Toyota research group

However, the field of polymer day silicate has only started to speed up recently, mixing the appropriate modified layered silicate with synthetic layered silicates has long been known (Theng, 1979). The interest in these materials came from two important findings, first has been reported by Toyota research group of a Nylon-6 (N6)/Na-MMT nano-composites (Okada et ah, 1990) where very small amounts of layered silicate loadings resulted in the improvements of thermal and mechanical properties and second the findings of Vaia et ah (1993) about the... 

The data provided by Toyota Research Group of Japan on polyamide-MMT nanocomposites indicate tensile strength improvements of approximately 40%-50% at 23°C and modulus improvement of about 70% at the same temperature. Heat distortion temperature has been shown to increase from 65°C for the unmodified polyamide to 152°C for the nanoclay-modified material, all the above having been achieved with just a 5% loading of MMT clay. Similar mechanical property improvements were presented for polymethyl methacrylate-clay hybrids [27]. 

Many researchers have shown that incorporation of nanoscale dimension particles (inorganic fillers, nanotubes, nanofibers etc) into a polymer matrix enhances the mechanical properties of the polymer without significantly raising its density or sacrificing its light transmission property. For instance, the Toyota research groups... 

Clay-polymer nanocomposites, a new class of hybrids, came into the purview of researchers after their invention by the Toyota research group [7,8]. They found dramatic improvement in tensile properties of polymers by adding clay in small weight fractions. In continuation of this, other researchers have used various techniques to develop polymer nanocomposites with clay as reinforcement after proper organic treatment. 

Depending on the distribution of micro/nanofiller in the polymer matrix, the composites may be classified as microcomposites or nanocomposites. These two types of composites differ significantly with respect to their properties. The nanocomposites show improved properties compared to pure polymer or that of microcomposites. It started only back in 1990, when Toyota research group showed that the use of montmorillonite can improve the mechanical, thermal, and flame retardant properties of polymeric materials without hampering the optical translucency behaviour of the matrix. Since then, the majority of research has been focused in improving the physicochemical properties, e.g. mechanical, thermal, electrical, barrier etc. properties of polymer nanocomposites using cost effective and environmental friendly nanofillers with the aim of extending the applications of these materials in automotive, aerospace, construction, electronic, etc. as well as their day to day life use. The improvements in the majority of their properties have invariably been attributed... 

The field of nanocomposites was discovered in the 1960 s by the Toyota research group working on nylon-6 matrix, but only about ten years ago it was extended to other polymers including, e.g., polyolefins, polystyrene, poly(meth)acrylates, or polyesters, like poly(e-caprolactone). In the case of poly(e-caprolactone), Messersmith and Giannelis firstly evidenced the improvement of mechanical and barrier properties brought by the fine dispersion of the silicates within the polyester matrix. 

Recently, the advances in synthesis techniques and the abUity to characterize materials on atomic scale have led to a growing interest in nanosized materials. The invention of nylon 6/day nanocomposites by the Toyota Research Group of Japan heralded a new chapter in the field of polymer composites. Polymer nanocomposites combine these two concepts, that is, composites and nanosized materials. Polymer nanocomposites are materials containing inorganic components that have dimensions in nanometers. In this chapter, the discussion is restricted to polymer... 

A number of research groups worked on the total synthesis of gibberellins. The works of W. Nagata, E.J. Corey and F.N. Mander were reviewed by Mander.37 Other notable syntheses were Nagaoka s work on ( )-gibberellin A338 and Toyota and Ihara s work on gibberellin Ai2.39... 

A further group of nanocomposites are the well-known bentonites, revitalized at the end of the 1980s by Toyota Research. Bentonites are swellable, three-layer silicates consisting mainly of montmorillonite. The new organophilic bentonite Nanofil product family from Siid Chemie AG is based partly on the Bavarian calcium bentonites, which are activated by acid leaching [see Table 27 [77]], and do without cationic exchange. (Author s remark With a mean particle size of 4 pm, these are by no means nanoparticles ). 

In the early 1990s, Toyota researchers reported nylon-6-clay thermoplastic nanocomposites [176-178] and observed significant improvements in the mechanical properties (i.e., the modulus was doubled and the increase in strength was more than 50%) at 4.2 wt% clay loading. This inspired many research groups to extend their work on the formation of nanocomposites in many other polymer systems. Silicone rubber (SR) is one of the important functional elastomers and its properties such as high moduli, increased heat resistance, decreased gas permeability and flammability, etc., can be further improved by incorporating different dimensional nanofillers for their better performance in multifaceted applications. 

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