氨基硅油扩链改性水性聚氨酯的合成及性能研究

采用甲苯二异氰酸酯(TDI)、聚氧化丙烯二醇(PPG)、2,2-二羟甲基丙酸(DMPA)为原料,先制备成聚氨酯预聚体,再通过在乳化过程中以侧链氨基硅油(AEAPS)或直链氨基硅油(ATPS)扩链制得了一系列水性聚氨酯乳液,并对涂膜的红外光谱、耐水性、力学性能和表面疏水性等进行了研究。结果表明,通过氨基硅油改性的聚氨酯涂膜,在保持力学性能基本不变的情况下,其耐水性、表面疏水性等性能都有明显提高。其中,侧链氨基硅油(AEAPS)比直链氨基硅油(ATPS)具有更好的改性效果。     

氨基硅油扩链改性水性聚氨酯的研究

通过将由甲苯二异氰酸酯与聚四氢呋喃,二羟甲基丙酸反应制得的聚氨酯预聚体在低浓度氨基硅油的水乳液中扩链,合成了一种硅氧烷改性的聚氨酯水乳液,并用傅立叶红外光谱,ＥＳＣＡ能谱,接触角仪,电子拉力试验机,吸水率测定及乳液稳定性测试对其进行研究。     

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.     

不饱和糖功能单体接枝聚氨酯膜的制备及其血液相容性

通过葡萄糖、丙烯酸羟乙酯和丁二胺反应,制备了含不饱和双键的糖基功能单体。 采用傅里叶红外光谱和核磁共振氢谱对合成的产物进行结构表征确定。 采用紫外光引发接枝聚合技术,将制备的不饱和糖单体接枝聚合到聚氨酯膜的表面,以衰减全反射模式下傅里叶红外光谱对表面接枝反应进行了确认。 通过静态水接触角实验和血小板黏附实验,分别对改性聚氨酯膜表面的亲水性和血液相容性进行了研究,结果表明,改性聚氨酯膜表面的接触角从86°降低到45°,血小板的粘附量由14.36×10³ cells/mm²减少到2.57×10³ cells/mm²,亲水性明显增强,血液相容性显著改善。     

Simple method of fabrication of hydrophobic coatings for polyurethanes

The aim of this study was to develop a method of manufacturing versatile hydrophobic coatings for polymers. Authors present a simple technique of polyurethane (PU) surface modification with covalently attached silicones (PDMS) or fluorocarbons (PFC). Diisocyanates were applied as linker molecules. The obtained coatings were characterized using spectroscopic analysis (FTIR), scanning acoustic microscopy (SAM) and water contact angle measurements. FTIR analysis revealed high efficiency of grafting reaction. The results of contact angle measurement indicated significant increase of hydrophobicity — from 66° (unmodified PU) to 113° (PU grafted with PDMS) and 118° (PU grafted with PFC). Acoustic microscopy analysis confirmed satisfactory homogeneity and smoothness of the fabricated layers. In vitro cell tests revealed non-adherent properties of the surfaces. Both, MTT assay and fluorescence staining confirmed non-cytotoxicity of the coatings, which makes them potential candidates for use in biomedical applications.      

Novel porous polyurethane films

Polyurethane films treated in a two-stage process with aqueous bromine and ammonia solutions underwent significant modifications in crystalline and surface structure as well as in mechanical and physical properties. Bromine was sorbed on the film, and formed several charge transfer complexes with the soft and hard segments of the polyurethane as well as bridges between adjacent chains. In the second stage, ammonia reacted with the sorbed bromine producing gaseous nitrogen and ammonium bromide. The expansion of the gas resulted in a repacking of the polymeric chains and the formation of a porous structure. The bromine concentrations used and the times of contact between the films and the bromine were 0.02–0.06 normal and 1–10 min, respectively. The contact angle of the films decreased, depending on treatment conditions, from 73 to 20. The water vapor permeability increased three-fold. The treatment appeared to bring about a crystallization in the hard as well as in the soft segments of the PU as shown by differential scanning calorimetry measurements. Possible applications of the treated films for wound dressing are discussed. © 1998 John Wiley & Sons, Ltd.     

