Hygrothermal and Acoustical Performance of Starch-Beet Pulp Composites for Building Thermal Insulation

Abstract

This article deals with the elaboration and the characterization of an innovative 100% plant-based green composite made solely of beet pulp (BP) and potato starch (S). Using this type of material in insulation applications seems a good solution to reduce the CO2 gas emissions in building. The influence of the starch amount on composite characteristics was studied. Four mixtures were considered with different S/BP mass ratios (0.1, 0.2, 0.3 and 0.4). The physical properties of these materials were studied in terms of porosity, apparent and absolute densities, thermal conductivity, and hygric properties. The influence of humidity content on acoustical properties was studied as a function of frequency. Test results show a real impact of both starch and humidity contents on the hygrothermal and acoustical properties of the studied material due to the porosity. The composite with the lowest amount of starch (S/BP = 0.1) seems to be the optimal composition in terms of the hygrothermal and acoustical behaviors.

Hygric Behavior of Viticulture By-Product Composites for Building Insulation

“…The water vapor permeability, δ v , was between 1.40 × 10 −11 kg•m −1 •s −1 •Pa −1 for the stalk composite (A/S) and 1.79 × 10 −11 kg•m −1 •s −1 •Pa −1 for the grape pomace composite (A/GP). The values obtained in this study are intermediate between the hemp/starch (H/S) composite [17] and the beet pulp/starch composites (BP/S) [18]. In comparison to the composite with the same polymer matrix (starch), the water vapor diffusion resistance factor µ is 25.7 and the water vapor permeability is 0.78 × 10 −11 kg•m −1 •s −1 •Pa −1 for BP/S, while for H/S, δ v is equal to 4.74 × 10 −11 kg•m −1 •s −1 •Pa −1 , and µ is 4.22.…”

“…As starch is very hydrophilic, it behaves similar to a sponge and is capable of absorbing water from the ambient atmosphere [23], making starch-based materials highly hygroscopic. For example, beet pulp/starch materials [18] adsorb up to 20% of water and hemp/starch materials [24] adsorb up to 17% of water at 93% relative humidity. Under very high relative humidity (93% RH) and at room temperature (20 • C), the degradation of the composite and the development of fungi on its surface are observed.…”

Monitoring of Thermal and Moisture Processes in Various Types of External Historical Walls

“…Problems related to heat loss and the dampening of building partitions have always accompanied construction and in the most recent literature can be found in many works on this subject, e.g., regarding internal thermal insulation [1][2][3][4], thermal insulation of historical buildings [5][6][7][8], and even innovative insulation materials, 100% plant-based, allowing for the reduction of CO 2 emissions in construction [9].…”

Experimental characterization of starch/beet-pulp bricks for building applications: Drying kinetics and mechanical behavior

“…A review of the literature shows a whole range of plant aggregate based materials (Mnasri et al 2020): hemp concrete, cork and straw based products (Douzane et al 2016), wood, crop based materials such as typha-Australis (Niang et al 2018), date palm fibers and beet-pulp fibers (Belakroum et al 2017) … Recent studies describe the elaboration and characterization of a new agro-composite based on sugar beet pulp and potato starch as a bio-sourced binder (Karaky et al 2018). Different compositions (ratio of starch/pulp) designed for building thermal insulation are tested.…”