Development and performance evaluation of a hemp–starch composite

Abstract

This article describes the results of a research project carried out at the University of Reims Champagne-Ardenne. The aim of this article is to develop a new insulating material produced by bonding hemp shives with wheat starch as a binder and to characterize its physical properties such as sorption isotherm, water vapour permeability, thermal conductivity, heat capacity and porosity. The equations of coupled heat and moisture transfer within the panels are introduced. These governing equations are applied on the room level in order to assess the hygrothermal behaviour of the panels and its impact on energy consumption and indoor comfort. Simulations are performed for Nancy (France) winter conditions with the simulation environment Simulation Problem Analysis and Research Kernel (SPARK) suited for complex problems.

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

“…Potato starch ( Figure 3 a) has a high polymerization degree, which gives a viscous binder and provides a good mechanical property for the S-BP composite. Starch was used as a binder to make several bio-composites, such as hemp–starch and palm date fibers-starch [ 8 , 10 , 11 , 33 ]. It can stick the particles together and ensure the transmission of shear forces between the fibers.…”

“…The porosity and pore structure of the composite was measured using mercury intrusion porosimetry (MIP) using a 140 series Pascal Thermo Scientific Porosimeter (France Scientifique, Saint Genis Laval, France) [ 10 , 34 ]. The pore access diameter ranged from 3.8 μm to 1000 μm.…”

“…The sorption isotherm tests were carried out in accordance with NF EN ISO standard 12572 (2001) [ 2 , 10 ]. They allow plot the sorption curve representing the variation of the water content as a function of relative humidity of ambient air at a constant temperature of 23 °C.…”

“…Several studies have been already published on the use of crop by-products for buildings such as wheat straw, which was used in sustainable building [ 7 ]. Hemp concrete is the most studied among different composite materials [ 8 , 9 , 10 , 11 , 12 ]. Hemp–starch composite presents a porous structure providing a good thermal insulation with a thermal conductivity ranging from 0.06 W·m −1 ·K −1 to 0.1 W·m −1 ·K −1 .…”

Hygric behaviour of a clay-Typha bio-based material for building

“…Bio-based composites are becoming more and more used as thermal insulating material for reducing building energy consumption due to their interesting technical performances [1][2][3][4]. Many investigations have been conducted to study their hygric behaviour , as for instance, the moisture buffering value (MBV) of a new agromaterial based on hemp and starch [3]. Results show that such materials are considered as excellent humidity regulator (MBV of 3.39 g m -2 %RH -1 ).…”