负载纳米TiO2织物的制备及甲醛降解

 为提高室内装饰织物对甲醛的吸附能力及过滤纺织材料对甲醛的过滤能力,采用射频磁控溅射方法,在纯棉机织物和涤纶针织物表面负载二氧化钛(TiO₂)功能纳米结构层。利用扫描电镜(SEM)和X射线衍射仪(XRD)分别分析其表面形貌和晶态结构,对2种负载TiO₂织物光催化降解甲醛气体的性能进行了对比分析。实验表明,在相同制备工艺条件下,TiO₂功能层的结构形态有较大区别,且负载纳米TiO₂的棉织物光催化降解甲醛气体的性能优于负载纳米TiO₂的涤纶织物。     

棉织物的纳米TiO2与TiO2抗紫外线整理

 针对棉织物抗紫外线性能较差的缺点,运用微乳液法制备了纳米TiO₂与纳米TiO₂材料,使所制备的纳米颗粒分散性好,纳米粉体颗粒细。通过纳米粉体紫外线透过率测试,得到纳米SiO₂与纳米TiO₂粉体的最佳配比。对棉织物进行退浆、煮练、漂白前处理,然后运用纳米SiO₂与纳米TiO₂复合粉体材料对棉织物进行抗紫外线整理。整理后棉织物的抗紫外线能力增强;强度、伸长率和断裂功均有所下降,但变化幅度不大;白度有所下降;折皱回复角增加;透气性也有一定程度的下降。     

纳米TiO2壳聚糖对柞蚕丝结构与性能的影响

 制备了粒径分布为30~60 nm的纳米TiO₂壳聚糖分散处理液,用该处理液对柞蚕丝进行改性,研究改性后柞蚕丝的结构与力学性能。结果表明:所制备的处理液中纳米TiO₂微粒分散良好;处理液中的柠檬酸和马来酸酐作为交联剂与柞蚕丝和壳聚糖之间发生交联反应,柞蚕丝经处理后结晶度提高并有β化趋势;处理后柞蚕丝纤维的纵向表面具有轻微的纵向条纹;其力学性能包括断裂强度、断裂伸长率、弹性模量和断裂功均有一定程度的提高。     

TiO2/SiO2的制备与光催化降解甲基橙

 为了探讨TiO₂晶粒形貌对光催化过程的作用规律,研究吸附法和浸渍法制备的TiO₂光催化剂降解甲基橙的过程,并考察制备反应条件对催化剂形貌和活性的影响。通过剖析反应的基本过程后得出,扩散过程与表面反应过程耦合,催化剂活性与甲基橙浓度的相对高低决定反应过程的控制步骤,从而对表观级数产生影响。在催化剂活性的考评中发现,低Ti含量以及小粒径情况下影响光催化的关键因素是晶型,其次为含量、粒径。吸附法制备的光催化剂Ti含量高,粒径小,可控性好,具有比浸渍法制备的材料更好的催化性能。随着水量的增加,吸附相反应技术的优势越来越显著。     

纳米SiO2的分散对淀粉浆膜力学性能的影响

 为了探讨纳米SiO₂的分散状况对纳米SiO₂/淀粉复合浆料浆膜力学性能的影响,采用超声波对纳米SiO₂进行分散,提取经不同时间分散的纳米SiO₂水基悬浮液,用AFM、TEM观察纳米SiO₂的分散状况和其团聚体粒径,并结合不同分散时间下的浆膜力学性能测试数据,研究纳米SiO₂不同分散状况下复合浆料浆膜力学性能的变化。结果表明,当超声波分散达到50 min时,纳米SiO₂的分散状况较好,并保持稳定,用此分散液制备的浆膜力学性能最佳。     

TiO2/ACF复合滤料光降解甲醛的实验研究

 以钛酸丁酯[Ti(OBu)4]为原料,用溶胶凝胶法制备纳米TiO₂溶胶,采用浸渍法将溶胶整理到活性炭纤维(ACF)滤料上,并对ACF滤料原样、整理样光催化氧化甲醛气体的性能进行静态、动态对比实验。静态实验中,弱光源条件下ACF滤料原样、整理样的甲醛净化率分别为33.3%、39.6%,在强光源条件下分别为38.6%,49.2%;动态实验中,弱光源条件下ACF滤料原样、整理样的甲醛净化率分别为69.9%、77.1%,在强光源条件下分别为77.1%,85.5%。证明纳米TiO₂在强光源和弱光源条件下均可以光降解甲醛。     

