No abstract

The effect of nanocrystalline cellulose (NCC) and nanofiber cellulose (NFC) was estimated as a means of reinforcing and compatibilizing agent of polypropylene/ cyclic natural rubber (PP/CNR) blend in terms of mechanical and thermal properties. The morphological effect of NCC and NFC on the PP/CNR blend property was determined through several characterization techniques, i.e. SEM, contact and TGA/DTG. Scanning electron microscopy (SEM) images revealed that the addition of NCC and NFC became more homogenous than without the addition of nanocellulose. The improvement of nanocomposites was also observed on the result of interphase surface tension and thermal stability. This improvement was assumed as the result of physically/ chemically interaction of nanocellulose with the backbone of PP and CNR, in which the nanocellulose can be imagined acting as a bridge to link the PP and CNR’s backbone.

Cellulose nanofiber (CNF) gel has been obtained from TEMPO-oxidized differently treated lower part of empty fruit bunches (LEFB) of oil palm. Three kinds of materials were initially used: (i) α-cellulose, (ii) raw LEFB fiber two-times bleaching, and (iii) raw LEFB three-times bleaching. The obtained nanofibers (CNF1, CNF2 and CNF3, respectively) were then characterized using several methods, e.g. FT-IR, SEM, UV-Visible, TEM, XRD and TGA. The LEFB at different levels of bleaching showed that the Kappa number decreased with the increase of the bleaching levels. The decrease of lignin and hemicellulose content affected the increase of the yield of fibrillation and optical transmittance of CNF2 and CNF3 gels. The FT-IR analysis confirmed the presence of lignin and hemicellulose in the CNF2 and CNF3 film. Based on TEM analysis, the lignin and hemicellulose content significantly affected the particle structure of CNFs, i.e. CNF1 was found as a bundle of fibril, while the CNF2 and CNF3 were visualized as individual fibers and interwoven nanofibril overlapping each other, respectively. The XRD data of the CNF’s film showed that CNF2 and CNF3 have a lower crystallinity index (CI) than CNF1. The presence of lignin and hemicellulose in the CNFs decreased its decomposition temperature.

The oil palm's nanocrystalline cellulose (NCC) has been successfully isolated and characterized, also it has been applied in the emulsion system of cyclic natural rubber (CNR). Nanocrystalline cellulose (NCC) has been isolated and characterized from the lower part of empty fruit bunches (LEFB) by acid hydrolysis and followed by ultrasonication treatment. The obtained NCC has characteristic, such as (i) the crystallinity index of NCC was 77.84% and the dimension of NCC was 30-450 nm and 20-35 nm of length and width, respectively. The utilization of NCC in the emulsion's system of CNR can improve the stability of the emulsion system that measured by ESI value. The emulsion's system of CNR has divided into two groups based on the type of surfactants, such as Tween 80 and Lutrol F127. In the emulsion that prepared by Tween 80, at 28 th days after the addition of NCC (2-29% of fibril dosages), the ESI value was in the range 70-100% and linear with the fibril dosages.

The doping process of TiO 2 using a combination method, sol-gel and hydrothermal, has been conducted. The presence of anatase and rutile phase of TiO 2 and doped TiO 2 has been confirmed using UV-DRS, XRD, Raman spectroscopy, and EPR. The Nitrogen-doped TiO 2 (N-TiO 2) showed the highest photoactivity in the powder form than the as-prepared TiO 2 (rutile), anatase and Vanadium-doped TiO 2 (V-TiO 2). The influence of pH during the preparation of N-TiO 2 showed that pH gives a big effect to the morphology and photoactivity of the photocatalyst. The N-TiO 2 at pH 2 showed higher photoactivity than N-TiO 2 at pH 4 and it also showed a fine morphology. The N-TiO 2 also showed the highest photoactivity when it was immobilized in the DPNR matrix. After being immobilized, the photoactivity of the asprepared photocatalyst was decreased to be 0-30%.