丙烯酸酯/聚氨酯三层核壳复合乳液的合成与表征

以自制的聚酯多元醇(PPMBA)、甲苯二异氰酸酯(TDI)、1,6-六亚甲基二异氰酸酯(HDI)、二羟甲基丙酸(DMPA)合成聚氨酯预聚体,再用丙烯酸酯类单体代替有机溶剂对预聚体降黏,封端预聚体后中和分散乳化得包含丙烯酸酯类单体的聚氨酯乳液.向乳液中加入引发剂引发自由基聚合得到复合乳液,最后再加入乙烯基类单体及引发剂合成三层核壳结构的聚丙烯酸酯/聚氨酯复合乳液.研究表明,二异氰酸酯的-NCO与聚酯多元醇中的-OH的物质的量之比(R值)为1.6~4之间时,随R值增加,乳液稳定性增强;DMPA含量在4%~7%的范围内,随DMPA含量的降低,乳胶膜的耐水性提高.通过红外光谱对所合成聚酯多元醇及复合乳液结构进行表征.     

单油酸三羟甲基丙烷酯改性水性聚氨酯

利用单油酸三羟甲基丙烷酯(TMPM)、异佛尔酮二异氰酸酯(IPDI)和聚氧化丙烯(PPG)等制备水性聚氨酯。采用透射电镜(TEM)、动态激光光散射(DLLS)、红外光谱(FT-IR)、热重分析(TGA)和表面张力仪表征了乳液胶束形态、产物结构及性能。结果表明:水性聚氨酯(PU)分子上引入脂肪侧链容易在水中形成规整的胶束,但TMPM改性的水性聚氨酯胶束粒径随TMPM含量的增加不断增大,当w(TMPM)=0.07时,乳液不稳定;脂肪侧链的引入降低了水性聚氨酯乳液的表面张力,表面张力随着反应体系中—NCO和—OH摩尔比的增大而降低,随交联度的增大先增加后减小;TMPM的引入可以提高胶膜的热稳定性。     

环氧改性水性聚氨酯乳液的制备及其膜性能

以聚己内酯二元醇(CAPA)为软段,异佛尔酮二异氰酸酯(IPDI)和六亚甲基二异氰酸酯(HDI)为硬段,环氧树脂E-44为大分子交联剂,经相转化法合成了一系列环氧树脂改性负离子水性聚氨酯(EPPU)自乳化乳液,并制备了改性水性聚氨酯的固化膜.通过FTIR、TGA及接触角、力学性能测试对聚合物结构及其膜性能进行了研究.通过原子力显微镜(AFM)观察膜表面形态和表面粗糙度.乳液粒径及粒径分布通过动态激光光散射法(DLLS)测定.FTIR分析表明环氧树脂的羟基和环氧基都参与了发应.TGA表明,环氧树脂的加入可以提高聚氨酯的热稳定性.随着w(E-44)增大,改性聚氨酯膜的拉伸强度得到改善,断裂伸长率减小.随着w(E-44)增大,乳液粒径增大,薄膜的接触角增大,改性后的PU膜表面光滑度下降,拒水性增强.     

水性聚氨酯结构与胶膜性能的关系

为制备一种性能优异的水性聚氨酯涂层,以聚丙二醇和异佛尔酮二异氰酸酯为主要原料,用本体聚合法制备了水性聚氨酯,考察了结构组元对胶膜性能的影响,并用激光粒度仪、微机控制电子万能试验机和同步热分析仪进行了表征。结果表明:当硬段含量增加时,乳液粒径增大,胶膜拉伸强度增加,吸水率升高;当异氰酸根指数增大时,乳液粒径增大,胶膜拉伸强度增加,吸水率降低;当亲水性扩链剂含量和中和度增大时,乳液粒径减小,胶膜的拉伸强度增加,吸水率升高;在硬段比例为50%、异氰酸酯指数为1.35、亲水性扩链剂含量为5%、中和度为1的条件下,胶膜性能较佳(拉伸强度为16MPa,断裂伸长率为556%,吸水率为6.2%)且在丙酮和甲苯中均表现出溶胀现象。     

