Synthesis and surface mobility of segmented polyurethanes with fluorinated side chains attached to hard blocks

Novel polyurethanes with fluorinated side chains attached to hard blocks were synthesized and characterized by NMR, mass spectroscopy, DSC and gel permeation chromatography (GPC). A unique chain extender, 3-(2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-pentadecafluoro-octyloxy)-propane-1,2-diol (PFOPDOL) was prepared from 3-(2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-pentadecafluoro-octyloxymethyl)-oxirane (PDFOMO) by reacting it with diluted perchloric acid. Poly(ether urethane)s and poly(carbonate urethane)s containing various amounts of the chain extender with fluorinated side chains were then synthesized using methylenebis(phenylene isocyanate) (MDI), polytetramethyleneoxide (PTMO), poly(1,6-hexyl-1,5-pentylcarbonate) diol (PHPCD), 1,4-butandiol (BDO) and PFOPDOL. Mechanical properties of the polyurethanes were characterized by Instron. Surface properties were characterized by X-ray photoelectron spectroscopy (XPS) and contact angle measurements. Results from GPC and Instron studies indicated that fluorinated polyurethanes with high molecular weights and good mechanical properties were obtained. Results from XPS and contact angle studies indicated that the surface of fluorinated polyurethanes were very nonpolar due to migration of fluorinated side chains to the surface.     

Synthesis and properties of novel fluoroalkyl end‐capped oligomers containing phosphorus segments

New fluoroalkyl end‐capped oligomers containing pendant phosphoric acid groups wereprepared by the reactions of the corresponding monomer with fluoroalkanoyl peroxides. It was demonstrated that not only strong aggregations of fluoroalkyl segments but also hydrogen bonding could interact synergistically to form the highly viscoelastic fluids (gel‐like fluids) in aqueous solutions of these new fluoroalkyl end‐capped oligomers containing pendant phosphoric acid groups. Furthermore, these oligomers were able to reduce the surface tension of water effectively to exhibit a clear breakpoint resembling a CMC, and the modified stainless‐steel surface treated with these oligomers was shown to possess an excellent property imparted by fluorine. More interestingly, these oligomers were found to be potent and selective inhibitors against HIV‐1 replication in vitro. New fluoroalkyl end‐capped phosphonic acid and phosphonate oligomers were also prepared by the reactions of the corresponding phosphonic acid and phosphonate monomers, respectively, by the use of fluoroalkanoyl peroxides. These new fluoroalkyl end‐capped phosphonic acid and phosphonate oligomers were found to have a higher solubility in not only water but also in common organic solvents than that of the corresponding fluorinated oligomers containing pendant phosphoric acid groups, and these new oligomers were able to reduce the surface tension of these solvents quite effectively. Thus, these oligomers are expected to develop as new fluorinated oligosurfactants. Moreover, the modified poly(methyl methacrylate) surface treated with these phosphonate oligomers was clarified to exhibit a good oil‐repellency imparted by fluorine. In addition, fluoroalkyl end‐capped phosphonate homo‐ and cooligomers were found to form monomolecular films at the air–water interface. Therefore, these fluorinated oligomers are suggested to have high potential for new functional materials through not only their excellent properties imparted by both fluorine and phosphorus, but also through their biological properties. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 228–245, 2001     

Synthesis of a water‐soluble fullerene derivative nanoball and its biological activity

A novel fullerene–acrylamide copolymer was synthesized via radical polymerization. It is soluble in polar solvents such as water and dimethyl sulfoxide. The product was characterized by FTIR, UV–vis, and GPC. TEM analysis showed that the average particle diameter was about 46 nm. The in vitro antitumor activity of the fullerene–acrylamide derivatives was tested, and the results showed that the novel fullerene–acrylamide derivatives exhibited better antitumor activity in vitro against bone tumor cells. The cytotoxicity against the tumor cell mechanism of the fullerene copolymer nanoball was studied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

Synthesis and applications of silicone oil–soluble fluoroalkyl end‐capped cooligomers

