Turbulence in dilute polymer solutions when polymers are strongly stretched by the flow is investigated. We establish power-law spectra of velocity, that are not associated with a flux of a conserved quantity, in two cases. First, such spectrum is formed in the elastic waves range of high Reynolds number turbulence of polymer solutions above the coil–stretch transition. Second, such spectrum is...

The industrial importance of penetrable and/or impenetrable polymer systems is evident when one faces with a huge number of publications considering various aspects of diffusion phenomenon. Strong worldwide interest to realize more details about the fundamental of the process, generalize the governed laws to new findings, and find fast and reliable techniques of measurement, makes motivation to...

Polymers show universal behavior at long length and time scales. In this chapter, the equilibrium and dynamics of dilute polymer solutions is presented in terms of theoretical models that form the basis of polymer physics. The size of an ideal polymer is calculated from the freely jointed chain model, the freely rotating chain model and the Gaussian equivalent chain model. The Edwards Hamiltoni...

We study irreversible polymer adsorption from dilute solutions theoretically. Universal features of the resultant non-equilibrium layers are predicted. Two broad cases are considered, distinguished by the magnitude of the local monomer-surface sticking rate Q: chemisorption (very small Q) and physisorption (large Q). Early stages of layer formation entail single-chain adsorption. While single-c...

2014 Starting with the Flory theory for one long flexible polymer chain of N segments in a homopolymer melt of shorter (P segments) chains, we employ scaling arguments to construct the « phase diagram » of an athermal bimodal solution, i.e. a ternary system composed of N chains, P chains, and solvent. Qualitatively the presence of short chains reduces the effective solvent quality as experience...

Small angle neutron scattering is employed to estimate the interactions in complex multicomponent systems. The method is applied to describe a ternary system, poly(dimethyl siloxane) toluene with silica filler particles. Contrast variation by solvent deuteration is used to distinguish the three different partial structure factors of filled polymer samples, S(pp)(q), S(pf)(q), and S(ff)(q), wher...

We consider directed path models of a selection of polymer and vesicle problems. Each model is used to illustrate an important method of solving lattice path enumeration problems. In particular, the Temperley method is used for the polymer collapse problem. The ZL method is used to solve the semi-continuous vesicle model. The Constant Term method is used to solve a set of partial difference equ...

Dilute or semidilute solutions of nonintersecting self-avoiding walk ~SAW! polymer chains are mapped onto a fluid of ‘‘soft’’ particles interacting via an effective pair potential between their centers of mass. This mapping is achieved by inverting the pair distribution function of the centers of mass of the original polymer chains, using integral equation techniques from the theory of simple f...

A model is described which explains drag reduction (DR) in dilute polymer solutions in terms of solvation of macromolecular chains and formation of relatively stable domains. The domains partly suppress the vortex formation, act as energy sinks, and also play a role in mechanical degradation in flow (MDF). We report ultrasonically determined solvation numbers for a series of copolymers with the...

Ideal dilute solutions, electrolyte solutions, regular solutions, regular polymer solutions and fused salts have been considered widely different systems. Yet an idealization of completely randommixingbythermal motion is adequate in these systems. In this respect these solutions are similar. Such recapition yielded a new concept, i.e., "Organized So lutions" . From the comparison of characteris...