Polyurethaneurea aqueous dispersions prepared with diethyltoluenediamine as chain extender

A series of polyurethaneurea (PUU) aqueous dispersions either with diethyltoluenediamine (DETDA) or ethylenediamine (EDA) as chain extender were prepared with polyester polyol, isophorone diisocyanate and dimethylol propionic acid (DMPA), and characterized. It was found that the physical properties of the PUU aqueous dispersions prepared with DETDA were similar to or better than those prepared with EDA. Compared with the EDA-extended waterborne PUU films, the water resistance and the mechanical properties of the DETDA-extended waterborne PUU films were enhanced appreciably; these enhancements are attributed to the strong hydrogen bonding in urea carbonyl groups and the ordered structure of hard segments in the systems. The DETDA-extended PUU film with 40 wt.% of hard segment and 4.0 wt.% of DMPA unit showed the lowest water-absorbing amount (2.6 wt.%) over all PUU films studied. The hydrophobic surface of the DETDA-extended PUU film modified with a small amount of aminoethylaminopropyl polydimethylsiloxane (AEAPS) was observed and its hydrophobicity was enhanced by increasing the AEAPS content further.     

Investigation of polyurethane (urea)/modified nano-calcium carbonate hybrid aqueous dispersions and their films

This investigation was focused on properties of polyurethane (urea) (PUU) by incorporating silica sol-modified nano-calcium carbonate (CaCO₃). The FT-IR spectroscopy and ζ potential measurement indicated the presence of a hybrid effect due to the hydrogen bonding between the nano particles and the polymer matrix. For these hybrid aqueous dispersions, the particle size decreased as the modified nano-CaCO₃ content increased, and the polydispersity index was very narrow (<1.20). Films prepared with the hybrid PUU aqueous dispersions exhibited excellent waterproof performance: the amount of water absorption was as low as 9.0 wt %, and the contact angle of water on the surface of this kind of film was as high as 93°C. TGA results indicated the high thermal stability of hybrid PUU polymers (223–255°C). The properties like tensile strength, hardness, and elongation at break were influenced by the modified nano-CaCO₃ content in the polymers. The hybrid PUU with 15 wt % modified nano-CaCO₃ content showed the optimum properties. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Preparation and water resistance of crosslinked waterborne polyurethaneurea

Abstract

Two series of cross-linked polyurethaneurea (PUU) aqueous dispersions with polyoxypropylene glycerol and pentaerythritol as internal cross-linking agents were prepared and characterised. The results revealed that in comparison with the uncross-linked one, the cross-linked PUU films exhibited excellent waterproof performance and mechanical properties. The amount of water absorption was as low as 2?5 wt-%, the contact angle of water on the surface of this kind of film was as high as 96°, and the tensile strength was as high as 42?8 MPa. The cross-linked PUU films with polyoxypropylene glycerol and pentaerythritol as cross-linked agents showed different properties at the same cross-linking agent content. The prepared triol-cross-linked or tetra-cross-linked PUUs had great potential application in meeting the highly diversified demands in modern technologies such as coatings, leather finishing, adhesives, sealants, plastic coatings and wood finishes, where high water resistance and durability were required.     

植物油基聚酯酰胺多元醇的合成及其在水性聚氨酯中的应用

以菜籽油和二乙醇胺为原料制备了脂肪醇酰胺混合多元醇RDEA，进一步和己二酸等原料反应合成了系列的聚酯酰胺多元醇，并对两类多元醇进行了表征。以聚酯酰胺多元醇、二羟甲基丙酸、异佛尔酮二异氰酸酯、苯乙烯和丙烯酸丁酯等原料合成了水性聚氨酯脲（PUU）分散液及聚氨酯脲-乙烯基聚合物（PUA）复合水分散液，并对其流变性能及稳定性进行了研究。     

含高相对分子质量氟化聚硅氧烷链段的水性聚氨酯脲的制备与性能(英文)

