Embed Size (px)
Citation preview
Final COST FP1006 meeting “Advances in modified and functional bio-‐based surfaces” at the Aristotle University of Thessaloniki, Thessaloniki, Greece, 7-‐9 April 2015
Sabrina Palanti1, Elisabetta Feci 1, Giovanni Predieri2 , Laura Bergamonti 2 1 CNR – IVALSA Istituto per la Valorizzazione del Legno e delle Specie Via Madonna del Piano 10 I – 50019 Sesto Fiorentino (FI) 2 Dipartimento di Chimica G.I.A.F., Università di Parma, Parco Area delle Scienze I -‐ 43100 Parma
Polyamidoamines (PAAs) are hybrid –organic polymers obtained by the reaction between N,N-methyl-bis-acrylamide (MBA) and Ethanolamine (EtA).
PAAs can be functionalized with siloxane, e.g. aminopropyltriethoxysilane (APTES), through hydrolysis and condensation reaction (sol-gel process),
Reagents: N, N-‐methyl-‐bis-‐acrylamide (MBA) Ethanolamine (EtA) Aminopropyltriethoxysilane (APTES). Solvent, water: ethanol 30:70 Formulations: Formulation A, MBA : EtA molar ratio 1:1 Formulation B, MBA : APTES molar ratio 1:1 Formulation C, MBA : EtA : APTES, molar ratio 1: 0,5: 0,5
Preparation: The reagents of respective formulations were dissolved in solvent and then maintained under stirring until that the suspension became clear.
The research has been developed on two levels:
1. Mini-block test against fungus C. puteana of different combinations between the 3 reagents.
2. EN 113 test of the most promising formulations against three different fungi, C. puteana, C. versicolor and P. placenta
The research was supported by RENNER spa, Minerbio, Bologna (IT)
L. Bergamonti, E. Chiappini, G. Predieri, S. Palanti, L. Maistrello, “Wood preservative composition” Int. Patent application WO 2015/004590 A1.
The impregnation process was characterized through the determination of Weight Per cent Gain (WPG1) referred to the anhydrous mass of untreated wood: WPG1 = [(Mt– M0)/ M0] x100
M0 =dry mass untreated wood and Mt=dry masses of treated wood
Wood specimens were subjected to the leaching procedure according to EN 84 (1997).
WPG2 = [(Ml– M0)/ M0] x 100
LF ( Leached Formulation) = [(Mt – Ml)/(Mt-‐ M0) x 100
M0 =dry mass untreated wood and Ml =dry masses of treated leached wood
Duration of test : 8 weeks Fungus: C. puteana Mini-‐block test: Kolle flask, in each one 4 treated and 2 reference controls.
Characterization of impregnations and results
Dimension of wood mini-‐blocks: 30 x 10 x 5 mm3
Wood samples dimension: 5 x 1,5 x2,5 cm3
Duration of test : 16 weeks Fungus: C. puteana, P. placenta, T.versicolor EN 113 test: Kolle flask, in each one treated and one reference control.
Characterization of impregnations
Results
• The formulations based on PAAs showed a slight efficacy, with respect to untreated controls, against basidiomycetes fungi, principally when APTES, alone or combined with EtA, was included into formulation.
• The most important factor for the fixation of PAAs to the wood was the functionalization with siloxane and probably the formation of bridges C-‐O-‐Si obtained by the condensation of silanols (Vignali et al., 2011.)
• The hypothetical mechanism of action was the establishment into the impregnated wood of unfavourable conditions for fungal growth due to the high pH value.
Vignali F., Predieri G., Feci E., Palanti S., Baratto M.C., Basosi R., Callone E., Müller K. (2011). “Interpenetration of wood with NH2R-‐functionalized silica xerogels anchoring copper(II) for preservation purposes” Journal of Sol-‐Gel Science and Technology. Volume 60, Issue 3, December 2011, Pages 445-‐456
![Depczynska - Commercial biobased woodcost-fp1006.fh-salzburg.ac.at/fileadmin/...biobased... · Bioresource Technology 99, 1300–1304. [17] Prashantha, M.A.B. (2007). Synthesis and](https://img.pdfslide.net/doc/110x75/5f3e0b49058e1d068e5fff05/depczynska-commercial-biobased-woodcost-bioresource-technology-99-1300a1304.jpg)
