• Fibers and Polymers
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• v.1 no.2
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• pp.83-91
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• 2000

Thermotropic liquid crystalline polymer made up of poly(p-hydroxybenzoate) (PHB)-poly(ethylene terephthalate)(PET) 8/2 copolyester, poly(ethylene 2,6-naphthalate) (PEN) and PET were mechanically blended to pursue the liquid crystalline phase of ternary blends. Complex viscosities of blends decreased with increasing temperature and PHB content. DSC thermal analysis indicated that glass transition temperature (Tg) and melting temperature (Tm) of blends increased with increasing PHB content. Both tensile strength and initial modulus increased with raising PHB content and take-up speed of monofilaments. In the WAXS diagram, only PEN crystal reflection at 2Θ=$15.5^{\circ}C$ appeared but PET crystal reflection was not shown in all compositions. The degree of transesterification and randomness of blends increased with blending time but sequential length of both PEN and PET segment decreased.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.343-344
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• 2003

폴리에틸렌 나프탈레이트(PEN)는 열적 및 물리적 특성이 우수한 고분자로서 포장재료, 필름, tire cord 등으로 그 이용범위가 확대되고 있는 고분자이다[l]. 그러나 강직한 분자사슬을 가지고 있는 PEN은 고결정성과 소수성 둥으로 인해 흡습성, 제전성 및 염색성이 좋지 못하고 성형가공이 어려운 단점도 있다. 이미 동종계열인 PET의 경우 그러한 단점을 개선하고자 합성반응시 diol과 같은 제 3의 단량체를 사용하여 공축합하는 연구[2-3]가 시도된바 있으나 PEN의 경우 아직 이에 관한 연구보고가 없는 실정이다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.167-168
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• 2003

Dimethyl-2,6-naphthalenedicarboxylate(2,6-NDC)와 ethylene glycol(EG)로부터 유도되는 폴리에틸렌 나프탈레이트(PEN)는 폴리에틸렌 테레프탈레이트(PET)보다 열적 및 기계적 특성이 우수한 열가소성 고분자이며[1-2], 폴리에틸렌 글리콜(PEG)은 diol기를 함유한 친수성 고분자로서 의약품 및 기타 가공제로 널리 쓰이는 물질이다. 이미 PET는 이러한 PEC를 PET 합성과정에서 공단량체로 사용해 공중합시킴으로서 친수성을 갖는 PET로 개질하고자 하는 연구[3-4]가 다수 보고되어 왔으나, PEN의 경유는 아직 이에 관한 연구보고가 없는 실정이다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.101-104
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• 2002

Since the family of poly(m-methylene 2, 6-naphthalate) (PmN) with the chemical structure as shown in Figure 1(a) was first reported in 1969, the polymers belonging to this family have attracted considerable interests in the commercial and academic points of view due to realization of large-quantity production of 2, 6-naphthalenedicarboxylic acid. The commercially available polymers among this family are poly(ethylene 2, 6-naphthalate) (PEN, m=2) and poly(butylene 2, 6-naphthalate) (PBN, m=4). (omitted)

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.52-55
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• 2003

Poly (ethylene 2, 6-naphthalate) (PEN) has been used for a high performance engineering plastics such as fiber, film, and packaging, because of excellent physical properties and outstanding gas barrier characteristics [1-2]. However, the application of PEN is limited because PEN exhibits a relatively high melt viscosity. Recently, many researches for organic/inorganic composites by applying nano-particles to the polymer matrix have been carried out [3], and the nano-particles exhibited greatly improved mechanical and rheological properties [4]. (omitted)

• Proceedings of the Korean Fiber Society Conference
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• 1994.04a
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• pp.111-112
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• 1994

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.83-86
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• 2003

최근 들어 poly(trimethylene terephthalate)(PTT)를 다른 고분자와 블렌딩시켜 특성 변화를 검토한 논문이 많이 발표되고 있는데 PTT와 블렌딩하는 고분자는 주로 PET와 같은 Poly(alkylene terephthalate)계 고분자들이다[1,2]. 나프탈렌환을 갖는 Poly(alkylene naphthalate)계 고분자를 PTT와 블렌딩한 연구는 PTT/poly(ethylene naphthalate)(PEN) 블렌드계[3] 정도가 보고되고 있으며, PTT를 다른 나프탈렌계 고분자와 블렌딩한 연구 결과는 거의 없는 실정이다. (중략)

• Textile Coloration and Finishing
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• v.11 no.5
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• pp.44-54
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• 1999

Poly(ethylene 2,6-naphthalate), PEN, is a relatively well-known polymer used for engineering purposes. Naphthalene ring provides rigidity to the polymer backbone, thus, it elevated the glass transition temperature and enhanced mechanical properties. The structure and properties of PEN affect a processing conditions severely, and the high-thermal stability have been had a poor thermal processibility. Hence, the basic mechanism of solvent drawing, is very much the same as that of thermal drawing from glassy state since both involve the inducement of segmental mobility. The former achieves the goal by use of chemical energy, and the latter does so by use of thermal energy. Generally, the sorption of the solvent by the polymer has a plasticizing effect, and leads to a lowering of the glass transition temperature, $T_g$. In this paper, the dynamic viscoelasticity behavior in liquid-drawing process of an unoriented amorphous PEN films were investigated using Rheovibron. The results are as follows ： (1) For the drawing in silicone oil, the drawing below $T_g$. had $\alpha{2}$-dispersion due to an inhomogeneous taut structure. (2) For the drawing in water, the inhomogeneous taut structure reduced by the effect of plasticization even below $T_g$. (3) For the drawing in butanol, the only aliphatic segment in PEN have some molecular mobility but the mobility of the aromatic segment having naphthalene ring is nearly impossible. (4) For the drawing in dioxane/water mixing solvent, the solvent effect is complementary each other and accordingly the entire molecular conformation have stable state. (5) For the drawing in dioxane/butanol mixing solvent, the inhomogeneity of the taut structure and the aromatic segment increase with increasing the temperature and this tendencies correspond with that of the draw ratio.

• Macromolecular Research
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• v.12 no.1
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• pp.94-99
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• 2004

We have performed Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) studies on blends of poly(vinyl phenol) (PVPh) with poly(n-alkylene 2,6-naphthalates) containing alkylene units of different lengths. The results indicate that each poly(ethylene 2,6-naphthalate) (PEN) and poly(trimethylene 2,6-naphthalate) (PTN) blend with PVPh is immiscible or partially miscible, but blends of poly(butylene 2,6-naphthalate) (PBN) with PVPh are miscible over the whole range of compositions in the amorphous state. FTIR spectroscopic analysis confirmed that significant degree of intermolecular hydrogen bonding occurs between the PBN ester carbonyl groups and the PVPh hydroxyl groups. The large difference in the degree of mixing in these blend systems is described in terms of the effect that chain mobility has on the accessibility of the ester carbonyl functional groups toward the hydroxyl groups of PVPh, which in turn impacts the miscibility of these blends.

• Polymer(Korea)
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• v.36 no.6
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• pp.733-738
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• 2012

The effect of glass bead and glass fiber on the enhancement of dimensional stability in poly(ethylene naphthalate) (PEN) flexible substrate for photovoltaic devices has been studied. It was found that the coefficient of thermal expansion (CTE) and the optical transmittance decreased with increasing inorganic filler content. In addition to filler contents, the size and size distribution of fillers are the other important factors to improve CTE and optical transmittance of PEN film. Our results showed that the optimum filler content was found to be about 5 wt% to enhance the dimensional stability of PEN by more than 50% with maintaining the optical transmittance over 85% for the flexible substrate.