有机硅氧烷微乳液改性聚氨酯脲-丙烯酸酯复合水分散液的研究

用N-β.氨乙基-γ-氨丙基三甲氧基硅烷、辛基三乙氧基硅烷与表面活性荆OP-10,制备了室温贮存稳定性大于6个月的有机硅氧烷微乳液。后者与聚氨酯脲-丙烯酸酯(PUA)复合水分散液共混。制备了改性PUA复合水分散渡,并通过FT-IR、ATR、粒度分析、Zeta电位对改性水分散液以及成膜后的表面性能进行了表征。实验结果表明,与PUA复合水分散液相比,改性水分散液的粒径减小,粒径分布变宽。改性水分散液成膜后,表面呈现出很好的疏水性能和较低的表面能,与成膜过程中有机硅氧烷在膜表面的富集效应有关。     

有机硅氧烷微乳液改性聚氨酯脲-丙烯酸酯复合水分散液的研究

用N-β-氨乙基-γ-氨丙基三甲氧基硅烷、辛基三乙氧基硅烷与表面活性剂OP-10，制备了室温贮存稳定性大于6个月的有机硅氧烷微乳液。后者与聚氨酯脲．丙烯酸酯(PUA)复合水分散液共混，制备了改性PUA复合水分散液，并通过FT-IR、ATR、粒度分析、Zeta电位对改性水分散液以及成膜后的表面性能进行了表征。实验结果表明，与PUA复合水分散液相比．改性水分散液的粒径减小，粒径分布变宽。改性水分散液成膜后，表面呈现出很好的疏水性能和较低的表面能，与成膜过程中有机硅氧烷在膜表面的富集效应有关。     

改性纳米二氧化硅–丙烯酸酯聚氨酯乳液的制备及表征

以自制改性纳米Si O2水分散液、异佛尔酮二异氰酸酯(IPDI)、聚醚二元醇(N210)及甲基丙烯酸甲酯(MMA)等为原料,通过乳液聚合法制得改性纳米Si O2–丙烯酸酯聚氨酯乳液(Si O2–PUA)。通过傅里叶变换红外光谱、Zeta电位测试、热重分析和粒径分布测试等手段对乳液进行了表征,测试了漆膜的硬度、吸水率和耐醇性等性能,探讨了纳米Si O2添加量的影响。当纳米Si O2的添加量≤PUA含量的5%时,Si O2–PUA在469 cm-1处出现了明显的Si─O键弯曲振动峰,而PUA则没有,说明纳米Si O2与PUA可能发生了化学键合。添加5%改性纳米Si O2后,PUA乳液的Zeta电位由-46.5 m V变为-40.1 m V,绝对值减小,稳定性较好;热分解温度比PUA提高了35°C;胶粒平均粒径在纳米级,且Si O2粒子分散均匀;其漆膜硬度提高至4H,吸水率降为10.35%。     

含氟丙烯酸酯微乳液改性水性PUA

以全氟辛酸铵/十二烷基硫酸钠为复合乳化剂,过硫酸铵为引发剂,合成了丙烯酸丁酯(BA)与甲基丙烯酸-2-(全氟壬烯氧基)乙酯(FNEMA)共聚物微乳液(粒径为72 nm),并将其与聚氨酯脲-丙烯酸酯(PUA)水分散液进行了共混改性.结果表明,在基本上不影响改性PUA膜吸水率的前提下,改性PUA水分散液的表面张力明显下降,改性膜表面的疏水性显著增强.     