Facile fabrication of hydrophobic octadecylamine-functionalized polyurethane foam for oil spill cleanup

To improve the hydrophobic property of polyurethane foam for oil spill cleanup, the polyurethane foam with nitrile groups is modified by grafting with oleophilic octadecylamine. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and optical contact angle measuring device are used to characterize the modified polyurethane foam. The results show that the octadecylamine has been successfully grafted onto the polyurethane foam and improved the foam hydrophobicity. The modified foam exhibits higher contact angle (146.3 ± 2.8°) compared to the unmodified foam (121.4 ± 3.2°). Moreover, the water sorption of the modified foam is 0.11g/g, which is much lower than that of the unmodified foam (0.84g/g). On the other hand, the sorption capacity of the modified foam for toluene, gasoline and diesel sorption is increased by 20?40%. Therefore, the polyurethane foam prepared by us can be effectively used in oil/solvent spill cleanup.     

聚氨酯改性氟代聚丙烯酸酯的合成、表征与膜形态

在二月桂酸二丁基锡(T-12)作用下,将1,6-已二异氰酸酯(HDI)与聚乙二醇(PEG-200)在70℃反应合成—NCO封端的聚氨酯预聚体(PU),然后滴加甲基丙烯酸十二氟庚酯(RfAA)、丙烯酸羟丙酯(HPAA)和偶氮二异丁腈(AIBN)在甲基异丁基甲酮(MIBK)溶液中聚合反应4～6 h,再经丁酮肟(EtAO)封端,制得了一种新型聚氨酯改性氟代聚丙烯酸酯易去污整理剂(FPUA)。用红外光谱(IR)、核磁共振氢谱(1H-NMR)、核磁共振碳谱(13C-NMR)、原子力显微镜(AFM)和扫描电镜(SEM)等对FPUA的结构、成膜形态及应用性能进行了研究。结果表明:FPUA在亲水性纤维织物和单晶硅表面均能形成非单一结构的疏水膜。该膜附着在纤维表面,能使处理后织物表面水的静态接触角达到146.5°,色拉油的接触角达到132°,且易去污效果良好。     

Interfacial structure and properties of polyurethane/poly(methylacrylate-co-styrene) coating to regenerated cellulose film

A semiinterpenetrating polymer network (IPN) containing 72 wt % polyurethane (PU) and 6 wt % poly(methylacrylate-co-styrene) [P(MA-St)] was coated onto surfaces of regenerated cellulose (RC) film, which was prepared by coagulating a cellulose cuoxam from bagasse pulp. The interfacial structures, bonding manner, and the strength of the coated film were studied by infrared (IR),¹³C nuclear magnetic resonance (NMR), differential thermal analysis (DTA), transmission electron microscopy (TEM), and electron probe microscopy analysis (EPMA). It was shown that the RC film coated with PU/P(MA-St) has strong interfacial interactions, where covalent and hydrogen bonds are formed across the interface between cellulose and the PU/P(MA-St) coating. The interfacial structure of the coated film is regarded as a shared PU network crosslinked simultaneously with P(MA-St) and cellulose film. The tensile strength, water resistivity, and optical transmission of the coated films were considerably higher than that of the uncoated films. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35 : 2495–2501, 1997     

Surface characteristics of chitin-based shape memory polyurethane elastomers

Shape memory polyurethanes (SMPUs) were prepared from polycaprolactone diol 4000 (PCL 4000), 1,4-butanediol (BDO), chitin, dimethylol propionic acid (DMPA), triethylamine (TEA) and 4,4′-diphenylmethane diisocyanate (MDI), and the structures of the synthesized materials were verified by infrared spectroscopy. The effects of chitin and DMPA contents in the polyurethane formulation on surface properties were investigated. DMPA provides function of making hydrophilic polyurethanes. The crystalline structure of chitin enhanced the hydrophobicity of the synthesized materials. Contact angle, water absorption, surface free energy, work of water adhesion and swelling behavior of the synthesized polyurethanes were affected by varying the DMPA and chitin contents. The interactions of the PU films with solvents on the surface were clearly related to the contents of DMPA and chitin in the final polyurethane formulation.     