TiO2/羊毛粉体复合改性聚氨酯膜及其性能

用超细羊毛粉体改性聚氨酯能得到透湿性较好的膜,但其力学性能下降较大,为了改善聚氨酯膜的防水透湿性和保持膜的力学性能,用超细羊毛粉体和TiO₂复合改性聚氨酯的方法制成了聚氨酯干法膜。探讨了粉体的加入对干法膜力学、透湿、吸湿、防水等性能的影响。结果表明,羊毛超细粉体与微米TiO₂共混是一种改善聚氨酯膜透湿性能的有效途径。     

TiO2/羊毛粉体复合改性聚氨酯膜及其性能

 用超细羊毛粉体改性聚氨酯能得到透湿性较好的膜,但其力学性能下降较大,为了改善聚氨酯膜的防水透湿性和保持膜的力学性能,用超细羊毛粉体和TiO₂复合改性聚氨酯的方法制成了聚氨酯干法膜。探讨了粉体的加入对干法膜力学、透湿、吸湿、防水等性能的影响。结果表明,羊毛超细粉体与微米TiO₂共混是一种改善聚氨酯膜透湿性能的有效途径。     

合成聚合物改性TiO2及对加填纸主要性能的影响

采用3种合成聚合物(PDADMAC、PVAm和PNVF)分别对TiO₂进行改性,并用球磨机进行机械研磨,将改性后的TiO₂作为填料用于装饰原纸的抄造中,探究了不同改性剂用量下获得的改性TiO₂对加填后装饰原纸主要性能的影响。结果表明：改性剂PDADMAC用量为2.5%进行TiO₂改性时,与未改性TiO₂加填纸相比,改性TiO₂加填纸的抗张指数和填料留着率分别提高了21.0%和9.5%;PVAm用量为2.0%时,改性TiO₂加填纸的抗张指数和填料留着率比未改性TiO₂加填纸分别提高了24.7%和5.5%;PNVF用量为1.5%时,改性TiO₂加填纸强度性能和填料留着情况较优。     

纳米TiO2胶体絮凝-光催化氧化-砂滤深度处理造纸废水研究

研究了纳米TiO₂胶体絮凝-光催化氧化-砂滤深度处理造纸废水的效果。分析了絮凝剂的选择和用量、光催化剂用量、光催化时间和外加氧化剂等对废水COD_Cr去除效果的影响;研究证实了样品中残留微量纳米TiO₂胶体对COD_Cr测定的影响,并利用砂滤除去。实验结果表明,以用量为0.01%(相对于废水质量,下同)的纳米TiO₂胶体为絮凝剂对经序列间歇式活性污泥法（SBR）处理后的造纸废水进行处理,在光催化剂用量（质量分数）0.05%,曝气并紫外光照射2 h时,沉降后的上层液体经过砂滤,废水COD_Cr从210 mg/L降到43.0 mg/L。     

RSM optimized self-cleaning nano-finishing on polyester/wool fabric pretreated with oxygen plasma

In this study, polyester/wool blended fabric was coated with titanium dioxide nanoparticles. To enhance the adsorption and loading of nanoparticles on wool and polyester fibers, the samples were pretreated by low-temperature oxygen plasma. Citric acid was used to fix the TiO₂ nanoparticles on the fibers. The self-cleaning property of the finished samples was tested under UV-A light. The effect of plasma treatment time besides the concentrations of TiO₂ nanoparticles and citric acid on the self-cleaning properties of the samples was analyzed and optimized using response surface methodology. The surface chemistry and morphology of the samples were studied using Attenuated total reflectance-fourier transform infrared spectorscopy (ATR-FTIR) and field emission scanning electron microscope, respectively. The results showed that plasma treatment has a great effect on the loading of the nanoparticles on the surface of the fibers and enhancing the self-cleaning properties of the finished samples. The plasma-treated samples showed better water absorbency, enhanced tensile strength and approximately the same handle compared to raw samples after coating with TiO₂ nanoparticles.     

