Fluorinated synthetic mica

Sodium fluorinated synthetic mica was used to obtain organoclays [39]. Mica was treated with triphenyl-n-hexadecylphosphonium to produce PS nanocomposites by meltcompounding. The results indicated the advantages of synthetic versus natural clays with regard to flammability of nanocomposites. Synthetic clays have an advantage in color, purity, and batch-to-batch consistency when compared with natural clays. 

Data from the NIST consortium work also supports the assertion that a homogeneous residue is critical for providing the most effective heat-transfer barrier. Comparison of the mass loss rate data for three different PP/PP-g-MA/clay nanocomposites and pure PP-g-MA is shown in Figure 3.15. As the images of the residues show, little or no carbonaceous (black) material is present after gasification. The fluorinated synthetic mica (FSM) has the lowest mass loss rate this... 

Carbon nanofiberA iapor grown carbon nanofiber Carbon nanotubes Fluorinated synthetic mica Graphite oxide Layered double hydroxide Montmorillonite Multiwall carbon nanotubes Organically modified montmorillonite Polymer layered-silicate/Polymer-layered silicate nanocomposite... 

WAXS and TEM indicate a similar degree of dispersion to the melt-blended SAN-montmorillonite composite with 13.5% acrylonitrile and the SMA-montmorillonite composite with 25% MA discussed in the above work. The montmorillonite is dispersed well in the polystyrene and appears to be intercalated with polymer. Fluorinated synthetic mica (SOMASIF ME-100 manufactured by Co-op Chemical) was treated with the same quat and processes identical to the montmorillonite resulted in significantly inferior results. Sonication was demonstrated to be a significant processing variable for the preparation of improved polystyrene-montmorillonite composites. Unfortunately, no mechanical testing results were provided. 

Robert J-L, Beny J-M, Della Ventura G, Hardy M (1993) Fluorine in micas Crystal-chemical control of OH-F distribution between trioctahedral and dioctahedral sites. Eur J Mineral 5 7-18 Robert J-L, Hardy M, Sanz J (1995) Excess protons in synthetic micas with tetrahedrally coordinated divalent cations. Eur J Mineral 7 457-461 Rossman GR (1984) Spectroscopy of micas. Rev Mineral 13 145-181... 

Cooper and Hall [80] assessed from thermodynamic and experimental viewpoints the potential for synthetic mica to serve as the interface material in oxide-oxide composites. Natural micas contain water which renders them useless at high temperatures since their structure breaks down in the range 500-800°C. However, in synthetic micas it is possible to replace the OH ion with fluorine, i.e. P. This substitution increases the stability to temperatures exceeding 1200°C at ambient pressure [90, 91]. While this... 

In trioctahedral micas, the 0-H bond is pushed away from the (001) Of, plane and tends to lie along the perpendicular to this plane. Thus, some repulsive interaction with the interlayer cation occurs that weaken the stability of the structure. However, in oxidized (e g., Ohta et al. 1982) or fluorinated micas (e g., Takeda et al. 1971) this repulsion is reduced proportionally to the O -> OH or F OH" substitution. This is particularly evident in synthetic fluoro-micas (e g., Takeda and Burnham 1969). 

Kitaj ima K, Takusagawa N (1990) Effects of tetrahedral isomorphic substitution on the IR spectra of synthetic fluorine micas. Clay Minerals 25 235-241... 

Sakane H, Okabe M-0, Suzuki T (1997) Local stmeture of the interlayer ion in synthetic fluorine mica. J Phys IV 7, Colloque 2, Supplement J Physique III d Avril 1997, C2 1165-1166 Sayers DE, Lytle FW, Stem EA (1970) Point scattering theory of X-ray K absorption fine stmeture. Adv X-ray Anal 13 248-271... 

The addition of plasticizer used for the improvement of mechanical properties leads generally to an increase in the oxygen permeability coefficient due to the higher mobility of the polymer chain and higher free volume [102]. On the contrary, the dispersion of nanoclays in PLA makes it possible to divide the permeability coefficient by 2 or 3 depending upon the type of the nanoclays (e.g. organomodified montmorillonite, cloisite 25A or 30B, organomodified synthetic fluorine mica) and exfoliation [129-131]. 

