The problem is residual gunk ( aka paint pigment particles ) which gets into the base of the bristles and forces them apart. Hard to prevent even with very thorough cleaning.

A clean with a strong solvent before wrapping or tying the bristles to shape will help to prolong life, however I generally treat brushes as a consumable item which will eventually pass their use-by date. The initial cost of the brush is often the critical factor here.

On non-critical jobs I often use el-cheapo brushes and discard after one use – the cost of the solvent to clean them properly often exceeding the cost of the brush ( unless of course you are using water-based paints ).

Incidentally for brush washing I use the three jar system. First jar for the initial clean, then into the second and finally the third for the final wash. When the solvent in the first jar becomes too dirty it is discarded and the jar washed. Jar 2 then is promoted to jar 1 and jar 3 to jar 2. The newly clean jar is filled with clean solvent and becomes jar 3. This hopefully results in minimal particulate matter being present in the final wash.

Pero

My wife says “get some new ones and look after them better. Buy the right ones for the job. Not be so ‘heavy handed’ when using them”. Those were only suggestions as to the problem as user details were not forthcoming.

Both she, and her late mother, are/were artists for many a year. Her mother was a particularly good one. My wife suggests getting care advice from the art shop when new brushes are acquired.

Try soaking them in distilled white vinegar for a couple of hours. Then manually 'point' them with your fingers and let them dry. No guarantee, but sometimes works for me. Mike

This video by Windsor & Newton on brush cleaning may be informative.

And be thankful it's not one of these brushes

Rob

This is rather like the recent 'how to make toast' cooking program. Like someone over five years old need to be told that it is better to clean it after use.

If it has been used with acrylic find a scrap of whatever that has been used with that paint and well dried. Try your solvent on that because if it has no effect it isn't going to cean your brush post drying. If you find a functioning solvent beware that it doesn't destroy the glue holding the bristles together inside the ferule.
If the paint is dried to a brittle rather than piable plastic state it can help to roll the fibres to crush and break the material build up.

I agree with the above, always clean brushes thoroughly, and don't expect them to last forever (though you can of course demote them to less exacting duties). For both artistic and other purposes, the synthetic ones are excellent now, and cheaper than sable or whatever.

I'm just posting really, to add that acrylic usually succumbs to meths -you could probably also use IPA (no, not the beer, you drink that whilst the brush is soaking).