• Fibers and Polymers
• /
• v.2 no.2
• /
• pp.75-80
• /
• 2001

The thermal degradation of poly(ethylene terephthalate-co-isophthalate)s (PETIs) is investigated by using isothermal thermogravimetric analysis at the temperature range of 280-31$0^{\circ}C$. The degradation rate of PETIs is increased as the mole ratio of ethylene isophthaloyl (EI) units in PETIs increases. The activation energies for the thermal degradation of poly(ethylene terephthalate), PETI(5/5), and poly(ethylene isophthalate) are 33.4, 16.6, and 8.9 kcal/mole, respectively. The degradation rate of PETIs is influenced by their volatile cyclic oligomer components formed during the polymerization and the thermal degradation. It is simulated by the rotational isomeric state model that the content of cyclic dimer in PETIs, which is the most volatile cyclic oligomer component, increases with the EI units in PETIs.

• Textile Coloration and Finishing
• /
• v.10 no.1
• /
• pp.20-24
• /
• 1998

Oligomeric extracts of poly(ethylene terephthalate-co-ethylene isophthalate)s [(PET/EI] are analyzed by high performance liquid chromatography(HPLC) and nuclear magnetic resonance spectroscopy (NMR). Existence of separated peaks for small cyclics of trimer and tetramer gives the existence of structural isomeric forms. NMR confirms that cyclization of PET/EI occurs more easily at the site of isophthaloyl unit.

• Proceedings of the Korean Fiber Society Conference
• /
• 1991.06b
• /
• pp.33-34
• /
• 1991

• Proceedings of the Korean Fiber Society Conference
• /
• 2003.04a
• /
• pp.333-334
• /
• 2003

Poly(trimethylene terephthalate)(PTT)는 결정화 속도가 빠른 결정성 고분자로 최근들어 섬유화에 성공한 이후 활발한 연구가 진행되고 있다. 그러나 U의 빠른 결정화속도와 높은 결정화도 때문에 제품 제조시 곤란을 받고 있다. 한편, PET의 경우 비결정성 고분자인 poly(ethylene isophthalate)(PEI)를 공중합시켜 유리전이온도와 결정화도를 낮추고 결정화속도를 늦추어 PET 섬유의 염색성 및 투명도를 향상시키고, 저온에서의 공정처리를 가능하게 할 수 있다[1-3]. (중략)