Fluoroalkyl end‐capped cooligomers containing polydimethylsiloxane and polyoxyethylene segments were prepared under very mild conditions by the cooligomerizations of fluoroalkanoyl peroxides with methacrylate monomers containing the corresponding segments and comonomers such as dimethylacrylamide and acryloylmorpholine. These obtained fluorinated cooligomers exhibited amphipathic characteristics and became soluble in water and common organic solvents. In particular interest, fluoroalkyl end‐capped cooligomers containing polyoxyethylene units were soluble not only in poly(methylphenylsiloxane) (silicone oil) but also in water, including common organic solvents except for hexane. Additionally, these fluorinated cooligomers were able to reduce the surface tension of water and m‐xylene quite effectively, to around 15 and 20 mN/m levels, respectively. In these fluorinated cooligomers, fluoroalkyl end‐capped acryloylmorpholine cooligomers containing polyoxyethylene segments were applicable as a novel emulsifying agent against water and silicone oil. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1467–1476, 2005     

Synthesis and properties of novel perylenebisimide-cored dendrimers

A group of perylenebisimide-cored dendrimers with polyphenylene dendrons at four bay positions were synthesized and characterized. The electron-deficient pentafluorophenyl or cyano groups were grafted at the dendrimer surface with the aim to further increase the n-type features of the resulted dendrimers. The electrochemical and optical properties were investigated. All the dendrimers show good solubility and film-forming properties, high EA values of 3.8-3.9 eV, and high fluorescent quantum yields. All these merits indicate that they are potential multifunctional materials for application in optoelectronic devices such as solar cells or organic light-emitting devices.     

Preparation and applications of novel fluoroalkyl end-capped acrylic acid oligomers/silica nanocomposites-encapsulated fullerenes

Fluoroalkyl end-capped acrylic acid oligomers/fullerenes nanocomposites reacted smoothly with tetraethoxysilane (TEOS) and silica nanoparticles under alkaline conditions to give fluoroalkyl end-capped oligomers/silica composites-encapsulated fullerenes. Interestingly, these isolated fluorinated composites were found to afford nanometer size-controlled colloidal particles with a good dispersibility in a variety of organic solvents including water. More interestingly, these fluorinated silica nanocomposites-encapsulated fullerenes were applied to a new type of surface modification agent, and these nanocomposites were able to disperse well above the poly(methyl methacrylate) films to exhibit not only surface active property imparted by fluorine but also a unique characteristic related to fullerenes in the nanocomposites on the surface, effectively.     

Synthesis and surface properties of amphiphilic fluorine-containing diblock copolymers

Amphiphilic diblock copolymers (DCs) of 2,3,4,5,6-pentafluorostyrene (PFS) and 2-hydroxyethyl methacrylate (HEMA) of different composition and molecular weights were prepared by two-step reversible addition–fragmentation chain transfer (RAFT) polymerization and first used for preparation of superhydrophobic coatings for cotton/polyester fabrics. The transition from hydrophobic to superhydrophobic coatings is controlled by the ratio between poly(2,3,4,5,6-pentafluorostyrene) (PPFS) block and poly(2-hydroxyethyl methacrylate) (PHEMA) block lengths (P_n^PFS/P_n^HEMA). The increase in P_n^PFS/P_n^HEMA is accompanied by a significant increase in water (θ^Н₂^О) and diiodomethane (θ^CH₂^I₂) contact angles, which reach the plateau at P_n^PFS/P_n^HEMA = 3.5 and remains almost constant up to P_n^PFS/P_n^HEMA = 6.2. Surface modification of the cotton/polyester fabric with the DC having P_n^PFS/P_n^HEMA = 6.2 produced superhydrophobic surface with θ^Н₂^О = 158 ± 4° and contact angle hysteresis CAH = 5 ± 2°, and θ^CH₂^I₂ = 107 ± 3°.     

