Performant Clay/Carbon Nanotube Polymer Nanocomposites

Abstract

This contribution aims at reviewing on very recent developments in syntheses, properties and (future) applications of polymer‐based nanocomposites filled with either organoclays and/or carbon nanotubes. Undoubtedly, the key‐challenge remains to reach a high level of nanoparticle dissociation (i.e., either to delaminate the silicate nanoplatelets or to break down the bundles of aggregated carbon nanotubes) and their fine dispersion upon melt blending within the selected polymer matrix. In that context, the in situ polymerization/grafting process as catalyzed directly from the nanofiller (organoclay or carbon nanotube) surface proved highly efficient allowing for the complete destructuration of the native filler aggregates. Dissociated nanoparticles were accordingly recovered, their surface was homogeneously coated/grafted by the in situ grown polymer chains as generated by this so‐called “Polymerization‐filling technique” (PFT). Interestingly enough, such surface‐coated organoclays and/or carbon nanotubes were further added as “masterbatch” in commercial polymeric matrices by twin‐screw extrusion. As a result of the pre‐destructuration of the nanofillers by PFT, it comes out that the resulting polymer nanocomposites displayed much higher thermo‐mechanical properties even with a nanofiller loading as tiny as 1wt%.

Polymer/Carbon Nanotube Nanocomposites

“…To disperse the nanotube in non-polar polymer matrices, such as polyolefins, polymerization-filling technique (PFT) was used. In this process nanotube is first dispersed with catalyst and cocatalyst and followed by polymerization (Dubois & Alexandre, 2006). This technique leads to individualization of nanotube and allows the homogeneous dispersion of nanotubes upon melt blending.…”

“…An approach developed by Jin et al (2002) introduces polymer-coated MWCNT (rather than pristine MWCNT) into the polymer melt to promote compatibilization. However optimization of processing conditions is an important issue, not just for different nanotube types, but for the whole range of polymer-nanotube combinations (Dubois & Alexandre, 2006). iii.…”

Synergistic effects of Na+-montmorillonite and multi-walled carbon nanotubes on mechanical properties of chitosan film

“…The preparation of nanocomposites based on CNTs is one of the hot topics in the CNTs field [9,10] because of their unique properties such as high modulus, high intrinsic electrical conductivity, small size and high thermal conductivity [11,12]. CNTs have been proved to be advanced multi-functional fillers in polymer-based nanocomposites [13,14]. IR photoresponse of CNTs is dramatically enhanced by embedding CNTs into the polycarbonate matrix [15].…”

Comparação entre Nanocompósitos de Polietileno/Nanotubos de Carbono e Polietileno/Nanolâminas de Grafeno Obtidos por Polimerização In Situ

“…Este processo original, chamado de técnica de polimerização de enchimento (TPE) foi inicialmente investigado na polimerização in situ utilizando catalisadores Ziegler-Natta [17] . A partir disso, o método foi estendido para os catalisadores metalocênicos e consiste, primeiramente, em ancorar metilaluminoxano (MAO), o cocatalisador, na superfície dos NTCs [1,[17][18][19][20][21][22] . Outros autores tem ligado diretamente o catalisador metalocênico diretamente ao suporte de NTCPMs, previamente oxidado, de maneira a ligar o catalisador aos grupos funcionais-COOH ou -OH criados nos NTCs durante a oxidação [23,24] .…”

“…Outros autores tem ligado diretamente o catalisador metalocênico diretamente ao suporte de NTCPMs, previamente oxidado, de maneira a ligar o catalisador aos grupos funcionais-COOH ou -OH criados nos NTCs durante a oxidação [23,24] . A adição de monômero olefínico leva à síntese de cadeias poliméricas exclusivamente localizadas nos arredores da superfície do NTC que, com o aumento de massas moleculares, precipita-se sobre os nanotubos, cobrindo-os e levando a uma eficiente desaglomeração [1,17,22] . Nos últimos anos nosso grupo de pesquisa vem trabalhando na obtenção de nanolâminas de grafeno (NG) (empilhamento de poucos grafenos) através de esfoliação química e térmica da grafite e na preparação de nanocompósitos de polietileno (PE) [25,26] e de polipropileno (PP) [27][28][29] utilizando a técnica de polimerização in situ.…”