Can research rejected by journals has any chances being accepted if it is disseminated by the social media?
In my experience, even peer-reviewed publications are rarely read. There are a handful of influential papers in each field (from what I have seen) which are read and cited. But beyond these, a lot of work is only cited to keep people happy.

Therefore, I think that the chances of people reading the work without it being peer-reviewed are very slim.

If you want your work to get reviewed and it is being rejected before being read (this is what you're saying, I think), then you perhaps need co-authors that know the field better.