Thermal Decomposition of Nitrile Gloves by Sample Observation STA-MS

Introduction

Nitrile gloves are widely used as disposable gloves for medical, nursing care, food processing, and others. It is used as an alternative to natural rubber gloves against latex allergies. Recently, the demand for nitrile gloves has rapidly increased, as it is used not only in medical and food-related fields but also in food and food outlets, retail stores and homes as a means of preventing infection. It is well known for its excellent strength, elasticity and chemical resistance, as well as resistant to piercing and pulling. In this application, we analyze the evolved gases from nitrile gloves.

Measurement and results

A size that fits the sample pan was cut out from the nitrile glove and was used in this experiment. Using the sample observation STA-GC/MS, it was heated from RT~600℃ at 20℃/min in He atmosphere. Figure 1 shows the STA results and sample observation images revealing discoloration and shrinkage that can be observed after 300℃, and foaming is visually evident from 450℃ due to decomposition.  

Figure 2 shows the TG curve and the MS ion thermograms of main detected gases (m/z). The mass loss on the TG curve at 200℃ is 3%, while an 86% mass loss is seen from 300~500℃.  

The MS results revealed that the gas evolved from the hydrocarbon chain was detected at 200℃ . This could be an additive derived from the softener. In addition, it was confirmed that a large amount gas derived from nitrile rubber decomposition was evolved during the main decomposition at 300~500℃.  

Figure 1: STA results and sample observation images revealing discoloration and shrinkage

Figure 2: TG and MS ion thermograms 

Figure 3: Mass spectrum at 182℃

Figure 4:  Mass spectrum at 460℃