Objective measurement of fabric properties of the plasma‐treated cotton fabrics subjected to cocatalyzed wrinkle‐resistant finishing

The wrinkle resistance treatment together with plasma pretreatment is especially very important to cotton fabrics because of their high wrinkling tendency. However, the processes improved the wrinkle recovery property of cotton fabrics, but, at the same time, may worsen the fabric handle, which is an important factor when designing the end‐uses of fabric because handling of fabric also a critical factor for purchasing decision. The Kawabata Evaluation System for Fabrics (KES‐F) measures the scale of “basic hand” and “total hand” values determined by the combined results of sensory tests conducted by the instrumental measurements. In the present article, the effects of plasma treatment and catalyzed 1,2,3,4‐butanetetracarboxylic acid (BTCA) treatment on the fabric yellowing are also studied. The results found that the wrinkle‐resistant treatment had a negative effect on the tensile properties, shearing properties, bending properties, and surface friction and variation, whereas the compressional properties are improved by the treatment. In addition, the plasma treatment improves the tensile properties and bending properties but not the compressional properties, shearing properties, and surface friction and variation. Besides, it is concluded that these treatments can influence not only the fabric handle but also the yellowness of fabrics. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

A comparative study of the bactericidal effect of photocatalytic oxidation by TiO2 on antibiotic‐resistant and antibiotic‐sensitive bacteria

BACKGROUND: In recent decades, the increase in antibiotic‐resistant bacteria has become one of the most significant problems in public health. Titanium dioxide (TiO₂) has the potential to inactivate antibiotic‐resistant bacteria. RESULTS: In this study, TiO₂ that had been activated by ultraviolet A (UV‐A) irradiation was used to inactivate the following three antibiotic‐resistant bacteria in suspension: methicillin‐resistant Staphylococcus aureus (MRSA), multidrug‐resistant Acinetobacter baumannii (MDRAB) and vancomycin‐resistant Enterococcus faecalis (VRE). For comparison, the following antibiotic‐sensitive strains were used as controls: S. aureus (MSSA), A. baumannii (MDSAB), E. faecalis (VSE), Escherichia coli and the bacteriophage MS2. Results demonstrated that MSSA and MRSA were equally susceptible to TiO₂ photocatalysis, and the susceptibility of MDRAB was double that of MDSAB (P < 0.05). The susceptibility of VSE was 2.4 times that of VRE (P < 0.05). The results obtained from multiple regression analysis indicated that TiO₂ reaction time had the greatest influence on microbial survival following TiO₂ exposure in the presence of UV‐A. CONCLUSION: The development of antibiotic resistance does not appear to be correlated to increased resistance to TiO₂ photocatalysis, but TiO₂ in the presence of UV‐A still effectively reduces the number of antibiotic‐resistant microbes in suspension by 1–3 logs. Copyright © 2010 Society of Chemical Industry     

预处理对微胶囊改性聚酯织物舒适凉爽性的影响

由于聚酯纤维的化学性质稳定、纤维表面光滑,不易与后整理剂相结合,因此利用薄荷油微胶囊后整理对聚酯织物进行舒适凉爽改性时,存在附着量少、改性效果差的缺点。为解决这一问题,本文在后整理前增加了碱预处理和等离子体预处理。通过对聚酯织物原样、无预处理后整织物、碱预处理后整织物和等离子体预处理后整织物进行舒适凉爽性能测试,深入分析两种预处理方法对聚酯织物改性效果的影响。结果表明：等离子体预处理在织物透湿、导水、润湿、速干和凉爽性改性方面促进作用更明显,相比无预处理后整织物,等离子体后整织物的透湿率、经向和纬向芯吸高度、滴水扩散时间、蒸发速率及接触凉感系数分别提高了3.32%、40.24%、27.25%、80.39%、21.21%和5.59%;碱预处理则在织物透气性和吸水性改善方面的效果更佳,相比无预处理的后整织物,可将织物的透气率和吸水率分别提高43.43%和13.03%。因此,两种预处理方法对聚酯织物舒适凉爽性的改性效果有显著促进作用。     

