Branching in Poly(Furfuryl Alcohol) Oligomers: A HNMR Spectroscopy Study

Branching is one of the complexities arising, in different extents, during polymerization reactions. Here, an average degree of branching is determined for poly(furfuryl alcohol) (PFA) oligomers by processing of HNMR spectroscopy data in conjunction of gel permeation chromatography (GPC) findings and especially considering the resin chemical structure. PFA resin was polymerized by cationic polymerization of furfuryl alcohol (FA), purified and then thoroughly characterized by gel permeation chromatography and NMR spectroscopy. A theoretical model was developed for the changes occurring in chemical shifts of methylol and methylene ether groups of PFA resin as a function of degree of branching at a definite DPn. Based on the calculations, an average degree of branching was determined for the oligomers