Thermoplastic nanocomposite morphology

Mehta, S., Mirabella, F. M., Rufener, K., and Bafna, A. 2004. Thermoplastic olefin/clay nanocomposites Morphology and mechanical properties. Journal of Applied Polymer Science 92 928-936. 

Lu Y, Weng L, Cao X (2005) Biocomposites of plasticized starch reinforced with cellulose crystallites fromcottonseed linter. Macromol Biosci 5 1101-1107 Lu Y, Weng L, Cao X (2006) Morphological, thermal and mechanical properties of ramie crystallites-reinforced plasticized starch biocomposites. Carbohydr Polym 63 198-204 Malainine ME, Mahrouz M, Dufi esne A (2005) Thermoplastic nanocomposites based on cellulose microfibrils from Opuntia ficus-indica parenchyma cell. Compos Sci Technol 65 1520-1526 Mangalam AP, Simonsen J, Benight AS (2009) Cellulose/DNA hybrid nanomaterials. Biomacromolecules 10 497-504... 

The use of a commercial Cloisite 20A organoclay to prepare SBS-based nanocomposites by melt processing was recently reported [63]. In this case, the nanocomposite morphology was characterized by a combination of intercalated and partly exfoliated clay platelets, with occasional clay aggregates present at higher clay content. For this particular thermoplastic elastomer nanocomposite system, well-dispersed nanoclays lead to enhanced stiffness and ductility, suggesting promising improvements in nanocomposite creep performance. The use of stearic acid as a surface modifier of montmorillonite clay to effectively improve the clay dispersion in the SBS matrix and the mechanical properties of the SBS-clay nanocomposites was reported [64]. 

Koemer H, Kelley J, George J, Drummy L, Mirau P, Bell NS, Hsu JWP, Vaia RA (2009) ZnO nanorod-thermoplastic polyurethane nanocomposites morphology and shape memory performance. Macromolecules 42 8933-8942... 

The reinforcement of polypropylene and other thermoplastics with inorganic particles such as talc and glass is a common method of material property enhancement. Polymer clay nanocomposites extend this strategy to the nanoscale. The anisometric shape and approximately 1 nm width of the clay platelets dramatically increase the amount of interfacial contact between the clay and the polymer matrix. Thus the clay surface can mediate changes in matrix polymer conformation, crystal structure, and crystal morphology through interfacial mechanisms that are absent in classical polymer composite materials. For these reasons, it is believed that nanocomposite materials with the clay platelets dispersed as isolated, exfoliated platelets are optimal for end-use properties. 

Asi Asif, A., Rao, V. L., Saseendran, V., Ninan, K. N. Thermoplastic toughened layered silicate epoxy ternary nanocomposites - Preparation, morphology, and thermomechanical properties. Polym. Eng. Sci. 49 (2009) 756-767. 

Ale Alessi, S., Conduruta, D., Pitarresi, G., Dispenza, C., Spadaro, G. Accelerated ageing due to moisture absorption of thermally cured epoxy resin/polyethersulphone blends Thermal, mechanical and morphological behaviour. Polym. Degradation Stability 96 (2011) 642-648. llAsi Asif, A., Rao, V. L., Ninan, K. N. Preparation, characterization, thermo-mechanical, and barrier properties of exfoliated thermoplastic toughened epoxy clay ternary nanocomposites. Polym. Adv. Technol. 22 (2011) 437 47. 

In this article, recent developments in the formation and properties of epoxy layered silicate nanocomposites are reviewed. The effect of processing conditions on cure chemistry and morphology is examined, and their relationship to a broad range of material properties elucidated. An understanding of the intercalation mechanism and subsequent influences on nanocomposite formation is emphasized. Recent work involving the structure and properties of ternary, thermosetting nanocomposite systems which incorporate resin, layered silicates and an additional phase (fibre, thermoplastic or rubber) are also discussed, and future research directions in this highly active area are canvassed. 

This chapter reviews the general context of starch as a material. After a survey of the major sources of starch and their characteristic compositions in terms of amylase and amylopectin, the morphology of the granules and the techniques applied to disrupt them are critically examined. The use of starch for the production of polymeric materials covers the bulk of the chapter, including the major aspect of starch plasticization, the preparation and assessment of blends, the processing of thermoplastic starch (TPS), the problems associated with its degradation and the preparation of TPS composites and nanocomposites. The present and perspective applications of these biodegradable materials and the problems associated with their moisture sensitivity conclude this manuscript. 

Nanocomposite technology using small amounts of silicate layers can lead to improved properties of thermoplastic elastomers with or without conventional fillers such as carbon black, talc, etc. Mallick et al. [305] investigated the effect of EPR-g-M A, nanoclay and a combination of the two on phase morphology and the properties of (70/30w/w) nylon 6/EPR blends prepared by the melt-processing technique. They found that the number average domain diameter (Dn) of the dispersed EPR phase in the blend decreased in the presence of EPR-g-MA and clay. This observation indicated that nanoclay could be used as an effective compatibilizer in nylon 6/EPR blend. X-ray diffraction study and TEM analysis of the blend/clay nanocomposites revealed the delaminated clay morphology and preferential location of the exfoliated clay platelets in nylon 6 phase. 

Wahit, M. U., Hassan, A., Mohd Ishak, Z. A., Rahmat, A. R., and Abu Bakar, A. 2006. Morphology, thermal, and mechanical behavior of ethylene octene copolymer toughened polyamide 6/poly-propylene nanocomposites. Journal of Thermoplastic Composite Materials 19 545-567. 

Koemer H, Liu W, Alexander M, Mirau P, Vaia RA, et al. Deformation-morphology correlations in electrically conductive carbon nanotube—thermoplastic polyurethane nanocomposites. Polym J March 2005 46 4405-20. 

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