scholarly journals Evaluation of the particle size of organosolv lignin in the synthesis of resol resins for plywood and their performance on fire spreading

TAPPI Journal ◽  
2017 ◽  
Vol 16 (7) ◽  
pp. 409-416 ◽  
Author(s):  
ELECTRA PAPADOPOULOU ◽  
SOTIRIS KOUNTOURAS ◽  
KONSTANTINOS CHRISSAFIS ◽  
MIKELIS KIRPLUKS ◽  
UGIS CABULIS ◽  
...  
Keyword(s):  
Particle Size ◽  
Phenol Formaldehyde ◽  
Industrial Process ◽  
Synthesis Process ◽  
Cone Calorimetry ◽  
Scanning Calorimetry ◽  
State Institute ◽  
Phenolic Resins ◽  
Substitution Level ◽  
Organosolv Lignin

Scientists today are intensively seeking alternatives to petrochemical materials. Among others, lignin is a promising candidate because it is available in large quantities while its chemical structure makes its use possible in a variety of chemical reactions. Lignin, received by numerous methods from various feedstocks, is a promising material for the synthesis of many products like active carbon, thermosetting and thermoplastic polymers, surfactants, phenolic chemicals, etc. In this paper, the potential of using Biolignin – a trademarked organosolv lignin from straw prepared by Compagnie Industrielle de la Matière Végétale (CIMV; Neuilly-sur-Seine, France) – in the synthesis of phenol-formaldehyde (PF) resins was studied by CHIMAR HELLAS S.A. (Kalamaria, Greece). Before its use, Biolignin was further purified and subjected to mechanical treatment for the reduction of its particle size in order to increase its reactivity. The effectiveness of the treatment was verified by atomic force microscopy (AFM) measurements that were carried out by SYNPO Company (Pardubice, Czech Republic). Resol phenolic resins were prepared with various substitution levels of phenol up to 80%. However, their synthesis process was smooth only up to the substitution level of 50%. The properties of the resins were determined with typical lab analysis. Their thermal behavior was studied with differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) measurements that were conducted by the Aristotle University of Thessaloniki in Greece. Their bonding ability was evaluated by CHIMAR HELLAS via their application in the production of plywood panels of three layers that were prepared following a simulation of the industrial process. The panels were tested for their properties according to the relevant European standards, while their performance relative to fire was studied with cone calorimetry measurements that were performed by the Latvian State Institute of Wood Chemistry (LIWC; Riga, Latvia). All results were compared with that of a typical PF resin. It was found that the particle size of lignin affects the performance of the resins, while lignin-based PF resins are suitable for the production of plywood panels and have somewhat better performance relative to fire than typical PF resins. This study has been performed within the framework of the European project BIOCORE (biocommodity refinery for biofuels, chemical intermediates, polymers and materials).

scholarly journals Synthesis and thermal properties of some phenolic resins

2019 ◽  
Vol 7 (1) ◽  
pp. 1-15
Author(s):  
Alshawi F M ◽  
Abdul Razzq K ◽  
Hanoosh W S
Keyword(s):  
Phenol Formaldehyde ◽  
Chemical Properties ◽  
Decomposition Temperature ◽  
Industrial Applications ◽  
Stability Study ◽  
Curing Temperature ◽  
Molar Ratio ◽  
Scanning Calorimetry ◽  
Phenolic Resins ◽  
Physical And Chemical

Introduction: Phenolic resins have been in use since the early twentieth century and are considered the first class of synthetic polymers to achieve commercial success, moreover phenolic resins continue to succeed and attract special interest in a large range of industrial applications such as adhesives, paints, and composites; because of their unique physical and chemical properties. Materials and Methods: Prepolymers resol resins (RR, RH, RP, and RC) were synthesized by the reaction of phenolic compounds (resorcinol, hydroquinone, phloroglucinol, and catechol) respectively, with formaldehyde at molar ratio phenol/ formaldehyde 1/1.5, using sodium hydroxide as a catalyst. These resins were characterized by FTIR. The curing reaction of these resins was evaluated using differential scanning calorimetry (DSC), while the thermal stability study was evaluated using thermogravimetric analysis (TGA). Results and Discussion:From the results showing that these prepolymers have different curing temperatures and curing energy, while the TGA study showed that the cured resins have decomposition temperature more than 300 ºC, and char residue at 650 ºC more than 60%. Conclusions: These resol resins have different gel times (8-55) min, and viscosities (435-350) mpa.s. The curing temperature of these resin obtained from DSC curves was (120, 129, 105 and 127 °C), while the thermal behavior of the cured resins obtained from TGA curves showed that these cured resin have two decomposition temperatures and the rate of decomposition in the order of RC < RR< .

