing microporous matrices of vinylidene polyfluoride) appears as an option to increase the conductivity in polyfluorides, typically insulators, and

4/50 to obtain conductive membranes of this nature. Thus, the present invention describes reaction conditions of thiophene monomers in aqueous solution in the presence of light and their photochemical synthesis in polymeric PVDF matrices being the electrical behavior of their mixtures (Polithiophene / PVDF) evaluated by 5 electrical conductivity measures. The introduction of polymers in electronic devices, such as electroluminescent devices, has contributed to reduce costs in its manufacturing processes. These devices are made up of composites generally made up of a luminophore and a polymeric mixture of an isoiant matrix polymer with good mechanical properties and a conductive polymer. US patent 6004686, for example, describes the preparation of conductive electroluminescent material that includes a layer of luminophore particles coated with conductive inorganic oxide (ITO) unlike this device which uses polymers that increase its flexibility. US 2009/0212690, in turn, describes the construction 15 of flexible electroluminescent devices consisting of different layers: polymeric and emitter, unlike the technology of this device which uses only one layer with both constituents.

Thus, the manufacture of a device made up of the poly (vinylidene fluoride) / poly (3-thiophene methyl acetate / ZnSiO ^ Mn) composite opens up the prospect of obtaining a new type of electroluminescent device.

In parallel to the determination of the electrical properties of the polythene / PVDF mixtures, the present invention additionally describes the optical-electrical properties of devices containing monolayer films on substrate of

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ITO obtained by adding zinc silicate doped with manganese in solutions consisting of polymeric Polythiophene / PVDF mixtures.

Physics, chemistry and engineering are areas of applied science that carry out research with the objective of looking for new materials, especially polymeric ones, replacing those hitherto called conventional, such as metals and ceramics. The latter in general have good mechanical resistance properties, however in most cases they have low resistance, difficult processing and moldability in addition to high production costs. On the other hand, polymeric materials have differentiated properties such as lightness, transparency to light, moldability and high chemical resistance which, associated with great diversity and low production cost, become quite attractive industrially. Due to the semiconductor properties of some polymers, studies on the evaluation of their electrical properties have been carried out. Today 15 applications of these can be seen in photovoltaic cells, electroluminescent devices and electro, chemo and biosensors. These studies aim to replace traditional inorganic and metallic conductive materials with electroactive polymers. In piezoelectric transducers, Poly (vinylidene fluoride) (PVDF), its copolymers and hybrid materials (composites and polymeric mixtures) have replaced the 20 traditional zinc oxide and PZT electrodes.

In the construction of photovoltaic cells, polythiophenes and polyanilines have been used, respectively, as electroactive polymers to replace traditional silica and germanium electrodes.

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Studies on the enzymatic biodegradability of these polymers are currently being carried out. The biodegradable polymer Poli (butylene succinate) PBS is among the main polymers researched. Morphological and electrical conductivity studies of some polymer nanocomposites are cited in the literature.

Polythiophenes are members of a family of conductive polymers that have excellent conductive, electroluminescent and optical properties. Studies and research on these polymers have been carried out in order to solve the large number of problems encountered during their processing. The Poly 10 (3-alkyl-thiophenes), polythiophenes with branching in the 3 position of the main chain, stand out for containing hydrophilic groups that significantly increase their solubility in more polar solvents. The evaluation of the hydrophobicity and conformation of Poly (3-alkyl-thiophenes) side chains has been studied and reported in the literature due to the fact that some of these polymers have easy solubility in water. Studies involving conformational analysis and conductivity of Poly (3-alkylthiophenes) indicate the dependence of this property on the hydrophilic / hydrophobic character and on the hysterical effects present in its side chains.

The preparation of ultrafine membranes has recently been the subject of 20 research in the science and technology of nanomaterials. At the same time, numerous strategies to improve the stability and mechanical integrity of conductive polymers susceptible to p-type doping have been carried out due to their limitation as organic thin film, easily oxidized in the presence of oxygen and

7/50 poor in mechanical properties. This last feature limits its technological applications.

Ultrathin nanomembranes can currently be applied in the manufacture of separation nanomembranes, in the assembly of nanosensors and in the assembly of electrodes used in electrochemical determinations.

However, as can be seen, no state-of-the-art document describes or suggests a process for producing ultrafine membranes made up of 20:80, 80:20 and 50:50 polymeric mixtures of biodegradable polyester (poly butylene succinate) with poly polyethylene (Methyl 3-thiophene acetate), both obtained by chemical synthesis.

Poly (vinylidene fluoride) is a fluorinated polymer known for its good piezoelectric, mechanical and insulating properties. Easy moldability, inherent stability and high flexibility and hardness of its films are some of the good mechanical properties of the polymer. PVDF is a semicrystalline polymer (approximately 50% amorphous and 50% crystalline) consisting of respective units. Their chains have a linear distribution that provide the formation of permanent dipoles attributed to the difference in electronegativity between the fluorine and carbon atoms.

Its monomeric units can form macromolecular chains of up to 2000 units. The polymer is soluble in solvents such as dimethylformamide, dimethylacetamide, tetrahydrofuran, dimethyl sulfoxide, acetophenone, benzophenone and n-methyl-2-pyrrolidone.

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Luminescent materials composed of luminophores have been applied in the construction of digital displays and panels used in televisions and computers. The ZnSiO ^ .Mn luminophore has been used in many industrial applications as a green light emitting phosphor. The use of the material as a green component of plasma display panels has been proposed in the literature. The concentration of magnesium dopant has a fundamental role in the intensity of green light emission. However the short life span of the commercial ZnSÍO ₄ : Mn has limited its application in television sets.

Polymers are examples of low-cost alternative materials that can be used in the construction of electronic devices. The conducting polythiophene polymer is well known for its high electrical conductivity values when doped. The poly (vinylidene fluoride) PVDF, however, has an insulating character, but with good mechanical properties.

However, as can be seen, no prior art document describes or suggests monolayer electroluminescent devices consisting of a composite film consisting of the PVDF / P3TMA 80:20 polymeric mixture and ZnSiO ₄ : Mn luminophore, as described in the present invention.

BRIEF DESCRIPTION OF THE INVENTION

The present invention describes a process for preparing a polymeric conductive mixture of poly (methyl 3-thiophene acetate) and polyfutyl succinate) (PT3MA and PBS) comprising the dissolution of poly (methyl 3-thiophene acetate) and polyfutyl succinate), in the mass ratio in which the amount of PT3MA can

9/50 vary between 80 and 50, for a quantity of PBS varying between 20 and 50, with the preferred mass ratio between them being 80:20, in anhydrous chloroform containing a variable amount of ethanol between 0.5 and 1%, resulting in a solution with a variable concentration between 4% and 145 mg / ml, with the preferred concentration being around 5 mg / ml.

In addition, a process for preparing a biodegradable conductive membrane comprising the following steps is described in the present invention:

i) Preparation of an intermediate sacrifice layer by centrifugation (1), using poly (4-hydro-styrene) (PHS) as a sacrifice polymer (2) on the ITO substrate (tin doped indium oxide) (3) ;

ii) deposition of drops of the solution of conductive polymeric mixtures of PT3MA and PBS previously produced on the substrate of ITO (tin doped indium oxide) with PHS, and centrifugation with air flow (5) in rotation from 1500 to 12000 rpm;

iii) the substrates are then placed on a heated plate (6) between 110 ° C and 130 ° C, preferably 120 ° C, for at least 4 minutes, and the membranes (7) are formed by evaporation of the solvent;

iv) Subsequently, the substrates are immersed in an ethanol solution and the resulting ultrafine membranes (8) finally detached through vibrations produced in the solvent.

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The present invention also describes a process for preparing a conductive polymer mixture of Poly (methyl 3-thiophene acetate) / Poly (vinylidene fluoride) (PT3MA and PVDF) comprising the following steps:

i) dissolution of PVDF in pellets in DMF under a water bath until complete dissolution, forming a solution of variable concentration between 5 and 250 mg / mL.

ii) in another container, PT3MA (Poly (3-thiophene methyl acetate)) doped with anhydrous FeCh is dissolved in DMF (dimethylformamide) and drops of ethyl alcohol PA and heated in a water bath at about 40 ° C and 50 ° C until complete dissolution.

iii) the solutions obtained in i) and ii) are mixed, obtaining a polymeric starting solution whose concentration can vary between 5 and 149 mg / mL;

iv) the solution obtained in step iii) is poured into a container together with Zn ₂ SiO4 in an amount varying between 40 and 240 mg doped with Mn and kept under agitation and heating at about temperature between 40 “C and 60 ° C for a variable period between 12 and 18 hours. This stirring time is necessary for complete solution homogenization to occur.

