Preparation and properties of UV‐curable waterborne polyurethane–acrylate emulsion

Polyurethane–acrylate oligomer terminated with multiple unsaturated bonds was prepared using isophorone diisocyanate, (IPDI), methylene diphenyl diisocyanate, and polyols as monomers, using 2,2‐dimethylol propionic acid as hydrophilic chain extender, together with pentaerythritol triacrylate (PETA) as end‐capper. The UV‐curable waterborne polyurethane–acrylate (UV‐WPUA) composite emulsion was obtained by mixing the PUA oligomer with certain content of reactive diluents and then dispersing the mixture in water. The molecular structure of the polyurethane prepolymer, PUA oligomer, and UV‐cured polymer was investigated by Fourier transform infrared spectroscopy. The influence of the composition and content of the diluents and end‐capper on UV‐WPUA properties, including the emulsion stability, thermal property, water resistance, adhesion, hardness, glossiness of polymer film were studied. The results show that the WPUA emulsion has excellent stability, and the UV‐cured film features good hardness and remarkable water resistance when PETA is used as end‐capper and the end‐capping ratio of the polyurethane prepolymer is 70% and dipentaerythritol hexaacylate/dipropylene glycol diacrylate (mass ratio 1:1) is used as diluent. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45208.     

Preparation and properties of emulsifier/N‐methylpyrrolidone‐free crosslinkable waterborne polyurethane–acrylate emulsions for footwear adhesives. I. Effect of the acrylic monomer content

Stable emulsions of emulsifier/N‐methylpyrrolidone‐free crosslinkable waterborne polyurethane–acrylates (C‐WBPUAs) with various acrylic monomer contents (0, 10, 20, and 30 wt %) for footwear adhesive materials were successfully prepared in this study. The effects of the acrylic monomer content on the shelf stability, mean particle size, and viscosity of the C‐WBPUA emulsions; the tensile properties and dynamic mechanical thermal properties of the C‐WBPUA film samples; and the adhesive strengths between the upper (synthetic leather) and the sole (ethylene vinyl acetate rubber) in both the dry and wet states of the formulated adhesives (C‐WBPUA emulsion–thickener–hardener) were examined. The adhesive strengths of the formulated adhesives for footwear (leather–sole) in both the dry and wet states increased with increasing acrylic monomer content up to 20 wt %; after this, they almost levelled off. Thus, C‐WBPUA20 and C‐WBPUA30, where the number indicates the acrylic monomer content, can be recommended as high‐performance adhesive materials for footwear. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43758.     

Preparation and properties of waterborne polyurethane‐urea/sodium alginate blends for high water vapor permeable coating materials

To improve the water vapor permeability of coating materials, aqueous sodium alginate (SA) solution was blended with waterborne polyurethane‐urea (WBPU) dispersions synthesized by prepolymer mixing process. The content of SA for stable WBPU/SA dispersions was found to be below 30 wt %. As the SA content increased, the number and density of total micropores (tunnel‐like micropores/isolated micropores) formed after dissolution of SA in water increased, and the water vapor permeability of coated Nylon fabric also increased remarkably. These results clearly demonstrate that utilizing WBPU/water soluble polymer SA blends as coating materials and then dissolving SA in water surely facilitate obtaining prominent breathable fabrics. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Preparation,morphology, and properties of polyurethane–urea elastomers derived from sulphone‐containing aromatic diamine

An aromatic diamine containing both sulfone and diphenyl ether groups, bis[4‐(4‐aminophenoxy)phenyl]sulfone, was synthesized in a two‐step way, whose structure was confirmed through Fourier transform infrared spectrometry, nuclear magnetic resonance, and elemental analysis. Then, the obtained BAPS was used as the chain‐extender to prepare a polyurethane–urea elastomer, whose morphology, thermal stability and mechanical properties were examined by means of attenuated total reflection, DSC, thermogravimetric analysis, dynamic mechanical thermal analysis, and stress–strain measurements. The results showed that the PUU elastomer based on BAPS showed good heat‐resistance and mechanical properties. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3554–3561, 2007     

Synthesis and properties of self‐crosslinkable polyurethane–urea with silsesquioxane formation

