Preparation and thermal performance of nitrocellulose coated by polydopamine

Abstract

The existing stabilizers for nitrocellulose (NC) have various disadvantages of harming human health and polluting the environment, which does not meet the requirements of “green” propellants. This research work investigates the self‐polymerization of dopamine to prepare polydopamine (PDA) coated NC composites, and explores the effects of PDA on the thermal stability of NC. SEM, FT‐IR, and RAMAN were applied to investigate the changes of NC surface morphology and chemical structure. The results show that PDA is effectively coated on the NC surface and form a dense PDA film. The thermal decomposition behavior of NC was studied by TG and DSC, and the thermal decomposition activation energy was calculated. The results showed that the thermal stability of the physical mixture did not improve. The thermal stability of the complex increases first and then decreases with increasing of the concentration of dopamine hydrochloride. The optimal reaction conditions are that the concentration of dopamine hydrochloride is 3 g/L and the reaction time is 24 h. The thermal decomposition activation energy of the sample under the optimal conditions is 190.00 kJ/mol, 8.91% higher than that of NC (174.45 kJ/mol), which proves that PDA has the ability to improve the thermal stability of NC.

Study of the preparation and properties of polyvinyl chloride/nitrocellulose polymer blends

“…Comparing Figs 6(a) and 6(b), it can be seen that the pore size of PVC/NC is substantially smaller at higher loadings of NC. The semicrystalline phase of NC was found to be partially present in PVC 42 . Figure 7 shows the decreased trend of pore size from lower to higher loading of NC.…”

“…In particular, the IR spectrum of NC contains all the nitro group peaks. 42 The absorption band at 2955 cm −1 is attributed to the C-H stretching vibration. The band at 3334 cm −1 is attributed to the O-H stretching vibration of the free hydroxyl group present in NC.…”

“…The peaks present at 835 and 741 cm −1 are attributed to O–NO 2 stretching and O–NO 2 asymmetric bending, and the band at 670 cm −1 is assigned to O–NO 2 symmetric bending. In particular, the IR spectrum of NC contains all the nitro group peaks 42 . The absorption band at 2955 cm −1 is attributed to the C–H stretching vibration.…”

“…The semicrystalline phase of NC was found to be partially present in PVC. 42 Figure 7 shows the decreased trend of pore size from lower to higher loading of NC. The diameter of the pores was approximately 17.43 μm.…”

Surface modification of cellulose nanofibers by oxidative polymerization of tannic acid/ethanediamine and their polyvinylalcohol composites

“…[17][18][19][20] For this purpose, polydopamine has also been employed for surface modification of cellulose nanomaterials for composites. [21][22][23] However, the limited precursors and high cost have impeded the practical applications of polydopamine. Recently, phenolic compounds derived from plants have emerged as alternatives of dopamine for development of functional coatings or nanomaterials.…”