Luminita Wagner - Academia.edu (original) (raw)
Papers by Luminita Wagner
Journal of Coatings Technology and Research, 2020
In this paper, we report the synthesis of different silica materials via the acid-catalyzed sol–g... more In this paper, we report the synthesis of different silica materials via the acid-catalyzed sol–gel process at room temperature (25°C), using silane precursors with various alkyl chains (dimethyl, octyl and/or hexadecyl), in order to obtain thin films with anti-reflective and hydrophobic properties. Chemical, optical and structural properties of obtained silica materials were thoroughly characterized with various techniques such as FTIR and UV–Vis spectroscopy, AFM analysis, ellipsometric measurements, ESEM and TEM microscopy. Wettability of thin films was evaluated by water contact angle measurements. FTIR spectra of silica materials revealed that the intensity of the Si–O–Si characteristic bands varies depending on the precursor type. From AFM results, we found that the obtained films present a different microstructure as a function of the silica sol formulations. The hydrophobic character of the thin films increases with increasing the length of the hydrophobic chains following the order: dimethyl < octyl < hexadecyl. UV–Vis analysis of the coatings covered with silica materials presents a low reflectance (15.5%). The proposed method in this work has the potential to be a low-cost processing path of nanostructured anti-reflection transparent substrates.
ALINA RADITOIU1, VALENTIN RADITOIU1*, VIORICA AMARIUTEI1, CRISTIAN ANDI NICOLAE1, AUGUSTA-RALUCA ... more ALINA RADITOIU1, VALENTIN RADITOIU1*, VIORICA AMARIUTEI1, CRISTIAN ANDI NICOLAE1, AUGUSTA-RALUCA GABOR1, ADRIANA-NICOLETA FRONE1, RADU CLAUDIU FIERASCU1, MARIUS GHIUREA1, LUMINITA EUGENIA WAGNER1, GHEORGHE HUBCA2 1 National Research and Development Institute for Chemistry and Petrochemistry – ICECHIM, 202 Splaiul Independentei, 060021, Bucharest, Romania 2 University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science, 149 Calea Victoriei, 010072, Bucharest, Romania
Coatings obtained on cellulose fabrics with nonionic dyes – silica hybrids have been investigated... more Coatings obtained on cellulose fabrics with nonionic dyes – silica hybrids have been investigated. Composition of the impregnation bath and parameters having a major influence on coloring properties were studied in relationship with washing and light fastness. It was found that cotton can be coated with organic-inorganic nonionic dyes silica hybrids exhibiting fair washing and light fastness. Properties of the coated materials can be controlled by variation of parameters affecting sol obtaining procedures or impregnation conditions. The presence of only one trialkoxysilane group per chromogen makes the formation of a highly crosslinked silica network to be difficult. The partial condensation of DR1-PTES (Disperse Red 1 dye covalently linked to 3-isocyanatopropyltriethoxysilane) to the stage of oligomeric structures, together with the existence of silanol and unhydrolyzed alkoxysilane groups can explain leaching behavior of the coatings obtained with this type of hybrid materials.
The paper presents disperse azo dyes-silica hybrids deposited as coating materials on the surface... more The paper presents disperse azo dyes-silica hybrids deposited as coating materials on the surface of cellulose fibres by sol-gel processes. Coatings are characterised by FT-IR spectrometry, UV-VIS reflectance spectra and colour measurements in CIELAB system, scanning electron microscopy (SEM) and thermal analysis (TA). Structure-properties relationships of the obtained coatings are discussed with respect to the structure of azo dyes embedded in the silica networks. The effect of functional groups grafted on the structure of disperse dyes was studied in relationship with leaching properties of the obtained coloured coatings.
The paper presents experimental data regarding some azobenzenes synthesized by coupling diazonium... more The paper presents experimental data regarding some azobenzenes synthesized by coupling diazonium salt of 2,6-dichlor-4-nitro-, 2-cyan-4-nitroor 4-nitro-aniline with different coupling components as: N-βacetoxyethyl-N-β-cyanoethyl-, N-ethyl-N-β-hydroxyethyl-, N,N-di-β-hydroxyethyl-3-methyl-aniline and selective reduction of nitrodyes with obtaining the corresponding azodyes having primary amino groups grafted on the azostructure. Reaction products were purified and characterized by means of elemental analysis, UV-VIS, IR and 1H-NMRspectroscopy. Structure-property relationships in the azoderivatives are discussed with respect to the structure and nature of the substituents.
