Fabrication techniques polymer nanocomposites

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). 

To fabricate different polymer layers in a device using solution based techniques, mutually exclusive solvents have to be identified, which is often very difficult. CVD eliminates these difficulties and excellent heterojunctions and multilayered films can be fabricated relatively easily. Also, the capability to co-deposit compounds can be achieved. This ease of co-depositing compounds has enabled the synthesis of several inorganic-organic hybrids, which can also be tailored as nanocomposites at the molecular level. 

PPy nanocomposites have been extensively reported in the literatme [261-267]. In the case of inorganic nanoparticles/conducting polymer nanocomposites, various inorganic nanomaterials including silica, palladium, platinum, and maghemite have been formed via inclusion techniques using both chemical and electrochemical approaches [261]. Multifunctional nanocomposites could be fabricated by the judicious choice of synthetic techniques and inorganic materials. 

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. 

With the objective of a successful and economical recycling process in which the recycled polymer has largely acceptable properties, considerable effort must be made to encompass all the aspects of recycling in future studies to enhance the competitiveness of these systems. The first step could be the improvement of interfacial adhesion in prepared nanocomposites to achieve better physical and mechanical properties from recycled polymer wastes. Many procedures such as compatibilisation, functionalisation and surface modification could be developed in the future. Furthermore, the addition of effective nanofillers including available nanofillers or a combination of nanofillers will provide further progress and new opportunities in these systems. In addition, the development of fabrication techniques and also, the optimisation of available methods such as melt mixing should be performed, due to its important role in the final properties of recycled products. 

One of major changes for high performance polymer nanocomposites is to optimize the processing of CNT-reinforced polymer nanocomposites with low costs. Four processing techniques are in common use to fabricate the CNT/polymer nanocomposites direct mixing, solution method, in situ polymerization, and melt compounding [26-35]. Among these... 

This chapter aims to review the developments of biobased polymer/clay nanocomposites comprising general fabrication techniques and optimization of mixture homogeneity in solutions. Furfliermore, the effects of interactions between biopolymer matrices and nanoclays on structural, mechanical, and thermal properties, and biode-gradabUity of currently available biobased polymer nanocomposites are reviewed. Finally, future trends are also summarized for such nanocomposites with great enhancements of mechanical, thermal, and biodegradable properties. 

In Part Two, Chapter 4 describes a general fabrication-characterization route of electrospinning PLA poly(s-caprolactone) (PCL)/HNT composite fibers. The effects of HNTs with or without the modifier 3-aminopropyltriethoxysilane on fiber diameter, morphological structure, thermal properties, crystalline stmctures, and degree of crys-talhnity, as well as the intermolecular interaction of electrospun nanocomposite fibers, are thoroughly studied to provide the appropriate guidance to the controlled drug release associated with fibrous structures. Chapter 5 deals with the synthesis and characterization of CNT hybrid fillers via chemical vapor deposition (CVD) technique for polymer nanocomposites. Optimized synthesis parameters are presented and comparative studies are also conducted between chemical hybrid-filled and physical hybrid-fiUed polymer nanocomposites in terms of their typical applications. 

Two different lithographic techniques have been employed for fabrication of polymer-based nanocomposites ... 

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