Preparation of waterborne polyurethanes using an amphiphilic diol for breathable waterproof textile coatings

The application of polyurethanes (PUs) on breathable waterproof fabric coatings requires a balance of water vapor permeability (WVP) and water resistance which can be achieved by tailoring hydrophilic and hydrophobic segments. PU prepolymers were prepared from isophorone diisocyanate, dimethylol butanoic acid, and a mixture of various ratios of amphiphilic PPG2050 (copolymer of ethylene oxide and propylene oxide with –OH end groups) and hydrophobic poly(tetramethylene ether glycol) (PTMEG). After neutralization with triethylamine, the prepolymers were chain-extended with ethylene diamine/1,4-butanediol (1:1 by molar). The WVP values of the fabric coatings prepared using various waterborne PUs were very similar (910–990 g/m² × 24 h). When waterborne PUs prepared using a mixture of PPG2050 and PTMEG were employed for the textile coatings, the resulting PU-coated textiles exhibited excellent waterproof properties (>10,000 mm H₂O). The textile coatings prepared from PPG2050/PTMEG-based waterborne PUs were significantly more waterproof than those prepared from poly(ethylene glycol) (PEG)/poly(propylene glycol) (PPG)/PTMEG-based waterborne PU. This is probably due to a more even distribution of hydrophobic segments in the PUs, even though the WVP values of the PEG/PPG/PTMEG-based PU coatings were considerably smaller than those of the PPG2050/PTMEG-based PU coatings.     

Effect of polyhydric alcohols on the mechanical and thermal properties,porosities, and air permeabilities of polyurethane-blended films

Polyurethane (PU) and polyhydric alcohols composites were successfully prepared to be used as coating materials for fabrics. The effects of various polyhydric alcohols on the PU composites properties have been investigated. The tensile strengths, glass-transition temperatures, thermal-mechanical properties, and swelling capacities of the PU/polyhydric-alcohol-blended films are described in detail, along with their surface and cross-sectional morphologies. The tensile strengths and glass-transition temperatures of the PU/polyhydric-alcohol-blended films were found to decrease remarkably with increasing polyhydric-alcohol concentration. The swelling capacities and porosities of the PU/poly(propylene glycol) (PPG)-blended and PU/glycerol-blended films were observed to increase with increasing PPG or glycerol concentration. However, the poly(ethylene glycol) (PEG) concentration in the PU/PEG-blended film did not significantly affect its properties. The air and water-vapor permeability of nonwoven nylon fabrics coated with PU/PPG and PU/glycerol increased with increasing PPG or glycerol contents, while those coated with PU/PEG were unaffected by PEG content. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47429.     

Effects on the structure and properties of membranes formed by blending polydimethylsiloxane polyurethane into different soft‐segment waterborne polyurethanes

Polydimethylsiloxane polyurethane (PDMS‐PU), which was synthesized from PDMS as the soft segment, was blended into a variety of ester‐ or ether‐based soft‐segment waterborne polyurethanes with different concentrations to investigate the crystallization, thermal, and physical properties of the membrane formations. According to X‐ray analysis, the ether‐based PUs, synthesized from soft segments of poly(propylene glycol) (PPG1000) or poly(ethylene glycol) (PEG2000), were found to have maximum crystallinity at a 5% blending ratio of PDMS‐PU, but the ester‐based PU, synthesized from soft segments of polycaprolactone (PCL1250), had decreased crystallinity at a 5% blending ratio. Differential scanning calorimetric analysis revealed that the T_g,s values of PUs were highest when the blending ratio of PDMS‐PU was 5%–10%, except for PU from PCL1250. Moreover, ether‐based PUs showed maximum T_m,h values, but the T_m,h of the ester‐based PU was greatly reduced when PU with PCL1250 was blended with PDMS‐PU. In addition, the PU from PEG2000 had the highest melting entropy. Mechanical property analysis showed that the stress of ether‐based PUs would be increased when PUs were blended with a small amount of PDMS‐PU and that the stress of PU from poly(tetramethylene glycol) (PTMG1000) increased to its greatest value (20–30 MPa). On the other hand, the ester‐based PU, from PCL1250 blended with PDMS‐PU, would have reduced stress. On the whole, the stress and strain of PU from PEG1000 had excellent balance. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 210–221, 2006     

Thermal and surface characterization of polyurethane–urea clay nanocomposite coatings

