Wet Property Research Articles

Effect of demineralized water on the silanization reaction and the performance properties of green tire tread compound

AbstractTire industries seek advancements in technologies ranging from novel constructions to new material systems for fuel efficiency. The chemical formulation of tread compounds and their processing conditions can significantly affect tire performance for key attributes, including rolling resistance, wet traction, and wear resistance. Adding demineralized water (DMW) molecules might enhance the silanization reaction between silane and silica filler surface via improved hydrolysis and condensation, resulting in a better silanization reaction. DMW was sprayed on a silica surface before mixing, incorporated with TESPD silane into S‐SBR/BR tire tread compound, and mixed in an internal mixer. The effects of an increase in the DMW content on compound processability, cure characteristics, filler dispersion, dynamic properties, and mechanical properties were investigated. Adding the water‐treated silica into the compound lowered the heat generation during mixing, lowered the dump temperature, lowered the tan δ (E″/E′) at 60°C, and increased the wet grip property by retaining the abrasion resistance compared with the control. The enhancement of filler dispersion was visualized via scanning electron microscope images. Reaction kinetics concerning the addition of water and the effect of the pH of water on the silanization reaction is also discussed using HPLC analysis.

Exploring the Influences of BaO Amount on the Wettability and Mechanical Behavior of Vitrified Bond Diamond Composites.

In recent years, the vitrified bond diamond grinding wheel has been applied widely in automotive, aerospace and machine tools of manufacturing industries. However, the main problems of low intensity and poor wettability between the vitrified bond and diamond abrasive limit its further application. In this study, BaO was added into the basic SiO2-B2O3-Al2O3-R2O vitrified bond system, and the impact of BaO on the wettability, thermal and mechanical behavior of vitrified bond and vitrified bond diamond composites was systematically discussed, respectively. The test indicated that when the vitrified bond containing BaO of 6 wt.% was sintered with diamond abrasive at 750 °C, a continuous barium feldspar phase transition layer between diamond abrasive and the bond was generated, which ameliorated the wet property of the bond-diamond abrasive. The contact angle varied from 59° on the blank sample to 35°, and the expansion coefficient changed from 6.24 × 10-6/K to 5.30 × 10-6/K. The Rockwell hardness and flexural strength of the vitrified bond diamond composites achieved the peaks of 117.5 MPa and 113.6 MPa, respectively, which increased by 20.2% and 16.5% compared with that of sample without the addition of BaO.

Influence of honeycomb structures on fluids transmission and heat retention properties; An initiative towards stretchable weaves

The aesthetics and functionality of honeycomb woven assemblies qualifies them for a range of applications expanding across home textiles, fashion, functional apparels, and technical products. Researchers have explored honeycomb assemblies with the focus on shrinkage, sound absorption, thermal conductivity, and heat protection properties analysis via variation in their cell sizes. However, very minimal research is found on analysis of honeycomb woven fabric assemblies’ thermal comfort characteristics by employing different weft insertion sequence and materials (cotton and stretchable yarns). This study reflects the thermal conductivity, dry fluid transmission (air permeability), wet fluid transmission (moisture management), and stiffness attributes of twelve stretchable honeycomb woven assemblies consisting of single ridge, double ridge, and brighton honeycomb weave structures along with different weft sequences of cotton and Type 400 (T-400) stretch yarns. Characterization data showed that single ridge honeycomb structure supports the highest dry fluid transmission property; however, brighton honeycomb offers the highest heat retention property. Double ridge honeycomb highlights the capability of the highest wet fluid transmission property, and brighton honeycomb has immense stiffness. Statistical analysis (ANOVA) also showed that honeycomb structures, weft yarn sequence and material have a statistically significant impact on thermal conductivity and fluid transmission behaviors with p-values less than 0.05.

Rapid and portable mid-infrared analysis of wet sediment samples by a novel “filter-press” attenuated total reflectance method

Mid-infrared (MIR) analysis of wet sediments or soils usually requires freezing and drying, adding considerable analysis time and cost, and promoting changes in chemical properties. A novel attenuated total reflectance (ATR) mid-infrared (MIR) method was developed to enable analysis of non-processed, aqueous sediments. Wet sediment samples from the Coorong Lagoon, South Australia, were subjected to laboratory analysis for physical and chemical properties, our new filter-press ATR method, and conventional ATR and diffuse reflectance (DRIFT) analysis of dried samples. For ATR on wet sediments, samples were pressed onto the ATR crystal with a filter-paper backing and scanned. The spectra were analyzed by principal components analysis (PCA) and partial least squares regression (PLSR) to develop multivariate models for total organic carbon (TOC). ATR spectra of as-received wet sediments were poor due to water absorption features, but filter-pressing reduced these and greatly enhanced the solids spectral component. The filter-pressed PLSR cross-validation for TOC resulted in an R2 = 0.89 and RMSECV = 0.78%. Prediction accuracies were similar to freeze-dried ATR samples and far more accurate than testing wet samples without filter-pressing. Our findings confirmed the filter-press ATR method as proof-of-concept and showed that it has the potential to remove one of the major barriers to in-field application of MIR techniques, the high and variable amounts of moisture levels commonly present in many environmental samples. Extension of the filter-press ATR method to a wider range of analytes may enable it to rapidly acquire moist or wet sediment and soil property data while in the field.

Bioadhesive Microcarriers Encapsulated with IL-27 High Expressive MSC Extracellular Vesicles for Inflammatory Bowel Disease Treatment.

Mesenchymal stem cell (MSC) therapy is a promising candidate for inflammatory bowel disease (IBD) treatment, while overcoming the limitations of naive seeding cells function and realizing efficient intestinal targeting remains a challenge. Here, a bioadhesive microparticle carrying interleukin-27 (IL-27) MSC-derived extracellular vesicles (MSCIL-27 EVs) is developed to treat IBD. The MSCIL-27 EVs prepared through lentivirus-mediated gene transfection technology show ideal anti-inflammatory and damage repair function. By encapsulating MSCIL-27 EVs into dopamine methacrylamide-modified hydrogel, a bioadhesive EVs microcarrier via microfluidic technology is fabricated. The resultant microcarriers exhibit ideal MSCIL-27 EVs sustained release effect and effective wet adhesion property. Furthermore, the therapeutic potential of MSCIL-27 EVs-loaded microcarriers in treating IBD is demonstrated. Through giving IBD rats a rectal administration, it is found that the microcarriers can firmly anchor to the surface of colon, reduce the inflammatory response, and repair the damaged barrier. Therefore, the bioadhesive MSCIL-27 EVs-loaded microcarriers provide a promising strategy for the biomedical application of MSC-derived EVs, and broaden the clinical potential of MSC therapy.

EFFECT OF ADDITION OF WET-STRENGTH AGENT ON TENSILE STRENGTH OF PAPER

Wet-strength paper production is of great significance due to its prominent importance in everyday consumer activities. Recently, market demands for paper with specific properties and purposes are increasing. Production of these paper types is very challenging for the manufacturer since they have to meet very specific demands. Wet-strength paper products include bags that come in contact with moisture and wet products, hygienic and kitchen towels, paper towels, packaging products (packages for liquids, aseptic dishes, and a variety of packaging for food), and other special purposes items (tea bags, coffee filters, paper money, etc.) Throughout this research, the focus was on the effects a wetstrength agent has on the tensile strength of paper. The wet strength property of paper is the ratio between the strength of paper in the wet and dry state. The strength in the dry state comes from the hydrogen bonds present in natural cellulose, while the strength of paper in the wet state requires waterproof (covalent) bonds created by the use of a wet strength agent. The wet strength agent used is a cationic PAE resin. The aim of the work is to determine the optimal amount of agent needed in relation to the required value of the tensile strength property of the paper. The investigation of these influences was carried out on Semi Extensible Standard Kraft type of paper in Natron-Hayat.

Regulation of the fabric wet adhesion property through structural design of desirable scale: A theoretical suggestion

It is a universal phenomenon existing in both manufacture and everyday life that fabrics tend to adhere under wet condition. The phenomenon is closely related to the interaction of the fabric surface structure and the liquid. Among the complex structures and numerous varieties of fabrics, the features of typical fabric structures are employed to establish a geometrical model (including structural configuration of spherical protrusion, cylinder, loop, and pore) in order to investigate wet adhesion property under the existence of massive liquid media. Through mechanical analysis on material-liquid bridge system (consisting of fabric material, liquid bridge adhering to the material, and the solid-liquid interface), a quantitative computational theoretical model is built with parameters including critical distance [Formula: see text], radius of the structure R*, apparent receding contact angle [Formula: see text], wetted sphere angle [Formula: see text], and so on, finding the rules and proposing a series of preferred ranges of regulating structural parameters to effectively achieve desirable fabric wet adhesion property in different circumstances. The research findings could be applied to the scientific prediction and on demand regulation of fabric wet adhesion property. They are of great significance with regard to improving the convenience of fabric wet processing, application properties under wet environments, apparel health and comfort for human body, and so on.

Water-induced shape memory cellulose nanofiber-based nanocomposite membrane containing lignin with quick water response and excellent wet mechanical property

Cellulose-based water-responsive shape memory materials have received widespread attention due to their wide range of sources, high response rate, and environmental friendliness. However, fast responsive shape memory polymers (SMPs) tend to lose wet strength due to excessive hydration. Thus, it greatly limits the application range of cellulose-based water-responsive shape memory materials. To address this issue, in this work, a cellulose nanofiber (CNF) nanocomposite membrane with high water-induced shape memory properties was successfully prepared containing polyvinyl alcohol (PVA) and lignin (LIG). Citric acid (CA) was used as the cross-linking agents. Changes in the content ratio of CNF to PVA and the amount of LIG added will change the crosslinked network structure of the CA/LIG/PVA/CNF membrane, leading to changes in the microstructure, water responsiveness and mechanical properties of the membrane. With the addition of LIG, the fracture surface of the microstructure will orient along longitudinal direction and form a densely packed layered structure. The increase content ratio of CNF to PVA can improve the compatibility of each component. The water-induced shape memory recovery rate of the nanocomposite can reach 100% within 4 s. In the dry state, the maximum tensile strength of the film can reach 138.0 MPa, and the maximum tensile modulus of the film can reach 9.0 GPa. After wet swelling, the highest tensile strength and tensile modulus are up to 60 MPa and 0.7 GPa, respectively. The CNF nanocomposite film has excellent performance in blocking ultraviolet and the transmittance value of the membrane is below 8% in the ultraviolet region of 200–400 nm. Hence, the resultant CA/LIG/PVA/CNF membrane will have potential applications in smart science and the provide a framework for developing a cellulose-based shape memory polymer.

Injectable Hydrogel with Ultrafast In Situ Reforming Properties

AbstractShearing‐thinning injectable hydrogels, with a fixed 3D network structure, have significant potential for application in soft and hard tissue defect repair, drug delivery, wound dressings, etc. However, these hydrogels often exhibit poor in situ reforming ability in wet and underwater environments. In this study, a hydrogel with ultrafast in situ reforming ability in wet and underwater environments is prepared using modified sodium alginate–polyvinyl alcohol–dopamine. This hydrogel, with a double dynamic chemical crosslinking network, exhibits good in situ and ex situ self‐healing abilities owing to the wet adhesion property of dopamine and the underwater rebuilding property of borate ester bonds. The strength of in situ self‐healing is restored to 90.1% and 110.2% of the original strength and that of ex situ self‐healing is restored to 101.3% and 123.9% of the original strength after 6 min of healing in water and phosphate buffer solution environments, respectively. The in situ reforming efficiency of the hydrogel is reported to be 86.6% within 5 min of being injected into the liquid environment owing to the contribution of in situ self‐healing and ex situ self‐healing. In addition, the proposed hydrogel has good cell compatibility. Therefore, it can be widely used as a biomaterial.

Impact of α‐cellulose as a green filler on physico‐mechanical properties of a solution grade styrene‐butadiene rubber based tire‐tread compound

AbstractPhysico‐mechanical and dynamic mechanical properties of typical solution grade styrene‐butadiene rubber (S‐SBR) and polybutadiene rubber (PBR) based tire‐tread compound were investigated by partially replacing highly dispersible (HD) silica with naturally occurring α‐cellulose. Fourier transform infrared spectrum detected abundance of hydroxyl group in α‐cellulose, which has created keenness to investigate its reinforcement characteristics in an S‐SBR and PBR based compound. Scanning electron microscope and transmission electron microscope were employed to investigate the microstructure and dispersion of α‐cellulose at higher magnification. Thermo‐gravimetric analysis was performed to understand the degradation behavior of α‐cellulose. Differential scanning calorimeter was engaged to detect phase transition and degree of purity of α‐cellulose. An increase in cure rate was observed with partial replacement of HD silica by α‐cellulose. The cure rate index was increased by 13% over control one at 10% replacement of silica with α‐cellulose. It was noticed that at an optimum level of replacement (10%), α‐cellulose containing compounds exhibited lower viscoelastic energy dissipation (both loss modulus [E″] and loss tangent [tan δ]) at the slight expense of tensile moduli. Beside these, substitution of silica with α‐cellulose found to have no effect on wet grip property of the compounds.

