Conventional glass corrosion

PTFE is handicapped by the impossibility of using the conventional molten-state processing methods and the difficulty and cost of the suitable specific methods. Additional disadvantages are the sensitivity to creep and abrasion significant dimensional variation around the glass transition temperature (about 19°C) the price (justified by the high performances) density difficulties of joining corrosive and toxic fumes in the event of fire. 

All these polymers incorporate high halogen levels that are environmentally harmful. PTFE creep and abrasion sensitivity injection and extrusion are impossible by conventional processes high dimensional variation at glass transition temperature (19°C) high cost high density very difficult to stick corrosive and toxic smoke generated in fires. 

The conductivity cell is modified from a conventional type. It is made of borosilicate glass, which resists the attack of anhydrous chlorine and bromine trifluorides, and is equipped with two smooth platinum electrodes to minimize electrode corrosive effects. These electrodes are approximately 12x25 mm. in size, held 1.5 mm. apart with borosilicate glass spacers. The arrangement of electrodes and leads is shown in Figure 1. An internal thermocouple well leads from the top of the cell to a point near the electrodes and contains a copper constantan thermocouple. The cell constant is determined by measuring the cell resistance... 

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