Siliconas

<p>Siloxane-Based Silane Reducing Agent<br>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.<br>Pendant Functional Fluid; polyMethylHydrosiloxanes, TMS Terminated<br>MethylHydrosiloxane homopolymers are used as water-proofing agents, reducing agents and as components in some foamed silicone systems.<br>Poly(methylhydrosiloxane); Methyl hydrogen siloxane; Polysiloxanes, methyl hydrogen; Siloxanes and silicones, methyl hydrogen<br>Viscosity: 20-35 cStMolecular Weight: 1,800-2,100 g/molMol% Hydride: 100Reduces lactones to lactolsReduces aldehydes, ketones, esters, lactones, triglycerides and epoxides to alcohols with zinc hydride catalysisWith titanium tetraisopropoxide catalysis carries out reductive amination of ketones and aldehydes and the reduction of acids or esters to 1° alcoholsWith TBAF catalysis selectively reduces aldehydes over ketonesUsed to generate tri-n-butyltin hydride ‘in-situ’ and in a one-pot hydrostannylation/Stille coupling sequenceReduces esters to alcoholsExtensive review of silicon based reducing agents: Larson, G.; Fry, J. L. "Ionic and Organometallic-Catalyzed Organosilane Reductions", Wipf, P., Ed.; Wiley, 2007<br></p>

<p>Siloxane-Based Silane Reducing Agent<br>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.<br>Pendant Functional Fluid; MethylHydrosiloxane-Dimethylsiloxane Copolymer, TMS Terminated<br>MethylHydrosiloxane copolymers are the primary cross linkers for 2-part vinyl-addition silicones and intermediates for functional copolymers.<br>Hydrogen dimethicone; Dimethylhydropolysiloxane; Dimethicone/methicone copolymer; Polysiloxanes dimethyl methyl hydrogen, Hydride functional polydimethylsiloxane; Siloxanes and silicones, dimethyl, methyl hydrogen<br>Viscosity: 6,000-9,000 cStMolecular Weight: 50,000-60,000 g/molMol% Hydride: 4-8Potential reducing agents in the mode of HMS-991 or HMS-995Extensive review of silicon based reducing agents: Larson, G.; Fry, J. L. "Ionic and Organometallic-Catalyzed Organosilane Reductions", Wipf, P., Ed.; Wiley, 2007<br></p>

<p>VDT-163: Vinylmethylsiloxane-Dimethylsiloxane Copolymer, TMS Terminated (Pendant Functional Fluid)<br>Vinyl containing copolymers are used as crosslinkers in Pt and peroxide 2-part addition cure elastomers.<br>VDT-163 Properties<br>Viscosity: 2,000,000-4,000,000 cStMolecular Weight: 425,000 g/molVinyl (eq/kg): 0.04-0.08<br></p>

<p>Thermal Silicone Fluid<br>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<br>mating surfaces.<br>1,1,5,5-Tetraphenyl-1,3,3,5-tetramethyltrisiloxane<br>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<br></p>

<p>PDV-1631: Vinyl Terminated Diphenylsiloxane-Dimethylsiloxane Copolymer (Telechelic Functional Fluid)<br>These fluids are most often employed in 2-part addition cure silicone elastomers where special thermal or optical properties are required.<br>PDV-1631 Properties<br>Viscosity: 1,000 cStMolecular Weight: 19,000 g/molVinyl (eq/kg): 0.09-0.12Refractive Index: 1.465<br></p>

<p>DMS-S31: Silanol Terminated PDMS, 1,000 cSt (Telechelic Functional Fluid)<br>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.<br>DMS-S31 Properties<br>Viscosity: 1,000 cStMolecular Weight: 26,000 g/molWt.% OH: 0.1OH (eq/kg): 0.055-0.060<br></p>

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

<p>DMS-S14: Silanol Terminated PDMS, 35-45 cSt (Telechelic Functional Fluid)<br>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.<br>DMS-S14 Properties<br>Viscosity: 35-45 cStMolecular Weight: 700-1,500 g/molWt.% OH: 30.-4.0OH (eq/kg): 1.7-2.3<br></p>

<p>Siloxane-Based Silane Reducing Agent<br>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.<br>Pendant Functional Fluid; MethylHydrosiloxane-Dimethylsiloxane Copolymer, TMS Terminated<br>MethylHydrosiloxane copolymers are the primary cross linkers for 2-part vinyl-addition silicones and intermediates for functional copolymers.<br>Hydrogen dimethicone; Dimethylhydropolysiloxane; Dimethicone/methicone copolymer; Polysiloxanes dimethyl methyl hydrogen, Hydride functional polydimethylsiloxane; Siloxanes and silicones, dimethyl, methyl hydrogen<br>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<br></p>