American Coatings Show 2018

Sessions Speakers Exhibitors Products Press Releases Show Specials Floor Plan Buzz

9.1 Hollow Thermoplastic Microspheres in Elastomeric Cool Roof Coatings (Room 243-245)

Hollow ultra low density thermoplastic microspheres can be used as filler in elastomeric waterproof coatings to improve a number of important properties of the coatings. Hollow microspheres help reflect solar radiation and reduce the temperature of the coating. The mechanism for the reflection is described in this paper and is compared with the mechanism for reflection by pigment particles like TiO2. Results from solar reflection measurements show that the microsphere filled coating system reflects solar radiation of all incoming wavelengths, which is different from the way TiO2 reflects light. The number of reflecting units is still important for the total solar reflection, and suggests that the average size of the microspheres should be as little as possible. Like most other filler, hollow low density microspheres can be used in combination with pigments. Another important property of elastomeric roof coatings is the elasticity. When inorganic fillers are exchanged for resilient thermoplastic hollow microspheres, the elasticity is improved. The softer character of the coating is good but inherently these types of soft coatings face a challenge regarding dirt pick-up resistence. This paper presents new scientific data showing that high elasticity can be combined with dirt pick-up resistance in a cost efficient manner. Without sacrifying total solar reflectance! The paper will elaborate on the mechanisms of this new, high performing system.