Solid phase synthesis of aromatic isophthalic oligoamides with controlled molecular weight

The synthesis of oligo(hexafluoroisopropylidene isophthalamide) on a solid support of SynPhase™ Lanters is described. The repetitive coupling steps using symmetrical diamines and diacid chlorides allows to obtain aromatic oligoamides with controlled molecular weight (image = 5480 g/mol) and narrow molecular weight distribution (PDI = 1.03) as evidenced by gel permeation chromatography. Moreover, the FTIR and 1H NMR analysis demonstrated their chemical nature and OH-end groups functionality. The thermal properties of aromatic oligoamides were found to be lower, as expected, than those of poly(hexafluoro-isopropylidene isophthalamide), the same repeating unit high molecular weight polyamide, as judged by differential scanning calorimetry and thermogravimetrical analysis.