scholarly journals Synthesis of lignin-based phenol-formaldehyde adhesive - A sustainable alternative to petrochemical

2021 ◽  
Vol 13 (3) ◽  
pp. 48-57
Author(s):  
Thi Nhu Y Nguyen ◽  
Thi Yen Nhi Nguyen ◽  
Thi Minh Thu Tran ◽  
Thi Ven Nguyen ◽  
Nguyen Phuong Lan Tran ◽  
...  
Keyword(s):  
Reaction Time ◽  
Reaction Temperature ◽  
Bending Strength ◽  
Phenol Formaldehyde ◽  
Tensile Modulus ◽  
Mekong Delta ◽  
Solid Content ◽  
Synthesis Process ◽  
Scanning Calorimetry ◽  
Synthetic Process

This study is to investigate the capability of producing lignin-based phenol-formaldehyde adhesive (LBPFA) with lignin derived from coir pith collected in the Mekong Delta, Viet Nam. The LBPFA synthetic process underwent non chemical modifications to minimize petrochemicals and energy. Effective factors as reaction time, reaction temperature and various lignin contents of phenol substitution were examined. Physical, chemical and thermal properties containing formaldehyde content, viscosity, solid content, Fourier transformed infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), tensile strength, tensile modulus and tensile strain were conducted. LBPFA was successfully synthesized at various levels of lignin contents substituting for phenol. The LBPFA’s parameters were in accordance with GB/T14372-2006 standard. The optimum reaction time, reaction temperature and lignin replacement content for LBPFA synthesis process were identified at 180 minutes, 900C and 40% wt/wt, respectively. The LBPFA showed the highest dry and wet tensile strengths of 14.42 MPa and 7.66 MPa on wooden boards compared to corresponding figures of commercial resin with 2.98 MPa and 0 MPa, respectively. For plywood, bending strength shown in LBPFA and commercial adhesive were 15.97 MPa and 20.16 MPa, respectively.

Optimasi Proses Pembuatan dan Karakterisasi Fisik Niosom Sinkonin

2019 ◽  
Vol 16 (2) ◽  
pp. 178
Author(s):  
Hariyanti Hariyanti ◽  
Sophi Damayanti ◽  
Sasanti Tarini
Keyword(s):  
Differential Scanning Calorimetry ◽  
Particle Size ◽  
Hair Follicle ◽  
Scanning Calorimetry ◽  
Span 60

Sinkonin praktis tidak larut dalam air, sedikit larut dalam kloroform dan alkohol. Hal ini berdampak pada rendahnya penetrasi transfollicular sinkonin, karena hanya bahan aktif hidrofilik yang mampu melewati hair follicle. Dengan demikian dibutuhkan satu sistem penghantaran yang mampu menurunkan hidrofobisitas sinkonin untuk meningkatkan penetrasi sinkonin ke follicle. Niosom merupakan vesikel ampifilik dengan struktur lapisan rangkap yang terbentuk dari hidrasi kombinasi surfaktan nonionik dan kolesterol yang mampu menurunkan hidrofobisitas sinkonin. Penelitian ini bertujuan untuk menentukan proses pembuatan niosom sinkonin yang optimum. Pembuatan niosom sinkonin diawali dengan menentukan temperatur gelasi (Tg) dari span 60 dengan Differential Scanning Calorimetry (DSC), kemudian dilanjutkan dengan optimasi proses meliputi: optimasi kecepatan rotavapor pembentukan film lapis tipis, temperatur hidrasi, kecepatan rotavapor hidrasi, waktu hidrasi, dan waktu sonikasi. Karakteristik vesikel niosom yang optimal meliputi: ukuran partikel dan indeks polidispersitas dengan menggunakan Particle Size Analized (PSA) serta efisiensi penjeratan sinkonin dengan menggunakan KCKT. Temperatur gelasi (Tg) span 60 45±2 oC, kecepatan rotavapor pembentukan film lapis tipis niosom 210 rpm, temperatur hidrasi 55±2 oC, kecepatan rotavapor hidrasi 210 rpm, waktu hidrasi 20 menit, waktu sonikasi suspensi niosom 1 menit. Ukuran vesikel yang diperoleh adalah 100–200 nm, indeks polidispersitas 0,2–0,4 dan efisiensi penjeratan niosom sinkonin 84,49±0,0025%. Proses pembuatan niosom sinkonin memiliki pengaruh besar terhadap hasil ukuran vesikel dan efisiensi penjeratan niosom sinkonin.

