Effect of crosslink density on Sealant Properties Based on Silane- Modified Polyurethane

This study investigates the profound influence of crosslink density, stemming from both primary and secondary aminosilanes, on the properties of one-part polyurethane sealants. Through systematic experimentation, we elucidate the consequential effects of varying crosslinking agents on mechanical, thermal, and adhesive characteristics. Our results highlight the distinct impact of primary and secondary aminosilanes on the resulting material, offering valuable insights into tailoring specific properties for diverse applications. The chemical and physical structures of the one-part polyurethane sealants were investigated by nuclear magnetic resonance spectroscopy (NMR), Fourier transform infrared spectroscopy (FT-IR) and the mechanical properties were evaluated by tensile tests. The results reveal that silane-terminated moisture-curable polyurethanes can be successfully synthesized and cured with Dibutyltin Dilaurate catalysts. The comparative analysis underscores the nuanced interplay between crosslink density and material performance, paving the way for optimized formulations. This research enhances the fundamental understanding of crosslinking mechanisms, guiding the formulation of materials suitable for a wide array of applications.