Polymer-nanoclay composites

Hazarika A, Maji TK (2014c) Strain sensing behavior and dynamic mechanical properties of carbon nanotubes/nanoclay reinforced wood polymCT nanocomposite. Chem Eng J 247 33-41 Hazarika A, Maji TK (2014d) Thermal decomposition kinetics, flammability, and mechanical property smdy of wood polymtar nanocomposite. J Therm Anal Calorim 115 1679-1691 Hazarika A, Mandal M, Maji TK (2014) Dynamic mechanical analysis, biodegradability and thermal stability of wood polymer nanocomposites. Compos Part B 60 568-576 Hetzer M, Kee D (2008) Wootl/polymer/nanoclay composites, environmentally friendly sustainable technology a review. Chem Eng Res Des 86 1083-1093 Hill CAS, Abdirl KHPS, Hale MD (1998) A study of the potential of acetylation to improve the properties of plant fibres, frrd Crops Prod 8 53-63 Hoffmann MR, Martin ST, Choi WY, Bahnemann W (1995) Environmental application of semiconductm photocatalysis. Chem Rev 95 69-96 Huda MS, Drzal LT, Misra M, Mohanty AK (2(K)6) Wood-fiber-reinforced poly(lactic acid) composites evaluation of the physicomechanical and morphological properties. J AppI Polym Sci 102 4856-4869... 

Development of new, biodegradable, polymeric materials. The precise formulation of the LDH with catalytically active metal cations might permit their role as biocatalysts to favour degradation of the polymeric component. Polymer-nanoclay composites are currently very actively studied as potential candidates for oxo-biodegradable plastics [166]. 

Galgali, G., Agarwal, S., and Lele, A., Effect of clay orientation on the tensile modulus of polypropylene-nanoclay composites, Polymer, 45, 6059-6069 (2004). 

The relaxation behavior of poly(trimethylene 2,6-naphthalate)/nanoclay composites has been investigated by DSC and dynamic mechanical analysis [81]. The incorporation of two different types of nanoclays in the polymer matrix intercalates the chains in the... 

H.A. Patel, R.S. Somani, H.C. Bajaj, and R.V. Jasra, Nanoclays for polymer nano composites, paints, inks, grccises cuid cosmetics formulations, drug delivery vehicle and waste water treatment. Bull. Mater. Set, 29 (2), 133-145,2006. 

Mani, G., Fan, Q., Ugbolue, S. C., and Yang, Y. 200 Morphological studies of polypropylene-nanoclay composites. Journal of Applied Polymer Science 97 218-226. 

V. Sridhar and D. K. Tripathy, Barrier Properties of Chlorobutyl Nanoclay Composites, Journal of Applied Polymer Science, 2006, 101, 3630. 

Belgian cable company Kabelwerk Eupen has introduced a commercial application for polymer-clay composites to make flame retardant cables. EVA-based cable jackets are combined with the clay materials in what is called a one-pot synthesis extrusion technique. 5% of the nanoclay improves the fire performance of the EVA compound by promoting char formation and delaying degradation. In addition, it prevents dripping of any burning polymer material. 

Balachandran, M., Bhagawan, S. Mechanical, thermal and transport properties of nitrile mbber (NBR)-nanoclay composite. J. Polym. Res. 19, 2-10 (2012)... 

If chemical treatment of the matrix polymer blend or the filler needs to be avoided or the interaction between the components is insufficient, then a third component, such as a polymer compatibilizer [20], can be added to the composite. Compatibilizers are added especially to polyolefin/nanoclay composites prepared by melt blending because the organo modification of the clay is seldom sufficient to create a favorable interaction between polymer chains and the clay sheets [21]. The interfacial adhesion between the compatibilizer and clay galleries is influenced by the functionality and its concentration, molecnlar weight and molecular weight distribution of the compatibilizer, and the mass ratio of the compatibilizer to the clay [22]. 

