Polymeric Self-Assembled Monolayers. 4. Chemical, Electrochemical, and Thermal Stability of ω-Functionalized, Self-Assembled Diacetylenic and Polydiacetylenic Monolayers

Here we contrast the stability of monomeric and photopolymerized self-assembled monolayers (SAMs) containing a diacetylene group (HS(CH 2 ) 10 C⋮CC⋮C(CH 2 ) 10 COOH) with SAMs prepared from simple n -alkanethiols. The polymerized SAMs are extremely durable compared to either the n -alkanethiol SAMs or the unpolymerized diacetylenic SAMs. For example, they are stable to repeated electrochemical cycling to extreme potentials, thermal excursions to 200 °C, and exposure to hot base (1:1 mixture of ethanol and 1.0 M aqueous KOH at 100 °C). All of these conditions completely strip n -alkanethiol SAMs from Au substrates. These high-performance materials are suitable for applications in lubrication, adhesion, corrosion passivation, and chemical sensing.