Solvating action

One other long-term condition that takes place with relatively low level DC fields in the presence of moisture is the migration of the metal of the conductor into the plastic. This was discovered to be a common thing in the past with silver conductors and phenolic insulators. The first instance of field failures were discovered in telephone equipment. The problem can occur with other metals with phenolic and also conceivably with other plastics that are moisture sensitive and can have a solvating action on the conductor metals that they contact. Most of these type plastics should be avoided inside hermetically sealed containers with movable contacts. Vapors released from the organic plastic deposit on the contacts to produce an insulation layer leading to contact failure. 

Powder solids generate heat when immersed in liquids due to the solvation action of the solvent molecules, which destroys the solid interface. This exothermic heat can be measured precisely using advanced calorimeters, which are sensitive to just a few Joules per mole of material. If the surface area of this powder has been measured previously using an independent method, such as by BET adsorption, then it is possible to calculate the surface free energy from the heat of immersion. 

This epoxy ester is a good low temperature plasticizer and effective co-stabilizer in flexibla PVC formulations, its low viscosity and low solvation action are particularly beneficial in plastlsol formulations to improve their rheology characteristics, both as manufactured and after extended storage. Lankroflex E06 possesses an advantage over other epoxy plasticizers in that it does not winterize at low temperatures, and therefore is mors easily handled in cold climates. 

Orapex 4.4 also provides vinyl plastisol and organosol formulations with low initial viscosity and extended viscosity stability by virtue of its low solvating action. 

You can choose and balance for a wide variety of characteristics, Including excellent solvating action, low volatility, low-temperature flexibility and permanence. Two Drapex epoxy plasticizers, Drapex 6.8 eutid Drapex 10.4, are sanctioned by the FDA for certain food contact applications. 

The plots of deposition potential versus time for the two different solutions were markedly different (Fig. 15). The PC solution maintained essentially a constant potential after the initial transient while the potential for the DMSO rose continuously. The initial transient potential was also higher in DMSO which was attributable to the stronger solvation action of this solvent. 

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