调制示差扫描量热法测定ABS树脂玻璃化转变温度

Measurement of Glass Transition Temperature of ABS Resin by Modulated Differential Scanning Calorimetry

采用调制示差扫描量热法测定了ABS树脂(丙烯腈-丁二烯-苯乙烯树脂)及其共混物基体树脂相的玻璃化转变温度(T_g),并研究了ABS树脂的升温过程与基础升温速率(β)、调制振幅(A_T)的相关性。实验结果表明,ABS2树脂及其共混物的总热流和可逆热流部分在100℃左右均有两个T_g,这可能是由于丙烯腈与苯乙烯相共混时相对分子质量有差异造成的,在不可逆热流曲线上也均有两个基本对应的吸热峰,且低温吸热峰的焓值较大;随β的增大,ABS1树脂的总热流和可逆热流部分的T_g基本呈升高趋势,不可逆热流部分的吸热峰的焓值逐渐减小;随A_T的增大,ABS1树脂总热流部分的T_g基本不变,但可逆热流部分的T_g降低,不可逆热流部分的吸热峰的焓值增大。

Glass transition temperatures of matrix phases of ABS （acrylonitrile-butadiene-styrene） resins and their blends were characterized by means of modulated differential scanning calorimetry （MDSC）. Dependences of glass transition temperature（Tg） of ABS resin on underlying heating rate （β） and modulated amplitude （Aγ） in heating process were studied by MDSC. Total heat flow and reversing heat flow of ABS2 resin and its blend showed two Tg near 100℃, which could occur due to difference in relative molecular mass when acrylonitrile was blended with styrene. There were also two corresponding endothermic peaks on non-reversing heat flow curve and enthalpy of low-temperature endothermic peak was larger. When β increased, Tg of ABS1 resin in the total and reversing heat flow basically increased, but the enthalpy decreased gradually in non-reversing heat flow. With increasing of AT, Tg of ABS1 resin in the total heat flow basically kept unchanged, but Tg in reversing heat flow gradually lowered and enthalpy rose in non-reversing heat flow.