Still, it is an object of the present invention the process of preparing an electroluminescent device comprises the following steps: 1) partial removal of the ITO through a corrosion process with Zn powder and HCI 1: 1; 2) cleaning with solvents (acetone, water and isopropyl alcohol using ultrasound); 3) deposition of the composite by spinner or drop casting; 4) evaporation of the solvent in an oven and vacuum drying; 5) of aluminum position using evaporator and masks.

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BRIEF DESCRIPTION OF THE FIGURES

The structure and operation of the present invention, together with additional advantages of the same, can be better understood by reference to the attached drawings and the following descriptions:

Figure 1 illustrates the stages of the production process for ultrafine membranes,

Figure 2 shows the synthesis route for the reaction to obtain PT3MA, in which (A) represents polymer solutions and (B) represents films per spinner.

Figure 3 shows the synthesis route for the reaction to obtain the PBS.

Figure 4 illustrates: a) ITO on glass covered with photoresist, b) Polymerization of the resist by exposure to UV light by printing an “appropriate mask pattern to protect regions during the partial ITO removal process.

Figure 5 illustrates: a) image of the photoluminescent device; and b) connection scheme: cathode (Al) (1), active layer (2), anode (ITO) (3), glass (4), light emission (5).

Figure 6 shows the FTIR-ATR spectrum of the monomer, polymers and polymer mixture.

Figure 7 shows the PBS 1H NMR spectrum

Figure 8 (a) shows concentrations used to obtain the calibration curve for PT3MA in a) UV-vis of the polymers and their mixtures.

Figure 8 (b) shows concentrations used to obtain the calibration curve for PT3MA in b) UV-ws of the polymers and their mixtures.

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Figure 9 shows the calibration curve used to develop the Beer Law equation for ο PT3MA.

Figure 10 illustrates UV-v / s absorption spectra of diluted and concentrated solutions of PT3MA in chloroform.

Figure 11 shows a UV-v / s spectrum for diluted solutions (0.01 mg / ml) of PT3MA in chloroform, chlorobenzene and cyclohexanone.

Figure 12 shows UV-v / s for concentrated PT3MA solutions (5 mg / ml) in chloroform, chlorobenzene and cyclohexane.

Figure 13 shows a UV-v / s absorption spectrum of PT3MA from bread 10 with PSSA (À _ma x = 254 nm).

Figure 14 shows the UV-v / s spectrum for ultra-thin PT3MA membranes on ITO substrate obtained by spinning polymer solutions ranging from 0.01 to 5.00 mg / ml. The values of À _max are shown in the figure for each concentration.

Figure 15 shows the calibration curve and graphical calculation of the coefficient dn / dc = 0.144,

Figure 16 shows: a) PBS fusion and bubble formation, b) PBS spherulite formation.

Figure 17 illustrates SEM micrographs of the polymer mixture 20 PT3MA: PBS 50:50 (a), PT3MA (b), and PBS (c).

Figure 18 shows the ultra-thin membrane obtained by dissolving the sacrifice polymer.

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Figure 19 shows AFM images of PT3MA a) highlighted brittle region and b) low porosity. c) 2D image for a 50:50 ultra-thin PT3MA / PBS membrane prepared by a 3000 rpm spinner in 60s.

Figure 20 presents SEM images of a) a 50:50 ultra thin PBS / PT3MA membrane and b) cross section of the polymeric mixture showing the different layers of analysis.

Figure 21 illustrates heating thermograms (20 ° C / min). Curves obtained by DSC analysis showing the behavior of the melting peaks for different PT3MA / PBS samples.

Figure 22 illustrates cooling thermograms (10 ° C / min). Curves obtained by DSC analysis for different PT3MA / PBS samples showing the peaks of endothermic crystallization.

Figure 23 shows heating thermograms (20 ° C / min) showing: ab) glass transition temperatures of the polymers and their mixtures and c) Tg, Tm and DHm (J / g-1) of the PT3MA / PBS 50:50 mixture.

Figure 24 shows TGA thermograms of PBS and their polymer mixtures.

Figure 25 shows SEM micrographs of a 50:50 PT3MA / PBS nanomembrane after (a) one week and (b) four weeks after exposure to enzymatic degradation conditions.

Figure 26 shows SEM micrographs of Hep-2 cells cultured for seven days on the surface of ultrafine membranes of (a) PT3MA / PBS 50:50 and (b) PT3MA.

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DETAILED DESCRIPTION OF THE INVENTION

Although the present invention may be susceptible to different modalities, preferred modalities are shown in the drawings and in the following detailed discussion with the understanding that the present description should be considered an example of the principles of the invention and is not intended to limit the present invention to what has been illustrated and described here.

The main approach of this invention is related to a process for the preparation of conductive polymeric mixtures comprising Poly (methyl 3-thiophene acetate) and Poly (butylene succinate) (PT3MA and PBS), to biodegradable conductive ultrafine membranes produced from said polymeric mixtures . In addition, the present invention relates to a poly (methylthiophene methyl acetate) / poly (vinylidene fluoride) / manganese doped zinc silicate (PT3MA / PVDF / ZnSiC> 4: Mn) composite and films applicable to devices electroluminescents produced from said composites.

Preparation of conductive polymeric mixtures of PT3MA and PBS

In a preferred embodiment of the present invention, the process for preparing conductive polymeric mixtures of poly (methyl 3-thiophene acetate) and poly (butylene succinate) (PT3MA and PBS) comprises dissolving poly (methyl 3-thiophene acetate) and poly (butylene succinate), in the mass ratio in which the amount of PT3MA can vary between 80 and 50, for the amount of PBS variable between 20 and 50, with the preferred mass ratio between them being equal to 80:20, in anhydrous chloroform containing quantity of ethanol varying between 0.5 and 1%,

15/50 resulting in a solution with a variable concentration between 4% and 145 mg / mL, with the preferred concentration being about 5 mg / mL.

Process of preparing a biodegradable conductive membrane from a conductive polymeric mixture of PT3MA and PBS

The steps corresponding to the preparation of the ultrafine biodegradable conductive membrane are illustrated in Figure 1.

In a preferred embodiment of the present invention, the process of preparing a biodegradable conductive membrane comprises the following steps:

i) preparation of polymer to be applied as an intermediate sacrifice layer on which the conductive polymeric mixture produced will be deposited. The sacrifice polymer used was poly (4-hydro-styrene) (PHS). The preparation of the intermediate sacrifice layer comprises the following steps:

1.1) preparation of a solution contains between 4 and 6% by weight of Poly (4hydro-styrene) (PHS), by dissolving the PHS in ethanol;

1.2) deposition of drops of the PHS solution prepared on the surface of an ITO substrate (tin doped indium oxide);

1.3) spreading of the deposited solution at a variable speed between 2500 and 3500 rpm, being preferably equal to 3000 rpm, for a variable period between 30 seconds and 1.5 minutes, being, preferably, time equal to 1 minute. The complete evaporation of the solvent was carried out keeping the sample in a hood under exhaustion.

16/50 ii) deposition of drops of the solution of conductive polymeric mixtures of PT3MA and PBS previously produced on the ITO substrate with PHS, and centrifugation in rotation from 1500 to 12000 rpm, for a variable period between 30 seconds and 1 minute and 30 seconds , being, preferably, time equal to 1 minute;

iii) the substrates are then placed on a heated plate between 110 ° C and 130 ° C, preferably 120 ° C for a period varying between 4 and 6 minutes, with preferential time equal to 5 minutes, and then immersed in a solution of ethanol for dissolving the sacrifice polymer;

iv) after a variable period between 8 and 12 minutes, being preferably equal to 10 minutes, immersion with the aid of an instrument such as tweezers and / or spatula, small vibrations are carried out in the set and the resulting ultrafine membranes are finally detached.

Figure 1 shows in detail the equipment used to obtain the ultrafine membranes by spinner.

The steps corresponding to the synthesis of the Poly (3-thiophene-methyl acetate) are shown in Figure 2. About 30.0 g of the monomer 3-thiophene acetic acid (T3AA) were dissolved in 150 ml of methanol containing a drop of acid sulfuric and kept under reflux at 90 ° C for a period of 24 hours. After completion of the reaction, methanol was evaporated and the obtained ester was washed with diethyl ether and water successively. The brown liquid residue was subsequently dried with anhydrous magnesium sulfate, filtered and identified as 3-thiophene-methyl acetate (T3MA) with 82% reaction yield.

