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The improvements of the thermal, mechanical, morphological properties of low-density polyethylene (LDPE)/nanoclay (NC) composites were investigated. Low-density polyethylene (LDPE) with different NC contents 2 wt.% ( Vf= 8%), 4 wt.% ( Vf= 15), and 8 wt.% ( Vf= 27) with a fixed particle size (300μm) were prepared by the melt mixing process. The thermal tests (thermal gravimetric analysis) were performed to monitor the thermal stability of LDPE composites. The mechanical tests such as tensile strength, Young’s modulus, and strain at break were studied. The results of the thermal gravimetric analysis (TGA) display significant enhancement in thermal stability as the loading of NC increased in pure LDPE. The results showed that the NC fillers could effectively improve the mechanical properties of LDPE by comparison to pure LDPE, the tensile strength of LDPE/8 wt.% of NC are increasing by about 17% while Young’s modulus is increased by about 39%. From DMA results, the storage modulus is enhanced with increasing of NC loading into the LDPE matrix. The results of SEM photographs indicate that the incorporation 8 wt.% of NC displayed the best particles dispersion in the LDPE matrix.

The influence of exposure to UV light and moisture on the durability of a multiwalled carbon nanotube(MWCNT)/epoxy nanocomposite was investigated. Samples of epoxy resin based on diglycidyl ether of bisphenol A (DGEBA) cured with 2,2,4-trimethylene-1,6-hexadiamine (TMDA), and epoxy nanocomposite containing 0.5% MWCNT were exposed to different accelerated weathering times between one and six months. Changes in surface chemistry, mechanical properties (tensile tests), thermal properties (thermogravimetric analysis and differential scanning calorimetry), and morphology were evaluated before and after exposure to accelerated weathering for a period of up to six months. Epoxy nanocomposite (DGEBA–TMDA/0.5%MWCNT) samples had improved thermal stability and resistance to degradation, compared to epoxy resin (DGEBA–TMDA). The effect of MWCNT at reducing degradation was more pronounced than previously found for resins prepared with hydrogenated DGEBA.

Accelerated weathering of polyvinyl alcohol (PVA) and PVA reinforced with 20 wt% of zinc chloride (ZnCl2) was investigated. The developed PVA composites were subjected to 100, 200, and 300 h of accelerated weathering exposure times. The effects of exposure on the PVA composites were characterized by Fourier transform infrared (FTIR), thermal properties as thermogravimetric analysis and differential scanning calorimetry, the mechanical and morphology properties, and X-ray diffraction analysis. The results of FTIR displayed that lower carbonyl and hydroxyl indexes are due to PVA composite. The results of mechanical tests showed that the accelerated weathering reduced the tensile strength of PVA. However, PVA composites exhibited fewer reduction of the tensile strength values. PVA composites exhibited better thermal stability after extent to ultraviolet irradiation. The storage modulus from dynamic mechanical analysis results that displayed a higher value for the storage modulus is related to PVA composites, compared to PVA. Before exposure, PVA composite showed a high intensity, compared to PVA. After exposure to accelerated weathering, the intensity of all samples shifted and decreased. Scanning electron microscopic micrographs showed that the surface of the PVA composites had fewer defects compared to the PVA after exposure. The results of characterization revealed that 20% of ZnCl2 into the PVA made less vulnerable to environmental degradation, and these PVA composites are suitable as packaging films for use in outdoor applications.