Moisture Diffusion in Silica/Clay/Natural Rubber Hybrid Composites

Abstract

This study investigated moisture diffusion in natural rubber (NR) hybrid composites filled with silica and bentonite clay. Natural bentonite (BNT) was treated with tetradecyldimethylammonium chloride and coco diethanolamide to produce modified bentonite (M-BNT). Varied proportions of silica, M-BNT, and BNT fillers were added to raw NR according to a third-degree simplex lattice mixture design of experiment. The addition of fillers affects the vulcanization characteristics, mechanical properties, and hardness of NR hybrid composites. Moisture diffusion behavior was studied by monitoring the water uptake of NR composites during immersion in deionized water at 80°C. Data from sorption experiments were fitted on the classical Fickian and Langmuir-type diffusion models. The Fickian model overestimates and underestimates the water uptake of NR composites in the early and later stages of moisture diffusion, respectively. On the other hand, the Langmuir-type model adequately captures the anomalous diffusion behavior of moisture in NR composites. Parameters of the Langmuir model (equilibrium water uptake and diffusion coefficient) vary with the composition of hybrid fillers. Optimum proportions of silica, M-BNT, and BNT in rubber composites were obtained by considering the effect of fillers on mechanical properties and moisture diffusion characteristics of NR.

Superhydrophobic, Highly Adhesive, and Corrosion-Protective Fluoropolymer-Modified Polythiophene Coatings

“…This study is motivated by the ongoing demand for more robust and enduring protective coatings in industries where metallic structures constantly face environmentally challenging conditions. Traditional coatings often fall short in providing prolonged defense against water-induced degradation and mechanical abuse. , By synergizing the hydrophobicity of PVDF–HFP and adhesive attributes of the silane coupling agent with the versatile and conductive nature of PTH, a holistic solution poised to transform protective coating applications can be realized. The anticipated outcomes not only extend beyond merely enhancing coating performance and durability but also have broader implications for fostering sustainability and efficiency in various sectors including the construction, automotive, aerospace, and marine industries.…”

Hygrothermal aging and water absorption behavior of radial tire composites

“…[17][18][19] At present, some scholars used experiments to study the water absorption behavior of the rubber composites. [20][21][22] Pajarito et al 23 have investigated moisture diffusion in natural rubber hybrid composites filled with silica and bentonite clay. Data from sorption experiments were fitted on the classical Fickian and Langmuir-type diffusion models.…”