Differently-catalyzed silica-based precursors as functional additives for the epoxy-based hybrid materials. (2nd September 2016)

• Record Type: Journal Article
• Authors: Perchacz, Magdalena; Beneš, Hynek; Zhigunov, Alexander; Serkis, Magdalena; Pavlova, Ewa
• Is Part Of: Polymer. Volume 99(2016)
• Page Start: 434
• Page End: 446
• Publication Date: 2016-09-02
• Subjects: Epoxy-silica hybrid material -- Solvent-free sol-gel process -- Silica-based precursor; DABCO 1, 4-Diazabicyclo[2.2.2]octane -- DBTL Dibutylbis[1-oxo(dodecyl)oxy]stannane -- DGEBA Diglycidylether of bisphenol A, D.E.R.™ 332 -- GPTMS (3-Glycidyloxypropyl)trimethoxysilane -- D-230 Polyoxypropylenediamine, Jeffamine™ D-230 -- POSS Polyhedral oligosilsesquixane; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2016.07.053
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: Two types of liquid pre-condensed silica-based precursors bearing epoxy groups were synthesized using the solvent-free sol-gel process of (3-glycidyloxypropyl)trimethoxysilane (GPTMS), in the presence of either basic (DABCO) or neutral (DBTL) catalyst, and further applied for modification of epoxy (DGEBA) – amine (Jeffamine™ D-230) glassy network. The prepared epoxy-silica hybrid materials were characterized by a set of methods including UV–vis, SAXS, TEM, AFM, DMTA, tensile tests, TGA and XRF. All hybrids were optically transparent regardless to the silica-based precursor type and its content showing an improvement mainly in dynamic shear storage modulus in rubbery region (up to 4.3 times), energy to break (up to ∼ 62%), elongation at break (up to ∼ 50%) and thermooxidative stability. The developed procedure is particularly suitable for preparation of fully-transparent massive bulk materials in which the presence of water and volatiles from the sol-gel is highly undesirable. Graphical abstract: Highlights: Glassy epoxy-amine matrix was modified by the highly-condensed silica-based precursors prepared by the solvent-free sol-gel. Obtained hybrids revealed different morphologies dependent on the type of sol-gel catalyst. Improvement in mechanical properties and thermooxidative resistance was achieved for low precursor loadings - 1.8 wt%. All prepared hybrid materials exhibited high optical transparency.