scholarly journals Study On The Effect of Tunicate Cellulose Nanocrystals in The Preparation of Sodium Alginate-Based Enteric Capsule

2021 ◽  
Author(s):  
Dezhong Xu ◽  
Yanan Cheng ◽  
Shuai Wu ◽  
Qiuxia Zou ◽  
Ajoy Kanti Mondal ◽  
...  
Keyword(s):  
Contact Angle ◽  
Aspect Ratio ◽  
Tensile Stress ◽  
Sodium Alginate ◽  
Control Sample ◽  
Maximum Tensile Stress ◽  
Water Contact ◽  
Elongation At Break ◽  
Enteric Capsule

Abstract In this work, the tunicate cellulose nanocrystal (tCNC) was extracted from tunicate by bleaching and acid hydrolysis. It was used as filler in the preparation of sodium alginate-based enteric capsule. The addition of tCNC with high aspect ratio (65) rendered the enteric capsule excellent physical properties. Compared with the control sample, when the addition of tCNC was 10% (wt), the water contact angle of the capsule was enhanced by 46.0%, the opacity was increased by 356.8%, the maximum tensile stress was increased by 142.6%, the modulus of elasticity was increased by 240.3%, and the elongation at break was increased by 133.8%. In the in vitro degradation experiments, the capsule hardly degraded in the gastric environment (pH 1.2), while in the intestinal environment (pH 6.8), the degradation became slower with the increase of tCNC content, which was consistent with the properties of enteric capsule. This research developed a new direction for the application of tCNC in the pharmaceutical material productions.

scholarly journals Durable Flame-Resistant and Ultra-Hydrophobic Aramid Fabrics via Plasma-Induced Graft Polymerization

Coatings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1257
Author(s):  
Eshraga A. A. Siddig ◽  
Yu Zhang ◽  
Baojing Yang ◽  
Tianshu Wang ◽  
Jianjun Shi ◽  
...  
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Graft Polymerization ◽  
Energy Dispersive Spectrometer ◽  
Control Sample ◽  
Flame Resistance ◽  
Water Contact ◽  
Washing Durability ◽  
Coated Fabrics ◽  
Aramid Fabrics

A durable flame-resistant and ultra-hydrophobic phosphorus–fluoride coating on aramid fabrics was achieved by plasma-induced graft polymerization. The aramid fabrics were activated and roughed through the low-pressure plasma firstly, which involves the sequential coating of a mixture of phosphorus–fluoride emulsion copolymer. When potentially exposed to flame or water, such a surface produces a dual effect in which it is intumescent and waterproof, successfully giving the coated fabrics flame-resistant ultra-hydrophobic bifunctional properties. Thus, adhesive coatings provide a convenient way to resolve the issue of washing durability of the coatings. The as-prepared fabrics last for 10 repeatable washing cycles without losing their flame resistance and superhydrophobicity, suggesting future applications as advanced multifunctional textiles. Compared to an untreated coating, its char length was less than 1 cm with no measurable after-flame or after-glow times, and its static water contact angle remained stable above 170°. Meanwhile, the control sample was unable to extinguish the fire with a damage length of 10.6 cm and a water contact angle of 100°. All the results indicate that plasma-reactive polar groups interact between phosphorus and fluorine elements, leading to an increased relative atom ratio P and F through Energy-Dispersive Spectrometer (EDS) spectra and XPS analysis, which inhibits the flammability and wettability.

Property Evaluation of Sodium Alginate/Chitosan Compound Dressings

2012 ◽  
Vol 627 ◽  
pp. 849-854 ◽  
Author(s):  
Ching Wen Lou ◽  
Chao Tsang Lu ◽  
Jin Jia Hu ◽  
Wei Jen Lin ◽  
Meng Chen Lin ◽  
...  
Keyword(s):  
Contact Angle ◽  
Weight Loss ◽  
Sodium Alginate ◽  
Water Contact Angle ◽  
Polymer Materials ◽  
Optimal Parameters ◽  
Water Contact ◽  
Optimum Parameters ◽  
Property Evaluation ◽  
Content Ratio

Polymer materials such as sodium alginate, chitosan, polylactic acid, and pectin, are commonly used as biomedical materials. This study combines sodium alginate (SA) and chitosan solutions to make the compound membranes. The compound membranes with optimal parameters are then combined with base fabrics, forming the compound dressings. SA and chitosan are mixed with various ratios, and then added with calcium chloride (CaCl2 (aq)), after which the mixture is thermally treated to form the SA/chitosan compound membranes. Moisture retention, swelling, weight loss, water contact angle, and water content ratio tests evaluate the resulting membranes, determining the optimum parameters. When the ratio of SA to chitosan is 7:3, the resulting membranes exhibit an optimal swelling. The weight loss of the membranes starts decreasing with the addition of CaCl2 (aq), indicating an increase in the structural stability of the compound membranes. Lastly, the water contact angle of all compound membranes is smaller than 90°, stating that they have a good hydrophilicity.

