Original Fabric Research Articles

Attapulgite modified cotton fabric and its flame retardancy

Flame-retardant treatment for cotton fabric has been raising considerable interest. However, flame-retardant treatments in many studies have drawbacks, such as releasing toxic gases, high cost and weak bonding to the matrix. In this paper, attapulgite clay (ATP) was treated by ball-milling, activation and double-bond modification. Cotton fabric was grafted to achieve mercapto functionalization. Finally, the flame-retardant cotton fabric was prepared by grafting ATP onto the surface of the cotton fabric via thiol–ene click reaction. The resultant cotton fabric showed outstanding flame-retardant properties. Its burning rate, limiting oxygen index and maximum smoke density were 5.3 mm/s, 25.6% and 14.27%, respectively. Compared with the original cotton fabric, the flame-retardant properties of the obtained cotton fabric were significantly improved. It was attributed to the as-formed more stable oxide layer decomposed by ATP during burning. Furthermore, the as-prepared flame-retardant cotton fabric did not cause any health hazards. This work is favorable for promoting the development of halogen- and phosphorus-free flame-retardant cotton fabric.

Upcycling of waste textiles into regenerated cellulose fibres: impact of pretreatments

Due to several factors including textile waste accumulation and the use of environmentally harsh chemicals, the textile industry has become the second worst polluting industry worldwide. Therefore, significant effort is currently underway to find solutions to reduce this impact. In this study, coloured waste cotton fabrics were regenerated through a wet spinning process into new coloured fibres, hence recycling not only the fibre materials but also the colour. The impact of pretreatments on the colour retention and degree of polymerization of waste cotton-based fabrics was investigated in terms of the degree of polymerization of the waste cotton, the rheological properties of the spinning dope and the ability to maintain the original colour of the waste fabric. The spun fibres showed mechanical strength similar to commercial viscose fibre. The colour from the original fabric was retained under selected acid pretreatment conditions.

Superhydrophobic cotton fabric with excellent healability fabricated by the “grafting to” method using a diblock copolymer mist

A diblock copolymer, poly[(methyl methacrylate)-b-(trifluoroethyl methacrylate)] (PMMA-b-PTFMA), was synthesized via RAFT polymerization and was used to fabricate a healable superhydrophobic layer on cotton fabric surfaces via a mist treatment using an acetone solution. The PMMA block in the copolymer enabled covalent linkages with cellulose molecules on the fiber surface via transesterification reactions, while the PTFMA block acted as a functional part to endow the cotton fabric with new surface features. As a result, the modified cotton fabric displayed superhydrophobicity, with a water contact angle (WCA) above 160°. The resulting layer also exhibited excellent stability against laundering and abrasion. Even after 60 laundering cycles or 2000 abrasion cycles, the fabric still demonstrated a WCA higher than 140°. Moreover, this superhydrophobic property could be renewed using the common dry-cleaning agent, perchloroethylene (C2Cl4). This mist-modification approach was shown to have insignificant impacts on the desired cotton properties. The flexibility, water absorptivity, and vapor permeability of the original cotton fabric were largely preserved.

Effects of sample preparation on the microstructural signatures of faulting in clay-bearing fault gouge

Clay-rich fault gouge in the principal slip zones of faults stores abundant water within pores and between clay interlayers. During the preparation of thin-sections and rock chips for microstructural observations, fault-gouge samples are commonly air-dried at room temperature or in an oven. However, during the drying process, remnant liquid water between gouge grains produces an inter-particle adhesion force (liquid-bridge force), which rearranges the grain-to-grain structure, likely resulting in a disturbance of the original fabric. For this study, we prepared gouge samples from the Itozawa fault, northeastern Japan, using a t-butyl alcohol freeze-drying method that mitigates drying-induced fabric disturbance. We then compared the microstructure of our samples with those prepared using the conventional air-drying method. The freeze-dried samples preserve a smooth fault plane, clearly defined nanoparticles, and well-developed shear-sense indicators, including slickenlines and Riedel shear planes. In contrast, the air-dried samples underwent shrinkage during drying, which distorted the geometry of the fault plane. These air-dried samples lack nanoparticles and display only a weak shear fabric. We conclude that microstructural observations on samples prepared using the t-butyl alcohol freeze-drying method, compared with conventional air-drying, could preserve more evidence for the retrieval of fault information, including the kinematics, slip stability, and dynamic weakening mechanism of a fault.