Chitosan nanoparticles for tamoxifen delivery and cytotoxicity to MCF-7 and Vero cells

2011 ◽  
Vol 83 (11) ◽  
pp. 2027-2040 ◽  
Author(s):  
Neralakere Ramanna Ravikumara ◽  
Basavaraj Madhusudhan
Keyword(s):  
Particle Size ◽  
Chitosan Nanoparticles ◽  
Vero Cells ◽  
In Vitro Cytotoxicity ◽  
Correlation Spectroscopy ◽  
Scanning Calorimetry ◽  
Ζ Potential ◽  
Human Red Blood Cells ◽  
Tamoxifen Citrate

In this study, tamoxifen citrate-loaded chitosan nanoparticles (tamoxcL-ChtNPs) and tamoxifen citrate-free chitosan nanoparticles (tamoxcF-ChtNPs) were prepared by an ionic gelation (IG) method. The physicochemical properties of the nanoparticles were analyzed for particle size, zeta (ζ) potential, and other characteristics using photon correlation spectroscopy (PCS), zeta phase analysis light scattering (PALS), scanning electron microscopy (SEM), Fourier transform infrared (FTIR), and differential scanning calorimetry (DSC). The variation in particle size was assessed by changing the concentration of chitosan, pentasodium tripolyphosphate (TPP), and the pH of the solution. The optimized tamoxcL-ChtNPs showed mean diameter of 187 nm, polydispersity of 0.125, and ζ-potential of +19.1 mV. The encapsulation efficiency (EE) of tamoxifen citrate (tamoxc) increased at higher concentrations, and release of tamoxc from the chitosan matrix displayed controlled biphasic behavior. Those tamoxcL-ChtNPs tested for chemosensitivity showed dose- and time-dependent antiproliferative activity of tamoxc. Further, tamoxcL-ChtNPs were found to be hemocompatible with human red blood cells (RBCs) and safe by in vitro cytotoxicity tests, suggesting that they offer promise as drug delivery systems in therapy.

A Convenient Method for Preparing Well-Dispersed Er2Zr2O7 Nanocrystals

2010 ◽  
Vol 123-125 ◽  
pp. 611-614 ◽  
Author(s):  
Yu Ping Tong ◽  
Rui Zhu Zhang ◽  
Shun Bo Zhao ◽  
Chang Yong Li
Keyword(s):  
Particle Size ◽  
Combustion Synthesis ◽  
Crystal Size ◽  
Lattice Distortion ◽  
Combustion Method ◽  
Treatment Temperature ◽  
Synthesis Process ◽  
Thermal Treatment Temperature ◽  
Average Size ◽  
Xrd And Tem

Well-dispersed fluorite Er2Zr2O7 nanocrystals have been successfully prepared by a convenient salt-assistant combustion method. The effects of calcinations temperature and salt category on the characteristics of the products were investigated by XRD and TEM. The thermal treatment temperature has an important effect on crystal size and lattice distortion of the nanocrystals. The experiment showed that the introduction of salt in the combustion synthesis process resulted in the formation of well-dispersed Er2Zr2O7 nanocrystals. The average size was 30 nm and was in agreement with the XRD result, which indicated that the nanocrystals were uniform in particle size distribution. Moreover, the possible formation process in the salt-assisted combustion synthesis was also analyzed.

