Nanocomposites from organoclay

F. Chavarria, K. Nairn, P. White, A. J. Hill, D. L. Hunter, and D. R. Paul. Morphology and properties of nanocomposites from organoclays with reduced cation exchange capacity. Journal of Applied Polymer Science, 105 (2007), 2910-2924. 

Very few papers have been published on the preparation of polymer blend nanocomposite from organoclays and poly(ethylene oxide)/poly(methyl methacrylate) (PEO/PMMA) blend by the solution blending method." In this section, we discuss how the blending sequence affects the microstructure of the ternary hybrid nanocomposites and especially the dispersion states of the organoclays in the polymer matrix. 

FIGURE 28.16 Storage modulus vs temperature of organoclay-loaded rubber nanocomposite. (From Teh, P.L. et al., J. Appl. Polym. Sci., 100, 1083, 2006.)... 

Polyimide-clay nanocomposites constitute another example of the synthesis of nanocomposite from polymer solution [70-76]. Polyimide-clay nanocomposite films were produced via polymerization of 4,4 -diaminodiphenyl ether and pyromellitic dianhydride in dimethylacetamide (DMAC) solvent, followed by mixing of the poly(amic acid) solution with organoclay dispersed in DMAC. Synthetic mica and MMT produced primarily exfoliated nanocomposites, while saponite and hectorite led to only monolayer intercalation in the clay galleries [71]. Dramatic improvements in barrier properties, thermal stability, and modulus were observed for these nanocomposites. Polyimide-clay nanocomposites containing only a small fraction of clay exhibited a several-fold reduction in the... 

Zhu, L. and Wool, R.P. (2005) Acrylate mbber/organoclay hybrid nanocomposites from renewable resources. Proceedings of the American Society for Composites, Technical Conference, 2005 20th, 148/1-/18. 

Two fimdamental aspects of the organoclay determine the formation of epoxy nanocomposites from in-situ polymerization the abUity of the interlayer exchanged ion to act as a compatibUizer and render the layered silicate epoxyphilic , and the catalyzing effect of the exchanged ion on the polymerization reaction in the galleries [31]. 

The quantity of the hterature in the field of the nanocomposite polymeric materials has grown multiple times in recent years. The possibility to use almost all polymeric and polycondensated materials as a matrix is shown The nanocomposites from various organoclays and polymers have been synthesized. Here is just a small part of the compounds for being the matrix referenced in literature polyacrylate [83], polyamides [82,84,85], polybenzoxazine [86], polybutylene terephtalate [11,82,87], polyimides [88], polycarbonate [89], polymethylmetaciylate [90], polypropylene [91,92], poly-... 

Y. Lu and R. C. Larock, Bio-based nanocomposites from corn oil and functionalized organoclay prepared by cationic polymerization , Macromol Mater Eng, 2007,292,863-72. 

Filippi, S., Marazzato, C., Magagnini, R, Minkova, L., Tzankova Dintcheva, N., and La Mantia, F. P. 2006. Organoclay nanocomposites from ethylene-acrylic acid copolymers. Macromolecular Materials and Engineering 291 1208-1225. 

Nanocomposites can be formed from organoclays, in situ solution, and emulsion polymerization. The melt processing is of increased interest. Clays that are exfoliated are completely separated by polymers between them. This desired morphology is achieved to varying degrees in practice. 

TEM photomicrographs of nanocomposites prepared from organoclay containing two long alkyl tails, M2(HT)2 dimethyl bis (hydrogenated tallow) and LDPE (A), ethylene/methacrylic acid copolymer containing 3.9 wt% methacrylic acid (EMAA-1) (B), and ethylene/methacrylic acid copolymer containing 8.9 wt% methacrylic acid (EMAA-2) (C). The concentration of MMT in all cases is 2.5 wt%. (From R. K. Shah, D. H. Kim, and D. R. Paul, Polymer 48,1047-1057,2007. With permission.)... 

As it is known [4], the parameter x influences essentially on nanocomposites polymer/organoclay properties. One from the most important mechanical characteristics of polymeric materials, namely, elasticity modulus E depends on the value as follows ... 

The Equation (14) and Equation (18) describe theoretically the experimental dependences of nanocomposites polymer/organoclay combustibility on nanofiller stmc-ture. So, organoclay contents cp increasing results in X reduction and, respectively, in Q decrease. The transition from organoclay exfoliated stracture up to intercalated one results in a packet (tactoid) from N organoclay platelets formation, that increases... 

Thermal stability of polystyrene nanocomposites from improved thermally stable organoclays... 

Polystyrene/clay nanocomposites from thermally stable organoclays 71... 

Polystyrene/clay nanocomposites from polymer/oligomer modified organoclays... 

R. K. Shah, L. Cui, K. L. Williams, B. Bauman, and D. R. Paul. Nanocomposites from fluoro-oxygenated polyethylene a novel route to organoclay exfoliation. Journal of Applied Polymer Science, 102 (2006), 2980-2989. 

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