Efficient approach to produce functional polypropylene via solvent assisted solid-phase free radical grafting of multi-monomers

AbstractHerein an efficient approach to produce functional polypropylene via solvent assisted solid-phase grafting process is reported, in which acrylic acid, methyl methacrylate and maleic anhydride are used as multi-monomers, 2,2′-azobis(2-methylpropionitrile) as initiator and ether as swelling solvent and carrier. The effects of various factors such as the swelling solvent species and dosage, swelling time and temperature, monomer and initiator concentrations, reaction time and temperature, nitrogen flow rate and the stirring speed on the grafting percentage and grafting efficiency were investigated. To verify the polar species was grafted onto polypropylene, the resulted polymers were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction analysis, water contact angle measurement, tensile strength and melt flow rate measurement. All the results showed that using the ether assisted solid-phase free radical grafting process is an efficient and versatile approach to produce functional polypropylene.

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Supercritical carbon dioxide-assisted solid-phase free radical grafting of butyl acrylate onto PP

e-Polymers ◽

10.1515/epoly.2009.9.1.1156 ◽

2009 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Wang Jian ◽

Wang Deng-Fei ◽

Du Wei ◽

Zou En-Guang ◽

Dong Qun

Keyword(s):

Free Radical ◽

Butyl Acrylate ◽

Solid Phase ◽

Particle Diameter ◽

Mechanical Analysis ◽

Gravimetric Analysis ◽

Experimental Conditions ◽

Water Contact ◽

Melt Flow Rate ◽

Grafting Reaction

AbstractFree radical grafting copolymerization of butyl acrylate (BA) onto polypropylene (PP) matrix was investigated using supercritical CO2 as a swelling agent and carrier solvent. The monomer BA and initiator AIBN were first dissolved in supercritical CO2, and then these small molecules were diffused into the grafting zones of PP matrix. As grafting reaction temperature (about 80 °C) was far below the melting point, PP was modified in the solid phase. The effects of different experimental conditions such as soaking time and temperature, supercritical CO2 pressure; monomer and initiator concentration; PP particle diameter; solid phase grafting reaction time and temperature on grafting percentage were studied. Fourier transform infrared spectroscopy (FTIR) results and gel content experiment prove that the monomers were indeed grafted onto PP chains. Scanning electron microscope (SEM) analysis of the grafted sample indicates that the grafting branches PBA were homogeneously distributed onto the surfaces and micropores of PP particles. Thermal gravimetric analysis (TGA) results show that the grafted samples had a higher onset thermal degradation temperature and a lower weight loss at a particular temperature than pure PP. The water contact angle of PP-g-BA decreased from 98° to 72°, indicating the polarity and hydrophilicity of PP were improved effectively. The melt flow rate (MFR) and mechanical analysis results show that the grafting sample remained its versatile physical properties though introducing the grafting BA branch chain. This is prominent when it was compared with normal solid grafting product.

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Fabrication and Characterization of Carboxymethyl Starch/Poly(l-Lactide) Acid/β-Tricalcium Phosphate Composite Nanofibers via Electrospinning

Polymers ◽

10.3390/polym11091468 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1468 ◽

Cited By ~ 4

Author(s):

Mohd Reusmaazran Yusof ◽

Roslinda Shamsudin ◽

Sarani Zakaria ◽

Muhammad Azmi Abdul Hamid ◽

Fatma Yalcinkaya ◽

...

