For many purposes such as stiffness and stability, polyolefins are crosslinked. However, polyolefins are generally nonreactive and difficult to crosslink. Crosslinking often leads to non-uniform reaction resulting in variable and unpredictable properties. Sun produced a polyolefin material with uniform crosslinking by annealing or heating in steps to at least 30 degrees above the melting temperature during or after crosslinking. The material is then cooled to room temperature under an inert gas, and any oxidized surface material removed. The material may be irradiated before heating and the gases removed from the oven using a purge gas. The result is uniform crosslinking not possible by conventional means.
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|Title Annotation:||INDUSTRY PATENTS; Dehchuan Sun|
|Article Type:||Brief article|
|Date:||Apr 1, 2013|
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