ISSN:
0449-2951
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
A series of polyesters of trans-1,4-cyclohexanedimethanol was prepared and the melting points compared with those of the analogous series of polyesters prepared from p-xylylene glycol. Only slight differences in melting points were noted between the corresponding pairs of polyesters prepared from a single aliphatic dicarboxylic acid and from the two glycols. However, polyesters derived from aromatic dibasic acids and trans-1,4-cyclohexanedimethanol melt at a higher temperature than the corresponding polymer from p-xylylene glycol. The probable molecular configuration of polyesters based on trans-1,4-cyclohexanedimethanol is discussed. It is suggested that the diol moiety in the polyester can adopt a slightly contracted conformation so that the oxygen-oxygen distance is less than in polyesters derived from p-xylylene glycol. This, together with the similar degree of rigidity and symmetry of the trans-1,4-cyclohexylene and p-phenylene ring systems, is employed to explain the observed melting points. Polyesters prepared from cis-1,4-cyclohexanedimethanol are also described. As expected from the lower degree of symmetry of the diol, these polyesters have lower melting points than the analogous compositions prepared from trans-1,4-cyclohexanedimethanol. Polyesters of cis-1,4-cyclohexanedimethanol and trimethylene glycol have similar melting points. It is suggested that a cis-1,4-cyclohexylene ring and a methylene group have a similar effect on the melting point of a polyester. Copolyesters of cis- and trans-1,4-cyclohexanedimethanol with terephthalic acid do not form a minimum melting composition. Instead, they show a continuous change of melting point from that of the polyester prepared from one stereoisomer to that of the polymer prepared from the other isomer.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1964.100020508
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