Polymers 2012, 4(1), 187-210; doi:10.3390/polym4010187
Article

The Mechanical Properties of Epoxy Composites Filled with Rubbery Copolymer Grafted SiO2

1,* email, 2email, 2email, 3email, 3email and 1email
Received: 17 December 2011; in revised form: 5 January 2012 / Accepted: 6 January 2012 / Published: 16 January 2012
(This article belongs to the Special Issue Polymer-Inorganic Hybrids and Their Applications)
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract: This study demonstrated a method for toughening a highly crosslinked anhydride cured DGEBA epoxy using rubbery block copolymer grafted SiO2 nanoparticles. The particles were synthesized by a sequential reversible addition-fragmentation chain transfer (RAFT) polymerization. The inner rubbery block poly(n-hexyl methacrylate) (PHMA) had a glass transition temperature below room temperature. The outer block poly(glycidyl methacrylate) (PGMA) was matrix compatible. A rubbery interlayer thickness of 100% and 200% of the particle core radius was achieved by grafting a 20 kg/mol and a 40 kg/mol PHMA at a graft density of 0.7 chains/nm2 from the SiO2 surface. The 20 kg/mol rubbery interlayer transferred load more efficiently to the SiO2 cores than the 40 kg/mol rubbery interlayer and maintained the epoxy modulus up to a loading of 10 vol% of the rubbery interlayer. Both systems enabled cavitation or plastic dilatation. Improvement of the strain-to-break and the tensile toughness was found in both systems. We hypothesize that plastic void growth in the matrix is the primary mechanism causing the improvement of the ductility.
Keywords: toughened epoxy; rubbery interlayer; nanocomposites; RAFT polymerization
PDF Full-text Download PDF Full-Text [2281 KB, uploaded 16 January 2012 14:44 CET]

Export to BibTeX |
EndNote


MDPI and ACS Style

Gao, J.; Li, J.; Benicewicz, B.C.; Zhao, S.; Hillborg, H.; Schadler, L.S. The Mechanical Properties of Epoxy Composites Filled with Rubbery Copolymer Grafted SiO2. Polymers 2012, 4, 187-210.

AMA Style

Gao J, Li J, Benicewicz BC, Zhao S, Hillborg H, Schadler LS. The Mechanical Properties of Epoxy Composites Filled with Rubbery Copolymer Grafted SiO2. Polymers. 2012; 4(1):187-210.

Chicago/Turabian Style

Gao, Jianing; Li, Junting; Benicewicz, Brian C.; Zhao, Su; Hillborg, Henrik; Schadler, Linda S. 2012. "The Mechanical Properties of Epoxy Composites Filled with Rubbery Copolymer Grafted SiO2." Polymers 4, no. 1: 187-210.

Polymers EISSN 2073-4360 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert