Influence of cohesive forces on the glass transition temperatures of polymers

The relationship between cohesive energy (c.e.) or cohesive energy density (c.e.d.) and the glass transition tenperature ( T g ) of polymers has been re‐examined on the basis of literature data. For polymers with T g above 25°C., there is no correlation between published or calculated values of c.e. or c.e.d. and T g . However, for the rest of the polymers there is a linear relationship between c.e.d. and T g , and a broad relationship between c.e. and T g . These results imply that c.e.d. is the regulating, though not the only, factor in determining T g 's up to values of approximately 25°C.