The goal of this thesis was to investigate new, innovative, natural, eco friendly and inexpensive insulation material which can be used for insulating different types of buildings. In this thesis preparation and testing of insulation boards which are made of two fundamental components are presented. The main compononts are: dry corn stalk piths and gypsum. The idea was, that corn stalks which often end up as a waste product of food industry, can be used as bio-insulative material. Gypsum is also of a natural origin or it is obtained as a byproduct in flue gas desulfurization, and it acts in our case as a binder. Gypsum as a binder holds the corn stalk particles together as they are shaped into insulating boards.
For verification of insulative properties, we made 16 different samples. The variations were made with different volume quantities of corn fractions in mixture and different sizes of the defined fractions. For the prepared specimens conducted experiments were performed to evaluate thermal conductivity. For the most promising mixtures regarding their thermal conductivity, additional samples were made, which have been further tested for the obtainment of mechanical properties of material. Additional tests were conducted to check water absorption of corn stalk piths. We have also checked how the volume of stalk piths change due to absorbtion of water.
Results for thermal conductivity range between the values of ?=0.38 W/mK for mixture that contained 10 % corn stalk particles, down to ?=0.1 W/mK for mixture that contained 70 % of corn stalk particles. Average compression strength is 1.27 N/mm^2, average flexural strength is 1.54 N/mm^2. Testing for water absorption showed us that corn absorbs enormous quantities of water. Results show that boards like those have significantly smaller thermal conductivity than gypsum, but still do not have needed thermal properties to be accounted as an insulation material.
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