以数均相对分子质量(n)较高(8 361～21 760)的α,ω-二羟基聚甲基(3,3,3-三氟丙基)硅氧烷(PTFPMS)、聚酯二元醇、二羟甲基丙酸、异佛尔酮二异氰酸酯和乙二胺为原料,制备了一系列贮存稳定性优良的大分子主链中含有少量(质量分数为5%)长PTFPMS链段的聚氨酯脲(PUU)水分散液,并对其性能进行了研究.结果表明,与未改性或用低相对分子质量(n 为798)PTFPMS改性的PUU水分散液相比,用高相对分子质量PTFPMS改性的PUU水分散液的粒径减小;含高相对分子质量PTFPMS链段的PUU水分散液成膜后,其表面疏水性和力学性能比纯PUU水分散液有很大程度的提高,而比含低相对分子质量(n 为798)的PTFPMS链段的PUU水分散液有一定程度的提高.     

Preparation and stability of aqueous acrylic polyol dispersions for two-component waterborne polyurethane

In this study, aqueous acrylic polyol dispersions with high stability for a two-component waterborne polyurethane were prepared. To improve the stability of acrylic dispersions, the influence of the acrylic acid (AA) addition method, neutralization, water addition rate during the dilution process, and dispersion equipment on the stability of the aqueous acrylic polyol dispersion was studied using dynamic light scattering and a thermal storage experiment. The acrylic resins’ structure was examined using Fourier transform infrared spectra, and the water resistance of the resultant films was investigated by electrochemical measurements and a water-swelling experiment. The dispersions prepared by two-step AA addition exhibited better particle size distribution, viscosity, and thermal storage compared with those prepared by one-step AA addition. Furthermore, the acrylic resin prepared by two-step AA addition was observed to possess a higher acid value. The corrosion currents of films based on dispersions prepared by two-step AA addition decreased to a smaller extent after 24 h of immersion in water. The dispersions afforded smaller particles when larger amounts of neutralizer and slower water addition rates were used. The dispersions prepared using a sawtooth disk dispersion machine displayed better performance than that prepared using a homogenizer dispersion machine.     

可再生原料为交联剂制备水性聚氨酯脲

以二苯基甲烷二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)为硬段,聚氧化丙烯二元醇(GE210)为软段,乙二胺(EDA)为扩链剂,制备了具有良好分散性的阴离子水性聚氨酯脲(PUU)分散液。并用可再生的氧化玉米淀粉对其进行了交联改性。测试结果表明,加入氧化交联淀粉后,水性PUU分散液的表面张力增加,成膜后的力学性能得到改善。同时随氧化淀粉用量的增大,水性PUU膜的拉伸强度也逐渐增大。     

Preparation,mechanical properties of waterborne polyurethane and crosslinked polyurethane‐acrylate composite

The waterborne polyurethane (PU) prepolymer was first prepared based on isophorone diisocyanate, polyether polyol (NJ‐210), dimethylol propionic acid (DMPA), and hydroxyethyl methyl acrylate via in situ method. The crosslinked waterborne polyurethane‐acrylate (PUA) dispersions were prepared with the different functional crosslinkers. The chemical structures, optical transparency, and thermal properties of PU and PUA were confirmed by Fourier transform infrared spectrometry, ultraviolet–visible spectrophotometry, and differential scanning calorimetry. Some physical properties of the aqueous dispersions such as viscosity, particle size, and surface tension were measured. Some mechanical performances and solvent resistance of PUA films were systemically investigated. The experimental results showed that the particle sizes of the crosslinked PUA aqueous dispersions were larger than the PU and increased from 57.3 to 254.4 nm. When the ratios of BA/St, BA/TPGDA, and BA/TMPTA were 70/30, PUA films exhibited excellent comprehensive mechanical properties. The tensile strength and elongation at break of the film were 2.17 MPa and 197.19%. When the ratio of BA/St was 30/70, the film had excellent water resistance and was only 6.47%. The obtained PUA composites have great potential application such as coatings, leather finishing, adhesives, sealants, plastic coatings, and wood finishes. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Dynamic colloidal processes in waterborne two-component polyurethanes and their effects on solution and film morphology

