Organo-modifier

Plasticized PLA-based nano-composites were prepared and characterized with polyethylene glycol and MMT. It is reported that the organo-modified MMT-based composites show the possible competition between the polymer matrix and the plasticizer for the intercalation between the alumino-silicate layers (Paul et ah, 2002). 

Paul, M., Alexandre, M., Degee, P., Henrist, C., Rulmont, A., and Dubois, P. 2002. New nanocomposite materials based on plasticized poly(L -lactide) and organo-modified montmorillonites thermal and morphological study. Polymer 44 443-450. 

Plouet, M.R., Vilminot, S., Guillot, M. and Kurmoo, M. (2002) Canted antiferromagnetism in an organo-modified layered nickel phyllosilicate. Chemistry of Materials, 14, 3829—3836. 

Organo-modified natural zeolites as new tailored natural materials for removal of cations, anions and even organic pollutants may present fairly large potential for water utility companies. The topic of this study was to examine the oxyanions removal from waters by octadecylammonium-enriched inland clinoptilolite. The 18-carbon chain consisting surfactant attached on the clinoptilolite surface, as to the organic acids of living bodies comparable substances, makes the treatment process economic on scale and cost-effective as well.7... 

Floyd, D. T. Jenni, K. R. Silicone Polymers, Organo-Modified (Application in Personal Care Products). In Polymeric Materials Encyclopedia, Salamone, J. C., Ed. CRC Press Boca Baton, 1996 Vol. 10, pp 7677-7688. 

The morphology of rubber-based nanocomposites also seems to change in the presence of compounding ingredients [89, 90]. HNBR, when melt-compounded with organo-modified sodium montmorillonite clays (o-MMTs) prior to sulfur curing, resulted in the formation of nanocomposites with exfoliated or intercalated structures. In stark contrast, under similar conditions HNBR compounded with unmodified sodium montmorillonite clays (NA) formed microcomposites [90]. This was traced to its reactivity with the sulfur in the presence of amine-type organomodifiers. 

On the other hand, Bhattacharya et al. have reported the plasticization effect of organically modified layered silicates on dynamic mechanical properties [13]. In this work, nanocomposites of SBR have been prepared using various nanofillers like modified and unmodified montmorillonite, SP, hectorite etc. It has been observed that the Tg shifts to lower temperature in all the nanocomposites, except for systems from hectorite and NA. This is due to the fact that clay layers form capillaries parallel to each other as they become oriented in a particular direction. Due to wall slippage of the unattached polymer through these capillaries, the Tg is lowered, which could be even more in the absence of organo-modifiers [13]. A similar type of plasticization effect is also noted in the case of the low... 

There are several major areas of interfacial phenomena to which infrared spectroscopy has been applied that are not treated extensively in this volume. Most of these areas have established bodies of literature of their own. In many of these areas, the replacement of dispersive spectrometers by FT instruments has resulted in continued improvement in sensitivity, and in the interpretation of phenomena at the molecular level. Among these areas are the characterization of polymer surfaces with ATR (127-129) and diffuse reflectance (130) sampling techniques transmission IR studies of the surfaces of powdered samples with adsorbed gases (131-136) alumina(137.138). silica (139). and catalyst (140) surfaces diffuse reflectance studies of organo- modified mineral and glass fiber surfaces (141-143) metal overlayer enhanced ATR (144) and spectroelectrochemistry (145-149). 

The clay is first dispersed in water or an aqueous system (to form a suspension) and the modifier that has been pre-dissolved in water (or an aqueous system) is then gradually (drop-wise) added to the clay suspension. The organo-modifier will be anchored onto the surface of the clay platelets immediately after it is added but further stirring for some more time up to a few hours may be needed to achieve homogeneous and complete ion exchange. Some representative modifiers (in both cationic and anionic form) that have been used as surface treatment for the clays in the literature are shown in Figure 11.9. 

For more than a decade, numerous research studies have been carried out on the flame-retardant properties conferred by nanoparticles and mainly by organo-modified layered silicates (OMLS). Earlier work at Cornell University and National Institute of Standards and Technology in the United States showed that nanocomposites containing OMLS reduced polymer flammability and enhanced the formation of carbonaceous residue (char).14 Owing to a strong increase in polymer viscosity, impairing processability, and also due to the breakdown of ultimate mechanical properties, the acceptable rate of incorporation for nanoparticles to improve flame retardancy is generally restricted to less than 10 wt %. 

F. Laoutid, P. Gaudon, J.M. Taulemesse, J.M. Lopez-Cuesta, J.I. Velasco, and A. Piechaczyk, Study of hydromagnesite and magnesium hydroxide based fire retardant systems for EVA containing organo-modified montmorillonite, Polym. Degrad. Stabil., 2006, 91 3074—3082. 

The ceramizing capacity of polyboroxosiloxane elastomer provides a new P-free intumescent mechanism [57], The combustion of PP-polyboroxosiloxane 3 1 blend filled with 1.25% organo-modified SEP (OSEP, Pangel B40 product of Tolsa Ltd.) and 1.25% melamine borate lead to the formation of white foamed ceramic structure shown in Figure 13.15. 

Zammarano, M., Bellayer, S., Gilman, J. W., Franceschi, M., Beyer, F. L., Harris, R. H., and Meriani, S., 2006. Delamination of organo-modified layered double hydroxides in polyamide 6 by melt processing. Polymer 47 652-62. 

An overview is presented of antifoam chemistry from Degussa and its application to the production and formulation of organo-modified siloxane anti-foaming agents for polyvinyl chloride. 7 refs. 

Long-term stability under exposed conditions, implying a permanent anchoring of the hard silicone resin network (organo-modified quartz structure) to the substrate. 

Interestingly, porous materials can act as templates for synthesizing other porous materials, as, for example, the application of MOFs (Liu et al., 2008) and organo-modified LDHs (Leroux et al., 2006) for porous carbon synthesis. 

Leroux. E, Raymundo-Pinero, E., Fedelec. J.-M.. and Beguin, F. 2006. Textural and electrochemical properties of carbon replica obtained from styryl organo-modified layered double hydroxide. Journal of Materials Chemistry 16, 2074-2081. 

Figure 2.2 Schematic illustration of exfoliated organo-modified clays with immobilized enzyme molecules.

Tegopren . [Goldschmidt] Organo modified siloxanes surfactants used as antistats, wetting and leveling agents, emulsifiers, dispersants, and fm the improvement of lubricity additive for polishes. 

The hydrosilylation reaction is a widely used method for the S5mthesis of organo-modified silanes and siloxanes. The addition of Si-H to C-C double bonds is usually catalyzed by homogenous or colloidal Pt catalysts. The major drawback of this reaction is that the catalyst cannot easily be removed from the product after completion of the reaction. To lower the losses of precious metal catalysts, the amount of catalyst is usually decreased, but this decreases reaction speed. Degussa has managed to develop an elegant biphasic approach to run the hydrosilylation reaction [17] (Scheme 9-8). 

Pluta et al. investigated PLA/MMT nanocomposites by studying the dispersions of modified and unmodified MMT prepared by melt blending. XRD showed that the good affinity between the organo-modified clay and the PLA was sufficient to form an intercalated structure in the nanocomposite. TGA showed that... 

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