This paper reports synthesis and characterization of polyurethane–urea (PU‐urea) and the nanocomposites derived from the PU‐urea with silicate clays. Organophilic montmorillonite cotreated by cetyl trimethyl ammonium bromide (CTAB) was synthesized and used to prepare PU‐urea/montmorillonite nanocomposites coatings. PU‐ureas were prepared from polyethylene glycol (PEG), polypropylene glycol (PPG), trimethylol propane (TMP), and 4,4′‐diphenylmethane diisocyanate (MDI) by reacting excess diisocyanate with polyether glycols. The excess isocyanate of the prepolymers was cured with atmospheric moisture. The synthesized moisture cured PU‐urea and nanocomposites were characterized by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetric (DSC), and angle resolved X‐ray photoelectron spectroscopy (AR‐XPS). The thermal stability of the PU‐urea nanocomposites was higher relative to the mother PU‐urea films. DSC results showed a slight enhancement in the soft segment glass transition temperature after 3 wt % clay loading. The surface properties showed an enrichment of the soft segment toward the surface. An enhancement in the hard segment composition in the nanocomposite coatings has resulted in enhancing the phase mixing process. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2393–2401, 2006     

Synthesis and biodegradation of copolyesterether of copoly(succinic anhydride/ethylene oxide) with polyether

The thermal properties and biodegradability of block copolyesterethers based on copoly[succinic anhydride (SA)/ethylene oxide (EO)] (polymer composition range SA/EO 42/58–49/51 mol %), synthesized by ring-opening copolymerization and poly(ethylene glycol) (PEG) or poly(propylene glycol) (PPG), were studied. The block copolyesterethers synthesized from higher than 7000 molecular weight (M_n) or high SA content copoly(SA/EO), SA/EO = 48/52 or 49/51, and PEG showed melting points and fusion heats (ΔH) similar to those of the prepolymers without leading to a microphase-separation structure. Enzymatic degradability of the block copolyesterethers synthesized from biodegradable copoly(SA/EO) with a low SA content (SA/EO = 42/58 mol %) and PEG was significantly smaller compared to that of the chain-extended copoly(SA/EO) used as a prepolymer. On the other hand, the block copolymers synthesized by an equimolar amount of copoly(SA/EO) and PPG showed evidence of a microphase-separation structure. An increase in propylene glycol (PG) content interfered with the formation of a microphase-separation structure. However, the block copolyesterethers including nonbiodegradable copoly(SA/EO), with a high SA content (SA/EO = 49/51 mol %), and PPG were found to be enzymatically degradable. In the biodegradation testing with standard activated sludge, the block copolyesterethers were degraded by microorganisms in activated sludge. The relationship between polymer composition and the biodegradation rate by activated sludge shows a similar trend to that of enzymatic hydrolysis. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 2095–2106, 1998     

Synthesis and properties of UV-curable waterborne unsaturated polyester for wood coating

UV-curable waterborne unsaturated polyesters for wood coatings were prepared. The effects of different polyols and acids on the properties of the UV-curable waterborne unsaturated polyesters were investigated. Several different unsaturated polyester prepolymers were prepared from three different polyols [ethylene glycol (EG), diethylene glycol (DEG), and propylene glycol (PG)] and three different acids [tetrahydrophthalic anhydride (THPAn), terephthalic acid (TPA), and trimellic anhydride (TMAn)]. UV-curable coating materials were formulated from the prepolymers and 2-hydroxy-2-methylphenyolpropane-1-one as a photoinitiator with distilled water as a diluent. Trimethylolpropane diallyl ether was used as an air inhibitor of cure. The dynamic mechanical studies showed the properties of those unsaturated polyesters were well correlated with their glass transition temperature behaviors. It was found that the unsaturated polyester prepared with 60/40 (mol %) TMAn/THPAn and the equimolar mixture of EG, DEG, and PG showed balanced coating properties such as good tensile properties and weatherability, as well as proper viscosity (ca. 2500 cps) when using distilled water as a diluent. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 695–708, 1998     