紫外光固化水性聚氨酯丙烯酸酯分散液流变行为

用甲苯二异氰酸酯、聚己二酸新戊二醇酯多元醇、二羟甲基丙酸(DMPA)和甲基丙烯酸羟乙酯合成了紫外光固化聚氨酯丙烯酸酯(PUA)水分散液。该预聚物组成通过FTIR和^1H-NMR进行了表征,并对其水分散液的流变行为进行了研究。结果表明,随预聚物中DMPA质量分数的增加,分散液由牛顿流体转变为非牛顿流体。当DMPA质量分数为6．68％时,PUA水分散液的粒径为40～70nm,ζ电位为-66．00mV,黏流活化能为59．08J／mol。     

聚脲/丙烯酸酯乳液的合成及性能研究

以异佛尔酮二异氰酸酯(IPDI)、聚醚胺D-2000、二羟甲基丙酸(DMPA)、丙烯酸羟乙酯(HEA)为原料,合成双键封端的聚脲预聚体,再通过种子乳液聚合法,与丙烯酸酯单体聚合,制备聚脲/丙烯酸酯(PUAA)乳液。研究了R值、DMPA用量以及聚脲(PUA)与聚丙烯酸酯(PA)质量比对合成乳液稳定性、耐水性、力学性能等的影响。红外光谱分析表明聚脲与丙烯酸酯成功接枝。实验结果表明:R值为1.6时,乳胶膜吸水率最低;而随R值增大,乳胶膜的拉伸强度增大,断裂伸长率减少。实验优选DMPA的用量占PUA预聚体的5.0%,PUA与PA质量比为2∶3~1∶2,制得的PUAA乳液稳定,吸水率低,力学性能好。     

丙烯酸酯改性蓖麻油基水性聚氨酯乳液的制备

以改性蓖麻油(MCO)、聚碳酸酯二醇(PCDL)、异佛尔酮二异氰酸酯(IPDI)、六亚甲基二异氰酸酯(HDI)和二羟甲基丙酸(DMPA)等为原料合成水性聚氨酯种子乳液,通过MCO的双键活性位实现丙烯酸酯(AC)单体的种子乳液聚合,得到聚氨酯–丙烯酸酯(PUA)乳液。通过FT–IR(傅里叶变换红外光谱)分析、激光粒度仪、旋转黏度计研究了AC单体含量及配比、助剂用量对PUA乳液性能的影响。通过电子拉力试验机、耐水试验和动态力学分析仪研究了不同AC含量PUA膜的力学、耐水和动态力学性能。结果表明:通过种子乳液共聚,PUA均显示一个玻璃化温度,说明聚丙烯酸酯与聚氨酯具有较好的相容性;当n(MCO):n(PCDL)=1.2,n(甲基丙烯酸正丁酯):n(甲基丙烯酸甲酯)=0.9,w(乳化剂SDS)为2.0%,w(引发剂AIBN)为0.2%时所合成的PUA稳定性最好,且具有适中的黏度和较好的粒径分布;随AC含量的提高,PUA胶膜耐水性提高,胶膜硬度和弹性模量逐渐提高,拉伸强度和伸长率均在w(AC)为10%时出现最大值。     

聚酯二元醇合成聚氨酯丙烯酸酯复合乳液的研究

以异佛尔酮二异氰酸酯(IPDI)、自制聚酯二元醇、二羟甲基丙酸(DMPA)和甲基丙烯酸甲酯(MMA)、苯乙烯(St)、丙烯酸丁酯(BA)为主要原料,合成了聚酯型聚氨酯丙烯酸酯(PUA)复合乳液,研究了不同相对分子质量的聚酯二元醇、聚氨酯制备时不同NCO/OH比值、添加三羟甲基丙烷(TMP)含量、及合成PUA时不同PU/PA的比值对最终制备的聚氨酯丙烯酸酯复合乳液及涂膜性能的影响。结果表明:1500～2000相对分子质量的聚酯二元醇:在TMP添加量为2%、NCO/OH为1.6～1.8,PU/PA以4︰6合成出的PUA,有着较好的制备稳定性和贮存稳定性,其涂膜硬度、耐水性和耐醇性较好。     