二氧化钛表面包覆氧化铝的形态和机理分析

采用分光光度法研究了三氧化二铝的pH-吸光度（A）曲线,确定了铝的沉积pH范围为4.0～10.5;研究了沉积pH和沉积时间对产品颜料性能的影响。采用XRD分析了三氧化二铝在不同pH条件下沉积的晶型,在酸性条件下沉积为无定型,碱性条件下沉积为勃姆石型;还研究了不同pH下沉积的三氧化二铝的比表面积,结果表明在碱性和酸性条件下,三氧化二铝比表面积分别为69.71 m²/g和37.80 m²/g。采用电子能谱对二氧化钛样品表面结构进行表征,2p电子轨道结合能的变化表明铝以Al-O-Ti键的形式结合在二氧化钛表面。     

烧结温度对TiO2/不锈钢中空纤维复合膜结构和性能的影响

不锈钢中空纤维膜基膜孔径大,直接涂覆分离层容易产生表面缺陷。在二氧化钛悬浮液中加入聚乙烯醇作为黏结剂,通过真空辅助抽滤法在不锈钢中空纤维基膜表面形成一层均匀的分离层。通过高温烧结得到了TiO₂/不锈钢中空纤维复合膜,考察了烧结温度对于TiO₂/不锈钢中空纤维复合膜表面分离层形貌和结构的影响。不同烧结温度时,TiO₂/不锈钢中空纤维复合膜的表面形貌有所差异;随着烧结温度的升高,不锈钢复合膜的孔径和纯水通量均先升高再下降。当烧结温度为500℃时,表面涂层均匀,孔径分布集中,水通量较高。最后,以SPT-500膜测试了水包油乳液分离效果,分离效率达到99%以上,且具有良好的抗污染性能。     

一锅法合成Janus纳米片及其对PS/TiO2复合材料的增容作用研究

利用一锅法合成了Janus纳米片（JNSs）,通过扫描电子显微镜（SEM）、电致冷X射线能谱仪（EDS）、动态混合流变仪、动态力学热分析仪（DMA）和万能材料试验机等对JNSs的表面形貌和化学成分进行了表征,考察了JNSs对聚苯乙烯/二氧化钛（PS/TiO₂）共混体系流变性能的影响,以及JNSs对PS/TiO₂复合材料动态力学性能、力学性能、表观形貌的影响,并对JNSs对复合材料的界面增容作用机理进行了探讨分析。结果表明,JNSs两面的粗糙程度不同,粗糙凹面含有氨基,光滑凸面含有双键;JNSs用作PS/TiO₂共混体系的相容剂时,能够增强界面作用力,改善无机粒子和有机聚合物的相容性;含0.5 份（质量份,下同）JNSs的PS/TiO₂复合材料的玻璃化转变温度（T_g）从PS的100 ℃提高到了107 ℃;同时,JNSs在外力作用下沿力的方向取向需要耗散能量,使得其拉伸强度较PS/TiO₂提高了13.43 %,断裂伸长率由12 %增加到了18 %。     

Effect of Polyethylene Glycol Modification of TiO2 Nanoparticles on Cytotoxicity and Gene Expressions in Human Cell Lines

Nanoparticles (NPs) are tiny materials used in a wide range of industrial and medical applications. Titanium dioxide (TiO(2)) is a type of nanoparticle that is widely used in paints, pigments, and cosmetics; however, little is known about the impact of TiO(2) on human health and the environment. Therefore, considerable research has focused on characterizing the potential toxicity of nanoparticles such as TiO(2) and on understanding the mechanism of TiO(2) NP-induced nanotoxicity through the evaluation of biomarkers. Uncoated TiO(2) NPs tend to aggregate in aqueous media, and these aggregates decrease cell viability and induce expression of stress-related genes, such as those encoding interleukin-6 (IL-6) and heat shock protein 70B' (HSP70B'), indicating that TiO(2) NPs induce inflammatory and heat shock responses. In order to reduce their toxicity, we conjugated TiO(2) NPs with polyethylene glycol (PEG) to eliminate aggregation. Our findings indicate that modifying TiO(2) NPs with PEG reduces their cytotoxicity and reduces the induction of stress-related genes. Our results also suggest that TiO(2) NP-induced effects on cytotoxicity and gene expression vary depending upon the cell type and surface modification.     

