PAM/SA/CNFs复合水凝胶的制备与性能研究

通过溶液交联聚合法制备了聚丙烯酰胺(PAM)/海藻酸钠(SA)/纤维素纳米纤维(CNFs)半互穿网络结构复合水凝胶。研究了不同添加量的CNFs对SA/PAM/CNFs复合水凝胶的溶胀性能和力学性能的影响;并测定了该复合水凝胶对亚甲基蓝染料的吸附性能。结果表明:当CNFs添加量为0.1ω/%时,复合水凝胶对亚甲基蓝染料的吸附效果最好,且平衡溶胀度最大为9.47,复合水凝胶压缩应力达到114.64 kPa。     

聚氨酯预聚体/PAM/NBR复合吸水膨胀橡胶的研究

通过共混NBR,聚醚型聚氨酯预聚体和聚丙烯酰胺(PAM)树脂制备了吸水膨胀橡胶材料(WSR),研究了聚氨酯预聚体/PAM配比对吸水膨胀橡胶物理机械性能和吸水性能的影响。结果表明,当聚氨酯预聚体/PAM配比为15/45时,吸水膨胀橡胶的吸水膨胀率较大,质量损失较小,反复吸水性能优异,吸水速率远远大于单用PAM时的吸水速率,综合物理机械性能较好。SEM分析表明,加入聚氨酯预聚体后PAM树脂颗粒与NBR界面间的结合状况有所改善。     

纳米硅/聚丙烯酰胺水凝胶的制备及性能研究

通过光催化方法制备了纳米硅(F-SiNPs),再以丙烯酰胺(AM)为单体、过硫酸铵为引发剂、N,N-亚甲基双丙烯酰胺为交联剂,采用原位聚合法在纳米硅水溶液中制备了F-SiNPs/聚丙烯酰胺(F-SiNPs/PAM)复合水凝胶,并采用激光粒度分析仪(DLS)、场发射透射电子显微镜(FE-TEM)、红外光谱(FT-IR)、X射线光电子能谱(XPS)、场发射扫描电子显微镜(SEM)、紫外荧光光谱(UV-PL)等手段对复合水凝胶的结构与性能进行表征。结果表明,成功地制备了F-SiNPs/PAM复合水凝胶,且F-SiNPs/PAM复合水凝胶同时具有荧光特性与pH敏感性。     

耐超高矿化度遇水膨胀橡胶的制备及性能

用甲基丙烯酸羟乙酯(HEMA)对吸水膨胀聚氨酯(PU)预聚体进行封端,制备出PU聚合物活性树脂。以丁腈橡胶(NBR)为基体,将聚丙烯酰胺(PAM)树脂和PU聚合物活性树脂共混,实现PU聚合物活性树脂与NBR大分子化学接枝交联,制备出新型高耐盐型遇水膨胀橡胶(WSR)。研究了超高矿化度下,PAM用量对材料力学性能和吸水膨胀倍率的影响。结果表明,PAM用量增加,WSR吸水膨胀倍率提高,但是力学性能降低;在20万超高矿化度下,浸泡400h后,WSR最大膨胀倍率稳定在2.7倍左右,表面无析出现象,表现出优异的耐盐性。     

羧甲基壳聚糖/聚(N-异丙基丙烯酰胺)半互穿网络水凝胶的制备及吸附重金属离子

以N-异丙基丙烯酰胺和羧甲基壳聚糖(CMCS)为原料成功制备了羧甲基壳聚糖/聚(N-异丙基丙烯酰胺)半互穿网络水凝胶,通过扫描电镜(SEM)﹑测溶胀比对凝胶性能进行了表征。考察了羧甲基壳聚糖对于凝胶内部微观结构的影响及其对Fe3+吸附性能的变化。发现随着CMCS用量的增加,凝胶内部结构的孔状网络结构更为明显,水凝胶对Fe3+离子吸附能力增强。     

