scholarly journals Research on preparation of phosphate-modified animal glue binder for foundry use

2018 ◽  
Vol 5 (3) ◽  
pp. 171795
Author(s):  
Tian-Shu Wang ◽  
Wei-Hua Liu ◽  
Ying-Min Li

In this paper, three phosphates were used as modifiers to modify animal glue binder. The structural characteristics and thermal properties of animal glue binder treated with phosphates were studied by Fourier transform-infrared spectroscopy, gel permeation chromatography and derivative thermogravimetric analysis. The results showed that the modified animal glue binder had better sand tensile strength and lower viscosity than untreated animal glue binder. The best modification process was as follows: the optimal amount of sodium carbonate was 4 wt% to animal glue; the optimal weight ratio of the modifiers was sodium pyrophosphate : sodium tripolyphosphate : sodium hexametaphosphate : animal glue = 3 : 3 : 4 : 100, and the optimal reaction should be performed at 80°C for a reaction time of 120 min. A final tensile strength of approximately 3.20 MPa was achieved and the viscosity value was approximately 880 mPa s.

Pharmaceutics ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 608
Author(s):  
Csilla Bartos ◽  
Patrícia Varga ◽  
Piroska Szabó-Révész ◽  
Rita Ambrus

The absorption of non-steroidal anti-inflammatory drugs (NSAIDs) through the nasal epithelium offers an innovative opportunity in the field of pain therapy. Thanks to the bonding of chitosan to the nasal mucosa and its permeability-enhancing effect, it is an excellent choice to formulate microspheres for the increase of drug bioavailability. The aim of our work includes the preparation of spray-dried cross-linked and non-cross-linked chitosan-based drug delivery systems for intranasal application, the optimization of spray-drying process parameters (inlet air temperature, pump rate), and the composition of samples. Cross-linked products were prepared by using different amounts of sodium tripolyphosphate. On top of these, the micrometric properties, the structural characteristics, the in vitro drug release, and the in vitro permeability of the products were studied. Spray-drying resulted in micronized chitosan particles (2–4 μm) regardless of the process parameters. The meloxicam (MEL)-containing microspheres showed nearly spherical habit, while MEL was present in a molecularly dispersed state. The highest dissolved (>90%) and permeated (~45 µg/cm2) MEL amount was detected from the non-cross-linked sample. Our results indicate that spray-dried MEL-containing chitosan microparticles may be recommended for the development of a novel drug delivery system to decrease acute pain or enhance analgesia by intranasal application.


2021 ◽  
Vol 55 (2) ◽  
pp. 331-349
Author(s):  
Hannes Orelma ◽  
Atsushi Tanaka ◽  
Maija Vuoriluoto ◽  
Alexey Khakalo ◽  
Antti Korpela

AbstractTraditional particle board can generate harmful indoor air emissions due to the volatile resin-based compounds present. This study investigated the preparation of sawdust particle board using the novel ionic liquid based fusion approach with [EMIM]OAc. The dissolution parameters were investigated using the thermal optical microscopy technique. The particle board sheets were prepared by hot pressing sawdust in the presence of ionic liquid (IL) ([EMIM]OAc) and subsequently purifying the fusion sawdust matrix from the IL with methanol. The fusion process of the sawdust particles was analysed with SEM and mechanical testing. The raw materials and the produced materials were investigated with elemental analysis, FTIR, and 13C-SS-NMR. IL fusion of the sawdust required a temperature above 150 °C, similar to the glass transition temperature (tg) of lignin. At lower temperatures, strong particle fusion was not obtained. It was observed that the sawdust/IL weight ratio was an important parameter of the fusion process, and a 1:3 weight ratio resulted in the strongest particle boards with a tensile strength of up to 10 MPa, similar to commercial particle boards. The particle fusion process was also studied with a twin-screw extruder. The extrusion enhanced the fusion of the sawdust particles by increasing dissolution of the sawdust particles, which was subsequently seen in elevated tensile strength (20 MPa). The study provides a practical view of how sawdust-based particle board can be manufactured using ionic liquid-based fusion.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Yongfang Qian ◽  
Zhen Zhang ◽  
Laijiu Zheng ◽  
Ruoyuan Song ◽  
Yuping Zhao

Design and fabrication of nanofibrous scaffolds should mimic the native extracellular matrix. This study is aimed at investigating electrospinning of polycaprolactone (PCL) blended with chitosan-gelatin complex. The morphologies were observed from scanning electron microscope. As-spun blended mats had thinner fibers than pure PCL. X-ray diffraction was used to analyze the degree of crystallinity. The intensity at two peaks at 2θof 21° and 23.5° gradually decreased with the percentage of chitosan-gelatin complex increasing. Moreover, incorporation of the complex could obviously improve the hydrophilicity of as-spun blended mats. Mechanical properties of as-spun nanofibrous mats were also tested. The elongation at break of fibrous mats increased with the PCL content increasing and the ultimate tensile strength varied with different weight ratios. The as-spun mats had higher tensile strength when the weight ratio of PCL to CS-Gel was 75/25 compared to pure PCL. Both as-spun PCL scaffolds and PCL/CS-Gel scaffolds supported the proliferation of porcine iliac endothelial cells, and PCL/CS-Gel had better cell viability than pure PCL. Therefore, electrospun PCL/Chitosan-gelatin nanofibrous mats with weight ratio of 75/25 have better hydrophilicity mechanical properties, and cell proliferation and thus would be a promising candidate for tissue engineering scaffolds.


