Synthesis of Formaldehyde Free Amino Resin to Produce Green Eco-Labelled Leather with Improved Retanning Properties

2020 ◽  
Vol 115 (4) ◽  
pp. 132-139
Author(s):  
Muhammad Naveed Ashraf ◽  
Shahzad Maqsood Khan ◽  
Shahid Munir ◽  
Rashid Saleem
Keyword(s):  
Thermal Stability ◽  
Water Solubility ◽  
Thermo Gravimetric Analysis ◽  
Sulfanilic Acid ◽  
Gravimetric Analysis ◽  
Melamine Resin ◽  
Organoleptic Properties ◽  
Formaldehyde Content ◽  
Leather Processing ◽  
Percentage Efficiency

Formaldehyde has many applications in the chemical industry including synthesis of amino resins which are used in leather processing. After application in leather, these resins are hydrolyzed under certain conditions to release free formaldehyde which has high environmental concerns due to its proven carcinogenic effects. The objective of this work is to develop a formaldehyde free melamine-based resin to produce green leather with improved retanning properties and thermal stability. The optimum melamine resin was synthesized by condensing melamine with glyoxal instead of formaldehyde. Further, the water solubility and improved thermal stability of synthesized melamine resins were achieved by introduction of sulfanilic acid in resin structure. Synthesized resin was used in leather retanning in comparison with commercially available melamine resin as a control. Both leathers were tested for mechanical properties, organoleptic properties, grain surface and fiber structure analysis. Comparative free formaldehyde content was measured in resultant leathers. Effluents of retanning baths were comparatively analyzed. Optimum resin was also characterized by thermo gravimetric analysis and FTIR. The results of this study showed that the experimental resin has imparted significant improvement in mechanical and organoleptic properties of leather as compared to the control resin. Analysis of free formaldehyde content confirmed the absence of free formaldehyde in leather treated with optimum resin while 141 mg/kg formaldehyde was detected in leather treated with control resin. Free formaldehyde was also absent in effluent of experimental resin while 305 mg/kg formaldehyde was detected in effluent of control resin. Moreover, percentage efficiency in COD, TDS and TSS load of effluent was observed as 9.62, 7.2 and 6.31 respectively.  Resultant leather was free from formaldehyde making it safe for human along with reduction in pollution load of tannery.  

Effect of Alkali and Silane Treatment on the Thermal Stability of Hemp Fibers as Reinforcement in Composite Structures

2011 ◽  
Vol 415-417 ◽  
pp. 666-670 ◽  
Author(s):  
Na Lu ◽  
Shubhashini Oza ◽  
Ian Ferguson
Keyword(s):  
Thermal Stability ◽  
Composite Structures ◽  
Natural Fiber ◽  
Alkali Treatment ◽  
Thermo Gravimetric Analysis ◽  
Natural Fibers ◽  
Gravimetric Analysis ◽  
Silane Treatment ◽  
Hemp Fibers ◽  
Thermal Stability Of

Natural fiber reinforced composites are being used as reinforcement material in composite system due to their positive environmental benefits. Added to that, natural fibers offer advantages such as low density, low cost, good toughness, high specific strength, relatively non-abrasive and wide availability. However, the low thermal stability of natural fibers is one of the major challenges to increase their use as reinforcing component. In this study, a thorough investigation has been done to compare the effect of two chemical treatment methods on the thermal stability of hemp fibers. 5wt% sodium hydroxide and 5wt% triethoxyvinylsilane was used for the treatment of hemp fibers. Fourier transform infrared spectroscopy, scanning electron microscopy and thermo gravimetric analysis were used for characterization of untreated and treated fiber. The results indicated that 24 hours alkali treatment and 3 hours silane treatment time enhanced the thermal stability of the hemp fiber. However, alkali treatment shows better improvement compared to silane treatment.

Effect of boron-nitrogen modified soybean oil additive on biodegradability, anti-oxidation property, and lubricity of rapeseed oil

2019 ◽  
Vol 234 (2) ◽  
pp. 282-291 ◽  
Author(s):  
Ping Liu ◽  
Xin Wang ◽  
Jiang Wu ◽  
Wang Lin ◽  
Yanhan Feng ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Soybean Oil ◽  
Rapeseed Oil ◽  
Energy Dispersive Spectrometer ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Modified Soybean Oil ◽  
Wear And Friction ◽  
Friction Reducing ◽  
Boron Nitrogen

Two novel boron-nitrogen modified soybean oil additives with different length of chain structures (abbreviated as BNS1 and BNS2) were synthesized. The thermal stability of BNS1 and BNS2 was evaluated by thermo-gravimetric analysis. The effect of the as-synthesized additives on the biodegradability, anti-oxidation property, and lubricity in rapeseed oil was evaluated by respective standard method. Moreover, the morphology and tribochemical characteristics of the worn surfaces were examined by scanning electron microscope assembled with energy dispersive spectrometer. The results indicated that BNS1 and BNS2 both possess good thermal stability; BNS1 slightly impairs the biodegradability of rapeseed oil, but BNS2 facilitates the biodegradability of rapeseed oil. BNS1 and BNS2 could improve the anti-wear and friction-reducing performance of the rapeseed oil, but BNS1 exhibited better anti-wear ability as compared to that of BNS2, BNS2 exhibited better anti-wear ability in reducing friction coefficients as compared to that of BNS1. The enhanced anti-wear and friction-reducing abilities of rapeseed oil were ascribed to the formation of a composite boundary lubrication film due to the strong adsorption of BNS1 or BNS2 and rapeseed oil onto the lubricated surfaces and their tribochemical reactions with metal surfaces. BNS1 and BNS2 could both facilitate the anti-oxidation properties of the rapeseed oil.

