Cure kinetics, morphological and dynamic mechanical analysis of diglycidyl ether of bisphenol-A epoxy resin modified with hydroxyl terminated poly(ether ether ketone) containing pendent tertiary butyl groups

Carrier Fibers for the Safe Dosage of Nanoparticles in Nanocomposites: Nanomechanical and Thermomechanical Study on Polycarbonate/Boehmite Electrospun Fibers Embedded in Epoxy Resin

The reinforcing effect of boehmite nanoparticles (BNP) in epoxy resins for fiber composite lightweight construction is related to the formation of a soft but bound interphase between filler and polymer. The interphase is able to dissipate crack propagation energy and consequently increases the fracture toughness of the epoxy resin. Usually, the nanoparticles are dispersed in the resin and then mixed with the hardener to form an applicable mixture to impregnate the fibers. If one wishes to locally increase the fracture toughness at particularly stressed positions of the fiber-reinforced polymer composites (FRPC), this could be done by spraying nanoparticles from a suspension. However, this would entail high costs for removing the nanoparticles from the ambient air. We propose that a fiber fleece containing bound nanoparticles be inserted at exposed locations. For the present proof-of-concept study, an electrospun polycarbonate nonwoven and taurine modified BNP are proposed. After fabrication of suitable PC/EP/BNP composites, the thermomechanical properties were tested by dynamic mechanical analysis (DMA). Comparatively, the local nanomechanical properties such as stiffness and elastic modulus were determined by atomic force microscopy (AFM). An additional investigation of the distribution of the nanoparticles in the epoxy matrix, which is a prerequisite for an effective nanocomposite, is carried out by scanning electron microscopy in transmission mode (TSEM). From the results it can be concluded that the concept of carrier fibers for nanoparticles is viable.

Controlling nanodomain morphology of epoxy thermosets templated by poly(caprolactone)-block-poly(dimethylsiloxane)-block-poly(caprolactone) ABA triblock copolymer

In this paper, triblock copolymer was incorporated into epoxy to prepare nano thermosets. After studying the compatibility between polydimethylsiloxane (PDMS), polycaprolactone (PCL) and bisphenol A epoxy resin (E-54), poly(caprolactone)–poly(dimethylsiloxane)–poly(caprolactone) (PCL-b-PDMS-b-PCL) triblock copolymer was incorporated into bisphenol A epoxy resin (E-54) and cured with DDS. A nano structure was formed and the size of the spherical phase became larger with increasing PCL-b-PDMS-b-PCL. According to the fact that TGDDM/PCL was compatible and TGDDM/PDMS was incompatible during the curing reaction, the mechanism of nano structure formation was self-assembly. The factors of influencing nano structure formation were discussed with regard to different curing temperatures and accelerators. Curing kinetics was utilized to study the effect of accelerator on nano structure formation.

FTIR spectrum of PDMS and PCL-b-PDMS-b-PCL triblock copolymer..

Thermal and mechanical properties of azomethine functionalized cyanate ester/epoxy blends

A series of azomethine fictionalized cyanate ester and its epoxy blends were prepared and characterized.

Thermally flexible epoxy/cellulose blends mediated by an ionic liquid

Blends between the widely used thermoset resin, epoxy, and the most abundant organic material, natural cellulose are demonstrated for the first time.

Odd–even effect on the thermal properties of Schiff base functionalized dicyanate esters and thermo-mechanical properties of their blends with epoxy resins

An odd–even effect was observed in the case of dicyanate esters described in this work.