The mechanical properties of epoxy resins

Yamini, Salim; Young, Robert J.

doi:10.1007/bf00550602

Cited by 124 publications

(26 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Consequently, the thermo-mechanical properties of the tested epoxy resin differ from moderately cross-linked thermosets and from thermoplastics but the physical origins of the plastic flow, softening, and re-hardening can be similar (Yamini and Young, 1980). However, the highly cross-linked RTM6 epoxy resin prematurely fails under most loading conditions other than compression while moderately cross-linked polymers can still exhibit some ductility under tensile and shear loading conditions.…”

Section: Experimental Parameters Identificationmentioning

confidence: 94%

A large strain hyperelastic viscoelastic-viscoplastic-damage constitutive model based on a multi-mechanism non-local damage continuum for amorphous glassy polymers

Nguyễn

Lani

Pardoen

et al. 2016

International Journal of Solids and Structures

View full text Add to dashboard Cite

A large strain hyperelastic phenomenological constitutive model is proposed to model the highly nonlinear, rate-dependent mechanical behavior of amorphous glassy polymers under isothermal conditions. A corotational formulation is used through the total Lagrange formalism. At small strains, the viscoelastic behavior is captured using the generalized Maxwell model. At large strains beyond a viscoelastic limit characterized by a pressure-sensitive yield function, which is extended from the Drucker-Prager one, a viscoplastic region follows. The viscoplastic flow is governed by a non-associated Perzyna-type flow rule incorporating this pressure-sensitive yield function and a quadratic flow potential in order to capture the volumetric deformation during the plastic process. The stress reduction phenomena arising from the post-peak plateau and during the failure stage are considered in the context of a continuum damage mechanics approach.The post-peak softening is modeled by an internal scalar, so-called softening variable, whose evolution is governed by a saturation law. When the softening variable is saturated, the rehardening stage is naturally obtained since the isotropic and kinematic hardening phenomena are still developing. Beyond the onset of failure characterized by a pressure-sensitive failure criterion, the damage process leading to the total failure is controlled by a second internal scalar, so-called failure variable. The final failure occurs when the failure variable reaches its critical value. To avoid the loss of solution uniqueness when dealing with the continuum damage mechanics formalism, a non-local implicit gradient formulation is used for both the softening and failure variables, leading to a multi-mechanism non-local damage continuum. The pressure sensitivity considered in both the yield and failure conditions allows for the distinction under compression and tension loading conditions. It is shown through experimental comparisons that the proposed constitutive model has the ability to capture the complex behavior of amorphous glassy polymers, including their failure.

show abstract

Section: Experimental Parameters Identificationmentioning

confidence: 94%

A large strain hyperelastic viscoelastic-viscoplastic-damage constitutive model based on a multi-mechanism non-local damage continuum for amorphous glassy polymers

Nguyễn

Lani

Pardoen

et al. 2016

International Journal of Solids and Structures

View full text Add to dashboard Cite

show abstract

“…Hollow spheres used in this study are made of commercial epoxy resin, a thermosetting polymer subjected to crack propagation [14]. In fact, rapid crack propagation (RCP) is observed to be predominant at macroscopic scale to dissipate the available energy stored in the structure [15]. As it is commonly known, most thermosetting polymers have a strain rate and temperature dependence on their mechanical properties (Young's modulus, yield strain) [16,17].…”

Section: Introductionmentioning

confidence: 99%

Experimental Investigation and Discrete Element Modelling of Composite Hollow Spheres Subjected to Dynamic Fracture

