Additives: Silicone-Based Anti-Squeak Additive for Auto Interior Components

A patented silicone-based additive masterbatch newly available from Dow Performance Silicones (previously Dow Corning), Midland, Mich., has been shown to immediately and permanently reduce COF (coefficient of friction) in PC/ABS automotive interior parts to avoid noise in the vehicle cabin. Reportedly the first in a new product family, the Dow Corning HMB-1903 Masterbatch replaces time-consuming, labor-intensive post treatments with felt, lubricants and coatings to improve cost control, design freedom and productivity.   

Dow developed the product to meet emerging trends in electric and autonomous vehicles that are emphasizing the importance of noise minimization in automotive interiors. Noise, vibration, and harshness (NVH) become more noticeable in ultra-quiet electric vehicles, and more intrusive in self-driving cars that will be used for entertainment, relaxation, not just transportation, according to Dow sources. HMB-1903 reportedly delivers high anti-squeak performance that remains stable throughout the useful life of the part. Tests have shown this additive achieves an anti-squeak risk priority number (RPN) rating below 3 at a typical low loading of 4 wt%. A RPN below 3 indicates the material is not squeaking and does not present any risk for long-term squeaking issues.

Moreover, HMB-1903 also achieves an impressively low score for impulse, which represents the number of stick-slip phenomena appearing during the squeaking test. Caused by friction between two surfaces, these phenomena are typically the source of the squeaking noise. The additive has been shown to dramatically reduce the impulse value when compared to pure, non-modified PC/ABS blends. In addition to applications such as instrument panels and center consoles, the new additive can potentially be use for appliance components such as refrigerator bins and trays and transportation applications.