新型对称性两亲含硅聚合物的合成与界面性能

基于原子转移自由基聚合(ATRP)机理,以二甲基一氯硅烷封端的烯丙基-聚乙二醇为起始剂,甲基丙烯酸乙酯(EMA)为单体,通过控制反应温度,合成了一系列聚合度(DP_(NMR))分别为0. 74,1. 67和3. 07的新型对称性两亲含硅共聚物(PEMA-b-Si-PEG-Si-b-PEMA),并评价了该共聚物在氯仿/水界面的界面活性和吸附行为。结果表明:该类聚合物可以有效降低氯仿/水界面张力,具有最短PEMA链的聚合物可将氯仿/水界面张力从32 m N/m降低至约23 m N/m。动态界面张力分析表明:低浓度的共聚物在吸附的初始阶段符合扩散控制,且较短的PEMA链段有利于产生较快的扩散速率。平衡界面张力分析表明:随着界面浓度的增加,共聚物将表现出多种吸附状态,其吸附状态的数量以及聚合物在界面的偏摩尔面积将随着PEMA链长度的增加而增加。     

Synthesis,surface, thermodynamic properties and Biological activity of dimethylaminopropylamine surfactants

The chemical structure of the prepared cationic surfactants which formed through condensation reaction between dimethylaminopropylamine (DMAPA) and butyraldehyde then quaternized by three fatty alkyl bromide was confirmed by FTIR, ¹HNMR and mass spectroscopy. The chemical structure of prepared compounds has an effect on surface properties. By increasing the hydrophobic chain length, the values of CMC and Г_max decrease while A_min value was increased. The Thermodynamic parameters showed that adsorption and micellization processes are spontaneous. It is clear that the prepared cationic surfactants tend to adsorb at surface, then it aggregate to form micelle. The prepared surfactants showed good biological activity against Gram-positive and negative bacteria and fungi. The prepared cationic surfactant showed aggressive effect on the sulfate reducing bacteria growth.     

Synthesis and properties of novel fluoroalkyl end‐capped oligomers containing silsesquioxane segments

Fluoroalkyl end‐capped homo‐ and co‐ oligomers containing silsesquioxane segments were prepared by the reactions of fluoroalkanoyl peroxides with the corresponding methacrylate monomer‐bearing silsesquioxane unit (Si‐MMA) and comonomers such as N,N‐dimethylacrylamide (DMAA) and acrylic acid (ACA). These new fluorinated Si‐MMA oligomers were easily soluble in various organic solvents and were able to reduce the surface tension of m‐xylene effectively. The modified poly(methyl methacrylate) [PMMA] and glass surface treated with fluorinated Si‐MMA homo‐oligomers exhibited a strong oleophobicity, although these fluorinated oligomers possess high oleophilic silsesquioxane segments. In contrast, the modified PMMA surface treated with fluorinated Si‐MMA–DMAA cooligomers exhibited a good hydrophilicity with a strong oleophobicity. In a series of fluorinated Si‐MMA oligomers, fluorinated Si‐MMA homo‐oligomers had a relatively high thermal stability. Therefore, these fluoroalkyl end‐capped Si‐MMA oligomers are suggested to have high potential for new functional materials through their unique properties such as a high solubility and surface active properties. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3486–3493, 2002     

Preparation and characterization of a novel composite based on hyperbranched polysilane and fullerene

Conjugated polymers doped with fullerenes have shown promising application in photovoltaic cells, in which photoinduced charge transfer takes place. Here, we report a novel composite that was prepared by in situ polymerization of σ‐conjugated hyperbranched polysilane in the presence of fullerene. Both of the hyperbranched polysilane and fullerene have 3D structures, which are propitious to preparing materials with interpenetrating structure. The resulting composite has good solubility in common organic solvents and the UV spectrum edge suggests a low bandgap. Photoluminescence quenching in the composite is shown by the PL spectra and is also observed from the fluorescence microscopy images, which may be ascribed to the PCT from the hyperbranched polysilane to the fullerene. The composite was also characterized by GPC, FTIR, NMR, XRD, and TGA. Through further discussion, there may be π‐π stacking between hyperbranched polysilane and fullerene, which enhances the photoinduced charge transfer. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Surface Activity,Aggregation, and Wetting Behavior of Sodium P-Perfluorononenyloxy Benzene Sulfonate