Keyword(s):

Tricalcium Phosphate ◽

Composite Nanofibers ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Inorganic Materials ◽

X Ray Diffraction ◽

Mixed Composition ◽

Water Contact ◽

Carboxymethyl Starch ◽

Inorganic Mineral

A natural polymer of carboxymethyl starch (CMS) was used in combination with the inorganic mineral of β-Tricalcium Phosphate (β-TCP) and Poly l-lactide (PLLA) to prepare composite nanofibers with the potential to be used as a biomedical membrane. β-TCP contents varied in the range of 0.25% to 1% in the composition of PLLA and CMS. A mixed composition of these organic and inorganic materials was electro-spun to produce composite nanofibers. Morphological investigation indicated that smooth and uniform nanofibers could be produced via this technique. The average of the nanofiber diameters was slightly increased from 190 to 265 nm with the β-TCP content but some agglomeration of particles began to impede in the fiber at a higher content of β-TCP. It was observed that the fibers were damaged at a higher content of β-TCP nanoparticles. With the presence of higher β-TCP, the wettability of the PLLA was also improved, as indicated by the water contact angle measurement from 127.3° to 118°. The crystallization in the composite decreased, as shown in the changes in glass transition (Tg) and melting temperature (Tm) by differential scanning calorimeter (DSC) and X-ray diffraction analysis. Increases in β-TCP contributed to weaker mechanical strength, from 8.5 to 5.7 MPa, due to imperfect fiber structure.

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Superhydrophobic functionalized cellulosic paper by copper hydroxide nanorods for oils purification

Scientific Reports ◽

10.1038/s41598-021-95784-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ahmed S. Belal ◽

Jehan El Nady ◽

Azza Shokry ◽

Shaker Ebrahim ◽

Moataz Soliman ◽

...

Keyword(s):

Contact Angle ◽

Filter Paper ◽

Separation Efficiency ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Absorption Capacity ◽

Morphological Properties ◽

Copper Hydroxide ◽

Immersion Method ◽

Water Contact

AbstractOily water contamination has been sighted as one of the most global environmental pollution. Herein, copper hydroxide nanorods layer was constructed onto cellulosic filter paper surface cured with polydopamine, Ag nanoparticles, and Cu NPs through immersion method. This work has been aimed to produce a superhydrophobic and superoleophilic cellulosic filter paper. The structure, crystalline, and morphological properties of these modified cellulosic filter paper were investigated. Scanning electron microscope images confirmed that the modified surface was rougher compared with the pristine surface. The contact angle measurement confirmed the hydrophobic nature of these modified surfaces with a water contact angle of 169.7°. The absorption capacity was 8.2 g/g for diesel oil and the separation efficiency was higher than 99%. It was noted that the flux in the case of low viscosity solvent as n-hexane was 9663.5 Lm−2 h−1, while for the viscous oil as diesel was 1452.7 Lm−2 h−1.

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Plasma Pre-Treatment of Polyethylene Terephthalate Substrate Influence on the Properties of ZnO Thin Film

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.895.41 ◽

2014 ◽

Vol 895 ◽

pp. 41-44

Author(s):

Seiw Yen Tho ◽

Kamarulazizi Ibrahim

Keyword(s):

Thin Film ◽

Thin Films ◽

Polyethylene Terephthalate ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Zno Thin Films ◽

Zno Thin Film ◽

Water Contact ◽

Pre Treatment ◽

Pet Substrate

In this work, the influences of plasma pre-treatment on polyethylene terephthalate (PET) substrate to the properties of ZnO thin film have been carried out. ZnO thin films were successfully grown on PET substrate by spin coating method. In order to study the effects of plasma pre-treatment, a comparison of treated and untreated condition was employed. Water contact angle measurement had been carried out for PET wettability study prior to ZnO thin film coating. Morphology study of ZnO thin film was performed by scanning probe microscope (SPM). Besides, optical study of the ZnO thin film was done by using UV-vis spectrophotometer. All the measured results show that plasma pre-treatment of PET substrate plays an important role in enhancing the wettability of PET and optical properties of the ZnO thin films. In conclusion, pre-treatment of PET surface is essential to produce higher quality ZnO thin film on this particular substrate in which would pave the way for the integration of future devices.