Based on the typical two‐step polyurethane–urea synthesis, a new series of self‐crosslinkable polyurethane (PU)–urea formulations, consisting of poly(tetramethylene oxide) and 4,4′‐diphenyl methane diisocyanate, and extended by ethylenediamine (EDA)/aminoethylaminopropyltrimethyoxysilane (AEAPS), were prepared. FTIR, ESCA, WAXD, DSC, and mechanical properties of samples were recorded. The results show that the self‐crosslinkable polyurethane–urea could be crosslinked by hydrolysis of the trimethyloxysiloxane group to form the silsesquioxane structure. These structures represent a kind of nanosize, cagelike, chemical crosslink site as well as filler, which affect the properties of PU. The morphology, varied with different ratios of EDA/AEAPS, was also discussed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 190–195, 2004     

Rigid polyurethane–clay nanocomposite foams: Preparation and properties

Rigid polyurethane–clay nanocomposite foams considered in this work are made with different clay types and for different clay concentrations. The densities of the foams are in the range of 140–160 kg/m³ with possible application as structural materials and for underwater buoyancy‐related uses. Wide‐angle X‐ray diffraction and transmission electron microscopy studies confirm the formation of nanocomposites. The compressive modulus and the storage modulus of the foams increase and the mean cell size decreases with addition of clay. However, the hydraulic resistance of the nanocomposite foams, a measure of the strength of the foam lamellae, is lower than that of the foams without clay. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2802–2809, 2007     

Synthesis and characterization of UV-curable waterborne polyurethane–acrylate ionomers for coatings

A new kind of ultraviolet (UV)-curable waterborne polyurethane–acrylate (PUA) ionomer, prepared from toluene diisocyanate (TDI), polyethylene glycol (PEG), dimethylolpropionic acid (DMPA), triethylamine (TEA), and 2-hydroxyethyl methacrylate (HEMA), was synthesized by the modified prepolymer mixing process in which water serves as a chain-extender and dispersant. Fourier transform infrared (FTIR) spectra demonstrated the formation of the PUA ionomers both in dispersions and in their corresponding cured films. Surface tension of the PUA dispersions decreased as the DMPA-to-PEG mole ratio increased. The investigation of rheological behavior of the PUA dispersions suggested that all the dispersions belong to pseudoplastic fluid and display the characteristic of common polymer dispersions. Differential scanning calorimetry (DSC) analysis showed that the increasing DMPA-to-PEG mole ratio may result in a higher T_g and a broader transition zone for the hard segment. The results of TGA for the PUA-cured films indicated good thermal stability with no appreciable weight loss until well above 200°C. Measurement of physical properties showed that all the PUA-cured films exhibited excellent adhesion, gloss, flexibility, and impact strength, as well as pendulum hardness, depending upon hard segment content. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 2869–2876, 1999     

Synthesis and characterization of waterborne polyurethane adhesives containing different amount of ionic groups (I)

A series of waterborne polyurethanes (WBPU) containing different amount of 2,2‐bis(hydroxymethyl) propionic acid (DMPA) were synthesized using prepolymer mixing process. Relationships between the DMPA content and physical, mechanical, and thermal properties as well as adhesive behavior at different condition were investigated. Stable aqueous dispersions of WBPU were obtained when the DMPA content was more than 10 mol %. At higher DMPA content, the particle size of the WBPU dispersion was lower but the viscosity of the dispersion was higher. Water swelling and tensile strength of the films increased with increasing of DMPA content. The optimum adhesive strength of WBPU adhesives was found to be depended on the DMPA content, pressing temperature, and pressure on adhesion process. The adhesive strength of WBPU adhesives increased with increasing DMPA content. The optimum pressing temperature decreased with increasing DMPA content. The adhesive strength of WBPU adhesives increased with increasing pressure up to 15 kg f/cm² and then leveled off. The optimum pressing temperature of WBPU adhesives samples containing 24.02, 22.05, and 17.05 mol % DMPA was about 100, 120, and 140°C, respectively. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5684–5691, 2006     

Synthesis and thermal properties of polyurethane–polysiloxane crosslinked polymer networks

Polysiloxane–polyurethane crosslinked polymer networks (PSI–PU) were synthesized in solution by polymerization of oligosiloxanes containing γ‐hydroxy propyl groups with polymethane polyphenyl polyisocyanate. Polyether‐based polyurethane and polyester‐based polyurethane were also prepared by a “one‐shot” method. Their thermal properties were studied by thermogravimetric analysis. It was observed that the thermal stability of PSI–PU was better than that of polyether‐based polyurethane and polyester‐based polyurethane, and an inert atmosphere had no effect on decomposition of polyurethanes below 350°C. It was found that polyurethane–polysiloxane crosslinked polymer networks decomposed slower in oxygen than in nitrogen in the temperature range of 350–550°C. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 310–315, 2003     

