scholarly journals Functionalized branched EDOT-terthiophene copolymer films by electropolymerization and post-polymerization “click”-reactions

2015 ◽  
Vol 11 ◽  
pp. 335-347 ◽  
Author(s):  
Miriam Goll ◽  
Adrian Ruff ◽  
Erna Muks ◽  
Felix Goerigk ◽  
Beatrice Omiecienski ◽  
...  
Keyword(s):  
Energy Levels ◽  
Contact Angles ◽  
Redox Properties ◽  
Dipolar Cycloaddition ◽  
Surface Polarity ◽  
Water Contact ◽  
Click Reactions ◽  
Copolymer Films ◽  
Post Functionalization

The electrocopolymerization of 3,4-ethylenedioxythiophene (EDOT) with the branched thiophene building block 2,2′:3′,2″-terthiophene (3T) is presented as a versatile route to functional polymer films. Comparisons to blend systems of the respective homopolymers PEDOT and P3T by in situ spectroelectrochemistry and Raman spectroscopy prove the successful copolymer formation and the access to tailored redox properties and energy levels. The use of EDOT-N3 as co-monomer furthermore allows modifications of the films by polymer analogous reactions. Here, we exemplarily describe the post-functionalization with ionic moieties by 1,3-dipolar cycloaddition (“click”-chemistry) which allows to tune the surface polarity of the copolymer films from water contact angles of 140° down to 40°.

scholarly journals Hydrophobic Starch-Based Films Using Potato Washing Slurries and Spent Frying Oil

Foods ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2897
Author(s):  
Sílvia Petronilho ◽  
André Oliveira ◽  
M. Rosário Domingues ◽  
Fernando M. Nunes ◽  
Manuel A. Coimbra ◽  
...  
Keyword(s):  
Potato Starch ◽  
Contact Angles ◽  
Single Step ◽  
Frying Oil ◽  
Biodegradable Films ◽  
Water Contact ◽  
Alkaline Catalyst ◽  
Application Range ◽  
Structural Differences

Starch is a promising candidate for preparing biodegradable films with useful gas barriers and thermoplastic capabilities. However, these materials are hydrophilic and brittle, thus limiting their application range. To overcome these drawbacks, it has been hypothesized that starch can be hydrophobized and plasticized during the starch-based film production using a single-step approach and following transesterification principles. In this work, KOH powder and spent frying oil (SFO) were used as an alkaline catalyst and a source for triacylglycerides, respectively, to promote the modification of starch. Different ratios of SFO (w/w related to the dried starch weight) were tested. When compared to the neat films (without a catalyst and SFO), the incorporation of at least 15% SFO/KOH gave rise to transparent, hydrophobic (water contact angles of ca. 90°), stretchable (ca. 20×), elastic (ca. 5×), and water tolerant starch-based films, contrary to the films produced without the catalyst. ATR-FTIR and 1H NMR revealed structural differences among the produced films, suggesting that starch was modified with the SFO-derived fatty acids. Therefore, adding KOH during the potato starch/spent frying oil-based film’s production was determined to be a promising in situ strategy to develop starch-based materials with improved hydrophobicity and flexibility, while valorizing the potato chip industry’s byproducts.

scholarly journals In Situ Surface Modification of Paper-Based Relics with Atmospheric Pressure Plasma Treatment for Preservation Purposes

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 786
Author(s):  
Xu Yan ◽  
Guo-Sai Liu ◽  
Jing Yang ◽  
Yi Pu ◽  
Shuo Chen ◽  
...  
Keyword(s):  
Plasma Treatment ◽  
Atmospheric Pressure ◽  
Atmospheric Pressure Plasma ◽  
Good Method ◽  
Contact Angles ◽  
Water Penetration ◽  
Water Contact ◽  
Pressure Plasma ◽  
Static Water