微结构与表面修饰对二氧化硅多孔薄膜疏水性能的影响

通过引入聚乙二醇(PEG)改性传统二氧化硅(SiO2)溶胶,得到了粒径分布较宽且粒径可控的溶胶。比较了六甲基二硅氮烷(HMDS)溶胶内修饰和薄膜表面修饰以及溶胶粒径对SiO2薄膜疏水性能的影响。采用动态光散射粒度仪定量测试了二氧化硅溶胶老化过程中粒度的变化,用原子力显微镜、接触角测试仪、红外光谱仪、紫外-可见-近红外分光光度计分别对薄膜的表面形貌、表观静态接触角、薄膜成分及透光率等进行了测量。结果表明:PEG的添加可有效增大溶胶粒度从而增大薄膜的粗糙度,提高薄膜的疏水性。表面修饰效果受修饰方式和SiO2粒径影响,粒径较小时有利于溶胶内修饰,粒径较大时有利于对薄膜修饰。经过表面修饰剂(HMDS)的气氛处理得到了接触角为152°的超疏水薄膜,而且相比溶胶内修饰可以减小薄膜透光率的损失。     

Plasma-induced grafting of polydimethylsiloxane onto polyurethane surface: Characterization and in vitro assay

Plasma-induced grafting of polydimethylsiloxane (PDMS) onto the surface of polyurethane (PU) film. The virgin, plasma treated, and PDMS grafted PU films were characterized by means of attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, water drop contact angle measurements, and scanning electron microscopy (SEM). The ATR-FTIR spectrogram of the grafted film showed the new characteristic peaks of PDMS. These grafted surfaces exhibited higher hydrophobicity and homogenous morphology. In vitro cell culture study showed that modified surfaces as well as virgin film were compatible with fibroblast cells. The formation of graft polymers combines the biostability of silicone with excellent physical and mechanical properties of PU.     

Investigation of covalently colored polyurethane latexes based on novel anthraquinone polyurethane chain extenders

Novel red and yellow polyurethane (PU) chain extenders with one anthraquinone chromophore and two hydroxyls were synthesized, and then used to fabricate covalently colored PU latexes with pendent chromophores on the PU backbone. The chemical structures of the chain extenders were characterized by ¹H-NMR and FTIR, and the properties of PU latexes and their films were investigated by UV-Vis absorption spectra, particle size analysis, FTIR, Soxhlet's extraction and xenon arc aging testing. Results showed that the covalently colored PUs had the same UV-Vis absorption behavior as the corresponding chain extenders, and amount of the chain extenders had no obvious influence on the latex preparation process and the resulted latex colloidal properties. Compared with the corresponding non-covalently colored PU latex films, both the light fastness and the solvent fastness of the covalently colored PU latex films were significantly enhanced by the covalent incorporation of chromophores with PU matrix.     

聚氨酯/聚丙烯酸酯复合乳液粒子热力学平衡形态预测

以水性聚氨酯分散液为种子采用无皂乳液聚合新技术合成出了具有核壳结构的聚氨酯/聚丙烯酸酯（PU/PA）复合聚合物乳液。采用界面张力简化计算方法计算了聚合物与聚合物之间以及聚合物和水之间的界面张力,通过界面自由能变化最小的热力学判据对合成的复合乳液粒子的热力学平衡形态进行了预测。并利用透射电子显微镜观察和用接触角法测定的膜的表面极性对其进行了证实。结果表明：界面自由能变化的最小判据可以推广到PU/PA 体系,本文给出的界面张力的简化计算方法是可行的。     

提高聚氨酯表面硅橡胶涂层粘接性研究

利用表面处理并借助硅烷偶联剂大幅提高了聚氨酯/硅橡胶(PU/SR)的界面粘接性.利用红外光谱、水接触角以及表面元素分析对PU表面处理效果及偶联剂的反应效果进行检测,利用扫描电镜对材料的表面形貌及界面情况进行观察.并对不同方法得到的PU/SR界面进行剪切和振动疲劳测试以考察其粘接效果并进行比较.结果表明,经过硫酸短时处理过的PU表面生成大量羟基,使得亲水性提高,并大大增强了端异氰酸酯基硅烷偶联剂与PU的接枝反应效果.当室温缩合固化的硅橡胶预聚体涂覆到其表面后,以化学键联接在PU表面的硅烷偶联剂又可以与硅橡胶一起缩合,从而有效的提高了PU/SR的界面粘接性.     

