| Abstract: | A reactive extrusion process was developed to toughen an amorphous copolyester (PETG) of ethylene glycol, terephthalic acid and 1,4‐cyclohexanedimethanol using either a maleic anhydride grafted polyethylene–octene elastomer (POEg), or a maleic anhydride grafted mixture (TPEg) of the polyethylene–octene elastomer and a semicrystalline polyolefin plastic as the impact modifier. TPEg showed an important toughening effect on the PETG. A sharp ductile‐brittle transition was observed when the TPEg content was about 10 wt %. For POEg toughened PETG, the ductile–brittle transition required a higher content in POEg, ∼15 wt %. Evolution of the topography and morphology of the blends and the relationship between impact strength and topography were discussed. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 2801–2809, 2000 |
