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The two-dimensional energetic polymer triaminoguanidine–glyoxal (TAGP) has been used in modification of EMs to formation of various hybrid materials for higher density and better stability due to its excellent capability to desensitize high energetic crystals without any energy loss. In this paper, theoretical calculations based on ReaxFF-MD were performed to demonstrate the thermal decomposition mechanisms of TAGP, which has been further proved by experimental results from Pyro-GC/MS analysis. The results show that there are three dominant pathways for the initial decomposition of TAGP, i.e. , the breakage of C-N bond with production of C 2 H 3 ON 2 (most likely to happen), the scission of N-N bond with release of C 2 H 2 ON, and the rupture of N-N bond accompanied with the proton transfer to release C 2 H 3 ON. Therefore, the C 2 H 3 ON 2 , C 2 H 2 ON and C 2 H 3 ON are the dominant initial decomposition products of TAGP, which may gradually transform to the final gaseous products. The experimental results confirmed the presences of these substances. The major final gaseous products of TAGP include N 2 , H 2 , H 2 O, NH 3 , NH 4 , NH 2 , N 2 H, N 2 H 2 , HCN and CO 2 , among which the concentration of N 2 is the highest, relatively higher than H 2 , H 2 O and NH 3. Besides, the initial decomposition rate of TAGP largely depends on its MW. The activation energies for formation of C 2 H 3 ON 2 and N 2 under isothermal conditions has been obtained to further illustrate the effect of MW on the decomposition rate. • Three types of typical TAGP structural models have been constructed according to the measured molecular weights. • The detailed decomposition mechanisms of TAGP have been proposed. • Their final thermolysis products have been mutually confirmed by ReaxFF-MD simulations and Pyro-GC/MS experiments. [ABSTRACT FROM AUTHOR]

• A homogenous polysaccharide SPS60 was isolated from Sabia parviflora. • The monosaccharide component of SPS60 was glucose. • SPS60 showed significant hepatoprotective activity. • The AFM images showed SPS60 was a massive sphere with a diameter of 21 nm. The extraction, purification, structure and hepatoprotective activity of a homogenous polysaccharide (SPS60) from Sabia parviflora were investigated. SPS60 was screened after purification with Sephadex G-100 and showed the excellent hepatoprotective activity. Its structural characteristics were investigated by Time of flight mass spectrometry (TOF-MS), PMP Pre-column derivatization-HPLC (PMP-HPLC), nuclear magnetic resonance (NMR) spectroscopy and Atomic Force Microscopy (AFM). The results showed that SPS60 possessed the molecular weight of 16900 Da and the monosaccharide component was glucose, as well as a 1 → 6 glycosidic bond. The results of atomic force microscopy (AFM) show that SPS60 is a blocky sphere in solution. Furthermore, the SPS60 could significantly improve the survival rate of LO2 hepatocytes which were damaged by CCl 4. Therefore, SPS60 may be an active substance of S. parviflora as a local functional tea. [ABSTRACT FROM AUTHOR]