Coré

Kopp

Viot

et al. 2017

International Journal of Polymer Science

View full text Add to dashboard Cite

This paper deals with the characterization and the numerical modelling of the collapse of composite hollow spherical structures developed to absorb energy during high velocity impacts. The structure is composed of hollow spheres ( = 2-30 mm) made of epoxy resin and mineral powder. First of all, quasi-static and dynamic (V = 5 mm⋅min −1 to V = 2 m⋅s −1 ) compression tests are conducted at room temperature on a single sphere to study energy dissipation mechanisms. Fracture of the material appears to be predominant. A numerical model based on the discrete element method is investigated to simulate the single sphere crushing. The stress-strain-time relationship of the material based on the Ree-Eyring law is numerically implemented. The DEM modelling takes naturally into account the dynamic fracture and the crack path computed is close to the one observed experimentally in uniaxial compression. Eventually, high velocity impacts (V > 100 m⋅s −1 ) of a hollow sphere on a rigid surface are conducted with an air cannon. The numerical results are in good agreement with the experimental data and demonstrate the ability of the present model to correctly describe the mechanical behavior of brittle materials at high strain rate.

show abstract

“…[1][2][3][4][5][6][7] To overcome these drawbacks, many types of polymer-filler composites have been developed, in which the epoxy resins are reinforced with modifying agents, such as fillers, polyhedral oligosilsesquioxanes (POSS), dendrimers etc. [8][9][10][11][12][13][14][15][16][17][18] Polyhedral oligomeric silsesquioxanes (POSS), (RSiO 1.5 ) n with n = 6, 8, 10 ...., are nanoplatforms with 1 to 8 reactive or nonreactive organofunctional groups (R) anchored to the possible eight vertexes of the cubic silsesquioxane.…”

Section: Introductionmentioning

confidence: 99%

Relationship between the dielectric and mechanical properties and the ratio of epoxy resin to hardener of the hybrid thermosetting polymers

Filho¹,

Aquino²,

Pires³

et al. 2006

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

Foi investigada a relação entre as propriedades dielétricas (constante dielétrica, ε'; fator de perda, ε"; energia de ativação, E a ) e a proporção de resina epóxi (OG) para endurecedor em polímeros termorrígidos de resina epóxi (OG). A amplitude do pico de ε" decresce com o aumento da porcentagem em massa de OG até aproximadamente 73% e aumenta levemente para maiores % OG. A temperatura da posição do pico de ε" aumenta com o aumento da % OG, alcançando valores máximos para formulações no intervalo de 67 a 73%, e então, decresce acentuadamente para maiores % OG. A energia de ativação obtida por relaxação dielétrica aumentou com a % OG até aproximadamente 70%. Um aumento adicional na % OG até 83% reduz a E a . As curvas das propriedades mecânicas de módulo de tensão e resistência à fratura como função da % em massa de OG apresentaram um comportamento similar.The relationship between the dielectric properties (dielectric constant, ε', and loss factor, ε"; activation energy, E a ) and the ratio of epoxy resin (OG) to hardener of the epoxy resin thermosetting polymers was investigated. The amplitude of the ε" peak decreases with increasing OG content until about 73 wt.% and slightly increases at higher OG content. The temperature of the position of the ε" peak increases with the increasing of OG content, reaching maximum values for compositions in the range of 67 and 73 wt.%, and then it decreases sharply at higher OG content. The activation energy obtained from dielectric relaxation increased with increasing wt.% OG up to around 70 wt.%. Further increase in concentration of OG up to 83 wt.% reduced E a . The curves of tensile modulus and fracture toughness mechanical properties as a function of OG content presented a similar behavior.

show abstract

The mechanical properties of epoxy resins

Cited by 124 publications

References 17 publications

A large strain hyperelastic viscoelastic-viscoplastic-damage constitutive model based on a multi-mechanism non-local damage continuum for amorphous glassy polymers

A large strain hyperelastic viscoelastic-viscoplastic-damage constitutive model based on a multi-mechanism non-local damage continuum for amorphous glassy polymers

Experimental Investigation and Discrete Element Modelling of Composite Hollow Spheres Subjected to Dynamic Fracture

Relationship between the dielectric and mechanical properties and the ratio of epoxy resin to hardener of the hybrid thermosetting polymers

Contact Info

Product

Resources

About