氟代聚丙烯酸酯乳液的制备及应用

 以(NH4)2S2O8为引发剂,将丙烯酸十二氟庚酯(RfAA)、丙烯酸丁酯(BA)和丙烯酸羟丙酯(HPAA)进行乳液聚合,制备了阴离子氟代聚丙烯酸酯(PAFBA)乳液。用FT-IR对PAFBA膜的结构进行表征,通过扫描电镜(SEM)对PAFBA整理后棉纤维表面的微观形貌进行观察,并对其应用性能进行研究。结果表明:PAFBA可在纤维表面成膜,该膜能使整理后棉织物与水的接触角达到128.0°,静态吸水时间超过6 h;向PAFBA整理液中加入适量醋酸锌,可明显提高整理后棉织物的疏水性能;恒定醋酸锌用量时,PAFBA乳液用量对整理后棉织物的疏水效果亦有影响,其最佳用量为2 g。     

Modified Rice Straw as a Template in Syntheses of Nano TiO2 Loaded on Wool Fibers for Wastewater Treatment

Industrialization of textile produces large amounts of colored wastewater and recycling of that wastewater is recently under the scope. The current work is implemented to use rice straw as a template for preparation of nano TiO₂ to be applied in decolorization of wastewater of textile industries. Different treatments including silica removal and esterification were performed for rice straw to produce highly reactive nanotitanium dioxide. Size, morphological shape, and surface area of the so obtained TiO₂ nanoparticles were observed to be influenced by rice straw treatments. Percentage of anatase phase in titanium dioxide was increased from 41.6% to 75.0% after removing of silica and modification with citric acid of rice straw. The particle size of anatase was significantly reduced from 88.6 nm to 10.5 nm while the BET surface area of nanotitanium dioxide was enlarged from 41.2 m²/g to 84.7 m²/g. The prepared TiO₂ nanoparticles were loaded onto wool fibers and the photocatalytic properties of nano TiO₂ powder before and after loaded to fiber were measured against methylene blue dye. The dye removal percentage raised from 92.5 to 99.2 by using of nano TiO₂ powder-loaded wool fibers compared to nano TiO₂ powder.     

Hydrothermal Treatment of Wool Fibers with Tetrabutyl Titanate and Chitosan

In order to improve the dye depth of TiO₂-modified wool fibers, chitosan is incorporated with tetrabutyl titanate in preparing the nanosized TiO₂ particles, which are loaded on the surfaces of wool fibers, during hydrothermal process. The TiO₂ coated wool fibers are subsequently dyed with Lansol Blue 3G. The structural changes of wool fibers before and after treatments are characterized by several techniques, such as field emission scanning electron microscope, energy-dispersive X-ray, transmission electron microscope, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, thermal gravimetric analysis, and diffuse reflectance spectrum. The properties of tensile, antibacterial activity, yellowness and whiteness indices, dye uptake, K/S value, color fastness to washing, rubbing, and artificial light are also compared. It is found that the as-prepared TiO₂ particles with pure anatase phase are easy to agglomerate because of the introduction of chitosan. Meanwhile, the aggregated particles are deposited on the surface of wool fibers via a simple hydrothermal route. Compared with the original wool fibers, the thermal behaviors of the TiO₂ coated wool fibers change slightly. The performances of UV protection, antibacterial activity, dyeing depth, and color fastness to wet rubbing and artificial light are improved to some degree. However, the tensile properties of wool fibers decrease but not too much.     

Dietary vitamin E supplementation, an ascorbic acid preparation, and packaging effects on colour stability and lipid oxidation in mince made from previously frozen lean beef

The effect of extra vitamin E (2025 International Units animal^-1 day^-1) in the diet of bulls on the colour stability and lipid oxidation of lean mince was studied. Control and enriched diets were provided for the last 136 days before slaughter. Minces were prepared from M. biceps femoris and M. semitendinosus that had been stored for 2 months at -40 °C. Samples of minces with and without an ascorbic acid preparation (AAP) from control (CON) and supplemented (SUP) beef were packaged, half on trays over-wrapped with an oxygen-permeable foil and half in modified atmosphere (MA) packs (gas mixture applied: O₂/CO₂/N₂, 75/20/5). Meats were displayed for 7days at 7 °C in an illuminated environment. The SUP meat was more resistant to lipid oxidation than the CON meat was. Also, the AAP consistently delayed lipid oxidation. A strong synergistic effect of both vitamins in this regard was demonstrated for the MA condition. MA packaging overall led to increased lipid oxidation. Colour measurements of SUP versus CON meats, without the AAP, generally failed to detect differences in redness values. The positive effect on the colour of freshly minced lean meats obtained by supplementation with vitamin E appeared to be almost nullified in minces made from previously stored frozen muscles. A sensory panel, however, still tended to judge the attractiveness of the colour of the SUP meat greater than that of CON meat. Addition of the AAP improved colour stability. Compared to the foil-overwrapped meat, colour was better retained in the MA packaged meat.     