scholarly journals Synthesis and Characterization of Biodegradable Polyester/Polyether WPU As The Environmental Protection Coating

2021 ◽  
Author(s):  
Guangfeng Wu ◽  
Xin Song ◽  
ZhiHui Yang ◽  
Ying Chun Li ◽  
HuiXuan Zhang
Keyword(s):  
Thermal Stability ◽  
Contact Angle ◽  
Water Contact Angle ◽  
Degradation Rate ◽  
Soft Segment ◽  
Buffer Solution ◽  
Water Contact ◽  
Elongation At Break ◽  
Protection Coating

Abstract Polyester diol PCL and PBA, polyether diol PTMG and polycarbonate diol PCDL were used as components of WPU soft segment, respectively. Polyether PTMG-WPU has the worst hydrolytic property and the highest thermal stability. The maximum degradation rate temperature Tmax is 407.8°C, the water contact angle reaches 89.5°. Traditional polyester PCL-WPU shows the strongest hydrolysis performance, the smallest water contact angle, only 71.7°, the water absorption rate of 72 hours at room temperature is as high as 26.7%. However, the thermal stability of PCL-WPU is lower, the soft segment Tg is -52.3°C, and Tmax is only 333.7°C, but the mechanical propertie of which is the best, the tensile strength is 58.3 MPa, and the elongation at break reaches 857.9%. The most important thing is that the structure of polyester PCL-WPU is more easily destroyed by lipase and water molecules. The acidic products produced after hydrolysis will further promote the degradation of polyester. Therefore, compared with other WPUs, PCL -WPU has the best biodegradability and the most obvious degradation effect under the same conditions. The degradation rate of PTMG-WPU after 30 days of degradation in 0.6% lipase PBS buffer solution and soil was only 4.2% and 2.3%, while the highest degradation rate of traditional polyester PCL-WPU reached 41.7% and 32.0%, respectively. In addition, polycarbonate PCDL-WPU has the highest hardness, reaching 95.5 HD. But its other performances are lower than PCl-WPU.

Effects of Titanium Surface Wettability on Osteoblast Behavior In Vitro

2020 ◽  
Vol 985 ◽  
pp. 64-68
Author(s):  
Kenta Nisogi ◽  
Satoshi Okano ◽  
Sengo Kobayashi ◽  
Kensuke Kuroda ◽  
Takeaki Okamoto
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Titanium Surface ◽  
Pure Titanium ◽  
Hydrophobic Surface ◽  
Surface Wettability ◽  
In Vitro Assays ◽  
Water Contact ◽  
Heat Treated

Surface wettability is thought to influence the osteoconductivity of bone-substituting materials; however, the effects of surface wettability on osteoblast behavior are not well understood. In this study, we prepared both an as-polished pure titanium with a water contact angle (WCA) of 57° and heat-treated pure titanium with more hydrophobic surface and WCAs of 68°-98°. The effects of the surface wettability of pure titanium on osteoblast behaviors were evaluated by in vitro assays. Compared with the as-polished titanium, the proliferation rate of osteoblast increased on heat-treated titanium. This suggested that surface wettability affects osteoblast behaviors, meaning osteoconductivity is influenced by surface wettability.

scholarly journals Emulsion Electrospun Fiber Mats of PCL/PVA/Chitosan and Eugenol for Wound Dressing Applications

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Cláudia Mouro ◽  
Manuel Simões ◽  
Isabel C. Gouveia
Keyword(s):  
Contact Angle ◽  
Antibacterial Activity ◽  
Wound Dressing ◽  
Electrospun Fiber ◽  
Total Porosity ◽  
Dermal Fibroblasts ◽  
Wound Management ◽  
Water Contact ◽  
Fiber Mats

