Premium
New polyisobutylene‐based model elastomeric ionomers: RheoLogical behavior
Author(s) -
Bagrodia S.,
Wilkes G. L.,
Kennedy J. P.
Publication year - 1986
Publication title -
polymer engineering and science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.503
H-Index - 111
eISSN - 1548-2634
pISSN - 0032-3888
DOI - 10.1002/pen.760261004
Subject(s) - zinc stearate , ionomer , elastomer , materials science , polybutadiene , ionic bonding , polymer chemistry , plasticizer , zinc , viscosity , rheology , telechelic polymer , chemical engineering , copolymer , composite material , polymer , chemistry , organic chemistry , end group , raw material , ion , engineering , metallurgy
The rheological behavior of sulfonated polyisobutylene based elastomeric ionomers has been studied. The effects of molecular architecture, type of cation, and addition of excess neutralization agent were investigated. The effect of temperature was studied to a limited extent. In a specific case, the influence of an ionic plasticizer, zinc stearate was also examined. It was found that in these telechelic ionomers where the ionic groups are located exclusively at the chain ends, significant Ionic interactions may persist even at 180°C. The zinc‐neutralized ionomers had the lowest viscosity as compared to the corresponding potassium‐ or calcium‐neutralized ionomers. The covalent character of zinc is believed responsible for this behavior. Other factors being constant, the triarm based ionomers are more viscous than the monofunctional ionomers. A mixture of monofunctional ionomers with the triarm, species is a model for dangling chain ends, and results in a slight lowering of the viscosity under the conditions studied. Zinc stearate acts as an ionic plasticizer. Upon the addition of 15 percent by weight of zinc‐stearate to the ionomer, the low shear rate viscosity drops by several orders of magnitude and renders the ionomer thermally processable at moderate temperatures.