PCDL型超支化水性聚氨酯的合成与性能

以甲苯-2,4-二异氰酸酯（TDI）、聚碳酸酯二醇（PCDL）、二羟甲基丙酸（DMPA）和二乙醇胺（DEOA）为原料,采用A₂＋bB₂共聚合路线合成了具有超支化结构的水性聚氨酯（HBAPU）乳液。采用红外光谱（FT-IR）、核磁共振（13C NMR）对产物结构进行了表征,证实了超支化聚氨酯的支化度随 n(NCO)/n(OH)比值的增大而增大。用PCS、TG、电子拉力机对产物的性能进行了测试,同时也对胶膜的耐水性进行了测试,发现在DMPA含量为0.4 mmol/g时,HBAPU的粒径仅有20.57 nm,而线性水性聚氨酯粒径有130.91 nm,并且HBAPU具有良好的耐水性、热稳定性和较高的拉伸强度。     

纳米氧化锡锑改性水性聚氨酯的制备与表征

以异佛尔酮二异氰酸酯(IPDI)、聚醚二醇（N-210）、二羟甲基丙酸（DMPA）、一缩二乙二醇（DEG）、三羟甲基丙烷（TMP）及纳米氧化锡锑（ATO）浆料为主要原料,制备了稳定的纳米ATO改性水性聚氨酯(APU)乳液。 粒径测试及透射电子显微镜（TEM）观察显示,纳米ATO在水性聚氨酯中分散较好,乳液粒径均小于100 nm; FTIR分析表明,纳米ATO粒子与水性聚氨酯(WPU)间可能存在化学键; 热重分析(TGA)测试显示,随纳米ATO添加量的增加,胶膜最大热分解温度逐渐提高,最大提高了约20 ℃;紫外-可见-近红外吸收及保温性能测试表明,随着纳米ATO添加量的提高,胶膜在800~2500 nm的透过率逐渐降低,但涂层在可见光区透过率均超过70%,热阻率由1.34×10-2 m2·℃/W提高至3.17×10-2 m2·℃/W。     

芳香族偶氮苯封端的液晶聚氨酯膜的制备及其液晶性能

以苯胺或对硝基苯胺为主要原料,经重氮偶合反应制得液晶基元对氨基偶氮苯(LC1)或对硝基偶氮苯胺( LC2),再用聚氨酯预聚体[由聚乙二醇(PEG400,含-OH)和二苯基甲烷二异氰酸酯(MDI,含-NCO)制得,r=n(-OH)∶n(-NCO)]封端合成了一系列偶氮液晶聚氨酯膜LCPU'1和LCPU'2,其结构和液晶性能经UV,IR,TGA,POM与XRD表征.结果表明,LCPU'1和LCPU'2为具有良好热稳定性的热致型向列型液晶聚氨酯.LCPU3/41的接触角较大,耐水性相对较佳,硬度也相对适中.     

酮肼交联及硅烷偶联水性聚氨酯的成膜机理及其性能研究

用二乙醇胺(DEA)和双丙酮丙烯酰胺(DAAM)按Michael加成反应机理合成了一种新的聚氨酯扩链剂DDP(N-[(1,1-二甲基-2-乙酰基)乙基]-β-二羟乙氨基丙酰胺).以异佛尔酮二异氰酸酯(IPDI)、聚四氢呋喃二醇(PTMG1000)、二羟甲基丙酸(DMPA)、三羟甲基丙烷(TMP)等为主要原料,在用γ-氨基丙基三乙氧基硅烷(KH550)封端改性聚氨酯的基础上,采用自制含酮羰基二元醇N-[(1,1-二甲基-2-乙酰基)乙基]-β-二羟乙氨基丙酰胺(DDP)和1,4-丁二醇(BDO)作为扩链剂,制备了侧链含酮羰基的聚氨酯乳液.通过外加己二酸二酰肼(ADH),制得室温自交联乳液.利用衰减全反射红外光谱(ATR-FTIR)和核磁共振波谱(NMR)对扩链剂(DDP)和涂膜结构进行表征,ATR-FTIR和NMR测试证实了DDP的生成并参与反应合成了聚氨酯及乳液成膜时酮肼交联反应的发生.研究了n(—NHNH2)/n(—CO—)、n(NCO)/n(OH)、DDP含量对聚氨酯涂膜性能的影响.结果表明,在己二酸二酰肼(ADH)的用量为0时,涂膜的吸水率随DDP含量的增加而增大;n(NCO)/n(OH)1.40时,聚氨酯难以乳化并且乳液稳定性变差;在最佳配比n(—NHNH2)/n(—CO—)=1,n(NCO)/n(OH)=1.40的条件下,DDP%从0增大到7.22%时,涂膜的吸水率从39.36%降低到18.92%同时表现出很好的耐溶剂性能,交联度从51.49%上升至90.23%,拉伸强度从20.09MPa增大到28.26MPa,硬度达2H.热失重分析(TGA)表明酮肼交联结构的引入提高了涂膜的热稳定性.     

