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Title: Viscosity Effects on Reaction Induced Phase Separation and Resulting Morphologies of Thermoplastic Toughened Epoxy Networks
This research investigates how reaction induced phase separation (RIPS) of thermoplastic, which occurs during glassy polymer network cure, is determined by viscosity. Utilizing high Tg engineering thermoplastics in high viscosity thermoset systems, dissolution of multiple loading levels of thermoplastic and thermoset pre-polymer conversion will be achieved through use of a high shear continuous reactor. Samples will be cured using various isothermal curing profiles and characterized for morphology type and domain size as well as rheologically to determine minimum viscosity, time to gelation, time from phase separation to gelation, and average viscosity. The influence of cure conditions, thermoplastic loading levels, thermoplastic composition, and molecular weight on structural morphology will be resolved, establishing a well-defined rheological well during cure that leads to tunable and controllable phase separated morphologies, from dispersed droplet to co-continuous. By controlling viscosity of thermoplastic dispersed network pre-polymers through phase composition, cure schedule, molecular weight, directed phase separation will be achieved. Rheological profiles will be related to resulting network structure, which will lead to the ability to control and direct complex thermoplastic filled thermoset systems to targeted unique morphologies.  more » « less
Award ID(s):
1659340
NSF-PAR ID:
10054413
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
CAMX: The Composites and Advanced Materials Expo
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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