Question
What is LDP? How is it prepared? Give its properties and uses.
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Answer
LDP means low-density polyethene. LDP is obtained by polymerization of ethylene under high pressure $(1000-2000 atm )$ and temperature $(350-570 K )$ in presence of traces of $O _2$ or peroxide as initiator.
The mechanism of this reaction involves free radical addition and H-atom abstraction. The latter results in branching. As a result the chains are loosely held and the polymer has low density.
Properties of LDP :
The mechanism of this reaction involves free radical addition and H-atom abstraction. The latter results in branching. As a result the chains are loosely held and the polymer has low density.
Properties of LDP :
- LDP films are extremely flexible, but tough chemically inert and moisture resistant.
- It is poor conductor of electricity with melting point $110^{\circ} C$.
- LDP is mainly used in preparation of pipes for agriculture, irrigation, domestic water line connections as well as insulation to electric cables.
- It is also used in submarine cable insulation.
- It is used in producing extruded films, sheets, mainly for packaging and household uses like in preparation of squeeze bottles, attractive containers, etc.
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