Miscibility with Polymer Matrix

The choice of a specific matrix is mainly experimental. The analyte must be miscible with the matrix and they must cocrystallize. For positive ionization acidic, proton donor matrixes are favored, and for negative ionization mode, basic matrixes. Hot spots may be generated during cocrystaUization if a nonuniform mixture is produced. Heterogeneity of the sample poses a major difficulty and in such a case the position of the laser beam may influence the spectra. In general, the selection of appropriate MALDI matrix, cationization salt, and sample concentration and sample preparation technique are critical success factors for obtaining a reliable mass spectrum that influence the polymer distribution. 

The rubber should not be miscible with the matrix polymer. 

There are situations where polymer blends may exhibit unique characteristics for utility in composite systems. One of these examples involves the segregation of conductive carbon black at the interface of phase separated polymer blends to yield a much lower concentration to reach the percolation threshold [ 1098,1099 ]. Another area of interest involves the addition of a polymer offering excellent adhesion to the filler as well as mechanical compatibility (or miscibility) with the matrix polymer. The polymeric interfacial agent can offer improved dispersion of this filler in addition to improved stress transfer across the interface between matrix and filler. The preferential concentration of filler particles in one phase is a situation... 

Another example showing unique properties of high-density brushes concerns the miscibility of the polymer brush with a chemically identical polymer matrix [154]. Neutron reflectometry was applied to a series of deuter-ated PMMA (PMMAj) brushes with a constant chain length (Mn = 46000, Mw/Mn = 1.08) and differing graft density (a 0.7 and 0.06 chains nm ). 

As an inorganic mineral, most unmodified nanoadditives are strongly hydrophilic and are generally compatible and miscible only with a few hydrophilic polymers, for instance, clay can only be made into PNs with polyethylene oxide),27 poly(vinyl alcohol),28 and a few other water soluble polymers. Most polymers are hydrophobic and thus they are neither compatible nor miscible with the unmodified nanoadditives, leading to an inability to achieve a PN with a good nanodispersion in most cases. Therefore, for most nanoadditives that have been used to prepare the PNs, an important and necessary feature is their surface treatment that provides compatibility to the nanoadditives and enables them to be uniformly dispersed (and/or separated into single nanoparticles) in the polymer matrix. 

Surface treatment of clays The surface treatment of the nanoadditives helps establish an interface with the polymer matrix and hence enhance the compatibility and/or the miscibility of the nanoadditive with the polymer matrix. In terms of the cationic silicate clay, such as MMT, the interface is... 

In designing a modifier, the first thing to be considered is the compatibility and the miscibility of the modifier with the polymer matrix. Compatibility48 may generally be considered to be a measure... 

Solvent blending Solvent blending, also called solution intercalation in the case of clay and other nanolayers, involves both dispersing the nanoadditive and dissolving the matrix polymer in a solvent or a solvent mixture. Three parameters have been considered to be important, particularly for clays, in choosing the surface treatment of the nanoadditives with this process The structure of the modifier, its miscibility with the polymer, and its thermal stability. The miscibility of the modifier here has two meanings miscibility with both the final polymer and the solvent chosen to dissolve the polymer. The modifier structure and its miscibility are perhaps more important than the thermal... 

When the mesogen moiety is included into the main chain of the polymer, the obtained macromolecule contains inherently rigid units, which usually result in remarkable mechanical properties and thermal stability. Fibers made by these polymers compete with the best ceramic fibers and are far superior to metal fibers [83]. They therefore are ideal candidates as reinforcements for polymer-based composites. However, these materials often have a poor miscibility and adhesion to other polymeric substrates, limiting the range of their applications. This problem basically arises from weak intermolecular interactions either within the liquid-crystalline polymer itself or with the matrix of the composite. Strong ionic... 

With the solvent deposition method, the drug and matrix polymer/macromolecule are dissolved in one organic solvent phase that is miscible with water. This solution is dispersed in an aqueous phase, and the organic solvent diffuses into the continuous water phase this leads to the precipitation of polymer and drug (deposition). 

---