Reports & Comments - "Predicting Polymer Stability" - ACS Publications

the thermal stability of metal com- plexes of 8-hydroxyquinolineand other types of coordination com- ... Brookfield viscometer can be valuable to you,...
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I&EC REPORTS

PREDICTING POLYMER STABILITY

rhermogravimetric analyses in vacuum olve the problem of inconsistent reults from tests to predict thermal tability in certain coordination polyzers

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Contradictory results reported fox he thermal stability of metal comilexes of 8-hydroxyquinoline anc Ither types of coordination com. ,ounds apparently result from mak. ng the weight-loss analyses in air ccording to E. Horowitz of thc qational Bureau of Standards anc ’rofessor T. P. Perros of Georgc Yashington University. Comparison of results obtainec n air and those obtained in vac ium disclosed a consistent relatior )etween the thermal stability of tht :oordination polymers and tht itomic number of the central metal Turther experiments conductad b! qorowitz and Perros, in which di ialent manganese, cobalt, nickel :opper, and zinc were combine( uith bis(8-hydroxy-5-quinolyl)-meth me, purified, and subjected tc ieating from room temperature tc 1000” C. in a vacuum chambe mm. Hg) equipped with ai :lectronic balanca, also yielded con .istent results. Evaluation of th’ decomposition temperatures for a1 If the coordination polymers showec :hat their thermal stabilities hac :he sequence: Mn > Co > Ni > Cu > Zn. The average values of the de :omposition temperatures wer plotted against the atomic number c the central metal and yielded linear relationship for all metal except zinc. The departure c zinc from the linear relationship i Explained on the basis of the periodi properties of the metal. These studies should provide mor understanding of factors governin the properties of coordination poly mers and may lead to polymer with better heat resistance. I

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VOL. 5 6

NO. 4

APRIL

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