Melting and Oxidation of Nanometer Size Aluminum Powders

2005 ◽  
Vol 896 ◽  
Author(s):  
Mikhaylo A Trunov ◽  
Swati Umbrakar ◽  
Mirko Schoenitz ◽  
Joseph T Mang ◽  
Edward L Dreizin
Keyword(s):  
Particle Size ◽  
Oxidation Behavior ◽  
Melting Behavior ◽  
Size Distributions ◽  
Particle Size Distributions ◽  
Scanning Calorimetry ◽  
Aluminum Powders ◽  
Melting Temperatures ◽  
X Ray Scattering ◽  
Powder Samples

AbstractRecently, nanometer-sized aluminum powders became available commercially and their use as potential additives to propellants, explosives, and pyrotechnics has attracted significant interest. It has been suggested that very low melting temperatures are expected for nano-sized aluminum powders and that such low melting temperatures could accelerate oxidation and trigger ignition much earlier than for regular, micron-sized aluminum powders. The objective of this work was to investigate experimentally the melting and oxidation behavior of nano-sized aluminum powders. Powder samples with three different nominal sizes of 44, 80, and 121 nm were provided by Nanotechnologies Inc. The particle size distributions were measured using small angle x-ray scattering. Melting was studied by differential scanning calorimetry where the powders were heated from room temperature to 750 °C in argon environment. Thermogravimetric analysis was used to measure the mass increase indicative of oxidation while the powders were heated in an oxygen-argon gas mixture. The measured melting curves were compared to those computed using the experimental particle size distributions and thermodynamic models describing the melting temperature and enthalpy as functions of the particle size. The melting behavior predicted by different models correlated with the experimental observations only qualitatively. Characteristic step-wise oxidation was observed for all studied nanopowders. The observed oxidation behavior was well interpreted considering the recently established kinetics of oxidation of micron-sized aluminum powders. No correlation was found between the melting and oxidation of aluminum nanopowders.

Influence of the particle size on the physical, mechanical and tribological properties of composites for brake pads

2021 ◽  
pp. 36-40
Author(s):  
F.F. Yusubov
Keyword(s):  
Particle Size ◽  
Composite Materials ◽  
Tribological Properties ◽  
Friction And Wear ◽  
Phenol Formaldehyde ◽  
Environmentally Friendly ◽  
Brake Pads ◽  
Mechanical And Tribological Properties ◽  
Pin On Disk ◽  
Properties Of Composites

Tribotechnical indicators of environmentally friendly frictional composite materials with phenol-formaldehyde matrix are studied. Friction tests were carried out on a MMW-1 vertical tribometer according to the pin-on-disk scheme. Keywords: brake pads, composites, friction and wear, plasticizers, degradation, porosity. [email protected]

Formulation and Evaluation of Benidipine Nanosuspension

2021 ◽  
pp. 4111-4116
Author(s):  
Sejal Patel ◽  
Anita P. Patel
Keyword(s):  
Particle Size ◽  
Water Solubility ◽  
Polymer Concentration ◽  
Oral Route ◽  
Water Soluble ◽  
In Vitro Dissolution ◽  
Scanning Calorimetry ◽  
23 Factorial Design ◽  
Selection Of

In the interest of administration of dosage form oral route is most desirable and preferred method. After oral administration to get maximum therapeutic effect, major challenge is their water solubility. Water insoluble drug indicate insufficient bioavailability as well dissolution resulting in fluctuating plasma level. Benidipine (BND) is poorly water soluble antihypertensive drug has lower bioavailability. To improve bioavailability of Benidipine HCL, BND nanosuspension was formulated using media milling technique. HPMC E5 was used to stabilize nanosuspension. The effect of different important process parameters e.g. selection of polymer concentration X1(1.25 mg), stirring time X2 (800 rpm), selection of zirconium beads size X3 (0.4mm) were investigated by 23 factorial design to accomplish desired particle size and saturation solubility. The optimized batch had 408 nm particle size Y1, and showed in-vitro dissolution Y2 95±0.26 % in 30 mins and Zeta potential was -19.6. Differential scanning calorimetry (DSC) and FT-IR analysis was done to confirm there was no interaction between drug and polymer.

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