聚丙烯酰胺/凹凸棒粘土复合吸附材料的研究

采用溶液聚合法在硅烷化凹凸棒粘土(OATP)表面接枝丙烯酰胺(AM),制备聚丙烯酰胺/凹凸棒粘土(PAM/ATP)复合吸附材料。通过考察PAM/ATP复合吸附材料对汞离子吸附性能的影响,对其制备条件进行了优化。采用热重/差示扫描量热(TG/DSC)和傅里叶变换红外光谱(FT-IR)对PAM/ATP进行了表征。结果表明,当AM质量分数(相对OATP质量,下同)为30%,聚合反应时间为6h,引发剂质量分数为3.0%,反应温度为80℃时,制备的PMA/ATP对汞离子的最大吸附容量可达到135.5mg·g-1。TG/DSC分析表明,PAM/ATP的DSC曲线在345℃出现一有机物分解吸热峰,且PAM/ATP的热失重率(18.0%)明显高于ATP(5.0%)和OATP(7.0%);FT-IR分析表明,PAM/ATP在1604cm-1(-NH2或-NH的弯曲振动)和3190cm-1(-NH2或-NH伸缩振动)及1671cm-1(-C=O伸缩振动)有新的吸收峰出现,表明PAM成功接枝于OATP表面。与ATP、OATP相比,PAM/ATP对Hg2+离子的吸附容量增大了6倍以上。     

铁盐/聚氨酯复合多孔膜的制备及其吸附性能研究

以聚氨酯(PU)和铁盐化合物为主要原料,通过非溶剂诱导相分离技术(NIPS)和填充改性技术,成功制备了一系列的聚氨酯基多孔复合膜。结果表明,铁盐成功填充到聚氨酯膜中,改性后的聚氨酯膜的染料吸附性能有一定提升;Fe/PU复合膜对刚果红(CR)的吸附量从18.33 mg/m~2提升到235.05 mg/m~2,对甲基橙(MO)的吸附量从5.00 mg/m~2提升到366.16 mg/m~2,且对MO吸附符合拟二级吸附动力学(R~2=0.99)。复合膜的吸附性能随着初始染料浓度的增加而提高,在三次循环吸附下均能保持较高吸附性能。     

负载白芨多糖的PU/PAM双网络水凝胶的制备与性能

采用聚乙二醇、Ymer N120、聚丙二醇和异佛尔酮二异氰酸酯为原料,以三乙醇胺作交联剂合成聚氨酯(PU)预聚物,浸入白芨多糖(BSP)和丙烯酰胺(AM)混合溶液,通过自由基聚合制备了负载BSP的PU/PAM双网络水凝胶.采用FTIR、SEM对水凝胶的结构和形貌进行了表征,通过拉力试验机和生物实验对其力学性能和生物性能进行了测试.结果表明,当三乙醇胺用量为多元醇物质的量的60％时,双网络水凝胶具有高溶胀率(256％)的同时保持一定的拉伸强度(1.9 MPa)和高压缩强度(22.7 MPa).双网络水凝胶具有抗菌抗氧化作用,其中,双网络水凝胶对大肠杆菌和金黄色葡萄球菌的抑菌带宽度分别为0.5～4.0和0.5～3.5 mm,羟基自由基清除率最高为28％;溶血率低于5％,细胞存活率最高达101.3％±3.6％,表明双网络水凝胶具有良好的生物相容性.     

高吸油软质聚氨酯泡沫材料的制备及其吸油性能研究

以聚环氧丙烷三醇(N330)、聚环氧乙烷二醇(N220)、聚四氢呋喃二醇(PTMG)、三乙烯二胺、辛酸亚锡、有机硅匀泡剂和甲苯二异氰酸酯(TDI)等为原料,采用一步法全水发泡工艺,制备了一种疏水性高吸油软质聚氨酯泡沫(PU)。研究了PTMG的用量对PU的吸油性能、孔结构、密度以及拉伸强度的影响,并考察了这类泡沫材料的再生循环性能。结果表明,随着PTMG用量的增加,PU的孔径减小,拉伸强度逐渐提高,PU对油品的吸附倍率先增加后减小,最大吸附倍率分别为:柴油18.9 g/g、二甲苯34.9 g/g、乙酸乙酯32.8 g/g、四氯化碳56.9 g/g。采用外力挤压法可有效地去除吸附油品以达到PU再生循环利用的目的,且重复使用12次后,PU对柴油的脱附效率仍高于98%,吸附倍率稳定在16.2 g/g。     

