Manipulating the Properties of Poly(1,4-Cyclohexylenedimethylene Terephthalate) (PCT) Just by Tuning Steric Configuration of 1.4-Cyclohexanedimethanol (CHDM)

The properties of poly(1,4-cyclohexylenedimethylene terephthalate) (PCT) are manipulated only by tuning the steric configuration of 1,4-cyclohexanedimethanol (CHDM). The chemical structures and compositions of PCTs are confirmed by nuclear magnetic resonance ( 1 H NMR and 13 C NMR) before their thermal and mechanical properties are investigated by differential scanning calorimeter, thermogravimetric analyzer, and dynamic mechanical analysis. Results show that the ratio of cis - to trans -CHDM in PCTs has significant influences on their properties. The melting temperature of PCTs is varied from 251 to 313 °C, and the glass transition temperature is increased from 73 to 92 °C when the content of trans -CHDM in PCTs is increased from 10% to 96%. In addition, the crystallizability of PCT is also increased with the content of trans -CHDM. However, its thermal stability is decreased seriously when the melting temperature of PCT is higher than 280 °C. It is concluded that when the content of trans- CHDM is lower than 50% (PCT-10, PCT-28, and PCT-46), the balance of melting temperature, glass transition temperature, and thermal stability for PCT can be achieved. Just by varying the cis / trans ratio of CHDM, rather than the addition of other components, the properties of PCT can be manipulated.