Effect of molecular structures on static and dynamic compression properties of clay and amphiphilic clay/carbon nanofibers used as fillers in UHMWPE/composites for high‐energy‐impact loading

Abstract

Three different ultrahigh‐molecular‐weight polyethylene (UHMWPE)–clay nanocomposites (Muscovite, Cloisite 30B and amphiphilic clay/carbon nanofibers) were investigated with the nanocomposite nanomorphology studied before and after dynamic mechanical compressive tests at high strain rates. Their material structure and thermal properties were investigated using techniques such as step‐scan differential scanning calorimetry, split Hopkinson pressure bar, synchrotron small angle X‐ray scattering (SAXS), and dynamic mechanical analysis. Results were associated with morphological changes observed after deformation. chemical vapor deposition (CVD)‐modified nanocomposite, due to the molecular bonding and the extra functional groups, is designed with crystalline structures with fewer defects and higher stability. The increase in particulate/polymer interactions observed for the CVD‐modified material decreased the elongation in the quasi‐static test. However, the dynamic mechanical behavior contradicted the quasi‐static behavior because at very high strain rates there was not sufficient time for the interlamellar and intralamellar defect facilitated plastic flow and the material transitioned through the glassy state. The SAXS results show that deformation strongly induced changes in the UHMWPE and UHMWPE–clay nanocomposite morphology. SAXS indicates that CVD‐modified samples became more compact and dense, thus corroborating the formation of additional secondary bonds between structures and/or the carbon nanofibers alignment. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47094.

Investigation of thermal and mechanical properties of polybenzoxazine obtained in an in situ polymerization with surface‐modified montmorillonite clay

“…Because of the versatile properties of clay, it also attracts many researchers and is used as filler in the preparation of composites. [12] Recently, the clay minerals were successfully loaded into the polymeric matrix after modifying the surface of clay with suitable linkers, which eliminate the compatibility issues. Naturally available clays such as kaolinite, vermiculite, montmorillonite (MMT) and pyrophyllite are widely used as catalysts for many organic reactions and transformations, namely dimerization, dehydration, isomerization, Friedel Crafts reactions, several photochemical reactions, and so forth.…”

High‐strain‐rate mechanical performance of particle‐ and fiber‐reinforced polymer composites measured with split Hopkinson bar: A review

“…Compressive strength, at different filler weight contents and strain rates of PP/S, [112] PP/ZnO, [57] E/S, [113] E/ GO, [114] E/CNT, [115] PE/GNP, [116] PE/C, [117] E/PS, [118] and PE/SD. [119] C, clay; E, epoxy; GO, graphene oxide; GNP, graphene nanoplatelets; PE, polyethylene; PP, polypropylene; PS, polystyrene microspheres; S, silica; SD, sawdust; ZnO, zinc oxide F I G U R E 1 4 Compressive modulus (measured at a strain rate of 10 3 s À1 ), at different filler weight content of PP/S, [112] PP/ ZnO, [57] E/GO, [114] PE/C, [117] E/PS, [118] and PE/SD, [119] and E/GNP.…”

“…Compressive strength, at different filler weight contents and strain rates of PP/S, [112] PP/ZnO, [57] E/S, [113] E/ GO, [114] E/CNT, [115] PE/GNP, [116] PE/C, [117] E/PS, [118] and PE/SD. [119] C, clay; E, epoxy; GO, graphene oxide; GNP, graphene nanoplatelets; PE, polyethylene; PP, polypropylene; PS, polystyrene microspheres; S, silica; SD, sawdust; ZnO, zinc oxide F I G U R E 1 4 Compressive modulus (measured at a strain rate of 10 3 s À1 ), at different filler weight content of PP/S, [112] PP/ ZnO, [57] E/GO, [114] PE/C, [117] E/PS, [118] and PE/SD, [119] and E/GNP. [120] C, clay; E, epoxy; GO, graphene oxide; GNP, graphene nanoplatelets; PE, polyethylene; PP, polypropylene; PS, polystyrene microspheres; S, silica; SD, sawdust; ZnO, zinc oxide the strength of the particle-matrix interfacial bonding strength is more important than the quality of the particle dispersion, in terms of an enhancement in mechanical properties.…”

Combined effect of montmorillonite Cloisite 30B and graphene nanoplatelets on high‐density polyethylene matrix under high strain rate dynamic compression

“…5 Therefore, adding compatibilizing agents (CAs) such as maleic anhydride (MA), which act on the interface between organic and inorganic surfaces, is an option to increase adhesion between materials, especially in cases of polar to non-polar substances. 6 Dias et al 7 showed that the incorporation of clay montmorillonite Cloisite 30B in the molten state in an ultra-high density polyethylene matrix, without the use of a CA, resulted in reduced mechanical and dynamic mechanical properties, if compared to those found for the pure polymer. On the other hand, an increase in the filler-matrix adhesion and the consequent improvement in the mechanical properties of the polyethylene and bentonite clay maleinized composite was observed.…”

“…Although substantial changes can be realized with small amounts of Gr (<3 wt.%), 11,13,17 such as increased impact resistance and energy absorption capacity, clays are usually used at 1 to 5 wt.%. 4,7,9,10 For this reason, this work aims to evaluate the effect of the combination of montmorillonite Cloisite 30B organically modified montmorillonite (OMt) (0, 1, 3, and 5 wt.%) and GNP (ranged from 0 to 50 wt.% of the OMt content) in maleinized highdensity polyethylene (HDPE) matrix on the properties obtained from the SHPB dynamic compression test.…”