Development of a toughened DGEBS/DDS system toward improved thermal and mechanical properties by the addition of a tetrafunctional epoxy resin and a novel thermoplastic

Abstract

It was the object of the present article to discuss the effect of the addition of a tetrafunctional resin, namely, tetraglycidyl-4,4Ј-diaminodiphenylmethane (TG-DDM), and of a novel 40:60 polyethersulfone:polyetherethersulfone (PES:PEES) copolymer on a blend constituted by a difunctional resin, diglycidyl ether of bisphenol S (DGEBS), and an aromatic ammine, 4,4Ј-diaminodiphenylsulfone (4,4ЈDDS). The formulated blends were fully characterized in terms of the morphology and the viscoelastic and mechanical properties. The modification by the tetrafunctional resin was proved to be a useful means to improve the glass transition temperature and, therefore, to widen the range of the working temperature. The addition of the novel copolymer resulted in a marked increase in toughness without negatively affecting the thermal and elastic properties of the blend. TEM analysis, despite the high amount of thermoplastic used, showed a homogeneous morphology that would lead to the conclusion of the existence of a full-IPN network. Moisture-uptake experiments were conducted both on the blend and on the resins on their own. It was shown that the combination of the difunctional resin with the tetrafunctional led to a decrease of the percent of the water absorbed.

Synthesis and characterization of konjac glucomannan/poly(vinyl alcohol) interpenetrating polymer networks

“…4 IPN materials have drawn much attention because of the special properties brought about by the interlocking of polymer chains. 5 Polyurethane, 6 acrylic acid ester, 7 and epoxy resin 8 are the usual materials for IPNs; however, research on IPN materials from cellulose, 9 poly(vinyl alcohol) (PVA), 10,11 etc. also revealed interesting results.…”

Morphology and contact angle studies of poly(styrene-co-acrylonitrile) modified epoxy resin blends and their glass fibre reinforced composites

“…In recent years, high performance thermoplastics have been extensively used to toughen thermosetting resins because of their high modulus and glass transition temperatures [2][3][4]. Morphology of the resulting polymer blends depends on the selection of the thermoplastic polymer, the epoxy precursors, hardener and on the curing cycle parameters [5][6][7]. The phase separation upon crosslinking is due to the increase in molecular weight of epoxy resin.…”

Radiation Curing of Thermosetting-Thermoplastic Blends as Matrices for Structural Carbon Fibre Composites

“…Among the toughening agents studied for thermally cured systems, the best improvement of toughness, without loosing thermal and mechanical properties, has been obtained by engineering thermoplastics, like poly(ether sulfone), poly(ether imide), poly(aryl ether ketone), poly(phenylene oxide), polyamide etc. (Unnikrishnan & Thachil, 2006;Mimura et al, 2000;Blanco et al 2003, Park & Jin, 2007. The thermoplastic toughened epoxies form homogeneous blends in the uncured state and can lead to phase separation on curing.…”