Critical rubber layer thickness of core-shell particles with a rigid core and a soft shell for toughening of epoxy resins without loss of elastic modulus and strength

Abstract Here, core-shell impact modifier particles (CSIMPs) and multiwalled carbon nanotubes (MWCNs) were used as reinforcing agents for improving toughness and tensile properties of epoxy resin. For this purpose, emulsion polymerization technique was exploited to fabricate poly(butyl acrylate-allyl methacrylate) core- poly(methyl methacrylate-glycidyl methacrylate) shell impact modifier particles with average particle size of 407 nm. It was revealed that using a combination of the prepared CSIMPs and MWCNTs could significantly enhance toughness and tensile properties of epoxy resin. Also, it was observed that the dominant factors in enhancing the fracture toughness of the ternary composites are crack deflection/arresting as well as enlarged plastic deformation around the growing crack tip induced by the combination of rigid and soft particles. The Response Surface Methodology (RSM) with central composite design (CCD) was utilized to study the effects of the amounts of core-shell particles and multiwalled carbon nanotubes on the toughness and tensile properties of epoxy resin. The proposed quadratic models were in accordance with the experimental results with correlation coefficient more than 98%. The optimum condition for maximum toughness, elastic modulus, and tensile strength were 3 % wt. MWCNT and 1.03 % wt. CSIMPs. The sample fabricated in optimal condition indicated toughness, elastic modulus, and tensile strength equal to 2.2 MPa. m1/2, 3014.5 MPa and 40.6 MPa, respectively.

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Core-shell particles designed for toughening the epoxy resins. II. Core-shell-particle-toughened epoxy resins

Journal of Applied Polymer Science ◽

10.1002/(sici)1097-4628(19981219)70:12<2313::aid-app2>3.0.co;2-p ◽

1998 ◽

Vol 70 (12) ◽

pp. 2313-2322 ◽

Cited By ~ 68

Author(s):

King-Fu Lin ◽

Yow-Der Shieh

Keyword(s):

Epoxy Resins ◽

Core Shell ◽

Shell Particle ◽

Toughened Epoxy ◽

Shell Particles

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Magnetic Properties of Fe3O4/CoFe2O4 Composite Nanoparticles with Core/Shell Architecture

Ukrainian Journal of Physics ◽

10.15407/ujpe65.10.904 ◽

2020 ◽

Vol 65 (10) ◽

pp. 904

Author(s):

V. O. Zamorskyi ◽

Ya. M. Lytvynenko ◽

A. M. Pogorily ◽

A. I. Tovstolytkin ◽

S. O. Solopan ◽

...

Keyword(s):

Magnetic Properties ◽

Spinel Ferrite ◽

Composite Nanoparticles ◽

Core Shell ◽

Cofe2o4 Nanoparticles ◽

Core Diameter ◽

The Core ◽

Shell Particles ◽

Interface Parameters ◽

Shell Composite

Magnetic properties of the sets of Fe3O4(core)/CoFe2O4(shell) composite nanoparticles with a core diameter of about 6.3 nm and various shell thicknesses (0, 1.0, and 2.5 nm), as well as the mixtures of Fe3O4 and CoFe2O4 nanoparticles taken in the ratios corresponding to the core/shell material contents in the former case, have been studied. The results of magnetic research showed that the coating of magnetic nanoparticles with a shell gives rise to the appearance of two simultaneous effects: the modification of the core/shell interface parameters and the parameter change in both the nanoparticle’s core and shell themselves. As a result, the core/shell particles acquire new characteristics that are inherent neither to Fe3O4 nor to CoFe2O4. The obtained results open the way to the optimization and adaptation of the parameters of the core/shell spinel-ferrite-based nanoparticles for their application in various technological and biomedical domains.

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