Is the soundproof felt made of rubber?
Relatively speaking, the environmental protection of soundproof blanket with PVC as raw material is good, but unfortunately, now most sold on the market are made with repeated recycling of PVC waste insulation mat, the soundproof felt added a large number of chemical additives, many chemical additives are harmful to the human body.
Now most of the soundproof felt is made of PVC, and PVC is the PVC. Your decorator doesn't understand it. It must be a soundproof felt as a rubber sheet. The rubber board must not be used as a deadening felt, because it has an unpleasant odor and is not environmentally friendly.
Early sound deadening felt was made of rubber, but that was ten years ago.