Suriati Ghazali

Bio: Suriati Ghazali is an academic researcher from Universiti Malaysia Pahang. The author has contributed to research in topics: Superabsorbent polymer & Composite number. The author has an hindex of 10, co-authored 40 publications receiving 823 citations. Previous affiliations of Suriati Ghazali include Universiti Sains Malaysia.

Polyurethane types, synthesis and applications – a review

Abstract: Polyurethanes (PUs) are a class of versatile materials with great potential for use in different applications, especially based on their structure–property relationships. Their specific mechanical, physical, biological, and chemical properties are attracting significant research attention to tailoring PUs for use in different applications. Enhancement of the properties and performance of PU-based materials may be achieved through changes to the production process or the raw materials used in their fabrication or via the use of advanced characterization techniques. Clearly, modification of the raw materials and production process through proper methods can produce PUs that are suitable for varied specific applications. The present study aims to shed light on the chemistry, types, and synthesis of different kinds of PUs. Some of the important research studies relating to PUs, including their synthesis method, characterization techniques, and research findings, are comprehensively discussed. Herein, recent advances in new types of PUs and their synthesis for various applications are also presented. Furthermore, information is provided on the environmental friendliness of the PUs, with a specific emphasis on their recyclability and recoverability.

Effects of Surface Modification on Dispersion, Mechanical, Thermal And Dynamic Mechanical Properties Of Injection Molded PLA-hydroxyapatite Composites

Abstract: In this study, poly(lactic acid) (PLA)/hydroxyapatite (HA) composites were produced through extrusion and injection moulding. In order to foster good interaction between PLA and HA, a phosphate based modifier (Fabulase(R) 361) was used to modify the HA surface. Spectroscopic analysis reveals that surface of the HA was effectively modified without changing the HA into another material. Morphological study shows effective dispersion of HA in the PLA matrix after modification, with significant influence on the composite properties. Thermal properties of the modified HA composite was improved, alongside an enhancement of about 25%, 20% and 42% in tensile, modulus and impact properties of the modified PLA-HA composite respectively. Furthermore, dynamic properties of the modified HA composite was notably improved with obvious reduction of the damping factor. Thus, surface modification was effective to enhance dispersion and compatibility of HA and PLA to produce polymeric biomaterials suitable for good load bearing applications.

Impact modified PLA-hydroxyapatite composites – Thermo-mechanical properties

Abstract: Synergistic composites from poly(lactic acid) (PLA) and hydroxyapatite (HA) hold great potential for load bearing applications. In this study, PLA-HA composites were produced through extrusion, and test specimens were subsequently prepared through injection molding. Impact properties of the composite was improved by incorporating different amount (0 to 15 wt%) of Biomax® Strong 120 (BS) impact modifier. The mechanical, thermal, morphological and dynamic mechanical properties of the resulting composite were investigated. Likewise, chemical interactions during blending were investigated through Fourier transforms infrared spectroscopy. Incorporation of BS decreased the crystallization activities at the PLA-HA interface, but with a right shift in crystallization temperature as the BS content increases. Also with increasing BS content, mechanical properties of the PLA-HA composite were reduced. However there is an obvious increment in impact strength (78%) and elongation at break (206%). The composite containing 5 wt% BS content presents the best compromise among the investigated properties.

Effects of the filler loading and aging time on the mechanical and electrical conductivity properties of carbon black filled natural rubber

Abstract: The effects of the filler loading and aging time on the mechanical and electrical conductivity properties of natural rubber were investigated. In this work, carbon black (type N220) was used as a filler, and its loading was varied from 0 to 50 phr. The mechanical properties (e.g., the tensile strength and catastrophic tearing energy) increased with a filler loading up to a certain loading, and a decrease in the mechanical properties was observed with higher filler loadings. The tensile strength and catastrophic tearing energy of the aged samples decreased after 3 and 6 days of aging at 100°C. The results for the electrical conductivity properties of unaged samples showed a percolation threshold at 20 phr, and the values were consistent with further filler loadings. After aging, the percolation threshold was still maintained at 20 phr. The morphologies of unaged and aged samples were significantly different: holes were observed to occur in the aged samples. This might have been due to the movement of fillers when the materials were subjected to heat, and this subsequently influenced the mechanical properties of the natural rubber composites. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Preparation and Characterization of Poly(lactic acid)-Based Composites Reinforced with Poly Dimethyl Siloxane/Ultrasound-Treated Oil Palm Empty Fruit Bunch

Abstract: Oil palm empty fruit bunch fiber and polylactic acid were used to produce composites by melting cast method. Fiber loading was considered up to 40 wt%. Oil palm empty fruit bunch fibers were treated using ultrasound and polydimethylsiloxane to improve the interfacial adhesion. The structure and surface properties of the fibers were analyzed by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and contact angle measurement. Moreover, Fourier transform infrared spectroscopy, tensile, flexural, X-ray diffraction, contact angle, differential scanning calorimetry, and thermogravimetric analysis were used to investigate composites’ properties. The analysis revealed that polydimethylsiloxane treatment composites show reduced wettability with increased crystallinity.

Polyurethane types, synthesis and applications – a review

Abstract: Polyurethanes (PUs) are a class of versatile materials with great potential for use in different applications, especially based on their structure–property relationships. Their specific mechanical, physical, biological, and chemical properties are attracting significant research attention to tailoring PUs for use in different applications. Enhancement of the properties and performance of PU-based materials may be achieved through changes to the production process or the raw materials used in their fabrication or via the use of advanced characterization techniques. Clearly, modification of the raw materials and production process through proper methods can produce PUs that are suitable for varied specific applications. The present study aims to shed light on the chemistry, types, and synthesis of different kinds of PUs. Some of the important research studies relating to PUs, including their synthesis method, characterization techniques, and research findings, are comprehensively discussed. Herein, recent advances in new types of PUs and their synthesis for various applications are also presented. Furthermore, information is provided on the environmental friendliness of the PUs, with a specific emphasis on their recyclability and recoverability.

Biomass and bioenergy

Abstract: Plant biomass are woody and non-wood materials (e.g., oil palm, bamboo, rattan, bagasse, and kenaf) and are abundant and renewable resource. Unfortunately, the heavy reliance on this resource is a threat to forest ecosystems and a recipe for accelerated land resource degradation. Due to the increasing scarcity of wood resources, many rural communities have shifted to utilization of crop residues for many different applications. The non-wood biomass is readily available, environmental friendly, and technologically suitable, and therefore, an excellent raw material for the future. The non-wood materials like bamboo, rattan, oil palm, and bagasse have superior properties and durability, which can be further prolonged by the modifi cation treatment. The modifi cation treatments increase the performance of the non-wood and could make it suitable for applications in many fi elds ranging from construction industry to automotive industry. This chapter deals with the properties improvement techniques of the selected non-wood biomasses and evaluates its applications for various purposes. The new developments dealing with the improvement of non-wood properties have also been presented in the chapter. The performance of non-wood biomass materials has been compared to the wood-based materials. Recent studies pertaining to the above topics have also been cited. Finally, the advanced applications of the improved non-wood biomasses have been highlighted.

Material-Based Approaches for the Fabrication of Stretchable Electronics.

Abstract: Stretchable electronics are mechanically compatible with a variety of objects, especially with the soft curvilinear contours of the human body, enabling human-friendly electronics applications that could not be achieved with conventional rigid electronics. Therefore, extensive research effort has been devoted to the development of stretchable electronics, from research on materials and unit device, to fully integrated systems. In particular, material-processing technologies that encompass the synthesis, assembly, and patterning of intrinsically stretchable electronic materials have been actively investigated and have provided many notable breakthroughs for the advancement of stretchable electronics. Here, the latest studies of such material-based approaches are reviewed, mainly focusing on intrinsically stretchable electronic nanocomposites that generally consist of conducting/semiconducting filler materials inside or on elastomer backbone matrices. Various approaches for fabricating these intrinsically stretchable electronic materials are presented, including the blending of electronic fillers into elastomer matrices, the formation of bi-layered heterogeneous electronic-layer and elastomer support-layer structures, and modifications to polymeric molecular structures in order to impart stretchability. Detailed descriptions of the various conducting/semiconducting composites prepared by each method are provided, along with their electrical/mechanical properties and examples of device applications. To conclude, a brief future outlook is presented.

Hydrothermal carbonization of lignocellulosic biomass for carbon rich material preparation: A review

Abstract: Hydrothermal carbonization (HTC) is an active area of research in synthesizing carbon-rich materials because of its ability to transform wet biomass into valuable products. Carbon-rich materials have received a great deal of attention because carbon is a raw material for several industrial products and their production from various biomasses is currently an active area of research. In addition, lignocellulosic biomass has been of great interest as precursors for the preparation of carbon-rich materials because of their low cost and due to environmental concerns. This review exhibits the research on the hydrothermal carbonization of lignocellulosic biomass, production of carbon-rich materials or carbon spheres or hydrochar by the HTC process and the role of water and the proposed mechanism in the HTC process. This research on hydrothermal carbonization mostly focused on lignocellulosic biomass materials and the effect of process parameters including the temperature, pressure residence time, pH, heating rate and substrate concentration are also discussed. The reaction mechanisms of hydrolysis, dehydration or decarboxylation and carbonization are elaborated in detail. Solid carbon-rich materials have a wide range of applications as environmental additives, biofuels, catalysts and energy storage and have been covered in detail. At the end of the review, we deliver an outlook on future research prospects and applications of hydrothermal carbon-rich materials.