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The Τ3ΜΑ monomer was then polymerized by chemical oxidative coupling. In a three-necked flask, 16.00 g of anhydrous ferric chloride were dissolved in 100 ml of chloroform in an inert environment (nitrogen). With the aid of an addition funnel, 4.0 g (25.64 mmol) of T3MA dissolved in 60 ml of chloroform were added slowly to the reaction flask and kept under stirring at 0 ° C for a period of 24 hours. The dark blue residue was kept at rest in 1L of methanol for precipitation of the polymer and this was washed successively with ethanol and water to remove excess ferric chloride. The light brown precipitate identified as PT3MA by FTIR-ATR was subsequently dried and kept in a dissector with silica. The reaction yield was 80%.

For the synthesis of poly (butylene succinate), as illustrated in Figure 3, about 50g of succinic anhydride and 50g of 1,4-butenediol were added to a three-necked flask connected to a vacuum and nitrogen system and kept under agitation and heating in a silicone oil bath until the temperature reaches 190 ° C. After this step, 1 g of the titanium tetrabutoxide catalyst was added to the flask and the temperature of the reaction medium was raised to 210 ° C, maintaining the reaction for another 3 hours. To eliminate excess 1,4-butanediol the reaction was extended for another 20 hours under the same conditions already mentioned. The final product (white solid) was slowly dispersed in chloroform and the polymer obtained was washed by vacuum filtration. The final product obtained with 90% yield was identified as PBS by ¹ H NMR.

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As will be noted in the examples below, The obtaining and chemical, morphological, electrical characterization of conductive and biodegradable polymeric mixtures formed by the PBS and PT3MA polymers, obtained by chemical synthesis, were evaluated. The confirmation of the synthesis of the polymers was carried out by the techniques of FT1R, ¹ H NMR and UV-v / s. The UV-vis technique proved to be a powerful work tool in the study of the arrangements of the polymer chains and the electrical properties of the conducting polymer. Through the UV-v / s analyzes it was possible to identify the bands and the maximum absorption peaks of PT3MA and from these to estimate the Eg. For diluted solutions, no effect on the π-π * transition absorption of thiophene is verified depending on the chemical nature of the solvent used. For concentrated solutions, a red shift is observed, producing a reduction in Eg. Quantum mechanical calculations in the gas phase indicate that the anti-gauche conformation is more stable than the ali-trans by 3 Kcal / mol per repetitive unit. The values calculated for the two conformations in comparison with the experimental results show that for diluted PT3MA solutions, Eg is closer to the ancientuche conformation than to the ali-anti. For concentrated solutions the reverse is observed. The values of Eg determined for the ultrafine films are relatively smaller than those estimated for the ideal planar molecule. Greater effective packaging of the chains was obtained for films prepared with the most diluted solutions. The nanomembrane preparation technique using PHS sacrifice polymer proved to be efficient for obtaining ultrafine membranes from the PT3MA / PBS polymeric mixture. As shown earlier, the

19/50 technique of deposition of ultrafine membranes by spinnert played an important role in the preparation of polymeric mixtures. The MO images allowed to evaluate the domains and the distribution of the polymers in the ultrafine membranes, as well as the SEM / FIB micrographs to estimate the thickness of the polymer membranes and mixtures.

The AFM images made it possible to evaluate the roughness of PT3MA and, together with the SEM micrographs and the thermal analyzes DSC and TGA of the films obtained by casting, to choose the composition PBS / PT3MA 20:80 as the best relation to obtain a material with good mechanical property, that is, with good flexibility (characteristic of the PBS polyester component), and at the same time with good conductive properties (characteristic of the conductive PT3MA polyethylene component). The electrical conductivity measurements using a two-point technique show that the ultra thin PBS / PT3MA 20:80 membrane presents values from -10 ^-4 to -10 ' ⁵ S / cm, values compatible with those of semiconductor polythiophenes with lateral carboxylic acid group mentioned in literature. The degradation, growth and cell proliferation tests on the ultrafine membranes made up of mixtures of the two polymers indicate that PBS is the main responsible for mechanical integrity and that the new PT3MA / PBS membrane is a potential candidate for application as bioactive platforms with semiconductor responses for tissue engineering. However, studies on the maximum percentage of PT3MA in the composition of the ultrafine membrane have yet to be carried out due to the low bioactivity of the polymer due to the toxicity of the T3MA monomer.

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Preparation of a polymeric conductive mixture of PT3MA and PVDF

In a preferred embodiment of the present invention, the process for preparing a conductive polymer mixture of Poly (methyl 3-thiophene acetate) / Poly (vinylidene fluoride) (PT3MA and PVDF) comprises the following steps:

i) dissolving PVDF in pellets in DMF under a water bath at about 90 ° C until complete dissolution, forming a solution of about 5 g / ml.

ii) in another container, PT3MA (Poly (3-thiophene methyl acetate)) doped with anhydrous FeCI ₃ is dissolved in DMF (dimethylformamide) and drops of ethyl alcohol PA and heated in a water bath at about 40 ° C until complete dissolution .

iii) the solutions obtained in i) and ii) are mixed, obtaining a polymeric starting solution with a concentration that can vary between 5 and 149 mg / mL;

iv) the solution obtained in step iii) is poured into a container with Zn ₂ SiO4 in an amount varying between 40 and 240 mg doped with Mn and kept under agitation and heating at a temperature between 40 ° C and 60 ° C, with preferential temperature equal to 50 ° C, for a period between 12 and 18 hours. This stirring time is necessary for complete solution homogenization to occur.

The preferred final ratio of PVDF: PT3MA / inorganic material used for mounting the device is 80: 20/80.

In an alternative embodiment of the present invention, the process of preparing more concentrated polymer solutions of PVDF / PT3MA, maintaining the 80:20 ratio, comprises the following steps:

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i) about 250 mg of PVDF were completely diluted in 1 ml of dimethylformamide, at a temperature of about 60 ° C, with stirring over a 24 hour period;

ii) concomitantly, in two other containers, 40 mg of PT3MA are diluted in 0.5 ml of DMF and 8 mg of FeCI ₃ in 0.5 ml of DMF, respectively, adopting the same conditions of time, temperature and agitation used in the dilution of PVDF.

iii) the solutions of the containers containing PT3MA and FeClg are mixed and stirred for a period of 8 hours for the doping of the polymer to occur;

iv) the solution obtained in step iii) and the solution containing PVDF are mixed and stirred for about 24 hours.

v) the solution obtained in step iv) is poured into a container together with 240 mg of Zn ₂ SiO ₄ doped with Mn and kept under stirring and heating at about 50 ^D C for a period of approximately 12 hours

The increase in concentration makes the mixture more viscous and ideal for obtaining thicker active layers, as it forms a colloid with the inorganic material. The formation of the colloid prevents the particles of inorganic material from precipitating in advance during the evaporation step of the solvent in an oven, guaranteeing the adherence of the active layer to the ITO substrate.

The composite deposition tests for obtaining thick films were performed on the ITO substrate at rest. The samples were placed in an oven with air recirculation and the solvent evaporated at

22/50 room temperature. Subsequently, these were kept in a vacuum and kept in a dissector with silica.

In a preferred embodiment of the present invention, the process of preparing a polymeric conductive mixture of PT3MA and PVDF is conducted under ambient atmospheric pressure (not modified by vacuum, for example). During the experimental phase, when the atmospheric pressure was reduced, the film detached itself from the ITO due to the rapid evaporation of the DMF solvent.

The steps corresponding to the synthesis of the Poly (3-thiophene-methyl acetate) are shown in Figure 2. About 30.0 g of the monomer 3-thiophene acetic acid (T3AA) were dissolved in 150 ml of methanol containing a drop of acid sulfuric and kept under reflux at 90 ° C for a period of 24 hours. After completion of the reaction, methanol was evaporated and the obtained ester was washed with diethyl ether and water successively. The brown liquid residue was subsequently dried with anhydrous magnesium sulfate, filtered and identified as 3-thiophene-methyl acetate (T3MA) with 82% reaction yield.

The T3MA monomer was then polymerized by chemical oxidative coupling. In a three-necked flask, 16.00 g of anhydrous ferric chloride were dissolved in 100 ml of chloroform in an inert environment (nitrogen). With the aid of an addition funnel, 4.0 g (25.64 mmol) of T3MA dissolved in 60 ml of chloroform were added slowly to the reaction flask and kept under stirring at 0 ° C for a period of 24 hours. The dark blue residue was kept at rest in 1L of methanol for precipitation of the polymer and this was washed successively with ethanol and water to remove excess ferric chloride.

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The light brown precipitate identified as PT3MA by FTIR-ATR was subsequently dried and kept in a dissector with silica. The reaction yield was 80%.

