Standards Development

Scope

This document specifies the method for determining the content and chemical composition of soluble fractions of polyolefin of various temperature ranges from room temperature to the complete dissolution temperature in 1,2-dichlorobenzene/1,2,4-trichlorobenzene.

This document specifies a method for determining the chemical composition distribution of semicrystalline polyolefins by crystallization on an inert column from dilute solution in 1,2-dichlorobenzene or 1,2,4-trichlorobenzene and with a subsequent sample elution process.

This document applies to polyethylene, polypropylene and -olefin copolymers of the same.

Purpose

Polyolefin is one of the important general plastics, and the global polyolefin production capacity exceeds 238 million tons/year with approximately 800 product grades for different applications now, like film, fiber, packaging, pipe, automobiles and the others, though there are only three basic types of polyolefins, polyethylene, polypropylene and ethylene-propylene copolymers. The regulation of polydispersity in polyolefin composition endows polyolefin products with diverse properties, allowing polyolefin to be more widely and better applied in many fields. Testing the polydispersity of polyolefin molecular chain structure is one of the directions in the development of testing standards. We already have a method standard for polymer molecular weight distribution using SEC as ISO 16014.Here, we hope to develop the method standard to determine polyolefin fractions with different crystallization abilities for chemical composition distribution by temperature rising elution fractionation method This proposal would be a supplement and improvement for polyolefin quality control in polyolefin process. (Please use this field or attach an annex)