循環型社会に向けた環境共生型高分子複合材料の開発

九州工業大学博士学位論文（要旨）学位記番号：生工博甲第282号 学位授与年月日：平成29年3月24

Green polymer blends compatibilized with biomass derived-agents

The effect of soybean lecithin (SOLE) and acrylated epoxidized soybean oil (AESO) as biomass-based compatibilizer agents was studied for the purpose of enhancing the compatibility of environmentally friendly thermoplastic/elastomeric blend of poly (lactic acid) (PLA) and synthetic rubber (PI). PI was melt mixed 25:75 into PLA with and without compatibilizer agents by a twin-screw extruder. The content of compatibilizer agents was kept at 0.5 and 2%, rrespectively. The compatibility of SOLE and AESO was investigated with thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and tensile test. From the thermal degradation and morphologic analysis, it was observed that SOLE was more effective in improving compatibility of PLA/PI blend in comparison with AESO. The inclusion of 0.5% SOLE into the blend system led to increment in the thermal stability, approximately, 10°C. Furthermore, a reduction of the size of PI islands distributed homogenously in the PLA matrix with the help of SOLE was observed, indicating the enhancement of interfacial adhesion. In other words, partially compatibilization took place resulting in the minimization of the dispersed PI island size

Simple Manufacture of Surface-Modified Nanolignocellulose Fiber via Vapor-Phase-Assisted Surface Polymerization

This work tackles the disadvantages in the production of functionalized nanofibers from biomass and offers a new methodology to nanofiber-reinforced composite manufacturing. A vapor-phase-assisted surface polymerization (VASP) method has been used to develop surface-modified lignocellulosic nanofibers. Through the vaporized monomers during polymerization, the polymer chains can be introduced deep within oil palm mesocarp fibers (OPMFs) due to their unique porous structure. After OPMFs are modified with polymer chains, the simple Mortar grinder mill–ionic liquid (M-IL) method provides fibrillation from the macro- to nanoscale, retaining the grafted polymer chains. This approach for the functionalization of biomass could lead to the large-scale fabrication of surface-modified nanofibers for reinforced materials and promote innovative implementations of the renewable biomass resource

Dynamically controlled fibrillation under combination of ionic liquid with mechanical grinding

Combination of mortar grinder mill (MG) and ionic liquid (IL) treatment was employed in order to fibrillate fibers from oil palm mesocarp fiber (OPMF) in one-step. The structural changes of OPMF before and after the treatment were examined by Thermogravimetric analysis (TGA), Fourier transformed infrared (FT-IR) spectra, Wide-angle X-ray diffraction (WAXD), Dynamic light scattering (DLS) and Scanning electron microscopy (SEM). Compared with the only use of 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM[BF4]), combination of MG and IL helped to remove hemicellulose and lignin components partially from OPMF, and also fibrillated OPMF fibers at average particle diameter of 127 nm. Afterwards, the fibrillated fibers were utilized as reinforcement material for the purpose of enhancement of mechanical properties of poly(ɛ-caprolactone)(PCL). The addition of OPMF treated with the combined method led to a 64% increase in tensile strength in comparison with that of untreated OPMF. These results indicate that the combined method enables effective fibrillation

Development of Organo-Dispersible Graphene Oxide via Pseudo-Surface Modification for Thermally Conductive Green Polymer Composites

Graphene has attracted lots of researchers attention because of its remarkable conductivity in both electrically and thermally. However, it has poor dispersibility in organic solvents which limited its applications. Polymers with aromatic end group which act as an intercalator were prepared by ring-opening polymerization with ε-caprolactone by utilizing 1-naphthalene methanol (1-NM) as an initiator. These intercalators will exist between graphene oxide (GO) sheets to prevent aggregation via interactions. The attachment of 1-NM on polymer chains was supported by ultraviolet–visible spectra, size exclusion chromatography profiles, and 1H nuclear magnetic resonance spectra. Exfoliated structured functionalized GO (fGO)/polycaprolactone (PCL) (synthesized fGO) nanocomposites that dispersed well in acetone, chloroform, N,N-dimethylformamide, dimethyl sulfoxide, tetrahydrofuran, and toluene were successfully synthesized. This agreed well with the enlarged interlayer spacing in the optimized fGO as compared to that of GO from density functional theory simulations using the DMol3 module that implemented in the Materials Studio 6.0. Furthermore, its potential to be applied as green electronics in electronics, aerospace, and automotive industries was presented, by trailering the thermal conductivity enhancement from the incorporation of fGO/PCL with commercialized biodegradable polymers, PCL, and poly[(R)-3-hydroxybutyric acid]

Development of Environmental-Benign Polymer Compositestowards the Sustainable Society

九州工業大学博士学位論文（要旨）学位記番号：生工博甲第282号 学位授与年月日：平成29年3月24

Simple Manufacture of Surface-Modified Nanolignocellulose Fiber via Vapor-Phase-Assisted Surface Polymerization

This work tackles the disadvantages in the production of functionalized nanofibers from biomass and offers a new methodology to nanofiber-reinforced composite manufacturing. A vapor-phase-assisted surface polymerization (VASP) method has been used to develop surface-modified lignocellulosic nanofibers. Through the vaporized monomers during polymerization, the polymer chains can be introduced deep within oil palm mesocarp fibers (OPMFs) due to their unique porous structure. After OPMFs are modified with polymer chains, the simple Mortar grinder mill–ionic liquid (M-IL) method provides fibrillation from the macro- to nanoscale, retaining the grafted polymer chains. This approach for the functionalization of biomass could lead to the large-scale fabrication of surface-modified nanofibers for reinforced materials and promote innovative implementations of the renewable biomass resource