As will be shown by the examples presented below, the method of polymerization by photochemical reaction allows the synthesis of polyanion polyanion PT3AA-K and poly (3-thiophene methyl acetate) and the preparation of their polymeric mixtures with the poly (vinylidene fluoride) polymer increasing the electrical conductivity of the fluoropolymer used as a matrix. The technique of photochemical synthesis in aqueous solution, innovative in the preparation of conductive polymeric mixtures consisting of poly (3-alkylthiophenes) / Polyfluorates, offers as an option the use of a tool for rapid synthesis and with the generation of less waste when compared to traditional techniques chemical and electrochemical synthesis. The amount of conductive polymer incorporated will depend on the reaction time, the porosity of the matrix membrane and the dosages of UV radiation used during the reaction. The structural characterization techniques FTIR and ¹ H NMR confirmed the syntheses of the polymers, respectively, by the presence of characteristic absorptions attributed to their functional groups and by the absence of displacements corresponding to the a protons of the aromatic ring. Analysis of UV-vis in solution of PT3MA samples shows a maximum absorption band at 407 nm as already observed for the chemically synthesized polymer. The SEM images show that polymerization on the matrix surface is non-uniform and that it tends to start from the surface into the host membrane. Pores with sizes of 2

24/50 to 4 in diameter present in the membrane direct the growth of the conductive polymer chains and limit the amount of material incorporated.

Thermogravimetric analyzes indicate an increase in the melting temperature of the polymeric mixtures due to the presence of the reaction product in their pores that can act as energy barriers to the fusion of the crystalline phases of the PVDF. The electrical conductivity measurements of semiconductor polymeric mixtures indicate a significant increase in conductivity of pure PVDF for the polymeric mixture containing 26% PT3AA-K from 10 ¹⁵ to 6 x 10 ^'11 S / cm and show that the membranes do not tend to undergo variations conductivity when doped with TSA.

In a preferred embodiment of the present invention, the process of preparing a conductive membrane PT3MA / PVDF or PT3AA-k / PVDF conducted by the photochemical polymerization of the T3MA or T3AA-K monomer comprises the following steps:

The esterification reaction of the monomer 3-thiophene acetic acid (T3AA) was carried out according to the procedures suggested by Sugimoto ¹⁸ and Osada ¹⁹ as (Scheme 1). About 30.0 g of T3AA monomer were dissolved in 150 ml of methanol containing a drop of sulfuric acid and kept under heating at reflux at 90 ° C for a period of 24 hours. After completion of the reaction, methanol was evaporated and the obtained ester was washed with diethyl ether and water successively. The brown viscous residual liquid was subsequently dried with anhydrous magnesium sulfate, filtered and identified as 3-thiophene-methyl acetate (T3MA) with 82% reaction yield. The steps corresponding to

25/50 esterification of the monomer 3-thiophene-methyl acetate (T3MA) are found in the

Layout 1

T3AA T3MA

Scheme 1. Procedure used for T3MA synthesis. The photochemical synthesis reactions were carried out in a closed environment, at a temperature of 50 ° C, in a steady state using UV radiation emitted by a 400 W mercury lamp at intervals of 5 to 40 minutes. A typical example of photochemical synthesis adopted for the monomer 3-thiophene acetic acid (T3AA) during the tests can be described as follows: 10 ml of aqueous solution of the monomer 3-thiophene acetic acid (0.2 mol L ¹ ) were mixed with 10 ml of potassium dichromate solution (0.6 mol L ' ¹ ) in small circular Pyrex discs. After complete homogenization, a sample of polymeric matrix of poly (vinylidene fluoride) (PVDF) previously weighed was immersed in the monomeric solution and kept at rest, in the absence of light, for a period of 10 minutes, sufficient time for the matrix to reach complete wetting. After the reaction by exposure to light, the product not incorporated into the matrix and the polymer mixture formed Polyanion Poli (thiophene acetic acid) / Poly (vinylidene fluoride) (PT3AA-K and PVDF) are washed separately several times with water to remove the contaminating chromium, subsequently dried in an oven at 90 ° C for 24 hours and stored in

26/50 desiccator for a period of 3 days. The polymeric mixture, after drying, is weighed and the percentage of product incorporated into the matrix determined by gravimetric analysis using Equation 1:

% PP = (mass of the polymeric mixture - mass of the PVDF matrix) (1) (mass of the polymeric mixture)

% PP represents the percentage of product incorporated into the matrix.

Similar procedures were adopted for photochemical polymerization of the T3MA monomer and formation of the poly (methyl 3-thiophene acetate) / poly (vinylidene fluoride) membrane (PT3MA and PVDF). In this case, the monomeric solutions used in the syntheses were prepared by mixing water-ethanol solvents in a 1: 1 ratio.

Preparation process of electroluminescent devices

In a preferred embodiment of the present invention, the process of preparing electroluminescent devices from conductive polymeric mixtures of Poly (methyl 3-thiophene acetate) / Poly (vinylidene fluoride) (PT3MA and PVDF) is preceded by a cleaning process and partial removal of the ITO, to ensure the removal of possible contaminants that could affect the performance of the device, comprising the following steps:

a) an ITO plate is partially covered with adhesive tape and its exposed region protected with enamel;

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b) after removing the tape, the plate is placed in a container with HCI 1: 1 solution and powdered Zn and kept between 12 and 18 minutes in ultrasound, with a preferential period equal to 15 minutes;

c) ITO on the unprotected region is removed by an oxireduction reaction;

d) the plate is then taken for a cleaning process in three stages: acetone (for removing the enamel), isopropyl alcohol variable between 70 ° C and 90 ° C in Millipore water, for a variable period between 12 and 18 minutes in ultrasound, preferential period equal to 15 minutes;

The partial removal of the ITO from the glass plate has as main objectives to avoid possible short-circuit caused by direct contact between the electrodes of the device, either by migration of the Aluminum layer through the active layer or by perforations caused by external contacts (alligator mouth and tips) suffered during the characterization of the electrical properties of the device.

An optical lithography process using photoresites was used to attempt to engrave a protective mask pattern during partial removal of the ITO. The photo lithography allows to demilitate regions of functioning of the active layer of the device and thus reproduce drawings with the light emitted by the device. The process begins with the deposition of a photo-resistive layer by spinner (speed of 3000 rpm) on the entire ITO surface (1). This layer, also called photoresist (2), consists of a monomeric organic liquid. Then a pre-cure of photoresist 1518 is performed in a

28/50 hot plate “hot plate” at a temperature of 120 ^and C for 2 minutes. A mask pattern (photolith) (3) is aligned with the substrate (ITO) in a photoaligner with an ultraviolet light source (Figure 4) that performs the photoresist polymerization by passing light (4) through the transparent region of the photolith. contains the pattern to be transferred to the substrate. The photoresist region protected by the opaque part of the photolith is not polymerized and can be removed using a developing solvent, in this case, MIF-300.

The regions protected with unpolymerized photoresist do not suffer chemical attack during the surface treatment and can replace the method of protection using with enamel as previously described.

Thus, in a preferred embodiment of the present invention, the process for preparing an electroluminescent device comprises the following steps: 1) partial removal of the ITO through a corrosion process with Zn powder and HC11: 1; 2) cleaning with solvents (acetone, water and isopropyl alcohol using ultrasound); 3) deposition of the composite by spinner or drop casting; 4) evaporation of the solvent in an oven and vacuum drying; 5) of aluminum position using evaporator and masks.

EXAMPLES

Example 1 - Infrared spectroscopy with Fourier transform

Through the analysis of FTIR spectra (Figure 6) it was possible to characterize and identify the ester and its respective polymer obtained by the synthetic route suggested in Figure 1. The absence of the intense and wide band corresponding to the hydroxyl group for acids confirms the esterification of the T3AA monomer in their respective ester

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Τ3ΜΑ. The presence of an absorbance at 3090 cm ' ¹ can be attributed to the CH stretch at the position of the thiophene ring. This absorbance is present in the spectrum of the T3MA ester monomer and absent in the spectrum of the PT3MA polymer indicating that the T3MA polymerization reaction actually occurred.

The presence of low intensity peaks at 764 cm-1 and 710 cm ¹ corresponding to CH deformation out of the plane for the T3MA monomer and their absence in the PT3MA polymer spectrum are also indicators that the polymerization reaction has been successful.

In the same figure 6, for the PBS sample it was possible to assign some bands: group C = O in 1714 cm ¹ , CO stretching at 1150 cm * ¹ and OH deformation at 950 cm * ¹ .

