STYRENE-DIVINYLBENZENE COPOLYMERS FUNCTIONALIZED WITH AMINOACID GROUPS: SYNTHESIS, PHYSICOCHEMICAL CHARACTERIZATION

Styrene-divinylbenzene resins are synthetic copolymers known for their chemical resistance, mechanical durability, and good porosity . Amino acids contain functional groups such as amines (-NH₂), carboxylic acids (-COOH). Many of them are natural and non-toxic, making them ideal for applications in biomedical devices, drug delivery, and tissue engineering. This work investigates the physicochemical characterization of two copolymer supports, (containing 6.7% and 15% DVB), functionalized with aminoacid. The syntheses to obtain AP1 and AP2 were performed as presented in a previous paper. FTIR analysis shows shifts in C=O, C–N, and C–H bands at 1510–1365 cm⁻¹ and broad OH/NH absorption at 3510 cm⁻¹, confirming the copolymer's functionalization. EDX analysis of AP1 and AP2 confirmed the presence of nitrogen, with concentrations ranging from 0.4% to 0.5%. TGA was further employed to investigate the impact of grafted aminoacid groups on the thermal stability and decomposition behavior of the copolymers. Thermal stability, as indicated by residual mass at 900 °C, follows the trend:S-6.7%DVBCH₂Cl > AP2 (21.72%) > S-15%DVBCH₂Cl > AP1 (15.52%). AP1 exhibits a greater mass loss (84.48%) compared to S-15%DVB (80.82%), indicating a more significant degradation of its polymer structure. AP2 shows a slightly lower weight loss (78.28%), suggesting improved thermal stability, likely due to structural modifications involving aminoacid functional groups. The differences in functionalization and degree of crosslinking between AP1 and AP2 contribute to AP2’s more thermal stability.