Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7818786 | Polymer | 2018 | 8 Pages |
Abstract
To improve the flame retardant efficiency of aromatic Schiff base (BA), and adjust the crosslinking temperature of imine groups, a cyano group, an electron-drawing group has been introduced into the chemical structure of aromatic Schiff base to obtain a third monomer for poly(ethylene terephthalate) (PET), named as dimethyl-5-[(2-cyanobenzylidene)amino]-isophthalate (CBAA). Thermogravimetry-differential scanning calorimetry (TG-DSC) and dynamic rheological results prove that the PET-based copolyester containing CBAA (CBAAnPETs) can cross-link at higher temperature than that containing BA, which will not affect the preparing and processing of PET. DSC and wide angle x-ray diffraction (WAXD) results demonstrate CBAAnPETs remain good crystallization ability. Owing to the two types of cross-linking reactions, i. e. the reactions between Schiff base (CHN-) and cyano group (-Câ¡N), and among -CHN- units, CBAA plays an important role in solid phase as well as gaseous phase endowing CBAAnPETs with excellent flame retardancy. With a low CBAA content (only 6.7â¯mol%), the copolyesters self-extinguish in 5â¯s with no melt drips in UL-94 vertical test, and its LOI value also increases to 31.0%. The peak heat release rate and total smoke release of the copolyesters obtained from cone calorimetry also observably decrease.
Related Topics
Physical Sciences and Engineering
Chemistry
Organic Chemistry
Authors
Jia-Ning Wu, Zi-Hao Qin, Lin Chen, Bo-Wen Liu, Xiu-Li Wang, Yu-Zhong Wang,