Novel synthetic route of a trehalose-based linear polymer by ring opening of two epoxy groups with aliphatic diamine

A diepoxide compound derived from trehalose, 2,3-anhyrdo-4,6-O-benzylidene-α-d-allopyranosyl 2,3-anhydro-4,6-O-benzylidene-α-d-allopyranoside, was synthesized and reacted with aliphatic diamines. The ring-opening reaction was carried out in 1-methyl-2-pyrrolidone (NMP) in the presence of triphenylphosphine (TPP), tris(4-methoxyphenyl)phosphine (TMPP) or 2-ehtyl-4-methylimidazole (2E4MIm), as a base catalyst. The reaction of the diepoxide compound with 1,6-diaminohexane yielded a soluble polymer with weight average molecular weight (Mw)∼6300 (GPC) and did not yield insoluble matter. The reaction of the diepoxide compound with N,N′-dimethyl-1,6-diaminohexane yielded a polymer with Mw∼6500 (GPC). The product was soluble in many organic solvents such as NMP, N,N-dimethylformamide (DMF), tetrahydrofuran (THF), acetone, toluene and ethyl acetate. Thermal analysis with differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) revealed that the glass transition temperature of the polymer was ∼100 °C and that the degradation temperature was ∼320 °C.