Antimicrobial finishing of cotton fabrics based on gamma irradiated carboxymethyl cellulose/poly(vinyl alcohol)/TiO2 nanocomposites

Synthesis of nanoparticles with antibacterial properties is of great interest for the development of textiles finishing, in general, and cotton fabric, in particular. In this work, TiO₂ nanoparticles at different concentrations were synthesized using nitric acid as a reducing and stabilizing agent. Cotton fabrics were first impregnated, to a pick-up of 100%, in colloidal solutions containing carboxymethyl cellulose (CMC)/polyvinyl alcohol(PVA)/TiO₂ nanocomposites. After that, the coated fabrics were exposed to gamma irradiation to produce TiO₂ nanoparticles stabilized in cross-linked CMC/PVA hydrogel. The formation of TiO₂ nanoparticles was confirmed by ultra violet/visible (UV/vis) and transmission electron microscopy, and the particle size distribution of the nanoparticles was determined using the dynamic light scattering. The surface morphology of the finished fabrics was examined by scanning electron microscopy (SEM). The SEM micrographs revealed that TiO₂ nanoparticles were deposited on the surface of cotton fibers. The antibacterial activity of the treated fabrics loaded with TiO₂ nanoparticles was evaluated against Escherichia coli (Gram -ve) bacteria.     

二安替比林甲烷分光光度法测定功能纤维中TiO2含量

 针对功能纤维中添加TiO₂的含量测定问题,对功能纤维样品采用高温消化、混酸溶解的前处理方式,以抗坏血酸作Fe³⁺、Cu²⁺的掩蔽剂,二安替比林甲烷作为显色剂,用分光光度法在λ=390 nm波长处测定功能纤维中纳米TiO₂的含量。钛的质量浓度在0.005~0.65 mg/L范围内标准液质量浓度与吸光度呈良好的线性关系,线性方程为y=1.407 1x-0.009 3(R2=0.999),检测限为0.005 mg/L,平均回收率98%以上,RSD=0.59%。该方法简便快速,准确度高,实用性强。     

Characterization and antibacterial property of Kapok fibers treated with chitosan/AgCl–TiO2 colloid

The aim of this research is to investigate the antibacterial activity of Kapok fibers modified with AgCl/TiO₂ and Chitosan colloid. A very simple, single-step (pad-dry-cure) method was used for the application of AgCl/TiO₂ and Chitosan colloid on kapok fibers, the chemicals used are easily available. Different blend ratios of chitosan and AgCl/TiO₂ colloid were applied to the bleached kapok fibers and antibacterial properties were assayed against gram positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. The treated kapok fibers were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). It was observed that the bacterial growth was significantly reduced in the samples which had a higher concentration of chitosan and AgCl/TiO₂ colloid. However, a significant reduction in bacterial growth with the use of this colloid was observed.     

Effect of Oxidation on the Emulsifying Properties of Myofibrillar Proteins

The aim of this work was to investigate the effect of chemical oxidation on the emulsifying properties of myofibrillar proteins. Myofibrillar proteins were oxidized by a hydroxyl radical generating system (Fenton reaction). Structural changes of oxidized or non-oxidized myofibrillar proteins were determined using surface hydrophobicity (H₀) and Fourier transform infrared (FTIR) spectroscopy. The results suggested that H₀ increased (p?<?0.05) after treatment with oxidizing agent. Result from FTIR suggested that protein aggregation occurred and there was an increase in β-sheet structure accompanied by a decrease in turns, alpha helix, and random structures with the increase of oxidizing agent. Changes in zeta potential of the test emulsions suggested that protein oxidation could alter the electric charge of myofibrillar proteins. The analysis of the emulsions showed that protein oxidation had a negative effect on the emulsifying properties of myofibrillar proteins due to changes in electric charge, surface active properties, and protein molecular flexibility.