title: Unprecedented Development of Ultrahigh Expansion Injection-Molded Polypropylene Foams by Introducing Hydrophobic-Modified Cellulose Nanofibers.
abstract: Herein, an ultrahigh 18-fold expansion of isotactic polypropylene (iPP)/cellulose nanofiber (CNF) nanocomposite foams was achieved for the first time using a core-back foam injection molding technique. It was found that CNFs were well dispersed and aligned along the cell wall in the core-back direction. Interestingly, the formations of a hybrid shish-kebab of CNFs and classic shish-kebab of PP were simultaneously achieved in the PP/CNF composites. Finally, we proposed that the combination of local strong melt strength, probably resulting from the strong alignment of CNFs and subsequent formation of hybrid shish-kebab structures, and weak melt strength in the unreinforced PP melt might be the driving force for remarkably enhancing the PP foamability.
authors.affiliation: Department of Chemical Engineering, Kyoto University , Kyoto 615-8510, Japan.
authors.forename: Long
authors.identifier: http://orcid.org/0000-0002-4519-2400
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Chemical Engineering, Kyoto University , Kyoto 615-8510, Japan.
authors.forename: Shota
authors.initials: S
authors.lastname: Ishihara
authors.affiliation: Department of Chemical Engineering, Kyoto University , Kyoto 615-8510, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Hikima
authors.affiliation: Department of Chemical Engineering, Kyoto University , Kyoto 615-8510, Japan.
authors.forename: Masahiro
authors.identifier: http://orcid.org/0000-0003-0870-5438
authors.initials: M
authors.lastname: Ohshima
authors.affiliation: New Business Development Division, SEIKO PMC Corp. , Chiba 267-0056, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Sekiguchi
authors.affiliation: New Business Development Division, SEIKO PMC Corp. , Chiba 267-0056, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Sato
authors.affiliation: Research Institute for Sustainable Humano-sphere, Kyoto University , Kyoto 611-0011, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yano
keywords: cellulose nanofibers; foam injection molding; foamability; melt strength; shish-kebab