Preparation and Characterization of Cyclodextrin Coated Red Phosphorus Double-Shell Microcapsules and Its Application in Flame Retardant Polyamide6

Shangkai Lu; Junbang Liu; Lijuan Zeng; Lianghui Ai; Ping Liu

doi:10.3390/polym14194101

Preparation and Characterization of Cyclodextrin Coated Red Phosphorus Double-Shell Microcapsules and Its Application in Flame Retardant Polyamide6

Polymers (Basel). 2022 Sep 30;14(19):4101. doi: 10.3390/polym14194101.

Authors

Shangkai Lu¹, Junbang Liu¹, Lijuan Zeng¹, Lianghui Ai¹, Ping Liu¹

Affiliation

¹ State Key Laboratory of Luminescent Materials and Devices, Research Institute of Materials Science, South China University of Technology, Guangzhou 510640, China.

Abstract

Using the melamine borate and crosslinked β-cyclodextrin as shell materials, the double-shell microcapsules (Mic-DP) of red phosphorus (RP) was prepared, and its flame-retardant effect on polyamide 6 (PA6) was investigated. Compared with RP, Mic-DP showed lower hygroscopic and better inoxidizability. The limiting oxygen index (LOI) of PA6/13%Mic-DP was 27.8%, and PA6/13%Mic-DP reached V-0 rating. After the addition of 13% Mic-DP, the total exothermic (THR), peak exothermic (PK-HRR), and average effective thermal combustion (AV-EHC) rates of PA6 decreased. In addition, in order to investigate its flame-retardant mechanism, the pyrolysis gas chromatography-mass spectrometry (Py-GC-MS), scanning electron microscopy (SEM), and Fourier transform infrared (FT-IR) methods were used, and the results showed that mic DP acted as a flame retardant in the gas and condensed phases. The Mic-DP exhibited good compatibility and dispersibility in PA6.

Keywords: cyclodextrin; flame retardant; melamine borate; microcapsules; red phosphorus.

Grants and funding

This research was financially supported by the Natural Science Foundation of Guangdong (grant No. 2016A010103003) and Natural Science Foundation of Guangzhou (grant No. 201604010034).