Accessibility for Physically Challenged Persons in Heritage Buildings

Enforcement of amendment to the Uniform Building By-Law in Section 34A and Persons with Disability Act 2008 has elevated accessibility needs for physically challenged persons to mainstream development in Malaysia especially tourism industry. It is parallel to regional resolution and convention reiterating accessible tourism in the industry whilst achieve ‘Inclusive, barrier free and right based’ society. Accessibility has been further intensified within heritage buildings to benchmark high quality of tourism industry and importantly promotes social equality. In fact heritage tourism has been another gateway to elaborate fundamental accessibility needs of persons with disabilities in all aspects. Legislative framework has yet encapsulated both approaches comprehensively especially deficiency in provision of statutory requirements. There is lack of supportive guideline to address gaps between National Heritage Act and Persons with Disabilities Act. In this regards, current practice has shown professionals and consultants not well comprehend to weight balance between conservation principle and barrier free environment approach in restoring heritage buildings. However, the importance of accessibility needs is notably shown in the case studies to engage social inclusion in current practice. Access auditing reported the selected heritage sites including St. George Church, Leong San Tong Khoo Kongsi and Suffolk House have potential to include the accessibility needs without diminishing its heritage significance. As long access strategy and accessible mapping are identified during the initial stage to connect the core elements depending on its unique original fabric. Certainly never a fixed standard appending to current building regulations is applicable to all heritage sites. The research concluded barrier free environment approach is possible to reconcile with conservation principle within reasonable accommodation from case to cases basis.

Application of a novel plasma-based method of introducing maleic acid and pentaerythritol phosphate urea salt onto polyester fabrics for durable flame-retardant treatment

In this work, a novel anti-flame poly(ethylene terephthalate) (PET) fabric was successfully fabricated by plasma-based technology combined with pad-dry-cure treatment finishing. Low-temperature plasma can graft maleic acid (MA) onto a PET polymer backbone, which can activate the PET fiber and provide the opportunity of reaction with pentaerythritol phosphate urea salt (PEPAS) to achieve an excellent and durable anti-flame ability. Furthermore, the chemical reaction between PET-MA and PEPAS can form a complex and compact net structure that can effectively improve the anti-dripping property of PET. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and scanning electron microscopy analysis showed that MA and PEPAS were successfully introduced onto the surface of the PET fabric, and a compact protective carbon layer was formed during the combustion process due to the synergistic effect of phosphorus and nitrogen. The flame-retardant and anti-dripping properties were evaluated by thermogravimetric analysis, the limiting oxygen index (LOI) and a vertical burning test. The treated samples showed the maximum LOI value of 29.3, possessing excellent thermal stability and self-extinguishing ability and inhibiting melt-dripping ability. Moreover, tensile strength at break of the treated PET fabric was slightly greater than that of the original PET fabric, indicating that this type of treatment had little negative impact on the bulk of the PET fabric. After 20 laundering cycles, the LOI value of the treated sample still remained at 26.8, which indicated durability in the flame-retarding effect.

SHRIMP U–Pb phosphate dating shows metamorphism was synchronous with magmatism during the Paleoproterozoic Capricorn Orogeny

Unlike many Phanerozoic orogens, where the primary effects of orogenic events can be easily determined, Precambrian orogens are commonly characterised by repeated tectonothermal events making it challenging to decipher the geological history. The Capricorn Orogen is a complex Precambrian intraplate orogen located within the West Australian Craton that has been subjected to four separate reworking tectonic events between 1820 and 900 Ma. Although direct U–Pb ages for metamorphism have been obtained for the younger events, there is only limited geochronological data for the oldest event, the 1820–1770 Ma Capricorn Orogeny. This is primarily because of multiple episodes of deformation and metamorphism overprinting and obscuring the original tectonic fabrics and destroying metamorphic chronometers. In this study, we use in situ U–Pb monazite and xenotime geochronology, from a feldspathic metasandstone, a quartz–muscovite–chlorite–garnet pelitic schist, a quartz–muscovite–tourmaline schist and a garnet–biotite–plagioclase pelitic gneiss, to obtain the first direct age constraints for metamorphism during the Capricorn Orogeny in the northern Gascoyne Province. Metamorphism was synchronous with the 1820–1775 Ma magmatism in the northern part, and possibly in the southern part, of the Gascoyne Province. Furthermore, our results hint at a late stage hydrothermal fluid event at ca 1750–1730 Ma, post-dating the magmatism in the northern Gascoyne Province.

