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The solÁgel process can be used to coat a nylon substrate, changing the properties of the material and the interaction between the coating and the substrate takes place through the NH groups of nylonThe application of thin films as coating on several surfaces has been one of the major factors responsible for technological advances. Additive Manufacturing is used to define a set of technologies that have the building of 3D physic prototypes as a common characteristic. In this work we have studied the properties of Polyamide 12 samples obtained by rapid prototyping after coating with different metal transitions by solÁgel methodology. The sols were prepared with silicon, vanadium, titanium, or aluminum alkoxide. Thermal analysis revealed an increase in the decomposition temperature of the materials, which was attributed to the coating. Differences in the morphology of the films were detected by scanning electron microscopy, which depended on sol composition. The Raman spectra confirmed interaction between the coating and nylon substrate. The prepared materials exhibited new properties, such as higher thermal stability, while maintaining its initial characteristics, like low density, thereby promoting new potential applications.

Additive manufacture is an effective technology to produce complex macrostructures from polymers. Sol-gel is a chemical process that affords multifunctional materials by functionalization of different substrates. This work reports on the use of acrylonitrile-butadiene-styrene polymer (ABS) as starting material to obtain a substrate by additive manufacture. Coating of ABS by the sol-gel methodology generated a multifunctional material. Sols with and without phosphate ions were prepared from silicon and calcium alkoxide. Based on X-ray diffraction patterns, a calcium phosphate crystalline structure emerged on ABS after contact of the substrate with simulated body fluid. Infrared analysis revealed that the peaks of the functionalized substrate shifted, indicating that ABS interacted with the sol-gel coating. According to thermal analysis, the maximum decomposition temperature of the coated samples was 20 °C higher as compared to non-coated ABS. Sol-gel and additive manufacture are important technologies to produce materials with applications in biological medium. Keywords: dip-coating, sol-gel, biomaterials IntroductionAdditive manufacture (AM, also known as rapid prototyping) assembles materials in the powder, filament, liquid, or slide form. The materials consist of successively stacked thin layers, resulting in a three-dimensional structure.AM uses computer-aided design (CAD) software to build a mould for the scaffold. The mould displays a branching network of shafts that will define the microchannels in the scaffold.1-5 The fusion deposition model (FDM) technique helps to structure the acrylonitrilebutadiene-styrene polymer (ABS), a mobile extruder head deposits layers of molten material. The layer-by-layer building approach produces highly complex structures that would be impossible to achieve with technologies based on material subtraction, the most frequently employed procedure nowadays. AM has important applications in several areas, including the aircraft and automobile industries, telecommunications, and medicine. [6][7][8] The sol-gel route is a chemical process that involves formation of a sol, namely a colloidal suspension of particles or molecules with liquid character and measuring between 1 and 1000 nm. The sol later goes through a gel phase, which consists of a colloidal system with solid character. In the gel phase, the molecules form a dispersed, continuous, branched, and interpenetrated structure in a system that is usually liquid. After solvent evaporation, the gel phase becomes a solid material that can be either a xerogel, if the solvent is removed by simple evaporation, or an aerogel, if the solvent is removed above its critical temperature and pressure. 9-12The sol-gel process is widely employed to prepare glasses and oxides and to modify surfaces. Sol-gel encompasses hydrolysis and condensation of metal alkoxides or semi-metallic precursors under mild conditions, to generate a polymer network. [13][14][15][16][17][18][19] Alkoxides can form homogeneous sols in various solvents and in the p...

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. Over the last decades, the combination of different technologies to search for systems with new properties and features has brought various segments of biological and earth sciences together. Additive manufacturing, known as rapid prototyping, combined with the sol-gel methodology enables the production of novel systems with applications in many scientific fields. In this work, flexible polyamide membranes were obtained by additive manufacturing, functionalized by the sol-gel methodology, and incorporated with the coordination compound between Eu(III) and 1,10-phenanthroline. The presence of vibrations at 1100 cm -1 in the FTIR spectrum of the material, which is a band typical of the Si-O-Si group in the alkoxide employed during the process, confirmed the polyamide membrane functionalization. The thermogravimetric curve showed that a residue remained after heating at 700 o C, which was attributed to SiO 2 . The membrane was highly luminescent, which confirmed incorporation of the Eu 3+ compound into the material and pointed to the possible application of this system as a topical medication for the treatment of skin diseases.Keywords: sol-gel; photodynamic therapy; luminescence; europium III compounds. INTRODUÇÃOA terapia fotodinâmica (TFD) é uma técnica aplicada no tratamento de câncer de pele e que utiliza a luz (radiação eletromagnética) para tal. Resumidamente, a área tratada é exposta a radiação monocromática, região do visível (600 à 800 nm), após a administração de um fotossensibilizador que absorve a radiação e em seguida transfere a energia ao oxigênio molecular, gerando espécies reativas de oxigênio e, consequentemente, a oxidação dos lipídios, aminoácidos e proteínas, o que resulta na destruição do tumor.1,2 A técnica TFD utiliza emulsões, microemulsões, nanoemulsões, que são aplicadas diretamente sobre a pele e, após um determinado tempo, são absorvidas pelas células tumorais. A literatura tem relatado a utilização de vários sistemas que contém nanopartículas e fotossensibilizados. [3][4][5] Os elementos lantanídeos apresentam, como uma de suas principais carcterísticas, a propriedade fotoluminescentes, amplamente aplicadas na geração de radiação eletromagnética nas regiões do visível e infravermelho. As transições interconfiguracionais f -f são as responsáveis por essas propriedades.6-8 Os íons lantanídeos podem sofrer excitação nas regiões do ultravioleta, visível e infravermelho, o que resulta em linhas de emissão monocromáticas na região do visível e do infravermelho. Por exemplo, o íon Eu 3+ apresenta intensa emissão na região vermelha do espectro eletromagnético, aproximadamente em 620 nm, quando excitado no ultravioleta (394 nm) e visível (460 nm).9-11 A combinação de elementos adequados também pode apresentar alta eficiência de emissão na região do visível quando se utiliza a radiação infravermelha, chamado de conversão ascendente, como por exemplo o par Yb 3+ -Tm 3+. 12 Portanto, os íons lantanídeos apresentam características para serem utilizados como emissores de radiação na região visíve...