Paper-based relics, which are an important part of cultural heritage worldwide, are at risk of imminent damage from various environmental sources. To protect them, the atmospheric pressure plasma polymerization of hexamethyldisiloxane (HMDSO) precursor has been explored on paper-based relics in situ. The macro and micro images taken during this process suggest that the in situ plasma treatment does not change the macro morphology and the micro structure of the treated paper-based relic samples. On the other hand, plasma treatment causes the polymerization of the HMDSO which then produces nanoparticles deposited onto the paper-based relics. These nanoparticles provide good waterproof properties with large static water contact angles and smaller rolling angles, which protect the paper-based relics from water penetration. Moreover, since the nanoparticles are deposited onto the fibers, waterproof fastness is ensured. Also, the examined mechanical properties of the treated and untreated paper-based relics indicate that the atmospheric pressure plasma treatment does not affect the strength of the paper very much. The results in this study show that atmospheric pressure plasma treatment with the use of HMDSO precursor is a good method to preserve paper-based relics.

Grafting Polypropylene under Ultrasonic in Water Suspension System

2015 ◽  
Vol 1095 ◽  
pp. 746-750
Author(s):  
Shuang Zhang ◽  
Bao Dong Zhu ◽  
Qing Ming Meng ◽  
Na Li ◽  
Jian Wang
Keyword(s):  
Contact Angles ◽  
Suspension System ◽  
Ultrasonic Frequency ◽  
Surface Polarity ◽  
Water Contact ◽  
Melt Flow Rate ◽  
Water Suspension ◽  
Swell Ratio ◽  
Grafting Ratio ◽  
Short Time

Polypropylene (PP) was grafted with styrene (ST), maleic anhydride (MAH) and butyl acrylate (BA) by free radical thermal initiation leading to (PP-g-PSMB) in water suspension system. The effects of ultrasonic frequency and time were investigated on PP grafting ratio in swelling stage. The structure of grafted product was analyzed by FTIR and melt flow rate (MFR), die swell ratio (Dr) and water contact angles of the grafted product were tested. The results show that the grafting ratio of PP can be improved in a short time by using ultrasonic significantly. The grafting ratio of PP increased with the increase of ultrasonic frequency. Ternary-monomer was grafted onto the PP chain branching in the form of long chain uniformly. The surface polarity of the grafted product was improved significantly.

The Study on the Synthesis of Polyfluoroacrylate

2013 ◽  
Vol 395-396 ◽  
pp. 351-354
Author(s):  
Qin Huan Yang
Keyword(s):  
Contact Angle ◽  
Particle Size ◽  
Polymer Film ◽  
Water Contact Angle ◽  
Film Surface ◽  
Contact Angles ◽  
Fluoride Content ◽  
Water Contact ◽  
Copolymer Films ◽  
High Fluoride

Cationic polyfluoroacrylate has been synthesized in the dual presence of cationic and non-ionic emulsifiers. Optimization studies indicated that the optimal proportions of cationic emulsifier 1631 and non-ionic emulsifiers FSA and AEO-9 were 1.75%, 1.25%, and 0.08%, respectively. Under these conditions, the conversion to the polymer was 92.5%, the particle size was 142 nm, and the water contact angle on a polymer film surface was 94.0°. With increasing dosage of hydrocarbon emulsifier, the water contact angles of copolymer films decreased dramatically. The magnitude of this decrease for a polymer with low fluoride content was greater than that for a polymer with high fluoride content. The fluorinated emulsifier FSA behaved similarly to the hydrocarbon emulsifier.

scholarly journals Facile Fabrication and Properties of Super-hydrophobic MgAl-LDH Films With Excellent Corrosion Resistance on AZ31 Magnesium Alloy

2021 ◽  
Vol 8 ◽  
Author(s):  
Xing Han ◽  
Jia Hu ◽  
Yong-Qin Wang ◽  
Tian-Bing Xiao ◽  
Wei Xia ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Corrosion Resistance ◽  
Magnesium Alloy ◽  
Electrochemical Impedance ◽  
Immersion Test ◽  
Contact Angles ◽  
Az31 Magnesium Alloy ◽  
Water Contact ◽  
Double Hydroxides