Carbon nanotubes‐filled thermoplastic polyurethane–urea and carboxylated acrylonitrile butadiene rubber blend nanocomposites

This article reports the preparation and characterization of multiwalled carbon nanotubes (MWCNTs)‐filled thermoplastic polyurethane–urea (TPUU) and carboxylated acrylonitrile butadiene rubber (XNBR) blend nanocomposites. The dispersion of the MWCNTs was carried out using a laboratory two roll mill. Three different loadings, that is, 1, 3, and 5 wt % of the MWCNTs were used. The electron microscopy image analysis proves that the MWCNTs are evenly dispersed along the shear flow direction. Through incorporation of the nanotubes in the blend, the tensile modulus was increased from 9.90 ± 0.5 to 45.30 ± 0.3 MPa, and the tensile strength at break was increased from 25.4 ± 2.5 to 33.0 ± 1.5 MPa. The wide angle X‐ray scattering result showed that the TPUU:XNBR blends were arranged in layered structures. These structures are formed through chemical reactions of ? NH group from urethane and urea with the carboxylic group on XNBR. Furthermore, even at a very low loading, the high degree of nanotubes dispersion results in a significant increase in the electrical percolation threshold. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40341.     

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     

支化型水性聚氨酯胶黏剂的合成及性能

采用异佛尔酮二异氰酸酯(IPDI)、聚四氢呋喃醚二醇2000(PTMG2000)为原料,二月桂酸二丁基锡、1,4-丁二醇和2,2-二羟甲基丙酸分别为催化剂、小分子扩链剂和亲水单体,制得水性聚氨酯预聚体(PPU);接着以丙烯酸甲酯、二乙醇胺和三羟甲基丙烷为原料合成了超支化聚(胺-酯)(HPAE);最后制备出不同HPAE含...     

Structure–properties relationship of starch/waterborne polyurethane composites

The blend materials from waterborne polyurethane (WPU)/starch (ST) with different contents (10–90 wt %) were satisfactorily prepared by using the solution casting method. Their miscibility, structure, and properties were investigated by wide‐angle X‐ray diffraction (WAXD), scanning electron microscope (SEM), different scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), and the tensile tests, respectively. The results indicated that tensile strength of composite materials not only depended on the starch content, but also related to the microstructure of WPU. The sample WPU2 (1.75 of NCO/OH molar ratio) exhibited hard‐segment order, but WPU1 (1.25 of NCO/OH molar ratio) had no hard‐segment order. The appropriate starch filled into WPU not only decreased the ordered region of soft‐segment matrix, but also hindered the formation of hard‐segment ordered structure. The blend material from 80 wt % WPU1 and 20 wt % starch exhibited better tensile strength (27 MPa), elongation at break (949%), and toughness than others. With an increase of starch content, the WPU matrix with dispersed starch in the blends transited to dual‐phase continuity and then to starch matrix with dispersed WPU. The results suggested that a certain extent of miscibility existed between WPU and starch in the blend materials on the whole composition ratio. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3325–3332, 2003     

Effect of novel aliphatic fluoro-diol content on synthesis and properties of waterborne polyurethanes

This study synthesized a waterborne polyurethane (WPU) prepolymer by using polytetramethylene glycol, isophorone diisocyanate, and 2,2,3,3,4,4,4-Heptafluoro-butynic acid 2,2-bis-hydroxymethyl-butyl ester (HFBA). Subsequently, a series of novel HFBA/WPUs were synthesized by adopting ethylenediamine as the chain extender. The results from Fourier transform infrared spectroscopy demonstrated that the CO groups of HFBA/WPUs shifted to lower wavenumbers as the HFBA content increased. Moreover, when the HFBA content of the synthesized HFBA/WPUs increased, the WPU initial decomposition temperature, glass transition temperature, tensile strength, and Young's modulus also increased. Furthermore, the results of atomic force microscopy identified a relatively high number of humpy protrusions and roughness levels in the HFBA/WPUs with a relatively high HFBA content, causing higher hydrophobicity of these HFBA/WPUs. Furthermore, in vitro platelet and erythrocyte adhesion experiments revealed that increasing the HFBA content lowered platelet and erythrocyte adhesion on the surface of the WPUs. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47356.     

