Biosurfactants from Urban Wastes for Detergent Formulation: Surface Activity and Washing Performance

To promote biobased products for industry, six biosurfactants (BS) isolated from green and food urban residues aged under aerobic digestion for 0–60 days were investigated for their chemical composition, surface activity properties and detergent performance in fabric washing in comparison with commercial anionic and nonionic surfactants (CS). The BS exhibited a range of chemical composition and surface activity properties presumably related to their different biomass sources. Surface tension data for these substances correlated meaningfully with performance data in fabric washing. It was found that BS have similar performances as CS when used neat, but the 1:1 w/w BS–CS mixes are characterized by significant synergy. High sensitivity to water hardness and fabric yellowing were found to be the main deficiencies for the BS. However, both effects are minimized or are not critically evident when the BS are used together with CS and/or in common detergents formulations. The results indicate that when used above critical micellar concentration, no significant or critical performance differences are evident within the whole group of BS or between BS and CS. These facts encourage expectations for industrial production and real commercialization of BS as components of detergents formulations.     

pH/redox/thermo-stimulative nanogels with enhanced thermosensitivity via incorporation of cationic and anionic components for anticancer drug delivery

To explore the potential biomedical applications of nanogels, it is a key factor to improve their thermosensitivity. In this paper, triple-responsive nanogels poly(N-isopropylacrylamide–N,N′-dimethylaminoethyl methacrylate–acrylic acid) (PNDA) were synthesized via in situ incorporating both cationic components and anionic components into a normal thermosensitive polymer matrix. The triple-monomer constructed PNDA nanogels displayed an enhanced thermosensitivity as compared with dual-monomer constructed PND nanogels. The PNDA nanogels presented higher encapsulation efficiency (～89%) and exhibited better pH/redox/thermo-responsivenesses in an anticancer drug delivery. In vitro biological study indicated that the PNDA nanogels have excellent biocompatibility and improved anticancer cytotoxicity to A549 cells after loading drug DOX.     

防紫外线超疏水织物涂层构筑及性能

以羟基氟硅油、季戊四醇三丙烯酸酯(PETA)为原料,制备了含双键的聚氨酯,在整理液中添加紫外线吸收剂(UVA400)和纳米二氧化硅颗粒,以提高涂层的紫外线防护效果和表面粗糙度,通过紫外光引发双键自由基聚合构筑防紫外超疏水织物涂层,并对材料进行了FTIR、SEM、疏水性及紫外线防护性能测试。结果表明:羟基氟硅油和PETA引入到了聚氨酯分子链中;织物表面具有微纳米状凸起,形成了粗糙的表面涂层。当整理液固体组分中w(SiO2)=15%,w(UVA400)=1.5%时,涂层织物的接触角为154?,滚动角为9?,紫外线防护系数(UPF)为72,紫外线A(UV-A)波段的透过率为2.96%,具有超疏水和紫外线防护性能;涂层织物经120h加速老化实验后,接触角为155?,UPF为117,UV-A波段的透过率为2.68%,具有良好的耐久性。     

Influence of low‐temperature plasma conditions on wicking properties of PA/PU knitted fabric

Plasma surface treatment has been extensively applied in the textile industry for the modification of polymer materials. In this study low‐temperature plasma (LTP) is used for surface treatment of polyamide/polyurethane (PA/PU) knitted fabric. The envisaged plasma effect is an increase in the surface energy of the treated textile, leading toward improved hydrophilic properties. The knitted fabric was treated by LTP using three non polymerizing gases: oxygen, air, and carbon dioxide. After plasma treatment, wettability of samples was tested through their wicking properties measuring capillary rise after water bath contact. The PA/PU knitted fabric samples treated with different plasma gases exhibited different hydrophilic performances. The influence of plasma variables (discharge power, time, pressure) was investigated. Although the chemical characteristics of elastan (PU) and nylon (PA) threads are different, the study has demonstrated that plasma treatment can in the same time alter the surface‐wetting behavior of both the components of the knitted fabric. It was also shown how these treatments can be regulated to produce the desired level of hydrophilicity dependently on the request application. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

Anticorrosion and electromagnetic interference shielding behavior of candle soot-based epoxy coating