A super-hydrophobic anti-corrosion film was facilely prepared via in situ growth of layered double hydroxides (LDHs) on the etched AZ31 magnesium alloy and then modification by 1H, 1H, 2H, 2H-perfluorooctyltrimethoxysilane (PFOTMS) in this work. The morphology, structure, composition, surface roughness and water contact angles (WCA), and the anti-corrosion performance of the samples were investigated. The results revealed that the micro/nano hierarchical surface morphology of the films was composed of island structures obtained after chemical etching and MgAl-LDH nanowalls grown in situ. The best hydrophobicity (CA = 163°) was obtained on the MgAl-LDHs with the maximum surface roughness. Additionally, the potentiodynamic polarization, electrochemical impedance spectroscopy, and immersion test indicated that the super-hydrophobic LDH films provided better corrosion resistance to AZ31 magnesium alloy due to the double-protection derived from the LDHs and super-hydrophobic properties. Furthermore, the contact angle could be kept at above 140° after dipped in 3.5 wt% NaCl solution for 6 days.

scholarly journals The Effect of Hydroxyl on the Superhydrophobicity of Dodecyl Methacrylate (LMA) Coated Fabrics through Simple Dipping-Plasma Crosslinked Method

Coatings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1263
Author(s):  
Liyun Xu ◽  
Yu Zhang ◽  
Ying Guo ◽  
Ruiyun Zhang ◽  
Jianjun Shi ◽  
...  
Keyword(s):  
Thermoplastic Polyurethane ◽  
Hydrophobic Effect ◽  
Surface Hydrophobicity ◽  
Contact Angles ◽  
Binding Property ◽  
Interesting Phenomenon ◽  
Water Contact ◽  
Capacitively Coupled ◽  
Pet Fabric ◽  
Dodecyl Methacrylate

In order to obtain stable superhydrophobicity, suitable hydrophobic treatment agents should be selected according to different material properties. In this paper, cotton and poly(ethylene terephthalate) (PET) fabrics were respectively coated with dodecyl methacrylate (LMA) via argon combined capacitively coupled plasma (CCP), and the surface hydrophobicity and durability of the treated cotton and polyester fabrics are also discussed. An interesting phenomenon happened, whereby the LMA-coated cotton fabric (Cotton-g-LMA) had better water repelling and mechanical durability properties than LMA-coated PET fabric (PET-g-LMA), and LMA-coated hydroxyl-grafted PET fabrics (PET fabrics were successively coated with polyethylene glycol (PEG) and LMA, PET-g-PEG & LMA) had a similar performance to cotton fabrics. The water contact angles of Cotton-g-LMA, PET-g-LMA and PET-g-PEG & LMA were 156°, 153° and 155°, respectively, and after 45 washing cycles or 1000 rubbing cycles, the corresponding water contact angles decreased to 145°, 88°, 134° and 146°, 127° and 143°, respectively. Additionally, thermoplastic polyurethane (TPU) and polyamides-6 (PA6) fabrics all exhibited the same properties as the PET fabric. Therefore, the grafting of hydroxyl can improve the hydrophobic effect of LMA coating and the binding property between LMA and fabrics effectively, without changing the wearing comfort.

scholarly journals Polypropylene/Lignin/POSS Nanocomposites: Thermal and Wettability Properties, Application in Water Remediation

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3950
Author(s):  
Abeer Alassod ◽  
Syed Rashedul Islam ◽  
Mina Shahriari Khalaji ◽  
Rogers Tusiime ◽  
Wanzhen Huang ◽  
...  
Keyword(s):  
Organic Liquid ◽  
Contact Angles ◽  
Water Remediation ◽  
Scanning Calorimetry ◽  
Water Contact ◽  
Thermally Induced ◽  
Dsc Measurements ◽  
Infrared Measurement ◽  
Oligomeric Silsesquioxane ◽  
Tga And Dsc