离子强度和富里酸对纳米 TiO2在土壤中迁移的影响

采用自然土壤作为介质,研究了离子强度、富里酸对纳米TiO2在土壤中迁移性能的影响。结果表明,随着离子强度从0 mM增加至0．5 mM和5 mM,纳米TiO2在土壤中的相对流出浓度（ C／C0）从0．85分别降低为0．45和0。然而,体系中含有富里酸时,纳米TiO2在土壤中的迁移能力变强了,5 mg／L和10 mg／L的富里酸分别使nTiO2的相对流出浓度提高到0．89和0．95,大大增加其环境风险。     

Effect of Heat-Treatment on the Mechanism and Kinetics of the Hydrogen Evolution Reaction on Ni—P + TiO2 + Ti Electrodes

Composite Ni—P + TiO₂ + Ti layers were prepared by codeposition of Ni—P alloy with TiO₂ and Ti powders from a solution containing suspension of TiO₂ and Ti particles. The electrodeposition was carried out under galvanostatic conditions at room temperature. The layers exhibited an amorphous Ni—P matrix in which crystalline TiO₂ and Ti were embedded. On the deposit surface, the nonstoichiometric Ti oxide, Ti₁₀O₁₉, and intermetallic compounds, NiTi, formed during the electrodeposition, were also present. The heat treatment of these layers in argon leads to the crystallization of Ni—P matrix and formation of nonstoichiometric Ti oxides, detected by XRD. Electrolytic activity towards the hydrogen evolution reaction (HER) was studied on these electrode materials before and after heat treatment. The mechanism of the HER was also studied, and the kinetic parameters were determined using steady-state polarization and electrochemical impedance spectroscopy (EIS). An increase in activity occurring after heating of Ni—P + TiO₂ + Ti layers is related to TiO₂ reduction and formation of nonstoichiometric Ti oxides: Ti₁₀O₁₉(400 °C), Ti₇O₁₃(500 °C) and Ti₄O₇(800 °C). It is postulated that the increase in electrochemical activity is related to the properties of these oxides and a facility for H reduction/adsorption on their surface, as well as to the presence of NiTi intermetallics as compared with the Ni—P + TiO₂ + Ti electrode.     

Correlation between limiting oxygen index and phosphorus/nitrogen content of cotton fabrics treated with a hydroxy‐functional organophosphorus flame‐retarding agent and dimethyloldihydroxyethyleneurea

The combination of a hydroxyl‐functional organophosphorus flame‐retarding agent (FR) and dimethyloldihydroxyethyleneurea (DMDHEU) was used as a durable flame‐retardant finish system for cotton fabrics. DMDHEU functions as a binder between FR and cotton cellulose, thus making this flame‐retarding system durable to home laundering. DMDHEU also provides nitrogen to this system, therefore enhances its performance. Limiting oxygen index (LOI) is one of the most commonly used parameters to indicate the flammability of textiles and other polymeric materials. In this research, we investigated the correlation between LOI and phosphorus/nitrogen content on the cotton fabric treated with that durable flame‐retardant system. Phosphorus concentration on the fabric was analyzed by inductively coupled plasma atomic emission spectroscopy, whereas the nitrogen content was determined indirectly by measuring the carbonyl band intensity in the infrared spectra of the treated fabric. We developed a statistical model to predict LOI of the cotton fabric treated with FR and DMDHEU based on the phosphorus concentration and the intensity of carbonyl band of DMDHEU on cotton. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1885–1890, 2003     

钙镁离子对二氧化钛光催化氧化水中腐殖酸的影响

考察了间歇反应器中钙离子存在下腐殖酸分子在TiO2颗粒表面的吸附行为,进而以125 W (Emax=365 nm) 汞灯为中心光源,考察了钙镁离子对二氧化钛光催化氧化水中腐殖酸的影响. 结果表明,在腐殖酸初始浓度C0=20 mg/L, [Ca2+]=80 mg/L, pH=7和TiO2=1 mg/ml实验条件下,经2.5 h的光催化反应,腐殖酸的脱色率为100%,氧化分解率接近100%,矿化率大于95%.     

Effect of calcination temperature on the catalytic activity of Au colloids mechanically mixed with TiO2 powder for CO oxidation

In order to elucidate the role of the contact structure between gold and metal oxide support in low-temperature CO oxidation, a mechanical mixture of colloidal gold with TiO₂ powder was prepared and calcined at different temperatures. The sample calcined at 473 K, which is composed of spherical gold particles with a mean diameter of 5.1 nm and TiO₂ powder, is poorly active for CO oxidation at temperatures up to 473 K. The catalytic activity appreciably increases with an increase in calcination temperature up to 873 K even though gold particles grow to larger ones, reaching a level with almost the same turnover frequency as that of Au/TiO₂ prepared by a deposition–precipitation method. This revised version was published online in July 2006 with corrections to the Cover Date.     

