• Korean Chemical Engineering Research
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• v.47 no.3
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• pp.316-320
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• 2009

UV curable hard and color coatings were formed on polycarbonate(PC) films. The coating materials were composed of a commercially available end-capped polyester(EB830), diacrylate monomer(HDDA), silicon acrylate, photoinitiator, and organic dye as a coloring agent. The surface properties of coating films were evaluated, and the influences of the compositions of coating materials were investigated. The coating films showed high transmission and good adhesion between coating layer and PC substrate. And the coating films exhibited higher hardness than bare PC film. The coating films with various colors were obtained by wet process, and the clear and color window lenses for mobile phone were prepared successfully.

• Polymer(Korea)
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• v.26 no.3
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• pp.335-343
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• 2002

Blend resin (PET/PETG 70/30 blend) of poly (ethylene terephthalate) (PET) and poly (ethylene terephthalate glycol) (PETG) of weight percent 70/30 was prepared by a twin-screw extruder. Undrawn films of the blend and pure PETG were made by melt-press in hot press. Drawn films were made by capillary rheometer. Crystallinity, shrinkage, thermal, dynamic mechanical, and mechanical properties of these blends and PETG drawn films were investigated by wide angle X-ray diffractometer, dry oven, DSC thermal analyzer, and tensile tester. The crystallinity and density of these films increased with increasing draw ratio and draw rate but decreased with increasing draw temperature. The crystallinity and density of the blend films were higher than those of PETG films. The tensile strength and tensile modulus of these drawn alms increased with increasing draw ratio and draw rate but decreased with increasing draw temperature. The tensile strength and tensile modulus of blend films were higher than those of PETG films. Shrinkage of PETG md blend films decreased with draw ratio and draw rate. Shrinkage of undrawn blend film was 600% higher than that of pure PET film.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.444-447
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• 2001

Poly (trimethylene 2,6-naphthalene dicarboxylate) (PTN)은 naphthalene-based polyester의 일종으로 1969년에 Doling 와 Chester에 의하여 처음으로 합성방법이 발표되었다. 최근에 이르러 propanediol의 상업적 생산이 가능해지면서 propandiol를 사용한 polymer의 관심이 늘어나면서 PTN에 관한 연구도 여러 연구자에 의하여 다양하게 진행되고 있다. 일반적으로 결정성 고분자의 구조형성 과정에서 배향과 결정화는 상호 밀접한 관계가 있으며 배향과 결정화의 관계의 파악은 고분자 물성을 이해하는데 필수적이다. (중략)

• Macromolecular Research
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• v.16 no.7
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• pp.651-658
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• 2008

Poly(butylene succiate) (PBS), poly(butylene succinate-co-L-lactate) (PBSL), and poly(butylene succinate-co-6-hydroxycaproate) (PBSCL) polymers were degraded by lipase $PS^{(R)}$, and the enzymatic degradation mechanism of PBS was analyzed in detail. The enzymatic degradation of PBS gave 4-hydroxybutyl succinate (4HBS) as the main product. An exo-type hydrolysis mechanism was proposed based on this observation. The terminal chain of PBS had conformational similarity to ordinary tri- and diglycerides and could be incorporated as a substrate in the active site of this lipase. The surface adsorption of the lipase was much larger on PBS and its copolymer films than on the other polyester films because the lipase adhered quite strongly to the polymer terminal through a specific adsorption mechanism. Kinetic analysis showed that the total number of surface adsorption points per unit area of PBSL and PBSCL copolymers was larger than that of the PBS homopolymer.

• Textile Coloration and Finishing
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• v.4 no.4
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• pp.110-116
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• 1992

For the modification of PET surface, Perfluoropropene and Methyl alcohol were LT-plasma polymerized on the PET fabrics as thin films by means of 13.56 MHz radio frequency generator. The surface properties of PET fabrics were modified from hydrophobic to hydrophilic by application of the postplasma reaction of thin films. The evidence of the modification was identified by observation of the presence of hydroxy group in IR spectrum and the evaluation of degree of hydrophilicity was performed by measuring frictional static voltage of PET fabric with cotton fabric. For the case of modification by PFP, the result performed at the condition of 25 W, 70 m torr has shown to be effective, and for MeOH, result performed at the condition of 25 W, 100 m torr effective. The effect of hydrophilic surface modification of MeOH plasma polymer was superior to that of PFP-plasma polymer.

