D. Liaw, Hung-Ping Huang, Pei-Nan Hsu
May 15, 2002
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0
Influential Citations
4
Citations
Journal
Polymer Journal
Abstract
The five benzene rings-containing diamine, α,α’-bis[3,5-dimethyl-4-(4-aminophenoxy)phenyl]-1,4-diisopropylbenzene (BDAPD) was prepared by the aromatic nucleophilic substitution of α,α’-bis(4-hydroxy-3,5-dimethylphenyl)-1,4-diisopropylbenzene with 1-chloro-4-nitrobenzene, and subsequent hydrogenation of the intermediate dinitro compound. The diamine was reacted with various aromatic dicarboxylic acids to prepare a series of new polyamides. The polyamides were produced with high yield and inherent viscosities of 0.68–0.94 dL g-1. The wide-angle X-Ray diffraction diagrams revealed that all the polyamides showed amorphous character. All of the polyamides showed excellent solubility in a variety of solvents such as N-methyl-2-pyrrolidinone, N,N-dimethylacetamide, N,N-dimethylformade, dimethyl sulfoxide, pyridine, cyclohexanone, and tetrahydrofuran. These five benzene rings-containing polyamides had better solubility than those containing only one isopropylidene unit or a hexafluoroisopropylidene linkage in the repeating unit of polyamide backbone. These polyamides had glass transition temperatures (Tg’s) between 237–256°C. The thermogravimetric analyses demonstrated that almost all of the polymers were stable up to 400°C, and the 10% weight loss temperatures were recorded in the range 437–452°C and 447–463°C in nitrogen and air atmosphere, respectively.