THE RADIATION-CHEMISTRY OF POLY(ARYLENE ETHER PHOSPHINE OXIDE)S

被引:9
作者
HOPEWELL, JL
HILL, DJT
ODONNELL, JH
POMERY, PJ
MCGRATH, JE
PRIDDY, DB
SMITH, CD
机构
[1] UNIV QUEENSLAND,DEPT CHEM,POLYMER MAT & RADIAT GRP,BRISBANE,QLD 4072,AUSTRALIA
[2] VIRGINIA POLYTECH INST & STATE UNIV,DEPT CHEM,BLACKSBURG,VA 24061
[3] VIRGINIA POLYTECH INST & STATE UNIV,SCI & TECHNOL CTR HIGH PERFORMANCE POLYMER ADHES,NSF,BLACKSBURG,VA 24061
基金
澳大利亚研究理事会;
关键词
D O I
10.1016/0141-3910(94)90199-6
中图分类号
O63 [高分子化学(高聚物)];
学科分类号
070305 ; 080501 ; 081704 ;
摘要
Electron spin resonance spectroscopy (ESR) was used to study the free radicals produced on gamma-irradiation of selected poly(arylene ether phosphine oxide)s (PEPO). Both neutral and anionic free radicals were detected after irradiation at 77K. Thermal annealing of the radicals resulted in the identification of two decay regions; between 77 and 200K and above 240K, corresponding to the decay of radical anions and neutral radicals respectively. Photolysis with visible wavelengths was used to detrap, and so identify, anionic radicals. The presence of two species of radical anions was inferred by inspection of the radical decay curves and the spectra of the radicals lost on photolysis. The neutral free radicals detected were identified as phenoxyl-type radicals formed by the homolytic scission of ether bonds int he polymer. P-31 NMR of the polymers after irradiation showed broadening of the main peak to higher chemical shift, suggesting crosslinking, probably at the phenyl side-chain. Viscosity measurements showed a slight decrease int he limiting viscosity numbers for solutions in dichloromethane, and therefore in the molecular weight of the polymers, with increasing dose. Main chain scission and crosslinking occur simultaneously in the polymers, with chain scission dominant over crosslinking [G(S) > 4G(X)]. At 77K the radical yield increased with dose in a similar fashion for all three polymers, but at room temperature the radical yields for a given dose increased in order of the radio of ether bonds to aromatic groups in the polymer, that is, in the order biphenol < bisphenol-A < hydroquinone PEPO.
引用
收藏
页码:293 / 299
页数:7
相关论文
共 16 条
[1]  
GEOFFROY M, 1974, MOL PHYS, V28, P839, DOI 10.1080/00268977400102191
[2]   ELECTRON SPIN RESONANCE STUDIES OF POLYCARBONATE IRRADIATED BY GAMMA-RAYS AND ULTRAVIOLET LIGHT [J].
HAMA, Y ;
SHINOHAR.K .
JOURNAL OF POLYMER SCIENCE PART A-1-POLYMER CHEMISTRY, 1970, 8 (03) :651-&
[3]  
HEILAND K, IN PRESS POLYM ADV T
[4]   RADIATION DEGRADATION OF STATISTICAL TERPOLYMERS OF 2 AROMATIC DIOLS WITH DIPHENYL SULFONE [J].
HILL, DJT ;
LEWIS, DA ;
ODONNELL, JH ;
POMERY, PJ ;
HEDRICK, JL ;
MCGRATH, JE .
POLYMER INTERNATIONAL, 1992, 28 (03) :233-237
[5]  
KEYSER RM, 1972, RAD CHEM MACROMOLECU, V1, P149
[6]  
LEWIS DA, 1989, THESIS U QUEENSLAND
[7]  
LYONS AR, 1972, MAKROMOLEKUL CHEM, V157, P103
[8]   FACTORS CONTROLLING SITE OF ELECTRON-CAPTURE AND MODE OF DISSOCIATION FOLLOWING MOLECULAR ELECTRON-CAPTURE - ELECTRON-SPIN RESONANCE STUDY [J].
MISHRA, SP ;
SYMONS, MCR .
JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS, 1974, (15) :606-607
[9]   HYDROXYL RADICAL REACTIONS WITH PHENOLS AND ANILINES AS STUDIED BY ELECTRON-SPIN RESONANCE [J].
NETA, P ;
FESSENDE.RW .
JOURNAL OF PHYSICAL CHEMISTRY, 1974, 78 (05) :523-529
[10]  
ODONNELL JH, 1970, PRINCIPLES RAD CHEM, P39