It is used in the synthesis of chlorinatedhydrocarbon pesticides and ferrocene; in paint, varnish, andresin manufacture; in elastomers used as water pondliners, and as a repellent for animals such as hares,rabbits, and deer, in winter or in summer. It is applied in theform of impregnated strip on deciduous and coniferous trees,or by spraying around ornamental plants and shrubs.
Cyclopentadiene is a crystalline solid or a liquid (above 32°C) with a disagreeable, camphor-like odor. The Odor Threshold is 0.011 (detectable); 0.020 ppm (recognizable).cyclopentadiene, although a stable molecule, has a strong tendency to form the more stable dimer dicyclopentadiene. This dimerisation already takes place at room temperature and its rate rapidly increases with elevated temperatures. This reaction however is reversible too; dicyclopentadiene "cracks" at temperatures above 140°C to form two cyclopentadiene molecules. The physical properties of pure cyclopentadiene and dicyclopentadiene are given below as well as some product specific characteristics and compositions.