有机/无机复合自修复水凝胶的制备及对Cu~(2+)吸附性能研究

以纳米粘土为交联剂制备了具有自修复性能的聚丙烯酰胺/海藻酸钠/粘土(PAM/SA/Clay)复合水凝胶。探讨了单体与粘土配比、单体与海藻酸钠配比等参数对水凝胶成胶性能的影响。重点对该复合水凝胶的自修复机理、自修复性能及对重金属(Cu~(2+))吸附性能进行评价。结果表明,该复合水凝胶中粘土与单体配比在1∶1时有良好的成胶性能;水凝胶的溶胀性能随粘土含量的增加而下降,最大溶胀率为20.3622g·g~(-1);随着海藻酸钠含量的升高,凝胶的重金属吸附性能提高,单体、粘土及海藻酸钠用量比为1∶1∶0.2时,24h吸附量最大为1.4300×10~(-5)mol·g~(-1);合成的水凝胶在室温下无需任何外加条件,24h即可实现损伤断面的良好的修复。     

Adsorption and recognition of protein molecular imprinted calcium alginate/polyacrylamide hydrogel film with good regeneration performance and high toughness

Protein imprinted calcium alginate/polyacrylamide hydrogel film (CA/PAM MIP) with high toughness was prepared using bovine serum albumin (BSA) as template molecule, sodium alginate and acrylamide as functional monomers, N,N′-methylenebisacrylamide (MBAA) as the covalent cross-linker and CaCl₂ as the ionic cross-linker via UV radiation-reduced polymerization. Factors affecting the adsorption capacity and imprinting efficiency of the BSA-imprinted CA/PAM hydrogel films were investigated, such as ratio of polyacrylamide/sodium alginate, film thickness, MBAA concentration and CaCl₂ concentration. Results showed that the CA/PAM MIP exhibited an obvious improvement in terms of adsorption capacity for BSA compared with non-imprinted polymer (NIP). The adsorption capacity of MIP for BSA reached 22.49 mg/g, which was 2.7 times higher than NIP. The regeneration property of the BSA-imprinted CA/PAM hydrogel was distinctly improved and the imprinting efficiency of CA/PAM MIP maintained 77.95% of the initial value after five repetitions. Single and binary proteins rebinding indicated that the CA/PAM MIP exhibited good recognition performance. Cell culture experiments showed CA/PAM MIP was more suitable for cell culture than CA/PAM NIP. The residual sodium dodecyl sulfate (SDS) in the elution process leaded to the death of mouse fibroblast cells (L929) after 3 days. A moderate elution solution without residue eluent should be used to prepare MIP for cell culture.     

Novel floating photocatalysts based on polyurethane composite foams modified with silver/titanium dioxide/graphene ternary nanoparticles for the visible‐light‐mediated remediation of diesel‐polluted surface water

