01868nas a2200229   4500008004100000245011600041210006900157260000800226300001200234490000700246520108600253100001901339700002301358700001801381700001801399700001901417700001801436700001601454700002001470700002001490856012801510       2025                        eng d00aSANS and SAXS investigation of the melt state structure in disentangled ultrahigh molecular weight polyethylene0 aSANS and SAXS investigation of the melt state structure in disen  cMAR  a349-3530 v143 a<p>
	Disentangled ultrahigh molecular weight polyethylene exhibits a time-dependent increase in rheology modulus when molten. This originates from its kinetically evolving heterogeneous microstructure consisting of disentangled and entangled regions. We report a quantitative analysis of this microstructure using X-rays and neutrons that capture the signatures of these regions. We analyze the absolute intensities to obtain the volume fraction and size distribution of the disentangled domains in the melt. Employing neutrons, we follow the changes in these parameters with time. The trends are qualitatively similar to those of the previous rheological observations. Our methodology also provides an experimental verification of the theoretical report by McLeish, T. C. B. Soft Matter 2007, 3 (1), 83-87, which predicts the presence of high density disentangled domains in a low density entangled matrix. The analysis presented here is a useful instrument for unveiling the origin of differences in the properties of polymers obtained through different processing routes.</p>
1 aSharma, Aakash1 aKruteva, Margarita1 aWillner, Lutz1 aRomano, Dario1 aPorcar, Lionel1 aDulle, Martin1 aZhou, Fuhai1 aRastogi, Sanjay1 aRichter, Dieter  uhttps://library.ncl.res.in/content/sans-and-saxs-investigation-melt-state-structure-disentangled-ultrahigh-molecular-weight