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This paper presents the development of bipolymer nanopolymers - polyamide and polyethylene - compatibilised with polyethylenegraft- maleic anhydride and graphite nanoparticles. Polyamide/polyethylene (PA/PE) composites are studied because both components are relatively inexpensive, advantageous and are processed by injection. Compatibilisation of binary polymer compounds can be accomplished by adding a grafted copolymer, the segments of which have physical or chemical affinity with the two immiscible homopolymers. In this case, polyethylene-graft-maleic anhydride (PE-g-MA) was used. Graphite-containing polymer composites are considered a new generation of materials with predefined properties, in this case, resistance to impact. The combined effects of graphite and compatibilizing polymer (PE-g- MA) were studied on the structure and properties of the new materials. The tested nanocomposites were characterized morpho-structurally (SEM, FT-IR spectrometry) and physico-mechanically. [ABSTRACT FROM AUTHOR]

ATH filled NR/PP thermoplastic vulcanisates (TPVs) were obtained from blending natural rubber (NR), polypropylene (PP) and alumina trihydrate (ATH) by using Brabender plastograph. Maleic anhydride grafted polypropylene (MAH-g-PP) was used as compatibiliser to improve mechanical and flammability properties of TPVs. The effect of MAH-g-PP at different concentrations on the properties of ATH filled NR/PP TPVs was studied. Investigation on the microstructures of ATH filled NR/PP TPVs by mean of scanning electron microscope (SEM) and transmission electron microscope (TEM) indicated the efficient mixing of NR and PP phases and more uniform distribution of ATH in individual component of NR/PP blend due to compatibilising action of MAH-g-PP. Mechanistic model for the compatibilisation process of a structure of ATH filled NR/PP TPVs in the presence of MAH-g-PP was also proposed. With higher concentration of MAH-g-PP, the TPVs had shown increase in 100% modulus, increase in tensile strength, decrease in elongation at break and less elastic recovery. The flame resistance also increased with the addition of given amount of MAH-g-PP. However, the addition of MAH-g-PP had little influence on processing capability of the ATH filled NR/PP TPVs. Based on the present study, it was suggested that the MAH-g-PP acted as compatibility enhancer in the ATH filled NR/PP TPVs and the compatibility increase was a key to benefit the strength and flame retardancy of the NR/PP TPVs. [ABSTRACT FROM AUTHOR]

The use of natural fibres in the development of composite materials is a sector in full expansion. These fibres were used for their low cost, availability and renewable character. The fibres of the palm (palm tree) were used as reinforcement in polypropylene. The date palm fibres have some potential because of their ecological and economic interest. Both unmodified and compatibilised fibres are used. Compatibilisation was carried out with the use of maleic anhydride copolymers. The morphology and mechanical properties were characterised by scanning electron microscopy and tensile tests. The influence of fibre content on mechanical properties of composite polypropylene/date palm has been evaluated and demonstrated that the maximum stress and elongation decreases with increasing fibre content, on the contrary, they notice an increase of the tensile modulus, but after the improvement of fibres, the maximum stress increase significantly up to 25% weight. [ABSTRACT FROM AUTHOR]

Natural weathering was performed on poly(butylene succinate) (PBS) and its kenaf bast fibre (KBF) filled composites by exposing the specimens to a tropical climate for a period of 6 months (max-min temperature: 31.5-23.9 °C; relative humidity: 78.9%). The aim of this study was to investigate the effects of KBF loading and the addition of maleated PBS compatibiliser (PBSgMA) on the performance of the composites under natural weathering. As expected, the flexural properties of both the uncompatibilised and compatibilised composites dropped with increasing exposure time. The weathered specimens were also assessed by colour change analysis, FTIR spectroscopy analysis and SEM examination. The total colour change, ΔE, of both the uncompatibilised and compatibilised composites increased with weathering time. FTIR spectroscopy analysis confirmed the presence of oxidation products such as hydroxyl, carbonyl and vinyl species in the weathered uncompatibilised and compatibilised composites. SEM examination revealed the presence of surface defects such as cracking, tiny holes and degraded fibre, which explain the poor performance of the composites upon weathering. [ABSTRACT FROM AUTHOR]