Company may be first to experiment with unstable polymer (8)
I believe the answer is:
employer
'company' is the definition.
(thesaurus)
'first to experiment with unstable polymer' is the wordplay.
'first to' indicates taking the first letters.
'with' means one lot of letters go next to another.
'unstable' indicates an anagram.
The initial letter of 'experiment' is 'e'.
'polymer' is an anagram of 'mployer'.
'e'+'mployer'='EMPLOYER'
'may be' acts as a link.
(Other definitions for employer that I've seen before include "One paying staff" , "Boss or proprietor" , "One who engages workers" , "One who uses" , "One's worked for" .)