Improvement of fire reaction and mould growth resistance of a new bio-based thermal insulation material

Abstract

In the present paper, the performance of an innovative thermal insulation rigid board is evaluated in terms of fire behaviour and fungal resistance. The board is based on vegetal pith and a natural gum (corn pith and sodium alginate) and it is completely compostable. This new composite was developed in previous work. Here boric acid, aluminium hydroxide and ammonium polyphosphate are used as fire retardants and montan wax, acetic acid and lactic acid are used as water repellent and fungicides respectively. Interactions between these different treatments is investigated. Both flaming and smouldering combustion processes of the different formulations are evaluated by small-scale techniques which include pyrolysis microcalorimetry and thermogravimetric analysis. A medium-scale device is also designed in order to study the impact of the different additives to the smouldering kinetics. Fire behaviour tests show that good improvement is obtained, both in flaming and smouldering combustion when boric acid is added. Although smouldering is not avoided in any case, the addition of 8% of boric acid or aluminium hydroxide slows down the speed of combustion propagation. The effect of the different additives on the moisture content and mould growth at 97% RH and 27ºC is analysed. Under such severe conditions none of the additives is able to prevent mould growth, with the exception of boric acid. None or marginal mould growth was observed on samples containing 8% of boric acid although moisture content was higher than the other cases.

Flame Retardancy of Wood Fiber Materials Using Phosphorus-Modified Wheat Starch

“…This peak is usually rarely observed in cellulosic biomass. While wood is richer in lignin, it may be due to the decomposition of lignin [58,59]. There is no great difference between the HRR of starch-based FR except for the cleaned variant of WS-K which exhibits worse performances with high pHRR, high THR, and the lowest residue from all FR samples.…”

Sustainable thermal insulation biocomposites from rice husk, wheat husk, wood fibers and textile waste fibers: Elaboration and performances evaluation

“…Various binders were explored in literature to bind renewable resources such as sugarcane bagasse (Guna et al, 2019), miscanthus fiber (Eschenhagen et al, 2019), sunflower stalk fiber (Eschenhagen et al, 2019), wood fibers/textile fibers (Lacoste et al, 2018), coffee chaff T (Buratti et al, 2018), stubble fibres (Binici et al, 2014), corn stalk (Palumbo et al, 2017), rice straw (Wei et al, 2015a, b), rice husk (Chabannes et al, 2014), and food crop by-products (Palumbo et al, 2015). For instance, alginate, starch and tannin resin have been used as biobased binders for composites manufacture from agricultural crop byproduct composites, larch bark, and wood fibers/textile waste (Kain et al, 2014;Lacoste et al, 2018;Palumbo et al, 2017). The wood fiber/ textile waste based composites with alginate binder could be considered for building materials because they possess sufficient thermal conductivity (0.078-0.089 W/m/K), density (308-333 kg/m 3 ), flexural strength (0.84 MPa), and compressive strength (0.44 MPa) (Lacoste et al, 2018).…”

Improvement of Water Resistance of Hemp Woody Substrates through Deposition of Functionalized Silica Hydrophobic Coating, While Retaining Excellent Moisture Buffering Properties

“…derivatives (Lazko et al 2013) are still widely used to treat cellulose materials despite their probable harm. Palumbo et al (2017) also used boric acid to both delay mould growth, and limit the extent of combustion of corn pith insulation panels.…”