The rocket will drop something like paper within a few seconds after taking off. What is this? What is the function?

The fragments of the rocket are actually "cotton-padded clothes"

When the Shenzhou VI spacecraft was launched, people found from TV pictures or photographic images that when the rocket lifted the spacecraft away from the launch tower, it kept dropping some debris.

According to space launch experts, the temperature difference between morning and evening in Jiuquan Satellite Launch Center, which is located in the Gobi desert in northwest China, has increased. In order to minimize the adverse effects of low temperature on rocket launch, some thermal insulation measures are often taken during rocket test launch, such as blowing hot air, wearing cold clothes, light bulb irradiation, sticking foam plastics, etc. After the rocket is ignited and lifted off, the intense friction of the atmosphere will peel off these foam plastics from the rocket body and become fragments that people see falling from the rocket body.