Oxidation Chemistry of Catechol Utilized in Designing Stimuli-Responsive Adhesives and Antipathogenic Biomaterials.

Mussel foot proteins (Mfps) contain a large amount of the catecholic amino acid, DOPA, allowing the marine organism to anchor themselves onto various surfaces in a turbulent and wet environment. Modification of polymers with catechol imparts these materials with a strong, wet adhesive property. The oxidation chemistry and oxidation state of catechol are critical to the design of synthetic adhesives and biomaterials. In this Mini-Review, the effect of catechol oxidation state on adhesion, oxidation-mediated catechol cross-linking, and the generation of reactive oxygen species (ROS) during catechol oxidation are reviewed. Finally, the tuning of catechol oxidation state in designing stimuli-responsive adhesives and the utilization of ROS byproducts for antimicrobial and antiviral applications are reviewed.

Self-Assembly and Mechanical Properties of Engineered Protein Based Multifunctional Nanofiber for Accelerated Wound Healing.

The present work reports a new route for preparing tunable multifunctional biomaterials through the combination of synthetic biology and material chemistry. Genetically encoded catechol moiety is evolved in a nanofiber mat with defined surface and secondary reactive functional chemistry, which promotes self-assembly and wet adhesion property of the protein. The catechol moiety is further exploited for the controlled release of boric acid that provides a congenial cellular microenvironment for accelerated wound healing. The presence of 3,4-dihydroxyphenylalanine in the nanofiber mat act as a stimulus to trigger cell proliferation, migration, and vascularization to accelerate wound healing. Electron paramagnetic resonance, NMR, FTIR, and circular dichroism spectroscopy confirm the structural integrity, antioxidant property, and controlled release of boric acid. Fluorescent and scanning electron microscopy reveals the 3D architecture of nanofiber mat, which favors fibroblast growth, endothelial cell attachment, and tube formation, which are the desirable properties of a wound-healing material. Animal studies in the murine wound healing model assert that the multifunctional biomaterial significantly improve re-epithelialization and accelerate wound closure.

Field Design for Enhancing Water Productivity in Waterlogged Areas with Efficient Water Harvesting and Farming System

Low productivity in waterlogged ecosystem is due to excess and deficit water stress during wet season and dry season, respectively. Good quality surface water abundantly available in the ecosystem can be harvested and used efficiently in farming system for enhancing land and water productivity. For deep waterlogged areas (ponding depth > 1 m), improved rice–fish integrated farming system is suggested. Land modifications for this include excavating soil from a pond refuge (7% area) and two side trenches (10% area), and constructing wide dykes (23% area) on four sides of the system. Water harvesting up to potential level and growing of water loving crops (water chestnut, deep water rice) is suggested. Emphasis is given to grow dry season rice with irrigation requirement of 572.4 mm (dry season rainfall not considered) for the test soil with low seepage percolation loss (0.47 to 1.93 mm day−1 during November to April). This was due to high clay content (52 to 55%) having wet swelling property. Dry season rice occupying 6000 m2 area in 1 ha rice–fish system area may demand 3434 m3 additional water considering residual harvested water (200 mm). A supporting farm pond (45 m × 40 m × 3 m) located nearby may provide this demand including pisciculture and dyke crops. For moderately deep water logged area (ponding depth 0.5 to 1 m), adoption of wide spaced creeper crop, drip irrigation and early seedling raising are suggested for water saving in dry season. Water requirement for 1 ha dry season pumpkin crop is 4200 m3. Supporting farm pond (45 m × 40 m × 3 m) is required for meeting the irrigation demand of pumpkin, dyke crops and pisciculture in farm pond.

