title: Multiple-perturbation two-dimensional near-infrared correlation study of time-dependent water absorption behavior of cellulose affected by pressure.
abstract: Transient water absorption by cellulosic samples manufactured under varying pressure was monitored by near-infrared spectroscopy to explore the absorption behavior affected by the pressure. A substantial level of variation of the spectral features was induced by the water absorption and changes in the pressure. The detail of the spectral changes was analyzed with a multiple-perturbation, two-dimensional (2D) correlation method to determine the underlying mechanism. The 2D correlation spectra indicated that the compression of the cellulose increased the packing density of the samples, preventing the penetration of water. In addition, the compression substantially disintegrated its crystalline structure and eventually resulted in the development of inter- and intrachain hydrogen-bonded structures arising from an interaction between the water and cellulose. Consequently, the cellulose samples essentially underwent an evolutionary change in the polymer structure as well as in the packing density during the compression. This structural change, in turn, led to the seemingly complicated absorption trends, depending on the pressure.
authors.affiliation: Research Institute of Instrumentation Frontier, Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, Japan. h-shinzawa@aist.go.jp
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Shinzawa
authors.forename: Kimie
authors.initials: K
authors.lastname: Awa
authors.forename: Isao
authors.initials: I
authors.lastname: Noda
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Ozaki
mesh_terms: D000042:Absorption; D002482:Cellulose / Q000737:chemistry*; D011312:Pressure; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D014867:Water / Q000737:chemistry*
chemical_list: D014867:Water; D002482:Cellulose