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>Wholly aromatic polyamide‐hydrazides I. A viscometrical method for monitoring of condensation polymerization reactions
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Wholly aromatic polyamide‐hydrazides I. A viscometrical method for monitoring of condensation polymerization reactions
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机译：Wholly aromatic polyamide‐hydrazides I. A viscometrical method for monitoring of condensation polymerization reactions
AbstractA simple and practical viscometrical method for monitoring the progress of condensation polymerization reactions was investigated. It consisted of following the reaction mixture capillary flow time as a function of molar ratio of the reacting monomers in a polymerization reaction performed by gradual addition of terephthaloyl chloride (TCI) into solution ofp‐aminobenzhydrazide (ABH) inN,N‐dimethylacetamide (DMA) solvent. The results obtained were compared to those from dilute solution viscometry and light scattering studies. This indicated that the observed increase in the reaction mixture capillary flow time accurately enough reflected the buildup of the molecular weight of growing polymer product during the course of this course of this condensation polymerization reaction and that this viscometrical monitoring method provided an extremely practical tool for controlled preparation of the polymers of high and/or predetermined molecular weights by this synthetic route. A series of para‐oriented, wholly aromatic amide–hydrazide polymers from ABH and TCl, was also characterized by viscometry and light scattering in DMA at 20°C, and the following viscosity–molecular weight relationship was determined: η = 5.16 ×
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