Polymer nanocomposites processing

Koo, J. (2006) Polymer Nanocomposites Processing, Characterization, and Applications. McGraw-Hill, ISBN 0071458212,9780071458214, New York Koval chuk, A. Shevchenko, V. Shchegolikhin, A. Nedorezoca, P. Klyamkina, A. Aladyshev, A. (2008) Effect of carbon nanotube functionalization on the structural and mechanical properties of polypropylene/MWCNT composites. Macromol. Vol.41, No.20, pp.7536-7542... 

J.H. Koo, Polymer Nanocomposites-Processing, Characterization and Applications, McGraw-Hill, New York, pp. 235-261, 2006. 

C. Jayesh, S. Raghunandan, and K.K. Kar, Chapter 19. In J.K. Pandey et al, eds.. Handbook of Polymer Nanocomposites. Processing, Performance and Applications-Volume B Carbon Nanotube based Polymer Composites. 2015, Springer-Verlag Berlin, Germany. 

Koo, J. H. 2006. Polymer Nanocomposites Processing, Characterization, and Applications. New York McGraw Hill Nanoscience and Technology Series. 

Abstract Polymer nanocomposites processing requires incorporating nanoparticles into polymer matrix in a controllable fashion in order to successfully transfer the outstanding properties of nanoparticles to the final nanocomposite. This chapter first reviews various processing techniques to fabricate nanoparticles reinforced polymer nanocomposites. It then discusses some critical processing-related issues for property improvement, including the selection of nanoparticle and polymer matrix, quality of dispersion, ahgnment and functionahzation of nanoparticles. 

Key words polymer nanocomposites processing, carbon nanoparticles,... 

Dalmas F, Chazeau L, Gauthier C, Masenelli-Varlot K, Dendievel R, Cavaille J Y and Forrb L (2005) Multiwalled carbon nanotube/polymer nanocomposites Processing and properties, J Polym Sci Part B Polym Phys Ed 43 1186-1197. 

JOSEPH H. KOO Polymer Nanocomposites Processing, Characterization and Applications NICOLAE O. LOBONTIU Mechanical Design of Microresonators Modeling and Applications... 

Koo JH (2009) Polymer nanocomposites, processing, characterization and applications. Chap. 2. An overview of nanoparticles. McGraw-Hill, New York... 

Dalmas, F., et al. Multiwalled earbon nanotube/polymer nanocomposites processing and... 

Koo J. Polymer nanocomposites processing, characterization, and apphcations. Isted. New York McGraw-Hill 2006. 

In situ polymerization is generally a highly suitable method for the ob-tention of LDH/polymer nanocomposites. Various monomers can be intercalated and polymerized within the interlamellar space of LDH and this spatial confinement is believed to increase the degree of polymerization. Yet, the process is limited by two factors [43] ... 

Davis RD, Bur AJ, McBearty M et al. (2004) Dielectric spectroscopy during extrusion processing of polymer nanocomposites a high-throughput processing/characterization method to measure layered silicate content and exfoliation. Polymer 45 6487-6493... 

The dynamic mechanical thermal analyzer (DMTA) is an important tool for studying the structure-property relationships in polymer nanocomposites. DMTA essentially probes the relaxations in polymers, thereby providing a method to understand the mechanical behavior and the molecular structure of these materials under various conditions of stress and temperature. The dynamics of polymer chain relaxation or molecular mobility of polymer main chains and side chains is one of the factors that determine the viscoelastic properties of polymeric macromolecules. The temperature dependence of molecular mobility is characterized by different transitions in which a certain mode of chain motion occurs. A reduction of the tan 8 peak height, a shift of the peak position to higher temperatures, an extra hump or peak in the tan 8 curve above the glass transition temperature (Tg), and a relatively high value of the storage modulus often are reported in support of the dispersion process of the layered silicate. 

CNT nanocomposites morphological and structural analysis is often done by TEM but an extensive imaging is required then to ensure a representative view of the material. Moreover, carbon based fillers have very low TEM contrast when embedded in a polymer matrix. The application of microscopy techniques is very useful to control the status of CNTs at any time during the preparation process of CNT/polymer nanocomposites, and moreover, to gain insights on parameters important for a better understanding the performance of the final nanocomposite material based on CNTs. 

The properties of polymer nanocomposites are influenced by numerous factors including nanofillers type, purity, and the match between clay and CNT dimensions (length and diameter). These factors should be taken into account in the preparation of polymer nanocomposite, as well as in process of reporting and interpreting the experimental data. 

Fabrication methods have overwhelmingly focused on improving nanotube dispersion because better nanotube dispersion in polyurethane matrix has been found to improve the properties of the nanocomposites. The dispersion extent of CNTs in the polyurethane matrix plays an important role in the properties of the polymer nanocomposites. Similar to the case of nanotube/solvent suspensions, pristine nanotubes have not yet been shown to be soluble in polymers, illustrating the extreme difficulty of overcoming the inherent thermodynamic drive of nanotubes to bundle. Therefore, CNTs need to be surface modified before the composite fabrication process to improve the load transfer from the polyurethane matrix to the nanotubes. Usually, the polyurethane/CNT nanocomposites can be fabricated by using four techniques melt-mixing (15), solution casting (16-18), in-situ polymerization (19-21), and sol gel process (22). 

Among the applications discussed in this chapter, the most prominent in recent years is CNT-reinforced polymer nanocomposites. The use of CNTs in polymers can provide superior mechanical properties (60). For instance, the addition of 1% CNTs might increase the stiffness of polymers by 10% and increase their resistance to fracture however, improvements in the properties of CNT-reinforced polymers largely depend on the dispersion of CNTs within the polymer matrix and the polymer-CNT interfacial properties. The following section highlights several studies regarding the processing of PLA-CNT nanocomposites. 

This chapter is an overview of the synthesis and properties of PVA/ nanotube composites. Various films and fibers have been processed from carbon nanotube and PVA dispersions. Compared to other polymers, PVA exhibit particularly strong interaction with single-walled as well as multiwalled carbon nanotubes. This leads to unique properties which are not observed in other nanotube polymer nanocomposites. In particular, this literature review confirms... 

In the last ten years, a great deal of experimental work has been presented about the tensile properties of CNTs/polymer composites in the literature. However, it is difficult to generalize across these studies because of the large number of parameters that can influence the effective properties, including size and structure of the CNT, CNT/ polymer interaction, processing techniques and processing conditions. In this chapter, the effect of structure and morphology on the properties of the nanocomposites will be focused and discussed. 

Recent developments in the cross-polymerization of the organic components used in bicontinuous microemulsions ensure the successful formation of transparent nanostruc-tured materials. Current research into using polymerizable bicontinuous microemulsions as a one-pot process for producing functional membranes and inorganic/polymer nanocomposites is highlighted with examples. 

A dispersion of nanoparticles of Au or other metals in a polymer matrix may also be obtained by a one-pot process of microemulsion polymerization. For instance, the UV-polymerization of a microemulsion of 35 wt% MMA, 35 wt% AUDMAA and 30 wt% of 0.1 M HAUCI4 aqueous solution would produce a Au-polymer nanocomposite, as shown in Fig. 12 [104]. This TEM micrograph shows a microtoned thin film of the sample. It is clearly apparent that Au particles of about 10-15 nm are well dispersed in the polymer matrix. 

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