In recent years, the damaging effects of antimicrobial resistance relating to wound management and infections have driven the ongoing development of composite wound dressing mats containing natural compounds, such as plant extracts and their derivatives. The present research reports the fabrication of novel electrospun Polycaprolactone (PCL)/Polyvinyl Alcohol (PVA)/Chitosan (CS) fiber mats loaded with Eugenol (EUG), an essential oil, known for its therapeutic properties. The electrospun fiber mats were prepared via electrospinning from either water-in-oil (W/O) or oil-in-water (O/W) emulsions and characterized using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), total porosity measurements, and water contact angle. The in vitro EUG release profile and antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa were also evaluated. The obtained results proved that the EUG was loaded efficiently into electrospun PCL/PVA/CS fiber mats and the two W/O and O/W emulsions prepared from the PCL/PVA/CS (7 : 3 : 1) and PCL/PVA/CS (3 : 7 : 1) revealed porosity within the ideal range of 60–90%, even when EUG was loaded. The measured contact angle values showed that the O/W emulsion exhibited a more hydrophilic character and the wettability noticeably decreased after adding EUG in both emulsion blends. Furthermore, the electrospun PCL/PVA/CS fiber mats demonstrated a rapid release of EUG during the first 8 hours, which enhanced gradually afterward (up to 120 hours). Moreover, an efficient antibacterial activity against S. aureus (inhibition ratios of 92.43% and 83.08%) and P. aeruginosa (inhibition ratios of 94.68% and 87.85%) was displayed and the in vitro cytotoxic assay demonstrated that the normal human dermal fibroblasts (NHDF) remained viable for at least 7 days, after direct contact with the produced electrospun fiber mats. Therefore, such findings support the biocompatibility and suitability of using these EUG-loaded electrospun PCL/PVA/CS fiber mats as a new innovative wound dressing material with potential for preventing and treating microbial wound infections.

scholarly journals Physical Properties and In Vitro Biocompatible Evaluation of Silicone-Modified Polyurethane Nanofibers and Films

Nanomaterials ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 367 ◽  
Author(s):  
Chuan Yin ◽  
Sélène Rozet ◽  
Rino Okamoto ◽  
Mikihisa Kondo ◽  
Yasushi Tamada ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Cell Proliferation ◽  
Physical Properties ◽  
Water Retention ◽  
Embryonic Fibroblasts ◽  
Water Contact ◽  
Elongation At Break ◽  
In Vitro Biocompatibility ◽  
Short Period

In this study, the physical properties and the biocompatibility of electrospun silicone-modified polyurethane (PUSX) nanofibers were discussed and compared with PUSX films. To investigate the effects of different structures on the physical properties, tensile strength, elongation at break, Young’s modulus, water retention, water contact angle (WCA) and thermal conductivity measurements were performed. To prove the in vitro biocompatibility of the materials, cell adhesion, cell proliferation, and cytotoxicity were studied by NIH3T3 mouse embryonic fibroblasts cells following by lactate dehydrogenase (LDH) analysis. As a conclusion, the mechanical properties, water retention, and WCA were proven to be able to be controlled and improved by adjusting the structure of PUSX. A higher hydrophobicity and lower thermal conductivity were found in PUSX nanofibers compared with polyurethane (PU) nanofibers and films. An in vitro biocompatibility evaluation shows that the cell proliferation can be performed on both PUSX nanofibers and films. However, within a short period, cells prefer to attach and entangle on PUSX nanofibers rather than PUSX films. PUSX nanofibers were proven to be a nontoxic alternative for PU nano-membranes or films in the biomedical field, because of the controllable physical properties and the biocompatibility.

scholarly journals Simple method of fabrication of hydrophobic coatings for polyurethanes

2011 ◽  
Vol 9 (6) ◽  
pp. 1039-1045 ◽  
Author(s):  
Beata Butruk ◽  
Paulina Ziętek ◽  
Tomasz Ciach
Keyword(s):  
Contact Angle ◽  
High Efficiency ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Acoustic Microscopy ◽  
Water Contact ◽  
Simple Method ◽  
Hydrophobic Coatings ◽  
Grafting Reaction

AbstractThe aim of this study was to develop a method of manufacturing versatile hydrophobic coatings for polymers. Authors present a simple technique of polyurethane (PU) surface modification with covalently attached silicones (PDMS) or fluorocarbons (PFC). Diisocyanates were applied as linker molecules. The obtained coatings were characterized using spectroscopic analysis (FTIR), scanning acoustic microscopy (SAM) and water contact angle measurements. FTIR analysis revealed high efficiency of grafting reaction. The results of contact angle measurement indicated significant increase of hydrophobicity — from 66° (unmodified PU) to 113° (PU grafted with PDMS) and 118° (PU grafted with PFC). Acoustic microscopy analysis confirmed satisfactory homogeneity and smoothness of the fabricated layers. In vitro cell tests revealed non-adherent properties of the surfaces. Both, MTT assay and fluorescence staining confirmed non-cytotoxicity of the coatings, which makes them potential candidates for use in biomedical applications.

