Synthesis and characterization of ultra violet curable renewable polymer graphite composites

This thesis aims is to evaluate the synthesis and characterization of ultra violet (UV) curable renewable polymer graphite (RPG) composites. Accordingly, the renewable polymeric composites were prepared through a film slip casting method at room temperature wherein graphite particles of various weight loadings were mixed with mass proportion 2:1 of renewable monomer and Methylene Diphenyl Diisocyanate, MDI respectively. The main concerned was given to renewable monomer based vegetable cooking oil produced at the SPEN-AMMC UTHM. The morphology-structural relation of the RPG composites confirmed that the graphite particles contain functional groups such as hydroxyl and carboxylic groups are randomly distributed and attributed to formation of interconnected interface within the polymeric composites. Furthermore, as the graphite particle loading increased, the thermal degradation temperature at three distinct decomposition stages shifted and to some extent, resulting in much higher crystallinity. As expected, the mechanical properties of the composites were also enhanced with the modulus and tensile strength increment up to ~440% and ~100% respectively. Significantly, all of these results correlate with viscoelastic properties in which the composites achieved percolation threshold at RPG20 composites. Moreover, the decreased in optical energy band gap (Eg) which afterwards took the leads to electrical conductivity (σ). Aptly, the composites (RPG20, RPG25 and RPG30) were found to possess favorable electrical conductivity range of 10-5 – 10-4 S/m, while all other samples were deemed to be not conductive due to improper dispersion of graphite particulates. On the contrary, UV curable composites did not show any significant enhancement and graphite particle acted as UV stabilizer in this manner. Therefore, the stability of the conductive renewable polymer graphite composite is suitable to be used in various composites applications

Characterization and treatment of titanium dioxide, TiO2 via ultrasonic process with melastoma malabathricum as sustainable sensitizer for photovoltaic slar cell

Dye-sensitized solar cells (DSSCs) have been fabricated with doped Titanium Dioxide, TiO2 which are based on natural dyes from Malaysia tropical fruits, wherein contain interlocking groups; the carbonyl and hydroxyl groups of the anthocyanin molecule which enhance the photosensitization effect due to the high interaction on the surface of the film. Such a natural dye extracted from Melastoma Malabathricum can be subjected to molecular tailoring to give a superior dye preparation, offering a wide range of spectral absorption; covering the entire visible region (400 – 700 nm). This study is based on a series of TiO2 preparations designated U1 and U2 (without and with additive respectively), and those treated with ultrasonic energy, namely U3 and U4 (without and with additive respectively). 10 minutes of sonication of the metal oxide led to its breakdown from agglomeration at the micro to the nano scale. Furthermore the additive (4-tert-butylpyridine) in potassium iodide, KI3 electrolyte, effects the rate of electron injection into the oxidized dye sensitizer. Sonication of TiO2 reduced the particle size agglomerates from 0.37 µm down to 0.15 µm; this treatment led to a more consistency with high porosity, enabling enhance absorption and anchorage of the dye sensitizer. Sonicated sample U4, with addition of electrolyte additive gives, open circuit voltage, Voc= 0.742 V, short circuit current, Isc= 0.36 mA, fill factor, FF= 57.012 and 0.039 % of cell’s efficiency. Evidently, sonication and addition of additive for KI3 electrolyte offer enhanced capability for further application

Deterioration rate of renewable polyurethanes composites prior to ultra violet irradiation exposure

Polyurethanes (PU's) made from renewable and sustainable materials are one of the most important groups of polymers because of their versatility with wide range of grades, densities and stiffness. In this project, polymers based on renewable materials such as rapeseed (RS) and sunflower oil (SF) were synthesized and cross-linked to form polyurethanes. The effect of prolonged exposure up to 1000 h upon UVB light, in general promotes photodegradation for both RS and SF-based polyurethanes, both neat and also composites loaded with TiO2. The addition of 10% Degussa P25 TiO2 pigment, gives the greater degradation while PUs loaded with 5% Kronos 2220 show the slowest rates of degradation due to the effect of the coating of this pigment. The photostabiliser Tinuvin 770 offers high protection from UVB, thus lead the combination of Tinuvin 770 with Degussa P25 promotes the highest protection from UVB exposure. Moreover, addition of Tinuvin 770 at the stage of preparation of the PUs also greatly reduced the undesirable yellow colouration prevalent during PU synthesis

Segmented phase of ultraviolet (UV) curable thermoset polyurethanes-graphite (TPU-G) composites