内交联水性聚氨酯脲的制备及性能表征

以二羟甲基丙酸(DMPA)、异佛尔酮二异氰酸酯(IPDI)、乙二胺作为硬段,聚醚多元醇(GE220)为软段,以蓖麻油(CA)和三羟甲基丙烷(TMP)多元醇为内交联剂,制备了两个系列的交联型水性聚氨酯脲(PUU)分散液,测定了PUU水分散液及其膜的物理性能和力学性能.结果表明,与未交联的PUU水分散液相比,交联型PUU表现出较好的疏水性能,吸水率从52.4%下降到12.0%,力学性能也有较大程度的提高.随交联剂用量的增加,尽管水分散液的粒径略有增加,但成膜后的耐水性增强,力学性能提高.     

含羧基水性环氧树脂的制备及其性能研究

以烯丙基缩水甘油醚（AGE）和甲基丙烯酸（MAA）为原料,采用“一步法”,即基于自由基共聚理论,合成具有良好稳定性的含羧基水性环氧树脂。探讨了加料方式、引发剂种类及用量等因素对聚合物性能的影响,对含羧基水性环氧树脂的结构进行了红外、核磁表征,并将其应用于山羊酸皮的鞣制工序中。实验结果表明：采用氧化还原引发体系过硫酸铵和亚硫酸氢钠,过硫酸铵用量为11%,单体全部滴加的方式制得聚合物稳定性良好,转化率为98%。应用结果表明：聚合物单独鞣制后坯革的收缩温度可达71℃,增厚率达46%;配合3%铬粉鞣制后坯革的收缩温度为114.1℃,增厚率为104%;同时,与传统铬鞣法相比,此工艺方法有效降低了废液中的Cr2O3含量,减少了环境污染。     

Properties of waterborne polyurethane‐fluorinated marine coatings: The effect of different types of diisocyanates and tetrafluorobutanediol chain extender content

Three series of waterborne polyurethane‐ (WBPU) fluorinated coatings were prepared with single aliphatic (4,4′‐dicyclohexylmethane diisocyanate, H₁₂MDI), aromatic (4,4′‐diphenylmethane, MDI) and a mixture of aliphatic and aromatic diisocyanates (1 : 1). Different contents of 2,2,3,3‐tetrafluoro1,4‐butanediol (TFBD) as a chain extender were used in the WBPU coatings. The fluoro‐enriched surface of the WBPU coatings was obtained with a combination of a high TFBD content (8.77 mol %) as well as the aliphatic or mixed diisocyanates. The tensile strength, Young's modulus, elongation at break (%) and adhesive strength were characterized with respect to the TFBD contents. The mechanical strength and adhesive strength increased with increasing TFBD content in the three series. In artificial salt water, the maximum adhesive strength of WBPU was observed for this coating, which was achieved by TFBD bonded H₁₂MDI of mixed diisocyanates with a higher TFBD content (8.77 mol %). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39905.     

Structure and ionic conductive properties of polydioxolane–polyurethane‐based electrolytes

A series of polyurethanes (PUs) with different polyether soft segments [polydioxolane (PDXL), polyethylene glycol (PEG), or PDXL/PEG] were synthesized successfully, and solid polymer electrolytes based on PU/LiClO₄ complexes were prepared. The relations between structure and the ionic conductive properties of the PU‐based electrolytes were investigated by means of Fourier transform infrared spectroscopy, differential scanning calorimetry, dynamic mechanical analysis, and complex impedance analysis. Results showed that the glass‐transition temperature (T_g) of PDXL–PU was lower than that of PEG–PU. Doped lithium perchlorate (LiClO₄) salt could be dissolved well in soft segments of PDXL–PU. The ionic conductivity of the PDXL–PU/LiClO₄ complex could reach a value of 2 × 10^?5 S/cm at room temperature without the addition of an organic plasticizer. The system with PDXL/PEG as a soft segment had a higher T_g and a lower ionic conductivity than the one with PDXL as a soft segment. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 103–111, 2002     

蓖麻油改性聚醚型水性聚氨酯乳液的性能

以聚醚、甲苯二异氰酸酯(TDI)、一缩二乙二醇、蓖麻油为主要原料,二羟甲基丙酸(DMPA)为亲水扩链剂,三乙胺为中和剂制备了稳定的阴离子水性聚氨酯乳液(WPU),研究了NCO/OH摩尔比、DMPA及蓖麻油的加入量对WPU的耐水性、稳定性和力学性能的影响,结果表明:改性后的乳液具有较好的稳定性,适量的蓖麻油可提高胶膜的拉伸强度及耐水性。当聚醚与蓖麻油质量比为7︰3、DMPA为5%、NCO与OH摩尔比为1.3时,WPU综合性能最好。     

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