The article presents experimental data regarding synthesis and characterization of some xanthene ... more The article presents experimental data regarding synthesis and characterization of some xanthene derivatives. Reaction products were purified and characterized by means of elemental analysis, UV-Vis absorption, fluorescence emission, IR absorption, 1H-NMR and 13C-NMR spectroscopy. There were obtained compounds with hydrophobic properties especially for their usage as markers for petroleum products.
Proceedings, 2020
Due to their range of applications, from anti-icing to self-cleaning, low-adhesion, antibacterial... more Due to their range of applications, from anti-icing to self-cleaning, low-adhesion, antibacterial. [...]
Coatings, 2020
Fluorescent film-forming materials were obtained by embedding salicylaldazine (SAA) in silica hyb... more Fluorescent film-forming materials were obtained by embedding salicylaldazine (SAA) in silica hybrids generated by sol–gel processes from different silane precursors in acid catalysis. Tuned local environments for the fluorophore were generated in the hosting network by modifying silica sols with organic groups through the co-condensation of tetraethylortosilicate (TEOS) and different alkoxysilanes hydrolysis products. The photophysical properties of the luminescent hybrid films were studied in direct relationship with structural, textural, and surface properties and based on interactions between SAA species and the silica hosting network. Film-forming materials were studied in order to determine differences in absorption and fluorescence emission due to the environments around the fluorophore. The variations recorded in the fluorescence emission spectra of the hybrid films were related to interactions established between the fluorophore species and their sterically hindered surroun...
Materiale Plastice, 2018
The seven curcumin derivatives were deposited on palygorskite in order to obtain hybrid materials... more The seven curcumin derivatives were deposited on palygorskite in order to obtain hybrid materials. The fluorescence emission spectra of the obtained materials show a decrease in fluorescence intensity relative to the respective dyes, due to the environments around the dyestuff molecules created in the host matrices. Absorption studies show the best adsorption on the inorganic matrix, for the compounds with the hydroxyl groups. Correlating fluorescence spectra of hybrid materials with the results for absorption spectra of the dyes adsorbtion on the surface of the clay lead to the conclusion that a high percentage of the adsorbed dye had the effect of fluorescence quenching. Thus, it was confirmed that the fluorescent properties of hybrid materials depend on the interactions established between the fluorescent dyestuff and the inorganic network.
Materiale Plastice, 2019
The photochemical degradation of polyolefin-TiO2 composite films was investigated and described i... more The photochemical degradation of polyolefin-TiO2 composite films was investigated and described in relationship with the concentration of photocatalyst and after different exposure times. UV-Vis-NIR and IR spectra reveal the presence of various degradation products, which are in direct connection with the photodecomposition mechanism. Various ratios between the absorbance of some typical IR characteristic bands can lead to the evaluation of photocomposition of polyethylene and polypropylene composite films containing TiO2 nanoparticles.The results show that the photocatalytic degradation of composites is significantly faster than the simple photolytic decomposition of pure polypropylene and polyethylene and could be used as a solution for the destruction of this type of wastes.
Revista de Chimie, 2018
Seven curcumin derivatives were synthesized by an ecological method, in a microwave field. The co... more Seven curcumin derivatives were synthesized by an ecological method, in a microwave field. The compounds obtained were purified and characterized by means of elemental analysis, UV-VIS, fluorescence, IR, 1H-NMR and 13C-NMR spectroscopy. Structure-property relationship in the b-diketone derivatives are discussed with respect to the structure and nature of the substituents for possible applications in optical sensors and luminescent materials.
Proceedings, 2019
Transparent hydrophobic or super-hydrophobic thin films prepared on plastic substrates haveattrac... more Transparent hydrophobic or super-hydrophobic thin films prepared on plastic substrates haveattracted attention in recent years because they can be suited to optical applications such as lenses [...]
