We performed small-angle neutron and X-ray scattering (SANS and SAXS) measurements on an elongated blend of low molecular weight deuterated polyethylene (PE) and high molecular weight hydrogenated one (97.2/2.8) in a very wide range of scattering vector of 1 × 10-4−3 Å-1 to elucidate hierarchic structure of the so-called shish-kebab. Comparing the SANS and SAXS data, we found that the hydrogenated high molecular weight PE formed a large and long object aligned along the elongation direction. The SANS data were analyzed in terms of the multicore−shell cylinder model, and we found that the long oriented structure had radius of ∼1 μm and length of ∼12 μm and included about three extended chain crystals with radius of ∼45 Å. We believe that this oriented long object with a relatively low aspect ratio of about 12:1, which is called the row structure in this paper, is a precursor formed from deformation of network of high molecular weight components due to entanglements.

SANS‐J (a pinhole small‐angle neutron scattering spectrometer at research reactor JRR3, Tokai, Japan) was reconstructed as a focusing and polarized neutron small‐angle scattering spectrometer (SANS‐J‐II). By employing focusing lenses of a biconcave MgF2 crystal or of a sextupole permanent magnet and a high‐resolution photomultiplier, the minimum accessible magnitude of the scattering vector qmin was improved from 3 × 10−3Å−1 to an ultra‐small‐angle scattering (USAS) of 3 × 10−4 Å−1. Compared with a Bonse–Hart double‐crystal method, the advantages of focusing USAS are the efficient detection of anisotropic USAS with an area detector, an improvement in q resolution Δq/q at conventional magnitudes of the scattering vector q ~ 10−3 Å−1 and a gain in neutron flux in the conventional q region of q ~ 10−3 Å−1.

The small and wide angle neutron scattering instrument (TAIKAN) is designed to cover the wide q range of 0.005 < q < 15 Å-1 by using neutrons in the wide wavelength range of 0.5 < < 7.8 Å and four detector banks of small-, middle-, high-angle, and backward detector banks. The q resolution of TAIKAN was theoretically estimated to be about 5 % at q = 0.1 Å-1 with the small-angle detector bank and less than 2 % in the q range of q > 0.3 Å-1 with the other banks. The q resolution was compared with the values experimentally obtained from the widths of Bragg peaks of a standard sample, silver behenate. The results of the experiment were consistent with the theory. It was confirmed that TAIKAN was completed as was expected.

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