Viable Properties of Natural Rubber/Halloysite Nanotubes Composites Affected by Various Silanes

Abstract

Natural rubber (NR) is incompatible with hydrophilic additives like halloysite nanotubes (HNT) due to their different polarity. The silane coupling agent is the ideal component to include in such a compound to solve this problem. Many types of silane are available for polymer composites depending on their functionalities. This work aimed to tune it to the composite based on NR and HNT. Four different silanes, namely Bis[3- (Triethoxysilyl)Propyl]Tetrasulfide (TESPT), 3-Aminopropyl triethoxysilane (APTES), N-[3-(Trimethoxysilyl)Propyl] Ethylenediamine (AEAPTMS), and Vinyltrimethoxysilane (VTMS) were used. Here, the mechanical properties were used to assess the properties, paying close attention to how their reinforcement influenced their crystallization behavior after stretching. It was revealed that adding silane coupling agents greatly improved the composites’ modulus, tensile strength, and tear strength. From the overall findings, AEAPTMS was viable for NR/HNT composites. This was in direct agreement with the interactions between NR and HNT that silanes had encouraged. The findings from stress-strain curves describing the crystallization of the composites are in good agreement with the findings from synchrotron wide-angle X-ray scattering (WAXS). The corresponding silanes have substantially aided the strain-induced crystallization (SIC) of composites.

Effect of Different Silane Coupling Agents In-Situ Modified Sepiolite on the Structure and Properties of Natural Rubber Composites Prepared by Latex Compounding Method

“…In this study, we selected three silane coupling agents with different functional groups (see Table 1 ) to modify sepiolite. Our modification mechanism [ 38 , 39 , 40 ] involved the hydrolysis of Si–O–C 2 H 5 in the silane coupling agent and the subsequent condensation of hydroxyl groups on the surface of sepiolite, with C=C in VTES, -HS- in MPTES, and –S 4 – in TESPT all able to participate in the vulcanization process of natural rubber and form strong chemical bonds. Hydrolysis of silane coupling agents is known to be slow, often requiring the addition of acid to promote hydrolysis [ 41 , 42 ] and improve the efficiency of hydroxyl condensation with the inorganic filler surface.…”

Control of halloysite nanotubes localization into a LLDPE/EVA (70/30) blend through specific chemical modifications and sequence of mixing during extrusion

“…The morphology study showed that the size of NBR droplets in TPE nanocomposites was reduced by the presence of halloysite and that its size is even smaller with the modified HNT. More recently, Hayeemasae et al [29] evaluated the grafting effect of respectively the bis Propyl]Tetrasulfide (TESPT), the 3-Aminopropyl triethoxysilane (APTES), the N- Propyl] Ethylenediamine (AEAPTMS), and the Vinyltrimethoxysilane (VTMS) on both the dispersion of HNT and coupling reactions between natural rubber (NR) and HNT. It was observed that the mechanical properties of the corresponding materials were improved by introducing silanes and even more using AEAPTMS.…”