This article presents candle soot (CS) as anticorrosion coating material for mild steel (MS) in 3.5 wt % of NaCl solution using potentiodynamic polarization and electrochemical impedance spectroscopy. CS is easily available, low-cost material, and characterized by using X-Ray diffraction (XRD), Raman spectroscopy, UV–vis spectroscopy, Fourier-transform infrared (FTIR), and scanning electron microscopy (SEM). CS is superhydrobhobic in nature that helps to prevent corrosion by repelling water molecules from MS surface. The electrochemical results confirmed the prevention in corrosion process for MS using candle soot-epoxy (CS-EP) based anticorrosion coatings. The CS-based coatings displayed outstanding barrier properties in 3.5 wt % of NaCl solution in comparison to the neat EP coating. Different candle CS-EP coating combinations were tested that exhibited excellent corrosion inhibition performance with highest protection increased up to 98.45% at 0.2 wt % of CS. The surface morphological studies were used to analyze the MS surface conditions in absence and presence of CS-EP coating in 3.5 wt % of NaCl solution. CS-EP admixtures were also tested for their shielding effectiveness in the frequency range of 8.2–12.4 GHz and it has been found that on incorporation of 0.2 wt % of CS in EP resin total shielding effectiveness (SE_T) increased to −5.3 dB as compared to −0.33 dB for neat EP. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 137, 48675.     

Lightweight,robust, porous heterocyclic para-aramid aerogel hollow fibers for multifunctional applications

In nature, many fibers with warmth-retention properties, such as the hair of polar bears and rabbits, both have a hollow cross-section structure. The static air in fiber cavities can effectively inhibit heat conduction and serve as an effective thermal insulator. In this work, the high-performance heterocyclic para-aramid polymer was selected as the spinning solution, and aerogel hollow fiber was prepared by coaxial wet spinning and freeze-drying techniques. The effects of spinning solution concentration and lyophilized solvent on the micromorphology, mechanical properties, and specific surface area of heterocyclic para-aramid aerogel hollow fiber (HPAAHF) were systematically studied. The produced HPAAHF possessed excellent mechanical properties (tensible strength ~3.85 MPa), high specific surface area (~ 260.90 m² g⁻¹), and lightweight advantages. The thermal conductivity of HPAAHF was only 0.0278 W m⁻¹ K⁻¹, indicating its excellent thermal insulation properties. The aerogel fabric exhibited outstanding flame retardancy properties, with a total heat release of only 0.7 MJ m⁻² in the cone calorimetric experiment, making it a self-extinguishing fabric. In addition, phase change material was injected into the hollow structure to obtain aerogel-phase change material composite fibers, which exhibited great energy storage prospects. As a result, the high-performance heterocyclic para-aramid polymer-based aerogel hollow fiber was successfully prepared and had multifunctional applications in thermal insulation, flame retardancy, and heat energy storage fields.     

A Novel Route for the Preparation of Silver Loaded Polyvinyl Alcohol Nanogels for Wound Care Systems

This study is aimed at the development of a composite wound dressing containing nanosilver loaded polyvinyl alcohol (PVA) nanogels. The PVA nanogels were prepared by fructose induced reduction of silver nitrate within PVA gel to develop nanosilver nanogel (nGel). The influence of various synthesis parameters on PVA nanogel formation was investigated. The particle size of the nanogels, as evaluated by transmission electron microscopy was observed to be in the range of 10–50 nm. Glycerol was added to the nGel system and this composition, nGel/Glc, was coated on cotton fabric to develop a composite wound dressing. The cumulative release of silver from the dressing was found to be ～36% of the total loading after 48 h. Even at such low concentrations, high antibacterial efficiency was achieved against both gram positive and gram negative bacteria. In vivo wound healing studies were carried out over a period of 21 days on full-thickness skin wounds created on Swiss albino mice. Fast healing was observed in nGel/Glc treated wounds with minimum scarring, as compared to other groups. These results suggest that nGel/Glc based dressing material could be promising candidates for wound dressing applications.     

POSS/有机硅改性聚丙烯酸酯无氟防水剂的合成与应用研究

通过无皂乳液聚合技术合成了POSS/有机硅改性聚丙烯酸酯无氟防水剂,并将其应用于棉织物整理。考察了软硬单体配比对乳液、乳胶膜及其应用性能的影响。利用傅里叶红外光谱(FT-IR)和傅里叶红外光谱(DLS)对聚丙烯酸酯的结构及乳胶粒的粒径大小进行了表征,利用伺服材料多功能高低温控制试验机、柔软度仪、SEM对整理织物的应用性能及表面形貌进行了表征。结果表明：当m(BA):m(MMA)为6:4时,单体的转化率最大为96.97%,乳液的凝胶率为0.14%,乳胶粒的粒径最小为104.8 nm,乳胶膜对水的接触角最大可达114.3?,并具有优异的耐水性。整理棉织物表现出优异的力学性能和良好的柔软度,其对水的接触角可达161?。SEM结果表明棉织物纤维表面存在功能化POSS纳米颗粒。无氟防水剂赋予棉织物纤维表面低的的表面能和一定的粗糙结构,从而使整理棉织物表现出超疏水性能。     