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Preparation of TiO2–SiO2 Hybrid Nanosols Coated Flame-Retardant Polyester Fabric Possessing Dual Contradictory Characteristics of Superhydrophobicity and Self Cleaning Ability

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17166 ◽

2020 ◽

Vol 20 (3) ◽

pp. 1780-1789 ◽

Cited By ~ 5

Author(s):

Priyanka Katiyar ◽

Shraddha Mishra ◽

Anurag Srivastava ◽

N. Eswara Prasad

Keyword(s):

Electron Microscopy ◽

Contact Angle ◽

Flame Retardant ◽

Protective Clothing ◽

Sol Gel ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Water Contact ◽

Vis Spectroscopy ◽

Self Cleaning

TiO2, SiO2 and their hybrid nanocoatings are prepared on inherent flame retardant textile substrates from titanium(IV)iso-proproxide (TTIP) and tetraethoxysilane (TEOS) precursors using a sol–gel process followed by hydrothermal treatment. The coated samples are further functionalized by hexadecyltrimethoxysilane (HDTMS) to impart superhydrophobicity. Sample characterization of the nanosols, nanoparticles and coated samples are investigated using, X-ray diffractometer, transmission electron microscopy, scanning electron microscopy, UV-Vis spectroscopy, contact angle measurement. Stain degradation test under mild UV irradiation shows almost 54% degradation of coffee stain within 4 hours measured by Spectrophotometer. UV-Vis Absorption Spectroscopy demonstrates complete degradation of methyl orange colorant within 3 hours. Hybrid nanosol coated and HDTMS modified inherent flame retardant polyester surfaces show apparent water contact angle as ~145°, which is much closer to proximity of superhydrophobic surfaces. Thus, the novelty of present work is, by using sol–gel technique, a bi-functional textile surface has been developed which qualifies the very specific requirements of protective clothing like self-cleaning property (imparted by TiO2 nanoparticles) and superhydrophobicity (imparted by SiO2 nanoparticles and further surface modification by HDTMS), which are entirely contradictory in nature, in a single fabric itself. Thus developed textile surfaces also possess the other attributes of protective clothing like flame retardancy and air permeability.

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Application of Waterborne Acrylic and Solvent-Borne Polyester Coatings on Plasma-Treated Fir (Abies alba M.) Wood

Materials ◽

10.3390/ma15010370 ◽

2022 ◽

Vol 15 (1) ◽

pp. 370

Author(s):

Hadi Gholamiyan ◽

Behnam Gholampoor ◽

Reza Hosseinpourpia

Keyword(s):

Plasma Treatment ◽

Treated Wood ◽

Abies Alba ◽

Untreated Wood ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Accelerated Weathering ◽

Water Contact ◽

Before And After ◽

Carbon Dioxide Co2

This research investigates the effect of plasma treatment with air, nitrogen (N2), and carbon dioxide (CO2) gases on the performance of waterborne (acrylic) and solvent-borne (polyester) coated fir (Abies alba M.) wood samples. The properties of the plasma-coated samples were analyzed before and after exposure to accelerated weathering and compared with those of untreated and solely treated ones. According to pull-off testing, the coating adhesion of the wood samples was considerably improved by plasma treatment, and obvious differences were observed between different plasma gases. The effect was more pronounced after the weathering test. Similar results were obtained for the abrasion resistance of the samples. The water contact angle measurement illustrated more hydrophilic character in the solely plasma-treated wood in comparison with the untreated wood. The application of coatings, however, strongly improved its hydrophobic character. The performances of waterborne and solvent-borne coatings on plasma-treated wood were comparable, although slightly better values were obtained by the waterborne system. Our results exhibit the positive effect of plasma treatment on coating performances and the increased weather resistance of the waterborne and solvent-borne coating systems on plasma-treated wood.

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High Loading Capacity and Wear Resistance of Graphene Oxide/Organic Molecule Assembled Multilayer Film

Frontiers in Chemistry ◽

10.3389/fchem.2021.740140 ◽

2021 ◽

Vol 9 ◽

Author(s):

Li Chen ◽

Gang Wu ◽

Yin Huang ◽

Changning Bai ◽

Yuanlie Yu ◽

...