The physicochemical properties of sodium p-perfluorononenyloxy benzene sulfonate (OBS) in aqueous solution were investigated. Compared to linear alkylbenzene sulfonate (LAS), OBS has a lower critical micelle concentration (CMC) and a low surface tension at the CMC. At the same concentration, OBS shows lower dynamic surface tension than LAS indicating faster wetting kinetics. In aqueous solution, OBS forms large spherical vesicles above the CMC. OBS shows excellent dynamic wetting properties on low-energy surfaces. The superior properties of OBS make it ideal for use in many industry fields.     

Synthesis and cationic photopolymerization of a new fluorinated oxetane monomer

A new fluorinated oxetane monomer (FOX) was prepared using a fluorinated alcohol by phase transfer catalysis in a Williamson ether synthesis. The new fluorinated monomer was used in cationic photopolymerization as comonomer of 3,3′-[oxydi(methylene)]bis(3-ethyloxetane). The presence of the FOX monomer induces a decrease of the glass transition temperature, thermal stabilization and an increase of the final oxetane group conversion. Completely hydrophobic surfaces were obtained with a selective enrichment of the fluorinated comonomer, as confirmed by contact angle and XPS analysis.     

Characterization,surface properties and biological activity of some synthesized anionic surfactants

In this study, esterification reaction between four different fatty alcohols (octyl, dodecyl, hexdecyl and octadecyl alcohol) and phosphoric acid was performed. The produced compound was reacted with polyethylene glycol-400. Then, the reaction product was quenched using sodium hydroxide to form the desired anionic gemini surfactants. The chemical structures of the synthesized surfactants were recognized by FT-IR and ¹H NMR spectroscopy. The synthesized surfactants showed higher surface activity. The emulsion stability measurements showed the applicability of these surfactants as emulsifying agents. The foaming power measurements showed the synthesized surfactants have low ability to foam formation. The thermodynamic parameters showed their tendency toward adsorption at the interfaces and also micellization in the bulk of their solutions. The studied surfactants were evaluated as antimicrobial agents against pathogenic bacteria using inhibition zone diameters. The synthesized surfactants showed good antimicrobial activities against the tested microorganisms including Gram positive, Gram negative as well as fungi. The promising inhibition efficiency of these compounds against the pathogenic bacteria facilitates them to be applicable in the petroleum field as new categories of biocides.     

一种新型两亲性聚合物的合成研究

合成了一种新型的两亲性共聚物(丙烯酰胺/醋酸乙烯酯/丙烯酸丁酯,AM/VAc/BA),探讨了在该共聚物合成过程中AM用量和VAc与BA的配比对其表面张力、离心稳定性、乳化性及发泡力的影响,并对该三元共聚物P(AM/VAc/BA)的结构进行表征。结果表明,傅立叶红外光谱(FT-IR)分析在1 680 cm-1~1 620 cm-1处无C=C伸缩振动吸收峰出现,说明体系反应较彻底;差示扫描量热(DSC)分析得共聚物的玻璃化转变温度为37.6℃。     

新型双亲性交替共聚物的合成及其性能研究

以N-正辛基马来酰亚胺(OPD)与对氯甲基苯乙烯(CMS)为聚合单体,采用自由基聚合法制备了交替聚合物P(CMS-alt-OPD),用三甲胺将聚合物中的苄氯进行季铵化得到新型季铵盐型双亲性交替聚合物P(TMVPMA-alt-OPD)。用傅立叶变换红外光谱(FTIR)、凝胶渗透色谱(GPC)、核磁共振(1H NMR)对P(CMS-alt-OPD)和P(TMVPMA-alt-OPD)进行了结构表征,并研究了不同反离子条件下该聚合物的自组装行为与乳化性能。利用纳米粒度及Zeta电位分析仪和透射电镜(TEM)对聚合物胶束进行了形态表征,研究表明,反离子为乳酸根时,聚合物胶束粒径(267.9 nm)小于反离子为氯离子的聚合物胶束(420.6 nm),并具有更好的乳化性能。     