Weak B‐Type Olivine Fabric Induced by Fast Compaction of Crystal Mush in a Crustal Magma Reservoir

AbstractUnderstanding the deformation mechanisms of olivine has been considered as the crucial factor in tracing the dynamic processes from seismic anisotropy. Due to extensive overprinting of deformation and alteration, natural examples of original magmatic fabric of olivine are scarce. In this study we selected one wehrlite and three dunite samples from a deep borehole in the Poyi mafic‐ultramafic intrusion in the Tarim Craton. The fresh samples show adcumulate texture and plastic deformation of dry olivine (≤10 ppm H2O). Thermobarometer calculations yield crystallization conditions at 200–400 MPa and >1,124–1,275 °C. Olivine developed a B‐type fabric characterized by a concentration of [001] axes parallel to the interpreted lineation and that of [010] axes normal to the interpreted foliation. Activation of [001] and [100] dislocations is confirmed by microstructural observations. Simulation of gravity‐driven compaction process reveals extremely rapid compaction of kilometer‐scale crystal mush in the Poyi magmatic system. During the early compaction with high porosity, crystallographic habit of olivine may produce shape‐preferred orientation and the related B‐type fabric. In the final stage of compaction and crystallization, the initial shape‐preferred orientation was gradually overprinted, whereas the weak B‐type fabric has remained with dislocation creep and dislocation‐accommodated grain boundary sliding. Calculated seismic velocities of peridotite samples show low P and S wave anisotropies, with the fastest S wave polarization direction normal to the foliation. Hence, a mush‐dominated ultramafic intrusion exhibits weak seismic anisotropy, which has potential to better understand seismic anisotropy in the transcrustal magmatic systems.

The analysis of spatial and functional modifi cations of the palace in Krzesimów in Mełgiew commune aiming at adaptation of the building to the requirements of a social welfare home

The palace in Krzesimów was built in the classicist style at the beginning of 19th century. The building is the part of the palace-park complex entered into the register of monuments because of its historical, aesthetical and landscape values. From 1970s, it is the headquarters of a social welfare home. Over the years, this function enforced many changes in the functional layout of the building to adapt it to the needs of people with various types and levels of disability. Despite many minor renovations and modifi cations, the palace didn’t undergo complete overhaul, which would greatly improve the technical condition of the original fabric. This aim of article is to analyse introduced functional changes, which were supposed to facilitate the use of the building by the handicapped, and to consider what actions must be undertaken in order to improve its technical condition. The authors of the paper underline the need to start renovation works on the basis of the archive documentation, as well as conducted survey and research of its current technical condition.

Assessment of Structural and Conservation Practices on Vernacular Houses of Axum, Ethiopia

Historical buildings are one of the physical testimonies of early settlements and civilizations. The creativity of space, form and order of their houses, the techniques and technologies they have used, the methodologies of construction and building material selection is a mirror of the society’s knowledge and wisdom. But, those traditional houses that are heritages of Aksum are not documented yet. In order to document those traditional historical houses, identifying whether it is on its original fabric or transformed is a critical lesson. Therefore the main aim of this study is to investigate the physical condition of the selected vernacular houses and to assess their conservation practices. Using field visit, observations, structured and non-structured questionnaires and interviews, cross checking different data sources are used for qualitative data collections and the data has analyzed. From the selected case studies, most of them their physical structure is not at a good condition because of ownership issues and improper conservation practices due to need of modernization and urbanization like cement plastering, chemical paint, electricity installation and others that affect its original fabric. Responsible parties like governmental offices, universities, professional experts and stakeholders should document the vernacular houses and the conservation practices at different time and they should prepare conservation management plan or guidelines for the specific site to manage the conservation activities and practices. The responsible parties should work with the community in awareness creation to preserve those vernacular houses.

