Accelerated curing of high performance fibre-reinforced polymer (FRP) composites via microwave heating or radiation, which can significantly reduce cure time and increase energy efficiency, has several major challenges (e.g. uneven depth of radiation penetration, reinforcing fibre shielding, uneven curing, introduction of hot spots etc). This article reviews the current scientific challenges with microwave curing of FRP composites considering the underlying physics of microwave radiation absorption in thermoset-matrix composites. The fundamental principles behind efficient accelerated curing of composites using microwave radiation heating are reviewed and presented, especially focusing on the relation between penetration depth, microwave frequency, dielectric properties and cure degree. Based on this review, major factors influencing microwave curing of thermoset-matrix composites are identified, and recommendations for efficient cure cycle design are provided.

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This paper investigated the effects of calcium cabonate nanofiller on the mechanical behavior of homo polypropylene by conducting tensile and creep tests. The Young's Modulus of the nanocomposite showed some improvement with the incorporation of the calcium carbonate nano-filler while the tensile strength deteriorated. The stearic acid coated fillers showed the highest improvement in the above tensile properties at low volume fractions not exceeding 0.10 while the deformation rate increases with the inclusion of the nanofiller. The creep parameters evaluated include optimum elastic modulus estimated as 2GPa at 10% volume fraction, creep rate at ambient as 0.004-0.043hr -1 , and creep limit at ambient as 60-113MPa as opposed to the tensile strength of PPC predicted as 45MPa for treated and 37.5MPa for untreated, all as against 123MPa for neat and unreinforced PP, though at 0.05 volume fraction the tensile strength was evaluated as 140MPa and 133.3MPa for coated and uncoated PPC respectively.

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Kaolin was modified using a chemical complex of hydrazine hydrate and oleochemical sodium salts derived from rubber seed oil (SRSO) and tea seed oil (STSO) respectively. Characterization of the pristine kaolin and the modified kaolins were performed using Scanning Electron Microscopy (SEM), Simultaneous Thermogravimetric/Differential Thermal Analysis (TG/DTA) and UV Spectrophotometry. TG/DTA revealed that the incorporation of the oleochemical salts enhanced thermal decomposition of kaolin into metakaolin. Ultraviolet spectrophotometric studies conducted on the modified kaolin show for the first time that the SRSO-modified kaolin and STSO-modified kaolin have a peak absorbance wavelengths of 312.72 nm and 314.26 nm respectively. This shows that the modified kaolin is a promising candidate for sunscreen applications.

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