Moisture absorption capacity of polyamide 6,6 fabrics surface functionalised by chitosan-based hydrogel finishes

The present study aims at investigating the moisture absorption capacity of polyamide 6,6 fabrics when their surface is functionalised by chitosan-based hydrogels. For the finishing procedure, bulk hydrogels of chitosan (CS) with different contents of embedded thermosensitive microparticles of poly(N-isopropylacrylamide-co-acrylic acid) (PNIAA) were used. In practice, hydrogel incorporation into the fabric surface layer was achieved by crosslinking primary amine groups of chitosan with the end amine groups of polyamide, using the natural crosslinker genipin. Among other analytical techniques, Scanning Electron Microscopy (SEM) was used to characterize the surface morphology of both hydrogel and fabric samples, Differential Scanning Calorimetry (DSC) to determine the Lower Critical Solution Temperature (LCST) of PNIAA, and X-ray Photoelectron Spectroscopy (XPS) to analyse the fabric surface chemical composition. The fabric moisture contents were determined by weight measurements at different temperatures and relative humidity values (RH). Liquid porosimetry, water vapour transmission (WVT) and dynamic wetting measurements were also performed to assess the fabric pore volume distribution, permeability and wetting times, respectively. It was found that the moisture absorbed by the functionalised polyamide fabrics can be regulated at different conditions of temperature and relative humidity according to the PNIAA/CS ratio in the hydrogel. For example, at 40 °C (i.e. above the PNIAA LCST) and even at high RH (85%), the higher the PNIAA/CS ratio was in the incorporated hydrogel, the lower were the moisture contents of the functionalised fabrics, compared to the reference. In all cases, the presence of CS increased significantly the polyamide fabric wetting times.     

Fabrication and characterization of bioactive calcium silicate microspheres for drug delivery

The calcium silicate (CaSiO₃, CS) microspheres with diameter of 75–100 μm were fabricated by a spray-drying method. A new bone-like apatite layer fully covered the surface of the fabricated CS microspheres after soaking in simulated body fluid (SBF), suggesting the excellent activity of the material in inducing apatite deposition. The ionic extracts of CS microspheres promoted the proliferation of human osteoblast-like cells (MC3T3-E1). In addition, the porous structures of the CS microspheres resulted in favorable drug loading and sustained release property. Our study indicates that the fabricated multifunctional CS microspheres are a promising drug delivery system as an injectable bioactive filling material for bone-regeneration.     

Fabrication of robust self-cleaning superhydrophobic coating by deposition of polymer layer on candle soot surface

A facile and inexpensive way have been developed to fabricate robust self-cleaning superhydrophobic coating by depositing polymer layer on candle soot (CS) surface using dip coating method. The stability and robustness of the CS deposited superhydrophobic surface is much weaker due to weak interaction and nonchemical bonding with the substrate. We introduced a thin layer of polystyrene, polyethylene, polypropylene (PP), and polyvinylidene fluoride on CS surface in order to improve its mechanical properties. The fabricated surfaces with the use of respective polymers exhibited water contact angles of nearly 170, 174, 175, and 171° with sliding angles of 2, 1, 1, and 3°, respectively. Although, all the polymers used in this work exhibited excellent superhydrophobic and self-cleaning surface property, we found that the PP deposited CS surface exhibit better stability against water jet hitting and water drop impact tests. The PP deposited CS surface almost maintained their surface properties even after 50 cycles of sandpaper abrasion and 20 cycles of adhesive tape peeling tests. The mechanical durability tests confirmed that PP is a better polymer to improve the long-term durability of CS surface. Therefore, this simple, time saving, and inexpensive method for fabricating superhydrophobic coating can be used for potential industrial application.     

Functionalization of wool fabric with phase‐change materials microcapsules after plasma surface modification

The use of microcapsules has increased in several different areas, namely, textile applications. They have been used as a possible means of introducing new properties, namely, in medical care by antibiotics, skin moisturizers, and other drugs and for thermal comfort. In this study, we examined the influence of dielectric barrier discharge (DBD) plasma treatment on the adhesion of phase‐change material (PCM) microcapsules on wool fabric. Several experimental techniques were used to evaluate the wool surface modification after plasma treatment and the influence of the microcapsules' resistance to washing conditions, namely, the determination of the static and dynamic contact angles, surface energy, and adhesion work; X‐ray photoelectron spectroscopy; Fourier transform infrared spectroscopy; differential scanning calorimetry; and scanning electron microscopy. Chemical and physical characterization of the wool fiber in the fabric confirmed significant surface modification. The plasma treatment greatly increased the hydrophilicity, surface energy, and adhesion work of the wool fabric; this proved that more microcapsules were adsorbed on the fabric and more microcapsules remained on the fabric surface after the washing procedures. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