Shear-Thickening Fluid Using Oxygen-Plasma-Modified Multi-Walled Carbon Nanotubes to Improve the Quasi-Static Stab Resistance of Kevlar Fabrics.

The excellent mechanical property and light weight of protective materials are vital for practical application in body armor. In this study, O2-plasma-modified multi-walled carbon nanotubes (M-MWNTs) were introduced into shear-thickening fluid (STF)-impregnated Kevlar woven fabrics to increase the quasi-static stab resistance and decrease the composite weight. The rheological test showed that the addition of 0.06 wt. % M-MWNT caused a marked increase in the peak viscosity from 1563 to 3417 pa·s and a decrease in the critical shear rate from 14.68 s−1 to 2.53 s−1. The storage modulus (G′) and loss modulus (G″) showed a higher degree of abrupt increase with the increase of shear stress. The yarn pull-out test showed that the yarn friction of M-MWNT/STF/Kevlar fabrics was far superior to the original fabrics. Importantly, under similar areal density, the M-MWNT/STF/Kevlar fabrics could resist 1261.4 N quasi-static stab force and absorb 41.3 J energy, which were much higher than neat Kevlar fabrics. The results of this research indicated that quasi-static stab resistance was improved by M-MWNTs, which was attributed to the excellent shear-thickening effect and the high yarn friction. Therefore, M-MWNT/STF/Kevlar fabrics have a broad prospect in the fields of body protection.

Restoration of an Ottoman historical building in Istanbul

Preservation of historical buildings is an important issue to save our cultural heritage is both a record of life and history .In recent years the Turkish government starts urban transformation projects that include renewal and restoration of some historical buildings belongs to the Ottoman period. This paper present the details of a restoration project of a historical building in Istanbul. The selected restoration and strengthening technique aims to save the original architectural fabric of the building that has been changed among the last decades. The building is used as a chest diseases clinic in Istanbul University hospital. The building was built at the late-Ottoman period and composed of four building blocks. The structural system of the buildings is mainly unreinforced masonry URM walls. Seismic performance analysis results of the building before and after the proposed restoration scheme indicate that the resorted building is able to withstand future earthquakes safely.

Emplacement of the Triassic Pueblito Pluton, NW Colombia: Implications for the Evolution of the Western Margin of Pangea

We present the first structural geology focused study of a Triassic pluton in the Northern Andes, which provides new insights into the understanding of the tectonically complex northwestern corner of South America. Based on a combination of field structural data (377 stations) and a detailed magnetic susceptibility survey, 159 sites, we studied the structure of the Pueblito Pluton (PP), an original suprasubduction mafic cumulate structure emplaced in the northern part of the Arquia Terrane (western margin of Central Cordillera of Colombia). Even though the PP has resided along an active margin for over 230 million years ago, geochronology suggests no postcrystallization Ar-loss and, probably, no major reset of the original emplacement fabric. The PP magnetic fabric is dominatly parallel to the measured field foliation and formed under submagmatic to high-temperature conditions, at the final stages of cooling. The pluton internal contacts, mylonitic structures along the western margin, shape of the pluton, scalar parameters of the magnetic fabric, the directional field/magnetic data, and the geochronological data are compatible with a sinistral transpressional tectonic regime of emplacement by ca 233 Ma. This regime was regionally extended in the Arquia and Tahami Terranes (western margin of Pangea).

Surface Coating for Flame Retardancy and Pyrolysis Behavior of Polyester Fabric Based on Calcium Alginate Nanocomposites.