Dyes and Pigments, 2016
Several binary composites based on Crystal Violet Lactone (CVL) color former and Phenolphthalein ... more Several binary composites based on Crystal Violet Lactone (CVL) color former and Phenolphthalein (PPht) developing agent dissolved in 1-tetradecanol (TD) were studied in order to determine how different ratios between components influence the thermochromic behavior of the composites. The color dependence on temperature was investigated in direct relationship with structural changes and interactions between components. The stoichiometry of the colored complex was determined from diffuse reflectance data and confirmed by means of steady state fluorescence measurements and temperature modulated differential scanning calorimetry. The color former: developing agent molar ratio equal to 1:2.5 was determined to ensure the reversibility of the process in optimal conditions. The characteristics of the color path and the influence of thermal history during thermochromic transition were analyzed from the variations of CIELAB color parameters during successive heating/cooling cycles. Dynamic colorimetric properties of the thermochromic binary composite containing the components in optimum ratio are described by four characteristic temperatures in the hysteresis.
Revista de Chimie -Bucharest- Original Edition-
ABSTRACT
Revista de Chimie -Bucharest- Original Edition-
The paper presents some triarylmethane dyes and their use in thermochromic systems of donor-accep... more The paper presents some triarylmethane dyes and their use in thermochromic systems of donor-accepting type. Compounds are characterized by FT-IR spectra, UV-Vis reflectance spectra and color measurements in CIELAB system and thermal analysis. Some considerations are made in relationship with dyestuff structure, developing agent and solvents used to obtain thermochromic systems. The effect of the ratio between the developing agent and lactone dye on the color differences was studied from reflectance spectra and colour measurements while the influence of the solvent type on the transition temperature was analyzed using dynamic scanning calorimetry.
Revista de Chimie -Bucharest- Original Edition-
The paper presents experimental data regarding coloration of protein fibers using film building s... more The paper presents experimental data regarding coloration of protein fibers using film building silica hybrids containing disperse dyes embedded or covalently linked into the inorganic network. Properties of the coatings are studied from the point of view of colour strength, fastness to light and washing and thermal stability in relation to their composition. The proposed method allows obtaining coloured protein fibers in a single step, with good uniformity and intensity using disperse dyes, which in dyeing practice are not intended to colour this type of fibers.
![Research paper thumbnail of Photophysical properties of some fluorescent materials containing 3-methoxy-7H-benzo[de]anthracen-7-one embedded in sol–gel silica hybrids](https://attachments.academia-assets.com/87180557/thumbnails/1.jpg)
](Optical Materials, 2015
Several fluorescent materials were prepared by embedding 3-methoxy-7H-benzo[de]anthracen-7-one in... more Several fluorescent materials were prepared by embedding 3-methoxy-7H-benzo[de]anthracen-7-one in transparent sol-gel silica hybrids, in acid catalysis and at room temperature. The photophysical properties of the materials are studied in relationship with the structure and based on interactions established between the fluorophore, which display high sensitivity to minor changes in the local environments, and hybrid silica networks. Colored materials show marked differences in absorption and fluorescence spectra due to the environments around the dyestuff molecules created in the host matrices by grafting different organic moieties onto silica surface. The fluorescence emission spectrum of the obtained materials reveals a positive solvatochromism due to the intramolecular charge transfer character of the excited states and changes in the fluorophore dipole moment. Variations recorded in the fluorescence parameters of the hybrid materials confirm that some interactions are established between the fluorescent dyestuff and hybrid silica network.
Journal of Optoelectronics and Advanced Materials
The paper presents new types of coloured organic-inorganic hybrids deposited as coating materials... more The paper presents new types of coloured organic-inorganic hybrids deposited as coating materials on the surface of cellulose materials by sol-gel processes. Coated materials were characterized by: XRF spectrometry, FT-IR spectrometry,UV-VIS reflectance spectra and colour measurements in CIELAB system, scanning electron microscopy (SEM), thermal analysis (TA) and dynamic mechanical analysis (DMA). Structure-properties relationships of the obtained coated cellulose materials are discussed with respect to the structure and nature of the hybrid organic-inorganic coloured coatings.
A derivative of p-aminoazobenzene-epoxy resin was studied. Visually examination between crossed p... more A derivative of p-aminoazobenzene-epoxy resin was studied. Visually examination between crossed polarizers does not show birefringence but it can be optically induced. Changing the polarization direction of the irradiating light leads to the changing of the privileged direction of the induced birefringence. The birefringence value was evaluated and compared with liquid crystals as anisotropic compounds.
Journal of Optoelectronics and Advanced Materials
Present study refers to the analysis of the matrix polarity effect on polymer dispersions contain... more Present study refers to the analysis of the matrix polarity effect on polymer dispersions containing crystal violet lactone thermochromic complex. Thus, the synthesis by miniemulsion polymerization of blue colored latexes based on different monomer types using polyvinyl alcohol as colloid, was followed. The obtained coloured latexes were characterized and their thermochromic behavior was verified.
