POLYMERIC REINFORCEMENT

SAR studies were carried out by de Bruyne et al. [92] on a series of dimeric procyanidins, considered as model compounds for antiviral therapies. On the whole, proanthocyanidins containing EC dimers exhibited more pronounced activity against herpes simplex virus (HSV) and human immunodeficiency virus (HIV), while the presence of ortho-trihydroxyl groups in the B-ring appeared to be essential in all proanthocyanidins exhibiting anti-HSV effects. Galloylation and polymerization reinforced the antiviral activities markedly. 

Keywords Blends Plasma polymerization Reinforcing fillers Rubber Surface polarity Vulcanization... 

The polymeric reinforcing fibers while having surfaces which are less hydrophilic, can absorb water in bulk to about a percent by weight. This amount of material on a... 

Figure 1. Tensile Strength Variation versus Clay Content (With and without polymeric reinforcement).

In general, most clayey sands can be successfully stabilized with lime [2]. However, the addition of polyamide 66 strips can significantly improve the engineering properties of stabilized clayey sand and moderates the cracks propagation. A typical cracks distribution in a polymeric reinforced specimen in tension as well as in compression is shown in Figures 3 and 4 respectively. The overall results of this study indicate that lime/polyamide stabilizer composite is performing adequately. 

Figure 3. A typical cracks patterns in a polymeric reinforced specimen in the indirect tensile test.

The effect of various additives on a styrene polymerization reinforces the tentative conclusion that vinyl polymerization is not taking place. Even though yields were increased by halogenated additives they were not decreased by additives expected to act as scavengers for free-radical species (benzophenone) or ionic species (butylamine or water). Under an assumed mechanism of fragmentation and rapid recombination to condensed products, halogenated compounds additives may serve to increase the efficiency of energy transfer from the electric field to the monomer. 

Reinforced polyurethane resins are often used in a molding process called reactive injection molding (RIM), also known as resin-transfer molding. Polyurethanes are selected for their low viscosity and rapid polymerization. Reinforced applications include large automotive parts and building components. 

S.6 Other Natural and Synthetic Polymeric Reinforcing Fibres... 

Morales et al. [323] prepared bionanocomposites of PEA (derived from glycohc acid and 6-aminohexanoic add by in situ polymerization) reinforced with OMMTs. The most dispersed structure was obtained by addition of C25A organoclay. Evaluation of thermal stability and crystallization behavior of these samples showed significant differences between the neat polymer and its nanocomposite with C25A. Isothermal and nonisothermal calorimetric analyses of the polymerization reaction revealed that the kinetics was highly influenced by the presence of the silicate particles. Crystallization of the polymer was observed to occur when the process was isothermally conducted at temperatures lower than 145 °C. In this case, dynamic FTIR spectra and WAXD profiles obtained with synchrotron radiation were essential to study the polymerization kinetics. Clay particles seemed to reduce chain mobility and the Arrhenius preexponential factor. 

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