Compositing is an interesting strategy that has always been employed to introduce or enhance desired functionalities in material systems. In this paper, sponges containing polypropylene, lignin, and octavinyl-polyhedral oligomeric silsesquioxane (OV-POSS) were successfully prepared via an easy and elegant strategy called thermally induced phase separation (TIPS). To fully explore the behaviour of different components of prepared sponges, properties were characterized by a thermogravimetric analyser (TGA), differential scanning calorimetry (DSC), Fourier transform infrared measurement (FTIR), and scanning electron microscopy (SEM). Furthermore, wettability properties toward an organic liquid and oil were investigated. The FTIR analysis confirmed the chemical modification of the components. TGA and DSC measurements revealed thermal stability was much better with an increase in OV-POSS content. OV-POSS modified sponges exhibited ultra-hydrophobicity and high oleophilicity with water contact angles of more than 125°. The SEM revealed that POSS molecules acted as a support for reduced surface roughness. Moreover, OV-POSS-based blend sponges showed higher sorption capacities compared with other blend sponges without OV-POSS. The new blend sponges demonstrated a potential for use as sorbent engineering materials in water remediation.

scholarly journals Physico-Chemical Characterization and Antimicrobial Properties of Hybrid Film Based on Saponite and Phloxine B

Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 325
Author(s):  
Nitin Chandra teja Dadi ◽  
Matúš Dohál ◽  
Veronika Medvecká ◽  
Juraj Bujdák ◽  
Kamila Koči ◽  
...  
Keyword(s):  
Hybrid Film ◽  
Antimicrobial Properties ◽  
Chemical Characterization ◽  
Layered Silicate ◽  
Contact Angles ◽  
Exchange Capacity ◽  
Resistant Bacteria ◽  
Hybrid Films ◽  
Water Contact ◽  
Physico Chemical

This research was aimed at the preparation of a hybrid film based on a layered silicate saponite (Sap) with the immobilized photosensitizer phloxine B (PhB). Sap was selected because of its high cation exchange capacity, ability to exfoliate into nanolayers, and to modify different surfaces. The X-ray diffraction of the films confirmed the intercalation of both the surfactant and PhB molecules in the Sap film. The photosensitizer retained its photoactivity in the hybrid films, as shown by fluorescence spectra measurements. The water contact angles and the measurement of surface free energy demonstrated the hydrophilic nature of the hybrid films. Antimicrobial effectiveness, assessed by the photodynamic inactivation on hybrid films, was tested against a standard strain and against methicillin-resistant bacteria of Staphylococcus aureus (MRSA). One group of samples was irradiated (green LED light; 2.5 h) and compared to nonirradiated ones. S. aureus strains manifested a reduction in growth from 1-log10 to over 3-log10 compared to the control samples with Sap only, and defects in S. aureus cells were proven by scanning electron microscopy. The results proved the optimal photo-physical properties and anti-MRSA potential of this newly designed hybrid system that reflects recent progress in the modification of surfaces for various medical applications.

Hypervalent-Iodine Mediated One-Pot Synthesis of Isoxazolines and Isoxazoles bearing Difluoromethyl Phosphonate Moiety

2021 ◽  
Author(s):  
Romana Pajkert ◽  
Henryk Koroniak ◽  
Pawel Kafarski ◽  
Gerd Volker Roeschenthaler
Keyword(s):  
Nitrile Oxide ◽  
Dipolar Cycloaddition ◽  
Hypervalent Iodine ◽  
One Pot ◽  
One Pot Synthesis

A one-pot, regioselective 1,3-dipolar cycloaddition of in situ generated (diethoxyphosphoryl)difluoromethyl nitrile oxide toward selected alkenes and alkynes is reported. This protocol enables facile access to 3,5-disubstituted isoxazolines and isoxazoles bearing...

Sign in / Sign up

Export Citation Format

Share Document