水性聚氨酯/聚甲基丙烯酸甲酯杂化乳液的合成

用异佛尔酮二异氰酸酯(IPDI)、聚丙二醇(PPG)和二羟甲丙酸(DMPA)合成了水性聚氨酯分散体(WPU),讨论了PPG摩尔质量,NCO/OH及PPG/DMPA比例对WPU乳液和涂膜性能的影响。以WPU为种子与甲基丙烯酸甲酯进行乳液聚合制备杂化乳液,研究了不同PU/PMMA物质的量比例对杂化乳液及涂膜性能的影响,并采用TEM对WPU及杂化乳液粒子进行了表征。结果表明,在以PPG1000为原料,NCO与OH物质的量比为1.4∶1,PPG与DMPA物质的量比为1∶0.8条件下制备的WPU杂化乳液,随着PMMA比例增加,杂化乳液的稳定性和成膜性变差,聚合物膜断裂伸长率降低,但铅笔硬度、耐水性及耐乙醇性均得到了改善。     

水性聚氨酯聚丙烯酸酯细乳液的制备及在调湿涂料中的应用

首先以聚氧化丙烯二醇(PPG)、异佛尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)为主要单体,甲基丙烯酸羟乙酯(HEMA)为接枝试剂,合成了接枝聚氨酯预聚体(PU-HEMA),进一步与丙烯酸酯进行共聚反应,制备了水性聚氨酯/聚丙烯酸酯(PU-PA)细乳液。考察了单体用量及PA/PU质量比对乳液性能的影响,发现DMPA、HEMA最佳用量分别为3%和6%。采用FTIR、TG、SEM对PU-PA进行了表征。然后以PU-PA为成膜物,硅藻土、膨润土等为颜填料,所制备的PU-PA调湿涂料(PU-PA-C)性能达到国家内墙涂料和建筑涂料标准,其耐洗刷性大于900次,最大吸水率达到206%。该涂料吸/放湿(水)性能强,可用于室内调湿涂料的涂刷。     

Structure–property relationships of poly(urethane‐urea)s with ultralow monol content poly(propylene glycol) soft segments. III. influence of mixed soft segments of ultralow monol poly(propylene glycol), poly(tetramethylene ether glycol), and tri(propylene glycol)

Recent advances in the catalyst technology associated with the production of poly(propylene glycol) (PPG) have allowed for the fabrication of ultralow monol content PPG macrodiols (Acclaim? polyols), which are highly bifunctional and can be produced in substantially higher molecular weights and with narrower molecular weight distributions than previously possible. These factors have enabled the preparation of higher value elastomers and may allow for the first manufacture of economically attractive PPG‐based poly(urethane‐urea) (PUU) fibers. In the past, many performance polyurethane and PUU elastomers used poly(tetramethylene ether glycol) (PTMEG) for the soft segments either alone or in combination with other macrodiols. The work presented here details the investigation of the morphological features of PUU systems with mixed soft segments of PPG, PTMEG, and a low molecular analog of PPG, tri(propylene glycol) (TPG) in an effort to ascertain the influence of structural features on the mechanical and thermal properties of the elastomers. Also of interest was whether the incorporation of PPG and TPG would either prohibit or greatly hinder the formation of strain‐induced PTMEG crystallites. It was found that, even when only 60 wt % of the soft segments consisted of PTMEG, those soft segments were still able to undergo recognizable strain‐induced crystallization as detected by wide‐angle X‐ray scattering. It was also seen that, as the ratio of PPG to PTMEG was varied, there were systematic changes in the soft segment glass transition and cold crystallization characteristics. Inclusion of PPG and TPG resulted in PTMEG's diminished ability to undergo cold and strain‐induced crystallization, as seen with differential scanning calorimetry and wide‐angle X‐ray scattering. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3520–3529, 2003     

Pressure-volume-temperature properties for binary and ternary polymer solutions of poly(ethylene glycol), poly(propylene glycol), and poly(ethylene glycol methyl ether) with anisole

Pressure-volume-temperature properties were measured for polymer solutions of poly(propylene glycol) (PPG)+anisole, polymer blends of PPG+poly(ethylene glycol methyl ether) (PEGME), and the blends of PPG+PEGME and poly(ethylene glycol) (PEG)+PPG with anisole at temperatures from 298.15 to 348.15 K and pressures up to 50 MPa. The Tait equation represents accurately the pressure effect on the liquid densities over the entire pressure range. The excess volumes change from positive to negative as increasing the mole fraction of PPG in the binary systems of PPG+anisole and PPG+PEGME. The volumetric data of the related binary systems were correlated with the Flory-Orwoll-Vrij and the Schotte equations of state to determine the binary parameters. By using these determined binary parameters, both equations predicted the specific volumes of the polymer blends with anisole to average absolute deviations of better than 0.13%.     

