Recently, the glass crucible sealing instrument independently developed by Suzhou Huache Safety Technology Co., Ltd. was officially launched. It can be used as a containing carrier for DSC measurement of chemicals (and can replace existing metal crucibles). The glass crucible sealing instrument can seal glass capillaries containing samples, ensuring the safety and effectiveness of the samples. It reduces safety risks such as sample volatilization and leakage, and ensures the accuracy and success rate of tests. In addition, replacing the metal crucibles conventionally used in DSC with glass capillaries sealed by the glass crucible sealing instrument can significantly reduce testing costs.

I. Research Background

According to GB/T 42300-2022, the reaction safety risk assessment of fine chemical processes shall conduct thermal stability tests on raw materials, catalysts, intermediate products, final products, by-products, wastes, and materials involved in distillation and fractionation processes. The primary instrument for thermal stability testing is the differential scanning calorimeter (DSC). However, erroneous test data obtained using the currently commonly used crucible-based DSC testing methods are not uncommon.Based on the glass capillary crucible method that has been used by Dow Chemical since 1988, Suzhou Huache Safety Technology Co., Ltd. has developed a hydrogen-oxygen flame sealing method for glass capillary crucibles. This glass capillary crucible can replace metal crucibles, addressing issues such as easy leakage, poor pressure resistance, large headspace, susceptibility to sample oxidation, easy vaporization of solvents, unstable baselines, and inaccurate test results for high-energy chemicals associated with metal crucibles. In addition, the use of glass capillary crucibles can significantly reduce the cost of DSC crucible consumables (by as much as ~99%).

II. Product Advantages

For DSC testing, the sample size is small and the contact surface between the test sample and the sample container is relatively high, so the correct selection of the sample container is crucial for data quality. The ideal characteristics of a good DSC sample container are:

(1)    Ability to withstand the pressure accumulated by the sample.

(2)    Chemical inertness in the required test.

(3)    Simple operation.

(4)    Ability to provide a stable baseline.

(5)    Fast thermal response.

(6)    Minimum headspace volume to reduce evaporation endothermic events.

(7)    Allowing the atmosphere in the sample container to be changed by a simple method.