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Recent developments in advanced polymeric materials and their foams have shown that these novel materials can improve design of newer materials and their processes for various applications from automobile to biomedical systems. Improved processing methodology along with structural stability and multi-functionality are the key factors that dictate the applicability of polymeric materials. The use of segmented thermoplastic polyurethane has not been a popular material choice for rotomolded parts due to high bubble formation, noticeable discoloration and a higher-than-normal occurrence of bridging. Therefore this work focused on understanding the basic material properties and optimization of the processing parameters in order to obtain defect free rotationally molded polyurethane. Obtained results indicates that rotationally molded samples showed no discoloration indicating there is no thermo-oxidative degradation of TPU. No warpage or shrinkage in the molded cube shows that, produced products are dimensionally stable. There was a complete mold filling in the product indicating an optimum time-temperature for coalescence of the TPU particles in the mold. But, bubble formation and pinholes on the product surface are the major issues in the current processing due to the presence of trapped air.

Polymer composites have wide applications owing to their several advantages, which are quite appreciable in the field of science and technology. In the present study, an attempt has been made to investigate the feasibility of Unsaturated Polyester-WO3 polymer composites in radiation protection, through its morphology, shielding ability and mechanical strength. Open mold cast technique was used to fabricate the composites. The WO3 filler particles were distributed and dispersed in the polymer matrix and was ensured through SEM images. The shielding ability of the polymer composites for 662keV gamma rays was studied using Gamma Ray Spectrometry in terms of shielding parameters like attenuation coefficient (µ) and half value layer thickness (HVL). Mechanical properties of the composites were carried out as per ASTM standards as these composites may experience unexpected load during their lifetime. An increasing trend in the attenuation coefficient was observed with the addition of WO3 filler particles and was found to range from 0.087±0.0084 – 0.169±0.0091 cm−1. The HVL value was found to decrease with increase in the filler content and is in the range 7.967 - 4.11 cm. The highest value for µ and lowest value for HVL was observed with 40Wt% of WO3 filled composite. Tensile strength and modulus were also found to increase with increase in the filler content. These were found to range from 16.00 ± 1.05 – 27.24 ± 1.31 MPa and 1.45 ± 0.04 - 1.94 ± 0.05 GPa respectively. Thus, 40Wt% of WO3 filled Polyester based polymer composite exhibit excellent shielding ability and mechanical strength. This study reveals the role of WO3 in enhancing the gamma shielding ability and mechanical strength of the polymer composites. Hence, these composites find their place in the radiation environment where gamma/X ray sources are in use.