Green polyurethane from dimer acid based polyether polyols: Synthesis and characterization

In this study, dimer acid (DA) obtained from waste soybean oil was used together with propylene oxide (PO) to obtain novel polyether polyols [prepolymers for polyurethanes (PUs)] through ring‐opening polymerization reaction. The average molecular weight of polyols was estimated by gel permeation chromatography and titration method. The substantial reaction between DA and PO was evident from FTIR and nuclear magnetic resonance spectroscopy. Subsequently, the polyols were reacted with chain extender [ethylene glycol, (EG)] and 4, 4 ‐ Diphenylmethane diisocyanate (MDI) to prepare green PUs. The effect of molar ratio variation of EG and MDI with a fixed amount of polyols was estimated by measuring hydrophobicity and mechanical strength of PUs. The molar ratio such as 1 : 4 : 5.7 of polyol : EG : MDI was found to exhibit maximum hydrophobicity and improved mechanical strength that were comparable with typical PU sample prepared from commercially available polyol, such as polypropylene glycol. FTIR spectroscopic analysis confirmed the chemical changes and possible crosslinking in PUs. Thermalgravimetric analysis and differential scanning calorimetry analysis also showed substantial thermal stability of the green PUs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41410.     

Synthesis and characterisation of polyurethanes derived from waste black liquor lignin

Waste black liquor lignin, obtained from bagasse from the small-scale paper industry, can be utilized for the synthesis of polyurethanes (PUs). Several polyurethane samples were prepared from laboratory black liquor (LBL) by reacting varying amounts of lignin ranging from 5 to 70% (w/v) in poly(ethylene glycol) (PEG) (having molecular weights of 200, 600, 1000, 1500 and 4000) with tolylene 2,4-diisocyanate (TDI). The effects of lignin concentration and molecular weight of PEG on mechanical and thermal properties of PUs obtained were investigated. The polyurethanes synthesised were characterized for different properties such as shear strength, adhesion and thermal stability. The shear strength of PU joints with aluminum was found to decrease with increase in both lignin concentration and molecular weight of PEG. Maximum shear strength, i.e. 3.6 N/mm², was shown by 50% (w/v) lignin in PEG of molecular weight 200.     

Microwave dielectric relaxation and molecular dynamics in binary mixtures of poly(propylene glycol) 2000 and poly(ethylene glycol)s of varying molecular weight in dilute solution

Molecular dynamics of binary mixtures of poly(propylene glycol) (PPG) and poly(ethylene glycol)s (PEGs) of varying molecular weight due to molecular interactions, chain coiling and elongation in dilute solution under various conditions, ie varying number of monomer units of PEG, method of mixing of polymers and solvent environment, has been explored using microwave dielectric relaxation times. The average relaxation time τ_o, relaxation time corresponding to segmental motion τ₁ and group rotations τ₂, of a series of binary mixtures of poly(propylene glycol) 2000 and poly(ethylene glycol) of varying molecular weight (ie PPG 2000 + PEG 200, PPG 2000 + PEG 300, PPG 2000 + PEG 400, and PPG 2000 + PEG 600 mixed by equal volume in the pure liquid states, and PPG 2000 + PEG 1500, PPG 2000 + PEG 4000 and PPG 2000 + PEG 6000 mixed equal weights in solvent) have been determined in dilute solution in benzene and carbon tetrachloride at 10.10 GHz and 35 °C. A comparison of the results of these binary systems of highly associating molecules shows that the molecular dynamics corresponding to rotation of a molecule as a whole and segmental motion in dilute solutions are governed by the solvent density when the solutes are mixed in their pure liquid state. Furthermore, the molecular motion is independent of solvent environment when the polymers are added separately in the solvent for the preparation of binary mixtures. It has also been observed that there is a systematic elongation of the dynamic network of the species formed during mixing of pure liquid polymers in lighter environment of solvent with increasing PEG monomer units, while the elongation behaviour of the same species in the heavier environment of carbon tetrachloride solvent is in contrast to the elongation behaviour of the polymeric species formed in pure PEG. The role of rotating methyl side‐groups in the PPG molecular chain has been discussed in term of the breaking and reforming of hydrogen bonds in complex polymeric species for the segmental motion. In all these mixtures, the relaxation time corresponding to group rotations is independent of the solvent environment and constituents of the binary mixtures. The effect of chain flexibility and coiling in these binary mixtures is discussed by comparing the relaxation times of the mixtures with their individual relaxation times in dilute solutions measured earlier in this laboratory. © 2001 Society of Chemical Industry     

