• Elastomers and Composites
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• v.44 no.4
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• pp.447-454
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• 2009

We synthesized polyester-diol containing Cloisite 30B which is exfoliated during the synthesis. First, esterification was conducted with excess adipic acids and two 2-hydroxyethyl groups of the tertiary ammonium tethered to Cloisite 30B silicate layer. Due to the small molecular size of adipic acid ($d{\approx}3.0\;{\AA}$, $L{\approx}9.3\;{\AA}$), it penetrated into the interlayer of Cloisite 30B, reacted with the 2-hydroxyethyl groups, and produced the tertiary ammonium that has the two ethyl-ester adipic acid groups, one methyl group, and one hydrogenated alkyl group. Through the esterification, the molecular size of the tertiary ammonium increased and as the result, the basal space of Cloisite 30B increased from $18.4\;{\AA}$ to more than $58.3\;{\AA}$. The produced ethyl-ester adipic acid and unreacted adipic acid reacted with excess diethylene glycol ([COOH]/[OH]${\approx}0.6$) to be polyester-diol. The COOH conversion calculated from the acid value of the reactant mixture was 94%. The number average molecular weight and PDI of the produced polyester-diol were 830 g/mol and 1.2, respectively.

• Elastomers and Composites
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• v.48 no.3
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• pp.190-194
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• 2013

In this study, sebacic acid made from castor oil was used as monomer with isophthalic acid and glycols for polyester polyol synthesis. Polyurethane adhesive was synthesized from the various polyester polyol. From the result of adhesion strength test, polyester polyol made from sebacic acid showed better adhesive force than that of adipic acid due to higher cohesive energy. Branched glycol containing methyl group represented better adhesion than linear glycol. In the chain extender, adhesion strength increased going from PG, EG, BD. From the measurement of TGA, BD showed the best heat stability, and followed by PG, EG. Glass transition temperature increased in the order PG, EG, BD by the result of DMA.

• Elastomers and Composites
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• v.46 no.1
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• pp.37-44
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• 2011

Effect of organo nanoclay (Cloisite 30B) on the polyesterification of adipic acid (AA) with diethylene glycol(DEG) was investigated with p-toluene sulfonic acid (p-TSA) (Br${\phi}$nsted acid) and butylchlorotin dihydroxide (Lewis acid) catalyst at 383 and 423 K. The initial [OH]/[COOH] molar ratio was two and the concentration of the catalysts in the reactants was 0.14 mol% based on the total reactants. The kinetics of the polyesterification was interpreted with the conversion data that was calculated from the acid values of the reactant-product mixture. The reaction rate of the polyesterification, which was catalyzed with p-TSA, exhibited the second-order dependency on AA concentration. When Butylchlorotin dihydroxide was used, the reaction rate revealed the first-order dependency on AA concentration. The activation energy of the reactions catalyzed with p-TSA and Butylchlorotin dihydroxide were calculated at 42.2 and 63.8 kJ/mol, respectively. Addition of 5 wt% Cloisite 30B to the reactant significantly diminished the activity of p-TSA, so the reaction rate decreased and the activation energy was calculated at 72.9 kJ/mol. Butylchlorotin dihydroxide catalyst maintained its activity regardless of the addition of Cloisite 30B to the reactant and the activation energy was calculated to 61.8 kJ/mol. Lewis acid catalyst, butylchlorotin dihydroxide, was more effective than Br${\phi}$nsted acid catalyst for the esterification of AA with DEG.

• Elastomers and Composites
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• v.38 no.4
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• pp.342-353
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• 2003

This work is about the development of jet-fuel resistant PVC sealant using a polyester plasticizer. PVC copolymer was compounded with adipic acid glycol(Songcizer P-3000) or DOP plasticizers. Fuel-immersed and non-immersed penetration, solubility, flow, and elongation by tensile adhesion of PVC compounds were measured. Penetration increase by fuel immersion and solubility of PVC compounds with adipic acid glycol polyester plasticizer were smaller than those of PVC compounds with DOP plasticizer. Elongation by tensile adhesion test of PVC compound containing 500 phr of Songcizer P-3000 decreased proportionally to the content of DCDP (dicyclopentadiene) base petroleum resin adhesion promoter. Calcium carbonate($CaCO_3$) filler inhibited the diffusion of fuel in all the PVC compounds and decreased the solubility of PVC compounds containing Songcizer P-3000.

