Yoshitaka Aranishi

Blends and Graft Copolymers of Cellulosics

This chapter is a general introduction to the present monograph and first describes the significance of the studies on “Blends and Graft Copolymers of Cellulosics” in the research field of compositional materials based on cellulose and related polysaccharides. Secondly, some technical key-terms and methods used for characterizing cellulosic blends and graft copolymers are explained. Finally, the outline of this book is provided by summarizing the main subjects of the constituting chapters with a perspective to tie together the subjects.

Cellulosic Fiber Produced by Melt Spinning

This chapter focuses on a “melt-spun” cellulosic fiber that was developed through an industry—university cooperative research project. Fiber-formable cellulose is one of the oldest and most familiar apparel materials for humans. However, conventional cellulosic fibers in filamentous forms, such as viscose rayon and acetate rayon, are produced by a solution spinning process that requires conditionally harmful solvents and other reagents. In the present research, the major aim was to design a thermoplastic cellulose derivative and produce filamentous fibers from it using a solvent-free, melt-spinning process. Improved thermal processability of raw cellulose by chemical modification and polymer blending was crucial for successful melt spinning. In relation to the rheological conditioning of the cellulosic composition, we also discuss industrial technical aspects regarding the control of the elongational flow-viscosity and running speed of the filaments in the practical melt-spinning process. Finally, we demonstrate that the melt-spun cellulosic fiber and ensuing textiles exhibit standard properties and distinct functionalities suitable for apparel use. Examples include the facile design of various types of fibers with different cross sections, which are usually not obtained with solution-spun cellulosic fibers.