Liquid natural rubber (LNR) is a depolymerized natural rubber (NR) which consists of shorter polymeric chains and lower molecular weight (Mw<105). Hydrogenated LNR (HLNR) was synthesized via the thermal decomposition ofp-toluenesulfonyl hydrazide (TSH) or 2,4,6-trimethylbenzenesulfonyl hydrazide (MSH). The LNR and HLNR structures were characterized by Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies. The percentage of hydrogenation was calculated from NMR spectrum. The optimum percentage of hydrogenation (>90%) was achieved by manipulating the reaction parameters such as sources of diimide, TSH concentration, solvent, and reaction time. The optimum condition was 3 : 1 weight ratio of TSH/LNR ino-xylene at 130°C in 4-hour reaction period.

Liquid natural rubber (LNR) was functionalized into liquid epoxidized natural rubber (LENR) and hydroxylated LNR (LNR-OH) via oxidation using a Na 2 WO 4 /CH 3 COOH/H 2 O 2 catalytic system. Microstructures of LNR and functionalized LNRs were characterized using Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopies. The effect of CH 3 COOH, H 2 O 2 , Na 2 WO 4 , reaction time and temperature. reaction time and temperature on epoxy content were investigated. LNR-OH was obtained when oxidation reaction was conducted at a longer reaction time, higher temperature or excess amount of catalyst. Thermogravimetric analysis (TGA) reported the thermal behavior of functionalized LNRs. Molecular weight and polydispersity index (PDI) were determined using gel permeation chromatography (GPC).

This article reports an efficient, mild-temperature method for the hydrogenation of liquid natural rubber (LNR). The hydrogenation of LNR was studied using diimide generated in situ from the thermolysis of 2,4,6-trimethylbenzenesulfonyl hydrazide (MSH) in o-xylene at 100 C. The effects of reaction temperature, reaction time, solvent, and MSH/LNR weight ratio on the percentage of hydrogenation were evaluated. 1 H NMR analysis revealed that~80% hydrogenation was achieved with a weight ratio of MSH: LNR = 1:1 at 100 C in o-xylene within 60 min.

Silica was extracted from power plant bottom ash by alkali fusion method and used to synthesize MCM-41 and SBA-15. As comparison, MCM-41 and SBA-15 were synthesized by using tetraethylorthosilicate (TEOS) as pure silica source. All synthesized MCM-41 and SBA-15 were characterized using X-ray Diffraction (XRD) and nitrogen adsorption to determine the formation of hexagonal pores, Field Emission Scanning Electron Micrograph (FESEM) was used to observe their morphology while Fourier Transform Infrared Spectroscopy (FTIR) was used to obtain the functional group and removal of surfactant after calcinations. XRD results confirmed bottom ash MCM-41 (BA MCM-41), pure SBA-15 (PSBA-15) and bottom ash SBA-15 (BA SBA-15) have well-ordered mesostructures. N 2 adsorption of pure MCM-41 (PMCM-41), PSBA-15 and BA SBA-15 indicated type IV isotherm while BA MCM-41 exhibit type III isotherm. According to FESEM analyses, the particle morphology of bottom ash mesoporous silica was different from those prepared using pure chemical. Morphology of PMCM-41 and PSBA-15 showed rod like particle while BA MCM-41 and BA SBA-15 exhibited agglomerated particle. PMCM-41, PSBA-15 and BA SBA-15 shows ordered hexagonal, high surface area and narrow pore distribution. Keywords: mesoporous silica, MCM-41, SBA-15Abstrak Silika telah diekstrak daripada abu bawah loji janakuasa melalui kaedah gabungan alkali dan digunakan untuk sintesis MCM-41 dan SBA-15. Sebagai perbandingan, MCM-41 dan SBA-15 telah disintesis dengan menggunakan tetraetilortosilika (TEOS) sebagai sumber silika tulen. Semua MCM-41 dan SBA-15 yang telah disintesis dicirikan menggunakan kaedah pembelauan Sinar X (XRD) dan penjerapan nitrogen untuk menentukan pembentukan liang heksagon, mikroskopi elektron pengimbasan pancaran medan (FESEM) digunakan untuk memerhati morfologi manakala Spektroskopi Inframerah Tranformasi Fourier (FTIR) digunakan untuk mengenalpasti kumpulan berfungsi dan penyingkiran surfaktan selepas pengkalsinan. Keputusan XRD membuktikan debu MCM-41 (BA MCM-41), SBA-15 tulen (PSBA-15) dan debu SBA-15 (BA SBA-15) mempunyai mesostruktur yang teratur. Penjerapan N 2 oleh MCM-41 (PMCM-41), PSBA-15 dan BA SBA-15 menunjukkan isoterma jenis IV manakala isoterma jenis III bagi BA MCM-41. Berdasarkan analisis FESEM, morfologi zarah silika mesoporos daripada debu bawah loji janakuasa adalah berlainan berbanding yang disediakan menggunakan bahan kimia tulen. Morfologi PMCM-41 dan PSBA-15 menunjukkan zarah jenis rod manakala BA MCM-41 dan BA SBA-15 wujud sebagai zarah bercampur. PMCM-41, PSBA-15 dan BA SBA-15 mempunyai struktur heksagon yang seragam, luas permukaan yang tinggi dan taburan liang yang kecil. Kata kunci: silika mesoporos, MCM-41, SBA-15 ISSN -2506Nurul Barakah et al: SYNTHESIS AND CHARACTERIZATION OF MESOPOROUS SILICA MCM-41 AND SBA-15 FROM POWER PLANT BOTTOM ASH 540 Introduction In year 1990s, the researchers of Mobil Corporation discovered MCM-41 molecular sieves can be synthesized by using an inorganic silicate species and organic template [1]. Tetraethylor...