色差计测定PTA b值影响因素浅析

Analysis on the influence factors for determination of PTA b value with colour difference meter

探讨了色差计测试精对苯二甲酸(PTA)的b值时,影响b值的相关因素,如制样方法、称样量、测量仪器、不同光源、观测角和孔板尺寸、操作手法、样品温度等。结果表明不同制样方法对b值影响很小,样品杯法比压片法更经济快捷。同型号测量仪器存在明显台差,不同观测角和孔板尺寸对结果影响很大,测试结果应注明条件。

This paper discussed the influencing factors for determination of PTA b value with colour difference me- ter, such as sample preparing method, sample mass, measuring instrument, different light source, observation an- gle and aperture, operating practices, sample temperature and so on. The result shows that different sample prepar- ing methods have little effect on b value. Sample cup method was more economic and time-saving than tablet press. The same type of instruments existed obvious deviation. Different observation angle and aperture greatly affected the measurement results, so the determination conditions should be clear indicated.