Lignocellulose Enabled Highly Transparent Nanopaper with Tunable Ultraviolet-Blocking Performance and Superior Durability

Lignin-containing cellulose nanopaper (LCNP) has emerged as a new generation of sustainable film for packaging and electronics. While compared with pure cellulose nanopaper (CNP), it still exhibits relatively lower transparency or declining mechanical performance, which greatly hinders its practical application. To address these issues, we reported a highly available route involving a TEMPO-mediated oxidation method followed by a homogenization process to prepare lignin-containing cellulose nanofibers (LCNFs) based on a lignocellulose material and then directly processed the LCNFs into a dense film (LCNP) via a mature papermaking process. Due to small fibers produced by this method, the resultant LCNP exhibits an ultrahigh visible light transmittance (∼91%) close to CNP. Moreover, the high lignin reservation (∼16%) endows the nanopaper excellent UVA-blocking efficiency (∼68%) and better environmental durability than CNP. The retaining lignin was found to serve as a reinforcing agent filled in LCNP, resulting in a significant improvement on toughness, wet mechanical property, and thermal stability. Overall, this fully biobased LCNP with outstanding performance is a promising candidate to replace conventional petroleum-based materials in the fields like flexible electronics, packaging, and protective products.

Balancing the decomposable behavior and wet tensile mechanical property of cellulose-based wet wipe substrates by the aqueous adhesive

With the current global outbreak of novel coronaviruses, the fabrication of decomposable wet wipe with sufficient wet strength to meet daily use is promising but still challenging, especially when renewable cellulose was employed. In this work, a decomposable cellulose-based wet wipe substrate is demonstrated by introducing a synthetic N-vinyl pyrrolidone-glycidyl methacrylate (NVP-GMA) adhesive on the cellulose surface. Experimental results reveal that the NVP-GMA adhesive not only significantly facilitates the chemical bonding between cellulose fibers in the wet state, but also increase the surface wettability and water retention. The as-fabricated cellulose-based wet wipe substrate displays a superb water retention capacity of 1.9 times, an excellent water absorption capacity (completely wetted with 0° water contact angle), and a perfect wet tensile index of 3.32 N.m.g−1. It is far better than state-of-the-art wet toilet wipe on the market (non-woven). The prepared renewable and degradable cellulose-based substrate with excellent mechanical strength has potential application prospects in diverse commercially available products such as sanitary and medical wet wipes.

Thermal and Wet Comfort of Modified Linen Clothing in Humid Environment

Kuang, C., 2020. Thermal and wet comfort of modified linen clothing in humid environment. In: Yang, Y.; Mi, C.; Zhao, L., and Lam, S. (eds.), Global Topics and New Trends in Coastal Research: Port, Coastal and Ocean Engineering. Journal of Coastal Research, Special Issue No. 103, pp. 1144–1148. Coconut Creek (Florida), ISSN 0749-0208.It is important that the moisture permeability of clothing maintain the thermal balance of the human body in humid environment or at the stage of motion. In this paper, the dressing comfort difference between the long sleeve shirt made of modified treatment linen fabric and that made of unmodified linen fabric was analyzed. Air permeability, wicking ability and moisture permeability was tested to explore the water absorption property and moisture permeation property of the linen fabrics. The wear trials of the long sleeve shirt made of modified or unmodified linen fabrics were carried out in constant temperature and humidity chamber. The results show that modified linen fabric enhances the water absorption and moisture penetrability, and weakens the air permeability. Comparing with the long sleeve shirt made of unmodified linen fabric, it was clear that the thermal transfer performance of that made of modified fabric after sweating was improved. And the wet transfer property of the shirt made of modified fabric was better than that of the unmodified fabric, as well as the shirt made of refined fabric was better than that of the preliminary modified fabric. So the modified linen fabrics maintain a comfortable clothing microclimate.