Journal of Coatings Technology and Research, 2020
In this paper, we report the synthesis of different silica materials via the acid-catalyzed sol–g... more In this paper, we report the synthesis of different silica materials via the acid-catalyzed sol–gel process at room temperature (25°C), using silane precursors with various alkyl chains (dimethyl, octyl and/or hexadecyl), in order to obtain thin films with anti-reflective and hydrophobic properties. Chemical, optical and structural properties of obtained silica materials were thoroughly characterized with various techniques such as FTIR and UV–Vis spectroscopy, AFM analysis, ellipsometric measurements, ESEM and TEM microscopy. Wettability of thin films was evaluated by water contact angle measurements. FTIR spectra of silica materials revealed that the intensity of the Si–O–Si characteristic bands varies depending on the precursor type. From AFM results, we found that the obtained films present a different microstructure as a function of the silica sol formulations. The hydrophobic character of the thin films increases with increasing the length of the hydrophobic chains following the order: dimethyl < octyl < hexadecyl. UV–Vis analysis of the coatings covered with silica materials presents a low reflectance (15.5%). The proposed method in this work has the potential to be a low-cost processing path of nanostructured anti-reflection transparent substrates.
ALINA RADITOIU1, VALENTIN RADITOIU1*, VIORICA AMARIUTEI1, CRISTIAN ANDI NICOLAE1, AUGUSTA-RALUCA ... more ALINA RADITOIU1, VALENTIN RADITOIU1*, VIORICA AMARIUTEI1, CRISTIAN ANDI NICOLAE1, AUGUSTA-RALUCA GABOR1, ADRIANA-NICOLETA FRONE1, RADU CLAUDIU FIERASCU1, MARIUS GHIUREA1, LUMINITA EUGENIA WAGNER1, GHEORGHE HUBCA2 1 National Research and Development Institute for Chemistry and Petrochemistry – ICECHIM, 202 Splaiul Independentei, 060021, Bucharest, Romania 2 University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science, 149 Calea Victoriei, 010072, Bucharest, Romania
Coatings obtained on cellulose fabrics with nonionic dyes – silica hybrids have been investigated... more Coatings obtained on cellulose fabrics with nonionic dyes – silica hybrids have been investigated. Composition of the impregnation bath and parameters having a major influence on coloring properties were studied in relationship with washing and light fastness. It was found that cotton can be coated with organic-inorganic nonionic dyes silica hybrids exhibiting fair washing and light fastness. Properties of the coated materials can be controlled by variation of parameters affecting sol obtaining procedures or impregnation conditions. The presence of only one trialkoxysilane group per chromogen makes the formation of a highly crosslinked silica network to be difficult. The partial condensation of DR1-PTES (Disperse Red 1 dye covalently linked to 3-isocyanatopropyltriethoxysilane) to the stage of oligomeric structures, together with the existence of silanol and unhydrolyzed alkoxysilane groups can explain leaching behavior of the coatings obtained with this type of hybrid materials.
The paper presents disperse azo dyes-silica hybrids deposited as coating materials on the surface... more The paper presents disperse azo dyes-silica hybrids deposited as coating materials on the surface of cellulose fibres by sol-gel processes. Coatings are characterised by FT-IR spectrometry, UV-VIS reflectance spectra and colour measurements in CIELAB system, scanning electron microscopy (SEM) and thermal analysis (TA). Structure-properties relationships of the obtained coatings are discussed with respect to the structure of azo dyes embedded in the silica networks. The effect of functional groups grafted on the structure of disperse dyes was studied in relationship with leaching properties of the obtained coloured coatings.
The paper presents experimental data regarding some azobenzenes synthesized by coupling diazonium... more The paper presents experimental data regarding some azobenzenes synthesized by coupling diazonium salt of 2,6-dichlor-4-nitro-, 2-cyan-4-nitroor 4-nitro-aniline with different coupling components as: N-βacetoxyethyl-N-β-cyanoethyl-, N-ethyl-N-β-hydroxyethyl-, N,N-di-β-hydroxyethyl-3-methyl-aniline and selective reduction of nitrodyes with obtaining the corresponding azodyes having primary amino groups grafted on the azostructure. Reaction products were purified and characterized by means of elemental analysis, UV-VIS, IR and 1H-NMRspectroscopy. Structure-property relationships in the azoderivatives are discussed with respect to the structure and nature of the substituents.
