Permeability of coatings for water and water vapor is an important factor in their wood protective function.In this study,the permeability of coatings in terms of liquid water and water vapor absorption and desorption...Permeability of coatings for water and water vapor is an important factor in their wood protective function.In this study,the permeability of coatings in terms of liquid water and water vapor absorption and desorption was measured based on different parts of the standard EN 927.This study evaluated the permeability of commercial coating systems and ascertained effects of coating layering on the coating permeabil-ity.For this measurement,six different waterborne acrylate dispersions were used as paint on spruce test samples.The results clearly revealed that liquid water and water vapor uptake were affected by coating film thickness,number of coats,and coating composition(producer).It was ascertained that the type of coating pigmentation affected water absorption of coatings and that with a constant coating film thickness,the number of coats affected water vapor absorption and desorption,but not water absorption.Furthermore,it was observed that the number of coats affected the cor-relation between the coating film thickness and water vapor absorption and desorp-tion.The values for water vapor absorption were much higher than for liquid water absorption and,unlike the water vapor absorption rate,the water vapor desorption rate was approximately 50%lower.展开更多
基金funded by Czech University of Life Sciences Prague,project no.CIGA 20174304.
文摘Permeability of coatings for water and water vapor is an important factor in their wood protective function.In this study,the permeability of coatings in terms of liquid water and water vapor absorption and desorption was measured based on different parts of the standard EN 927.This study evaluated the permeability of commercial coating systems and ascertained effects of coating layering on the coating permeabil-ity.For this measurement,six different waterborne acrylate dispersions were used as paint on spruce test samples.The results clearly revealed that liquid water and water vapor uptake were affected by coating film thickness,number of coats,and coating composition(producer).It was ascertained that the type of coating pigmentation affected water absorption of coatings and that with a constant coating film thickness,the number of coats affected water vapor absorption and desorption,but not water absorption.Furthermore,it was observed that the number of coats affected the cor-relation between the coating film thickness and water vapor absorption and desorp-tion.The values for water vapor absorption were much higher than for liquid water absorption and,unlike the water vapor absorption rate,the water vapor desorption rate was approximately 50%lower.
