Silicones

<p>DMS-V35: Vinyl Terminated PDMS, 5,000 cSt (Telechelic Functional Fluid)<br>Vinyl terminated polymers are most often employed in 2-part addition cure silicone elastomers.<br>DMS-V35 Properties<br>Viscosity: 5,000 cStMolecular Weight: 49,500 g/molWt.% Vinyl: 0.10-0.13Vinyl (eq/kg): 0.04-0.05<br></p>

<p>DMS-S51: Silanol Terminated PDMS, 90,000-150,000 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-S51 Properties<br>Viscosity: 90,000-150,000 cStMolecular Weight: 139,000 g/molWt.% OH: 0.02OH (eq/kg): 0.010-0.015<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: 25-35 cStMolecular Weight: 1,900-2,000 g/molMol% Hydride: 25-35Reduced volatility grade available, HMS-301Potential reducing agents in the mode of HMS-991 or HMS-999Extensive 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>DMS-S45: Silanol Terminated PDMS, 50,000 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-S45 Properties<br>Viscosity: 50,000 cStMolecular Weight: 110,000 g/molWt.% OH: 0.03OH (eq/kg): 0.015-0.017<br></p>

<p>Pendant Functional Fluid; Methyl Hydrosiloxane-Dimethylsiloxane Copolymer<br>MethylHydrosiloxane copolymers are the primary cross linkers for 2-part vinyl-addition silicones and intermediates for functional copolymers.<br>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>Hydrogen dimethicone; Dimethylhydropolysiloxane; Dimethicone/methicone copolymer; Polysiloxanes dimethyl methyl hydrogen; Hydride functional polydimethylsiloxane; Siloxanes and silicones, dimethyl, methyl hydrogen<br>Viscosity: 5,000-8,000 cStMolecular Weight: 45,000-60,000 g/molMol% Hydride: 0.5-1.5High molecular weight silane reducing agentReduced volatility grade available, HMS-013RExtensive 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>DMS-V42: Vinyl Terminated PDMS, 20,000 cSt (Telechelic Functional Fluid)<br>Vinyl terminated polymers are most often employed in 2-part addition cure silicone elastomers.<br>DMS-V42 Properties<br>Viscosity: 20,000 cStMolecular Weight: 72,000 g/molWt.% Vinyl:0.07-0.09Vinyl (eq/kg): 0.025-0.030<br></p>

<p>DMS-R05: Methacryloxypropyl Terminated PDMS, 4-6 cSt (Telechelic Functional Fluid)<br>Methacrylate and Acrylate functional siloxanes undergo the same reactions generally associated with methacrylates and acrylates, the most conspicuous being radical induced polymerization. Unlike vinylsiloxanes which are sluggish compared to their organic counterparts, methacrylate and acrylate siloxanes have similar reactivity to their organic counterparts. The principal applications of methacrylate functional siloxanes are as modifiers to organic systems. Upon radical induced polymerization, methacryloxypropyl terminated siloxanes by themselves only increase in viscosity. Copolymers with greater than 5 mole % methacrylate substitution crosslink to give non-flowable resins. Acrylate functional siloxanes cure greater than ten times as fast methacrylate functional siloxanes on exposure to UV in the presence of a photoinitiator such as ethylbenzoin. <br>Oxygen is an inhibitor for methacrylate polymerization in general. The high oxygen permeability of siloxanes usually makes it necessary to blanket these materials with nitrogen or argon in order to obtain reasonable cures.<br>DMS-R05 Properties<br>Viscosity: 4-6 cStMolecular Weight: 380-550 g/molRefractive Index: 1.448<br></p>