Naiara Lima Costa

Mrs. Naiara Lima Costa

orcid

Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
17 June 2024 in Polymers
Verified
Journal Article
Open access
PDF file
NCNaiara Lima Costa
Naiara Lima Costa
CHCarlos Toshiyuki Hiranobe
Carlos Toshiyuki Hiranobe
HCHenrique Pina Cardim
Henrique Pina Cardim
GDGuilherme Dognani
Guilherme Dognani
JSJuan Sanchez
Juan Sanchez
MSMichael J Silva
Michael J Silva
Ethylene propylene diene monomer (EPDM) is a synthetic rubber widely used in industry and commerce due to its high thermal and chemical resistance. Nanotechnology has enabled the incorporation of nanomaterials into polymeric matrixes that maintain their flexibility and conformation, allowing them to achieve properties previously unattainable, such as improved tensile and chemical resistance. In this work, we summarize the influence of different nanostructures on the mechanical, thermal, and electrical properties of EPDM-based materials to keep up with current research and support future research into synthetic rubber nanocomposites.

28 September 2025 in Recycling
Verified
Journal Article
Open access
PDF file
DSDener Silva Souza
Dener Silva Souza
RSRICARDO DOS SANTOS
RICARDO DOS SANTOS
MSMarcos Alves dos Santos
Marcos Alves dos Santos
GSGleyson Tadeu de Almeida Santos
Gleyson Tadeu de Almeida Santos
NCNaiara Lima Costa
Naiara Lima Costa
RSRENIVALDO José SANTOS
RENIVALDO José SANTOS
This study presents, for the first time, a systematic investigation of the use of micronized post-consumer silica gel as a reinforcing filler in natural rubber composites, in direct comparison with commercial silicas. Thirteen formulations were prepared using three types of silica (recycled, Copasil, and ZC-185P) and three coupling agents (TESPT, VTMO, and Chartwell C-515.71HR®). The recycled silica exhibited high purity (97.33% Si) and irregular morphology but resulted in lower crosslink density (0.47–0.59 × 10−4 mol·cm−3) and inferior mechanical performance, with tensile strength up to 7.9 MPa and high abrasion loss (878–888 mm3). In contrast, ZC-185P silica combined with TESPT achieved the best results, with a tensile strength of 18.5 MPa, tear resistance of 99.36 N·mm−1, and minimum abrasion loss of 170 mm3. Although less efficient in reinforcement, composites containing recycled silica were successfully applied in the production of a functional rubber mat, demonstrating their practical viability. The results confirm the potential for valorization of spent silica gel as an alternative raw material for sustainable composites, contributing to the circular economy.

1 January 2026 in Materials Research
Verified
Journal Article
Open access
NCNaiara Lima Costa
Naiara Lima Costa
JCJúnior da Silva Camargo
Júnior da Silva Camargo
WGWillian Pereira Gomes
Willian Pereira Gomes
DSDENER SILVA SOUZA
DENER SILVA SOUZA
CACláudia Gonçalves de Azevedo
Cláudia Gonçalves de Azevedo
MSMichael J Silva
Michael J Silva
In response to the increasing global demand for energy, this study investigates the pyrolysis kinetics of macrophyte Eleocharis Elegans (MEE) as a potential renewable resource. Thermogravimetric analyses were performed at heating rates of 5, 10, 20, and 40 °C min−1 to better understand its thermal behavior. The physicochemical characterization revealed properties comparable to common agro-industrial residues, including a high volatile matter content (61.92%), relatively low ash content (17.87%), and an intermediate calorific value (16.15 MJ kg−1), indicating its suitability for energy applications. Morphological analysis of the resulting ash showed irregular and agglomerated particles, while energy-dispersive spectroscopy (EDS) indicated a predominance of silicon dioxide. The TGA/DTG curves exhibited three distinct stages of thermal decomposition, consistent with the degradation of lignocellulosic components. Kinetic parameters were determined using the Flynn–Wall–Ozawa (FWO), Kissinger–Akahira–Sunose (KAS), and Starink methods, which showed strong agreement. The highest Ea value (194 kJ mol−1) was observed in the main decomposition stage. Furthermore, thermodynamic analysis indicated that pyrolysis occurred under non-spontaneous conditions with continuous heat supply, primarily due to the overlapping degradation of hemicellulose and cellulose. Overall, the results highlight the potential of MEE as a promising biomass for thermochemical energy conversion.

