Improvement of bacterial cellulose nonwoven fabrics by physical entrapment of lauryl gallate oligomers

2019 ◽  
Vol 90 (2) ◽  
pp. 166-178 ◽  
Author(s):  
Ji Eun Song ◽  
Artur Cavaco-Paulo ◽  
Carla Silva ◽  
Hye Rim Kim
Keyword(s):  
Contact Angle ◽  
Tensile Strength ◽  
Bacterial Cellulose ◽  
Water Contact Angle ◽  
Dimensional Stability ◽  
Nonwoven Fabric ◽  
Water Contact ◽  
Nonwoven Fabrics ◽  
Physical Entrapment ◽  
Lauryl Gallate

The present study aimed to improve the properties of bacterial cellulose nonwoven fabrics by physical entrapment of lauryl gallate oligomers. The lauryl gallate oligomerization process was conducted by laccase-mediated oligomerization. Lauryl gallate was chemically confirmed by matrix-assisted laser desorption/ionization with time-of-flight analyses. The oligomerization conditions were controlled considering the surface properties (water contact angle, surface energy, and water absorption time) of bacterial cellulose nonwoven fabrics. The controlled oligomerization conditions were 160 U/mL of laccase and 20 mM lauryl gallate. After bacterial cellulose was treated by the physical entrapment of lauryl gallate oligomers, X-ray photoelectron spectroscopy analysis showed that the N1 atomic composition (%) of bacterial cellulose increased from 0.78% to 4.32%. This indicates that the lauryl gallate oligomer molecules were introduced into the bacterial cellulose nanofiber structure. In addition, the water contact angle was measured after washing the bacterial cellulose nonwoven fabric treated by the physical entrapment of lauryl gallate oligomers for 180 minutes, and it was found to maintain a water contact angle of 88°. The durability of bacterial cellulose nonwoven fabric treated by the physical entrapment of lauryl gallate oligomers was confirmed by measuring the tensile strength after wetting and dimensional stability. As a result, the tensile strength after wetting was about five times higher and the dimensional stability was three times higher than that of untreated bacterial cellulose nonwoven fabric.

Formation and characterization of superhydrophobic and alcohol-repellent nonwovens via electrohydrodynamic atomization (electrospraying)

2016 ◽  
Vol 47 (1) ◽  
pp. 125-146 ◽  
Author(s):  
Mehmet Dasdemir ◽  
Hatice Ibili
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Maximum Level ◽  
Solution Concentration ◽  
Water Mixture ◽  
Water Contact ◽  
Nonwoven Fabrics ◽  
Alcohol Water ◽  
Electrohydrodynamic Atomization ◽  
Coated Fabrics

This study focuses on the development of superhydrophobic and alcohol-repellent medical nonwoven fabrics via electrohydrodynamic atomization (electrospraying). It also compares the effectiveness of electrospraying with conventional pad-dry-cure finishing application. A commercial fluorochemical finishing agent was used to prepare fluorochemical solutions at varying concentrations (0.9–9 wt%). Electrospraying characteristics of these solutions were determined with characterizing their solution properties such as viscosity, conductivity and surface tension. After the successful applications of fluorochemical solutions on nonwoven fabrics via padding and electrospraying, wet pick-up ratios and weight gains of these fabrics were calculated. Also, water and alcohol repellencies of the coated fabrics were characterized with water contact angle and alcohol contact angle measurements. According to our findings, electrospraying application yielded less chemical consumption and higher water contact angle and alcohol contact angle results than padding. Increasing solution concentration and application time for electrospraying enhanced water contact angle values, which reached a maximum level (up to 156°) and afterwards remained almost constant depending on these variables. Thus, their limits to achieve superhydrophobic surfaces were able to be determined. Electrosprayed nonwovens were also shown to be alcohol-repellent against alcohol/water mixture of 70/30 (v/v%) whereas that was 30/70 (v/v%) for padded nonwovens. The investigation of the electrosprayed surfaces revealed a very less coating on the uppermost side of surface fibres which mostly led to the enhanced water and alcohol repellencies. One of the other important outcomes of this study is that there was no significant change on the comfort properties of nonwoven fabrics after the electrospraying application.

