Advanced Physical Research

In this study, a novel polyurethane (PU) based composition was developed for the first time, characterized by the incorporation of a minimal amount of additives (0.05 wt%), which significantly enhanced the mechanical properties and structural compatibility with high-density polyethylene (HDPE). The effect of the inorganic additive boron nitride (BN) on the physico-mechanical properties and structural behavior of PU was investigated under various external influences, including temperature, electrical discharges, and mechanical stress. The concentration of BN in the PU composition ranged from 0.01 to 0.1 wt%. The results demonstrated that a BN content of 0.05 wt% in the PU matrix was optimal, leading to an approximately 15% increase in the mechanical strength of the resulting film. Experimental findings indicate that this enhancement in strength is associated with changes in the supramolecular structure of the material. While the activation energy of mechanical stress (U) and its intrinsic value (U₀) remained unchanged for both unmodified and BN-modified PU, the addition of BN at the optimal concentration altered the structural sensitivity coefficient (α). This modification reflects a shift in the structural responsiveness of the polymer and a corresponding improvement in mechanical strength (σ).