Banca de QUALIFICAÇÃO: SILVANA DE SOUSA RÊGO MASCARENHAS DE MENEZES

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE: SILVANA DE SOUSA RÊGO MASCARENHAS DE MENEZES
DATA: 02/12/2025
HORA: 08:30
LOCAL: Online
TÍTULO: COMPARATIVE ANALYSIS OF HYDROGELS BASED ON CASHEW GUM, WITH UREA, IN MAIZE CULTIVATION UNDER GREENHOUSE CONDITIONS
PALAVRAS-CHAVES: polímeros; polissacarídeos; reticulação; fertilizante; agricultura
PÁGINAS: 40
GRANDE ÁREA: Engenharias
ÁREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
ESPECIALIDADE: Polímeros, Aplicações
RESUMO:

The cashew gum, a natural polysaccharide extracted from the cashew tree (Anacardium occidentale), presents substantial potential as a raw material for the synthesis of superabsorbent hydrogels, contributing to the bioeconomy and strengthening sustainable production chains in semi-arid regions, especially in Brazil. In this study, the application of a cashew gum–based hydrogel in maize cultivation under greenhouse conditions was evaluated and compared with the performance of a commercial hydrogel, both with and without the addition of urea. FTIR characterization confirmed the presence of hydrophilic functional groups relevant to water absorption, while thermogravimetric analysis (TG/DTG) demonstrated good thermal stability, particularly in the natural formulations. Swelling tests revealed a higher water absorption capacity for the cashew gum hydrogel, supporting its efficiency in supplying water to plants. The agronomic variables assessed at the end of the growth cycle (77 days after planting) included plant height, biomass, and the number of live and dead leaves. Statistical analysis was performed using SISVAR (version 5.0) with Tukey’s test (P < 0.05). The treatments containing hydrogel significantly increased plant height and biomass, with the commercial hydrogel combined with urea being the most effective for these parameters (6.77% taller and 5.21% higher biomass compared to the natural hydrogel; 20.34% taller and 14.43% higher biomass compared to the control). In contrast, the cashew gum hydrogel promoted greater foliar vitality, with a higher number of live leaves and fewer dead leaves, indicating greater water stability within the root zone. Thus, by integrating agronomic performance with structural, thermal, and hydrodynamic properties, it is concluded that the cashew gum hydrogel represents a sustainable alternative to synthetic hydrogels, standing out for its biodegradability and its potential to improve water-use efficiency in agricultural systems.

MEMBROS DA BANCA:
Presidente - 1553988 - EDSON CAVALCANTI DA SILVA FILHO
Externo ao Programa - 2011596 - RICARDO LOIOLA EDVAN
Externo à Instituição - 660.***.***-72 - LEILSON ROCHA BEZERRA - UFCG
Externo à Instituição - 952.***.***-20 - RAFAEL FELIPPE RATKE - UFMS