Instrumentation for Measuring the Wet Frictional Property of Sanitary Pads

Women wear sanitary pad for whole day during their menstruation period. They have direct skin contact with it even for sleeping and exercising. The presence of sweat and menstrual blood increases the moisture level and the adhesion of liquid to textile causing sensorial discomfort. This study describes the design and uses of modified Textile Stickiness Measurement System (TSMS) which can characterize the frictional properties of sanitary pads under both dry and wet conditions. The uniqueness of this measurement system is that the wetness level of the pad is adjustable and the surface profile of the contacting object (i.e. Lorica®Soft) does simulate the condition of human skin. Also, it does not have restriction on the type of sanitary pad that can be tested. Among the 12 sanitary pads tested (disposable and reusable types), the frictional force for the disposable sanitary pads is lower than the reusable pads whilst the performance of disposable sanitary pads with nonwoven surface is lower than the one with perforated surface. These can attribute to their liquid transport property and surface feature. For those with better liquid transport property, less water will stay on skin surface and so the adhesion between skin and textiles is lower. For those with protruding fibers on its surface, it reduced the contact area and so the frictional force is lower.

Reactive grafting of 3-octanoylthio-1-propyltriethoxysilane in styrene butadiene rubber: Characterization and its effect on silica reinforced tire composites

A new grafting procedure was established in this present work, where propyltriethoxysilane moiety was successfully grafted in styrene butadiene rubber (SBR) using 3-Octanoylthio-1-propyltriethoxysilane and 2-mercaptobenzothiazole (MBT). Here MBT performed as a better free radical generator for the grafting of silane than peroxide, which is conventionally used. Successful grafting was proved by the Fourier Transform Infrared Spectroscopy (FTIR), where the peak at 1075 cm−1 was attributed to the presence of Si–O–C group. 9.5 wt percentage of grafting was found for SBR using MBT. On the contrary, with the use of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane (Trigonox 101), a high gel content and low amount of grafting (3%) was observed. Grafted structure was confirmed by 2 dimensional Proton Nuclear Magnetic Resonance spectroscopy. The properties of the grafted rubber are also reported here. The glass transition temperature increased and corresponding loss tangent decreased with grafting. In addition, rubber/silica composites were made where silane grafted SBR was used as a compatibilizer. Cure characteristics and other physical properties (Tensile strength, elongation at break, 300% modulus etc.) of the composites were examined. Better dispersion of silica in the grafted rubber matrix was confirmed by various techniques. Dynamic mechanical analysis showed improved rolling resistance and wet grip property indicating its great implications in tire and energy efficient applications.

Mechanical Properties of Natural Rubber Filled with Foundry Waste Derived Fillers.

The main aim of this study is to evaluate the possibility of applying foundry dust (FD) derived filler for the preparation of natural rubber (NR) based composites by characterizing the mechanical properties. The as-received FD was processed via a simple and low-cost procedure, including sieving, deironing and milling using a variety of industrial equipment. FD powders before and after silane coupling agent (Si 69) modification were used as fillers for NR. NR composites inserted with different content of modified and unmodified FD up to 50 phr were prepared via dry-mixing method. Then, comprehensive mechanical performances were performed on the corresponding vulcanizates. It was demonstrated that NR composite filled with 50 phr of modified FD exhibited optimized comprehensive mechanical performance. Tear strength and hardness is increased by 21.3% and 12.8% than pure NR, respectively. Tensile strength is reduced by 21% and elongation at break remained nearly unchanged. Additionally, the composite showed a large increment of 50.9% for its wet grip property, while exhibited an increment of only 11.9% for its rolling resistance in comparison with the composite containing 10 phr of FD. The findings of this study may provide a new application area for the large amounts of utilization of foundry waste with a high level of value being added.

Wedge Surface Plasmon Polariton Waveguides Based on Wet-Bulk Micromachining

In this paper, we propose and investigate the modal characteristics of wedge surface plasmon polariton (SPP) waveguides for guiding surface plasmon waves. The wedge SPP waveguides are composed of a silver layer deposited onto the surface of a wedge-shaped silicon dielectric waveguide. The wedge-shaped silicon dielectric waveguides are explored from the anisotropic wet etching property of single crystal silicon. The wedge SPP waveguides are embedded in a dielectric medium to form the metal–dielectric interface for guiding the surface plasmon waves. The propagation characteristics of the wedge SPP waveguides at the optical telecommunication wavelength of 1.55 μm are evaluated by a numerical simulation. The influence of the physical parameters such as the dimensions of the wedge SPP waveguide and the refractive index of the dielectric medium on the propagation of the surface plasmon wave is investigated. In addition, by comparing the propagation characteristics, we derive the wedge SPP waveguide with the optimal performance.