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Effect of Biaxial Stretching on Mechanical Properties and Surface Roughness of PMMA Films

Abstract Recently the use of PMMA films as the top layer of dish membrane solar collectors has gathered popularity. The mechanical properties and surface smoothness of PMMA films are the important factors affecting the durability and optical performance of these stretched membrane solar collectors. In this paper, we present the results of our experimental study on the effect of biaxial stretching on mechanical properties and surface roughness of PMMA films. Biaxial stretching was found to improve both the mechanical properties and surface smoothness of PMMA films.