TY - JOUR A1 - Shabir Mahr, Muhammad A1 - Hübert, Thomas A1 - Sabel, Martin A1 - Schartel, Bernhard A1 - Bahr, Horst A1 - Militz, H. T1 - Fire retardancy of sol-gel derived titania wood-inorganic composites N2 - Sol–gel technology was applied in tailoring novel wood-made-inorganic composites with improved thermal and fire properties. In practice, composites materials were prepared by impregnating pine sapwood wood with nano-scaled precursor solutions derived from titanium(IV) isopropoxide followed by a thermal curing process. Thermal and fire properties were evaluated by thermal analysis and cone calorimetry, whereas flammability was specified by oxygen index (LOI) and UL 94 test. Peak heat release rates were moderately reduced indicating fire retardance potential in terms of flame spread attributed to the appropriate protection layer action of the titania-based depositions. LOI (oxygen index) values of these composites were increased up to 38 vol.% in comparison to 23 vol.% for untreated wood. The flame retardancy performance depends on the fire scenario and is strongly influenced by wood loading and crackfree deposition of the titania layers inside the composite. PY - 2012 DO - https://doi.org/10.1007/s10853-012-6628-3 SN - 0022-2461 SN - 1573-4803 VL - 47 IS - 19 SP - 6849 EP - 6861 PB - Springer Science + Business Media B.V. CY - Norwell, Mass. AN - OPUS4-26235 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Shabir Mahr, Muhammad A1 - Hübert, Thomas A1 - Schartel, Bernhard A1 - Bahr, Horst A1 - Sabel, Martin A1 - Militz, H. T1 - Fire retardancy effects in single and double layered sol-gel derived TiO2 and SiO2-wood composites N2 - Sol–gel derived TiO2 and SiO2-wood inorganic composites are prepared by direct vacuum infiltration of silicon and titanium alkoxide based precursors in pine sapwood in one or two cycles followed by a controlled thermal curing process. The resulting flame retardancy effect is investigated under two different fire scenarios using cone calorimetry and oxygen index (LOI). Heat release rates (HRR) especially the values for the second peak, are reduced moderately for all single layered composites. This effect is more pronounced for double layered composites where HRR was reduced up to 40 % showing flame retardancy potential in developing fires. Beside this, smoke release was lowered up to 72 % indicating that these systems had less fire hazards compared to untreated wood, whereas no meaningful improvement is realized in terms of fire load (total heat evolved) and initial HRR increase. However impressively, the LOI of the composites were increased up to 41 vol% in comparison to 23 vol% for untreated wood displaying a remarkable flame retardancy against reaction to a small flame. An approximate linear interdependence among the fire properties and the material loading as well as fire residue was observed. A residual protection layer mechanism is proposed improving the residue properties for the investigated composites. KW - Wood KW - Sol-gel KW - Composite materials KW - Cone calorimeter KW - Fire retardance KW - Flammability PY - 2012 DO - https://doi.org/10.1007/s10971-012-2877-5 SN - 0928-0707 SN - 1573-4846 VL - 64 IS - 2 SP - 452 EP - 464 PB - Kluwer Academic Publ. CY - Dordrecht AN - OPUS4-27618 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -