Waste cooking oils are problematic to dispose of especially in the developed countries. In this paper, waste cooking oil is used as raw material to produce foam. The purpose of this study is to develop a high density solid biopolymer foam (HDB) by using a hot compression molding technique based on flexible and rigid cross-linking agents. Physical properties such as scanning electron microscopy (SEM) and vibration characteristics have been studied using a vibration transmissibility test according to the ASTM D3580-95 standard. Different thicknesses were examined during the fabrication of HDB to measure the vibration property. By using the linear vibration theory with a single degree of freedom, the resonance frequency of vibration transmissibility and damping ratios of HDB foam at variation excitation are acquired. The results show that HDB flexible foam gives a higher damping ratio to absorb vibration. The capability of the HDB flexible foam to absorb vibration is greater than rigid HDB. It was observed that no improvement was achieved by increasing the thickness of HDB to vibration transmissibility. Reducing the thickness of the HDB flexible foam gives an increment of a damping ratio up to 36%.

Purpose The purpose of this study is to conduct an investigation into the potential characteristics of Pistia stratiotes at different maturity stages. The focus of interest was to specifically look at oleophilicity properties based on contact angle (CA) measurement. Design/methodology/approach The morphological characteristics were also examined using a variable pressure scanning electron microscope. Three different oils, namely, Bio Oil 1, Bio Oil 2 and MP-R 10W/40 semi-synthetic oil, were tested on the Pistia leaf surface to measure the CA and wetting properties. Findings It was found that both types of bio oils had distinct CA values compared to that of the synthetic oil. A maximum difference of 65° to 75° was recorded in CA values. Originality/value Based on the results, the maturity of leaves was found to affect the CA values.

The demand for bio-polymer compound (BPC) has attracted attention in various applications from industrial to medical. Therefore, the mechanical and thermal stability properties of recycling industrial waste BPC are very important to investigate. The waste BPC for this study is based on a mixture of hydroxylated waste cooking oil with hardeners to produce waste bio-polymer foam (WBF). The granulate of WBF was cast into the mold until all spaces were evenly filled and compacted into a homogeneous shape and thickness at 30-45 bar for 2 hours using hot compression molding. This method of BPC fabrication results in a tensile and flexural strength of 4.89 MPa and 18.08 MPa respectively. Meanwhile, the thermal stability of laminated BPC was conducted using a thermal gravimetric analyzer (TGA), and the first degradation of the soft segment occurred at 263°C, then subsequently the second degradation occurred at 351°C and the last at 416°C.

Learning mathematics is associated with the assumption as a killer subject that are struggled by many students. This subject is not strictly for one particular field but learners are coming from different disciplines as well. Differences between the disciplines in education may results in difference motivation towards learning mathematics. Thus, this study aims to investigate the motivation of learning mathematics across three disciplines, science and technology, social sciences and business. This quantitative research was conducted by distributing a set of questionnaires to 234 students in a public university in Malaysia. The instruments from the questionnaire with a total of 24 items, consisted of three sections, namely, affective components, expectancy components and value components. The findings reported that learners from social science showed higher mathematics anxiety compared to science and technology and business students yet, it was also a positive attitude to encourage themselves to do better in Mathematics as they believe they can excel in Mathematics. In addition, data presented that learners from Social Science and Business priorities in achieving a good grade to show their ability to others. Eventually, this study provides an insight for the educators towards learners' motivation from different disciplines to learn Mathematics as well as helps educators to provide a suitable treatment and improve teaching quality to students according to their disciplines. In addition to that it is also hoped that the findings of this study add to the existing theoretical framework in the motivations for learning in general and specifically for motivations in the learning of Mathematics.

Synthetic polymer such as polyethylene is used widely in industry, agricultures and daily life owing to its relatively low price and good mechanical and processing properties. These synthetic polymers are, however, often not environmentally friendly because they typically do not undergo the process of biodegradation and, of course, are dependent on a limited petroleum resource. Therefore, concerns on environmental problems caused using of non-degradable petrochemical polymers have caused an increasing interest in degradable polymers especially biopolymers from crop plants. Biopolymers have much potential and several advantages, but they possess some drawbacks as well. Despite increasing production capacity, they are still quite expensive compared to commodity polymers and their properties are also often inferior, or at least do not correspond to the expectation of converters or users. This concept has led to the development blending of biopolymer and High-Density Polyethylene (HDPE). In this study, 5, 10, 15, 20, 25 and 30% of Biopolymer (BP) was blended with HDPE known as BBP5, BBP10, BBP15, BBP20, BBP25 and BBP30 were prepared by melt-mixing process by using Brabender Plastograph® EC machine. BBP5, BBP10, BBP15, BBP20, BBP25 and BBP30 then were exposed in UV weatherometer by using UV Lamp Test Chamber Model HD-703 at different UV exposure, which is 250h, 500h, 750h,1000h, 2000h, and 3000h. Physical properties and photodegradation mechanism development of BBP5, BBP10, BBP15, BBP20, BBP25 and BBP30 were examined by means of Fourier Transform Infrared (FTIR) at different UV exposure. The photodegradation mechanism of BBP5, BBP10, BBP15, BBP20, BBP25 and BBP30 shows relationship with the Norrish type I and Norrish type II reaction as indicated the possibilities of blended polymer degradation process was occurred.