Methods for identifying commonly used plastic packaging products
- time:
- 2019-05-13
Daily packaging plastics are generally without additives, such as polyethylene and polypropylene. Food bags, oil drums, fast food boxes and other packaging products made of these plastic materials are non-toxic. How to identify the toxicity of common plastic products? There are many methods of identification, such as appearance method, specific gravity method, boiling water method, combustion method, etc. The more convenient and accurate method is "combustion method". The following is a brief introduction:
The sample of plastic bag is cut off, clamped with tweezers, and burned on the ignited alcohol lamp. Then the difficulty of combustion, the situation after fire, the flame and smoke, the phenomena during combustion and the odor emitted are observed. Finally, a comprehensive judgment is made to know what kind of plastic is. Specific criteria are:
1. Polypropylene plastics: flammable, off-fire follow-up combustion, flame and smoke are orange-yellow, when burning, there are continuous drops of solute, there is the smell of petroleum gas.
2. Polyethylene plastics: flammable, off-fire follow-up burning, flame and smoke blue top yellow, when burning, there are continuous drops of molten matter, emitting the odor of paraffin.
3. Polyvinyl chloride plastics: non-flammable, extinguish immediately after fire. Flames and smoke are green at the bottom and yellow at the tip. After fire extinguishing, there is a stimulating smell of hydrochloric acid.
