The Effects of Molecular Architecture on the Rheological and Mechanical Properties of Polymeric Systems

The roles of molecular architecture and end-group functionality on the surface segregation characteristics of branched polymers in blends with commercially available linear polymers were also investigated. In the blends of branched PEIs with polystyrene (PS), the surface migration of PEIs correlates with the changes in their molecular architecture with xAB. However, the effects of configurational entropy, which depends on the molecular architecture, on the surface migration properties of blends are minute in comparison to the enthalpic effects, which are affected by the end-group chemistry of HBPs. Therefore, in order to minimize the interfacial energy, it was observed that the PEI HBPs with lower surface energies than PS segregated to the low energy air-interface, in turn decreasing the surface energy of PS films. On the other hand, higher surface energy PEI HBPs concentrate near the substrate, inhibiting the dewetting of low molecular weight PS. The miscibility of HBPs with linear low density polyethylenes (LLDPE) was found to depend on the length and concentration of alkane end-groups on HBPs. However, the addition of small amounts of PEI HBPs to LLDPEs was found to have a negligible effect on the rheological and processing properties of LLDPEs.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Sendijarevic, Ibrahim

Contributors dc:contributor

• McHugh, Anthony J.

• Engineering, Chemical

Language dc:language

eng

Identifier

(MiAaPQ)AAI3070432

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/82346