Liquid bitumen, also known as petroleum bitumen, is a complex mixture of dark brown colors consisting mainly of polycyclic hydrocarbons, aromatics, and aliphatic compounds. It has a liquid appearance and a strong pungent odor. Liquid bitumen plays an important role in many industrial and commercial applications. 
The liquid nature of liquid bitumen is due to the presence of a large number of cyclic hydrocarbons in its molecular structure. These compounds can be dissolved in petroleum at high temperatures to form liquid bitumen. When the temperature drops, these cyclic hydrocarbons precipitate out of the petroleum to form solid bitumen. Thus, liquid bitumen is liquid at room temperature but can be transformed into a solid state at high temperatures. 
In addition to being a form of petroleum product, liquid bitumen also plays an important role in many industrial and commercial applications. For example, it can be used as a building waterproofing material, road paving material, anti-corrosion coating, etc. In addition, liquid bitumen can also be used to make polymer materials such as rubber, plastics, and fibers.
When using liquid asphalt, you need to pay attention to safety. Due to the strong pungent odor of liquid asphalt, long-term exposure may cause damage to a person's respiratory system and**. Therefore, when working with liquid bitumen, it is necessary to take appropriate protective measures, such as wearing masks and gloves. 
In conclusion, liquid bitumen is an important petroleum product that plays an important role in many industrial and commercial applications. When working with liquid asphalt, you need to pay attention to safety and take appropriate protective measures. 