The article presents experimental data regarding synthesis and characterization of some xanthene ... more The article presents experimental data regarding synthesis and characterization of some xanthene derivatives. Reaction products were purified and characterized by means of elemental analysis, UV-Vis absorption, fluorescence emission, IR absorption, 1H-NMR and 13C-NMR spectroscopy. There were obtained compounds with hydrophobic properties especially for their usage as markers for petroleum products.
Proceedings, 2020
Due to their range of applications, from anti-icing to self-cleaning, low-adhesion, antibacterial... more Due to their range of applications, from anti-icing to self-cleaning, low-adhesion, antibacterial. [...]
Coatings, 2020
Fluorescent film-forming materials were obtained by embedding salicylaldazine (SAA) in silica hyb... more Fluorescent film-forming materials were obtained by embedding salicylaldazine (SAA) in silica hybrids generated by sol–gel processes from different silane precursors in acid catalysis. Tuned local environments for the fluorophore were generated in the hosting network by modifying silica sols with organic groups through the co-condensation of tetraethylortosilicate (TEOS) and different alkoxysilanes hydrolysis products. The photophysical properties of the luminescent hybrid films were studied in direct relationship with structural, textural, and surface properties and based on interactions between SAA species and the silica hosting network. Film-forming materials were studied in order to determine differences in absorption and fluorescence emission due to the environments around the fluorophore. The variations recorded in the fluorescence emission spectra of the hybrid films were related to interactions established between the fluorophore species and their sterically hindered surroun...
Materiale Plastice, 2018
The seven curcumin derivatives were deposited on palygorskite in order to obtain hybrid materials... more The seven curcumin derivatives were deposited on palygorskite in order to obtain hybrid materials. The fluorescence emission spectra of the obtained materials show a decrease in fluorescence intensity relative to the respective dyes, due to the environments around the dyestuff molecules created in the host matrices. Absorption studies show the best adsorption on the inorganic matrix, for the compounds with the hydroxyl groups. Correlating fluorescence spectra of hybrid materials with the results for absorption spectra of the dyes adsorbtion on the surface of the clay lead to the conclusion that a high percentage of the adsorbed dye had the effect of fluorescence quenching. Thus, it was confirmed that the fluorescent properties of hybrid materials depend on the interactions established between the fluorescent dyestuff and the inorganic network.
Materiale Plastice, 2019
The photochemical degradation of polyolefin-TiO2 composite films was investigated and described i... more The photochemical degradation of polyolefin-TiO2 composite films was investigated and described in relationship with the concentration of photocatalyst and after different exposure times. UV-Vis-NIR and IR spectra reveal the presence of various degradation products, which are in direct connection with the photodecomposition mechanism. Various ratios between the absorbance of some typical IR characteristic bands can lead to the evaluation of photocomposition of polyethylene and polypropylene composite films containing TiO2 nanoparticles.The results show that the photocatalytic degradation of composites is significantly faster than the simple photolytic decomposition of pure polypropylene and polyethylene and could be used as a solution for the destruction of this type of wastes.
Revista de Chimie, 2018
Seven curcumin derivatives were synthesized by an ecological method, in a microwave field. The co... more Seven curcumin derivatives were synthesized by an ecological method, in a microwave field. The compounds obtained were purified and characterized by means of elemental analysis, UV-VIS, fluorescence, IR, 1H-NMR and 13C-NMR spectroscopy. Structure-property relationship in the b-diketone derivatives are discussed with respect to the structure and nature of the substituents for possible applications in optical sensors and luminescent materials.
Proceedings, 2019
Transparent hydrophobic or super-hydrophobic thin films prepared on plastic substrates haveattrac... more Transparent hydrophobic or super-hydrophobic thin films prepared on plastic substrates haveattracted attention in recent years because they can be suited to optical applications such as lenses [...]