While waterborne two-component polyurethanes (WB 2K-PURs) offer an attractive approach toward the reduction of volatile organic compounds (VOC), a number of fundamental processes related to the colloidal stability and solution morphology of WB 2K-PUR reactive dispersions are not understood. These studies focus on mechanisms of inter-particle reactant aggregation in heterogeneous aqueous dispersions resulting from solution morphological changes of poly(ethylene glycol) modified water-dispersible polyisocyanates (WDPI) and water-reducible polyester polyol coreactants, as revealed by particle size measurements and in situ NMR T₂ studies. Based on the results of these experiments, a model of film formation is proposed which relates solution morphological features and chemical reactions. WDPI reactant droplets become hydrated over time, leading to formation of carbon dioxide, which dissolves in the aqueous continuum as carbonic acid and subsequently destabilizes anionically stabilized polyol droplets, resulting in their adsorption to WDPI droplet surfaces. The implications of polyol collapse, as they pertain to film formation, are discussed in the context of solution and film morphologies.     

硅溶胶/苯乙烯-丙烯酸酯共聚物无机-有机杂化水分散液的制备和表征

A stable silica sol with 3-5 nm in diameter, which can form homogeneous film without crack, was prepared and characterized. Then, the inorganic-organic hybrid aqueous dispersion composed of such a silica sol and an emulsion of styrene （St） and acrylate （Ac） copolymer was prepared and the hybrid effect between the silica sol and poly（St-co-Ac） was observed by Fourier transform infra-red （FT-IR） spectroscope. The toughness of the film prepared by this kind of hybrid aqueous dispersion was excellent, as it was enhanced appreciably by commixing with a small amount of poly（St-co-Ac） emulsion. Some amino-polysiloxane modified hybrid aqueous dispersions were also prepared and the properties of the modified dispersions and their films were investigated. The experimental results showed that the film prepared with such an amino-polysiloxane modified hybrid dispersion exhibited excellent hydrophobicity and low surface energy after heat treatment for 1.5 h, during which the formation of the graft copolymer was observed. The surface energy of this film decreases as a result of the enrichment of siloxane segments on the film surface.     

气干型水性聚氨酯的合成与表征

将自制的水性聚酯多元醇、异佛尔酮二异氰酸酯在无有机溶剂参与的情况下进行预缩聚,然后将亚油酸与多羟基化合物三羟甲基丙烷进行酯化反应,获得油脂多元醇混合物。将该油脂多元醇混合物作为干性油脂结构的扩链剂引入到聚氨酯预聚体结构中交联分散于水中,合成了气干型的水性聚氨酯分散液,通过红外光谱(FT-IR)对产物结构进行了表征。采用电子万用试验机和热重分析仪对产物的性能进行测试,结果表明:所制备的气干型聚氨酯胶膜具有良好的力学性能、热稳定性以及耐水性。     

Preparation and characterization of a polydimethylsiloxane‐modified,epoxy‐resin‐based polyol dispersion and its crosslinked films

Waterborne polydimethylsiloxane‐modified epoxy‐resin‐based polyol dispersions were synthesized by the reaction of 2,4‐toluene diisocyanate with 2,2‐bis(hydroxymethyl) propionic acid, hydroxypropyl‐terminated polydimethylsiloxane (HTPDMS), and bisphenol A epoxy resin based polyol. These HTPDMS‐modified polyol dispersions exhibited a small particle size and an excellent dispersion stability. Two‐component waterborne polyurethane (2K‐WPU) was prepared from the HTPDMS‐modified polyol dispersion and a hydrophilic‐modified polyisocyanate. The structure of the HTPDMS‐modified polyol and its crosslinked 2K‐WPU films (SEFs) were characterized with Fourier transform infrared and NMR spectroscopies. The effects of the HTPDMS content on the mechanical and thermal properties of the resulting SEFs were investigated. The results show that the thermal stability of the crosslinked SEFs was enhanced with increasing HTPDMS content, whereas the modulus, tensile strength, and pencil hardness values of the films decreased with increasing HTPDMS content. Siloxane segments migrated onto the surface during the film‐formation process. The contact angle of the films increased from 71 to 96 °, and the water absorption ratio of the films decreased from 6.6 to 5.0% when the HTPDMS content in the films increased from 0 to 10%. These results indicate that the water resistance of the films was enhanced by the introduction of HTPDMS into the 2K‐WPU networks. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44342.     

