Mokgaotsa Jonas Mochane

The effect of expanded graphite on the flammability and thermal conductivity properties of phase change material based on PP/wax blends

The study reports on the flammability, thermal stability, impact properties and thermal conductivity of shape-stabilized phase change materials based on a soft Fischer–Tropsch paraffin wax blended with polypropylene (PP). The blends were melt-mixed with expanded graphite (EG) up to 9 wt% to improve the thermal conductivity and flammability resistance of the material. The thermal stability and flammability results show an increase in thermal stability and flame resistance of PP in the presence of EG, with the flammability further increasing in the presence of wax, probably because of the smaller and better dispersed EG particles in the PP/wax/EG composite that gave rise to a more compact char layer. Although the thermal degradation mechanism did not change in the presence of EG, the EG particles retarded the evolution of the volatile degradation products. The storage modulus of the PP/wax/EG composite was lower than those of PP and PP/EG, and decreased with increasing in wax content because of the softening effect of the wax. The impact strength of the PP/wax/EG composites increased with increasing EG content in all the samples, but decreased with increasing wax content.

In-situ Polymerization of Nylon-Cellulose Nano composite

Polymeric Nano composite has been strongly studied due to the improvement achieved when a little amount of Nano sized particles are added to the polymer matrix. This is primarily due to large surface area which increased the interaction between the nanoparticles and the polymer. There are different routes for preparation of the polymer Nano composite with Nano fillers it can be melt compound, in-situ polymerization and the solvent method. The in-situ method was found to be best method due to that the nanoparticle is introduced directly to the monomer and it allowed for few minutes to disperse well to the monomer before the initiator is added to start polymerization. The in-situ method gives control over the particle size and morphology. The present studies investigate the surface morphology and thermal properties of nylon when the cellulose Nano-whiskers of different content was added into nylon monomer. SEM for surface studies, TGA for thermal stabilities and FTIR for chemical properties were studied. TGA results reveal that nylon thermal properties changes with addition of Nano crystals compared to pure nylon.

Systematic review on recent studies on sugar cane bagasse and bagasse cellulose polymer composites

Sugar cane bagasse (SCB) is one of the abundant and available natural fibres in many countries as a by-product from sugar cane mills after an extraction of sugar. Attempts have been made to convert this by-product into useful eco-friendly cement-bonded composites and polymer composites, which can be used for various internal and external applications in buildings. Some researchers extracted cellulose from SCB and incorporated it in different polymeric matrices. The investigations included optimization of parameters and chemical treatments such as bagasse content or coupling agents for a production of effective composites. The influence of different parameters on the setting of the composite material such as botanical components of the fibre, thermal or chemical treatment of the fibre and bagasse fibre content have shown enhancement in properties. The recent work cited in this review suggests that SCB can be used to prepare fibre-reinforced polymer composites for commercial use. Furthermore, there seems to be a little research done on the application of SCB nanocellulose–polymer composites. In fact, this review discusses the current state of SCB as filler in polymer composites with citation of the latest research. It furthermore exposes more research options for SCB and its ash.