Preparation of β-Cyclodextrin Inclusion Complex and Its Application as an Intumescent Flame Retardant for Epoxy

Abstract

A new P-N containing the flame retardant, which was namely N,N′-dibutyl-phosphate diamide (DBPDA), was synthesized and it was assembled into the cavity of β-cyclodextrin (β-CD) to form an inclusion complex (IC). The structure and properties of IC were characterized by Fourier transform infraredspectroscopy (FTIR), wide-angle X-ray diffraction (WAXD), 1H nuclear magnetic resonance (1H NMR), scanning electron microscopy with X-ray microanalysis (SEM-EDS), differential scanning calorimeter (DSC) and thermal gravimetric analysis (TGA). 1H NMR and SEM-EDS were also used to identify the molar ratio of β-CD/DBPDA in IC and the results from the analyses indicated that their molar ratio was 1:1. In order to test the flame retardant effect of IC, it was added to epoxy (EP). IC was proposed to be able to act as an intumescent flame retardant (IFR) system in EP through a combination of β-CD and DBPDA properties during the combustion process. β-CD is a biomass carbon source, which has the advantages of environmental protection and low cost. Furthermore, DBPDA is both a source of acid and gas. When IC was heated, IC had the advantage of acting as both a carbon source and foam forming agent, while the DBPDA component were able to directly generate phosphoric acid and NH3 in situ. The impact of IC in low additive amounts on flame retardancy of EP was studied by the cone calorimeter test. When only 3 wt % IC was incorporated, the peak values of heat release rate (pHRR) and smoke production rate (pSPR) of EP were reduced by 22.9% and 33.3% respectively, which suggested that IC could suppress the heat and smoke release efficiently.

Cyclodextrins and Cyclodextrin Derivatives as Green Char Promoters in Flame Retardants Formulations for Polymeric Materials. A Review

“…Very recently, Zhao et al synthesized new P-N containing flame retardants molecules [53], N,N′-diamyl-p-phenylphosphonicdiamide (P-MA), and by Shan et al [54], N,N’-dibutyl-phosphate diamide (DBPDA) to be used in FR formulations for epoxy resins (EP).…”

Recovery, reusability and stability studies of beta cyclodextrin used for cholesterol removal from shrimp lipid

“…(2019) prepared b-CD inclusion complex and analyzed for NMR spectra using DMSO as a solvent. 26 The spectra of b-CD before and aer inclusion suggested the chemical shi for H3 (0.011 ppm), H5 (0.006 ppm) and H6 (0.009 ppm), more likely due to the complex formation with b-CD. Inclusion complex between b-CD and phenylphosphonicdiamide showed the shi of H3, H5 and H6 protons around 0.002, 0.002 and 0.001 ppm, respectively.…”

Preparation of novel biomass humate flame retardants and their flame retardancy in epoxy resin

“…As we know that, the biomass-based flame retardant is a new type of environmentally friendly flame-retardant material that is processed from the by-products or waste materials. Most of these biomass-based flame-retardant structures, such as chitosan, [4,5] lignin, [6,7] cyclodextrin [8,9] contain a huge amount of oxygen-containing functional groups and Guangya Liu and Huili Shi contributed equally to this work.…”