Synergistic interactions, combined polymers

These were prepared by a solution polycondensation of a (phenol) and a bis(acid chloride) as shown in Scheme 3 [24, 25]. The resulting polymers (Table 2) again show broad LC phases due to the synergistic interaction of the main-chain and side-chain mesogenic groups. However, compared to the other types of combined LC... 

Surface tension provides a particularly useful and informative approach to studying interaction in polymer/surfactant pairs in the case where the polymer alone is inactive or only feebly active at the air/water interface. Such is the case with many polyelectrolytes including the well-known conditioning agent Polymer JR 400. Goddard and co-workers, in then-studies of this polymer in combination with SDS, showed that a strong synergistic reduction of surface tension occurred (57,58). This behavior is quite different from that observed in systems with nonionic polymers. The effect is evident at low concentrations of SDS (Fig. 14) and implies that the polymer of normally feeble surface activity is transformed. 

The quantitative relationship of flammability of a polymer with respect to the concentration of flame retardant is usually not linear, and there is no logical reason to expect combinations of different flame retardants to show a linearly additive result either (43). The actual result is often found to be "synergistic" or "antagonistic", or in regression analysis terminology, the interaction term is often found to be statistically significant. 

Hybrid materials which combine the electronic conductivity of thiophene-conjugated polymers and the redox and optical properties of metal complexes are being developed to take advantage of synergistic electronic interactions. 

Combining different stabilizers acting with different mechanisms may trigger a synergistic effect that can provide excellent protection to the polymer. On the other hand, some combinations result in antagonistic interactions that reduce the efficacy of the stabilizers. 

The cooperative interaction between two or more antioxidants (or antioxidant fimctions) that enhances the stabilization of a polymer by more than the sum of the individual effects of the antioxidants is referred to as synergism. Often, the overall effectiveness of the synergistic system is much greater than can be achieved by either of the antioxidants, even at higher concentration, and hence the practical importance of synergism. Synergism can result from the combined action of two... 

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