Preparation, Characterisation And Properties Of Uscovite/Acrylonitrile Utadiene Styrene Nanocomposites

The development of acrylonitrile butadiene styrene (ABS) nanocomposite based on non-expandable clay minerals presents a promising approach that has been relatively unexplored. Muscovite was chosen over the most commonly used clay minerals, due to its higher aspect ratio when compared to montmorillonite (MMT). As such, this study investigated the possibilities of muscovite to expand and to function as reinforcement filler in ABS matrix via two-stage ion exchange process for fillermatrix compatibilisation and melt compounding for polymer fabrication. The modification process involved treatment with LiNO3 (first-stage) and modification with cetyltrimethylammonium bromide (CTAB) at various concentrations as a secondstage cation exchange reaction. Characterisation of treated muscovite was assessed by using X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transform infrared (FTIR), Brunauer–Emmett–Teller (BET), Field emission scanning electron microscopy (FESEM) coupled with Energy dispersive x-ray spectroscopy (EDX), and Transmission Electron Microscopy (TEM). The experimental outcomes showed that not only basal spacing, but also specific surface area increased while the number of stacked individual silicate layers of organoclay kept decreasing at high CTAB concentrations, which signified separation within the muscovite layers. The changes in basal spacing further evidenced that muscovite displayed a possibility for expansion. A further goal of this research is to extend the application of organomuscovite (OM) filled ABS matrix. In this case, OM and unmodified muscovite were embedded in ABS matrix at various filler loading of 1, 3, and 5 wt.%. The aspects addressed included the effect of ion-exchange process, the degree of dispersion that was achieved, and the effect of various filler loading on the mechanical properties of ABS nanocomposites. Along this line, this study reveals that the ABS/OM nanocomposites possessed a tendency to exemplify enhanced mechanical properties, in comparison to those of ABS/muscovite. Nevertheless, incorporation of muscovite at all filler loadings led to a slight reduction in tensile strength, a significant decrease in elongation at break, a slight improvement in modulus and hardness, and increment in thermal stability over those of the neat ABS. Flexural strength and modulus were improved by 10% and 28%, respectively, when compared to those retrieved from neat ABS. Both wide angle x-ray diffraction (WAXD) and TEM analyses indicated the formation of mixed intercalated and exfoliated structures with incorporation of OM. Therefore, the development of non-expandable muscovite incorporated with polymer matrices provide the opportunities to explore new functionalities beyond those found in conventional materials

Characterization and thermal properties of chitosan/agar blends hydrogel membranes / Faiezah Hashim, Nor Hafizah Che Ismail and Mohd Lias Kamal

Continuous awareness of ecological problem has led to a paradigm shift on the use of biodegradable materials, especially from renewable agriculture feedstock and marine food processing industry wastes. Developments in the field of biomaterials have lead to significant advancements in the extraction of chitosan from local sources. Chitosan has been found in applications for biomedicine (wound dressings), tissue engineering (artificial skin), bone tissue engineering and one of the promising materials for preparing hydrophilic membranes and it has been widely studied. Most of the chitosan membranes so far have been fabricated using commercial chitosan. Nowadays, the main sources of chitosan are crab and shrimp shell. As the combination of properties of chitosan such as water binding capacity, fat binding capacity, bioactivity, biodegrability, and antifungal activity, chitosan and its modified analogs have shown many applications in medicine, cosmetics, agriculture, biochemical separation systems, tissue engineering, biomaterials and drug controlled release systems. However, chitosan also has some drawbacks, it being soluble in aqueous medium only in the presence of small amount of acid. Its mechanical properties have also proved to be unsuitable in some biomedical applications. In order to eliminate the disadvantageous, it can be modified by physical blending or/and chemical modification by grafting, interpenetrating polymer networks and crosslinking method. In this study, an attempt has been made to blend chitosan with other gelling material which is agar. Biopolymer from agar (polysaccharide) has received particular attention due to their natural origin, low cost and good compatibility. Since agar have good compatibility with most other polysaccharides and with proteins in near neutral conditions, blends of agar with chitosan may lead to the enhancement of the physical properties of chitosan membran

Determination of groove and mechanical properties of underside shaped concrete paver

This paper presents an innovative paver with groove beneath the normal rectangular paver, named as the Underside Shaped Concrete Paver (USCP). A known fact, there is less friction between surface at beneath of paver and bedding sand. Therefore, USCP provide their own grip to bedding sand especially during compaction process. The process of groove determination was first performed before the USCP were tested for compression and flexural strength. The groove was determined based on the theory of bending stress. Combined with several factors, the basic groove shapes chosen were rectangular and triangular. Results indicated that some groove shapes are better in compression, but have weak flexural strength and vice versa. In fact, the relationship between mechanical properties and groove shape is indisputable. It is hoped that the outcomes can be considered in the future to design desirable paver

The effect of groove-underside shaped concrete block on pavement permanent deformation

The aim of this study was to investigate the permanent deformation of Concrete Block Pavement (CBP) with the underside surface grooved. Permanent deformation is one of the important factors that influence pavement performance and often happens due to increases in axle load and tire pressure. Such increments have also resulted in greater increment of contact pressure at the tyre-pavement interface. In this study, a new CBP was developed with the concrete blocks grooved at the underside block surface to reduce pavement permanent deformation, termed as Underside Shaped Concrete Blocks (USCB). 13 USCBs were manufactured in the laboratory in this study with their patterns divided into three categories. The CBP models were constructed, from bottom to top, with hard neoprene, 70 mm thick loose bedding sand, and jointing sand which was used to fill in the gaps between USCBs. The test pavement was subjected to 10,000 rounds of load repetition under 1,000 kg single wheel load using the first Malaysian accelerated loading facility called Highway Accelerated Loading Instrument (HALI). The pavement was examined in terms of transverse deformation profile, average rut depth along the wheel path, and longitudinal rut profile other than being visually inspected. Results indicated that permanent deformation is significantly influenced by USCB geometry, groove shape, groove depth, bedding sand settlement during block setting, and load repetitions. From the results, it has been proven that USCB is a potential choice for CBP construction to reduce permanent deformatio

Interaction between bedding sand thickness and shell groove-underside shaped concrete block pavement

Underside Shaped Concrete Block (USCB) has groove shaped at the underside block surface to produce resistance in horizontal plane and to grip onto the bedding sand layer. However, the horizontal movement of block units is the major problem in pavement due to vehicle braking and accelerated action. This paper presents the laboratory evaluation on vertical and horizontal displacement of shell groove-USCB pavement laid onto different bedding sand layer thickness. A pavement laboratory test was conducted to investigate the interaction between USCB type of the Shell-Rectangular 15 mm (Shell-R15) and bedding sand on three different loose bedding sand layer thicknesses of 50 mm, 70 mm and 90 mm respectively. Then, push-in loading test and horizontal loading test were performed. The results showed that interaction between USCB Shell-R15 and bedding sand layer thickness had significant influence to the vertical and horizontal displacement compared to control of 50 mm loose bedding sand layer thickness. The loose bedding sand layer thickness of 70 mm performed better compared to others

Science@IIUM Issue 3

Science@IIUM is a magazine that celebrates the members of Kulliyyah of Science, IIUM. Through interviews, image stories and curated content, Science@IIUM highlights the success and anecdotes from those who explore and challenge themselves in academics and also in other areas