Effect of amine‐terminated butadiene‐acrylonitrile/clay combinations on the structure and properties of epoxy nanocomposites

Abstract

The effect of the clay content and the method of its combination with amine-terminated butadiene-acrylonitrile (ATBN) on the structure and behavior of epoxy was studied. In the case of the simultaneous addition of both components, the increasing clay content had a very small effect on the size of the reaction-induced phase separationformed particles at 5% rubber content due to predominant elimination of two major clay effects, i.e., the nucleation due to phase separation and the kinetics. As a result, both the time window between the onset of phase separation and vitrification and the viscosity at the cloud point did not change significantly. The minor change in the particle size/clay con-tent dependences with different curing temperatures indicates that the balance between the two clay effects shifted. The corresponding study of the mechanical behavior indicated that the best balanced mechanical properties were obtained at certain clay/ATBN ratios, and thus, there was synergy between the components. Similar mechanical parameters were obtained for the application of both components in the form of ATBN/montmorillonite intercalate.

Epoxy/PCL nanocomposites: Effect of layered silicate on structure and behavior

“…These effects include clay nucleation [25], which leads to an earlier onset of phase separation [36] at lower conversion and viscosity, as well as a longer interval between the onset of phase separation and gelation [11]. These results represent a difference from epoxy/liquid rubber/clay systems [11,12], in which an increase in particle size was found. This difference can be explained by the expected lower significance of the pinning effect of clay on the phase separation of the modifier as a result of the significantly lower molecular weight (i.e., in the system with the less significant asymmetry).…”

“…The primary shortcoming is the increase in viscosity that limits the content of the modifier. An increasing number of studies have indicated not only that nanofillers (NF) can compensate for the stiffness reduction of impact-modified polymeric systems but also that a suitable combination of NF and a polymeric modifier can also provide a synergistic effect (e.g., further increasing the material toughness) [7][8][9][10][11][12][13][14][15][16]. The enhanced efficiency of impact modifiers allows their content to be reduced.…”

“…This effect was observed in both immiscible thermoplastic systems [7][8][9] and epoxies with two phase structures formed by the reaction-induced phase separation (RIPS) [10] of a modifier dissolved in an uncured resin. The enhanced mechanical performance of epoxy systems was mostly observed in liquid rubbers and clays [11][12][13] and in combinations of thermoplastics (PEEK, PEI, PES, ABS) and clays [14][15][16][17][18][19][20]. The synergistic effect of the nanofiller consists in its complex effect on the multiphase system by reinforcement, leading also to a change in the component parameter profile combined with a significant influence on the structure and parameters of the interface.…”

“…The existing studies of epoxy and thermoplastics have focused only on one modifier concentration or a limited composition range, and some lack descriptions of the effects of NF on the structure or fail to evaluate the mechanical behavior. Based on our results indicating the importance of montmorillonite (MMT) content in epoxy and liquid rubber [11,12], this study focuses on a more detailed description of the relationship between the structure and properties of epoxy containing 5-30% PCL. The reason for the choice of semicrystalline PCL with relatively low mechanical behavior is the welldescribed phase behavior [40][41][42] of epoxy/PCL systems and the reported potential to upgrade epoxy [36,37].…”

Effect of halloysite on structure and properties of melt-drawn PCL/PLA microfibrillar composites

“…In some cases, suitable modifications can enhance HNT efficiency [17,18]. However, the evaluation of the structure-directing potential of HNT in polymer [19][20][21][22][23] is in its infancy stage, especially in comparison with that of oMMT [24][25][26][27]. Although the application of PLA and other high performance polyesters in the form of short reinforcing fibres [28,29] in polymer-polymer composites could be a radical alternative to the use PCL/ PLA blends, a significant limitation of this method is the difficult dispersion of compliant fibres in the polymer matrix and their relatively poor adhesion to it [30].…”