scholarly journals WATER REPELLENT BREATHABLE PET/WOOL FABRIC VIA PLASMA POLYMERISATION TECHNOLOGY

2021 ◽  
Vol 2021 ◽  
pp. 74-80
Author(s):  
A. Haji ◽  
M. Khajeh Mehrizi ◽  
M. Ali Tavanai ◽  
M. Gohari
Keyword(s):  
Contact Angle ◽  
Tensile Strength ◽  
Water Contact Angle ◽  
Air Permeability ◽  
Water Repellent ◽  
Wool Fabric ◽  
Water Contact ◽  
Hydrophobic Polymers ◽  
Treated Sample ◽  
Bending Length

Water-repellent textiles are usually prepared by application of hydrophobic polymers such as fluorocarbons on fabrics using padding or spraying methods followed by drying and curing steps. These procedures impart hydrophobicity to the fabric, but harm the physical and handle properties of the fabric. In this study, low-pressure plasma was employed for the polymerization of 1H,1H,2H,2H-Perfluorooctyl acrylate on PET/Wool fabric for obtaining water-repellent properties with minimum effect on other desirable properties. To compare the results with the conventional industrial processes, a sample was treated with a commercial water-repellent agent using pad-dry-cure method. The water contact angle, bending length, tensile strength, air permeability, and surface morphology of the samples were compared. The plasma-treated sample showed similar water contact angle and higher fastness properties compared with the sample prepared by the conventional method. The tensile strength of the samples was similar, while the air permeability of the plasmatreated sample was higher and the coating was more uniform compared with the sample prepared by the paddry- cure method.

Development of a superhydrophobic cellulose fabric via enzyme treatment and surface hydrophobization

2020 ◽  
Vol 91 (1-2) ◽  
pp. 40-50
Author(s):  
Md Ashikur Rahman ◽  
Changsang Yun ◽  
Chung Hee Park
Keyword(s):  
Contact Angle ◽  
Weight Loss ◽  
Tensile Strength ◽  
Enzymatic Hydrolysis ◽  
Water Contact Angle ◽  
Enzyme Concentration ◽  
Water Contact ◽  
Nano Scale ◽  
Cellulose Fabric ◽  
Scale Roughness

Enzymatic hydrolysis is a common finishing method for cellulosic materials, to improve fabric softness, appearance, and surface properties. However, its potential to trigger superhydrophobicity has not been studied in depth. In this study, a superhydrophobic cellulose fabric was fabricated in two steps. Micro-/nano-hierarchical roughness on the fabric surface was achieved by cellulase from Aspergillus niger, through enzymatic hydrolysis. Subsequently, hydrophobization was carried out by a dip coating method, using polydimethylsiloxane (PDMS). Enzyme concentration and treatment temperature were varied to find the values that provided the greatest superhydrophobicity. As enzyme concentration and temperature increased, the nano-scale roughness increased, along with weight reduction. The degree of crystallinity and reduction in tensile strength were also increased with weight loss via enzyme hydrolysis. As air pockets were formed by micro-/nano-structures on the fiber surface, the water contact angle increased and the shedding angle tended to decrease. The sample treated with 5 g/l enzyme at 60 ℃ for 60 min and coated with PDMS 1 wt.% coating solution had the greatest superhydrophobicity, with a water contact angle of 162° and a shedding angle of 7.0°. The weight loss and reduction in tensile strength of the developed superhydrophobic fabrics were 2.9% and 39.0%, respectively. This approach reduces the necessity for an additional process to introduce nano-scale roughness, and it has the potential to produce superhydrophobic cellulosic biomass for outdoor clothing.

Manufacturing Technique and Property Evaluations of PET/Gelatin Composite Tubular Braids

2014 ◽  
Vol 910 ◽  
pp. 157-160 ◽  
Author(s):  
Ching Wen Lou ◽  
Po Ching Lu ◽  
Jin Jia Hu ◽  
Jia Horng Lin
Keyword(s):  
Contact Angle ◽  
Tensile Strength ◽  
Physical Properties ◽  
Water Contact Angle ◽  
Physical Property ◽  
Gelatin Solution ◽  
Water Contact ◽  
Manufacturing Technique ◽  
Pet Fibers

This study examine the influence of gelatain with different concentrations on the physical property of the PET/Gelatin composite tubular braids. PET fibers are braided into tubular braids on a braider, and then immersed in gelatin solution with various concentrations to form PET/Gelatin composite tubular braids. The tensile strength and water contact angle of the braids are then tested to determine the their physical properties. The experiment results show that an increasing concentration of gelatin does not result in a significant varation in tensile strength, but a decreased displacement only.

