Journal of Mechanical Engineering

Mechanical and Thermal Properties of LENR Modified Epoxy Composite

M A Abu Bakar*
W Kuntjoro
Faculty of Mechanical Engineering
Universiti Teknologi MARA, (UiTM) Shah Alam
*corresponding author / email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it
S Ahmad
School of Applied Physics
Faculty of Science & Technology
Universiti Kebangsaan Malaysia, UKM Bangi

ABSTRACT
Epoxy resins are considered as one of the most important classes of thermosetting
polymers for many industrial applications and become an important matrix in
polymer composites. However polymerization of this resin resulted in brittleness
due to high crosslinking level. Due to this matter, many efforts have been made to
improve the toughness of cured epoxy resins by the introduction of rigid particles,
reactive rubbers, interpenetrating polymer networks and thermoplastics within
the matrix. Incorporation of small amount of rubber is one of the approaches to
improve fracture toughness of the epoxy matrix. In this work, the flexural and
impact properties of liquid epoxidized natural rubber (LENR) modified epoxy
composites have been studied. Addition of LENR increased the impact strength
of the epoxy resin. The impact strength increased from to 18.357 kJ/m2, when
modified with 5.5 phr LENR. The SEM analysis shows uniform dispersion of
rubber particles within the epoxy matrix with average particle size less than
1 ?m.

Keywords: Epoxy resin, modified epoxy, liquid epoxidized natural rubber
(LENR), impact strength, toughened epoxy

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