POLYETHYLENE FIBER

Chemically polyethylene (PE) is the most simplest polymer as the repeating unit of the polymer is ethylene ( - CH₂ – CH₂ - ). However, because of the tetravalent carbon atom, the structure can be linear structure or a branched structure. Based on the structure, polyethylene can be of different types as mentioned below:

(1)   Ordered linear structure with little branching or (High Density Polyethylene /  HDPE)

(2)   Linear structure with short side chains (Linear Low Density Polyethylene  / LLDPE)

(3)  Branched chain structure (Low Density Polyethylene / LDPE)

Physical Properties of Polyethylene Fiber

		LDPE	LLDPE	HDPE
Density (g/cc)		0.93	0.94	0.95 – 0.96
Breaking Tenacity (gpd)	Dry	1.0 – 3.0	2.0 – 5.0	3.5 – 7.0
	Wet	1.0  – 3.0	2.0 – 5.0	3.5 – 7.0
Breaking elongation (%)	Std	20 – 80	20 – 50	10 – 45
	Wet	20 – 80	20 – 50	10 – 45
Elastic Recovery (%)	At 1%	100	100	100
	At 5%	95	95 – 96	100
	At 10%	88	90 – 95	100
Average Stiffness (g/d)		2 – 12	10 – 30	20 – 50
Moisture Regain		Negligible	Less than 0.01%

Polyethylene Fiber Properties

ð  All the polyethylene fibers have excellent resistance to acids and alkalis at room temperature. Still then, the fiber degraded by hot concentrated nitric acid (HNO₃) and sulphuric acid (H₂SO₄).

ð  These fibers are more resistance to bleaching agents and solvents below 65°C. However the fiber swells in chlorinated hydrocarbons and aromatics at room temperature. If heated, the fibers will be soluble at around 80°C. The fiber dissolves in xylene and tetralin HDPE fibers show higer degree of resistance than LDPE fibers. For the same effect as that of LDPE, either HDPE fiber has to be heated to higher temperature and/or for higher timings.

ð  These fibers are not attacked by moth and mildew.

ð  These fibers have good resistance to sunlight but it loses strength on prolonged exposure.

ð  These fibers cannot be dyed by ordinary process. However, they can be pigmented during manufacture for colouration.

Application of Polyethylene Fibers

ð  Medical implants

ð  Cable and marine ropes

ð  Sail cloth

ð  Composites like pressure vessel boat hulls, sports equipment, impact shields

ð  Fish netting

ð  Concrete reinforcement

ð  Protective clothing

ð  Can be used in radar protective cover because of its low dielectric constant

ð  Can be used as a lining material of a pond which collects evaporation of water and containment from industrial plants

ð  Useful in geotextile applications

Polyethylene Manufacturers

ð  Reliance Industries Ltd.

ð  Fiber Group Inc.

ð  Fibra S/A

ð  Steen & Co. GmbH

ð  Kemex BV