The subject mater of "Hate" is hate, in a general a specific sense. You use the repetition of hate effectively to carry both the subject and the corrosive nature of hate. Generally, as I see it, you purpose is to express what it is about hate that is destructive.
You use repetition effectively, repeating Hate as a refrain between each couplet. Structurally, the combining of a Couplet and a single word refrain worked well.
In my opinion, this poem work better if you used condensed language. Condensed language in poetry eliminate unnecessary or extraneous words. (
Condensed Poetry Writing Exercises)
For instance, the First line of the last couplet could be condensed to "Ugly word full of vile, negative contagions." would be condensed, shortening the line and using words with more impact. You might also consider using other poetic devices like Alliteration or Consonance.
One other thing, you endstop most of the lines with periods. This gives it a choppy feeling, rather than a smooth flow of words. Consider enjambment, leaving punctuation off of the ends of some of the lines in your couplets.
Good luck with this poem.