chemical modification
Process by which at least one feature of the chemical constitution of a polymer is changed by chemical reaction(s).
A configurational change (e.g., cis@C01092@@I03295@) is not usually referred to as a chemical modification.
PAC, 2004, 76, 889. 'Definitions of terms relating to reactions of polymers and to functional polymeric materials (IUPAC Recommendations 2003)' on page 891 (