多官能度水性光敏聚氨酯丙烯酸酯的合成与表征

以异佛尔酮二异氰酸酯(IPDI)、丙三醇、聚四氧呋喃醚二醇(PTMO)、二羟甲基丙酸(DMPA)、季戊四醇三丙烯酸酯(PETA)为原料,合成了一种具有核壳结构的新型多官能度水性光敏聚氨酯丙烯酸酯(PUA)乳液.通过红外光谱(FT-IR)、凝胶渗透色谱(GPC)、核磁共振碳谱(13CNMR)、透射电镜(TEM)、动态热力学分析测试(DMA)等物理测试手段对聚合物结构进行了表征,并通过化学滴定测定C=C双键的含量.FT-IR、NMR分析表明,合成得到的树脂是带有多支链的多官能度水性光敏聚氨酯丙烯酸酯(PUA);GPC分析表明,合成的多官能度PUA聚合物的数均相对分子质量(Mn)和分散度(D)分别为11 374和3.75;TEM分析表明,乳胶粒呈现一定的核壳结构,形态较规则,大多数呈球形;DMA分析表明多官能度PUA聚合物涂膜的玻璃化转变温度为-39.4℃,tanδ曲线没有出现很明显的双峰或多峰,软段与硬段相容性好;化学滴定分析表明,此目标树脂中C＝C双键的最终含量为4.9 meq/g.     

聚合物结构对阳离子含氟PUA中性施胶剂的影响

研究了阳离子含氟聚氨酯-丙烯酸酯复合乳液(PUA)中性施胶剂的制备和应用,重点分析了亲水单体、聚丙烯酸酯、含氟丙烯酸酯对阳离子含氟PUA中性施胶剂应用效果和产品稳定性的影响,并用红外光谱(FTIR)和核磁共振氟谱(19F- NMR)对其结构进行了表征.结果表明,当用量为0.8％时,纸张的施胶度大于36.70s;乳液的ξ...     

Morphology and particle size of nanograde polyurethane/polyacrylate hybrid emulsions

Poly(urethane acrylate) (PUA) composite particles were prepared by seeded surfactant‐free emulsion polymerization. The aqueous polyurethane (PU) dispersions were used as seed particles. The diameters of the seed particles of the aqueous PU dispersions and PUA composite latexes were measured by dynamic light scattering. The microstructures of the PUA composite emulsion particles were observed by transmission electron microscopy. The influences of the amount of the hydrophilic chain extender, the types of initiators, and the PU/polyacrylate (PA) weight ratios on the diameters of the aqueous PU and composite emulsions were also studied. The results showed that the PUA composite emulsions formed a core–shell structure with PU as the shell and with PA as the core. The diameter of the PU seed particles and the particle size of the PUA composite emulsions greatly depended on the amounts of the hydrophilic chain extender used in the preparation of the PU seed; when the hydrophilic chain extender concentration was 7.4%, the average diameter of the PUA composite emulsion particles showed the minimum value. The types of initiators and PU/PA weight ratios did not have a significant influence on the diameter of the PUA composite latex particles. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

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     

聚氨酯脲－乙烯基聚合物复合水分散液

以蓖麻油、二官能度聚醚多元醇（ＧＥ ２１０）、苯乙烯和丙烯酸丁酯等原料合成了聚氨酯脲－乙烯基聚合物（ＰＵＡ）复合水分散液,并研究了这类水分散体系的粒子形态、流变性能以及稳定性。结果表明,分别由蓖麻油以及蓖麻油与ＧＥ ２１０质量比为１／ｌ合成的ＰＵＡ分散液中的分散相呈现出较好的核壳结构,分散液的粘度较小,接近于牛顿流体,且体系的电位绝对值和临界聚沉浓度较大。由ＧＥ ２１０合成的ＰＵＡ复合水分散液中未观察到规则的分散粒子,分散液的粘度较大,表现为假塑性流体,且对电解质较敏感。     

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.     