Segmented thermoset polymeric materials properties mainly classified through its carbonyl hydrogen bonding. The addition of graphite particle loading in polymeric materials tailored the functional characteristic of the composites. Therefore, the carbonyl hydrogen bonding in the hard segments of the synthesized segmented ultraviolet (UV) curable thermoset polyurethanes-graphite (TPU-G) composites was identified. This composites based green polymer incorporated with varying graphite particles loading were prepared through slip casting method which cure upon UV light. These result in an enhancement of the carbonyl hydrogen bonding which tribute to degree of phase separation (DPS %) in the TPU-G composites ranged from 10-20%, as compared to that in the pure TPU. In addition, the spectroscopy detects the formation of carbonyl hydrogen groups within the TPU-G composites although they are prone to chain scission and undergo photo oxidation subjected to ultraviolet (UV) curing. Upon UV curing, higher graphite weight loading (TPU-G20, TPU-G25 and TPU-G30 composites), shows higher and stable DPS% value, attribute to soft segment- soft segment and hard segment- hard segment establishment. Therefore, the graphite particles dominantly absorb the incident radiation instead of thermoset polyurethane without changing its based

Enhancement of graphite functionality in renewable polymer composite properties

The preparation and characterization of composite thin films of renewable polymer graphite (PG) is disclosed. Thin films ~ 0.1 mm thick are prepared using a simple solution mixing with mass proportion of 2/1 (renewable monomer/ Methylene Diphenyl Diisocyanate, MDI), upon differ graphite content (PG0 , PG5 , PG10, PG15, PG20, PG25 and PG30) and drop casting at room temperature. The morphology-structure relations of renewable PG composites with respect to electrical conductivity were diagnosed using Optical microscope (OM), Fourier transform infra-red spectroscopy (FTIR) and Thermogravimetric analysis (TGA). The homogeneous random dispersion and strong interface between the graphite in the classical insulating renewable polymer matrix were observed. Thus resulting of enhancements in thermal stability with slight shift of decomposition temperature and better mechanical properties through the modulus and tensile strength increment up to ~440% and ~100% respectively. The result shows that it can simultaneously leads to renewable PG conductivity (σ) where the percolation threshold occurs at higher graphite content (PG20, PG25 and PG30) of 103 - 104 S/m. Thus, this non-petroleum based renewable polymer graphite composites have remarkably more to offer as conducting polymer composites material in multidisciplinary applications

Transformation of Masjid: empowerment of Muslims economy through e-halal one stop centre (E-HOSC)

Economy is one of the important tools in the upbringing of human’s civilization. Looking back at the Golden Age of Islam, Muslims merchants were all over the world not just for trading purposes but also to spread the beautiful teaching of Islam. During the reign of Caliph Harun al-Rashid (170-193 A.H.) the Muslim world experienced the best moment where each members of the society was taking part in the economic activities as they wanted to contribute to the society. Thus, it led to the level of almost no poverty at all (Ismail, 2012). History also portrayed that Prophet Muhammad sallahu’alaihiwasallam and many of the sahabah were successful businessmen. However, it seems the world has gone upside down where most of the Muslims nowadays have been left far behind and live in poverty and abused by others. Therefore, the role of Mosque need to be revised on the basis of Islam as a syumul religion which comprises all life segments including the economy or muamalat. e-Halal One Stop Centre (e-HOSC) is being proposed to help the Muslim entrepreneurs especially to those who are still searching for the best platform to market their products with zero cost and in the same time helping the consumers to find halal products from Muslim producers. This program is the extension of eHalal4All Program (Abdul Rahman Ahmad Dahlan et al, 2014), with the aim to enhance the economic and social well being of rural communities in Sabah, Malaysia. e-HOSC will be maintained and supervised by Masjid Negara (National Mosque) supported by Jabatan Kemajuan Islam Malaysia (JAKIM) and SME Corp as the centre and will be integrated with all mosques in Malaysia via Network-of-Mosques (NoM). Masjid Negara is being proposed as the administrator as one of its functions is to make a range of activities for Muslim community and it is an established organization where it has publication and multimedia unit which can be assigned to manage e-HOSC portal. Literature review and Business Model Canvas will be used as the methodology approach. Also, we would adapt the concept used by online marketplaces like Amazon.com or Mudah.my and leveraging on mobile apps to ensure the acceptance, reliability and efficiency of the program. This program is expected to enhance the Muslim entrepreneurs and increase their market shares and indirectly, people will be closer to the mosque and thus, proved the completeness of Islam as the way of life

Combination effect of tamoxifen and ascorbic acid treatment on breast cancer cells (MCF-7) and cervical cancer cells (HeLa)

