The Degradation of Mechanical Properties in Halloysite Nanoclay-Polyester Nanocomposites Exposed in Seawater Environment

Abstract

Polyester based polymers are extensively used in aggressive marine environments; however, inadequate data is available on the effects of the seawater on the polyester based nanocomposites mechanical properties. This paper reports the effect of seawater absorption on the mechanical properties degradation of halloysite nanoclay-polyester nanocomposites. Results confirmed that the addition of halloysite nanoclay into polyester matrix was found to increase seawater uptake and reduce mechanical properties compared to monolithic polyester. The maximum decreases in microhardness, tensile and flexural properties, and impact toughness were observed in case of 1 wt% nanoclay. The microhardness decreased from 107 HV to 41.7 HV (61% decrease). Young’s modulus decreased from 0.6 GPa to 0.4 GPa (33% decrease). The flexural modulus decreased from 0.6 GPa to 0.34 GPa (43% decrease). The impact toughness dropped from 0.71 kJ/m2to 0.48 kJ/m2(32% decrease). Interestingly, the fracture toughnessKICincreased with the addition of halloysite nanoclay due to the plasticization effect of the resin matrix. SEM images revealed the significant reduction in mechanical properties in case of 1 wt% reinforcement which is attributed to the degradation of the nanoclay-matrix interface influenced by seawater absorption and agglomeration of halloysite nanoclay.

The Processing of Epoxy/1 wt%-graphene Nanocomposites: Effects of Ethanol on Flexural Properties

“…10 (a)), the crack propagates in straight lines when the maximum load is reached. The crack moves without diversions and this can be associated with lower resistance which is very typical for unreinforced epoxy [21]. Fig.…”

Effect of Short Term Water Exposure on the Mechanical Properties of Halloysite Nanotubes-Multi Layer Graphene Reinforced Polyester Nanocomposites

“…The large standard deviations for monolithic polyester indicate porosity within the samples. That shows air entrapment during processing [37]. Another reason for this could be the quick curing of polyester resin as the volatiles could not escape during curing [38,39].…”

Biodegradation of Halloysite Nanotubes-Polyester Nanocomposites Exposed to Short Term Seawater Immersion

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