English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

A COMPOSITIONAL STUDY OF THE MORPHOLOGY OF 18-ARMED POLY (STYRENE-ISOPRENE ) STAR-BLOCK COPOLYMERS SEPTEMBER 1986 DOREEN SUE HERMAN B.S., UNIVERSITY OF PENNSYLVANIA M.S., UNIVERSITY OF MASSACHUSETTS Directed by: Professor Edwin L. Thomas This research explored the morphology of a series of 18 arm poly(styrene-isoprene) star-diblock copolymers as a function of the arm composition. Samples with composition increments of 10% polystyrene (PS) between 10 to 90* PS were examined with a closer look in the neighborhood of 30* PS. Samples were dissolved in toluene and slow cast into films 0.75 to 1.5 mm thick. Osmium tetraoxide staining provided contrast of cyromicrotomed sections for examination with a JEOL 100CX transmission electron microscope. The ordered bicontinuous double diamond (OBDD) structure was observed for the 33 and 3S% PS samples. All other samples exhibited those morphologies (spheres, cylinders or lamellae) expected for linear diblock samples of the same composition.

A compositional study of the morphology of 18-armed poly(styrene-isoprene) star block copolymers