Solid-liquid interfacial energy of neopentylglycol.

The grain boundary groove shapes for equilibrated solid neopentylglycol (2,2-dimethyl-1,3-propanediol) (NPG) with its melt were directly observed by using a horizontal temperature gradient stage. From the observed grain boundary groove shapes, the Gibbs-Thomson coefficient (Gamma), solid-liquid interfacial energy (sigma(SL)), and grain boundary energy (sigma(gb)) of NPG have been determined to be (7.4+/-0.7)x10(-8) Km, (7.9+/-1.2)x10(-3) Jm(-2), and (15.4+/-2.5)x10(-3) Jm(-2), respectively. The ratio of thermal conductivity of equilibrated liquid phase to solid phase for the NPG has also been measured to be 1.07 at the melting temperature.