Thermo-analytical study on transitions in styrene–maleic anhydride copolymers with low- and high-molecular weights

摘要: Abstract The thermal behaviour near the glass transition temperature Tg was studied for poly(styrene-co-maleic anhydride) or (SMA) copolymers with a broad range of molecular weight (Mw = 5500–180,000 g/mol) and amount maleic anhydride (22–50 mol%). influences structure low- high-molecular were detailed by using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) modulated (TMDSC). Data from TGA provide evidence variations in stability, mainly over first degradation step up to 350 °C. Most interesting data results TMDSC SMA, where reversible heat flow Δcp remains almost constant, while non-reversible gradually increases MA. Comparing linear model cannot be applied global anhydride, it can successfully implemented if more two constituents is considered. As such, further provided intrinsic heterogeneous SMA “styrene-rich” “maleic-anhydride-rich” polymer segments.