Study on covering power of micro-nanoscale calcium silicate
The use of natural mineral powders as functional materials is a characteristic path to achieve high-value and sus-tainable development of inorganic mineral powders.Among them,micro-nanoscale calcium silicate obtained through fine grinding and controllable wind selection classification is a highly valuable powder functional material.The influence of micro-nanoscale calcium silicate on the covering power,thermal oxygen aging capability and other properties of coating films and PVC composite films was mainly investigated.The washability tester and reflectivity tester were used to test the washability&stain resistance,and ratio of building coatings.Furthermore,the whiteness,mechanical properties,and ther-mal oxygen aging resistance of PVC composite films with added micro-nanoscale calcium silicate were studied by using au-tomatic whiteness tester,universal mechanical testing machines and thermal oxygen aging testing chamber.The research re-sults showed that the introduction of micro-nanoscale calcium silicate could not only improve the stain resistance of coating films by 22.2%,but also could greatly enhance the contrast ratio of coating films with 32.7%.The whiteness of composite films could be enhanced to some extent by 2.0%.At the same time,the tensile strength of composite films was increased by 9.6%,and corresponding thermal oxidative aging resistance was also improved.It could be found that the ultra-fine,high whiteness,and excellent heat resistance stability of micro-nanoscale calcium silicate were the key factors to improve the covering power and thermal oxygen aging capability of coating films and PVC composite films.