IOSR Journal of Applied Chemistry (IOSR-JAC) e-ISSN: 2278-5736.Volume 7, Issue 12 Ver. II. (Dec. 2014), PP 32-44 www.iosrjournals.org www.iosrjournals.org 32 | Page Nanoindentation Behaviorand Physical Properties of Polyvinyl Chloride /Styrene co-maleic anhydride Blend Reinforced by Nano-Bentonite D. E. Abulyazied 1* , S. M. Mokhtar 2 , A. M. Motawie 1 , 1Polymer Laboratory, Petrochemical Dept., Egyptian Petroleum Research Institute, Nasr City, Cairo, Egypt, Postal code: 11727 2Chemistry Dept., College of girls, Ain Shams University, Cairo, Egypt, Postal code: 11715 Abstract: This article studiesthe effects of nano-bentonite on the structure and properties of polymer blends nanocomposites, based on polyvinyl chloride (PVC) and styrene co-maleic anhydride (SMA) blend. Modification of Egyptian bentonite (EB)is carried out using organo-modifier namely; octadecylamine (ODA). Octadecylamine bentonite (ODA-B) is characterized using FTIR, XRD and TEM. Nanocomposites of PVC/SMA/ODA-B are prepared by solution intercalation polymerization from 0.50 up to 5 phr. The nanocomposites are characterized by XRDand TEM. Thermalbehavior of the nanocomposites is studied.The effect of different content of ODA-B on the nano-mechanical properties is investigated by a nanoindentation test method.Also the swelling and electrical properties of the nanocomposites are measured. The morphology of the nanocomposites shows that ODA-B achieved good dispersion in the PVC/SMA matrix. The thermal stability of the nanocomposites is enhanced due to the presence of the ODA-B. Incorporation of 0.5, 1, 3 and 5 phr.ODA-B into the PVC/SMA blends results in an improvement in nano-hardness of 16%, 76%, 92%, and 68% respectively. The elastic modulus increased by 37% from 4.59 GPa for unreinforced PVC/SMA blend to 6.30 GPa for 3 phr. The cross-link density and the electrical conductivity of the nanocomposites areincreasedwith increasing the content of ODA-B. Keywords:PVC, SMA, nanocomposites, nano-bentonite, nanoindentation, crosslink density. I. Introduction Nanocomposites are considered as the next industrial revolution materials. What differentiates nanocomposite materials from classical composites is the degree of control in fabrication, processing and performance that can be achieved nearly down to the atomic scale. In the present age, the main focus area is in identifying a nanocomposite material which is lighter in weight, eco-friendly, bio-degradable, cost-effective, performance-oriented as well as suited for diverse applications. One way of achieving some of the above functionalities is by using organic and natural materials as filler material in different polymer blends. [1] Polyvinyl chloride (PVC), as an important commercial polymer, has been studied and used widely in industrial fields for many years. Polyvinyl chloride exists as two distinctly different thermoplastics, rigid PVC and flexible PVC, which are used in a wide variety of applications. [2] However, due to its inherent disadvantages, such as low thermal stability and brittleness, PVC and its composites are subject to some limitations in certain applications. [3] Therefore, it is necessary to develop new PVC products with altered properties in order to broaden PVC applications, and this achieved by blending it with polymer to enhance its shortcoming. [4] Polymer blends represent an important class of materials in engineering applications. The incorporation of clay nano-filler may provide new opportunities for this type of materials to enhance their applications. SMA polymers with a high molecular weight are widely used in engineering plastic applications, normally in the impact modified and optional glass fiber filled variants. Alternatively, SMA is applied using its transparency in combination with other transparent materials like PMMA or the heat resistance to heat-boost other polymer materials like ABS or PVC. [5] Clay/ polymer nanocomposite materials have attracted great interest because nanoclays can reinforce almost all types of polymer matrices with similar properties than traditional composites, but less weight and better processability. [6] Various studies were conducted on PVC/clay nanocomposites under different curing conditions. The exfoliated clay structure possesses superior properties and gives a few advantages over other nano-fillers like in terms low cost and environmental friendly matters. [1] Nanoindentation is a promising way of measuring the mechanical properties of materials at smaller length and load scales than allowed by other testing methods, thus allowing individual constituents to be examined. [5] Nano and micromechanical testing involves the use of rigid indenters, typically with diamond or diamond-coated tips. [6] Nanoindentation is also known as depth sensing indentation and involves obtaining