Nanocavitation in self-assembled amphiphilic block copolymer-modified epoxy

Jia Liu, Hung Jue Sue, Zachary J. Thompson, Frank S. Bates, Marv Dettloff, George Jacob, Nikhil Verghese, Ha Pham

Research output: Contribution to journalArticlepeer-review

147 Scopus citations

Abstract

An amphiphilic block copolymer toughener was incorporated into a liquid epoxy resin formulation and self-assembled into well-dispersed nanometer scale spherical micelles with a size of about 15 nm. The nanosized block copolymer at 5 wt% loading can significantly improve the fracture toughness of cured epoxy thermosets without reduction in modulus at room temperature and with only a slight drop in glass transition temperature. The toughening mechanisms were investigated, and it was found that the 15 nm size block copolymer micelles could cavitate to induce matrix shear banding, which mainly accounted for the observed remarkable toughening effect. Other mechanisms, such as crack tip blunting, may also play a role in the toughening. A discussion of the possible reasons responsible for the observed attractive mechanical property improvements due to the block copolymer modification is given. Implications of the present finding for designing toughened polymers are also discussed.

Original languageEnglish (US)
Pages (from-to)7616-7624
Number of pages9
JournalMacromolecules
Volume41
Issue number20
DOIs
StatePublished - Oct 28 2008

Fingerprint Dive into the research topics of 'Nanocavitation in self-assembled amphiphilic block copolymer-modified epoxy'. Together they form a unique fingerprint.

Cite this