2020 ◽  
Vol 15 (4) ◽  
Author(s):  
Mahesh Mallampati ◽  
Sreekanth Mandalapu ◽  
Govidarajulu C

The composite materials are replacing the traditional materials because oftheir superior properties such as high tensile strength, low thermal expansion, high strength to weight ratio, low cost, lightweight, high specific modulus, renewability and biodegradability which are the most basic & common attractive features of composites that make them useful for industrial applications. The developments of new materials are on the anvil and are growing day by day. The efforts to produce economically attractive composite components have resulted in several innovative manufacturing techniques currently being used in the composites industry. Generally, composites consist of mainly two phases i.e., matrix and fiber. In this study, woven roving mats (E-glass fiber orientation (-45°/45°,0°/90°, - 45°/45°),UD450GSM)were cut in measured dimensions and a mixture of Epoxy Resin (EPOFINE-556, Density-1.15gm/cm3), Hardener (FINE HARDTM 951, Density- 0.94 gm/cm3) and Acetone [(CH3)2CO, M= 38.08 g/mol] was used to manufacture the glass fiber reinforced epoxy composite by hand lay-up method. Mechanical properties such as tensile strength, SEM analysis, hardness test, density tests are evaluated.


Foods ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2375
Author(s):  
Yayuan Tang ◽  
Jinfeng Sheng ◽  
Xuemei He ◽  
Jian Sun ◽  
Zhen Wei ◽  
...  

There have been few studies dealing with chemical elucidation and pharmacological potentials of water-soluble polysaccharides from jasmine tea, limiting their use in functional foods. In this study, water-soluble polysaccharides (named as JSP) were extracted from Jasminum sambac (L.) Aiton tea and fractionated to afford two sub-fractions (JSP-1 and JSP-2). The main structural characteristics of novel JSP sub-fractions were determined by high performance gel permeation chromatography, ultra-performance liquid chromatography-tandem mass spectrometry, Fourier transform infrared, and nuclear magnetic resonance analysis. Physiologically, the abilities of JSP-1 and JSP-2 to reduce ferric ions, scavenge DPPH and hydroxyl radicals, as well as protect islet cells were confirmed in vitro. JSP-1 exhibited better antioxidant and hypoglycemic activities than JSP-2. The molecular weights of JSP-1 and JSP-2 were 18.4 kDa and 14.1 kDa, respectively. JSP-1 was made up of glucose, galactose, rhamnose, xylose, arabinose, and galacturonic acid with molar ratios 1.14:4.69:1.00:9.92:13.79:4.09, whereas JSP-2 with a triple helical structure was composed of galactose, rhamnose, xylose, arabinose, and galacturonic acid as 3.80:1.00:8.27:11.85:5.05 of molar ratios. JSP-1 contains →1)-α-Galƒ-(3→, →1)-α-Galƒ-(2→, →1)-α-Araƒ-(5→, →1)-α-Araƒ-(3→, →1)-α-Araƒ-(3,5→, →1)-β-Xylp-(2→ and →1)-β-Xylp-(3→ residues in the backbone. These results open up new pharmacological prospects for the water-soluble polysaccharides extracted from jasmine tea.


2021 ◽  
Vol 11 ◽  
Author(s):  
Hui Jia ◽  
Bin Zhao ◽  
Fangfang Zhang ◽  
Ramesh Kumar Santhanam ◽  
Xinying Wang ◽  
...  

Polysaccharides are the main active ingredients of ginseng. To extract the most effective polysaccharides against hepatocellular carcinoma (HCC), we isolated and characterized the polysaccharides from the mountain cultivated ginseng (MCG) and compared their composition and cytotoxic effect with cultivated ginseng (CG) polysaccharide against HepG2 cell lines for the first time. MCG polysaccharides and CG polysaccharides were fractionated into two fractions such as MTPS-1, MTPS-2 and CTPS-1, CTPS-2 by salting out, respectively. Compared to CG, MCG possessed appreciable cytotoxic effect against HepG2 cells among that MTPS-1 possess fortified effect. Then, MTPS-1 was selected for further isolation process and seven acidic polysaccharides (MCGP-1–MCGP-7) were obtained using ethanol precipitation, ion-exchange, and gel permeation chromatography techniques. Structural characteristics of the polysaccharides (MCGP-1–MCGP-7) were done by adapting methylation/GC-MS and NMR analysis. Overall, MCGP-3 polysaccharide was found to possess significant cytotoxic effect against HepG2 cells with the IC50 value.