PDA/DTMS-纳米TiO2对蚕丝织物自修复超疏水整理

为了赋予蚕丝织物自清洁与防污性能,首先利用多巴胺(DA)在CuSO₄/H₂O₂氧化体系下快速聚合形成聚多巴胺(PDA)沉积在蚕丝织物表面,再通过十二烷基三甲氧基硅烷(DTMS)改性的纳米TiO₂对沉积PDA的织物进行超疏水功能整理。通过FTIR、SEM、XPS、接触角测量仪对改性前后蚕丝织物的化学组成、表面微观结构、疏水性能进行表征,测试了改性蚕丝织物的自清洁与防污性、疏水自修复性和抗紫外线性能。结果表明,PDA/DTMS-纳米TiO₂改性蚕丝织物表面具有分布均匀的微纳结构,且与原蚕丝织物相比,织物表面自由能下降;其水接触角为156°、滚动角为5°,防紫外线系数(UPF)为75.81,具有良好的防污自清洁能力和抗紫外线性能,与原蚕丝织物相比透气性略有下降;经O₂等离子体10次的刻蚀-修复循环或1200次机械磨损-修复循环后,蚕丝织物的疏水修复率均>96%,耐环境损伤的自修复效果明显。此外,洗涤25次后,PDA/DTMS-纳米TiO₂     

Oil–water separation capability of superhydrophobic fabrics fabricated via combining polydopamine adhesion with lotus‐leaf‐like structure

By the combination of dual bionic on the superhydrophobicity of lotus leaf and the bioadhesion of mussel adhesive protein, the nanoparticles were strongly immobilized onto the surface of cotton fabric to form superhydrophobic and superoleophilic coating. The as‐prepared fabric can be used as effective material for separating various oil/water mixtures. The separation efficiency can reach 99.0%, 97.6%, 98.1%, 96.0%, 94.2%, and 94.5% for toluene/water, n‐hexane/water, chloroform/water, paraffin oil/water, linseed oil/water, and crude oil/water mixtures with volume ratio of 1 : 4, respectively. In addition, the obtained fabric still kept stable superhydrophobicity and high separation efficiency for oil/water mixtures after using repeatedly for 90 cycles or ultrasonic treatment. They also exhibited excellent chemical durability in harsh conditions of strong acidic and alkaline solutions. Owning to high separation efficiency, stable recyclability, low cost, scalable fabrication, and excellent durability, the as‐prepared fabric can be considered as promising material for the separation of oil/water mixtures. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42614.     

Fabrication and properties of PEI/APP layer-by-layer coated ramie fabric combined with low-temperature plasma treatment

The present work demonstrates a surface pretreatment of reducing assembly layers for flame retardant modification of ramie fabric used by layer-by-layer (LbL) assembly. In order to achieve this goal, low-temperature plasma (LTP) pretreatment was chosen. Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and scanning electron microscope (SEM) were used to confirm the effect of LTP pretreatment on polyethylenimine/ammonium polyphosphate (PEI/APP) flame retardant coating constructed on the surface of ramie fabric using LbL assembly. The thermal property and flame retardancy of PEI/APP coated ramie fabrics were analyzed by TG, LOI, UL94 vertical burning, and cone calorimeter tests. The results indicated that the decomposition rate of ramie fabrics was reduced and the char forming ability at high temperature was improved by PEI/APP coating on the ramie surface. Its LOI increased markedly to 30.6% and ramie fabric achieved self-extinguishing effect. Meanwhile, LTP-O₂-(PEI/APP)₂₀ ramie fabric exhibited the low flammability and high fire safety. It was proved that LTP pretreatment under oxygen atmosphere could endow ramie fabric with better flame retardancy due to more PEI/APP adsorbed on its surface. These findings have significant implications for the application of LTP pretreatment to flame retardant modification of ramie fabric by LbL assembly.     