Effect of titanium dioxide (TiO2) distribution and minute amounts of carbon black on the opacity of PVDF based white composite films

There is a contradiction in making completely opaque and white plastic film with a required high TiO₂ filling fraction, which resulted in inefficient pigment utilization and high cost. Two methods were used here to overcome the contradiction. Firstly, TiO₂ was grafted with poly(methyl methacrylate) (PMMA) by atom transfer radical polymerization to improve the pigment dispersion in poly(vinylidene) fluoride (PVDF). Secondly, minute amounts of carbon black (CB) were added into the PMMA‐g‐TiO₂/PVDF system to enhance opacity and decrease TiO₂ fraction. The structure, morphology, and properties of PMMA‐g‐TiO₂ hybrid particles and composite films were investigated by FTIR, TEM, TGA, SEM, DMA, covering power meter, and UV/VIS spectrophotometer, etc. It was observed that PMMA‐g‐TiO₂ was dispersed uniformly as individual particles in PVDF due to the good compatibility between PMMA and PVDF. Therefore, the opacity of PMMA‐g‐TiO₂/PVDF films was markedly higher than unmodified‐TiO₂/PVDF ones. Adding minute amounts of CB can significantly increase the opacity of the thin film due to its absorption effect on decreasing light transmittance. The contrast ratio (CR) of the PMMA‐g‐TiO₂/PVDF film with 20 μm thickness and 25 vol % TiO₂ was 97.67%, lower than the critical CR 98% for a complete opacity, however, the CR of sample with 10 vol % TiO₂ was 98.1% as the CB concentration was 2 × 10^?4 g/cm³, saved more than 15% TiO₂. We proposed that a critical thickness d₀ existed for the CB/PMMA‐g‐TiO₂/PVDF composite films, under which the light reflectance increased as a function of thickness, otherwise, the reflectance kept constant. Besides, d₀ could be decreased by increasing CB concentration. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43064.     

Effect of TiO2 and 11 minor elements on the reactivity of ground-granulated blast-furnace slag in blended cements

Ground-granulated blast-furnace slags (GGBS) are glasses (>99%) of the CaO-Al₂O₃-SiO₂ compositional system and are widely used as supplementary cementitious materials. Differences in reactivity of GGBS were screened by modifying the content of 12 minor elements (namely Ba, Ce, Cs, Cr, K, Mn, P, Sn, Sr, Ti, V, and Zr). Scanning electron microscopy observations showed that most elements entered the silicate glass matrix, only Sn was reduced to its metallic form and P accumulated in minor minerals. Mortar strength tests showed that 2 day compressive strength was reduced by >50% for a TiO₂ content of 2.5 wt% in the slag. At 28 days the loss in compressive strength was still >40%. Calorimetric tests on other element additions showed that the content of network modifiers (Ba, Cs, K and Sr) and GGBS reactivity are positively correlated, whereas Ce, Cr, V, and Zr significantly decreased reactivity. Finally, it is shown that these effects can be estimated by the concentration and the weighted field strength of the added element.     

介孔TiO2晶须材料的硅烷化改性及其对载体pzc值和酶负载性能的影响

以3-氨丙基三乙氧基硅烷(APTES)对介孔二氧化钛晶须(MTiO₂_ws)进行表面修饰,使其电荷零点值(pzc)由5.3提高至6.8,改性后材料MTiO₂_ws-APTES的比表面积略有上升,但孔结构基本不变。以MTiO₂_ws-APTES为载体对γ-谷氨酰转肽酶(GGT)进行了固定化,当给酶量小于150 U·g^-1时,酶活回收率均大于99%,固定化酶MTiO₂_ws-APTES-GGT的比活力最高可达184.0 U·g^-1,对酶的负载性能显著优于MTiO₂_ws。相比于游离酶,MTiO₂_ws-APTES-GGT的最适温度和热稳定性均略有下降,但pH稳定性明显优于游离酶和以MTiO₂_ws为载体的固定化酶(MTiO₂_ws-GGT); MTiO₂_ws-APTES-GGT对γ-谷氨酰对硝基苯胺(GpNA)的亲和力常数(K_m)为0.889 mmol·L^-1,较游离酶有所上升,但小于MTiO₂_ws-GGT。MTiO₂_ws-APTES-GGT的稳定性良好,经4℃下储藏60 d,连续使用21批次后残余酶活仍可达初始值的80.07%。     

Effect of plasma pretreatment on the wrinkle‐resistance properties of cotton fibers treated with a 1,2,3,4‐butanetetracarboxylic acid–sodium hypophosulfite system with titanium dioxide as a cocatalyst