Breast cancer and cervical cancer are among the leading causes of death among women in the world. Even though chemotherapy is available as cancer treatment, the development of drug resistance in both cancer cells has reduced the efficacy of chemotherapeutic drugs in such treatment. The current study was aimed to evaluate the cell viability of human breast cancer cells, MCF-7, and cervical cancer cells, HeLa upon the combination treatment of ascorbic acid and tamoxifen. The cell viability was measured using the MTT assay, with an incubation period of 72 hours in a humidified CO2 incubator. The concentrations of tamoxifen and ascorbic acid that reduced 50% of the cell population (IC50) were determined from the dose-response curve. The IC50 concentration was used to determine the cell viability in the treated cells. CompuSyn software was used to evaluate the combined effects towards both cells upon treatment and the results were calculated as combination index (CI). The data were analyzed using GraphPad Prism (version 7). Statistical analysis was performed using an independent t-test. The IC50 values of tamoxifen and ascorbic acid on MCF-7 cells were 14.53 μg/ml and 15.8 μg/ml respectively, while the IC50 values of tamoxifen and ascorbic acid on HeLa cells were 11.09 μg/ml and 202.3 μg/ml respectively. The combination of tamoxifen and ascorbic acid exerted a greater growth reduction percentage in both cells compared to tamoxifen alone. The results indicated that ascorbic acid synergizes the cytotoxic effect of tamoxifen at lower concentrations towards MCF-7 cells with a CI less than 1. However, the combination of tamoxifen and ascorbic acid exerted an antagonistic effect in HeLa cells, with a CI more than 1

Carbon Sequestration of Limestone Mine Waste through Mineral Carbonation and Utilization as Supplementary Cementitious Material

This study highlights the potential of limestone mine waste for mineral carbonation and its potential as supplementary cementitious material. Mineralogical and chemical composition analysis of limestone mine waste sample were performed, and mineral carbonation experiment was conducted under ambient pressure and temperature. The effect of particle size and pH condition was investigated to observe the influence of the parameters on carbonation efficiency. The limestone mine wastes were identified to have potential for carbon sequestration due to its high calcium oxide content alongside magnesium oxide which are derived from Ca- and Mg-carbonate minerals. It can be seen from this study that smaller particle size and pH 10 condition were ideal for the carbonation process. The end product of calcium carbonate proved that mineral carbonation occurred during the reaction, indicating the potential of the mine waste as feedstock for mineral carbonation. Additionally, the use of limestone mine waste can also be regarded as supplementary cementitious material due to its chemical composition while at the same time serves as potential storage and sink for sequestered carbon dioxide

Pengaruh faktor keruangan dan masa dalam menentukan kadar pintasan hujan di kanopi hutan dipterokarpa, Tasik Chini Pahang.

The reduction of rainfall by interception process is influenced by two mechanisms namely climate and plant physiographic features. Climate features that affecting the interception loss including total rainfall (mm), wind speed (m/s) and temperature (°C). Meanwhile plant physiographic features that affect interception loss consists of tree’s height, skin, diameter, canopy, twigs and branches. Looking the role of climate and plant physiographic features in the interception process, this study was conducted in order to measure the throughfall, stem flow and interception loss and the factors that influence it. The assessment of throughfall and interception loss were carried out on study plot sized 100 x 100 meter in Dipterocarp Forest of Tasik Chini, Pahang. The study was conducted from October 2009 until January of 2010. Thirty tree samples are used and each tree is well-identified based on their species, family, diameter breast height (DBH), canopy size and its density. Four sets of throughfall were used to do throughfall measurements. Results of this study found that the value of throughfall and stem flow collected based on four rainfall events namely in October 2009 where 0.66 % (TF) and 99.34 % (SF), November 2009 – 0.54 % (TF) and 99.46 % (SF), December 2009 – 0.72 % (TF) and 99.28 % (SF) and January of 2010 – 0.49 % (TF) and 99.51 % (SF). Statistical analysis also indicates the existence of the relationship between total rainfall and interception loss with significant levels in 0.571 (r2) in December of 2009. This study provides important information that related to the hydrological cycle and how plant’s canopy can be acted as a medium of water balance in the environment

Characterization and Treatment of Titanium Dioxide via Ultrasonic Process with Melastoma malabathricum as Sustainable Sensitizer for Photovoltaic Solar Cell

Generation from the existing commercial devices costs about ten times more than the conventional methods. Therefore, this paper presents a thin-film dyed solar cell (DSC) of natural dyes from Melastoma malabathricum fruits which consist of the carbonyl and hydroxyl groups of anthocyanin molecule that influences the performance of photosensitized effect due to its bound on the surface of filler. Experimental results comparing engineering grade (>99% purity) of metal oxide; U1 and U2 with treated metal oxide; U3 and U4 using ultrasonic process, which is to break the particle agglomeration from 0.37 μm down to 0.15 μm; this treatment led to a more “sponge-like” consistency with high porosity, enabling enhanced absorption and anchorage of the dye sensitizer. The microstructures of metal oxide were observed using Field Emission Scanning Electron Microscope (FESEM) and Atomic Force Microscope (AFM). Along with the highest performance of I-V measurement given by U4 with open circuit, Voc = 0.742 V, short circuit, Isc = 0.36 mA, fill factor, FF = 57.012 gives 0.039% efficiency the examples for the first outdoor application upon sunlight illumination of such DSC were also reported. Therefore, this ultrasonic treatment and novel dye from Melastoma malabathricum fruit are reliable to be used for further application