This document is the Accepted Manuscript version of a Published Work that appeared in final form in Industrial and Engineering Chemistry Research , copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see Published Work, see http://pubs.acs.org/doi/abs/10.1021%2Fie303130e ; The formation of smectic phases in side-chain liquid crystal copolymers, SCLCPs, containing sulfonic acid-based nonmesogenic units, has been investigated using variable temperature FT-IR microscopy. Two copolymers have been characterized, namely, the poly[10-(4-methoxy-4′-oxy-azobenzene) decyl methacrylate]−copoly[2-acrylamido-2-methyl-1- propanesulfonic acid]s, the X-MeOAzB/AMPS copolymers, containing X = 0.71 and 0.56 mol fraction of mesogenic sidechains, respectively. For comparative purposes the corresponding side chain liquid crystal homopolymer, poly[10-(4-methoxy-4′- oxy-azobenzene) decyl methacrylate], MeOAzB, has also been characterized. The 0.56-MeOAzB/AMPS copolymer exhibits a bilayer smectic A phase, in which the mesogenic side chains constitute one layer with a SmA1 packing arrangement and the sulfonic acid groups another; whereas in the smectic A phase shown by the 0.71-MeOAzB/AMPS copolymer, the acid groups are located within the smectic layers giving a partially interdigated SmAd phase and reducing side chain packing efficiency. Smectic stabilization is attributed to a combination of stronger interactions involving the ester groups, as reflected in changes to the C O stretching band at ν ∼ 1730 cm−1 , and hydrogen bonding between the amide groups within the acid-based layers, as inferred by changes to the NH stretching band at ν ∼ 3320 cm−1 . The temperature response observed for groups with different chemical environments permits the mapping of the short-range interactions between the various structural components in SCLCPs with a view to controlling the functionality of the materials. ; Spanish Ministry of Science and Innovation ENE2007-67584-C03 ; Spanish Ministry of Science and Innovation UPOVCE-3E-013 ; Spanish Ministry of Science and Innovation IT2009-0074 ; Spanish Ministry of Science and Innovation ENE2011-28735-C02-01 ; FPI predoctoral grant ; FPU predoctoral grant ; Generalitat Valenciana GRISOLIAP/2010/057 ; Generalitat Valenciana GRISOLIAP/2012/056 ; Generalitat Valenciana GRISOLIAP/2013/A/036 ; UPV PAID 05-09-4331 ; UPV PAID-06-11 ; ACOMP/2011/189 ; Martinez-Felipe, A.; Imrie, CT.; Ribes Greus, MD. (2013). Study of Structure Formation in Side-Chain Liquid Crystal Copolymers by Variable Temperature Fourier Transform Infrared Spectroscopy. Industrial and Engineering Chemistry Research. 52(26):8714-8721. doi:10.1021/ie303130e. ; Senia ; 8714 ; 8721 ; 52 ; 26