纳凝胶的制备、性能及应用进展

纳凝胶（nanogels）具有比表面积大、负载量高、分散稳定、刺激响应性等优点,在生物医药、化工和新材料等领域有广阔的应用前景。本文对制备纳凝胶的物理和化学交联等常规方法及微流控、电喷射、电芬顿法等新方法进行了综述,阐述了各种方法的制备原理与优缺点;对纳凝胶的生物相容性和降解性、溶胀性、稳定性等基本性能作了介绍,特别对其刺激响应性作了重点调研;并对其在药物控释、生物传感器、酶固定化、分子成像、增塑剂、水处理等方面的应用研究进展进行了归纳。最后结合纳凝胶在制备方法及应用中存在的实际问题,指出新型凝胶基质、纳凝胶表面改性及绿色可控制备方法等是今后纳凝胶研究的重要方向。     

Enhancement in electrical conductive property of polypyrrole‐coated cotton fabrics using cationic surfactant

Recently, great efforts have been made to gain highly conductive fabrics for smart textiles and flexible electromagnetic shielding materials. Different from the conventional chemical synthesis method, fibrillar polypyrrole was synthesized on the cotton fabrics via a simple chemical polymerization process with micelles of cationic surfactant (cetyltrimethylammonium bromide, CTAB) as soft template. The modified cotton fabric exhibited excellent electrical conductivity and electromagnetic interference shielding effectiveness due to the formation of fibrillar polypyrrole on the fiber surface. Electrical conductivity of fabric surface were studied by four‐probe resistivity system. The highly conductive fabric with surface conductivity of 5.8 S cm^?1 could be obtained by changing cationic surfactant concentration. The electromagnetic interference shielding effectiveness (EMI SE) of the modified fabrics was evaluated by the vector network analyzer instrument. Compared with the sample without using surfactant, the EMI SE value of PPy‐coated cotton fabrics increased by 28% after using 0.03 M CTAB as soft template. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43601.     

Nanogels comprising reduction-cleavable polymers for glutathione-induced intracellular curcumin delivery

In this study, we prepared nanogels of a disulfide-cleavable polymer via polyionic complexation and genipin cross-linking and evaluated their reduction-triggered intracellular curcumin (Cur) delivery. These nanogels were stable at physiological conditions due to the formation of genipin cross-linking and helical PLL/PDC complexes and would swell/dissociate at acidic and reductive conditions due to the dissociation of PLL/PDC complexes and cleaving of disulfide bonds. The cellular uptake and intracellular release of Cur-loaded nanogels were demonstrated by tracking the fluorescent Cur and in vitro drug release studies, confirming the triggered release of Cur at acidic and reductive microenvironments in cells. The MTT, TUNEL staining, and Caspase-3 activity assays showed that the Cur-loaded nanogels exhibited higher cellular proliferation inhibition toward U-87 MG cells than free Cur, whereas the blank nanogels exhibited low cytoxicity. The results highlight the potential of functional nanogels prepared by polyionic complexation and cross-linking as a smart nanocarrier for drug delivery.     

Nanogel-modified polycaprolactone microfibres with controlled water uptake and degradability

In this work we prepared composite poly(caprolactone) (PCL) microfibres decorated with temperature-sensitive poly(N-vinylcaprolactam) nanogels by an one-step electropsinning process. Microfibres with variable internal structure were prepared by using two different solvent systems: methanol/toluene (Me/Tol) and chloroform/dimethylformamide (Ch/DMF). Our experimental data shows that the nature of the solvent mixtures allows obtaining microfibres with different morphologies: Microfibres with nanogels on the fibre surface (Me/Tol) and microfibres with nanogels in the fibre interior (Ch/DMF). The morphology of composite fibres was visualized by scanning electron microscopy (SEM) and their properties investigated by differential scanning calorimetry (DSC), thermo-gravimetric analysis (TGA) and contact angle measurements. The results show that combining hydrophobic poly(caprolactone) with hydrophilic nanogels leads to microfibres exhibiting controlled swelling in water. Additionally, the thermo-sensitive properties of the nanogels are maintained whether they are on the surface or inside of the fibres. The presence of nanogels in the fibre structure also allows regulating their degradability.     

PET非织造布等离子改性及抗菌性能研究

采用低温氧等离子体处理聚对苯二甲酸乙二酯(PET)非织造布接枝丙烯酸(AA)后,再接枝壳聚糖,探讨了氧等离子体参数对接枝AA后PET亲水性的影响,以及接枝壳聚糖后其PET非织造布抗菌性能的变化。结果表明:低温氧等离子体处理PET非织造布后,其纤维表面粗糙度增加,接枝AA后PET亲水性提高。低温氧等离子体处理PET非织造布接枝AA改性的最佳条件为:工作压强30 Pa,放电功率40 W,处理时间2 min。接枝壳聚糖后,PET非织造布具有抑菌性能,对大肠杆菌和金黄色葡萄球菌有明显的抑菌效果。