The other bands identified and assigned to the PT3MA sample were: group C = O at 1726 cm ' ¹ and asymmetric CH deformation of the methyl ester group at 1429 cm- ¹ . Analyzes of membranes made up of 1: 1 PT3MA / PBS polymer mixtures were also performed. In this case, bands were observed at 1713 cm * ¹ and at 1150 cm * ¹ impossible to be attributed to the polymers since they have similar groups that absorb in the same region. The bands corresponding to the PBS C = O and CO groups seem to stand out over the PT3MA bands.

Table 1 shows a comparison of the absorptions observed in the FTIR spectra for PT3MA and PBS polymers and for their mixtures in the following proportions PBS / PT3MA 50:50, PBS / PT3MA 80:20 and PBS / PT3MA 20:80. The PT3MA spectrum, mentioned earlier, shows a peak

30/50 small and narrow at 3000 cm ' ¹ attributed to vibrations CH stretch corresponding to the hydrogen of the thiophene ring. This band is not present in the mixtures, probably due to its overlap by the bands, more intense and wider, corresponding to the aliphatic CH (-CH ₂ -) stretching vibrations of the PBS that occur in the same region (between 3050 and 2850 cm ' ¹ ). Stretch vibrations of groups C = O for esters were observed in all spectra in the region between 1730 and 1710 cm ' ¹ , The absorbance attributed to the ring stretch vibration at 1429 cm' ¹ for the PT3MA spectrum was also observed only in the spectrum of blends PBS / PT3MA 20:80. In this same region for the PBS spectra and the PBS / PT3MA 50:50 and PBS / PT3MA 80:20 blends spectra, an absorption close to 1470 cm ' ¹ was observed corresponding to the vibration of the aliphatic CH stretch of the methylene groups of the polyester.

Absorption bands between 1460 and 1400 cm ' ¹ in the PBS spectrum and their blends were observed and attributed to the CO stretch (versus CH deformation) of the PBS chain-ending carboxylic acid. These bands should be followed by other absorption bands between 1320 and 1210 cm ' ¹ , however they remain superimposed by the presence of the absorptions corresponding to CO stretching vibrations of the polyester and polyethylene ester groups (between 1260 and 1150 v). The peaks observed in all spectra close to 1340 cm ' ¹ were attributed to CH deformation of the PBS methylene groups and the P3TMA methyl groups. The presence of a peak close to 950 cm ¹ was detected in the spectra of PBS and its mixtures and attributed to OH deformation of the carboxylic acid group. Absorptions corresponding to CH deformations, characteristics of

31/50 chains containing 4 methylene groups or more linked in their structure, were observed close to 750 cm ' ¹ and attributed to the methylene groups of the polyester. Peaks corresponding to aromatic CH deformations for polytrophenes were observed, respectively, close to 835 and 735 cm-1 for spectra 5 of P3TMA and its blends PBS / PT3MA 50:50 and PBS / PT3MA 20:80 (Table 1).

Table 1. Comparison of absorptions (cm ^-1 ) in the infrared of membranes prepared from polymers and their mixtures by drop casting in chloroform solvent.

X _________ u- Compound Aríini. v (C-llj α β Alil ‘. viC Iii ÉsLcr □, Ring • ÍCCl Alif. ·. IC 16 KsLcr C Hi Acid. ·. <Οΐ 41 -Hl Acid. Mclilcno cClhí * <? Ll lll.iis viC-Hi Year. XClh α β ΡΤ3ΜΛ 1258. KMH 501X1 2951 1726 1429 1341 1 1'34, 1 150 PEiS 1OÍF » - ? mI5. 2X55 17) 4 1472. 1318 1) 50 1,137 and 1400 954 747 - - 1Ί HMVPÜS 1.1 - 2943. 2S57 17 (3 - 1469. 1.33f) 1153 1458 and 1405 953 744 - 835 PRS / PT3MA X: 2 - 2945. 28.57 1711 - 1469, 1,319 115: 1 1458 and 1405 952 7IX - - PRS / ΡΤΛΜΑ 2.X - 2948. 2849 1720 1428 1321 1257. 1151 - 956 73? 7.17 áf>

Example 2 - ¹ H NMR Nuclear Magnetic Resonance spectra

The structure of the Poly (butylene succinate) (Formula 1) was determined by ¹ H NMR (Figure 7). The chemical shifts obtained by the spectra were correlated with the polymer structure and with the literature.

_T ϊ fl_

--OCHjCHjCHjCHjOCCHjCHjC-32/50

Formula I

The shifts observed in the 'H NMR spectrum (Table 2) were: d 7.25 ppm (CDCh), d 4.15 ppm (2H, t, methylene -CH ₂ O (C = O) -R), d 2 , 45 ppm (2H, t, methylene -CH ₂ - (CO) -R), d 1.75 ppm (2H, q, methylene R-CH ₂ -R) (Table 2).

Table 2 - Chemical displacements (ppm) of PBS

PBS Chemical Displacement (ppm) Chloroform 8 7.25 ρρπΗΠΧ’Β) -CZZ ₂ O (C = OhR Õ 4.15 ppm UILtjnetiJeno) -CZZ _r (C = Oi- ò 2.45 ppm <211. t. methylene i R-CZZj-R 1.75 ppm Ull.q.metilenot

Example 3 - Visible Ultraviolet Absorption Spectroscopy

The UV-ws analyzes of PT3MA samples in chloroform solutions (Figure 8 (a)) were used to aid their characterization by analyzing specific absorptions in their spectra. After optimizing the samples, it was possible to select polymer concentrations to build a calibration curve for the polymer. The diluted solutions show a maximum absorbance peak for ο PT3MA at 400 nm in chloroform. This absorption in this region is characteristic of the p-p * transitions of the thiophene ring for most poly (3-alkylthiophenes). By analyzing the UV-ws spectra of the blends, it was possible to observe 15 only this band with lower absorption intensity with the gradual increase in the mass of PBS in the mixture (Figure 8 (b)).

Two explanations are given for this behavior: the absence of chromophore groups in the PBS that absorb this wavelength (250-550

33/50 nm) and the absence of intermolecular interaction between PBS and PT3MA as shown by the phase separation (formation of distinct sites containing only one of the polymers) detected in the photos of optical microscopy. The little miscibility between the PT3MA and PBS polymers indicated by the thermograms of their mixtures (presence of two distinct and distant Tg) and absence of new absorptions or displacements of those already existing with the gradual increase of PBS in their composition show an absence of interaction between the groups functional properties of polymers.

The UV-v / s absorbance data at 400 nm was used to construct the calibration curve. For each concentration, 3 measurements were taken. With the average maximum absorbance values obtained at each concentration of solution, it was possible to draw the calibration curve (Figure 8 (aJ), absorbance versus PT3MA concentration in chloroform (mol / L) and obtain the molar absorptivity value of the polymer (and ) through the slope of the graph line. The equation used to draw the curve follows Beer’s law, expressed in the equation below.

A (Àniiix = 4 (Χ) ητη) = F-b-c where A is measured absorbance, b is the path taken by the sample and c (mol / L) is the concentration of the sample.

The expression A = 6193.7c + 0.1038 and the value of e corresponding to 6193.7 mol g ^ cm ' ¹ were obtained from the calibration curve (Figure 9). The numerical value added to the equation at 0.1038 was attributed to systematic experimental errors from the cuvette, air, solvent and others.

Example 4 - Effect of concentrated solutions (0.03 mg / ml to 2.5 mg / ml)

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The chemical reaction between the polymer and the dopant could be observed by changes in the UV-vis spectrum. Figure 7 compares the UV-vvs spectra of PT3MA in chloroform varying the concentrations from 0.03 mg / ml to 2.5 mg / ml. A comparative analysis between the _{M X} of the spectra of Figure 8 , and 10 was performed. The π-π * transition of the thiophene ring shows a red shift with respect to the analyzes performed for more diluted solutions indicating that the π conjugation length increases with the polymer concentration, that is, the energy required for the π-π * transition decreases.

The same maximum wavelength of 400 nm for diluted solutions is increased to 496 nm for the most concentrated solution. The second band observed in the spectra of the concentrated solutions can be attributed to the formation of polaron and bipolaron species in the polymer chains, showing the influence of the doping agent.

Example 5 - Effects of solvents

A study of the influence on the energy gap (Eg) of the polymer by alternating the use of solvents (chloroform, chlorobenzene and cyclohexanone) and variations in their concentrations was carried out. In diluted solutions (0.01 mg / ml), little effect on the π-π * absorption band is observed when chloroform solvent is changed to more polar and less volatile solvents (Figure 11).