超支化结构对水性聚氨酯脲分散液性能的影响

通过聚氧化丙烯二元醇(GE220)、二羟甲基丙酸(DMPA)和异佛尔酮二异氰酸酯(IPD I)和端羟基超支化聚酯(HBP)反应合成了聚氨酯(PU)预聚体,然后以乙二胺(EDA)为扩链剂,合成了一系列不同HBP含量的聚氨酯脲(HPUU)水分散液,讨论了HBP用量对其性能的影响。结果表明,与不含HBP的水性PUU分散液相比,引入交联结构后,所有的HPUU水分散液的粒径和表面张力稍有增大,粘度从39.29 mPa.s降到25.73 mPa.s,水分散液的高温和冻融稳定性基本不变。     

Preparation and stability behavior of the colloidal epoxy-1,1-iminodi-2-propanol adducts

Epoxy-amine adduct was prepared by reaction between DGEBA and 1,1-iminodi-2-propanol. The kinetic of the reaction was investigated by differential scanning calorimetry (DSC) and a model-free approach. The epoxy-amine adducts were prepared with various molar ratios of amine functionalities. Waterborne dispersions of these resins have been prepared by neutralization of amine functionalities in the epoxy-amine adducts. Fourier Transform Infrared Spectroscopy (FTIR) and DSC were also used to characterize the prepared epoxy-amine adducts. The stability behavior of the neutralized epoxy-amine adducts has been studied at 25 °C in aqueous solution of acetic acid. In each case, the experimental stability ratios (W) versus electrolyte concentration plots were fitted using the Derjaguin–Landau–Verwey–Overbeek (DLVO) theory and modified Fuch's model. The resulted values of diffuse potentials and Hamaker constants were obtained for the aqueous dispersions of the epoxy-amine adducts. According to the resulted Hamaker values, the applicability of the DLVO theory to the colloidal particles of epoxy amine adducts was investigated. The cathodic electrodeposition behavior of the prepared dispersions were also investigated. It was found that the samples with lower degree of neutralization result in a more efficient film deposition followed by higher dry film thickness although they show lower stability in the electrodeposition bath.     

Synthesis and characterization of crosslinked polyurethane dispersions based on hydroxylated polyesters

Stringent environmental regulation has endowed dispersible coatings with excellent property profiles in industrial applications. In this aspect, aqueous polyurethane dispersions (PUDs) are of special interest. The present study reports on the synthesis of hydroxylated polyester (HP) based polyurethane polyols containing internal carboxyl group with different diisocyanates. These polyurethane polyols were partly acetoacetylated with ethyl acetoacetate to incorporate β‐ketoester in the polyurethane polyol backbone. The synthesized polyols were characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, and differential scanning calorimetry. Polyurethane polyols and their acetoacetylated cousins were used to develop PUDs. Particle size of the reactive PUDs was evaluated by a particle size analyzer. PUDs were crosslinked with hexamethoxy methyl melamine and their film properties were studied by dynamic mechanical and thermal analyzers and thermogravimetric analyses. The effects of different diisocyanate and acetoacetylation on the stability of reactive dispersion and properties of the crosslinked films were evaluated. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 368–380, 2006     

Effect of isocyanate to hydroxyl index on the properties of clear polyurethane films

Clear polyurethane films were made from aqueous polyurethane pre-polymer dispersions and water-dispersible aliphatic isocyanate pre-polymer, varying the amount of isocyanate used to cure the films. Film series were made from one of two polyol dispersions; the control XP-7110 having a higher molecular weight and containing 10 wt.% n-methylpyrrolidone (nmp) was compared to a zero-volatile organic compound (VOC) lower molecular weight alternate polyol XP-2591. Increasing the relative number of isocyanate groups to hydroxyl groups in these films provided an increase in glass transition temperature (T_g), tensile strength, elastic modulus and improved barrier properties to dimethyl methylphosphonate (DMMP) for both polyols in this study. At all indices in this study XP-7110 films achieved slightly higher T_g and slightly better resistance to permeation by DMMP than the XP-2591 films. Water resistance of the films was not improved at higher indices nor was there any difference between the polyols. Yet, the experimental results suggest that it is possible to produce polyurethane binders with acceptable film properties while reducing the VOC content of the formulation by using t-butyl acetate as the isocyanate reducing solvent. The zero-VOC polyol achieved better tensile properties with higher indexing than the current polyol containing 10 wt.% VOC. While the zero-VOC polyol did not perform as well as the baseline polyol in some tests, the differences in performance were small and thus there may be an opportunity to use the zero-VOC polyol as a partial or even a complete replacement of the current material.     