Saponite modified by hexadecyltributylphosphonium cation. Synthetic fluorine mica modified by dipolyoxyethylene alkyl methylammonium cation. 

FIGURE 19.1 X-ray diffraction patterns and bright field transmission electron microscopy images of PLA nanocomposites prepared with organically modified synthetic fluorine mica. The number indicates amount of organoclay loading [27]. Reproduced from Ref. 27 with permission of American Chemical Society, USA. 

In subsequent research, Sinha Ray et al. [26,27] prepared PLA nanocomposites with organically modified synthetic fluorine mica (OMSFM). For the characterization of structure and morphology of prepared nanocomposites, they first... 

Additives used in final products Fillers antimony trioxide, aramid, barium sulfate, boron nitride, calcinated kaolin, carbon black, carbon fiber, glass fiber, glass spheres, mica, montmorillonite, talc, titanium dioxide, zinc borate Antistatics antimony-doped tin oxide, carbon nanotubes, polyaniline, polyisonaphthalene Antiblocking calcium carbonate, diatomaceous earth, silicone fluid, spherical silicone resin, synthetic silica Release calcium stearate, fluorine compounds, glycerol bistearate, pentaerythritol ester, silane modified silica, zinc stearate Slip spherical silica, silicone oil ... 

MAO and then the cationic metallocene catalyst Zr[i]-C6H5Me(thf)] was intercalated in two clays (a synthetic fluorinated mica-type silicate and the modified synthetic hectorite) by ion-exchange reaction with the interlamellar cations of the layered silicates. Figure 8 shows a schematic route for preparation of PP/clay nanocomposites. 

Wood T.E., Siedle A.R., Hill J.R., Skarjune R.P., Goodbrake C.J. Hydrolysis of aluminum—are all gels created equal Mater. Res. Soc. Symp. Proc. 1990 180 97-116 Yamabi S., Imai H. Crystalline phase control for titanium dioxide films by direct deposition in aqueous solutions. Chem. Mater. 2002 14 609-614 Yamaguchi T., Fujita T., Takusagawa N., Kitajima K. Complex formation of highly polymerized hydroxoaluminum polycations with synthetic expandable fluorine mica. Nippon Kagaku Kaishi 1996 307-310... 

Ray et al. [265] developed hionanocomposites based on PLA with OMMT by simple melt extrusion and found that intercalated nanocomposites exhibited remarkable improvement of materials properties as compared to PLA without clay. They also [266] used synthetic fluorine mica modified with N-(coco alkyl)-N,N-[bis(2-hydroxyethyl)-N-methylammonium cation for bionanocomposite preparation and found that all nanocomposites exhibited remarkable improvement of various materials properties with simultaneous improvement in biodegradability compared to neat PLA. The addition of MMT modified with trimethyl octadecylammo-nium cation to PLA, which was intercalated and well distributed in the matrix, was reported by Ray et al. [267] to produce PLA hionanocomposites with improved properties, especially their biodegradability in a compost environment (Figure 11.21). 

Addition of organically modified synthetic fluorine mica (OSFM) [341] to PBSA was also found to cause substantial enhancement in the mechanical properties of PBSA. For example, at room temperature, storage flexural modulus increased from 0.5 GPa for pure PBSA to 1.2 GPa for the nanocomposite, an increase of about 120% in the value of the elastic modulus. It was also observed that the stability of PBSA was increased moderately in the presence of OSFM. 

Synthetic substrates such as glass, quartz, mica, gold, silver and a wide array of polymers have been extensively used as base substrates for ESA deposition. Both hydrophilic (fluorine, glass and silicon) and... 

In subsequent research, Sinha Ray et al. prepared PLACNs with organically modified synthetic fluorine mica (OMSFM). For the characterization of structure and morphology of prepared nanocomposites they first used XRD and conventional TEM (CTEM), and then CTEM and high resolution TEM (HRTEM), they examined the final structure of PLACNs. The compositions of nanocomposites of PLA with OMSFM are summarized in Table 3.1. The XRD... 

Sinha Ray S, Okamoto K, Okamoto M (2006), Melt rheology and strain induced hardening behaviour of biodegradable poly(butylene succinate)/synthetic fluorine mica nanocomposites , Langmuir, submitted. 

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