Vestnik MGSU ◽  
2020 ◽  
pp. 824-833
Author(s):  
Linar N. Talipov ◽  
Evgeny G. Velichko ◽  
Vyacheslav S. Semenov

Introduction. Corrosion of reinforcement in concrete structures is rather expensive for the economy of any country. Current statutory documents offer two main directions — primary and secondary protection. One of the promising areas of primary protection methods is the use of complex anti-corrosion additives in concrete due to its technological simplicity and economic efficiency. Passivators and surfactants (SAS), as components of such additives, are of particular interest. Sodium nitrite is offered as a passivator, and polycarboxylate molecules (PCE) — as a SAS. The additive of sodium nitrite together with PCE has a visual synergistic effect. Materials and methods. Identification of structural characteristics of the molecules of the obtained PCE polymers was determined by methods of exclusion gel-permeation chromatography and 13C NMR spectroscopy. To study the synergetic effect of NaNO2 + PCE additive, the samples were kept in the models of pore liquid, after which the morphology of their surface was studied by methods of scanning electron microscopy and electron probe microanalysis. Results. The texture and surface color of the presented micrographs indicate surface formations on the samples stored in the models of pore liquid with different anti-corrosion additives. Electron probe microanalysis showed increased concentrations of carbon, oxygen and sodium on the surface of samples stored in pore concrete liquid models with the addition of a complex anti-corrosion additive of sodium nitrite and PCE, which indicates increased concentrations of PCE and possible increased pH on the steel surface. Based on the data acquired, the mechanism of formation of a protective film layer using complex anti-corrosion additive NaNO2 + PCE is offered. Conclusions. Justification of synergetic effect of complex polycarboxylate anti-corrosion additive in the model of concrete pore liquid opens up prospects for research of such additives to the concrete model.


2018 ◽  
Vol 21 (1) ◽  
pp. 147 ◽  
Author(s):  
Sihama I. Salih ◽  
Qahtan A. Hamad ◽  
Safaa N. Abdul Jabbar ◽  
Najat H. Sabit

This work covers mixing of unsaturated polyester (un- polyester) with starch powders as polymer blends and study the effects of irradiation by UV-acceleration on mechanical properties of its. The unsaturated polyester was mixing by starch powders at particle size less than (45 µm) at selected weight fraction of (0, 0.5, 1, 1.5, 2, 2.5 and 3%). These properties involve ultimate tensile strength, modulus of elasticity, elongation percentage, flexural modulus, flexural strength, fracture toughness, impact strength and hardness. The results illustrate decrease in the ultimate tensile strength at and elongation percentage, while increasing modulus of elasticity, with increasing the weight ratio of starch powder to 3 % weight fraction, whereas the maximum value of hardness and flexural, impact properties happened at 1 % weight fraction for types of polymer blends.


2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Chen-chen Fan ◽  
Qian Tang

This paper aims to develop a modified animal glue sand binder for foundry casting with improved water resistance and bonding strength. An efficient method is reported by using sodium hydroxide as the catalyst to improve the operability of animal glue binder and allyl glycidyl ether as the modifier to improve the water resistance and bonding strength. Sand specimens prepared using allyl glycidyl ether-modified animal glue binder were cured by compressed air at room temperature. The proposed method saves energy and is environmentally friendly and inexpensive. Compared with unmodified animal glue binder, standard dog bone sand specimens with allyl glycidyl ether-modified animal glue binder had higher tensile strength of 2.58 MPa, flowability of 1.95 g, better water resistance (a lower decrease in tensile strength at 25 °C and relative humidity of 60%), and good collapsibility. This allyl glycidyl ether-modified animal glue binder is suitable for practical application in the foundry industry.


2013 ◽  
Vol 8 (1) ◽  
pp. 155892501300800
Author(s):  
Jia-Horng Lin ◽  
Chen-Hung Huang ◽  
Ching-Wen Lin ◽  
Ching Wen Lou

In this research, we create a PET/TPU/PU composite base fabric from a PET nonwoven base fabric, a TPU honeycomb grid, and a PU foam plank. First, the PET base fabric is made from 7D three-dimensional-hollow-crimp fiber (7D PET) and low-melting-point (low-Tm) fibers with weight ratio and number of lamination layers as the parameters. The hardness and rebound resilience rate of the PET nonwoven base fabric are 71% and 63.5%, respectively. The PET nonwoven base fabric's optimum air permeability is 240 cm3/s/cm2. The maximum tensile strength of the PET nonwoven base fabric with 9 layers of lamination is 39.8 kg/cm2, and when the weight ratio is either 4:6 or 3:7, changes to 40 kg/cm2. The PET/TPU/PU composite base fabric has a LOI of 33 when the number of lamination layers is 10, or when the low-Tm fiber content is 50%; the composite base fabric's average optimum thermal conductivity is 0.914 W/mK.


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