热固性树脂固化过程热膨胀与收缩系数测量装置

It is difficult for conventional instrument to measure the thermal expansion coefficient and shrinkage rate of thermosetting resin because of the strong coupling among cure degree, thermal expansion and chemical shrinkage volume during cure process. To solve this problem, a measuring device is designed with reference to the PVT-α method. The reaction heat and cure temperature are obtained through the heat flow sensor and thermocouple of the device. Then, the cure degree of thermosetting resin sample can be determined by the integral of reaction heat. The volume change of thermosetting resin sample is determined by the displacement sensor. Combining the volume change with the evolution of cure degree, the thermal expansion and cure shrinkage volume during cure process are decoupled to obtain the thermal expansion coefficient and the shrinkage rate at the same time. By using this device, the thermal expansion coefficient of silicone rubber material is measured. Compared with the standard value, the error is 4.93%, which verifies the feasibility of the device. The thermal expansion coefficient of thermosetting resin (epoxy resin E-51) during cure is measured, which decreases with the cure degree linearly, with the expression: CTE_cross(α)=8.265 1×10^-4(1-α)+7.566 4×10^-4α (1/℃), and the shrinkage rate is determined at the same time, with the value of 1.87%. The developed device in this article provides a method for measuring the thermal expansion coefficient and shrinkage rate of thermosetting resin during cure.