A5101995681- Epoxy Resin Curing Processes
- Synthesis and properties of polymers
- Polymer crystallization and properties
- Thermal and Kinetic Analysis
- Photopolymerization techniques and applications
- Mechanical Behavior of Composites
- Injection Molding Process and Properties
- Phase Equilibria and Thermodynamics
- Chemical Thermodynamics and Molecular Structure
- Advanced Polymer Synthesis and Characterization
- Polymer composites and self-healing
- Polymer Synthesis and Characterization
- Thermodynamic properties of mixtures
- Cutaneous lymphoproliferative disorders research
- Physical Education and Gymnastics
- Gas Sensing Nanomaterials and Sensors
- Viral-associated cancers and disorders
- Academic Research in Diverse Fields
- Agriculture and Rural Development Research
- Polymer Nanocomposites and Properties
- Nasal Surgery and Airway Studies
- Energetic Materials and Combustion
- Healthcare during COVID-19 Pandemic
- Fungal Infections and Studies
- Fiber-reinforced polymer composites
Pontifícia Universidade Católica de Minas Gerais
2023
Universidade da Coruña
1994-2001
Universidade de Santiago de Compostela
1992-1994
The characteristics of sorption and diffusion water in an amine-cured epoxy system based on tetraglycidyl diaminodiphenylmethane a novolac glycidyl ether resin were studied as function both the polymer microstructure, known from previous works, temperature. Water-sorption experiments dynamic mechanical analysis (DMA) performed. Tensile stress–strain Rockwell hardness tests conducted to investigate effects absorbed properties material. Competing free volume strong interactions between...
Among the different types of biostimulators used in global market, polymethylmethacrylate (PMMA) biostimulation has been considered most effective truly stimulating clinically visible neocollagenesis.Many histological and clinical studies have also proven product’s safety, addition to its efficacy.The described technique proposes use 10% PMMA for treatment skin flaccidity caused by aging process at degrees. This publication suggests a standardization five pre-determined regions that...
Using differential scanning calorimetry (DSC), we have studied, under isothermal and dynamic conditions, the kinetics of cure reaction for an epoxy resin based on diglycidyl ether bisphenol A (DGEBA) modified with different contents acrylonitrile–butadiene–styrene (ABS) cured 1,3-bisaminomethylcyclohexane (1,3-BAC). Kinetic analysis were performed using three kinetic models: Kissinger, Flynn–Wall–Ozawa, phenomenological model Kamal as a result its autocatalytic behavior. Diffusion control is...
Abstract By employing differential scaning calorimetry, DSC, we have studied, under isothermal conditions, the kinetics of cure reaction for a system containing diglycidyl ether bisphenol A (DGEBA) and 1,3‐bisaminomethylcyclohexane (1,3‐BAC) as curing agent, over temperature range 60–110°C. We determined conversions reached at several temperatures rates. The experimental data, showing an autocatalytic behavior, were compared with model proposed by Kamal, which includes two rate constants, k...
Using dynamic mechanical analysis (DMA) we have studied the variation with frequency of properties (storages modulus,E'; loss modulus,E'' and tangent or tan σ) for a system containg diglycidyl ether bisphenol A (DGEBA) 1,3-bisaminomethylcyclohexane (1,3-BAC). These were measured both in glass transition β regions. An increase caused shift σ peak positions regions toward higher temperature. Finally, report activation energies DGEBA/1,3-BAC expoxy α transitions.
Times to gelation and vitrification have been determined at different isothermal curing temperatures between 200 240°C for an epoxy/amine system containing both tetraglycidyl-4,4′-diaminodiphenylmethane (TGDDM) a multifunctional Novolac glycidyl ether with 4,4′-diaminodiphenylsulphone (DDS). The mixture was rich in epoxy, amine/epoxide ratio of 0·64. Gelation occurred around 44% conversion. Vitrification from data curves glass transition temperature, Tg, versus time obtained differential...
The isothermal cure of an epoxy-cycloaliphatic amine system has been studied following the evolution both glass transition temperature and conversion. A functional relationship between Tg conversion is established. reaction satisfactorily described by a phenomenological model with parameters determined from DSC experiments. By applying kinetic model, gelation vitrification curves are calculated compared experimental times to at temperatures 50 100°C. time-temperature-transformation (TTT)...
Abstract Times to gelation and times vitrification during isothermal curing for the epoxy system diglycidyl ether of bisphenol A 1,3‐bisaminomethyl‐cyclohexane were measured at different temperatures between 50 100°C. Gelation occurs around 56% conversion. Vitrification was determined from data curves glass transition temperature, T g , versus time obtained DSC experiments. The minimum maximum this go = −37°C g∞ 150°C. Values activation energy epoxy/amine cure reaction 58 kJ/mol 49.5 shift...
Differential scanning calorimetry (DSC) was applied to study the cure kinetics of an epoxy system containing both tetraglycidyl 4,4′-diaminodiphenylmethane (TGDDM) and a multifunctional Novolac glycidyl ether resin, cured with 4,4′-diaminodiphenylsulfone (DDS). The experimental data were analyzed in terms mechanistic model proposed by Cole, which includes etherification reaction. can be completely described three rate constants, obey Arrhenius relationship. This gives good description up...