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Bismaleimide (BMI) is a kind of thermosetting resin and its application is usually limited by low toughness. In this paper, two kinds of reinforcement intercalator amino-terminated polyoxypropylene (POP) and octadecyl trimethyl ammonium chloride (OTAC) were designed and synthesized to toughen BMI resin and the toughening effect was compared and analyzed. The purpose of this paper is to toughen BMI resin and analyze the toughening effect of two reinforcements intercalator amino-terminated polyoxypropylene (POP) and octadecyl trimethyl ammonium chloride (OTAC).

Sodium-based montmorillonite (Na-MMT) was modified by POP and OTAC, and the ion-exchange reaction obtained organic montmorillonite (POP-MMT and OTAC-MMT). The polymer matrix (MBAE) was synthesized, in which 4,4’-diamino diphenyl methane BMI was used as the monomer and 3,3’-diallyl bisphenol A and bisphenol A diallyl ether were used as active diluents. And then, POP-MMT/MBAE and OTAC-MMT/MBAE composites were prepared using MBAE as matrix and POP-MMT or OTAC-MMT as reinforcement. The Fourier-transform infrared, X-ray diffraction and scanning electron microscope (SEM) of the filler and microstructure and mechanical properties of the composite were characterized to the better reinforcement.

POP-MMT and OTAC-MMT enhanced BMI-cured products’ toughness by generating microcracks in the polymer to absorb more fracture energy. Meanwhile, POP-MMT and OTAC-MMT were the main stress components and the enhancement of the interface interaction was beneficial to transfer the external force from the matrix to the reinforcement and improved the mechanical properties of the composite. Furthermore, with the intercalation rate increasing, the compatibility of the two phases was increased and the performance of MBAE was also elevated.

BMI is generally used as aerospace structural materials, functional materials, impregnating paint and other fields. However, high crosslinking density leads to moulding material’s brittleness and limits a wider range of applications. Therefore, it has become an urgent priority to explore and improve the mechanical properties of BMI resin.

POP and OTAC have successfully intercalated Na-MMT layers to get POP-MMT and OTAC-MMT, and the interplanar crystal spacing and the intercalation rate were calculated, respectively. The results were corresponding with the SEM images of POP-MMT and OTAC-MMT. After that, the morphology of composites illustrated the compatibility was related to the intercalation rate. According to the mechanism of modified MMT toughening epoxy resin, when they were dispersed uniformly in the matrix, the composite’s mechanical properties had been significantly improved. Additionally, OTAC-MMT with a higher intercalation rate had better compatibility and interfacial force with the matrix, so that the mechanical properties of OTAC-MMT/MBAE were the best.

Activism in the sport world is often connected to iconic images like the raised fists of John Carlos and Tommie Smith in a Black Power salute at the 1968 Mexico City Olympics or the figure of Cathy Freeman, wrapped in the Aboriginal flag, taking her victory lap at the 1994 Commonwealth Games and the 2020 Sydney Olympics. Activism, be it individual or through collective action, is a contemporary reality in sport. These actions reverberate out, sometimes joining with or magnifying other significant social and political currents to create waves that shift society. They may take the form of supporting mental health conversations, developing sporting infrastructure and support to expand opportunities for the next generation, concerted efforts at changing governance representation, or challenging sexist policy in sports, for example. This chapter draws from a talanoa on activism in Pacific sport, bringing these various activities together in order to surface the activism taking place, and better understand and reframe how we think about sport activism in Pacific communities. On the one hand, we recognize that particular cultural values like humility, respect, and orientations to servant leadership naturally encourage activism in the form of everyday advocacy and grassroots interventions. On the other, we discuss whether these values also prevent more outspoken and disruptive forms of activism which are often required to challenge systems of injustice and enact structural change. In this preliminary look at Pacific activism in sport, we surface some insights and raise questions for future research.

This case deals with the need of a European company to import organic soybean from India. The company's India Operations Manager wants to know the feasibility of such a venture. The case describes the procurement of organic soybean from a city in central India, understanding standards of organic production, and finally the costs and procedures involved in exporting the organic soybean to Europe.

This paper aims to look at a key trend shaking up universal service policy around the world – the emergence of mobile and wireless technologies as a central feature of telecommunications and convergent media.

The paper reviews the development of mobiles, and how they fit into the evolution of approaches to universal service. It then considers different facets of what mobiles represent for universal service, including the expansion of universal service, the relationship of access to universal service, spectrum management, and the user and innovation. The paper seeks to integrate these aspects into a consolidated account of what mobiles represent for universal service.