Photocatalyst loading on a floating substitute is accepted as a promising method for the remediation of diesel‐polluted surface water. Therefore, novel photocatalysts based on polyurethane foams modified with silver/titanium dioxide/graphene ternary nanoparticles (PU–Ag/P25/G) were synthesized and investigated. Scanning electron microscopy, energy‐dispersive X‐ray spectrometry, X‐ray diffraction, Fourier transform infrared spectroscopy, and UV–visible spectroscopy showed the coexistence of Ag, Degussa P25 (P25), and graphene and the nanoscale dispersion of nanoparticles in the matrix and on the surface of the polyurethane (PU) foam. The diesel adsorption capacity of the photocatalyst reached 96 g/g. The maximum diesel degradation was found to be 76% in a period of 16 h. Compared with polyurethane‐foam‐supported P25/graphene (PU–P25/G) and polyurethane‐foam‐supported P25 (PU–P25), all of the adsorption isotherm and degradation kinetics followed the order PU–Ag/P25/G > PU–P25/G > PU–P25 > PU; this was due to the loading of different nanoparticles. Moreover, the degradation efficiency was reduced only 5% after five consecutive reactions; this showed good stability and reusability of the photocatalyst for surface water restoration. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43400.     

Removal of Some Heavy Metal Ions Using Grafted Polyurethane Foam

Polyurethane (PU) was modified by grafting a mixture of two monomers acrylonitrile/acrylic acid (AN/AAc) by gamma irradiation method. Effects of various parameters such as, concentration of comonomer composition, grafting yield, gamma irradiation doses, dose rates and pH of adsorbent on the adsorption capacity were studied. Characterizations of the grafted polyurethane (PU-g-AN/AAc) were investigated using infrared (IR) spectroscopic analysis, X-ray diffraction (XRD) and scanning electron microscope (SEM). Moreover, the adsorption capacities of some heavy metals such as, Zn(II), Fe(II), Ca(II), Ni(II), Cu(II) and Pb(II) onto PU-foam and PU-g-AN/AAc were studied. The efficiency of such grafted polyurethane foams for uptaking different previous metal ions was determined and compared with that of natural granular activated carbon (GAC). The uptaking of metal ions was remarkably affected by the pH of the solution, the valances of metal ions, atomic weight and its initial concentrations. Equilibrium isotherms and interruptible diffusivities were investigated through batch experiments in analyzing the uptaking of aqueous solutions of metal ions onto PU foam, grafted PU, and granular activated carbon. The Frundlich constants k and 1/n have been determined for each metal ion to represent both the ability and the affinity of that ions towards the uptaking materials, respectively.     

高内相乳液法制备聚丙烯酰胺多孔水凝胶及应用

以亲水性二氧化硅纳米粒子（N20）和乳化剂Tween80为复合稳定剂,环己烷为油相制备高内相乳液,再以此乳液为模板制备聚丙酰胺（PAM）多孔水凝胶。乳液光学显微镜照片及PAM多孔水凝胶SEM照片表明N20用量及Tween80用量对材料孔径形貌及直径有直接影响;压汞仪数据表明当N20用量为3%、Tween80用量为9%时,多孔水凝胶平均孔径为38.06nm,孔隙率为77.54%,20h饱和吸水率可达402g/g;吸附实验表明PAM多孔水凝胶对Mn(Ⅱ)具有良好的吸附性能,吸附过程符合准二级动力学方程,属于化学吸附,当溶液pH为4时,120min可达吸附饱和,吸附量为474.64mg/g。     

Preparation and characterization of p-tert-butyl thiacalix[4]arene imbedded flexible polyurethane foam: An efficient novel cationic dye adsorbent

In this study, a new type of flexible polyurethane foam containing p-tert-butyl thiacalix[4]arene (TC4A) macrocycle was synthesized. TC4A macrocycle was incorporated into polyurethane foam as a part of crosslinking agent as well as glycerol. Structural, morphological, thermal and mechanical properties of this prepared foam were studied and compared with a polyurethane foam based on only glycerol as crosslinking agent, by Fourier transform infrared (FTIR), Scanning electron microscopy (SEM), Thermal gravimetric analysis (TGA), and dynamic mechanical thermal analysis (DMTA). The effect of introduction of TC4A crosslinker on cream time, rise time, apparent density, and water absorbency of the PU foams was evaluated. Moreover, it was shown that new TC4A-based polyurethane foam (TC-PUF) can be a high performance adsorbent for removal of malachite green from aqueous media using batch adsorption technique. The adsorption results indicated that TC-PUF has a high adsorption capacity of 58.82 mg/g for malachite green due to the presence of TC4A macrocycles in the structure of polyurethane foam. The kinetics of adsorption of malachite green was also investigated using the pseudo-first-order and pseudo-second-order kinetic models. The results of kinetic studies showed that the adsorption of malachite green onto TC-PUF followed pseudo-second-order kinetic model.     

