PE-b-PEO block copolymer nanostructured thermosetting systems as template for TiO 2 nanoparticles

Two different, molecular weight and blocks ratio, poly(ethylene-b-ethylene oxide) block copolymers (PE-b-PEO) were used as nanostructuration agent for epoxy based thermosets and as surfactant for sol-gel synthesized titanium dioxide (TiO2) nanoparticles. Obtained DSC results confirmed the miscibility of PEO block of PE-b-PEO block copolymer with epoxy monomer in PE-b-PEO/DGEBA unreactive mixtures and with DGEBA/MCDEA matrix in cured systems modified with PE-b-PEO block copolymer without or with TiO2 nanoparticles. The dilution effect caused by the addition of PE-b-PEO block copolymer on the epoxy/amine reaction mixture was verified. AFM phase images proved that nanostructured thermosetting systems can be reached in function of PE-b-PEO block copolymer content. Good dispersion and, in the case of the cured systems modified with higher molecular weight and higher PEO content PE-b-PEO block copolymer, selective localization of TiO2 nanoparticles can be achieved. The morphology of investigated thermosetting systems and the good dispersion of TiO2 nanoparticles depend on the PEO block content in PE-b-PEO block copolymer and its molecular weight. Transparent PE-b-PEO block copolymer nanostructured thermosetting systems with hydrophilic character and well dispersed or positioned TiO2 nanoparticles can be obtained.