Verified
Journal Article
Open access
PDF file
SKSamara Araújo Kawall
Samara Araújo Kawall
NGNuelson Carlitos Gomes
Nuelson Carlitos Gomes
DMDiego Silva de Melo
Diego Silva de Melo
DSDener Silva Souza
Dener Silva Souza
RSRICARDO DOS SANTOS
RICARDO DOS SANTOS
RSRENIVALDO José SANTOS
RENIVALDO José SANTOS
This study evaluated the partial and total replacement of zinc oxide (ZnO) with magnesium oxide (MgO) in styrene–butadiene rubber (SBR) composites, as well as the incorporation of ground tire rubber (GTR), aiming to develop more sustainable elastomer formulations. Ten formulations were prepared with varying ZnO/MgO ratios (100/0 to 0/100), with and without 20 phr of GTR. The composites were characterized by particle size distribution, morphology, rheometric behavior, density, crosslink density, mechanical properties, abrasion resistance, compression behavior, and thermo-oxidative aging. The results showed that hybrid ZnO/MgO activation systems exhibited a synergistic effect, enhancing vulcanization kinetics and mechanical performance compared to single-activator systems. Total replacement of ZnO by MgO was less effective, leading to reduced crosslink density and inferior properties. The addition of GTR increased compound viscosity and altered morphology but improved abrasion and compression resistance without significantly affecting tensile strength. Aging tests indicated good thermal stability, with maintenance or improvement of tensile properties due to post-curing effects. Overall, the combination of reduced ZnO content with MgO and GTR represents a viable approach for producing SBR composites with adequate performance and lower environmental impact.

Verified
Journal Article
Open access
PDF file
DSDener Silva Souza
Dener Silva Souza
MBMaria Claudia Botan
Maria Claudia Botan
RSRICARDO DOS SANTOS
RICARDO DOS SANTOS
MSMichael J Silva
Michael J Silva
GSGleyson Tadeu de Almeida Santos
Gleyson Tadeu de Almeida Santos
RSRENIVALDO José SANTOS
RENIVALDO José SANTOS
This study investigates the incorporation of toner residue (TR), derived from post-consumer printing cartridges, as an alternative filler in styrene–butadiene rubber (SBR) composites, with emphasis placed on solid waste valorization and the promotion of a circular economy. TR consists predominantly of fine particles containing thermoplastic polymers, carbon black, metal oxides, and additives, exhibiting functional potential as a partially reinforcing filler material. Composites containing 0 to 50 phr of TR were prepared and characterized in terms of rheometric properties, dispersion degree, elemental composition by X-ray fluorescence (XRF), crosslink density, scanning electron microscopy (SEM), infrared spectroscopy, Shore A hardness, abrasion resistance, tensile strength, and tear resistance. Rheometric results indicated modifications in vulcanization kinetics and a reduction in maximum torque for formulations with high TR contents, suggesting a possible diluent effect or interference with elastomeric network formation. Conversely, moderate TR concentrations promoted increased hardness, improved tensile strength, and higher crosslink density, associated with adequate particle dispersion within the matrix, as confirmed by SEM analysis. However, excessive TR loading led to increased abrasion loss and an overall reduction in mechanical performance. It is concluded that TR demonstrates technical feasibility as a partial substitute for conventional fillers in SBR composites, with potential industrial application, such as in footwear sole prototypes, combining functional performance with environmental impact mitigation.

18 December 2023 in Proceeding Series of the Brazilian Society of Computational and Applied Mathematics
Verified
Conference Paper
Open access
PDF file
LSLilian E. da Silva
Lilian E. da Silva
MCMarilaine Colnago
Marilaine Colnago
Giovana Augusta BenvenutoGiovana Augusta Benvenuto
Giovana Augusta Benvenuto
NCNaiara Lima Costa
Naiara Lima Costa
SLSamantha Lanzelotti
Samantha Lanzelotti
WCWallace Casaca
Wallace Casaca
A programação é uma habilidade fundamental na indústria de tecnologia e permite que as pessoas criem soluções para vários problemas em diferentes áreas. As mulheres ainda estão sub- representadas nas áreas STEM, especialmente nas relacionadas à tecnologia. A exposição precoce à programação pode ajudar as meninas a desenvolver suas habilidades de resolução de problemas e pensamento crítico, e também pode despertar seu interesse em seguir uma carreira na área. Como consequência de termos mais mulheres na tecnologia, podemos citar a melhoria na diversidade, inovação e criatividade no campo. Além disso, as mulheres podem trazer perspectivas e abordagens únicas para resolver problemas, o que pode levar a soluções mais abrangentes e inclusivas. Dessa forma, o presente trabalho tem como objetivo discutir a importância da representatividade feminina nas áreas de tecnologia e da inclusão da programação na vida de meninas e mulheres. Para tal, apresentamos um relato de experiência obtida durante a execução do projeto de extensão GECET: Garotas nas Engenharias, Ciências Exatas e Tecnologias, que consistiu de um jogo criado por uma menina, que conta a história de Ada Lovelace, de modo a enfatizar o papel da educação e do engajamento na promoção da igualdade e diversidade de gênero no campo da tecnologia.