Wavelengths with maximum absorption at 400.407 and 400 nm were observed, respectively, for the solutions of concentration 0.01 mg / ml of PT3MA in chloroform, chlorobenzene and cyclohexanone. The gap bands calculated by the onset wavelength À _onS et of the UV-ws spectrum result in values,

35/50, respectively, of 2.56, 2.48 and 2.48 eV. The small difference in values between the gap bands (less than 0.1 eV) suggests that the solvent has little influence on the displacement of electron n. Thus, although the dielectric constant of the solvents varies from 3.7 (chloroform) to 15.6 (cyclohexanone), the nature of the non-specific solute-solvent interactions is similar in all cases, minimizing the effects (hydrogen bonds between PT3MA and solvents are not possible).

On the contrary, in concentrated solutions (5 mg / ml) the solvent has an important role in its electronic structures. In these cases, the solvent affects the position of the π-π * transition peak. Those obtained for transition π-π * from chloroform, cyclohexanone and chlorobenzene were 508, 522, 537 nm, respectively. The absorption spectra in UVv / s for concentrated solutions show the occurrence of a red shift when the solvent volatility decreases which results in a reduction in the energy required for the π-π * transition (Figure 12).

The value of Eg calculated for chloroform (vapor pressure of 160mmHga 20 ° C) is 2.09 eV, while the values for the solvents cyclohexanone (pressure vapor 3.4 mmHg at 20 ° C) and chlorobenzene (vapor of pressure 11.8 mmHg at 25 ° C) decrease, respectively, to 1.91 and 1.89 eV. The results show that the intramolecular interactions between the molecules of the polymers are affected by the mobility of the solvents which in turn vary with their volatilities . Another important characteristic of these curves is that the

36/50 oxidation at 744 nm is only observed in the chloroform solution (0.050,100% ethanol) confirming that this band corresponds to the FeCh complex. Example 6 - Effect produced by the addition of other dopants

Drops of poly (styrene sulfonic acid) PSSA and dodecyl benzene sulfonic acid DBSA were added to diluted (0.001, 0.005 and 0.001 mg / ml) and concentrated (5.0 mg / ml) solutions of PT3MA in chloroform to assess its doping effects. The amount of dopant used in the solutions was equivalent to 10% of the mass of the polymer used in the preparation of these. The spectra of Uv-v / s of PT3MA doped with PSSA and DBSA were similar to those obtained with ferric chloride from polymerization. For example, the values of À _{r [iax} and Eg obtained for PSSA in chloroform solution (0.01 mg / ml) were 403 nm and 2.53 eV, respectively (Figure 12). The values obtained for DBSA were 403 nm and 2.54 eV. These values are very close to those obtained for ο PT3MA from polymerization (À _max = 400 and Eg = 2.56).

Both PSSA and DBSA show poor doping behavior for ο PT3MA. This behavior is consistent with that found in the literature attributed to the short distance between the conjugated chain and the side chain carboxylate group.

Example 7 - Ultra-thin PT3MA membranes

Figure 14 shows the absorption spectra of PT3MA ultrafine membranes. The thickness values of the polymeric films were varied using different concentrations of polymer solution from 0.01 to 5 mg / ml. Although the absorption profiles recorded in solid state are similar to those

37/50 obtained in solution, the thickness of the films affects the absorption peaks and absorbance. The maximum wavelengths of the films obtained using solutions 0.01, 1.00 and 5 mg / ml in chloroform were 482, 433 and 419 nm, respectively. These results show a blue shift with increasing PT3MA concentration in solution. The gap energies increase with the concentration, from 1.52 to 2.17 eV when the concentrations are varied from 0.01 to 5.00 mg / ml. These results indicate that a better and more effective packaging of conjugated structure π is obtained when more diluted solutions are used in the preparation of the films, in addition, the low Eg energy determined for the ultra thin membranes produced by diluted solutions indicates that the intermolecular effects of lengths of conjugation p are more important in solid state as they were recently predicted by ab-initio calculations.

Truly, Eg for nanofilms obtained from a 0.01 mg / ml solution is 0.37 eV less than that predicted for an isolated polymeric chain in an ideal planar conformation.

It is also important to note that the Eg measured for the ultrafine membrane obtained by spinner using a 5.00 mg / ml solution (2.17 eV) is greater than that determined by the UV-v / s analysis of a solution of the same concentration, regardless of the solvent (1.89-2.09 eV). Thus, for ultrafine membranes, the reduction in the gap energy produced by the π stacking interactions between the aromatic rings is not sufficient to compensate for the negative conformational effects on the molecular length of the tt conjugation. Therefore, the use of spinner for concentrated solutions produces distortions in the

38/50 shape of the polymer chains, which are not able to readapt their conformations due to the packaging of the surrounding molecules.

Example 8 - Study of the influence of molecular conformation on the electronic properties of PT3MA

The all-anti conformation, situation in which all dihedral angles between rings (Θ defined by the sequence S-C-C-S) adopt the value of 180 ° C, was used as the initial structure in all cases for Quantum Mechanics Calculations.

The Density Functional Theory (DFT) was used for the geometric optimization of the polymer according to the preference of the conformation of the methyl 10 acetate group. For this purpose, Quantum Mechanics Calculations on 4T3MA were performed using the gas phase, a condition in which the polymer is free of any type of interaction with the solvent. The two less energy, almost isoenergetic, arrangements are shown below. The arrangement of the methyl acetate groups that differ in their arrangement was designed for an anti-arrangement for all the dihedral angles between rings (q = 180 °).

The arrangements differ by the spatial arrangement of the methyl acetate group. Arrangement I maintains the same orientation for all repetitive units (all

39/50 above the plane), while arrangement II differs by alternating the dispositions (above and below the plane). However, the energy difference between the two is very small, the first structure being more stable at 0.1 Kcal / mol. The dihedral angles between the rings of these two structures take on an anti-gauche shape with the angle varying from 130 to 132 °.

The quantum mechanical calculations performed for ο Π-Τ3ΜΑ varying the repetitive monomer units (n) from 2 to 10 for arrangements I and II (both ancientuche) show that the destabilization energy value found is 0.3 Kcal / mol. This small difference suggests that the interaction between the polymer's main chain and its methyl acetate substituent group is very small.

The same calculations were performed for an all-anti conformation considering the same arrangement of the lateral substituting groups attributed to the first arrangement (fixing the dihedral angles between rings at 180 ° C). The all-anti conformation is less stable than the anti-gauche, since the relative energy tends to increase from 1.9 to 12.8 Kcal / mol when it does not vary from 2 to 10.

Table 4 shows a summary with the values of λ max, λ onset and Eg determined experimentally and theoretically for ο PT3MA in different solutions. The values of Eg predicted for an infinite chain of PT3MA for the first array, the second array and all-anti are 2.78, 2.93 and 1.89 eV. These results show the influence of the conformation of the polymer main chain on the PI and EA used to estimate Eg.

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As expected, Eg decreases when the planarity of the main chain increases, a behavior that can be attributed to the improvement of the conjugation produced when the dihedral angles between rings go towards a value close to 180 ° C. The Eg values obtained for the first and second 5 arrangements are overestimated, respectively, by 0.22 and 0.37 eV to the calculated value for the diluted chloroform solution (backing solvent) of Eg = 2.56 eV. In contrast, the Eg value of the all-anti conformation is underestimated by 0.67 eV. Therefore, in diluted chloroform solution, the main chain of the polymer molecules must be in an intermediate conformation between the anti-gauche and all10 anti, although it is closer to the first.

In contrast, Eg foreseen for concentrated chloroform solutions (5mg / ml) is closer to the alhantido conformation than to the anti-gauche conformation. The difference is 0.2 and 0.69 eV, respectively. The explanation for this behavior is that, in concentrated solutions, the chains of PT3MA 15 tend to acquire planar arrangements that are totally consistent with the red shift observed previously for À _ma x, that is, the conjugation length increases in chains of polymer.

Table 4 - Values of Àm _ax , λο _η5θ ι and E _g for ο PT3MA.

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Ó11Í1A Λ'ίΗΙΜί.'Ι E _b icV) Soi. diluted chloroform (0.01 mg / ml) 40Õ 485 2.56 Diluted sol. Of doivtenzcno (0.01 tng ^ inl) 407 500 2.48 Diluted cyclohexanone sol (0.01 mg / mli 400 4ÕÕ 2.48 Sol. Chloroform concentrate (5.00 mg / ml) 508 592 2.00 Sol. Dorobcnzcnu concentrate (5.00 nig / mb 537 657 1.89 Sol. Concentrated cyclohexannna (5.00 mg / ml) 522 647 1.92 DIT calculations. 1’asc gasosti. arrangement 1 - - 2.78 Calculation ^ DFT, gas phase, arrangement 11 - - 2.93 Calculation ·· DIT. gas laser. tilt-ani - - 1.89 Xtnorihncs-spinncT · (0.01 nig / inli 482 £ 14 1.52 Xanofilms-spinner <1.00 mg / ml i 433 626 1.98 Nanolilincs-spimicr <5.00 tng / tnl) 419 572 2.17

In addition, this flatness increases when the volatility of the solvent decreases, the Eg predicted for the concentrated chlorobenzene solution is identical to that calculated for an ideal all-anti conformation.