The paper finds that mobiles are providing timely access to basic telecommunications, and so we need to reconfigure the apparatus of universal service to acknowledge and build upon this. It finds also that there is a strong case for building mobility into definitions of universal service. Accordingly the paper advocates an evolution of the universal service concept to include mobility. In particular, there is a need for the role of mobile data, internet, and mobile media services to be evaluated – and thought about as part of the general policy discussions about building broadband platforms, and ensuring user access to and use of these. It suggests that there is now a rationale for explicitly giving an account of mobility in policies inspired by and relating to universal service. It recommends great adoption of new approaches to universal service, through flexible and open spectrum management, and also through policies that foster commons approaches. Finally, the paper suggests that stronger and more purposeful links be drawn between universal service and policies aimed at fostering innovation and at enabling and harnessing users (such as citizenship, cultural policies, and digital literacy).

The value of this paper lies in its dedicated focus on mobiles, and their implications are for rethinking universal service. To do so, the paper particularly draws upon user perspectives.

This paper aims to study the role of organobentonite (OB) as a filler to improve the mechanical strength of styrene butadiene rubber (SBR). Organoclay was first prepared by modifying bentonite with different concentrations of N-cetyl-N, N, N-triethyl ammonium bromide. A series of SBR composites reinforced with OB were prepared using master-batch method.

The curing characteristics, mechanical properties, thermal behavior, dielectric properties and morphology of SBR/OB composites were investigated.

The elastic modulus and tensile strength of composites were increased by inclusion of OB, while the elongation at break was decreased, due to the increase in the degree of cross-linking density. Thermal gravimetric analysis revealed an improvement in the thermal stability of the composite containing 0.5 cation exchange capacity (CEC) OB, while the scanning electron micrographs confirmed more homogenous distribution of 0.5CEC OB in the rubber matrix. Also, SBR/0.5CEC OB showed low relative permittivity and electrical insulating properties.

Bentonite has been recognized as a potentially useful filler in polymer matrix composites because of their high swelling capacity and plate morphology.

OB improves the cured rubber by increasing the tensile strength and the stiffness of the vulcanizate.

Using cheap clay in rubber industry lead to production of low cost products with high efficiency.

The clay represents a convenient source because of their environmental compatibility. The low cost and easy availability make the modified clay used as fillers in rubber matrices, and the resultant composites can be applied in variety industrial of applications such as automobile industries, shoe outsoles, packaging materials and construction engineering.

This study aims to investigate the mechanical, thermal, melt-flow and morphological behavior of acrylonitrile-butadiene-styrene (ABS)-based composites after bentonite inclusions. Melt mixing is the most preferred production method in industrial scale and basically it has very near processing parameters compared to 3D printing applications. Rheological parameters of ABS and its composites are important for 3D applications. Melt flow behavior of ABS effects the fabrication of 3D printed product at desired levels. Shear thinning and non-Newtonian viscosity characteristics of ABS make viscosity control easier and more flexible for several processing techniques including injection molding, compression molding and 3D printing.

ABS copolymer was reinforced with bentonite mineral (BNT) at four different loading ratios of 5%, 10%, 15% and 20%. ABS/BNT composites were fabricated by lab-scale micro-compounder followed by injection molding process. Mechanical, thermo-mechanical, thermal, melt-flow and morphological properties of composites were investigated by tensile, hardness and impact tests, dynamic mechanical analysis (DMA), thermo-gravimetric analysis (TGA), melt flow index (MFI) test and scanning electron microscopy (SEM), respectively.

Mechanical tests revealed that tensile strength, elongation and hardness of ABS were enhanced as BNT content increased. Glass transition temperature and storage modulus of ABS exhibited increasing trend with the additions of BNT. However, impact strength values dropped down with BNT inclusion. According to MFI test measurements, BNT incorporation displayed no significant change for MFI value of ABS. Homogeneous dispersion of BNT particles into ABS phase was deduced from SEM micrographs of composites. Loading ratio of 15% BNT was remarked as the most suitable candidate among fabricated ABS-based composites according to findings.

The advanced mechanical properties and easy processing characteristics are the reasons for usage of ABS as an engineering plastic. Owing to the increase in its usage for 3D printing technology, the ABS became popular in recent years. The utilization of ABS in this technology is in filament form with various colors and dimensions. This is because of its proper rheological features.

Melt-mixing technique was used as preparation of composites, as this processing method is widely applied in industry. This method is also providing similar processing methodology with 3D printing technology.

According to the literature survey, to the best of the authors’ knowledge, this study is the first research work regarding the melt-flow performance of ABS-based composites to evaluate their 3D printing applications and processability. ABS and BNT containing composites were characterized by tensile, impact and shore hardness tests, DMA, TGA), MFI test and SEM techniques.