Chemistry of chocolate seizing by heat

I can understand why chocolate seizes when it gets wet. -Chocolate is very dry and any available water is bound up by the sugar or lecithin. The fat coated particles glide past each other nicely. Add a little bit of water and the particles stick together.

What I don't understand and haven't been able to find yet is what happens when chocolate gets too hot. - Experience tells me it burns easily as well as gets very lumpy. However, I don't understand the chemistry of it. Is it the cocoa butter or cocoa solids that are burning? Perhaps it's the milk or sugar burning?

Can cocoa butter take high heat? I've read on here about adding cocoa butter to caramel at the end of cooking the caramel. Can cocoa butter take 230+ temp (i'm in the mountains so we don't cook our caramel as hot.) I've been concerned it will burn and taste bad.

We made a batch of caramel with cocoa butter (adding it at 160 & 140 degrees Fahrenheit) but stirring at those lower temps caused the caramel to crystallize.

Does anyone have an article on cocoa butter or chocolateseizing from heat?

Thanks,

Larry