Branch Content of Metallocene Polyethylene
نویسندگان
چکیده
Small-angle neutron scattering (SANS) is employed to investigate the structure and longchain branch (LCB) content of metallocene-catalyzed polyethylene (PE). A novel scaling approach is applied to SANS data to determine themole fraction branch content (φbr) of LCBs in PE. The approach also provides the average number of branch sites per chain (nbr) and the average number of branch sites per minimum path (nbr,p). These results yield the average branch length (zbr) and number of inner segments ni, giving further insight into the chain architecture. The approach elucidates the relationship between the structure and rheological properties of branched polymers. This SANS method is the sole analytic measure of branch-onbranch structure and average branch length for topologically complex macromolecules.
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