Effect of unsaturation on physicochemical properties of maleic anhydride–grafted acrylonitrile butadiene styrene terpolymer

In order to find out the shift of ductile nature of acrylonitrile-butadiene-styrene (ABS) polymer to brittle nature while maleic anhydride (MA) grafting, the iodine value of different MA-grafted ABS (MA-g-ABS) sampled has been determined. The iodine value of thermoplastic polymer is found by Wijs method with slight modification to overcome the poor solubility of thermoplastics in tetrachloromethane. Different samples with varying MA content were prepared using internal mixer. All the specimens were characterized by attenuated total reflectance IR spectroscopy and X-ray diffraction analysis. The iodine value measurements revealed that grafting and cross-linking evidently reduced the unsaturation in ABS polymer matrix. The grafting of MA causes the decrease in impact strength, flexural modulus, and a significant increase in crystallinity, tensile strength, yield point, and flexural strength, whereas thermal stability remains intact. Field emission scanning electron microscope images showed noticeable difference in broken surface texture between ABS and grafted samples