NMR spectroscopy as basis for characterization of Pluronic® F108 and its derivatives

The hydroxyl end groups of Pluronic®F108 {a triblock copolymer surfactant of poly(ethylene glycol) and poly(propylene glycol) [PEG‐PPG‐PEG]} were modified into primary amine, sulfonic acid, and quaternary ammonium equivalents for use in affinity chromatography. NMR was used for monitoring the efficacy of modifications on intermediaries and final products. The primary amine equivalents were prepared via conversion of the hydroxyl groups to a tosylate, its displacement with an azide, followed by reduction to the primary amine. The sulfonic acid equivalents were prepared via hydroxyl group tosylation, the displacement of tosylate with thiol, and its oxidation to sulfonic acid. The conversion to trimethyl ammonium was achieved via hydroxyl group tosylation, tosylate displacement by halide, and halide displacement with trimethylamine. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 109–117, 2000     

The role of the ratio (PEG:PPG) of a triblock copolymer (PPG‐b‐PEG‐b‐PPG) in the cure kinetics,miscibility and thermal and mechanical properties in an epoxy matrix

The aim of this study was to evaluate the role of different poly(ethylene glycol):poly(propylene glycol) (PEG:PPG) molar ratios in a triblock copolymer in the cure kinetics, miscibility and thermal and mechanical properties in an epoxy matrix. The poly(propylene glycol)‐block‐poly(ethylene glycol)‐block‐poly(propylene glycol) (PPG‐b‐PEG‐b‐PPG) triblock copolymers used had two different molecular masses: 3300 and 2000 g mol^?1. The mass concentration of PEG in the copolymer structure played a key role in the miscibility and cure kinetics of the blend as well as in the thermal–mechanical properties. Phase separation was observed only for blends formed with the 3300 g mol^?1 triblock copolymer at 20 wt%. Concerning thermal properties, the miscibility of the copolymer in the epoxy matrix reduced the T_g value by 13 °C, although a 62% increase in fracture toughness (K_IC) was observed. After the addition of PPG‐b‐PEG‐b‐PPG with 3300 g mol^?1 there was a reduction in the modulus of elasticity by 8% compared to the neat matrix; no significant changes were observed in T_g values for the immiscible system. The use of PPG‐b‐PEG‐b‐PPG with 2000 g mol^?1 reduced the modulus of elasticity by approximately 47% and increased toughness (K_IC) up to 43%. Finally, for the curing kinetics of all materials, the incorporation of the triblock copolymer PPG‐b‐PEG‐b‐PPG delayed the cure reaction of the DGEBA/DDM (DGEBA, diglycidyl ether of bisphenol A; DDM, Q3‐4,4′‐Diaminodiphenylmethane) system when there is miscibility and accelerated the cure reaction when it is immiscible. All experimental curing reactions could be fitted to the Kamal autocatalytic model presenting an excellent agreement with experimental data. This model was able to capture some interesting features of the addition of triblock copolymers in an epoxy resin. © 2018 Society of Chemical Industry     

脂肪族聚醚型聚氨酯弹性体热降解机理及热稳定性

采用酯交换缩聚法,以聚四氢呋喃醚二醇（PTMEG）和1,6-六亚甲基二氨基甲酸甲酯（HDU）为原料,以1,4-丁二醇（BDO）为扩链剂,以二丁基氧化锡为催化剂制备脂肪族聚醚型聚氨酯（PU）弹性体。用TGA和FTIR考察聚氨酯弹性体的热降解机理及原料组成对聚氨酯热降解过程的影响。结果表明：聚氨酯弹性体的热降解过程包括两个阶段,分别为硬段（氨基甲酸酯）和软段（聚醚多元醇）的降解,其中硬段（氨基甲酸酯）的降解主要降解产物为碳化二亚胺、CO₂、四氢呋喃及水,软段（聚醚多元醇）的降解主要产物为四氢呋喃和水。随着硬段含量的降低,聚氨酯弹性体初始热降解温度由282℃上升至327℃,聚氨酯弹性体的热稳定性升高。     

