Polypropylene is a microwave safe plastic. I used to have some bowls like this:
https://www.amazon.com/dp/B015G63DYM/ref=cm_sw_r_cp_apa_glt_fabc_GPH60BKBQEE1MQR3CSMV
I put hot liquids in them but never used them in the microwave because I have glass mixing bowls for that.
Tupperware has a wide range of microwave safe bowls. Maybe something like this would be useful:
https://my.tupperware.com/YUSUFABULOUZ/ProductDetails?ID=10137313000_FRPUS1230