Year: 2021
Type: dissertation
Abstract: The aim of this thesis was to develop a thermal insulation coating using acrylate copolymer binders with functional thermal insulation fillers and test different properties of prepared coatings. Coatings were developed for thermal insulation, cool roof and safe touch applications. Research methods used in the thesis were literature review and laboratory experiments. \n \nThermal insulation coatings have been available since 1960’s. NASA started developing these coatings for keeping very cold fuels cool and in liquid form in storage tanks. Thermal insulation coating blocks heat transfer with functional fillers which have nanosized pores filled with gas, usually air in them. These pores block heat by exploiting Knudsen effect because the pore size is smaller than the mean free path of the gas molecules. \n \nCool roof paints are also thermal insulation coatings. The main idea of these coatings is to keep heat from sun away from buildings by applying cool roof coating on ceilings and walls of buildings. Cool roof coating will reflect and emit the heat coming from the sun. \n \nOther properties of thermal insulation coatings include for example anti-condensation properties which come from keeping wall temperature closer to the ambient temperature thus minimizing condensation. Sound reduction and reduction of corrosion under insulation is also possible with these types of coatings. \n \nRaw materials included few different acrylate copolymers. Among tested binders were high solid acrylate dispersion, styrene acrylic emulsion, acrylate polyurethane dispersion and siloxane emulsion. Fillers used in this thesis were three different aerogels, two different microspheres, micro crystalline cellulose, and magnesium hydroxide. \n \nExperimental part included mechanical testing, thermal conductivity and effusivity measurements, measuring of solar reflectance index and differential scanning calorimetry testing for glass transition temperatures. \n \nResults were promising with quite simplified recipes. Best self-prepared coating sample had thermal conductivity of 0,061 W/m*K. For safe touch application effusivity value of 140,9 W*s0.5/(m2*K) was reached. Best cool roof coating had SRI value of 106 W/m2*K.
Source: Aaltodoc (Aalto University)
Author: Matti Laasonen
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W3154280452