Keyword(s):

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Multilayer Films ◽

Thickness Measurement ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Film Structure ◽

Silicon Substrates ◽

Water Contact ◽

Macro Scale

Taking advantage of the strong charge interactions between negatively charged graphene oxide (GO) sheets and positively charged poly(diallyldimethylammonium chloride) (PDDA), self-assembled multilayer films of (GO/PDDA)n were created on hydroxylated silicon substrates by alternating electrostatic adsorption of GO and PDDA. The formation and structure of the films were analyzed by means of water contact angle measurement, thickness measurement, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). Meanwhile, tribological behaviors in micro- and macro- scale were investigated by AFM and a ball-on-plate tribometer, respectively. The results showed that (GO/PDDA)n multilayer films exhibited excellent friction-reducing and anti-wear abilities in both micro- and macro-scale, which was ascribed to the special structure in (GO/PDDA)n multilayer films, namely, a well-stacked GO–GO layered structure and an elastic 3D crystal stack in whole. Such a film structure is suitable for design molecular lubricants for MEMS and other microdevices.

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Surface Modification of Ultra-High Molecular Weight Polyethylene with Crosslinked Hyaluronic Acid and its Antiwear Performance

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.642.94 ◽

2015 ◽

Vol 642 ◽

pp. 94-98

Author(s):

Chau Chang Chou ◽

Yu Hsiang Hao ◽

Fu Yin Hsu

Keyword(s):

Molecular Weight ◽

Hyaluronic Acid ◽

High Molecular Weight ◽

Incident Light ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Coated Sample ◽

Infrared Spectrometry ◽

Water Contact ◽

Ultra High Molecular Weight

The surface of high-pressure crystallized ultra-high molecular weight polyethylene (UHMWPE) was modified for application as an artificial cartilage material. A UHMWPE surface pretreated by a series of processes, including treatment with O2-plasma and ethylenediamine solution, was coated with hyaluronic acid (HA). After that, adipic acid dihydrazide (AAD) was added to partially crosslink the HA coating in order to enhance its durability. The modified samples were verified by water contact angle measurement and Fourier transform infrared spectrometry. Both HA layers, original and crosslinked, were also quantitatively evaluated by carbohydrate chemistry assay according to the absorbance of the incident light. The tribological performance of the samples was evaluated by a pin-on-disk test rig lubricated by normal saline under an average pressure of 18 MPa and at a sliding speed of 0.03 m/s for 45 h. The wear resistance of the HA-coated UHMWPE specimens promoted by the crosslink process was superior to that of the original HA-coated sample, and that resistance was maintained after immersion in saline solution for one month.

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An Influence of Oxygen Flow Rate on Structural, Optical and Tribological Properties of Molybdenum Oxide Thin Films

Advanced Engineering Forum ◽

10.4028/www.scientific.net/aef.39.43 ◽

2021 ◽

Vol 39 ◽

pp. 43-53

Author(s):

Divyeshkumar P. Dave ◽

Akshay M. Patel ◽

Kamlesh V. Chauhan ◽

Sushant K. Rawal

Keyword(s):

Wear Rate ◽

Molybdenum Oxide ◽

Tribological Properties ◽

Flow Rate ◽

Gas Flow ◽

Visible Region ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Oxygen Flow Rate ◽

Oxygen Flow

The influence of oxygen flow rate is examined on structural, optical and tribological properties of molybdenum oxide films deposited by reactive magnetron sputtering. The films were characterized by X-ray diffraction, scanning electron microscope (SEM), and contact angle measurement system. The optical properties of the films were measured by UV-Vis-NIR spectrophotometer and transmittance of ∼73% in the visible region of the spectrum was achieved. The band gap increases with increases in oxygen gas flow rate. AFM figure illustrates that the roughness of surface increases as oxygen flow rate increases. As oxygen increases wear rate and COF decreases while at the 18 sccm the lowest wear rate found.

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