Due to their tendency to hydrolyze rapidly, vinyl silanes such as Dynasylan® VTMO are used as drying agents in moisture-curing hybrid-sealing compounds.
Dynasylan® VTMO reacts with unwanted water, even when other silanes are present due to the formulation for other purposes (e.g. adhesion promotion). Thus Dynasylan® VTMO gives sealing compounds improved storage stability and prevents the compound from curing prematurely.
The main source of unwanted moisture penetration in hybrid systems is, beside insufficient moisture exclusion during production, often leftover of residual moisture on the filler material.
Where further requirements on the drying agent due to the end application are needed, e.g. high flash point and low volatility, Dynasylan® 6490 as oligomeric and environmentally friendly drying agent is recommended.