• Fibers and Polymers
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• v.2 no.3
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• pp.122-128
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• 2001

UV-curable polyurethane acrylate prepolymers were prepared from diisocyanates [isophorone diisocyanate (IPDI), 2,4-toluene diisocyanate (TDI), or 4,4'-dicyclohexylmethane diisocyanate (H$_{12}$MDI)], diols [ethylene glycol (EG), 1,4-butane diol (BD), or 1,6-hexane diol (HD)], polypropylene glycol as a polyol. UY-curable mixtures were formulated from the prepolymer (90 wt%), reactive diluent monomer trimethylol propane triacrylate (10 wt%). and photoinitiator 1-hydroxycy-clohexyl ketone (3 wt% based on prepolymer/diluent). The effects of different diisocyanates/low molecular weigh dial on the dynamic mechanical thermal properties and elastic recovery of UV-cured polyurethane acrylate films were examined. The tensile storage modulus increased a little in the order of EG > BD > HD at the same diisocyanate. Two loss modulus peaks for all samples are observed owing to the glads transition of softs segments ($T_gh$) and the glass transition temperature of hard segments ($T_gh$). For the same diisocyanate, $T_gh$, decreased, however, $T_gh$ increased, in the order of HD > BD > EG. The elastic recovery also increased in the order of HD > BD > EG at the same diisocyanate. In case of same diols, $T_gh$ increased in the order of $H_12$MDl > TDI > IPDI significantly. The ultimate elongation and elastic recovery increased in the order of TDI > IPDI > $H_12$MDl at the same diol.l.

• Proceedings of the Korean Fiber Society Conference
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• 1996.10a
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• pp.465-467
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• 1996

A series of thermoplastic polyurethane copolymers were prepared from polypropyleneglycol(PPG, MW 3000), 1,4-butanediol, Isophorone diisocyanate(IPDI) and dibutyltin dilaurate(BBT) as catalyst. Studies have been made on the effects of molar ratio of isocyanate /polyol/chain extender on the properties such as tensile and thermal properties. By varying the ration of hard to soft segments, TPU ranging from soft elastomeric polymer to relatively hard elastoplastics and be obtained. The storage modulus and glass transition temperature of TPU increased with increasing the hard segment content.

• Polymer(Korea)
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• v.37 no.2
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• pp.232-239
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• 2013

A series of novel imidazole-blocked diisocyanate bioadhesives (IBAs) were synthesized from reaction of toluene 2, 4-diisocyanate (TDI), isophorone diisocyanate (IPDI), hydroxyl-terminated polylactide (HO-PLA-OH), 1,1,1-trimethylolpropane (TMP), and imidazole. Synthesis of IBAs was confirmed by Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). Differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) revealed that the TDI-based IBA had lower thermal dissociation temperature and a faster deblocking rate than IBA based on IPDI. Hydroxyl-terminated polyurethane (HPU) was introduced to study the adhesive effect of the synthesized IBAs. Improvement on elastic modulus, tensile strength and water resistance of IBA-modified HPU in comparison with neat HPU suggested the good adhesive effect of IBA due to the strong chemical reaction between released NCO groups from IBA and hydroxyl groups from HPU.

• Applied Chemistry for Engineering
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• v.21 no.1
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• pp.46-51
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• 2010

Polyorganosiloxane modified polyurethane (PDMS-PU) polymers were prepared from copolymerization of ${\alpha}$,${\omega}$-hydroxypropyl terminated polyorganosiloxane with isophorone diisocyanate (IPDI), polypropylene glycol (PPG), and 2,2-bis(hydroxymethyl) propionic acid (DMPA). Hydrophobic polyorganosiloxane was introduced in polyurethane main chain as soft segment block unit. The isocyanate groups in PDMS-PU block copolymer was blocked with 2-butanon oxime and obtained PDMS-PU dispersions in water by neutralizing with triethylamine (TEA). The deblocking temperature of PDMS-PU polymer was measured from thermal analysis. The good stability of the PDMS-PU dispersion was obtained by dispersing into water. PDMS-PU prepolymers were prepared with various contents of DMPA under [NCO]/[OH] = 1.12~1.53 equivalent ratio. Increasing DMPA from 7.2, 13.4, and 18.7 mole% in preparation of PDMS-PU polymer, particle sizes were decreased from 156, 100, 65 dnm. Also contact angle and adhesive strength were measured.

• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.632-638
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• 2012

Waterborne polyurethane dispersions (PUD) were synthesized from isophorone diisocyanate (IPDI), polycarbonate diol (PCD) and dimethylol propionic acid (DMPA) as starting materials. Subsequently, waterborne polyurethane-acrylic hybrid solutions were prepared by reacting the PUD with different amounts of the mixture of acrylate monomers, HEMA (2-hydroxyethyl methacrylate) and MMA (methyl methacrylate). As a result, the average particle size of waterborne polyurethane-acrylic hybrid solutions was increased with increasing the addition amounts of acrylate monomers. Also, the prepared coating films from waterborne polyurethane-acrylic hybrid solutions showed better abrasion resistance and chemical resistance than those of pure PUD.

• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.639-645
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• 2012

Waterborne polyurethane dispersion (PUD) was synthesized by capping the NCO groups of polyurethane prepolymers, prepared from isophorone diisocyanate, polycarbonate diol and dimethylol propionic acid, with aminopropyl triethoxysilane (APS). Subsequently, silylated acrylic polyurethane dispersion was synthesized by reacting the PUD with the mixture of acrylate monomers, 2-hydroxyethyl methacrylate and methyl methacrylate. The average particle size of silylated acrylic polyurethane dispersion, measured by the dynamic light scattering method, was increased from 39.0 nm to 399.8 nm by increasing the addition amounts of APS. Also, the pencil hardness of coating films of silylated acrylic polyurethane dispersion was enhanced from B grade to F grade with increasing APS content.

• Korean Chemical Engineering Research
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• v.49 no.3
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• pp.285-291
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• 2011

NCO terminated polyurethane prepolymers were synthesized from isophorone diisocyanate(IPDI), poly (tetramethylene glycol)(PTMG) and dimethylol propionic acid(DMPA). Subsequently, waterborne polyurethanes were prepared by capping the NCO groups of polyurethane prepolymers with different types of silane coupling agents, such as methyltrimethoxysilane(MTMS), glycidoxypropyl trimethoxysilane(GPTMS), methacryloxypropyl trimethoxysilane (MPTMS) and aminopropyl triethoxysilane(APS). The average particle size of the waterborne polyurethane solutions was increased by adding silane coupling agents. Also, the coating films prepared from GPTMS, MPTMS and APS, exhibited better pencil hardness than those from pure waterborne polyurethane. On the other hand, the coating films from MTMS did not show an improved pencil hardness than those from pure waterborne polyurethane.

• Korean Chemical Engineering Research
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• v.49 no.5
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• pp.548-553
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• 2011

NCO terminated polyurethane prepolymers were synthesized from isophorone diisocyanate(IPDI), polycarbonate diol(PCD) and dimethylol propionic acid(DMPA). Subsequently, acrylic terminated polyurethanes were prepared by capping the NCO groups of polyurethane prepolymers with different types of acrylate monomers, such as 2-hydroxyethyl methacrylate(HEMA), 2-hydroxyethyl acrylate(HEA) and pentaerythritol triacrylate(PETA). The average particle sizes of the acrylic terminated polyurethane solutions were increased by capping acrylate monomers. Also, the prepared coating films showed better abrasion resistance and pencil hardness than those of pure waterborne polyurethanes. The coating film with PETA exhibited the best abrasion resistance and pencil hardness of coating films prepared with three acrylate monomers.

• Korean Chemical Engineering Research
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• v.51 no.1
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• pp.73-79
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• 2013

Waterborne polyurethane dispersion (WPUD) was synthesized from polycarbonate diol (PCD), isophorone diisocyanate (IPDI) and dimethylol propionic acid (DMPA) as starting materials. Then, waterborne acrylic polyurethane dispersion (AUD) was synthesized by reacting the WPUD with an acrylate monomer, methyl methacrylate (MMA). Subsequently, the AUD was mixed with multi-walled carbon nanotube (MWCNT) to yield a conductive coating solution, and the mixture was coated on the polycarbonate substrate. With increasing the amount of MMA in the AUD, the pencil hardness, abrasion resistance and chemical resistance of the coating films were improved, but the electrical conductivity of the coating films was decreased. On the other hand, the pencil hardness, abrasion resistance and chemical resistance of coating films were decreased, but the electrical conductivity was enhanced with increasing the amount of MWCNT in the conductive coating solutions.

• Polymer(Korea)
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• v.30 no.5
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• pp.437-444
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• 2006

Reactive hydroxypropyl methylcellulose phthalate (reactive HPMCP) was synthesized by using a stepwise urethane reaction with isophorone diisocyanate (IPDI) and 2-hydroxyethyl moth acrylate (HEMA). Molecular weight, acid number, and critical micelle concentration (CMC) of the synthesized reactive HPMCP and pristine HPMCP were measured and used as a polymeric surfactant in the emulsion polymerizations of styrene. In the preparation of HPMCP-hybrid poly styrene nanoparticles, 6, 9, 12, 18, and 24 wt% of HPMCPs were introduced, and the maximum rate of polymerization ($R_{p,max}$), the average number of radicals per particle (n), particle size distribution were investigated. In addition, core - shell morphology of the nanoparticles were observed by using TEM and their thermal stabilities were measured by using TGA. Reactive HPMCP showed higher $R_{p,max}$, smaller particle size, larger values of n and gel contents as compared with pristine HPMCP, due to the vinyl groups from HEMA, which can be reacted with styrene oligomers, in the reactive HPMCP.