ISSN:
0887-624X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Aromatic polyesters connected by methylene groups were synthesized. Two pairs of aromatic diacid chlorides, 3,3′-methylenedibenzoyl chloride and 4,4′-methylenedibenzoyl chloride were each polymerized via interfacial polycondensation with 2,2-bis(4-hydroxyphenyl)propane (bisphenol A), 3,3′-methylenediphenol, and 4,4′-methylenediphenol. For comparison, 3,3′-carbonyldibenzoyl chloride and 4,4′-carbonyldibenzoyl chloride were similarly polymerized with bisphenol A. Substitution of meta,meta' oriented phenylene groups for para,para' oriented phenylene groups had a significant and cumulative effect in reducing the glass transition temperatures of the polymers, thereby enhancing their processability. In air the methylene groups of the polyesters undergo oxidation and crosslinking at elevated temperatures. Electron beam irradiation of thin films of the methylene-linked polyesters at room temperature resulted in some chain extension and crosslinking, as evidenced by increased solution viscosity and gel formation. Irradiation at a temperature near or above the glass transition temperatures of the polymers greatly enhanced the tendency for the polymers to crosslink.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pola.1986.080240508
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