The two general categories of Polyethylene are Linear and Crosslink. While there are a great many properties that are common to both types, each has its own strengths and weaknesses.

Crosslink Polyethylene was the first type to be produced and found favor versus metal in many applications due to lower cost and chemical resistance. Over many years, Linear Polyethylene was developed. Linear Polyethylene has become the dominant and in most cases, the preferred type for use today in rotational molding.

Linear Polyethylene has undergone much more rapid development over the past several years. It now exists in Low, Medium and High density. The characteristics of the different densities vary widely. Most companies that produce Crosslink tanks make convenient comparisons to the Linear type against which they compare most favorably for a given characteristic. It is important to know what type of Linear Polyethylene is being used to make accurate comparisons.

The main advantages of Crosslink are:

• Some Chemicals (especially fuel) should only be stored in Crosslink.
• Crosslink has better impact strength when used with non-extreme applications.

The main advantages of High Density Linear are:

• Linear polyethylene is FDA approved.
• Pricing on Linear tanks is almost always lower.
• Linear polyethylene can be welded and repaired.
• Linear polyethylene can be easily recycled.
• Some Chemicals should only be stored in Linear.
• Linear Polyethylene has better impact strength and tensile strength under extreme applications like sulfuric acid.

The common traits of Linear and Crosslink are:

• Many chemicals can be stored in either type.
• UV stabilization material is available and almost always included in each type.

It is important to bear in mind that this is general information provided to give you a general understanding of the differences between the type of polyethylene. You should not make decisions involving specific applications without getting detailed assistance from a qualified individual such as a chemical engineer.