• Journal of Adhesion and Interface
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• v.22 no.2
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• pp.39-46
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• 2021

Waterborne polyurethanes (WPU) was synthesized using polyester polyol and polycarbonate polyol containing 3-Methyl-1,5-pentanediol (MPD) in a branched structure. To compare physical properties, WPUs were synthesized using polyester polyol obtained from 1,4-butanediol (BD) and adipic acid and polycarbonate polyol obtained from 1,6-hexane diol (HD)/ 1,4-butanediol (BD). This study investigated the effect of polyol molecular structure (molecular structure in soft segments) on the physical properties of WPUs. In the case of WPUs synthesized using polyols containing MPD, 100% modulus and tensile strength were lower than that without MPD, and elongation was higher. The transparency of WPU films with MPD were slightly better than WPU films without MPD.

• Polymer(Korea)
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• v.25 no.2
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• pp.208-217
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• 2001

PET/BPA copolymer of terephthalic acid, bisphenol-A and ethylene glycol was melt-pressed and quenched in ice water. This copolymer film was drawn by capillary rheometer. Shrinkage, crystallinity, morphology, thermal, dynamic mechanical, and mechanical properties of these copolymer films were investigated. The PET/BPA copolymer film exhibited T$_{m}$ lower than that of PET film. The crystallinity and density of these drawn copolymer films increased with draw ratio and draw rate but decreased with draw temperature. The tensile strength and tensile modulus of the copolymer films increased with draw ratio but decreased with draw temperature. Shrinkage of the drawn copolymer film decreased with draw ratio and draw rate.e.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.224-232
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• 2015

The effects of cold plasma (CP) treatments on the physicochemical and biodegradable properties of a corn biomass-containing polyester (CBPE) film were studied. The CBPE film was treated with CP generated by $N_2$, $O_2$, He, Ar, or dry air at 400-900 W and 667 Pa for 10-40 min. The glass transition temperature of the CBPE film ($-30.2--28.6^{\circ}C$) was not affected by the CP treatment, while the elastic modulus and water vapor permeability decreased (p<0.05). The ink printability was improved by the treatment and the improved printability was maintained during storage for 56 days at room temperature. Roughness of the film increased after treatments and the level of roughness appeared to increase during storage. Heat and microbial biodegradability of the CBPE film was improved by the air-CP treatment (p<0.05). These results have demonstrated the potential of applying CP treatments to improve the flexibility, printability, and biodegradability of CBPE films.

• Journal of the Korean Applied Science and Technology
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• v.2 no.1
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• pp.19-23
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• 1985

In order to know the quality changes of the fat and oil foods packed in plastics film by the sunlight, we examined the sunlight transmitting rate by the kind of films and measured the acid value and peroxide value according to it. The results obtained were as follows : 1. The sunlight transmitting rate of various films was explained especial permeability under the wavelength of less than 300nm, but it marked a regular form under that of more than 30nm. 2. The vacuum evaporation film with aluminum on the polyester shuts off most of the sunlight, therefore, it has the best effect that keeps the fats and oils off rancidity. 3. The sunlight transmitting rate of the white color printing film drops about 80% as compared with not printing. 4. The preventive power against the rancidity of fats and oils is PET/Al, PET, PE, nylon and OPP film in that order. The changes of peroxide value and acid value were approximately the same as that of the sunlight transmitting rate.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.243-246
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• 2003

Poly(butylene terephthalate)(PBT) is an important engineering polyester. It crystallizes much more easily and faster than PET. And these crystallization properties determine its use as an injection molding resin. Although it is more extensive than PET, its crystallization can be controlled much more easily during processing. General electric (Schenectady, NY) is the main producer of PBT films. Its production capacity was 3-5million pounds per year in 1987. (omitted)