Physical and Mechanical Properties of Chitosan Films Incorporated with Florida Mandarin Oil

2014 ◽  
Vol 881-883 ◽  
pp. 1153-1156 ◽  
Author(s):  
Yun Bin Zhang ◽  
Jing Wen Wang ◽  
Ping Ping Jiang ◽  
Yue Xia Li ◽  
Xiao Yu Liu
Keyword(s):  
Mechanical Properties ◽  
Contact Angle ◽  
Water Contact Angle ◽  
Water Solubility ◽  
Composite Films ◽  
Physical And Mechanical Properties ◽  
Water Contact ◽  
Elongation At Break ◽  
Alkali Leaching ◽  
Chitosan Composite

Florida mandarin oil-chitosan composite films were prepared with chitosan (CS), Florida mandarin oil (FMO) by casting-evaporation-alkali leaching method. Influences of FMO to mechanical properties, water contact angle, water-solubility of films were evaluated. The results demonstrated that decrease of film tensile strength was caused by addition of FMO. When FMO content was 4%, elongation at break reached the maximum (2.81±0.01%). Water contact angle and solubility of film increased with increase of FMO content, maximums were 81.80±0.09° and 1.51±0.02 mg/100 g H2O, respectively.

scholarly journals EFFECTS OF STARCH-GLYCEROL CONCENTRATION RATIO ON MECHANICAL AND THERMAL PROPERTIES OF CASSAVA STARCH-BASED BIOPLASTICS

2019 ◽  
Vol 20 (4) ◽  
pp. 162
Author(s):  
Akbar Hanif Dawam Abdullah ◽  
Oceu Dwi Putri ◽  
Winda Windi Sugandi
Keyword(s):  
Contact Angle ◽  
Tensile Strength ◽  
Thermal Properties ◽  
Concentration Ratio ◽  
Surface Hydrophobicity ◽  
Cassava Starch ◽  
Mechanical And Thermal Properties ◽  
Glycerol Concentration ◽  
Water Contact ◽  
Elongation At Break

This study aimed to investigate the effects of different starch-glycerol concentration ratio on mechanical and thermal properties of cassava starch bioplastics. Bioplastics were prepared by mixing starch with glycerol at different starch-glycerol w/w ratio (2.5:1, 2.75:1, 3:1 and 3.5:1). Mechanical properties was evaluated by measuring tensile strength and elongation at break where thermal properties was assessed by thermogravimetric analysis to determine the glass transition temperature (Tg), melting temperature (Tm) and melting enthalpy (ΔHm) of bioplastics. Microstructure and chemical interactions in bioplastics were evaluated by SEM and FTIR. The surface hydrophobicity was determined by measuring the water contact angle. The increase of starch-glycerol concentration in bioplastics formed rough surface where the interaction of glycerol and starch molecules mainly occurred through hydrogen bonds. It also formed stronger and more rigid structure with the increase in tensile strength from 1.90 MPa to 2.47 MPa and the decrease in elongation at break from 8.55% to 5.92%. Furthermore, the increase of starch-glycerol concentration increased Tg from 37.5 ºC to 38.6 ºC, Tm from 96.3 ºC to 120.7 ºC and ΔHm from 100.4 J/g to 155 J/g. Moreover, surface contact angle of bioplastics was increased from 40.6º to 60.2º with the increase of starch-glycerol concentration ratio.

scholarly journals Cell Integration with Electrospun PMMA Nanofibers, Microfibers, Ribbons, and Films: A Microscopy Study

2019 ◽  
Vol 6 (2) ◽  
pp. 41 ◽  
Author(s):  
Daniel P. Ura ◽  
Joanna E. Karbowniczek ◽  
Piotr K. Szewczyk ◽  
Sara Metwally ◽  
Mateusz Kopyściański ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Fiber Diameter ◽  
3D Structure ◽  
Microscopy Study ◽  
Tissue Growth ◽  
Culture Study ◽  
Water Contact ◽  
Cell Culture Study

Tissue engineering requires properly selected geometry and surface properties of the scaffold, to promote in vitro tissue growth. In this study, we obtained three types of electrospun poly(methyl methacrylate) (PMMA) scaffolds—nanofibers, microfibers, and ribbons, as well as spin-coated films. Their morphology was imaged by scanning electron microscopy (SEM) and characterized by average surface roughness and water contact angle. PMMA films had a smooth surface with roughness, Ra below 0.3 µm and hydrophilic properties, whereas for the fibers and the ribbons, we observed increased hydrophobicity, with higher surface roughness and fiber diameter. For microfibers, we obtained the highest roughness of 7 µm, therefore, the contact angle was 140°. All PMMA samples were used for the in vitro cell culture study, to verify the cells integration with various designs of scaffolds. The detailed microscopy study revealed that higher surface roughness enhanced cells’ attachment and their filopodia length. The 3D structure of PMMA microfibers with an average fiber diameter above 3.5 µm, exhibited the most favorable geometry for cells’ ingrowth, whereas, for other structures we observed cells growth only on the surface. The study showed that electrospinning of various scaffolds geometry is able to control cells development that can be adjusted according to the tissue needs in the regeneration processes.

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