Rate-Dependent Adhesion between Opposed Perfluoropoly(alkyl ether) Layers: Dependence on Chain-End Functionality and Chain Length

Rate-Dependent Adhesion between Opposed Perfluoropoly(alkyl ether) Layers: Dependence on Chain-End Functionality and Chain Length

Adhesion was measured repeatedly between opposed molecularly thin layers of perfluoropoly(alkyl ether)s on mica, with particular attention to the dependence of the adhesion on chain-end functionality and chain length of the polymer. The polymer layers were kept in contact for specified times that differed by 4 orders of magnitude (0.01-500 s) and then unloaded (separated) at rates that varied b...

Tribology of Confined Fomblin-Z Perfluoropolyalkyl Ethers: Role of Chain-End Chemical Functionality

Strong dependence of the tribological response upon the nature of the polar end groups of perfluorinated linear chains was observed for Fomblin-Z perfluoropolyalkyl ethers of similar length and composition but terminated by a different polar group at both chain ends. The number-average molecular weight of the polymers was Mn ≈ 2000 g mol-1 and the chain-end functionality was either carboxylic a...

Important factors for silane adhesion promoter efficacy: surface coverage, functionality and chain length

The effects of an ammonia-based catalyst, surface coverage, organofunctional group and chain length on silane adhesion promoter efficacy were examined at a benzocyclobutene (BCB)/silicon dioxide interface with silanes of varying functionality and chain length. Fracture-mechanics-based techniques, and X-ray photoelectron spectroscopy and contact-angle measurements were used to quantify the adhes...

Relative Entropy Rate between a Markov Chain and Its Corresponding Hidden Markov Chain

 In this paper we study the relative entropy rate between a homogeneous Markov chain and a hidden Markov chain defined by observing the output of a discrete stochastic channel whose input is the finite state space homogeneous stationary Markov chain. For this purpose, we obtain the relative entropy between two finite subsequences of above mentioned chains with the help of the definition of...

pH and Substrate Chain Length Dependence of the Activity of "Short-Chain"-, "Medium-Chain"- and "Long-Chain" -Acyl-CoA Dehydrogenase