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- 검색키워드
- 주제어 : poly(trimethylene naphthalate) (검색결과 5 건)
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최재원,이한섭,김영호,Choi, Jae-Won,Lee, Han-Sup,Kim, Young-Ho 한국섬유공학회 2006 한국섬유공학회지 Vol.43 No.6
Poly(trimethylene terephthalate) (PTT)/poly(trimethylene naphthalate) (PTN) (50/50, weight ratio) blend films (T5N5) with amorphous state were prepared by melt-pressing of solution blended powders at $260^{\circ}C$ for various times and quenching them in liquid nitrogen. Homo PTT and PTN films were also prepared by the same method. Small angle X-ray scattering (SAXS) measurements during the heating process were carried out using synchrotron X-ray source to investigate the changes in microcrystalline structure of the PTT, PTN and T5N5 films. From the electron density correlation functions obtained from SAXS patterns, long period (L), lamella thickness ($I_c$), and amorphous layer thickness ($I_a$) were calculated. Long periods of the amorphous films began to increase at around crystallization temperature of the samples. The increase in both $I_c\;and\;I_a$ attributed to the increase of L.L of PTN film is larger than that of PTT. L of T5N5 exhibited values between those of PTT and PTN film and it increased with heat treatment time at $260^{\circ}C$.
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Choi, Jae-Won,Kwark, Young-Je,Kim, Young-Ho The Korean Fiber Society 2007 Fibers and polymers Vol.8 No.3
Poly(trimethylene terephthalate) (PTT)/poly(ethylene naphthalate) (PEN) blends of various compositions were prepared by the solution-blending and melt-blending methods. The changes in miscibility and crystallization behaviors of the blends upon thermal treatment above the melting temperature of the blends at $280^{\circ}C$ were investigated by using DSC, DMA, $^1H$ NMR, and SAXS analyses. Without any thermal treatment, the blend systems were not miscible, and the thermal transitions, such as glass transition, cold crystallization, and crystal melting of the individual components were observed in the DSC and DMA analyses. With thermal treatment, though, they became miscible as the thermal transitions of each component disappeared and single glass transition peaks were observed in the thermal analysis. The chain randomness determined using $^1H$ NMR spectroscopy revealed that thermal treatment at $280^{\circ}C$ for more than 30 min brought about transesterification reactions between the PTT and PEN segments resulting in an increase in their miscibility. These results were confirmed by the small angle X-ray analysis conducted to determine the long period (L), the thickness of the crystalline lamella stack ($l_c$), and the thickness of the amorphous region ($l_a$). After short thermal treatment, the melt-blended sample followed the values for the individual components. However, with extended thermal treatment, the blend became homogeneous, possessing different crystalline morphologies which resulted in different values of L, $l_c$, and $l_a$.
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$^1H-NMR$과 WAXS를 이용한 폴리(트리메틸렌 테레프탈레이트)/폴리(트리메틸렌 나프탈레이트) (50/50) 블렌드의 에스터 교 환반응 연구
최재원,오태환,김영호,Choi, Jae-Won,Oh, Tae-Hwan,Kim, Young-Ho 한국섬유공학회 2005 한국섬유공학회지 Vol.42 No.5
Poly(trimethylene terephthalate) (PIT) and poly(trimethylene naphthalate) (PTN) blends of 50/50 weight ratio, T5N5, were prepared by solution blending-precipitation method, and the effect of melting time on the degree of randomness, sequence length, and crystalline structure of melt-pressed blends obtained by melting T5N5 on a hot stage at $260^{\circ}C$ for different times and quenching into liquid nitrogen was studied using DSC, $^1H-NMR$ and WAXS. The T5N5 blend showed two $T_gs$ corresponding to that of PTT and PTN, which indicated that PTT and PTN were immiscible. But the melt-pressed blends melted at $260^{\circ}C$ for 2 minutes or more showed single $T_g$ indicating that the system became miscible. $^1H-NMR$ analysis confirmed that the blends became block copolymers and that the degree of randomness increased as melting time increased. The sequence length of PTT component was larger than that of PTN in the resultant copolymer. Although PTT and PTN were present in the same amount in the blend, PTT component crystallized more easily than the PTN component due to the larger block length of PTT. The crystalline structure of the component polymers was the same as that of homopolymers. The WAXS patterns showed that the crystalline structure of PTN in the melt-pressed blends was $\beta-form$ when they were annealed at $180^{\circ}C$ but it was a-form when annealed at $140^{\circ}C$, exhibiting the same behavior as homo PTN.
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Jeong, Young-Gyu,Jo, Won-Ho,Lee, Sang-Cheol The Korean Fiber Society 2004 Fibers and polymers Vol.5 No.3
Poly(trimethylene terephthalate-co-trimethylene 2,6-naphthalate)s (P(TT-co-TN)s) with various copolymer composition were synthesized, and their chain structure, thermal property and crystalline structure were investigated by using $^1$H-NMR spectroscopy, differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD), respectively. It was found from sequence analysis that all the P(TT-co-TN) copolymers synthesized have a statistical random distribution of TT and TN units. It was also observed from DSC thermograms that the glass transition temperature increases linearly with increasing the TN comonomer content, whereas the melting temperature of copolymer decreases with increasing the corresponding comonomer content in respective PTT- and PTN-based copolymer, showing pseudo-eutectic melting behavior. All the samples melt-crystallized isothermally except for P(TT-co-66 mol % TN) exhibit multiple melting endotherms and clear X-ray diffraction patterns. The multiple melting behavior originates from the dual lamellar population and/or the melting-recrystallization-remelting. The X-ray diffraction patterns are largely divided into two classes depending on the copolymer composition, i.e., PTT and PTN $\beta$-form diffraction patterns, without exhibiting cocrystallization.
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편광현미경을 이용한 PTT/PTN 블렌드의 등온결정화 거동 분석
최재원,차희철,김영호,Choi, Jae-Won,Cha, Hee-Cheol,Kim, Young-Ho 한국섬유공학회 2005 한국섬유공학회지 Vol.42 No.6
Isothermal crystallization behaviors of poly(trimethylene terephthalate) (PTT), poly(trimethylene naphthalate) (PTN), and PTT/PTN blends were analyzed using a polarizing microscope equipped with a hot-stage. As the melting time at $260^{\circ}C$ of PTT/PTN blends increased, the crystallization proceeded slowly due to the copolymer formation which resulted from the ester interchange reaction at the elevated temperature. PTT and m-rich blends formed spherulites over the temperature range of experiment, but PTN formed spherulites only at lower crystallization temperatures such as $150^{\circ}C$. PTN and PTN-rich blends formed distorted spherulites at high temperatures such as $180^{\circ}C$, which seemed to result from the $\beta-crystal$ formation of PTN at that temperature. The radial growth rate of the spherulite formed during the crystallization was obtained by the measurement of radii of the spherulites. The radial growth rate decreased as PTN content in the blends increased.
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