高固含量低黏度聚氨酯微乳液的制备及性能研究

以聚(四氢呋喃-co-氧化丙烯)二醇(Ng210)为软段,异佛尔酮二异氰酸酯(IPDI)为硬段,以1,2-二羟基-3-丙磺酸钠(DHPS)和二羟甲基丙酸(DMPA)作为亲水扩链剂,采用自乳化法合成了一系列了高固含量低黏度稳定聚氨酯微乳液,分析了DHPS和DMPA质量配比对乳液性能的影响,结果表明,所得乳液粒径呈多元分布,乳胶粒子呈球形;乳液为假塑性流体,表观黏度小于250mPa.s(剪切速率为25s-1)且随切变速率的变化规律呈现一定的切力变稀特征;随着DHPS/DMPA比值的增大,胶粒平均粒径逐渐减小,多分散性增强;当DHPS/DMPA值为4/10～6/10时,乳液中大小粒子粒径比为6～8,且大乳胶粒子的体积分数约为70%～75%,乳液的固含量均大于70%.另外,乳液具有较好的低温和高温以及贮存稳定性,具有较低的表面张力,相对于常规的聚氨酯乳液,所制备的高固含量聚氨酯乳液胶膜具有更好的力学性能.     

环氧大豆油多元醇改性磺酸型水性聚氨酯合成与性能研究

用2-乙基己醇(异辛醇)对环氧大豆油进行开环,生成环氧大豆油多元醇,并利用其对由异佛尔酮二异氰酸酯(IPDI)、聚己内酯二元醇(PCL)和乙二胺基乙磺酸钠(AAS)为主要合成原料的磺酸型水性聚氨酯(SWPU)进行改性,考察了不同多元醇含量对磺酸型水性聚氨酯乳液以及胶膜性能的影响.首先,通过FTIR和1H-NMR证实了环氧大豆油多元醇的合成;然后经过粒径测试、耐水性测试、接触角测试、机械性能测试、TG测试等检测表明:磺酸型水性聚氨酯成功合成,随着多元醇含量的增加,水性聚氨酯乳液粒径逐渐增大;胶膜的吸水率逐渐减小,并趋于平缓;力学性能拉伸强度逐渐增强,而断裂伸长率下降.但当环氧大豆油多元醇添加量过大时,导致最后乳液无法分散,乳化失败.当多元醇含量与PCL质量比为0.2时,胶膜吸水率由50.14%减小至12.27%,接触角为103.3°,拉伸强度由8.16 MPa增至21.77 MPa.通过TG表明,分子结构中多元醇的引入,胶膜的耐热性有明显提高.     

Structure and properties of polyurethane/polyacrylate latex interpenetrating networks hybrid emulsions

Some new kinds of novel polyurethane (PU)/polyacrylate (PA) latex interpenetrating networks (LIPNs) were synthesized. Firstly PU dispersions were synthesized by self-emulsification polymerization. Then PU/PA LIPNs using PU dispersion as the seed were prepared by soap free emulsion polymerization. The effects of different PU/PA ratios, the blending method and the NCO/OH molar ratio of PU components on PU/PA LIPNs performance were also investigated. The structure and properties of PU/PA LIPNs such as mechanical properties, particle size, morphology of the surface were characterized by dynamic mechanical analysis, scanning electron microscopy, and dynamic light scattering. It was found that PU/PA LIPNs can markedly improve the water resistance and the mechanical properties of PU latex much more than those of PU/PA physical blends due to a great deal of interpenetrating and entangling between PU and PA latex. Moreover, the particle size of PU/PA LIPNs is related to the PA content and NCO/OH molar ratio of PU components: the higher the NCO/OH molar ratio in PU dispersions, the larger is the particle size of PU/PA LIPNs, and the average particle size of PU/PA LIPNs becomes larger with an increase in PA content.     

