Dilute-Solution Behavior of a Rigid Polymer, Poly[trans-bis(tributylphosphine)platinum 1,4-butadiynediyl]

Abstract

ABSTRACT:Poly[trans-bis(tributylphosphine)platinum I ,4-butadiynediyl] (PPBD) in heptane at 25cC was studied by viscosity and sedimentation velocity measurements over a range of weightaverage molecular weight Mw from 7 x 10 3 to 1.4 x 10 5 Although the chemical structure of PPBD suggests a very rigid nature of the chain, the measured value 1.1 for the exponent in the Mark-Houwink-Sakurada [IJ] (intrinsic viscosity)-Mw relation indicated an appreciable flexibility of the chain. The data for [IJ] and sedimentation coefficient as functions of M w were analyzed by the Yamakawa-Fujii theories for a wormlike cylinder, yielding ML = 810± 60nm -l, q= 13 ± 3 nm, and d= 1.2 ± 0. 3 nm, where M Lis the molecular weight per unit contour length, q is the persistence length, and dis the diameter of the cylinder. The flexibility ofPPBD indicated by this q value is comparable to that of cellulose nitrate which is known to be a typical stiff polymer. solvents were essentially independent of solvent (about 1.2x 10 2 cm 3 g-1 ) and that the exponent in the Mark-Houwink-Sakurada relation between [17] and weight-average molecular weight M w was close to I. 7.These preliminary results indicate that PPBD can be used as a model substance for investigating rodlike polymers in solution. In contrast with aromatic polyamides, considered model substances for rodlike molecules, 5 -7 PPBD does not involve the problem of difficulty in solubility; Hagihara et al. found that it dissolves in a number of common organic solvents. This is a very inviting feature for a solution study of PPBD.

Organometallic Polymers with Transition Metals in the Main Chain

“…The intrinsic viscosities of this and related polymers, [η] = 1.19−1.25, were found to be independent of the nature of the solvent, and the solubility parameter δ was found to be in the range of 6.6−9.7 (cal/mL) 1/2 . , In addition, the α-value in the Mark−Houwink equation (ca. 1.7) was also determined and indicates that this type of polymer has a stiff rodlike structure in solution. , However, it is worth noting that subsequent studies on the same polymer by Fujita and Tabata and their co-workers suggested that the polymer chain is more flexible and can be best represented by a wormlike model.…”

“…1.7) was also determined and indicates that this type of polymer has a stiff rodlike structure in solution. 172,174 However, it is worth noting that subsequent studies on the same polymer by Fujita 218 and Tabata 219 and their co-workers suggested that the polymer chain is more flexible and can be best represented by a wormlike model.…”

Entanglement Effects in Semiflexible Polymer Solutions. 2. Huggins Coefficient and Inclusion of Intermolecular Hydrodynamic Interactions

“…The linear extrapolation of the data shown in Figure to p = 1 seems to give a value of k ‘ HI that is consistent with those theoretical values.

3 Axial ratio dependence of k ‘ HI for various solutions of nearly rodlike polymers with N ≲ 0.8; (□) PHIC−DCM; (○) PHIC−toluene; (·) PHIC− n -butyl chloride; (⊡) schizophyllan−water; , (▵) xanthan−0.1 M aqueous NaCl; , (⊙) poly(γ-benzyl l -glutamate)−dimethylformamide; (◇) poly[ trans -bis(tributylphosphine)platinum 1,4-butadiynediyl]−heptane; (▴) poly(terephthalamide- p -benzohydrazide)−dimethyl sulfoxide

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Orientational Characteristics of Semiflexible Poly(yne)–Platinum Polymers as Studied by Deuterium NMR

“…Following our previous treatment, 10 we compare these experimental S-vP plots with those calculated from the Flory-Ronca lattice theory.11 In consideration of the chain flexibility, theoretical calculations for poly(yne)-platinum polymers were carried out on the basis of the Kuhn-chain assumption, 12 the axial ratio of the Kuhn segment xk being estimated to be 22 from the persistence length an~ the diameter of the polymer. 2 The variations of S in the anisotropic phase are illustrated by the solid curves, and the broken curves indicate the results of calculations extended over the concentration range where the biphasic equilibrium should be expected. The values of S at the boundary between these curves define Scrit· Afthough the theory predicts approximately acceptable values for the isotropic-anisotropic phase equilibrium concentration (vp), a large difference is demonstrated between the calculated and observed order parameters (S).…”

“…Fujita, Teramoto et al 2 have reported solution properties of poly[trans-bis(tri-nbutylphosphine )platinum 1, 4-butadiynediyl] f Pt(PBU3b-C=C-c=ct…”