P. Kubisa et T. Biedron, POLY(OXYETHYLENE)S TERMINATED AT BOTH ENDS WITH PHOSPHONIUM ION END-GROUPS .2. PROPERTIES, Macromolecular chemistry and physics, 197(1), 1996, pp. 31-40
Poly(oxyethylene)s with number-average degrees of polymerization (DPn)
ranging from approximate to 6 to approximate to 80, terminated at bot
h ends with phosphonium ion end groups (diionic poly-EO), have been pr
epared and characterized as described in the preceding paper. Viscosit
ies of diionic poly-EO were measured, both in solution and in bulk. In
chloroform solution, at low concentration (< 1 g/100 mL), the viscosi
ty of diionic poly-EO was lower than the viscosity of nonionic (termin
ated with HO-groups) poly-EO of the same DPn. At higher concentrations
, the viscosity of diionic poly-EO exceeded that of nonionic poly-EO a
nd increased sharply with increasing concentration. At the constant we
ight concentration of approximate to 4 g/100 mL, the viscosities of sh
ort-chain diionic poly-EO were higher and those of longer chain diioni
c poly-EO were lower than the viscosities of the nonionic poly-EO of t
he same chain lengths. These results were attributed to a predominant
intramolecular aggregation of terminal ionic groups at low concentrati
on of ionic groups in solution and predominant intermolecular aggregat
ion at higher concentration of ionic groups. The results of bulk visco
sity measurements as well as the results of differential scanning calo
rimetry measurements of the dependence of the glass transition tempera
ture on the DPn of diionic poly-EO indicated that in bulk physically c
ross-linked networks were formed, due to intermolecular aggregation of
terminal ionic groups.