Comprehensive Analysis of the Effect of Polyisobutyl-ene (PIB) Molecular Weight on Damping Properties of Butyl-Based Constrained Layer Damping Systems

This paper investigates the effects of combining high molecular weight polyisobutylene (HMW PIB) and low molecular weight polyisobutylene (LMW PIB) on the performance of butyl-based constrained layer damping (CLD) systems. By formulating a series of PIB blends, this study exam-ines how different combinations of HMW and LMW PIB influence critical mechanical and damp-ing properties for noise, vibration, and harshness (NVH) applications. The results reveal that higher proportions of HMW PIB significantly enhance mechanical and adhesion strength, while increased LMW PIB weight percentage leads to improved damping behaviour, resulting in superior energy dissipation and damping efficiency. Notably, Sample A demonstrates a balanced performance with commendable mechanical integrity and effective damping capabilities. In contrast, Sample B excels in damping properties due to its higher LMW PIB weight percentage, making it ideal for applica-tions requiring optimal NVH control, while Sample C, with its robust mechanical characteristics, shows weaker damping efficiency. This research provides valuable insights for the design and ap-plication of advanced damping materials, highlighting the importance of optimizing the combina-tion of HMW and LMW PIB to develop high-performance solutions in the automotive, aerospace, and construction industries, where effective vibration control is essential.

Keywords:

Constrained Layer Damping , Butyl Rubber , Polyisobutylene , Noise Vibration Harsh-ness.