A 1,2,3,4‐butanetetracarboxylic acid (BTCA)–sodium hypophosulfite (SHP) wrinkle‐resistance system played an important role in improving the wrinkle‐resistance properties of cotton fibers. In this study, titanium dioxide (TiO₂) was used as a cocatalyst to further enhance the wrinkle‐resistance properties of BTCA–SHP‐treated cotton fabrics, that is, those treated with (1) 5% BTCA and 10% SHP; (2) 5% BTCA, 10% SHP, and 0.1% TiO₂; and (3) 5% BTCA, 10% SHP, and 0.2% TiO₂. In addition, the effect of plasma as a pretreatment process on the wrinkle‐resistance properties of the three treatment systems was also studied. The experimental results reveal that the wrinkle‐resistance properties of cotton fibers were improved after different wrinkle‐resistance treatments. In addition, the plasma pretreatment further enhanced the wrinkle‐resistance treatments to different extents, depending on the process parameters. Scanning electron microscopy images confirmed that such plasma pretreatment conditions imparted the best crosslinking effect on the cotton fibers. However, the wrinkle‐resistance‐treated cotton specimens had lower tensile strength and tearing strength values compared to the control sample, whereas the plasma pretreatment and cocatalyst may have compensated for the reduction in the mechanical strength caused by the wrinkle‐resistance agents. In this article, the optimum conditions for the plasma pretreatment on the basis of the result of the wrinkle‐recovery angle were analyzed with an L₉(3)³ orthogonal array testing strategy technique. The results showed that plasma treatment conditions with (1) a 10 mm/s speed, (2) a 0.1 L/min oxygen flow rate, and (3) a 4‐mm jet‐to‐substrate distance together caused a significant improvement in the wrinkle‐resistance properties of the cotton fibers treated with the three different BTCA treatments. Moreover, the treatment speed was the dominant factor, followed by jet‐to‐substrate distance and oxygen flow rate, in affecting the extent of improvement. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Surface modification of TiO2 particles with 12-hydroxy stearic acid and the effect of particle size on the mechanical and thermal properties of thermoplastic polyurethane urea elastomers

The efficient surface modification of titanium dioxide (TiO₂) particles with different sizes was first carried out with “water only method” (Appl. Surf. Sci. 2018, 447, 664–672) developed in our group using 12-hydroxy stearic acid (12-HSA) as the modifier. The 12-HSA-modified TiO₂ particles with different sizes were then used to explore their effect on the mechanical and thermal properties of a thermoplastic polyurethane urea (TPUU) elastomer with superior mechanical and thermal properties produced newly in our lab using nonsymmetric alicyclic diisocyanate and diamine. Orthogonal experimental results showed that the order of impact of each factor on the modification efficiency of TiO₂ particles was: Temperature > time > modifier content. It was found that, in the nanometer (≤100 nm) range, smaller particles were more helpful to enhance the tensile strength of the TPUU elastomer, while larger ones to increase more significantly the elongation at break. Besides, the TiO₂/polyurethane urea nanocomposites exhibited much better thermomechanical performance than the pristine TPUU elastomer, and the thermomechanical performance of the nanocomposites increased with decreasing particle size.     

Effect of LaB6 additions on densification,microstructure, and creep with oxide scale formation in ZrB2-SiC composites sintered by spark plasma sintering

A comparative study has been carried out on densification, microstructure, and creep with oxide-scale formation in ZrB₂-20 vol.% SiC-(7, 10 or 14 vol.%) LaB₆ composite containing B₄C and C as additives, and prepared by spark plasma sintering at 1800 °C under 70 MPa ram pressure. Addition of LaB₆ has promoted densification of composites by scavenging oxygen impurity, thereby increasing their hardness. Constant load compressive creep tests at 1300 °C under 47 and 78 MPa stresses have shown the lowest creep rate in the 10 vol.% LaB₆ composite. The stress exponents obtained for composites having 10 vol.% LaB₆ (～1.3 ± 0.1) and 14 vol.% LaB₆ (～2.6 ± 0.2) suggest respectively, grain boundary diffusion with intergranular glassy phase formation and dislocation glide as operating mechanisms. Intergranular cracking caused by grain boundary sliding appears as the damage mechanism. Oxide scales formed during creep exhibit greater thickness and defect concentration than those by isothermal exposure at 1300 °C within similar duration.