I've been researching this a bit and there are various ways. The simplest seems to be a 50-50 mix of PVA or wood glue and water. Alternatively, you can buy specialist sealers (but they're probably quite expensive) and car primer is meant to work well too.
To use as a door, chess board or anything else.
Yes.
mdf is strong but not very strong
Yes. MDF contains formaldehyde, and so it cannot be burned - it releases very toxic gases. Respiratory protection should be worn while sanding it. There are companies that make non-toxic MDF, but they are rare. Most all MDF you encounter will be toxic if not covered by a sealer/paint/etc.
yes it is.
Can students use mdf board for tech studies in schools in south australia? It is a yes or no answer.
MDF plywood
To use as a door, chess board or anything else.
Yes.
MDF= Medium Density Fiberboard
mdf is strong but not very strong
mdf is a manufactured wood material
How can you use medicines safely
1.60mm is the thinnest mdf we make
no, MDF cannot observe water
The difference is that MDF is MDF and Pine is Pine, two different names, Genius.
MDF is compressed wood fibres held together with resin.