Bifunctional Hairy Silica Nanoparticles

Bifunctional hairy silica nanoparticles are silica nanoparticles covered with alkyl and amino organic chains (24). These nanoparticles were prepared as high performance additives for lubricants. 

In comparison to hairy silica nanoparticles covered only with a single t5rpe of an organic chain, binary hairy silica nanoparticles exhibit the advantage of both types of organic chains, which show an excellent compatibility with lubricants and adsorption behavior to metal surfaces. 

Nanoparticles with different ratios of amino and alkyl ligands were investigated. In comparison to an untreated lubricant, bifunctional hairy silica nanoparticles reduce the friction coefficient and wear scar diameter by 40% and 60%, respectively. The wear mechanism of bifunctional hairy silica nanoparticles was investigated. The protective and filling effect of the nanoparticles was improved because of a collaboration of the amino and the alkyl ligands (24). 

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