Transit in Shanghai (Thai passport)

I plan to fly back from the US to Bangkok, Thailand.

I have 2 tickets by 2 airlines.
- fly from chicago (USA) to shanghai (china) , 3 hours later , fly from shanghai (china) to Bangkok (thailand).

Do i need Chinese Visa? Since i have to pass immigration , get my luggage and check in again for my flight shanghai to Bangkok .

Remark: I will stay in airport because i have only 3 hours, definitely cannot go out due to time constraint.

I dont think i have to do entry permit ( am i correct ?)