Example 9 - Gel Permeation Chromatography (GPC)

A calibration curve was constructed in order to determine the dn / dc coefficient (Figure 13) and the absolute molar mass of the polymer. For this purpose solutions of PT3MA polymer in chloroform solvent were prepared. From a 5 mg / ml solution (stock solution), solutions with 10 more diluted concentrations of the polymer were obtained using 10 ml flasks and using the Ci x Vf = Cf x Vf ratio, where the ief indexes represent the concentrations and initial and final volumes of the preparation. Three species with different molar masses were observed in the analysis with retention volumes of 14.6; 14.8 and 19.1 ml. The first species with the second largest fraction (44.7%)

42/50 corresponding to 400-401 mere showed an average molar mass (Mz) of 7.0 x 104 Da, the second species with a greater fraction of 47.9% (380-381 mere) with Mz of 6.8 x 104 Da and the third species (fraction of 7.4% and 21-22 mere) with an average molar mass of 3.3 x 103 Da.

Example 10 - Optical Microscopy

The distribution of PBS polymers and spherulites in membranes can be observed by analyzing images obtained by optical microscopy of PBS / PT3MA 50:50 films deposited on ITO plates. With the aid of a heating plate and the addition of a color filter, it was also possible to assess the crystallinity of the polymers that make up the studied membranes. Figure 16 (a) shows the formation of small bubbles resulting from the fusion of PBS at 109 C during heating the film to 200 ° C. After cooling the film to 70 ° C (Figure 16 (b)) it was possible to observe the formation of small spherulites resulting from the recrystallization of the PBS.

The analysis of the films in the presence of a color filter revealed the formation of three distinct sites: a brown amorphous polymeric region attributed to PT3MA, a second whitish-green region consisting of PBS spherulites and a third gray region corresponding to a empty site only with the ITO substrate.

Example 11 - Scanning Electron Microscopy (SEM)

SEM micrographs show that the distribution of PT3MA over PBS is completely homogeneous on the PBS / PT3MA 50:50 membrane. The spherical phases shown in the micrographs were attributed to PT3MA due to

43/50 sulfur concentrations detected by dispersive energy spectroscopic analyzes (EDS) Figures 17 (a).

The SEM micrographs of PT3MA shown in Figure 17 (b) show the formation of spherical nanoaggregates of small and medium sizes. The membranes formed by PT3MA do not have good mechanical properties, as they break easily when handling them. In addition, large particles can be observed detaching from their surface after some time of their formation. However, mechanical integrity is achieved by mixing with PBS. The PBS membranes show lamellar aggregates with a certain degree of porosity (Figure 17 (c)). The porosity presented and expected by these microstructures allows a better effective mixture between the polyester and the conductive polymer.

Increasing the content of PBS in the PT3MA: PBS membrane significantly increases its flexibility. This characteristic property of Polifbutilene succinato) is even more pronounced when its chains are not so long. Gain in mechanical properties for polymeric PBS / Polystyrene mixtures have already been observed by the introduction of polyester.

Example 12 - Digital images of ultrafine membranes

Ultra thin membranes of the polymeric mixture PBS / PT3MA in the proportions 50:50, 80:20 and 20:80 can be obtained using the spinner technique on glass substrates covered with an ITO nanometer layer or on silicon disk using a polymeric intermediate layer of poly (4-hydroxy-styrene)

PHS.

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The photos obtained with the camera of a bench optical microscope (Figure 18) show the moment when the film detaches from the ITO plate after the complete dissolution of the PHS polymer in ethanol.

Example 13 - Atomic Force Microscopy (AFM)

AFM images (Figure 19 a-b) show the surface topography of two different sites on the same PT3MA membrane deposited on ITO substrate by spinner (8000 rpm, 60s) from 5mg / ml polymeric solution. Figure 19c shows the image of a 50:50 PT3MA / PBS membrane.

The average roughness determined for the two analyzed regions (Figure 19 (a) and (b)) were, respectively, 14 and 8 nm. The images also detected greater protuberances and rupture points in the first region analyzed (Figure 19 (a)). This remarkable difference can be attributed to the low mechanical properties of pure polythiophene, such as hardness and rigidity, making its films quite brittle. It was also possible to observe in the images the low porosity existing in the films obtained. The thickness of the PT3MA membranes with PBS (polymeric mixture PT3MA / PBS 50:50) was determined by AFM (Figure 19 (c)). A calibration curve (thickness x rotation) with films of different thicknesses was created using a spinner. The tests were performed varying the equipment's rotation from 1500 to 12000 rpm for periods of 60 s.

According to the curve, the thickness of a membrane obtained by rotating 8000 rpm for 60 s can be between 20 and 30 nm.

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Figure 20 (a) shows the SEM image of the surface and cross section of an ultra thin PBS / PT3MA 50:50 membrane deposited by spinner at 8000 rpm on ITO substrate. Thickness measurements by FIB for the obtained film were performed obtaining values close to 50 nm Figure 20 (b).

The interferences found during the measurements and the proximity of the thickness values between substrate and the analyzed film made it impossible to accurately determine the thickness of the polymeric films by FIB although the results were sufficient to estimate an approximate value.

Example 14 - Thermal Analysis: Differential Scanning Calorimetry (DSC) 10 and Thermogravimetric Analysis (TGA)

Table 5 summarizes the thermal properties of the polymers and their mixtures obtained by analyzing the DSC and TGA thermograms. DSC heating thermograms show that the melting of the crystalline fraction of PBS is affected by the presence of polythiophene. PBS and its mixtures have two 15 melting peaks Tm at 102 and 112.8 ° C.

These peaks can be clearly seen in the pure PBS thermograms (Figure 21).

This behavior can be associated with two factors. In the first case, the most likely, the presence of the two peaks may be related to the existence of two populations of lamenar crystals with different thicknesses (the peak at 102 ° C would correspond to the fusion of the finer crystals that when undergoing reorganization would produce intermediate exothermic peak). In the second case,

46/50 more specifically to mixtures, due to spherical nanoaggregates of

PT3MA dispersed between the crystalline phases of PBS.

Table 5 - Properties polymeric thermal of polymers and their mixtures Polinur »i: m Mhnira T * (('/ T _r rCi PBS - 34 93.2 102. 1 12.8 75.0 390 ΡΤ3ΜΛ 49.7 - - - -314 PT3MA / PRS 2Π; ΧΟ -27.7 and 62.3 73.5 112.5 73.8 385 ΡΊ3ΜΑ / ΡΒ8 50:50 - 25 and 72 68. 8 111.8 66.5 357 PT3MA / PRS 80:20 - 10.3 and 37.7 62.0 1 1 1.6 33.4 320 ^the iranescence of widowhood. ^b Icmpcraiuru dc iTÍsUilkuçau. ^v lempcnuura of Portuguese. ^d

melting enthalpy ^and decomposition temperature

In Figure 21, the presence of a single exothermic peak close to 112 ° C in the thermograms of the mixtures suggests an increase of 10 ° C in Tm over the 102 ° C exothermic peak for pure PBS.

The spherical PT3MA nano-aggregates present in the composition of the mixture could be acting as true barriers, requiring more energy to melt the PBS crystals. Similar cases of Tm increase for polymeric mixtures with PT3MA are mentioned in the literature. The domain density number of spherical polythiophene nanoaggregates decreases considerably with an increase in the percentage of PBS in the membrane composition and again two peaks can be observed equally to those 15 obtained observed for PBS.

According to the values in Table 5 and the analysis of the DSC cooling thermograms for different PT3MA / PBS samples (Figure 22) it is

47/50 it is possible to state that the PBS Tc crystallization temperature is hampered by the presence of PT3MA. The Tc exothermic crystallization peaks and the crystallization enthalpies decrease when the PT3MA content increases. The Tc values range from 93.2 to 62.0 ° C of the pure PBS for the mixture with 80% PT3MA.

The DSC heating thermograms of the PBS, PT3MA polymers and their mixtures with the respective glass transition temperatures Tg are shown in Figures 23 a-c. The two Tg values observed in the thermograms of the polymeric mixtures indicate partial miscibility between the studied polymers.