Preparation of Carbonated Apatite Membrane as Metronidazole Delivery System for Periodontal Application

2016 ◽  
Vol 696 ◽  
pp. 250-258 ◽  
Author(s):  
Retno Ardhani ◽  
Setyaningsih ◽  
Osa Amila Hafiyyah ◽  
Ika Dewi Ana
Keyword(s):  
Contact Angle ◽  
Tensile Strength ◽  
Water Content ◽  
Water Contact Angle ◽  
Delivery System ◽  
Carbonate Apatite ◽  
Loading Capacity ◽  
Water Contact ◽  
Carbonated Apatite ◽  
Study Results

Introduction. Long term infection on periodontal tissue, mainly caused by anaerobic microbial, is not only related with tooth loss which lead to functional and esthetical impairment but also with increasing infection risk on other vital organs such as heart. Metronidazole is drug of choice for anaerobic bacterial infection. In this research, Metronidazole delivery system from carbonated apatite-based material was designed to increase the antibiotic therapeutic potential on local application as well as to promote tooth-supporting bone healing as a thin membrane to be applied on narrow periodontal tissue.Experimental. Metronidazole delivery system was prepared using different carbonate apatite composition on gelatin hydrogel system which was freeze-dried then polymerized by thermal treatment. Total 6 gelatin-carbonated apatite compositions were prepared: 10:0, 9:1, 8:2, 7:3, 6:4 and 5:5.The membranes were characterized by Fourier Transform Infrared (FTIR) spectroscopy, X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). Water-content, air-water contact angle, tensile strength, Metronidazole-loading capacity, degradation profile and Metronidazole-release profile were studied to describe each composition potential as Metronidazole delivery system.Results and Discussion. Study on FTIR spectra and XRD confirmed preparation methods as standard procedures to prepare membrane formed delivery system-containing carbonate apatite. Descriptively from SEM, the film surface porosity was elevated by the increase of carbonate apatite composition. Tensile strength decreased was found by the increase of carbonate apatite composition. Water content, air-water contact angle, Metronidazole-loading capacity was not different significantly (P>0.05). Profile of degradation and Metronidazole-release from the membranes was different between compositions.Conclusions. This study results were essential to support next research on antibiotic potential using different anaerobic bacteria culture as well as bone regeneration potential on periodontal infection in vivo.

Property Evaluation of Polylactic Acid Multilayer Braids Used as Bone Scaffolds

2012 ◽  
Vol 627 ◽  
pp. 844-848
Author(s):  
Jia Horng Lin ◽  
Hsiu Ying Chung ◽  
Shih Peng Wen ◽  
Wen Cheng Chen ◽  
Yueh Sheng Chen ◽  
...  
Keyword(s):  
Contact Angle ◽  
Tensile Strength ◽  
Optimal Condition ◽  
Polylactic Acid ◽  
Water Contact Angle ◽  
Tissue Scaffolds ◽  
Water Contact ◽  
Bone Scaffolds ◽  
Property Evaluation ◽  
Plied Yarn

Polylactic acid (PLA), which is biodegradable, is largely used as biomaterial such as bone scaffolds. This study twists PLA filaments into PLA plied yarn, during which twist per inch (TPI) varies as 9, 10, 11, 12, and 13. Tensile strength and elongation of the resulting plied yarn are then evaluated. The optimal TPI is 10, which results from an optimal tensile strength of 3.3 g/den and elongation of 42 %. The optimal plied yarn is made into PLA braids on a 16-spindle braiding machine, with a ratio of take-up gear to braid gear of 60:60, 70:60, 80:60, 90:60, or 100:60. The braids with various gear ratios are then made into multilayer braids with a diameter of 4 mm. The resulting multilayer braids are evaluated for surface observation, porosity and water contact angle. The optimal porosity is 55-65% and the optimal water contact angle is below 30°. This optimal condition indicates that the multilayer braid exhibit good hydrophilicity and a good candidate for bone tissue scaffolds.

