Nanostructures and surface hydrophobicity of self-assembled thermosets involving epoxy resin and poly(2,2,2-trifluoroethyl acrylate)-block-poly(ethylene oxide) amphiphilic diblock copolymer.
Poly(2,2,2-trifluoroethyl acrylate)-block-poly(ethylene oxide) (PTFEA-b-PEO) amphiphilic diblock copolymer was synthesized via the reversible addition-fragmentation transfer polymerization of 2,2,2-triffluroethyl acrylate with dithiobenzoyl-terminated poly(ethylene oxide) as a chain-transfer agent. The amphiphilic diblock copolymer was incorporated into epoxy resin to prepare the nanostructured epoxy thermosets. The nanostructures were investigated by means of atomic force microscopy, small-angle X-ray scattering, and dynamic mechanical analysis. In terms of the miscibility of the subchains of the block copolymer with epoxy after and before curing reaction, it is judged that the formation of the nanostructures follows the mechanism of self-assembly. The static contact angle measurements indicate that the nanostructured thermosets containing PTFEA-b-PEO diblock copolymer displayed a significant enhancement in surface hydrophobicity as well as a reduction in surface free energy. The improvement in surface properties was ascribed to the enrichment of the fluorine-containing subchain (i.e., PTFEA block) of the amphiphilic diblock copolymer on the surface of the nanostructured thermosets, which was evidenced by surface atomic force microscopy and energy-dispersive X-ray spectroscopy.
Yi
Fangping
F
Department of Polymer Science and Engineering and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, P R China.
Zheng
Sixun
S
Liu
Tianxi
T
D000179:Acrylates / Q000138:chemical synthesis / Q000737:chemistry*; D004853:Epoxy Resins / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D015394:Molecular Structure; D049329:Nanostructures / Q000737:chemistry*; D010316:Particle Size; D011092:Polyethylene Glycols / Q000138:chemical synthesis / Q000737:chemistry*; D013499:Surface Properties; D013696:Temperature
D000179:Acrylates; D004853:Epoxy Resins; C540040:poly(2,2,2-trifluoroethyl acrylate)-block-poly(ethylene oxide); D011092:Polyethylene Glycols