Elastomeric binders

Butyl rubber (BR) and polyisobutylene (PIB) are widely used in adhesives as primary elastomeric binders and as tackifiers and modifiers. The main difference between these polymers is that butyl is a copolymer of isobutylene with a minor amount of isoprene (which introduces unsaturation due to carbon-carbon double bonds), while polyisobutylene is a homopolymer. 

Obviously, typical composite propellants are highly filled polymers and, especially in the case of the rubber-based systems, are more nearly granular media than merely filled rubbers. Certain specific differences between the double-base binder and the elastomeric binder lead to some differences in behavior, but many of the resulting properties show similarities. The relationships between bulk properties and microstructure in the rubber-based systems are much better understood than those of the double-base propellants and, therefore, the following discussions focus primarily on the former category. 

Both RDX and HMX are stable, crystalline solids somewhat less sensitive to impact than PETN. Both RDX and HMX are substantially desensitized by mixing with TNT to form cyclotols (RDX) and octols (HMX) or by coating with waxes, synthetic polymers and elastomeric binders. 

Kirk Othmer 11 (1953), 777 stated that AN can be used as an oxidizer in rocket propellants in place of K perchlorate V)Warren (1958), p 1 lists a solid rocket propellant consisting of AN 80, elastomeric binder 18 additives 2%. He also discusses on pp 34-5 the use of AN as an oxidizer in rocket propellants W)Dr L.Deffet, Belgium listed in private communication, 10 March 1954,the following AN expls as currently manufd in Belgium Alkalite, Alsilite, Centralite TA, Cooppalite Dynamite III, Flammivore,... 

Detosheet Flexible Sheet Explosives. Detasheet is a high explosive developed and manufd by the DuPont Co. Composed of integral mixrure of PETN and elastomeric binder, Detasheet is flexible over a wide range of temps, easy to cut and handle, yet, retains most of the expl props of PETN alone. In addition, it is safe to use and is completely water-... 

Havelast [Ametek], TM for an elastomeric binder or impregnant for various reinforcing materials such as Siltemp, as fabric or rovings, asbestos, glass, or graphite. 

The content of the fiber component is typically 3-15%. The elastomeric binder comprises about 3-15%. The rest are fillers. Aramids are used in fiber reinforced gaskets instead of asbestos fibers. Binders typically are synthetic rubbers. Typical components of a gasket formulation are shown in Table 13.5. 

For example, disc brake linings are cross-linked step-by-step with phenol resin and elastomeric binder in complex curing processes lasting approx. 20 h at temperatures as high as 250 °C. 

Chem. Desap. Aq. sol n. of nonionic hydrophobe-modified polymer Uses Thickener for water-based paints, esp. with vinyl-actylics and elastomeric binders... 

Gaskets and other seals are required for use in many applications where adjacent surfaces are to be sealed to prevent fluid or gas leakage [81]. Composite gasket materials made by a wet laid process are comprised of a fiber component which is distributed within an elastomeric binder matrix, together with property improving solid fillers [82]. 

Kaneko M, Nakayama M, Wakihara M. Lithium-ion conduction in elastomeric binder in Li-ion batteries. Journal of Solid State Electrochemistry. 2007 ll(8) 1071-6. 

Polyvinylidenedifluoride (PVDF) has been used widely as the binder for graphite-based anodes in hthium-ion batteries. However, silicon-based anodes with a PVDF-based binder exhibit poor cyclability. Therefore, significant efforts have been made during the last 10 years to develop new binders that can improve the performance of silicon-based anodes. Chen et al. [90] first reported that apoly(vinylidene fluoride— tetrafluoroethylene-propylene)-based elastomeric binder system kept the capacity of the amorphous Sio.6Sno.4 alloy at around 800 mAh/g for 40 cycles, while the... 

PVDF binder only showed 490 mAh/g at the thirtieth cycle. Considering the fact that breakage elongation of the new elastomeric binder is much larger than that for PVDF [91, 92], the elastomeric binder could improve the cycling performance of a silicon-based alloy electrode. 

Liu WR, Yang MH, Wu HC, Chiao SM, Wu NL (2005) Enhanced cycle life of Si anode for Li-ion batteries by using modified elastomeric binder. Electrochem Solid-State Lett 8 A100-A103... 

The ability of Neoprene adhesives to crystallize sets them apart from other elastomeric binders. As a result of crystallization, their cohesive film strength is much greater than that of amorphous polymers. Crystallization is a reversible phenomenon, and at temperatures over... 

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