Container closure systems definitions

Definition Elastomer vulcanized by sulfur systems vulcanizate offers low gas permeability, good weather/ozone resist., better chem./heat resist, than butyl rubber contains 1-2% chlorine Uses Rubber for tire inner tubes/liners, tire sidewalls, pharmaceutical stoppers, conveyor belts/hoses, anti vibration mounts, food/drug seals, adhesives in closure-sealing gaskets for food containers... 

With [D ] [P ] there is little difference in magnitude between vt and ft hut, as described below, the introduction of ft eliminates the moment closure problem created by the LCB mechanism. These moment definitions collapse the infinite set of equations for polymeric species into a manageable subset, and many of the moments have precise physical meanings. The zeroth live moment, [/cq], is the concentration of polymer radicals in the system (denoted by [Ptot] in Section 3.2.1), and the first live moment, [/ri],is the concentration of monomer units contained in all growing radicals. Similarly, [fo] is the concentration of all polymer chains in the system, and [f i ] is the concentration of monomer units bound in all polymer chains. These values are used to calculate MW averages, where Wn, is the molecular weight of the monomeric repeat unit ... 

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