Dibasic Lead Phthalate (DBLP)
Dibasic Lead Phthalate, 2PbO-PbC6H4(COO)2 1/2H20, is an excellent heat stabilizer, particularly at high temperatures, besides being also effective as a light stabilizer.
It confers excellent long-term protection on Phthalate plasticized PVC compound which is to be subjected to aging at elevated temperatures, due to its low reactivity with plasticizers, particularly the polyester type. This is of particular advantage in cable sheathing. Waldies product is treated with a special organic coating to ensure ready dispersion in PVC.
It has no tendency of migration or separation. It usually stands alone as the only significant volume stabilizer in use for the long-term stability and retention of elongation in some classes of mixes.
Dibasic Lead Phthalate is suitable for all types of pigmented PVC compound, particularly those requiring a long period of heat stability, or which are to be processed at high temperatures or high speed. PVC Compound stabilized by DBLP shows maximum retention of its physical properties when heat aged for prolonged periods.
Preparation of Foamed PVC
Dibasic Lead Phthalate finds its application in the preparation of Foamed PVC and as a stabilizer for the manufacture of gramophone records. Although stabilizers based on Cadmium or Zinc also are effective in this connection, the attainment of a fine, uniform cellular configuration is usually more easily regulated over a wider temperature range with DBLP.
Lead Cable Sheathing
A lead sheath can be used as a chemical barrier in low, medium and instrumentation cables for all kinds of petrochemical projects. The advantages of lead sheathed cables are:
- Protection against the entry of hydrocarbons.
- Protection against moisture ingress.
- Can be used as an earthing or grounding system
- Excellent corrosion resistance.
Lead sheath (Lead or its alloy-variants and sometimes Aluminium) helps prevent the primary moisture ingress and is also rugged in underground applications. Extruded Lead sheath also serves as Metallic Screen. Copper Tape/Copper sheath can also be used but Copper is costly and would rather be used as overhead conductors with less mechanical stresses.