Effects of functionalized halloysite on morphology and properties of polyamide-11/SEBS-g-MA blends

Abstract

Halloysite nanotubes (HNTs) were functionalized by grafting styrene-ethylene-butylene-styrene (SEBS) copolymer chains after a two-step modification procedure. Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA) and pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) were used to determine the grafting rate. Then, raw and functionalized halloysites were incorporated into polyamide-11(PA11)/ styrene-ethylene-butylene-styrene grafted maleic anhydride (SEBS-g-MA) blends (85/15 w/w). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) micrographs show a good dispersion of both halloysites particles and SEBS-g-MA nodules in the PA11 matrix. In the case of functionalized halloysite, the presence of HNTs bundles surrounded with fine SEBS-g-MA nodules is observed. Atomic force microscopy (AFM) also highlighted the different blends morphologies. Incorporation of functionalized halloysite leads to an improvement of the thermal properties without affecting the PA11 crystallization. Moreover, mechanical performance, especially toughness, was highly improved in the presence of functionalized halloysite due to a good stress transfer from the matrix to the modified halloysite agglomerates surrounded by SEBS-g-MA.

Tribological and mechanical properties of polyamide-11/halloysite nanotube nanocomposites

“…As a result, Young's modulus, tensile strength, thermal stability, and fire-retardant properties are often improved. Recently, the Algerian HNTs were successfully tested as a reinforcing agent and a compatibilizer in some polymer blends such as PA11/PS [32], PA11/SEBS-g-MA [33], and PHBV/PBS [34]. On the other hand, on PA11/HNT nanocomposites, there are few publications [1,35,36] and even fewer on the tribological properties.…”

Kinetic and thermodynamic parameters guiding the localization of regioselectively modified kaolin platelets into a PS/PA6 co-continuous blend

“…Its synthesis and characterization were described in a previous work about selective modification of halloysite [35]. PS chains bearing alkoxysilanes functions were used to modify silica and alumina faces of kaolinite particles because these functions are reactive with silanols and aluminols [36]. Two kinds of structure where obtained for the PS chains bearing alkoxysilane groups: a structure with only one trialkoxysilane function at the end of the chain (ETS-PS) and a structure bearing several trialkoxysilane functions along the polymer chain (P(S-co-MPS)).…”

Surface treatment of halloysite nanotubes with sol–gel reaction for the preparation of epoxy composites

“…Surface modications of the external HNT layers were previously achieved by adsorption of cationic polyethyleneimine based polymers onto the negatively charged external surface of HNTs. 18,19 In addition, a silanol amine 20 or ionic liquids were used for the surface modication of HNTs. 21 On the internal surfaces of HNT, Al-OH groups with high chemical activity react with 3-aminopropyltriethoxysilane to form a 3-aminopropyl layer during a sol-gel process.…”