Silicones

Siloxane-Based Silane Reducing Agent Organosilanes are hydrocarbon-like and possess the ability to serve as both ionic and free-radical reducing agents. These reagents and their reaction by-products are safer and more easily handled and disposed than many other reducing agents. The metallic nature of silicon and its low electronegativity relative to hydrogen lead to polarization of the Si-H bond yielding a hydridic hydrogen and a milder reducing agent compared to aluminum-, boron-, and other metal-based hydrides. A summary of some key silane reductions are presented in Table 1 of the Silicon-Based Reducing Agents brochure. Pendant Functional Fluid; MethylHydrosiloxane-Dimethylsiloxane Copolymer, TMS Terminated MethylHydrosiloxane copolymers are the primary cross linkers for 2-part vinyl-addition silicones and intermediates for functional copolymers. Hydrogen dimethicone; Dimethylhydropolysiloxane; Dimethicone/methicone copolymer; Polysiloxanes dimethyl methyl hydrogen, Hydride functional polydimethylsiloxane; Siloxanes and silicones, dimethyl, methyl hydrogen Viscosity: 110-150 cStMolecular Weight: 5,500-6,500 g/molMol% Hydride: 7-9Potential reducing agents in the mode of HMS-991 or HMS-997Extensive review of silicon based reducing agents: Larson, G.; Fry, J. L. "Ionic and Organometallic-Catalyzed Organosilane Reductions", Wipf, P., Ed.; Wiley, 2007

MCR-V25: monoVinyl Terminated Polydimethylsiloxane (Monofunctional Fluid) Mono-vinyl functional PDMS macromers are monodisperse (low PDI) fluids that can be used as components in silicone gels and modifiers in release coatings. MCR-V25 Properties Viscosity: 400-600 cStMolecular Weight: 15,000-20,000 g/molRefractive Index: 1.403

PDV-0541: Vinyl Terminated Diphenylsiloxane-Dimethylsiloxane Copolymer (Telechelic Functional Fluid) These fluids are most often employed in 2-part addition cure silicone elastomers where special thermal or optical properties are required. PDV-0541 Properties Viscosity: 10,000 cStMolecular Weight: 60,000 g/molVinyl (eq/kg): 0.027-0.038Refractive Index: 1.430

DMS-S42: Silanol Terminated PDMS, 18,000 cSt (Telechelic Functional Fluid) Terminal silanol groups render polydimethylsiloxanes susceptible to condensation under both mild acid and base conditions. They are intermediates for most room temperature vulcanizeable (RTV) condensation cure silicones. The reactivity of silanol fluids is utilized in applications other than RTVs. Low viscosity silanol fluids are employed as filler treatments and structure control additives in silicone rubber compounding. Intermediate viscosity (1,000-10,000 cSt) fluids can be applied to textiles as durable fabric softeners. High viscosity silanol terminated fluids form the matrix component in tackifiers and pressure sensitive adhesives. DMS-S42 Properties Viscosity: 18,000 cStMolecular Weight: 77,000 g/molWt.% OH: 0.4OH (eq/kg): 0.023-0.025

Thermal Silicone Fluid High phenyl content fluids are utilized as heat-exchange fluids, dielectric coolants, impregnants for sintered metal bearing, and base oils for high temperature fluids. Low phenyl content fluids are utilized at lower temperatures than high phenylsilicones and find extended temperature service applications as lubricating oils for critical devices such as timers and systems involving rubber, plastic and aluminum mating surfaces. 1,1,5,5-Tetraphenyl-1,3,3,5-tetramethyltrisiloxane PhenylMethylsiloxane Oligomers - Diffusion FluidsViscosity, 25 °C: 35-40 cStViscosity, 99 °C:Pour-point, °C: -35Specific gravity: 1.07Refractive index: 1.556Surface tension: 37.3Molecular Weight: 485 g/mol

DMS-H05: Hydride Terminated PDMS, 4-6 cSt (Telechelic Functional Fluid) Hydride terminated silicones are chain extenders for vinyl-addition silicones, enabling low-viscosity, high elongation formulations. They are also intermediates for functionally terminated silicones. DMS-H05 Properties Viscosity: 4-6 cStMolecular Weight: 600-700 g/molWt.% Hydride: 0.3

Siloxane-Based Silane Reducing Agent Organosilanes are hydrocarbon-like and possess the ability to serve as both ionic and free-radical reducing agents. These reagents and their reaction by-products are safer and more easily handled and disposed than many other reducing agents. The metallic nature of silicon and its low electronegativity relative to hydrogen lead to polarization of the Si-H bond yielding a hydridic hydrogen and a milder reducing agent compared to aluminum-, boron-, and other metal-based hydrides. A summary of some key silane reductions are presented in Table 1 of the Silicon-Based Reducing Agents brochure. Pendant Functional Fluid; MethylHydrosiloxane-Dimethylsiloxane Copolymer, TMS Terminated MethylHydrosiloxane copolymers are the primary cross linkers for 2-part vinyl-addition silicones and intermediates for functional copolymers. Hydrogen dimethicone; Dimethylhydropolysiloxane; Dimethicone/methicone copolymer; Polysiloxanes dimethyl methyl hydrogen, Hydride functional polydimethylsiloxane; Siloxanes and silicones, dimethyl, methyl hydrogen Viscosity: 25-35 cStMolecular Weight: 1,900-2,000 g/molMol% Hydride: 15-18Potential reducing agents in the mode of HMS-991 or HMS-998Extensive review of silicon based reducing agents: Larson, G.; Fry, J. L. "Ionic and Organometallic-Catalyzed Organosilane Reductions", Wipf, P., Ed.; Wiley, 2007