Improvement of polyurethane adhesion to glass using novolac primer

The adhesion of polyurethane (PU) coatings based on toluene diisocyanate, poly(propylene glycol) (PPG) 2000, polyethylene adipate (PEA) 2000 and castor oil (CO) was studied. The coatings were applied to glass slides with and without novolac primer (due to the high functionality of castor oil, the resultant PU coatings have limited shelf life). Our studies showed that satisfactory adhesion strengths were achievable for immediate bonding. Furthermore, our study also found that the adhesion of polyurethane to glass surfaces was increased by using a thin layer of novolac primer.     

Effect of pyridazine content and crosslinker structure on the properties of polyurethane elastomers

This article studies the development of a series of heterocyclic polyurethanes (PUs) with various pyridazine content and different crosslinker structure in their main chains. All of the isocyanate‐terminated PU prepolymers were prepared from poly(tetramethylene oxide) glycol of molecular weight 1400 (Terathane 1400) and 1,6‐hexamethylene diisocyanate. The properties of the obtained linear and crosslinked pyridazine‐based PU were compared with the properties of common PUs obtained by chain extension with 1,4‐butanediol. All the obtained PUs were characterized through spectral and thermal behavior. The pyridazine‐based PU showed improved thermal stability with 10% weight loss at temperatures above 370–400°C. With the increase of pyridazine content the values of Young's modulus are higher and the strain at break decreases. Increasing pyridazine content leads to increased films surface hydrophilicity. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Polyurethanes from 4,4′‐diphenylmethane diisocyanate and poly(ethylene glycol)s. II. Crystallographic data,heats of melting and crystallization,thermal stability,crystallinity and density

Wide‐angle X‐ray scattering analysis, heats of melting, crystallization and re‐melting, thermogravimetric analysis and density measurements have been used to study the crystallographic data and degree of crystallinity of linear polyurethanes (PUs) prepared by the polymerization of 4,4′‐diphenylmethane diisocyanate (MDI) with poly(ethylene glycol)s (PEGs) of various number‐average molecular weights (M_ns) (106, 200, 400, 1000, 2000 and 4000 g mol^?1) in equivalent molar ratios. The crystallinities of polyurethanes PU1000 to PU4000 are shown to be due to the polyoxyethylene segments of the PEGs, while PU400 and PU200 appeared to be amorphous. However, PU106, similarly prepared from diethylene glycol (PEG106), is highly crystalline with a different crystal structure. Thermogravimetric analysis of PU106, PU400 and PU1000 exhibited high thermal stabilities up to 260 °C for these materials under the conditions of measurement (10 °C min^?1). The heat of melting for the 100 % crystalline structure of PU106 has been indirectly obtained. Copyright © 2004 Society of Chemical Industry     

Synthesis and properties of highly hydrophilic waterborne polyurethane‐ureas containing various hardener content for waterproof breathable fabrics

As part of an ongoing search for highly hydrophilic waterborne polyurethanes for waterproof breathable fabrics, a waterborne polyurethane [waterborne polyurethane‐ureas (WBPU): P70, the number indicates the poly(ethylene glycol) (PEG) content] dispersion was synthesized from PEG (70 wt %) and dimethylol propionic acid (14 mol %) as the hydrophilic/ionic components, 4,4′‐diisocyanato dicyclohexylmethane as a diisocyanate, ethylenediamine as a chain extender, and aliphatic tri‐isocyanate as a hardener. To determine the best highly hydrophilic WBPU coatings for waterproof breathable fabrics, this study focused on the effect of the hardener content(0–1.2 wt %) in the WBPU P70 sample on the dynamic thermal mechanical properties, contact angle/surface energy, water swelling, water insolubility, and water vapor transmission rate (WVTR). The contact angle, water swelling, glass transition temperature, modulus, and strength increased with increasing hardener content, whereas the surface energy, water insolubility, and WVTR decreased. Sample P70/0.5 (cured sample containing 0.5 wt % of hardener) showed relatively good dimensional stability in water (high water insolubility), strong hydrophilicity (low‐water contact angle/high‐surface energy/high water absorption), and a high WVTR, highlighting its promising applications in waterproof breathable fabrics. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013