Effect of partial delignification of kenaf bast fibers for radiation graft copolymerization

Mohamed, N. H.*; Tamada, Masao; Ueki, Yuji; Seko, Noriaki

Journal of Applied Polymer Science, 127(4), p.2891 - 2895, 2013/02

https://doi.org/10.1002/app.37512

Changes in residual lignin of kenaf bast fiber with acidic chlorite using various parameters were conducted to produce partial delignified fiber for radiation graft copolymerization. The effect of delignification temperature, operating time as well as chlorite doses on the residual lignin of the fibers has been reported. Results obtained indicated that the optimal delignification was achieved at 80C for 6h with 0.5% chlorite. The reduction in density, size and tensile strength were attributed to the increase of removal of lignin from the fiber. Radiation induced emulsion graft copolymerization of 4-chloromethyl styrene (CMS) on partial delignified kenaf with residual lignin 2% resulted in higher degree of grafting of about 143% as compared to the undelignified fiber, which showed the absence of grafting degree.

Positron lifetimes and mechanical properties of -irradiated ultra high molecular weight polyethylene

Kobayashi, Yoshinori*; Yamawaki, Masato*; Oka, Toshitaka; Saiki, Seiichi; Mohamed, H.*; Hattori, Kanehisa*; Watanabe, Yoshihiro*

Materials Science Forum, 733, p.147 - 150, 2013/00

https://doi.org/10.4028/www.scientific.net/MSF.733.147

Positron annihilation lifetime spectroscopy (PALS) has widely been used for probing open volume defects in various materials. PALS is in principle non-destructive, yet conventional PALS is not strictly non-destructive because cutting out of two specimens from the material is required. Recently we developed a novel method of PALS, which is potentially applicable to non-destructive, onsite material inspection. In order to explore the possibility of onsite monitoring of polymer degradation by this novel method of PALS, we studied variations of positron lifetime and mechanical properties of ultra high molecular weight polyethylene (UHMWPE) subjected to -irradiation. Correlations were found between the mechanical properties and o-Ps lifetimes, suggesting the feasibility of non-destructive, onsite monitoring of polymer degradation by PALS. The effect of -irradiation on positronium formation is discussed.

Rapid biodiesel fuel production using novel fibrous catalyst synthesized by radiation-induced graft polymerization

Ueki, Yuji; Mohamed, N. H.*; Seko, Noriaki; Tamada, Masao

International Journal of Organic Chemistry, 1(2), p.20 - 25, 2011/06

https://doi.org/10.4236/ijoc.2011.12004

Fibrous catalyst for biodiesel fuel production synthesized by radiation-induced graft polymerization

Ueki, Yuji; Saiki, Seiichi; Seko, Noriaki; Tamada, Masao; Mohamed, N. H.*

no journal, , 

no abstracts in English