双组分水性聚氨酯胶粘剂的合成与应用

以聚醚多元醇、甲苯二异氰酸酯、二羟甲基丙酸及三乙胺等基本原料制得水性聚氨酯,以聚醚多元醇、甲苯二异氰酸酯和异佛尔酮二异氰酸酯等为原料合成了可水分散异氰酸酯交联剂,对合成过程的某些影响因素进行了讨论。还介绍了这种双组分水性聚氨酯胶粘剂在复合薄膜等领域应用试验情况,该水性胶粘剂具有良好的贮存稳定性,较长的适用期和良好的粘接性能。     

Self-emulsifiable soybean oil phosphate ester polyols for low-VOC corrosion resistant coatings

A series of soybean oil phosphate ester polyols (SOPEP) was prepared by reaction of fully epoxidized soybean oil with phosphoric acid and simultanoeous hydrolysis in the presence of a polar solvent. The polyols were characterized by determination of acid value, oxirane number, hydroxyl value, molecular weight (GPC), and FTIR spectra. These polyols with varying amounts of acid phosphate groups could be self-emulsified to form aqueous dispersions after neutralization with organic base. These aqueous dispersion showed varying degrees of stability and their appearance ranged from opaque dispersions to translucent to clear solutions. Waterborne coating compositions were prepared using these aqueous dispersions as principal components and their thermally cured film properties were studied. it was found that by careful selection and formulation, SOPEPs can be successfully used for low-VOC waterborne coating formulations. SOPEPs with 3.5% phosphate ester content showed visibly superior corrosion resistance properties.     

Effect of cardanol diol on the synthesis,characterization, and film properties of aqueous polyurethane dispersions

This article reports on the effect of a diol prepared from a renewable resource, cardanol, on the synthesis, film formation and film properties of aqueous polyurethane dispersions. The PU dispersions were prepared by the acetone process from poly(tetramethylene ether)glycol (PTMEG) and isophorone diisocyanate (IPDI) prepolymer at constant NCO/OH ratio of 1:1.1. Dispersions with two different concentrations of cardanol diol (OH value 140 mg KOH/g) were prepared through chain extension and characterized for solid content, particle size, and particle-size distribution (PSD). Free films were prepared by casting and were studied for their thermal, mechanical, viscoelastic, and hydrophobic properties. Due to the broad PSD, the dispersions containing cardanol diol exhibit better film formation property in comparison to the butane diol chain-extended PU. Soft and flexible films were obtained using cardanol diol as chain extender, whereas brittle film was obtained with butane diol chain extender. Morphological characterization using atomic force microscopy (AFM) and scanning electron microscopy (SEM) suggests a heterogeneous and amorphous nature of the polyurethanes-containing cardanol diol. The thermomechanical and viscoelastic properties show that incorporation of cardanol diol decreases the glass transition temperature and modulus of the films but enhances the properties like thermal stability, hydrophobicity, elongation, etc., of the polyurethane films.     

水性聚氨酯的制备

要制得性能优良的木器用水性聚氨酯乳液,要从制备水性聚氨酯用的原料聚酯二元醇入手,文章设计分子量为1000的聚酯二元醇,它使用邻苯二甲酸酐和己二酸以摩尔比40∶60混合后再与乙二醇反应,制得的水性聚氨酯乳液,其化学稳定性、涂膜硬度,相对于单独用脂肪族聚酯二元醇制备的水性聚氨酯的性能要优。