Dyes and Pigments, 2016
Several binary composites based on Crystal Violet Lactone (CVL) color former and Phenolphthalein ... more Several binary composites based on Crystal Violet Lactone (CVL) color former and Phenolphthalein (PPht) developing agent dissolved in 1-tetradecanol (TD) were studied in order to determine how different ratios between components influence the thermochromic behavior of the composites. The color dependence on temperature was investigated in direct relationship with structural changes and interactions between components. The stoichiometry of the colored complex was determined from diffuse reflectance data and confirmed by means of steady state fluorescence measurements and temperature modulated differential scanning calorimetry. The color former: developing agent molar ratio equal to 1:2.5 was determined to ensure the reversibility of the process in optimal conditions. The characteristics of the color path and the influence of thermal history during thermochromic transition were analyzed from the variations of CIELAB color parameters during successive heating/cooling cycles. Dynamic colorimetric properties of the thermochromic binary composite containing the components in optimum ratio are described by four characteristic temperatures in the hysteresis.
Revista de Chimie -Bucharest- Original Edition-
ABSTRACT
Revista de Chimie -Bucharest- Original Edition-
The paper presents some triarylmethane dyes and their use in thermochromic systems of donor-accep... more The paper presents some triarylmethane dyes and their use in thermochromic systems of donor-accepting type. Compounds are characterized by FT-IR spectra, UV-Vis reflectance spectra and color measurements in CIELAB system and thermal analysis. Some considerations are made in relationship with dyestuff structure, developing agent and solvents used to obtain thermochromic systems. The effect of the ratio between the developing agent and lactone dye on the color differences was studied from reflectance spectra and colour measurements while the influence of the solvent type on the transition temperature was analyzed using dynamic scanning calorimetry.
Revista de Chimie -Bucharest- Original Edition-
The paper presents experimental data regarding coloration of protein fibers using film building s... more The paper presents experimental data regarding coloration of protein fibers using film building silica hybrids containing disperse dyes embedded or covalently linked into the inorganic network. Properties of the coatings are studied from the point of view of colour strength, fastness to light and washing and thermal stability in relation to their composition. The proposed method allows obtaining coloured protein fibers in a single step, with good uniformity and intensity using disperse dyes, which in dyeing practice are not intended to colour this type of fibers.
Optical Materials, 2015
Several fluorescent materials were prepared by embedding 3-methoxy-7H-benzo[de]anthracen-7-one in... more Several fluorescent materials were prepared by embedding 3-methoxy-7H-benzo[de]anthracen-7-one in transparent sol-gel silica hybrids, in acid catalysis and at room temperature. The photophysical properties of the materials are studied in relationship with the structure and based on interactions established between the fluorophore, which display high sensitivity to minor changes in the local environments, and hybrid silica networks. Colored materials show marked differences in absorption and fluorescence spectra due to the environments around the dyestuff molecules created in the host matrices by grafting different organic moieties onto silica surface. The fluorescence emission spectrum of the obtained materials reveals a positive solvatochromism due to the intramolecular charge transfer character of the excited states and changes in the fluorophore dipole moment. Variations recorded in the fluorescence parameters of the hybrid materials confirm that some interactions are established between the fluorescent dyestuff and hybrid silica network.
Journal of Optoelectronics and Advanced Materials
The paper presents new types of coloured organic-inorganic hybrids deposited as coating materials... more The paper presents new types of coloured organic-inorganic hybrids deposited as coating materials on the surface of cellulose materials by sol-gel processes. Coated materials were characterized by: XRF spectrometry, FT-IR spectrometry,UV-VIS reflectance spectra and colour measurements in CIELAB system, scanning electron microscopy (SEM), thermal analysis (TA) and dynamic mechanical analysis (DMA). Structure-properties relationships of the obtained coated cellulose materials are discussed with respect to the structure and nature of the hybrid organic-inorganic coloured coatings.
A derivative of p-aminoazobenzene-epoxy resin was studied. Visually examination between crossed p... more A derivative of p-aminoazobenzene-epoxy resin was studied. Visually examination between crossed polarizers does not show birefringence but it can be optically induced. Changing the polarization direction of the irradiating light leads to the changing of the privileged direction of the induced birefringence. The birefringence value was evaluated and compared with liquid crystals as anisotropic compounds.
Journal of Optoelectronics and Advanced Materials
Present study refers to the analysis of the matrix polarity effect on polymer dispersions contain... more Present study refers to the analysis of the matrix polarity effect on polymer dispersions containing crystal violet lactone thermochromic complex. Thus, the synthesis by miniemulsion polymerization of blue colored latexes based on different monomer types using polyvinyl alcohol as colloid, was followed. The obtained coloured latexes were characterized and their thermochromic behavior was verified.