Effect of Molecular Weight of WPU on the Heterogenic PUA Composite Latex Prepared by Soap-Free Emulsion Polymerization

Aqueous acrylic-polyurethane (PUA) composite emulsion was prepared by soap-free seeded emulsion copolymerization. Waterborne polyurethane (WPU) was used as the seeded emulsion and functioned as surfactant. The effect of molecular weight of WPU on the heterogenic was investigated. The molecular weight of WPU was controlled by varying the NCO/OH mole ratio. The GPC results confirmed that the molecular weight of WPU presented double distribution. And the molecular weight of WPU decreased with the increasing NCO/OH mole ratio. Surface tension test indicated that the molecular weight had little influence on the surface activity of WPU. However, after emulsion copolymerization of acrylic monomers, the morphology and properties of the PUA composite were impacted markedly by the molecular weight of WPU. With an increase in the NCO/OH mole ratio, the morphology of PUA composite latex changed from core-shell structures to fish bowl structure, and the mechanical properties of PUA films changed correspondingly.     

聚氨酯脲-丙烯酸酯水分散液的粒径及形态研究

研究了羧基含量、异氰酸酯指数（［ － ＮＣＯ］／［ － ＯＨ］） 、聚氨酯脲与聚丙烯酸酯组成比（ＰＵＵ／ＰＡ） 以及一系列制备工艺因素对聚氨酯脲—丙烯酸酯（ＰＵＡ） 水分散液粒子尺寸及形态的影响。结果表明：羧基含量和ＰＵＵ／ＰＡ 组成比增大或异氰酸酯指数减小都会导致分散液粒径减小;ＰＵＡ 中ＰＡ 含量越大,ＰＵＡ 水分散液粒子形态越不规整;工艺因素如搅拌强度、升温速率等对ＰＵＡ 水分散液粒子尺寸及形态的影响不符合传统乳液聚合的规律。     

Waterborne polyurethane/NiAl‐LDH/ZnO composites with high antibacterial activity

Novel waterborne polyurethane (WPU) composites based on NiAl‐LDH and ZnO were successfully synthesized by in‐situ polymerization. The nanostructured NiAl‐LDH/ZnO was first grafted by isophorone diisocyanate (IPDI), forming the NiAl‐LDH/ZnO‐NCO complex with ―NCO group on the surface, which promotes its homogeneous dispersion in WPU matrix. The microstructure and particle distribution of the composites were characterized. The mechanical properties and the water resistance of the composites were improved. Furthermore, the composites also exhibit significant antibacterial activity towards G(?) Escherichia coli and G(+) Staphylococcus aureus. Copyright © 2015 John Wiley & Sons, Ltd.     

Preparation of Aqueous Polyurethane Dispersions Using Aromatic Diisocyanate

Aqueous polyurethane dispersions were prepared by the reaction of hydroxyl-terminated poly(ethylene adipate), ethylene glycol, dimethylol propionic acid and aromaic diisocyante, 4,4′-diphenylmethane diisocyanate. The influence of molecular weight of oligoester and molar ratio between isocyanate and hydroxyl groups (NCO/OH) in the prepolymerization step were investigated. Molecular weight, particle size and particle size distribution were measured and compared. It was verified that the molecular weight increases with increasing in NCO/OH molar ratio. The results suggest that the hard segment content plays an important role in particle size and particle size distribution of the dispersions.     

非离子型可聚合聚氨酯/苯乙烯的超浓乳液聚合

研究了以非离子型可聚合聚氨酯(PUAG)和苯乙烯(St)为混合单体的超浓乳液聚合, 并且考察了n(NCO)/n(OH)摩尔比、复合乳化剂体系质量浓度[E]、不同乳化剂的种类、引发剂质量浓度[I]、单体体积分数(或分散相体积分数, 也称内相比Φ)、聚合温度等因素对聚合稳定性、动力学的影响. 同时结合光相关光谱(PCS)测定了聚合物乳胶粒子大小和粒径分布, 用透射电子显微镜(TEM)观察了粒子形态, 结果表明: 当n(NCO)/n(OH)＝2∶1, T＝328 K, Φ＝80.39%, [I]＝0.8% g/g (PUAG-St), [E]＝0.22 g/mL H₂O, m(MS-1)/m(CA)＝2∶1, PVA＝0.01 g/mL H₂O时, 超浓乳液不仅有较好的聚合稳定性和较快的聚合速率, 而且粒径小分布均匀. 同时, 在此条件下的表观动力学表达式和表观活化能分别确定为R_p＝k[I]^0.50[E]^0.73[M]^0.54和 E_a＝29.7 kJ/mol. 热失重分析(TGA)进一步表明: 调节PUAG的含量可以达到对聚苯乙烯的改性, 提高聚苯乙烯的热稳定性.     

