Separation of Gelation From Vitrification in Curing of a Fiber - Reinforced Epoxy Composite
نویسنده
چکیده
Prepregs of a mixture of the tetrafunctional epoxy tetraglycidyl 4.4-diaminodiphenyl methane (TGDDM) and the tetrafunctional amine 4.4'-diaminodiphenylsulfone (DDS) were characterized with temperature-modulated DSC (TMDSC) as well as dynamic mechanical analysis (DMA). The baseline shift of the glass transition was separated from the curing exotherm by using temperature-modulated and step scan DSC temperature scans. Likewise, the baseline shift in heat capacity due to vitrification was isolated using TMDSC isotherms. Using the TMDSC glass transition temperature, degree of conversion, and vitrification results, combined with the gelation data generated from DMA, a time-temperature-transformation (TIT) diagram was constructed, providing information necessary for optimization of industrial processing of the epoxy prepreg. Thus, effects of storage, preprocessing, and postprocessing on the overall curing process are taken into account.
منابع مشابه
MECHANICAL CHARACTERIZATION AND ANALYSIS OF RANDOMLY DISTRIBUTED SHORT BANANA FIBER REINFORCED EPOXY COMPOSITES
Short banana fiber reinforced composites have been prepared in laboratory to determine mechanical properties. It has been observed that as soon as the percentage of the banana fiber increases slightly there is a tremendous increase in ultimate tensile strength, % of strain and young modulus of elasticity. Reinforcement of banana fibers in epoxy resin increases stiffness and decreases damping pr...
متن کاملMulti-objective Optimization of Hybrid Carbon/Glass Fiber Reinforced Epoxy Composite Automotive Drive Shaft
In design and fabricate drive shafts with high value of fundamental natural frequency that represented high value of critical speed; using composite materials instead of typical metallic materials could provide longer length shafts with lighter weight. In this paper, multi-objective optimization (MOP) of a composite drive shaft is performed considering three conflicting objectives: fundamental ...
متن کاملExperimental Study of The Mechanical Properties of Banana Fiber and Groundnut Shell Ash Reinforced Epoxy Hybrid Composite
Effect of addition of filler material to the natural fiber composite was experimentally investigated. Composites are manufactured by the conventional hand-layup method. All composites are made with a fixed banana fiber with 15% weight fraction addition of different weight fraction of (0, 3, 5, 7.5%) groundnut shell ash is added to the composite. Tensile, hardness, impact and compressive strengt...
متن کاملA Micromechanics Based Processing Model for the Curing Response of a Unidirectional Fiber Reinforced Composite
A micromechanics based thermal model was developed to predict the temperature and degree of cure (DOC) distribution inside a unidirectional fiber reinforced composite during the curing process. Using the concentric cylinder assemblage (CCA) model as a representation of the composite microstructure, the effective thermodynamic properties of the composite were computed based on the fiber and matr...
متن کاملSolid freeform fabrication of epoxidized soybean oil/epoxy composite with bis or polyalkyleneamine curing agents
Extrusion freeform fabrication has been used to make bars of fiber-reinforced epoxidized soybean oil (ESO)/epoxy resin. Freeform fabrication methods build materials by the repetitive addition of thin layers. The mixture of epoxidized soybean oil (ESO) and epoxy resin are modified with a gelling agent to solidify the materials until curing occurs. The high strength and stiffness composites are f...
متن کامل