Preparation of wood with thermoplastic properties Part 1. Classical synthesis

Aspen wood (Populus tremula) as sawdust was chemically modified through a t wo-step procedure: esterification with maleic anhydride and subsequent olig oesterification with glycidyl methacrylate and maleic anhydride. Chemical a nalyses and infra-red spectroscopy revealed the differences in the chemical composition and structure of wood as a result of this treatment. These cha nges were also reflected by a hygroscopicity test and thermal analyses such as thermogravimetry and thermomechanical analysis. The esterified wood sho wed an increased hygroscopicity and a decreased thermal stability compared to unmodified wood. In contrast, the oligoesterified wood demonstrated a re duced hygroscopicity and a comparable thermal stability up to about 200 deg rees C. The thermomechanical analysis of oligoesterified wood clearly showe d a significant softening phenomenon in the range 80-140 degrees C, a direc t evidence of the thermoplastic properties gained by this chemical modifica tion.