• Polymer(Korea)
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• v.28 no.3
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• pp.239-244
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• 2004

Effect of lubricants on the rheological and thermal properties of poly(butylene terephthalate) [PBT] were investigated. Calcium stearate and adipic acid glycol polyester (AhGP) were used as processing lubricants for PBT. Decrease of melt viscosity was accomplished by the addition of 1 wt％ of lubricants. It was understood that melt viscosity was affected by the enhancement of chain mobility of PBT with AhGP as an internal lubricant as well as the lubricity on processing equipment developed by calcium stearate as an external lubricant. Lubricants also influenced chain scission of PBT which caused the viscosity drop as well. In addition, lubricant is resulted in the lowering of thermal stability, however, this might be minimized by adding less than 3 wt％ of calcium stearate as a lubricant. As a consequence, calcium stearate as an external lubricant is more effective to control the melt viscosity of PBT with minimizing of chain scission and thermal instability in PBT.

• Applied Chemistry for Engineering
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• v.16 no.6
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• pp.834-841
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• 2005

Polyethylene glycol esters (PEG-esters) were synthesized by condensation reaction of dicarboxylic acid such as adipic acid and sebacic acid and several PEGs. The PEG-esters were analyzed by FT-IR, $^1H-NMR$ and HPLC for structure analysis, and by GPC for molecular weight. Through the analysis of surface tension, critical micelle concentration (CMC), aluminum contact angle of water solution containing the PEG-ester, the synthetic PEG-esters are proven to exhibit surfactant properties. The surface tension ranged from 45 to 50 dyn/cm depended on the concentration and structures of the PEG-esters. The surface tension of PEG-esters with sebacic acid moiety and short polyoxyethylene unit resulted in lower value than that of PEG-ester with adipic acid moiety and long polyoxyethylene unit. The CMC of water solution containing 2.5 wt% PEG-ester with sebacic acid moiety estimated at $0.9{\times}10^{-5}{\sim}5.3{\times}10^{-3}mol/L$ depended on the structures of PEG-esters. The CMC of PEG-esters with long polyoxyethlene unit showed a higher value than that of PEG-esters with short polyoxyethylene unit. Meanwhile, the CMC of PEG-esters with adipic acid moiety was not distinct due to their high hydrophilic character. As the results of contact angle and cutting time aginst aluminum, the contact angle ranged from $45^{\circ}$ to $53^{\circ}$ depended on the concentration of PEG-esters. The cutting time of aluminum showed the shortest value at CMC, but the longest value above CMC. This fact indicates that the CMC of PEG-esters is a very important factor in drilling aluminum.

• Clean Technology
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• v.24 no.3
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• pp.190-197
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• 2018

Various waterborne polyurethanes (WPU) with three different types of polyol such as ester type polyol [adipic acid (A)/BD/3-methyl-1,5-pentandiol (MPD) and A/BD]//carbonate type polyol (C/HD/MPD, C/HD, C/BD)//ether type polyol (PTMG) were prepared in this study. This study focused on the effect of polyol type on the properties of WPU. Soft segment Tg (Tgs), 100% elastic modulus and tensile strength were highest when using carbonate polyol, followed by ester polyol and ether polyol, while those of elongation showed the opposite trend. The WPU synthesized with MPD - containing polyol showed lower Tgs, 100% elasticity and strength, and higher elongation than MPD - free WPU. The % transmittance and transparency of the WPU film containing the MPD component was superior to that of the WPU film containing no MPD component, and it was found that the film based on carbonate polyol was slightly better than the film based on ester polyol and ether polyol.