Synthesis & characterization of novel silicone dendrimers as base stock for high performance lubricants

• Novel silicone core ester functional dendrimers were synthesized in high yield.
• Speier's catalyst in hydrosilation reaction is used in the synthesis.
• Esterification reactions using stannous oxide as catalyst were carried out to achieve complete neutral catalyst.
• High flash point and low pour point silicone ester dendrimers.

The silicone core GI dendrimers having terminal Si-H groups reacted with maleic anhydride in presence of Speier's catalyst to afford anhydride terminated dendrimers. These anhydride dendrimers were further reacted with long chain aliphatic alcohols in presence of lower valent tin oxide as catalyst to synthesize novel second generation complete neutral silicone ester dendrimers. These high performance silicone esters dendrimers can be used for different avionic applications and also as base stock material for lubricants. Characterizations of the dendrimers were carried out by elemental analysis; Fourier transforms infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance spectroscopy (1H NMR spectroscopy). Physical properties like density, viscosity, flash point and pour point of the dendrimers were also studied. Vapor pressure osmometery (VPO) and gel permeation chromatography (GPC) were used for measuring the molecular weight and molecular weight distribution of the dendrimers.

Several silicone core second generation (GII) ester terminal dendrimers were synthesized by using hydrosilylation, sol–gel hydrolysis and esterification reactions subsequently. These high performance silicone esters can be used for different avionic applications and also as base stock material for lubricants. Characterizations of the product were carried out by elemental analysis; Fourier transforms infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance spectroscopy (1H NMR spectroscopy). Physical properties like density, viscosity, flash point and pour point of silicone esters dendrimers were also studied. Vapor pressure osmometery (VPO) was used for measuring the molecular weight of the dendrimers.Figure optionsDownload as PowerPoint slide