Long-Term Stable Metal Organic Framework (MOF) Based Mixed Matrix Membranes for Ultrafiltration

2020 ◽  
Author(s):  
Muayad Al-shaeli ◽  
Stefan J. D. Smith ◽  
Shanxue Jiang ◽  
Huanting Wang ◽  
Kaisong Zhang ◽  
...  
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Mixed Matrix Membranes ◽  
Recovery Ratio ◽  
Mixed Matrix ◽  
Water Contact ◽  
Membrane Performance ◽  
Metal Organic ◽  
Matrix Membranes

<p>In this study, novel <a>mixed matrix polyethersulfone (PES) membranes</a> were synthesized by using two different kinds of metal organic frameworks (MOFs), namely UiO-66 and UiO-66-NH<sub>2</sub>. The composite membranes were characterised by SEM, EDX, FTIR, PXRD, water contact angle, porosity, pore size, etc. Membrane performance was investigated by water permeation flux, flux recovery ratio, fouling resistance and anti-fouling performance. The stability test was also conducted for the prepared mixed matrix membranes. A higher reduction in the water contact angle was observed after adding both MOFs to the PES and sulfonated PES membranes compared to pristine PES membranes. An enhancement in membrane performance was observed by embedding the MOF into PES membrane matrix, which may be attributed to the super-hydrophilic porous structure of UiO-66-NH<sub>2</sub> nanoparticles and hydrophilic structure of UiO-66 nanoparticles that could accelerate the exchange rate between solvent and non-solvent during the phase inversion process. By adding the MOFs into PES matrix, the flux recovery ratio was increased greatly (more than 99% for most mixed matrix membranes). The mixed matrix membranes showed higher resistance to protein adsorption compared to pristine PES membranes. After immersing the membranes in water for 3 months, 6 months and 12 months, both MOFs were stable and retained their structure. This study indicates that UiO-66 and UiO-66-NH<sub>2</sub> are great candidates for designing long-term stable mixed matrix membranes with higher anti-fouling performance.</p>

scholarly journals Surface modification of PMMA polymer and its composites with PC61BM fullerene derivative using an atmospheric pressure microwave argon plasma sheet

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Andrzej Sikora ◽  
Dariusz Czylkowski ◽  
Bartosz Hrycak ◽  
Magdalena Moczała-Dusanowska ◽  
Marcin Łapiński ◽  
...  
Keyword(s):  
Contact Angle ◽  
Surface Modification ◽  
Chemical Composition ◽  
Water Contact Angle ◽  
Plasma Sheet ◽  
Atmospheric Pressure ◽  
Argon Plasma ◽  
Fullerene Derivative ◽  
Water Contact ◽  
Pmma Polymer

AbstractThis paper presents the results of experimental investigations of the plasma surface modification of a poly(methyl methacrylate) (PMMA) polymer and PMMA composites with a [6,6]-phenyl-C61-butyric acid methyl ester fullerene derivative (PC61BM). An atmospheric pressure microwave (2.45 GHz) argon plasma sheet was used. The experimental parameters were: an argon (Ar) flow rate (up to 20 NL/min), microwave power (up to 530 W), number of plasma scans (up to 3) and, the kind of treated material. In order to assess the plasma effect, the possible changes in the wettability, roughness, chemical composition, and mechanical properties of the plasma-treated samples’ surfaces were evaluated by water contact angle goniometry (WCA), atomic force microscopy (AFM), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The best result concerning the water contact angle reduction was from 83° to 29.7° for the PMMA material. The ageing studies of the PMMA plasma-modified surface showed long term (100 h) improved wettability. As a result of plasma treating, changes in the samples surface roughness parameters were observed, however their dependence on the number of plasma scans is irregular. The ATR-FTIR spectra of the PMMA plasma-treated surfaces showed only slight changes in comparison with the spectra of an untreated sample. The more significant differences were demonstrated by XPS measurements indicating the surface chemical composition changes after plasma treatment and revealing the oxygen to carbon ratio increase from 0.1 to 0.4.

Sign in / Sign up

Export Citation Format

Share Document