Thioether glycidyl resins. VI. Reaction products of opening of oxirane ring of phenylthioetherglycidyl resin and of some derivatives under the influence of temperature

The process of oxirane ring opening of thioether glycidyl resins under various temperatures has been described. Reaction rate constants (k) and the activaton parameters (E_α, ΔH*, ΔS*) for epoxy group loss of 1,2-epoxy-3-(phenylthio)propane, 1,2-epoxy-3-(p-tolythio)propane, and 1,2-epoxy-3-(p-chloro-phenylthio)propane using classical kinetic methods were determined. The reaction products were separated and analyzed by means of chromatography and the structure of the compounds was determined by means of the spectral analyses: IR, ¹H-NMR, and ¹³C-NMR     

Koordinationsverbindungen von Aminoacridin-N-oxiden mit Metallthiocyanaten der 3d-Reihe

Coordination Compounds of Aminoacridine-N-oxides with Thiocyanates of the 3d Metals . Reactions of thiocyanates of the 3d metals with selected aminoacridine-N-oxides in homogeneous dilutions of N,N-dimethylformamide form compounds of the type [M(AAcNO)_a(DMF)_b(NCS)₂] · cDMF and [M′(AAcNO)_d(DMF)_e(NCS)₃] · fDMF, M = Mn²⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺; M′ = Cr³⁺, Fe³⁺; AAc^INO = 3,6-diamino-2,7-dimethylacridin-N-oxide, AAc^IINO = 3,6-bis(dimethylamino)acridin-N-oxide, AAc^IIINO = 2-ethoxy-6,9-diaminoacridin-N-oxide; a = 1, 2, 3, 4; b = 0, 1; c = 0, 1, 2, 3; d = 1, 2, 3; e = 0, 1, 2; f = 0, 1, 2, 3. The complexes are characterized by IR (4000–200 cm^?1) and UV-VIS spectra in solutions and solids and by EPR and conductivity investigations.     

Apparate

Ohne Zusammenfassung     

The behaviour of macromolecules in the flow through a sudden planar contraction

Analytic steady-state results for FENE-P model macromolecules, in the nearly coiled-up and nearly stretched state respectively, in general two-dimensional flow fields are derived. These results are utilized in the flow through a sudden planar contraction. Special emphasis is devoted to the structure tensor R R, which furnishes, among other things, the mean square extension and the average orientation of the macromolecules.     

Slow flow of a non-Newtonian fluid past a micro-capsule

The streaming motion past a spherical microcapsule is studied. The particle consists of a thin elastic membrane enclosing an incompressible fluid. Since the problem is highly nonlinear, a perturbation solution is sought in the limiting case where the deviation from sphericity is small. Obviously, the capsule remains nearly spherical when λ, the ratio of viscous forces to elastic (shape-restoring) membrane forces is small. In this limit, the rheology of the inside fluid is immaterial and the problem is essentially characterized by three parameters: λ, the Reynolds number Re (interia effect), and the Weissenberg number We (non-newtonian effect). The deformation is obtained explicitly under the restriction We<1, Re<1. It is shown that to leading order, the capsule deforms exactly into a spheroid which can be either oblate or prolate, depending mainly upon the elasticity number We/Re: for We/Re<0.57 the spheroid is oblate, while for We/Re>0.81 a prolate spheroid results. For 0.57<We/Re<0.81 additional details of the rheology of the membrane and of the suspending fluid are needed. The degree of the deformation is governed by the parameters λ Re. All parameters of the problem enter into the expression of the drag force. On a qualitative basis, these results are similar to those for droplets although major differences exist quantitatively.     

Dilute polymeric solutions close to bounding surfaces: Shear stresses in equilibrium

The problem of a dilute polymer solution in equilibrium close to a wall, an edge, and a corner, respectively, is studied theoretically. Detailed knowledge of the rheology in these regions is needed in order to obtain the proper boundary conditions for bulk variables. It is interesting to see that shear stresses are predicted, whose origin is based on the intramolecular (elastic) interaction between the beads.     

A phenomenological model of electrorheological fluids

The fundamental assumption of the paper is that the extra stress tensor of an electrorheological fluid is an isotropic tensor valued function of the rate of strain tensor D and the vector n (which characterizes the orientation and length N of the fibers formed by application of an electric field). The resulting constitutive equation for is supplemented by the solution of the previously studied time evolution equation for n. Plastic behavior for the shear and normal stresses is predicted. Anticipating that the action of increasing shear rate is i) to orient the fibers more and more in the direction of flow and ii) simultaneously to break up the fibers leads to the conclusion that for the same behavior is encountered as without an electric field. Using realistically possible approximation formulas for the dependence of and N on leads to the Bingham behavior for and power law behavior for large shear rates.