The heating curves obtained by the conventional fusion method followed by rapid quenching of the polymeric mixtures (Figures 23 a-b) show two glass transition temperatures. This expected behavior of glass transition temperatures is in accordance with the phase separation seen under microscopy. Its values vary according to the composition of the mixture as follows: the glass transition temperature associated with PT3MA decreases with an increase in its content in the mixture while the Tg associated with PBS increases when the concentration of polyester decreases.

The thermograms of the thermogravimetric analyzes (Figure 24) of the polymers and their mixtures show an increase in the degradation temperature and residual mass with an increase in the PBS content in the mixtures. This behavior can be attributed to the higher decomposition temperature of the PBS (Td = 389 ° C) in relation to that determined for ο PT3MA (Tc / -314 ° C). The increase in PBS content provides greater stability to the polymer mixture.

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Example 15 - Electrical conductivity measurements

The electrical properties of the ultra-thin PT3MA / PBS 80:20 membranes were evaluated on an insulating substrate using a Keithley 6430 Sourcemeter. The conductivity values determined for the ultra-thin membrane varied from -10 ^ to ~ 10 ⁵ S / cm depending on its thickness . These values are within the range typically found for semiconductor polythiophenes with carboxylic acid groups on the side chain. However, it was not possible to measure the conductivity of the ultrafine membranes constituted by the other polymer mixing ratios.

Example 16 - Enzymatic degradation tests

The degradation studies of the PT3MA / PBS mixture carried out with Lipase OS (procedure used to verify the efficiency of the degradation of aliphatic polyester films) show that the process starts after one week as observed in the SEM micrographs by the appearance of fine grooves on the surface (Figure 25 (a)). After an additional 2 weeks, the grooves turn into real large and deep cracks causing the PT3MA domains to detach and solubilization in the middle of low molar mass products due to the action of Lipase on the PBS (Figure 25 (b)). The ultra-thin membranes made up only of PT3MA do not suffer any type of degradation even after 4 weeks of study. These undergo a swelling process due to the polar nature of the carboxylate group. These results show that polyester is not only essential for the mechanical integrity of the membrane, but also for its biodegradability.

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Example 17 - Cell adhesion and proliferation assays

A comparative quantitative analysis between ultra-thin membranes of PT3MA, PBS, 50:50 polymeric mixtures as substrate for cell adhesion and proliferation was performed using HEp-2 human epithelial cell lines, Polystyrene under TCPS tissue culture was used in the assays as a control substrate . The results show that cell adhesion on ο PT3MA is less than that verified on TCPS control substrate, while adhesion on PT3MA / PBS 50:50 polymeric mixture and on PBS is similar to that verified for TCPS.

After 7 days of culture under identical conditions, an analysis of cell activity on the surface of ultrafine membranes of the PT3MA / PBS 50:50 and pure PT3MA mixture was performed. Analyzing the SEM micrographs, it is possible to observe the formation of a monocellular layer with wide spread (indicated by arrows) for the membranes constituted by the mixture PT3MA / PBS 50:50 Figure 25 (a) while for ο PT3MA a large number of domains without cells (represented by asterisks) Figure 25 (b).

The use of polyester as a biomaterial in biomedical applications is widely accepted for its biodegradability. The combination of PBS with PT3MA allowed to improve the use of polyester as a bioactive platform. Polythiophene has a recognized compatibility, but its monomers are toxic. Cell adhesion on polythiophenes has been reported in the literature and favored by the following two considerations: its morphology is adequate to establish

50/50 contact between cells and anion exchange between the conductive polymer and the cell across the cell membrane.

Thus, although only some modalities of the present invention have been shown, it will be understood that various omissions, substitutions and changes can be made by a technician versed in the subject, without departing from the spirit and scope of the present invention. The described modalities should be considered in all aspects only as illustrative and not restrictive.

It is expressly provided that all combinations of elements that perform the same function in substantially the same way to achieve the same results are within the scope of the invention. Substitutions for elements from one modality described to another are also fully intended and contemplated.

It is also necessary to understand that the drawings are not necessarily to scale, but that they are only of a conceptual nature. The intention is therefore to be limited, as indicated by the scope of the appended claims.

Claims (15)

1. Process of preparation of conductive polymeric mixture characterized by the fact that it comprises the dissolution of poly (methyl 3-thiophene acetate), in a variable proportion between 80 and 50 and poly (butylene succinate) in variable proportion 5 between 20 and 50, in anhydrous chloroform, resulting in a solution with a variable concentration between 4 and 6 mg / mL. 2. Process of preparation of conductive polymeric mixture characterized by the fact that it comprises the dissolution of poly (methyl 3-thiophene acetate) and poly (butylene succinate) in preferential mass ratio equal to 80:20, in 10 anhydrous chloroform containing between 0.5% and 1.0% ethanol, resulting in a solution with preferential concentration equal to 5 mg / mL. 3. Process of preparing a conductive biodegradable membrane characterized by the fact that it comprises the following steps: i) Preparation of an intermediate sacrifice layer by centrifugation 15 (1), with poly (4 ~ hydro-styrene) (PHS) being used as a sacrifice polymer (2) on the ITO substrate (tin doped indium oxide) (3); ii) deposition of drops of the solution of conductive polymeric mixtures of PT3MA and PBS previously produced on the substrate of ITO (tin doped indium oxide) with PHS, and centrifugation with air flow (5) in rotation of 20 1500 to 12000 rpm; iii) then the substrates are placed on heated plate (6) between 110 ^Q C and 130 ° C for a period varying between 4 and 6 minutes and the membranes (7) formed by evaporation of the solvent; 2/4 iv) Subsequently, the substrates are immersed in an ethanol solution and the resulting ultrafine membranes (8) finally detached. Process according to claim 2, characterized by step (iii) using preferential temperature equal to 120 ^and C and time preferably equal to 5 minutes. 5. Process according to claim 1, characterized by the fact that said preparation of an intermediate sacrifice layer from step i) comprises the steps of: 1.1) preparation of a 5% solution by weight of Poly (4-hydro-styrene) (PHS) by dissolving the PHS in ethanol; 1.2) deposition of drops of the PHS solution prepared on the surface of an ITO substrate (tin doped indium oxide); 1.3) spreading of the deposited solution at a variable speed between 2500 and 3500 rpm for a variable period between 30 seconds and 1.5 minutes. 6. Process according to claim 5, characterized by the solution described in step (i.1) having a concentration preferably equal to 5%. Process according to claim 5, characterized in that the solution described in step (i.3) is spread at a speed preferably equal to 3000 rpm, for a period preferably equal to 1 minute. 8. Process for preparing a conductive polymeric mixture characterized by the fact that it comprises the following steps: i) dissolving PVDF in pellets in DMF under a water bath at about 90 ° C until complete dissolution, forming a solution of about 5 g / ml. 3/4 ii) in another container, PT3MA (Poly (3-thiophene methyl acetate)) doped with anhydrous FeCÍ3 is dissolved in DMF (dimethylformamide) and drops of ethyl alcohol PA and heated in a water bath at about 40 ° C until complete dissolution. iii) the solutions obtained in i) and ii) are mixed, obtaining a starting polymer solution with a variable concentration between 5 and 149 mg / mL; iv) the solution obtained in step iii) is poured into a container with Zn ₂ SiO ₄ in an amount varying between 40 and 240 mg, doped with Mn and kept under agitation and heating at a temperature between 40 ° C and 60'C for a variable period between 12 and 18 hours. Process according to claim 8, characterized by the starting solution obtained in step (iii), preferably having a concentration equal to 5 mg / mL. 10. Process according to claim 8, characterized by step (iv) using a preferential amount of Zn ₂ SiO ₄ equal to 40 mg, preferably heated for 12 hours at a temperature equal to 50 ° C. 11. Process, according to claim 8, characterized by the fact that the final PVDF: PT3MA / inorganic material used for assembly of the device is 80: 20/80. 12. Process according to claim 8, characterized by the fact that it is conducted at room temperature. 13. Process of preparing an electroluminescent device characterized by the fact that it comprises the following steps: 1) partial removal of ITO through a corrosion process with Zn powder and HCI 1: 1; 2) 4/4 cleaning with solvents (acetone, water and isopropyl alcohol using ultrasound); 3) deposition of the conductive polymer mixture as defined in claims 4 to 6; 4) evaporation of the solvent in an oven and vacuum drying; 5) of aluminum position using evaporator and masks. 5 14. Process, according to claim 13, characterized by the fact that the deposition of step 3) is conducted by spinner. 15. Process, according to claim 13, characterized by the fact that the deposition of step 3) is conducted by drop casting.