A polyester fabric, coated with calcium alginate and nano-calcium borate composites (CAB-PL), was fabricated by a post-cross-linking method, with remarkable improvement of flame retardancy and thermal stability, as compared with the original polyester fabric (PL). The mechanical properties of CAB-PL and PL were studied, and characterizations and tests including Fourier transform infrared spectrum (FTIR), scanning electron microscopy (SEM), limiting oxygen index (LOI), cone calorimetry (CONE) and thermogravimetric analysis (TGA) were employed to evaluate the flame retardancy and thermostability. The test results of CAB-PL showed excellent mechanical strength and anti-dripping properties. In comparison with PL, TGA results indicate that the presence of surface-coated composites produced more char residue and can effectively inhibit the heat transmission, and the LOI value of CAB-PL was improved from 25 to 33. Moreover, CONE results show that 88.65% reduction of total smoke release (TSR) values was induced by the presence of CAB. In addition, the possible pyrolysis mechanisms for CAB-PL have been proposed based on the results of pyrolysis-gas chromatography–mass spectrometry (Py-GC-MS) analysis. The combined results can provide useful information for understanding the flame retardant mechanisms of alginates as well. In summary, polyester fabric was upgraded by coating it with the calcium alginate/nano-calcium borate, thus achieving extraordinary flame retardancy and thermal stability for various applications within the textile industry.

Partial dissolution of carbonate rock grains during reactive CO2-saturated brine injection under reservoir conditions

One of the major concerns of carbon capture and storage (CCS) projects is the prediction of the long-term storage security of injected CO2. When injected underground in saline aquifers or depleted oil and gas fields, CO2 mixes with the resident brine to form carbonic acid. The carbonic acid can react with the host carbonate rock, and alter the rock structure and flow properties. In this study, we have used X-ray micro-tomography and focused ion beam scanning electron microscopy (FIB-SEM) techniques to investigate the dissolution behavior in wettability-altered carbonate rocks at the nm- to µm-scale, to investigate CO2 storage in depleted oil fields that have oil-wet or mixed-wet conditions. Our novel procedure of injecting oil after reactive transport has revealed previously unidentified (ghost) regions of partially-dissolved rock grains that were difficult to identify in X-ray tomographic images after dissolution from single fluid phase experiments. We show that these ghost regions have a significantly higher porosity and pore sizes that are an order of magnitude larger than that of unreacted grains. The average thickness of the ghost regions as well as the overall rock dissolution decreases with increasing distance from the injection point. During dissolution micro-porous rock retains much of its original fabric. This suggests that considering the solid part of these ghost regions as macro (bulk) pore space can result in the overestimation of porosity and permeability predicted from segmented X-ray tomographic images, or indeed from reactive transport models that assume a uniform, sharp reaction front at the grain surface.

Fabrication of composite membrane with adsorption property and its application to the removal of endocrine disrupting compounds during filtration process

A novel dual-layer composite membrane, which has integrated filtration and adsorption, was prepared from polyvinylidene fluoride (PVDF) membrane and functionalized polypropylene (PP) non-woven fabric (or PP-g-SA-HEA) support. Stearyl acrylate (SA) and hydroxyethyl acrylate (HEA) were first grafted onto the original PP non-woven fabric using ultraviolet (UV) irradiation graft polymerization. The resulting functionalized PP non-woven fabric was then coated with PVDF membrane via phase inversion. The characterization showed that the surface density and wettability of PP-g-SA-HEA varied with total amount and proportion of the grafted SA and HEA. At appropriate degree of grafting, the composite membrane formed a clear dual layers structure without any delamination and had enhanced mechanical properties. The dual-layer composite membrane was applied in filtration to remove low-concentration endocrine disrupting compounds (EDCs) from water. The results showed that the membrane was able to effectively remove bisphenol A (BPA) and other EDCs by adsorbing onto the PP-g-SA-HEA support layer. Compared to the single layer PVDF membrane, the filtration performance of the dual-layer composite membrane was not affected. In addition, the used membranes could be simply recovered by washing with mixed deionized water–ethanol solution.

