Flexibility improvement of short glass fiber reinforced epoxy by using a liquid elastomer

2003-03-17
Kaynak, Cevdet
Tincer, Teoman
In certain applications of fiber reinforced polymer composites flexibility is required. The aim of this study was to improve flexibility of short glass fiber reinforced epoxy composites by using a liquid elastomer. For this purpose, diglycidyl ether of bisphenol-A (DGEBA) based epoxy matrix was modified with hydroxyl terminated polybutadiene (HTPB). A silane coupling agent (SCA) was also used to improve the interfacial adhesion between glass fibers and epoxy matrix. During specimen preparation, hardener and HTPB were premixed and left at room temperature for an hour before mixing with epoxy resin to allow possible reactions to occur. In order to compare flexibility of the specimens flexural tests were conducted and the data were evaluated numerically by using a derived relation. Test data and scanning electron microscope analysis indicated that surface treatment of glass fibers with SCA, and HTPB modification of epoxy matrix improved flexural properties especially due to the strong interaction between fibers, epoxy, and rubber. It was also observed that HTPB modification resulted in formation of relatively round rubber domains in the epoxy matrix leading to increased flexibility of the specimens.

Suggestions

Ultrasonic (C-scan) and microscopic evaluation of resin transfer molded epoxy composite plates
KAŞ, Y. ONUR; Kaynak, Cevdet (Elsevier BV, 2005-02-01)
One of the main problem in resin transfer molding (RTM) is the formation of microvoids decreasing the mechanical performance of the components. In this study, an ultrasonic inspection method (C-scan) was used to evaluate these microvoids. Composite sample plates were produced by a small laboratory size RTM machine injecting epoxy resin into a flat mold filled with woven carbon fiber layers. In C-scan analysis a certain value of energy loss (dB loss) was selected as the 'operator set level' and further dB lo...
MECHANICAL-PROPERTIES OF SURFACE-MODIFIED BAUXITE FILLED SBR VULCANIZATES .1.
ULKEM, I; AKOVALI, G (Elsevier BV, 1994-05-01)
The ultimate properties of rubber products are strongly influenced by the size, size distribution, structure, surface area and surface selectivity of fillers. In this study, natural bauxite was coated with plasma polymer (polystyrene or polybutadiene) to modify surface properties. The coated and uncoated bauxites were tested as filler for SBR vulcanizates, using static and dynamic mechanical methods. The fracture surfaces of the vulcanizates were investigated by SEM. Plasma polymer modified bauxite loaded m...
Furoxan Derivatives of Pyrene - A DFT Study
Türker, Burhan Lemi (Informa UK Limited, 2018-01-01)
Furoxan-fused pyrenes and their dinitroso derivatives (obtained by furoxan ring opening) are considered for density functional treatment at the level of B3LYP/6-31G(d,p). Embedded benzofuroxan moiety in the furoxan-fused pyrene system is thought to undergo ring opening and reclosure process analogously to benzofuroxan itself. The stabilities, structural features, NICS(0) values, IR, and UV-VIS spectral aspects, etc., are investigated comparatively for these isomeric furoxan-fused pyrenes and their isomeric ...
Characteristics of dual-type electrochromic devices based on poly(ethylene oxide) copolymers
Yildiz, Huseyin Bekir; Sahin, Elif; Çırpan, Ali; Toppare, Levent Kamil; Yagci, Yusuf (Wiley, 2007-05-01)
Dual-type polymer electrochromic devices based on [(3-thienyl)methylmethacrylate]-co-[p-vinyl benzyloxy poly(ethylene oxide)]/polythiophene and thiophene-capped poly(ethylene oxide)/polythiophene and ethylene dioxythiophene were constructed via electropolymerization. Spectroelectrochemistry, switching ability and stability of the devices were investigated using UV-visible spectrophotometry and cyclic voltammetry. These devices exhibit low switching; voltages and short switching times with reasonable switchi...
Mechanical Performance of Resol Type Phenolic Resin/Layered Silicate Nanocomposites
Tasan, C. Cem; Kaynak, Cevdet (Wiley, 2009-03-01)
Clay addition has been shown to affect polymer resins positively in terms of several physical and chemical properties, including mechanical performance, high temperature endurance and durability. These increases are limited only to relatively low concentrations of reinforcement phase, but at these low concentrations polymer/layered silicate nanocomposites (P/LS NC) have shown to exhibit higher mechanical performance than fiber reinforced polymer composites. This is among the several reasons that make P/LS N...
Citation Formats
C. Kaynak and T. Tincer, “Flexibility improvement of short glass fiber reinforced epoxy by using a liquid elastomer,” Polymer, pp. 2433–2439, 2003, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/46008.