In 2007, Rezanejad and Kokabi developed a low density polyethylene (LDPE)/ nanoclay composite with shape memory properties [72], Although all SMPs do not necessarily rely on a two-phase structure such as that of melt processed LDPE, extrapolation from this work can be made for a wide range of SMP systems. The team used organically modified Cloisite 15A nanoclay as filler and demonstrated a 300% increase in both E and E" upon addition of up to 8% nanoclay. Although the neat polymer system had nearly 100% shape recovery, the 8% loaded sample recovered nearly 80% at pre-strains of both 50 and 100%. Recovery stress, however, was dramatically increased from 1 MPa for the neat LDPE to about 3 MPa at 50% pre-strain and above 3 MPa at 100% pre-strain. 

Abstract In this chapter, we report the findings of experimental investigations conducted on durability of glass fiber-reinforced polymer (GFRP) composites with and without the addition of montmorillonite nanoclay. First, neat and nanoclay-added epoxy systems were characterized to evaluate the extent of clay platelet exfoliation and dispersion of nanoclay. GFRP composite panels were then fabricated with neat/modified epoxy resin and exposed to six different conditions, i.e. hot-dry/wet, cold-dry/wet, ultraviolet radiation and alternate ultraviolet radiation-condensation. Room temperature condition samples were also used for baseline consideration. 

Apart from these properties, the exeellent barrier eapability to moisture and gases of polymeric nanocomposites has shown significant potential in civil engineering applications [34—36]. It was reported that the construction industry will be one of the major potential consumers of nanostructured materials [37]. A substantial decrease in moisture permeability was reported in polyamide nanoclay composites with water absorption rate reduced by 40% in comparison to neat polymer [38]. An 80% decrease in water absorption was reported for poly (e-caprolactone) nanoclay composites [39]. Hackman and Hollaway studied the potential appheations of clay nanocomposite materials to civil engineering structures. They eoncluded that their ability to increase the service life of materials subjected to aggressive environments could be utilized to increase the durability of glass and carbon fiber composites [34]. 

The decrease in weight gain for the nanophased composites can be attributed to the hybrid exfoliated and intercalated nanoclay platelets in polymer. Nanoclay platelets when exfoliated/dispersed well in the matrix provide the barrier to gas/liquid in a tortuous manner [12]. This can be attributed to the gas/moisture and radiation barrier properties of montmorillonite nanoclay, which is consistent with results reported by Woo et al. [35]. 

Patel RH, Patel KS. Synthesis of flame retardant polyester-urethanes and their applications in nanoclay composites and coatings. Polym Int March 2014 63(3) 529-36. 

Paul and Robeson et al. [139] have published an extremely informative review on the properties of exfoliated nanoclay-based nanocomposites. These have dominated the polymer literature, but there are a large number of other significant areas of current and emerging interest. This review details the technology involved with exfoliated clay-based nanocomposites and also includes other important areas, such as barrier properties, flammability resistance, biomedical applications, electrical/electronic/optoelectronic applications, and fuel cell interests. The important question of the nanoeffect of nanoparticles or fiber inclusion relative to their large-scale counterparts is addressed relative to crystallization and glass transition behavior. Other polymer (and composite)-based properties derive benefits from the nanoscale filler or fiber addition, and fhese questions are addressed. 

Several proteins have been extensively studied for their materials applications. Among them, soy protein is one of the most popular. Indeed, since the early 1930s it was used in phenol-formaldehyde blends for automotive applications. However, soy protein is sensitive to moisture and exhibits relatively low strength properties. Thus stabilization by plasticization, compatibilization or crosslinkage is required to maintain long-term performance of soy protein-based plastic materials. Also, several studies on soy protein-based blends with other natural polymers or their reinforcement by natural fibres have been performed. More recently studies on soy protein-nanoclay composites and polyfbutylene adipate-co-terephthalate) (PBAT) blends were also performed. 

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