College of Education for Pure Sciences, Kirkuk University discussed a master dissertation on the surface density extraction of polymers (PMMA and PS) via using positronium annihilation spectroscopy and the hole theory of surface gradient. by postgraduate student, Ms. Sarah Qusay Abdullah.
The dissertation aimed at studying the density distribution of some polymers as a function of the thickness of the interface and understanding the depth of penetration of polymers with various molecular weights.
The dissertation concluded that raising the temperature leads to deeper penetration and an increase in the thickness of the interface, meaning that raising the temperature will increase the number of gaps generated between molecules and reduce the energy gradient coefficient and thus changes in temperature lead to a change in the structure of the polymer.