Using Rheometry to predict liquid adhesive "processa

A controlled stress rheometer with normal force measurement capability was used to screen a series of liquid pressure sensitive adhesives. The samples were processed in a roll coating application with a pattern bar producing controlled bands of the final coating. Some samples coated well, but others produced surface irregularities such as ribbing or beading and were considered to have failed. Conventional viscometry could not predict which samples were likely to perform well and which were likely to fail. The use of rheometry proved more successful and by calculating certain dimensionless groups, the samples could be ranked in order of suitability. Surface tension information proved to be less relevant than overall viscoelastic data as provided by measurement of normal stress in the fluid under steady simple shear. ARES-G2 高级流变拓展系统/旋转流变仪