ULTRASONIC BEHAVIOUR STUDIES ON METHYL METHACRYLATE COPOLYMERS
甲基丙烯酸甲酯共聚物的超产特性研究

Ultrasonic attenuation and velocities have been measured in three kinds of copolymers: Methyl methacrylate-Butyl methacrylate (MMA-BMA), Methyl methacrylate-Methyl acrylic acid (MMA-MAA) containing different kinds of crosslinkers and Styrene-Methyl acrylic acid (ST-MAA) containing crosslinker EGD and BA respectively.Experimental results indicate that ultraconic attenuation increases and velocity decreases in MMA-BMA as increasing BMA content. Adding crosslinkers EGD or BA in MMA-MAA and in ST-MAA, ultrasonic attenuation inbcreases,velocity decreases evidently. The glass transition temperature Tg in MMA-BMA shifts towards lower temperature as BMA content. increasing.