Thermodynamic and Structural Properties of Polystyrene-Polybutadiene-Polystyrene Block Copolymers

Abstract

We have evaluated the translational friction coefficient of wormlike cylinders by the Oseen-Burgers procedure. The final results may be written in terms of only the molecular dimensions. From the point of view of classical hydrodynamics, the Ullman theory is not correct; it is correct only when his parameter a (friction constant per unit length) is taken as infinity. The Hearst-Stockmayer theory is not unphysical, though its application leads to small-er estimates of the diameter of the cylinder than does the present theory in the case of typical stiff chains. An analysis of the intrinsic viscosity of wormlike cylinders will be given in the next paper.

Small-angle x-ray diffraction study of thermal transition in styrene-butadiene block copolymers

“…When a spherical particles of radius a are imbedded in a continuous matrix, 1 is given by P Ip 3 ia(l-I ) (18) l being the volume fraction of the spheres. In Model I l remains equal to the initial value 0.25 at all temperatures, and 1p is then equal to the radius a.…”

Sustainable thermoplastic elastomers derived from renewable cellulose, rosin and fatty acids

“…First generation TPEs consist of ABA triblock copolymers in which hard minority domains of block A are microphase-separated within a so matrix of block B. Triblock copolymers, including polystyrene-b-polybutadiene-b-polystyrene (SBS) and polystyrene-b-polyisoprene-b-polystyrene (SIS) synthesized by anionic polymerization, have been used as commercial TPE materials for several decades. [16][17][18] Also (meth)-acrylic based ABA triblock copolymers such as poly(methyl methacrylate)-b-poly(n-butyl acrylate)-b-poly(methyl methacrylate) (PMMA-b-PBA-b-PMMA) prepared by atom transfer radical polymerization (ATRP) have been reported as TPE materials.…”

“…The T g values for these samples (Fig. 4(A)) are about [10][11][12][13][14][15][16][17][18][19][20] C below ambient temperature. These observations suggest an optimal DAEMA content between 25 and 40 mol% leads to gra copolymers with a suitable balance between side-chain attraction (imparting elastic character and ability to support tensile stress) and chain disentanglement (enabling large strain deformation and postponing failure to higher strains).…”

Recent developments in polymer applications of small-angle neutron, X-ray and light scattering

“…Earlier work on the SAXS from block copolymers was carried out by Skoulios (1973), McIntyre (McIntyre & Campos-Lopez, 1970: Campos-Lopez, McIntyre & Fetlers, 1973 and Lewis & Price (1971), who were able to characterize the superlattices of domain arrangement in block copolymers having narrow block molecular weight distributions. More recent work has come from the laboratory of Wada (Kurita, Tagawa, Hiramatsu, Sano & Wada, 1976) with a typical result shown in Fig.…”