Synthesis of amphiphilic copolymers having capability as emulsifiers and their surface chemical properties

Some comblike terpolymers composed of methyl methacrylate (MMA), methoxypolyethyleneglycol methacrylate (MPEGMA) as a hydrophilic component, and methoxypolypropyleneglycol methacrylate (MPPGMA) as a hydrophobic component were synthesized by both living radical photopolymerization and ordinary radical polymerization. Since these terpolymers showed a high surface activity, it was suggested that they could be utilized as good polymeric emulsifiers. The polymeric emulsions containing these emulsifiers also showed comparatively good emulsion and mechanical properties as an adhesive. From these facts, it was found that these terpolymers had almost the same emulsification capability as commercially available low molecular weight emulsifiers. Conversely, a difference in surface tension behavior of these terpolymers could be observed. We think that it was due to the chain arrangements (random or block sequence) of the terpolymer. Amphiphilic copolymer Emulsion polymerization Polymeric emulsifier Micelle formation     

Synthesis and characterization of novel fluorinated azopolyamides

Summary  Novel soluble fluorinated azopolyamides 4a-d were synthesized by reacting 2-trifluoromethyl-4,4’-diaminodiphenyl ether 2 with various azodibenzoyl chlorides 3a-d using the low temperature solution polycondensation technique. The fluorinated diamine 2 was prepared through the nucleophilic substitution reaction of 4-nitrophenol and 2-chloro-5-nitrobenzotrifluoride via catalytic reduction catalytic reduction with hydrazine and Pd/C. All of the fluorinated azopolyamides exhibited excellent solubility at room temperature in strong polar solvents such as N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO) and N-methyl-pyrrolidinone (NMP). Inherent viscosities of the azopolyamides were found to range from 0.85 to 1.35 dl/g, and those azopolyamides could be cast into flexible and tough films from DMAc solutions. The azopolyamides showed that the glass transition temperatures (T_g) were between 231 and 259^oC, and the char yields of all the azopolyamides except for 4d at 800^oC in nitrogen atmosphere were above 47%. Furthermore, all the azopolyamides exhibited thermal and photochromic properties.     

两亲性无规共聚物MAA-SMA-PEGMA的表面活性研究

利用功能性单体甲基丙烯酸(MAA)、甲基丙烯酸十八烷基酯(SMA)和聚乙二醇甲基丙烯酸酯(PEG-MA)通过自由基共聚,合成了两亲性共聚物Poly(MAA-SMA-PEGMA)。研究了其结构、临界胶束浓度(CMC)和表面张力,探讨了由共聚物与低分子表面活性剂组成的复配体系。结果表明高低分子表面活性剂复配体系在质量比为5∶5后,体系的表面张力和临界胶束浓度都有所降低,接近于低分子表面活性剂。     

Tailored surface properties of semi-fluorinated block copolymers by electrospinning

Diblock copolymers based on polystyrene (PS) macroinitiators and four different fluorinated monomers (perfluorooctyl ethyl methacrylate (FMA), pentafluorostyrene (FS), perfluorooctyl-ethylene oxymethyl styrene (EMS), 2,3,5,6-tetrafluoro-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecaoxy)styrene (FSF)) were synthesized via atom transfer radical polymerization (ATRP). The lengths of the PS and fluorinated blocks were altered and the surface and self-assembling properties of the polymers were compared with respect to the fluorinated monomer used and the fluorine content. The surface properties, contact angles and surface tension, were enhanced by the existence of the CF₃ groups at the end of the alkyl chains compared with poly(pentafluorostyrene). Hydrophobicity of the surfaces was further enhanced by electrospinning the polymer solutions, which yielded superhydrophobic surfaces with water contact angles >150° for polymers having CF₃ groups.