Effect of kaolinite on the properties and structure of PTFE

Multiscale analysis and experimental validation of the effective elastic modulus of epoxy-dioctahedral phyllosilicate clay composite

“…From the studies mentioned in the preceding paragraph, it is obvious that kaolinite is a suitable choice of reinforcement for PMCs, most especially in little quantity. However, most researchers concentrated on modified kaolinite/nano-sized kaolinite inclusions as their choice of reinforcement in PMCs and this explicitly clarifies why there has been a dwindling interest in raw micro-sized kaolinite as reinforcements in PMCs [8,9,10,11,12]. In addition, previous findings have shown the limitations of raw kaolinite as reinforcement in PMCs due to some of its unappealing intrinsic properties such as absence of intercalated charge-balancing cations and linkage of its adjacent layers by hydrogen bonds.…”

“…Introduction of 2-10 wt. % annealed kaolinite particles into polytetrafluoroethylene (PTFE) matrix also resulted in favourable increase in the wear resistance of the PTFE-kaolinite composites [12]. Similarly, de Mac edo Neto et al [13] successfully improved the wear resistance of polystyrene nanocomposites reinforced with 1-3 wt.…”

“…The micromechanical models used for verification are stated in Eqs. ( 7), ( 8), ( 9), ( 10), (11), (12), and (13) [19].…”

“…Attempts made by researchers to eliminate these drawbacks include mechanical, thermal, chemical and thermochemical modifications of kaolinite particles prior to or during their deployment in PMCs, however the associated rise in cost and reduced eco-integrity of the resultant composites cannot be pushed aside [8,9,10,11,12]. As a result of this, adoption of cost-effective, fast and dependable numerical frameworks for virtual characterization of new materials began to gain significant attention.…”

“…6 wt.% was chosen as the preferable volume fraction for kaolinite as previous findings have shown it is apparently the critical filler content beyond which elastic modulus of polymer-kaolinite composites begins to drop [8,11]. This has been attributed to the high tendency of raw kaolinite particles to agglomerate at this filler content unless they are subjected to surface modification [8,11,12].…”