Polyethylene
Description
A thermoplastic polymer or copolymer of ethylene. Ethylene was first polymerized in 1933 by ICI in England and was commercially released as Alkathene in 1939. In 1954, Karl Ziegler developed a process for high molecular weight polyethylene that allowed it to be spun into fibers, molded into durable but flexible forms and cast as tough thin sheets. Polyethylene made by the original process is now called Low density polyethylene (density = 0.92, melting pt=110-120 C) while polymers made by the later Ziegler or Phillips processes are called High density polyethylene (density=0.95-0.96, melting pt=130-138C). Polyethylene is a translucent waxy polymer with good impact strength and tensile strength. It is widely used for packaging, coatings, liners, plastic sheets, wire coatings, underwater cables, containers, waste bags, toys, and squeeze bottles. Small amounts of additives (antioxidants, light stabilizers, slip agents, antistatic agents, flame retardants, pigments, etc.) are typically added to the final products. Polyethylene is recyclable and many products, such as Tyvek, contain the recycled polymer.
Synonyms and Related Terms
PE; polietileno (Esp.); polythylne (Fr.); polietilene (It.); polietileno (Port.); polyolefin; polythene; alkathene
Examples: Volara; Ethafoam; Tyvek [DuPont]; Hi Core [Matra Plast]; Tupperware; Lennite; Corrulite;
Other Properties
Soluble in xylene, trichlorobenzene, decane at room temperature and most chlorinated and aromatic solvents when gently heated. Insoluble in acetone, diethyl ether.
Burns with yellow flame and blue center that smells like paraffin.
Floats on water.
| Composition | [-CH2-]n |
|---|---|
| CAS | 9002-88-4 |
| Melting Point | 110-138 |
| Density | 0.92-0.96 |
| Refractive Index | 1.52 |
Hazards and Safety
Degraded by ultraviolet light and sulfur containing pollutants.
May contain additives (such as antioxidant BHT) that can migrate to adjacent materials and cause staining.
Dow Corning: MSDS
Comparisons
Physical Properties for Selected Thermoplastic Resins
General Characteristics of Polymers
Additional Images
Ethafoam
Sources Checked for Data in Record
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