Nanoclay composite

This is a nonpolar rubber with very little unsamration. Nanoclays as well as nanotubes have been used to prepare nanocomposites of ethylene-propylene-diene monomer (EPDM) rubber. The work mostly covers the preparation and characterization of these nanocomposites. Different processing conditions, morphology, and mechanical properties have been smdied [61-64]. Acharya et al. [61] have prepared and characterized the EPDM-based organo-nanoclay composites by X-ray diffracto-gram (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy... 

Nanoparticles can increase water absorption by WPCs. For example, after a month of underwater exposnre of the WPC (50% polypropylene -l- nanoclay, w/w, 46% maple wood flour [80-mesh], and 4% conpling agent) no-nanoclay composite absorbed 2.7% of water, 4%-nanoclay composite absorbed 2.9% of water, and 10%-nanoclay composite absorbed 4.4% water [24], It also makes nanoparticles undesirable in WPC prodncts, nnless some means are found to overcome this problem. 

In nanoclay composites, particularly from montmoril-lonite, the shape and dimensions of platelets after extrusion process were observed using TEM and wet-STEM. The differences in the size observed between platelets using TEM and STEM techniques were attributed to the preparation by ultramicrotomy and the effect of projection [72]. Thus, in this case, the combination of microscopy techniques revealed the effect of each step of the process. 

Tong ZH, Deng YL (2006) Synthesis of water-based polystyrene-nanoclay composite suspension via miniemulsion polymerization. Ind Eng Chem Res 45 2641-2645... 

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

Wan Wang, L., Wang, K., Chen, L., Zhang, Y.-W., He, C.-B. Preparation, morphology and thermal/ mechanical properties of epoxy/nanoclay composite. Composites Part A - Appl. Sci. Manufacturing 37 (2006) 1890-1896. 

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... 

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. 

Published items in the field of (a) nanoclay composite and (b) needle-like clay composites, according to Web of Science, updated to end of 2009. The search criteria are indicated in each graph. 

The good solvent resistance of polyolefins has effectively prevented the use of solution processing as a viable and industrially acceptable preparation method for nanoclay composites. Polyolefin/nanoclay composites have been almost exclusively prepared via melt compounding, with few cases of in situ polymerization. In the following sections, these preparation methods are analyzed in more detail. 

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

Some proteins were studied for a long time for their materials applications soy protein/ wheat gluten and collagen (the denatured form being called gelatine). In all the cases, the stahilily of the proteins and their sensitivity to moisture require strengthening by plasticization, com-patibilization, cross-linkage or production of protein-nanoclay composites. ... 

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]. 

Bae, H.J., Darby, D.O., Kimmel, R.M., Park, H.J., and Whiteside, W.S. 2009. Effects of transglutaminase-induced cross-linking on properties of fish gelatin-nanoclay composite film. Food Chem. 114 180-189. 

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. 

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]. 

XRD pattern of pure nanoclay, neat, 1 and 2 wt% epoxy nanoclay composites. 

Figure 63 (a) X-ray diffraction patterns of organically modified Closite-30B nanoclay and nanocomposites, (b) small-angle neutron scattering patterns I(q) versus q (wave vector) plot of indicated PU and nanocomposites, (c, c ) AFM image of PU and its nanocomposites with height profile, and (d) POM image PU-nanoclay composite [9]. 

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. 

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. 

Several experiments have been reported in the literature involving rubber-nanoclay composites, with the observation of improved mechanical and thermal properties. The addition of small amounts of the nanoclay greatly improved the thermal stability and swelling behaviour, which was attributed to the good barrier properties of the dispersed and partially exfoliated organo clay particles. ... 

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... 

In the extrusion of PA6/nanoclay composite films, a 4% nanoclay masterbatch prepared in a twin screw compounding extruder was combined in a 50 50 blend with the natural PA6 using the chaotic mixer. Permeability calculations indicated that closing pathways around platelets resulted in values approaching zero [38]. 

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