Stabilization of PCC dispersions prepared directly in the mother-liquid after synthesis through the carbonation of (hydrated) lime

Various CaCO₃-based products are often used in the form of concentrated aqueous dispersions. This study investigates the stabilization of PCC dispersions prepared directly in the mother-liquid after the carbonation of (hydrated) lime through the adsorption of a commercial sodium polyacrylate dispersant. The results demonstrate that the composition of the mother-liquid, particularly the Ca²⁺ activity, profoundly influences virtually all processes pertinent to dispersion stabilization—from the initial charging of the CaCO₃ surface in base PCC dispersions, to the surface charge regulation and dispersion stabilization efficiency of the polyacrylate dispersing agent. Rising prominence of the counterion condensation effects in Ca²⁺ rich solutions limits the conditions conducive to the surface charge regulation through dispersant adsorption to an optimum pH range of about 8-11. Furthermore, dispersion stability analysis, based on the classical DLVO theory of colloid stability, and corroborated by experimental evidence in the form of particle size distribution analyses, also indicates that optimum stability conditions for such PCC dispersions are established with small dispersant doses (0.25-0.5% per dry weight) in the pH range of about 9-11.     

Waterborne Polyurethane-Acrylate Containing Different Polyether Polyols: Preparation and Properties

The waterborne polyurethane–acrylate (PUA) was prepared based on isophorone diisocyanate, polyether polyol, dimethylol propionic acid, hydroxyethyl methyl acrylate, butyl acrylate (BA) and styrene (St). Fourier transform infrared spectrometry (FT-IR), Ultraviolet-visible spectrophotometry (UV-Vis) and Differential scanning calorimetry (DSC) were employed to investigate the structures, optical transparency and thermal properties. Some physical properties of the aqueous dispersions such as viscosity, particle size and surface tension were measured. Some mechanical performances and solvent resistance of films were investigated. When the ratio of the BA/St was 30/70, the films had excellent water and alkali resistances. The obtained PUA composites have great potential application such as coatings, leather finishing, adhesives, sealants, plastic coatings and wood finishes.     

一步法制备含羟基聚氨酯水分散体

以甲苯二异氰酸酯(TD I)、聚酯二醇和二羟甲基丙酸(DMPA)等为原料,采用一步法工艺制备了含羟基聚氨酯水分散体,探讨了聚酯二醇的种类、DMPA含量和NCO/OH摩尔比、中和剂及用量等对水分散体稳定性的影响,利用红外和粒度分析等方法表征了该体系的结构和胶粒尺寸。实验结果表明,随着亲水性离子用量增加,水分散体的粒径变小,稳定性增强,且在同样条件下采用不同的聚酯二醇制备的分散体粒径有一定的差异;采用JS307-110和JS308-110为原料时,最佳的NCO/OH摩尔比分别为0.91和0.85左右,其分散体粒径分别为60 nm和90 nm;采用三乙胺为中和剂,中和度为90%~100%时可得到稳定的水分散体。     

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     

Waterborne polyurethane and modified polyurethane acrylate composites

Abstract

Waterborne polyurethane (PU) and a series of PU acrylate (PUA) composite dispersions were synthesised from isophorone diisocyanate, polyester polyols, dimethylol propionic acid, hydroxyethyl methyl acrylate, butyl acrylate and methyl acrylate. Fourier transform infrared, ultraviolet visible and differential scanning calorimetry were used to demonstrate structures, optical transparency and thermal stabilities of PU and PUA. The PUA sample had lower glass transition temperature of hard segment and higher decomposition temperature than the PU sample. Performances of the dispersion and film were studied by means of apparent viscidity, particle size and particle size distribution index, surface tension and mechanical property. The results indicated that the solvent resistance and mechanical property of PUA film were improved compared with the pure PU film. The obtained stable PUA composite samples have excellent integrated properties and have a great potential application in meeting the highly diversified demands in modern technologies, such as coatings, leather finishing, adhesives, sealants, rubbers, plastic coatings and wood finishes.     

Influence of Acidity on the Electrostatic Stability of Alumina Suspensions in Ethanol

Alumina (Al₂O₃) powders have been dispersed in ethanol (EtOH) solutions of different acidity. In aqueous media, acidity is defined by pH. This definition can be extended to nonaqueous media using ion-transfer functions. The electrical charge on the particle surfaces has been found to be acidity dependent. The electrostatic stability of Al₂O₃EtOH suspensions has been evaluated via electrophoresis and turbidity. An electrostatic stabilization mechanism is proposed and analyzed via Derjaguin–Landau–Verwey–Overbeek (DLVO) theory.