Poly(acrylic acid)/poly(acrylamide) hydrogel adsorbent for removing methylene blue

Cationic dye can cause severe damage to the environment due to their refractory degradation, complex composition and strong stability. Hydrogels as adsorbents have been widely used to treatment the wastewater with dyestuff for their low prices, simple operations, and high efficiency. This work uses poly(acrylic acid) (PAA)/poly(acrylamide)(PAM)/calcium hydroxide nanoparticles (CHN) polymeric hydrogel absorbent to eliminate methylene blue (MB) dye. First, PAM/PAA/CHN hydrogel is produced through copolymerization of acrylic acid monomer and acrylamide monomer using inorganic CHN as cross-linker. And then, the adsorption performance of such PAM/PAA/CHN hydrogel adsorbent for adsorbing MB dye is explored at different conditions including pH, contacting time, adsorbent dosage, initial concentration of MB, and temperature. A maximum adsorption capability for adsorbing MB reaches 1,056 mg/g. Furthermore, the pseudo-first-order mode and Langmuir isotherm model can well describe adsorption behavior of MB dye onto such PAA/PAM/CHN hydrogel adsorbent. Thereby, as-prepared PAA/PAM/CHN hydrogel could be a potential adsorbent for eliminating organic dyes from wastewater.     

Fabrication of multifunctional TiO2–fly ash/polyurethane nanocomposite membrane via electrospinning

In this study, we demonstrate the fabrication of multifunctional composite polyurethane (PU) membrane from a sol gel system containing TiO₂ and fly ash (FA) nanoparticles (NPs). The adsorptive property of FA and photocatalytic property of TiO₂ can introduce different functionalities on PU mat for water purification. Different types of PU nanofiber mats were prepared by varying the composition of NPs in blend solution. FE-SEM, TEM, TGA, XRD, UV–visible spectra, and water contact angle measurement confirmed the incorporation of FA and TiO₂ NPs on/into PU nanofibrous mat. The influence of NPs on PU membrane was evaluated from the adsorption of heavy metals (Hg, Pb), removal of dyes (methylene blue), antibacterial activity, and water flux. The improvement of all these activities is attributed to the adsorptive property of FA and photocatalytic/hydrophilic property of TiO₂ NPs. Therefore, as-synthesized composite membrane can be utilized as an economically friendly filter media for water purification.     

Preparation and characterization of polyurethane foam/activated carbon composite adsorbents

A polyurethane foam (PU)/activated carbon (AC) composite was prepared by adding granular AC during the synthesis of PU foam, and subsequent carbonization. Nitrogen adsorption?Cdesorption isotherms and scanning electron microscopy were used to ascertain the pore structure and surface morphology of the samples. The prepared composite foams possess well-developed open cell structures. Under the conditions investigated, a higher carbonization temperature promoted development of porous structures. Thermogravimetric and derivative thermogravimetric analyses revealed the thermostability of the PU foam precursor/AC composites. The adsorption performance of the composites was evaluated using phenol, iodine and methylene blue (MB) as model compounds. A PU foam/AC composite with a maximum specific surface area of 655.0?m²/g, maximum iodine number of 525.2?mg/g, and maximum adsorption capacity of MB and phenol of 100 and 66.5?mg/g, respectively, was achieved.     

聚氨酯水凝胶在生物医学工程中的应用

介绍了聚氨酯(PU)水凝胶在药物缓释系统、创伤敷料、接触眼镜、组织工程材料和医用胶粘剂等领域中的研究进展,探讨了PU水凝胶在生物医学工程中的应用及发展趋势。