Characterization of HTPBs chemical constitutions and molecular weights

5 Characterization of HTPBs chemical constitutions and molecular weights 

There are two aspects in the characterization of polymers and their blends (1) chemical constitution, (2) molecular weight (MW) and its distribution (MWD). Identification of the chemical constitution is conducted by the manufacturer and rarely performed by the industrial or academic users. 

Method Molecular structure interactions Miscibility Surface and interphase Phase separation Crystal structure Orientation 

Notes E = excellent G = good F = fair SALS, small angle light scattering PCM, polarized contrast microscopy TOA, thermal oxidative analysis. Other abbreviations are listed in Section 2.12. 

The exception may be the determination of fine isomeric sequences (e.g., in polyolefins, POX identification of tactic content (for example in PVC), or identification of end groups (e.g., in PA, PEST, or PO). The applied analytic methods include FT-IR, SANS and pulsed nuclear magnetic resonance (NMR). These may be combined with pyrolysis, followed by chromatography and mass spectrometry (MS). For the users of HTP, the most pertinent information is how the polymeric structure, MW and MWD, changes with time. 

---