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Development of the Polymer Composites with natural fibers and fillers as a sustainable alternative material for some engineering applications, particularly in aerospace applications and automobile applications are being investigated. Lightweight and biodegradability and low cost Polyester composites are synthesised with an addition of Silicon carbide (SiC) particles by varying weight percentage (0, 3, 6, 10, 13, and 16 wt. %) respectively by using hand- layup technique followed by cold moulding. The prepared specimens were cut according to ASTM standard to determine hardness, impact strength, bending distortion and thermal conductivity properties. Afterward, the thermal and mechanical properties of all the unfilled and particulate filled composites are also evaluated for structural applications, i.e., hardness, impact strength, bending distortion, are determined with the change in filler content to notice the behaviour of composite material subjected to loading in addition to thermal conductivity property. Thermo-mechanical properties of the material are measured with the help of testing machines above according to their ASTM. It is found that the strength properties are greatly influenced by addition of this ceramic filler. Also shows that the thermal and mechanical properties of SiC-filled polyester composites are better than unfilled base composites

Dental amalgam is a mixture of approximately 50% mercury and varying ratios of silver, tin, zinc, and copper. Dental amalgam is a major source of mercury pollution because it is readily absorbed through 90-100% vapour and the oral mucosa. In addition, in certain situations with the oral environment, various types of metallic orthodontic brackets are highly aggressive and can lead to corrosion. However, polyvinyl alcohol (PVA) material has no cytogenetic effects on human health or the environment and is therefore applied in the manufacturing of the new composite material. Different additives from the bonding agent (PVA; 2.4, 4.8, and 7.2 g)  dissolved in about 10 ml of water, heated on a hot plate under a high-temperature heat treatment (150-200 á´¼C), and continuously stirred for about 20 minutes, until all the PVA dissolved or the solution became colorless. Subsequently, a fixed amount of powdered amalgam (2.4g) added after the mercury content was separated. It was continuously mixed until it reached a homogenous solution, then molded and cured to give the final product. New samples were used for the following purposes: (1) to investigate their effects on the chemical, thermal and mechanical properties of the composite samples, (2) composite scanning and images from the EDS diffraction. Scanning lectron microscopy (SEM) indicated that the presence of the methyl group (CHI) that lowers the crystallinity of PVA, also forms bridges between the different chains obtained to indicate the suitable materials for guided dental applications.

The quantity and type of waste being generated is growing at enormous rate. The plastic waste produced particularly in form of bags, Plates, Containers, being nondegradable and with limited recycling options poses disposal problem. An academic research aimed at probable use of waste plastic in pavement structure so as to come up with an ultimate safe disposal together with improvement in the performance of asphalt mix of road through better mix design was under taken.Preliminary investigations have indicate of RPWA (from 1.2 in (1.5 cm) to No. 200 sieve ( 0.075 cm) , in surface mix design when utilized up to (5% to 15%) by weight substitution, through the use of Box-Wilson design program in order to give an optimum condition, time of reaction, and weight percent of substitution replacement aggregate in asphalt mix. The above following variables were studied temperatures (109-206) c ο , time (20-60) min and weight at waste substitution (5-15) % wt. respectively. The optimum conditions were: were 172 o c, 40 min, and 10% wt RPWA.The effects of experimental variables on the properties of improved asphalt mix were studied using the Box-Wilson technique of experimental design and useful relationships could be attained. Which improved these optimum conditions give high stability of Marshall Test and low distortion with acceptable low constant wet density and uneffect dry density with these condition with high resistance to chemical solutions exposure? It is envisaged that use of RPWA in the conventional asphalt hot mix design likely to improve the surface asphalt mix performance with sustainable solution for the disposal of plastic waste.

The high performance and unique utilization properties applied by designers according to improvement of thermal and mechanical products were reinforced by particulate materials. The present study deals with the preparation of a composite system (EP/PVC). afterward the estimation of thermo-chemical behaviour of epoxy composite (EP/PVC) reinforced by addition of micro-fillers particulate of waste scrap tires (WST). Three different sets of epoxy-PVC composites are fabricated with addition of 0, 0.25, and 0.4 wt% of WST particulates. These composites have been prepared and both chemical reactivity absorbance and thermal conductivities are achieved. From results it appeared that a decreasing in thermal conductivity values about 55 % for 0.25wt % for a micro-WST of epoxy composite system, of 0.4wt. %recorded decreasing of thermal conductivity at88 %when compared to epoxy composite system (EP/PVC). The results show that the (WST) microfillers particles show an insulation polar behaviour at 0.4 wt. % at which a random behaviour in thermal conductivity is recorded .In addition to an experimental examination of chemical activity absorbance for both composite system before and after additive of micro-filler particulate of waste scrap tires (WST) in different soaking medium (normal and acidic solutions) and different residence times (0-120 hrs) respectively. The results proved that an improvement chemical activity occurred for optimum sample no. 3 of (2.5/ .4 + .4 (EP/PVC + WST) that have minimum loss in weight as (0.001) under both soaking medium (100% H 2 O, 10% H 2 SO 4 ) rather than base composite system (EP/PVC) and other improved one of .25 wt. % from WST of (0.01 -0.05) respectively.