Usually, the washing instruction on label will be helpful whether for cleaning silk quilts or polyester comforters. If you can’t find them, you could do as the following tips.
First of all, you could place your polyester duvet in the washing machine and wash them in a gentle setting with soft laundry detergent. After you have washed them, you could place it in the dryer and dry on the warm setting for 30 to 40 minutes. If it is still wet, you could dry it in another five to ten minutes until it is OK.
It will take another 8 hours to make sure that the silk comforter is dry enough for placing on your bed.