Polythene
	Plastic material resulting from the polymerisation of ethylene (C2H4). Polythene is defined by its grade (hot fluidity) and density (weight/volume).

	Low density polythene
	LDPE or PEBDR The oldest and most used of the polyethylenes. It is the basis of shrink packaging films.

	Linear low density polythene
	LLPDE or PEBDL Increasingly used, its mechanical properties are better than those of low density polyethylene. It is non-shrinkable and is one of the components of thin films.

	Metallocene linear low density polythene
	mLLDPE This is a latest generation linear polythene with improved mechanical and optical properties.

	High density polythene
	HDPE or PEHD Recognisable by its cloudy appearance and crackly touch, it is used to make thin films of high stiffness and great strength.

	Tubular extrusion
	Known as "bubble" or "blown extrusion" Process for converting polythenes that consists in melting the material and shaping it in the form of a bubble through a tubular die.

	Cast extrusion
	Process for converting polythene that consists in melting the material and shaping it in the form of film through a flat die.

	Photodegradable
	Photo-fragmentable Film that fragments under the action of sunlight and heat. Polythene is photo-fragmentable by nature. The thinner the film, the quicker it fragments.

	Biodegradable
	Film that deteriorates under the action of micro-organisms. The products resulting from the deterioration are almost exclusively water and carbon dioxide. Polythene is not biodegradable.

	Water soluble
	Film that dissolves in water. Polythene is not water soluble.