A multidisciplinary study of the Lower Cretaceous marine to continental transition in the northern Austral-Magallanes basin and its geodynamic significance

Sedimentologic studies together with preliminary anisotropy of magnetic susceptibility (AMS) analysis were carried out in a very particular and intriguing Lower Cretaceous depocenter in the northern Austral-Magallanes basin, in order to elucidate its geodynamic setting. Aptian-Albian regressive sequences from the coastal Río Belgrano Formation and the fluvial conglomerates of Río Tarde Formation prograded into the regionally distributed marine sequence from Río Mayer Formation. This "early" progradation of continental environments is a characteristic of the northern sector of the basin, since marine conditions prevailed up to Campanian times towards the south. The tectonic context indicates a sudden passage from a marine to a deltaic and continental river system occurred during the uplift of the Northern Patagonian Andes and extra-Andean Patagonia. Our sedimentologic observations suggest a Barremian to Aptian regression, probably driven by the generalized uplift of surrounding blocks. AMS data indicates that a tectonic overprint of the original magnetic fabric was likely the product of E-W shortening applied soon after deposition, representing one of the earliest evidences of Andean deformation. Although the sedimentary setting was broadly placed in the retro-arc, our data helps to place the specific tectonic environment of the depocenter that is still little known and open to debate.

Relevance of ultrafine grains in the magnetic fabric of paleosols

The effects of pedogenic magnetic grains on the magnetic fabric of paleosols were investigated using samples from the Paks loess profile, Hungary. Rock magnetic experiments, electron probe microanalysis, and scanning electron microscopy revealed characteristic signatures of (post-)pedogenic influences on the original sedimentary fabric. No differences were observed between low- and high-frequency fabric, suggesting that the particle orientation distribution of superparamagnetic particles was isotropic or nearly isotropic. In some samples with low frequency dependence, the presence of superparamagnetic contributors was negligible compared to the coarser magnetic contributors. No inverse fabric was identified, indicating that stable single-domain magnetite had a negligible contribution to the fabric. Despite differences in the magnetic mineral content, the relative contributions of coarse and ultrafine grains appeared to be constant. Various methods of altering or preserving the sedimentary fabric during (post-)pedogenic processes were described. Some processes, such as the hydromorphic effect, weakened the anisotropy of the original fabric and strengthened the orientation of the grains. Meanwhile, other processes, such as post-burial, compaction of materials, and fragmentation, strengthened the foliation with increasing anisotropy. Processes that can fix the fabric and magnetic fabric of paleosols will allow us to use the fabric to determine the paleowind direction in the Pleistocene interglacial periods in future studies.

Strength, Stiffness and Radial Anisotropy of Compacted Silty Sand Under Suction-Controlled Axisymmetric Shearing

A thorough analysis of strength, stiffness, and stress-induced anisotropy of statically compacted silty sand is presented based on results from a comprehensive suction-controlled (drained) triaxial test program. Induced soil suction values, via either axis-translation or relative humidity techniques, ranged between 0.05 to 300 MPa, with net confining pressures varying from 100 to 300 kPa. A relatively simple model/equation for peak friction angle (ϕpeak), over the entire test suction and net confinement range, is presented. As expected, peak strength response to suction-controlled monotonic shearing is influenced by the level of suction and net confining pressure, as well as the amount of dilatancy experienced by the silty sand. The nonlinear nature of the variation of deviator stress at peak and critical state conditions, with degree of saturation, was fitted reasonably well via fourth order and second order polynomial equations, respectively. A thorough analysis and modeling of stress-dilatancy behavior is presented in a companion paper. Finally, the inherent-anisotropy observed in the original soil fabric, as well as the stress induced-anisotropy observed in the sheared samples, are discussed based on results from suction-controlled isotropic consolidation and axisymmetric shearing, respectively; including the effect of suction on the rate of degradation of stiffness (moduli) of compacted silty sand under monotonic shearing.

Preparation and properties of SiO2 aerogel and fabric composite based on polyurethane

ABSTRACTThe thermal insulation composite were prepared by blending aqueous polyurethane and modified SiO2 aerogel, and then coating to the surface of fabric. The influence of the content of SiO2 aerogel and polyurethane, crosslinking temperature and the particle size of SiO2 aerogel on thermal insulation rate of the composite fabric were detail analysis, the heat insulation, breathable, IR, SEM surface morphology of the composite fabric were evaluated. The thermal insulation rate of the SiO2 aerogel composite fabric is 28.97%, which is twice that of the original fabric. SiO2 aerogel composite fabric will have a wide range of application in the thermal insulation clothing, curtains, shoe materials, industrial equipment and building insulation, etc.