SHARING MY BLOG

Have been brave today and posted the link to my blog on one of the linkedin writers group sites -Definitive Serious Writers Group - and have asked if anyone knows how many chapters one should post on a blog before you run into problems with your work being 'published' previously?  Does this count if it is only published on your blog or if you only share three chapters (which is the norm for sending to publishers with a synopsis) does it avoid this trap?  I want to be sure I am not 'shooting myself in the foot' in the long run by posting chapters of my so far unpublished work.