软段对水性聚氨酯结构与性能的影响

以低聚物多元醇、异氟尔酮二异氰酸酯(IPDI)、亲水单体二羟甲基丙酸(DMPA),乙二胺为主要原料,制备了一组不同组成的聚氨酯乳液。通过粘度测定、粒度分析、力学性能和耐水性能测试、原子力显微镜(AFM)分析,研究了软段类型、软段分子量对乳液及其胶膜性能的影响。结果表明,分子结构规整、易结晶的软段合成的聚氨酯树脂力学性能和耐水性能都较好,对聚己二酸酯而言,分子量减小,其合成的水性聚氨酯拉伸强度提高,耐水性能却有很大程度的下降。     

Increasing the Hydrophobicity of a PP Film Using a Helium/CF<Subscript>4</Subscript> DBD Treatment at Atmospheric Pressure

Plasma surface modification is widely used to tailor the surface properties of polymeric materials. Most treatments are performed using low pressure plasma systems, but recently, atmospheric dielectric barrier discharges (DBDs) have appeared as interesting alternatives. Therefore, in this paper, an atmospheric He + CF₄ DBD is used to increase the hydrophobicity of a polypropylene (PP) film. The surface characterization of the PP film is performed using contact angle measurements, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Results show that the hydrophobic properties of the polymer films are greatly enhanced after plasma treatment as evidenced by an increased contact angle. The incorporation of fluorine on the surface is significant (45 at%), demonstrating the ability of the used DBD set-up to generate fluorine-containing functional groups on the PP surface.     

Thermal and pH dual responsive polyurethane/2-(diisopropylamino)ethyl methacrylate hybrids: Synthesis,characterization, and swelling behavior

This article describes the synthesis and characterization of stimuli-sensitive hybrid films using 2-(diisopropylamino)ethyl methacrylate (DPA), and a polyurethane (PU) base on isophorone diisocyanate. Hybrid films with different amounts of DPA present good film and physicochemical properties. Characterization techniques such as Fourier transform infrared, UV–visible, modulate differential scanning calorimetry, and thermogravimetric analysis reveal chemical interactions between PU and DPA groups. Swelling behavior of films shows a dependence on DPA content, pH, and temperature and different mechanisms of water uptake in response to pH and temperature variations. Hybrid systems would allow controlling water absorption not only through pH or temperature but also from the chosen PU/DPA proportion.     

The effect of attached tetracycline and hydrophilic groups on the enhancement of antibacterial effectiveness and low temperature flexibility of polyurethane

Tetracycline was chemically attached to polyurethane (PU) to enhance its antimicrobial activity, and a carboxyl group or polyol was also attached to PU to enhance the hydrophilicity. The attached groups affected cross‐linking, viscosity of PU solution, glass transition of soft segment, breaking tensile stress, reliable shape recovery capability, flexibility at very low temperature, surface hydrophilicity, and antibacterial effectiveness. The glass transition temperature could go up from ?67.5°C for unmodified PU to ?48.8°C due to the attached tetracycline. The attachment of tetracycline boosted breaking tensile stress and shape recovery by 345% and 186%, respectively, relative to unmodified PU. The attached carboxyl group and polyol improved the hydrophilicity as confirmed by water swelling and water contact angle data. Finally, PU samples with the attached tetracycline demonstrated excellent flexibility at freezing temperature compared with ordinary PU and absolutely inhibited the bacterial growth of S. aureus and K. pneumoniae on PU.     

Controlled loading and release of methylene blue from LbL polyurethane/poly(acrylic acid) film

The layer‐by‐layer (LbL) assembled multilayer films are widely used in the biomedical field for the controlled drug delivery. Here, multilayer films were assembled by LbL technique through alternating deposition of cationic polyurethane (PU) and poly(acrylic acid) (PAA) on glass slides. Methylene blue (MB) was used as a model drug to investigate the loading and release ability of the prepared multilayer film. The results showed that the loading rate and loading amount of MB were greatly influenced by pH value of the dye solution, and the release rate of MB was controlled both by ionic strength and pH value of immersing solution. The result also indicated that the film had a good reversibility of drug loading and release. It suggested that the PU/PAA multilayer film had potential applications in drug delivery and controlled release. Copyright © 2011 John Wiley & Sons, Ltd.