Polymer particle interactions

The preceding section illustrates the variety of phenomena that may be observed in polymer-colloid-solvent mixtures. Polymer dissolved in a colloidal suspension is in some ways similar to ionic solutes responsible for electrostatic effects. Interactions between colloidal particles and polymer generate nonuniform distributions of polymer throughout the solution. Particle-particle interactions alter the equilibrium polymer distribution, producing a force in which sign and magnitude depend on the nature of the particle-polymer interaction. The major difference between polymeric and ionic solutions lies in the internal degrees of freedom of the polymer. Thus, a complete treatment of particle-polymer interactions requires detailed consideration of the thermodynamics of polymer solutions. 

An alternative method commonly used to determine the polymer radius of gyration is the Zimm s method [49], It follows from Eq. 8 upon assumption of weak interparticle correlations [p(6) = P(0) = P(q)] and on the assumption that particles (polymers) interact with each other through only one segment of each particle at a time, which is the better fulfilled the lower the concentration. It holds then that... 

The ternary blends mentioned, nonetheless, are used in stretch and thermoshrinkable films in the packing industry and in the agricultural uses to protect crops. In this regard, an improved understanding of the particle-polymer interactions may motivate the formulation of new materials with specific properties. 

The properties of polymers depend to a large degree on the conformations available to their chains. The presence of solid, particulate material can significantly modify these conformations, even in the absence of any particle-polymer interaction or other effects such as already discussed. 

Resilience/Hysteresis - Resilience is essentially a measure of rubber elasticity - the characteristic ability to quickly return to original shape following deformation. Unfilled elastomers are at their peak resilience because there is no obstacle to elastomer chain extension and contraction (return to randomness). The introduction of a filler creates such an obstacle in proportion to the strength of the particle-polymer interaction. Resilience is therefore generally in inverse proportion to filler loading and reinforcement. 

Xgp) are independent variables. They were able to establish that the chemical nature of the particles influences the stability in the particle-polymer interaction space of the system. In their experiment, they varied (i) the volume fraction of nanoparticles, (ii) blend composition, particle radius and chain length and from the results obtained, they concluded that ... 

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