Preparation and characterization of ultrafine Fe-Cu-based catalysts for CO hydrogenation

The ultrafine particles of a new style Fe-Cu-based catalysts for CO hydrogenation were prepared by impregnating the organic sol of Fe（OH）3 and Cu（OH）2 onto the activated Al2O3, in which the organic sol of Fe（OH）3 and Cu（OH）2 were prepared in the microemulsion of dodecylbenzenesulfonic acid sodium（S）/n-butanol（A）/toluene（O）/water with V（A）/V（O） = 0.25 and W（A）/W（S） = 1.50. This catalyst was characterized by particle size analysis, XRD and TG. The results of particle size analysis showed that Fe（OH）3 particles with a mean size of 17.1 nm and Cu（OH）2 particles with an average size of 6.65 um were obtained. TG analysis and XRD patterns suggested that 673 K is the optimal calcination temperature. CO hydrogenation produced C＋OH with a high selectivity above 58 wt% by using the ultrafine particles as catalyst, and the total alcohol yield of 0.250 g·ml^-1 ·h^-1 was obtained when the contents of Al2O3 and K were 88.61 wt% and 1.60 wt%, respectively.     

New route to 3-methacryloxypropyltrimethoxysilane-base organic–inorganic hybrid film

A series of poly(3-methacryloxypropyltrimethoxysilane)/waterborne polyurethane (PMPS/WPU) composite latexes and organic–inorganic hybrid films with PMPS contents of 0, 10, 20, 30, 40 and 50 wt.% were prepared via seeded emulsion polymerization initiated by AIBN and hydrolysis–condensation process of PMPS during the evaporation of water, respectively. WPU, that is anionic polyurethane emulsion, was synthesized using isophorone diisocyanate, polytetramethylene ether glycol, dimethylol propionic acid, 1,4-butanediol, and triethylamine. An investigation of transmission electron microscopy confirmed the core–shell morphology of the composite latex particle which was composed of a PMPS core and a polyurethane shell. A dynamic light scattering analysis showed that the average particle size distributed in the range of 42–134 nm. The proposed novel preparation method included the use of polyurethane as macromolecular emulsifier and steric stabilizer, control of (3-methacryloxypropyltrimethoxysilane) (MPS) content less than 50 wt.%, slow addition of MPS and application of AIBN ensured the preparation of a stable PMPS/WPU composite latex. Formed PMPS/WPU organic–inorganic hybrid film with high PMPS content via sol-gel process had uniform transparency at visible band because of less crystalline and phase separation between organic and inorganic phases.     

Synthesis and properties of room temperature curable trimethoxysilane‐terminated polyurethane and their dispersions

The purpose of this research is to study the synthesis and characterization of stable aqueous dispersions of externally chain extended polyurethane/urea compositions terminated by hydrolyzable or hydrolyzed trialkoxysilane groups incorporated through secondary amino groups. These dispersions with excellent storage stability are substantially free from organic solvents which cure to water and solvent resistant, tough, scratch resistant, preferably light stable (non‐yellowing) silylated polyurethane (SPU) films. The films were characterized by FT‐IR, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), tensile strength and water contact angle measurements, nanoindentation, gel content, water and xylene swellability tests. The properties of the films were discussed and correlated in detail by changing length of soft segment, diisocyanates, NCO/OH ratio and chain extender, ethylenediamine (EDA). From the results, it was found that the particle size and viscosity are lower whereas the gel content and thermal stability are higher for SPUs. Modulus, hardness and tensile properties of SPU films are superior compared to EDA‐PU film. Higher water contact angle and residual weight percentage of SPU films confirm silylation of PU by [3‐(phenylamino)propyl]trimethoxysilane (PAPTMS). Increase in NCO/OH ratios consumes more quantity of PAPTMS which makes PU with superior mechanical properties. Higher PAPTMS content in SPU results in effective crosslinking of the functional silanol groups formed by hydrolysis reaction of trimethoxysilane groups. Overall, SPUs synthesized at 1.4 NCO/OH ratio using Poly‐(oxytetramethylene)glycol (PTMG)‐2000 and isophorone diisocyanate (or) toluene‐2,4‐diisocyanate have excellent properties compared to SPUs prepared using PTMG‐1000 and at 1.2 and 1.6 NCO/OH ratios. SPUs prepared at 1.6 NCO/OH ratio are brittle due to higher crosslinking density. In addition, the crosslinking density of the films can be modified through silane end‐group modification to produce SPUs with a wide range of physical properties. Copyright © 2007 John Wiley & Sons, Ltd.