Palm Kernel Shell Filled Recycled High-Density Polyethylene: Effect of Filler Loading

2016 ◽  
Vol 857 ◽  
pp. 191-195 ◽  
Author(s):  
A. Nadiatul Husna ◽  
Bee Ying Lim ◽  
H. Salmah ◽  
Chun Hong Voon
Keyword(s):  
Thermal Stability ◽  
High Density Polyethylene ◽  
Thermo Gravimetric Analysis ◽  
Palm Kernel ◽  
Filler Loading ◽  
High Density ◽  
Gravimetric Analysis ◽  
Melt Mixing ◽  
Palm Kernel Shell ◽  
Thermal Stability Of

Palm kernel shells (PKS) filled recycled high density polyethylene (rHDPE) biocomposites were produced using melt mixing. The biocomposites were prepared on Brabender Plasticorder at temperature of 185 °C and rotor speed of 50 rpm by varying filler loading (0 to 40 phr). In this study, the effect of PKS loading on rheological properties and thermal stability of rHDPE/PKS were investigated. Rheological study of the biocomposites was carried out by means of capillary rheometer under temperature of 190 °C, 200 °C and 210 °C. Thermal properties of biocomposites were studied by using thermo gravimetric analysis (TGA). The rheological results showed that the flowability of the composite increased with increasing temperature. Meanwhile, the result of TGA showed that at higher PKS loading, rHDPE/PKS biocomposites had lower total weight loss. The thermal stability of the biocomposites was reduced due to the addition of filler loading.

Study on the thermal stability of Controlled Permeability Formwork

2011 ◽  
Vol 374-377 ◽  
pp. 1426-1429
Author(s):  
Xiao Meng Guo ◽  
Jian Qiang Li ◽  
Xian Sen Zeng ◽  
De Dao Hong
Keyword(s):  
Thermal Stability ◽  
Thermal Properties ◽  
Dynamic Mechanical Analysis ◽  
Thermo Gravimetric Analysis ◽  
Mechanical Analysis ◽  
Gravimetric Analysis ◽  
Construction Work ◽  
Thermo Gravimetric ◽  
Excellent Thermal Stability ◽  
Thermal Stability Of

In this study, the thermal properties of a kind of new geotextile materials, so called controlled permeable formwork (CPF), were studied. Thermo-gravimetric analysis showed that the weight of CPF didn’t change much between 0~350 °C. Dynamic mechanical analysis showed that the storage modulus of CPF reduced from 25 MPa to around 10 MPa when the temperature rose to above 100 °C. The strength of sample decreased slightly with the increase of the temperature. The breaking elongation changed slightly with a maximum at 80 °C. The CPF showed excellent thermal stability and was suitable for general use in construction work.

scholarly journals In situ polymerization of polypyrrole on cotton fabrics as flexible electrothermal materials

2019 ◽  
Vol 14 ◽  
pp. 155892501982744 ◽  
Author(s):  
Juan Xie ◽  
Wei Pan ◽  
Zheng Guo ◽  
Shan Shan Jiao ◽  
Ling Ping Yang
Keyword(s):  
Thermal Stability ◽  
Tensile Strength ◽  
In Situ Polymerization ◽  
Thermo Gravimetric Analysis ◽  
Cotton Fabrics ◽  
Morphological Properties ◽  
Polymerization Process ◽  
Maximum Temperature ◽  
Gravimetric Analysis

Polypyrrole/cotton composites have substantial application potential in flexible heating devices due to their flexibility, high conductivity, and thermal stability. In this context, a series of flexible polypyrrole/cotton fabrics were intrinsically prepared using in situ polymerization process with the different Py/FeCl3 concentration ratios. To investigate their structural and morphological properties, thermal stability, tensile strength, conductivity, and heat-generating property, the composite fabrics were subjected to Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, thermo-gravimetric analysis, mechanical properties, and resistivity measurements. The results showed that polypyrrole/cotton fabrics exhibited a low resistivity of 0.37 Ω cm. Temperature–time curve showed that temperature of the polypyrrole/cotton fabrics increased very quickly from room temperature to a steady-state maximum temperature of 168.3°C within 3 min at applied voltage of 5 V. Tensile strength of polypyrrole/cotton composites reached to 58 MPa, which far surpassed raw cotton fabrics. Therefore, polypyrrole/cotton fabrics have exhibited high electrical, thermal properties, and mechanical strength, which can be utilized as an ideal flexible heating element.

Role of Anionic Chromium Species in Leather Tanning

2021 ◽  
Vol 116 (10) ◽  
Author(s):  
Abhinandan Kumar ◽  
Jaya Prakash Alla ◽  
Deepika Arathanaikotti ◽  
Ashok Raj J. ◽  
Chandrababu N. K.
Keyword(s):  
Thermal Stability ◽  
Organic Acid ◽  
Organoleptic Properties ◽  
Chromium Species ◽  
Shrinkage Temperature ◽  
Leather Processing ◽  
Chrome Tanning ◽  
Anionic Species ◽  
Reactive Mechanism

Chrome tanned leathers are definitely unique in comparison with leather made from any other known tanning agents, especially in terms of thermal stability, cost and its reactive mechanism with collagen fibers. In our current studies, self basifying chrome tanning materials masked with different percentages of organic acid were prepared and applied after the de-liming stage of leather processing. This eliminated the need for pickling and basification steps. Tanned leathers resisted shrinkage up to 103 and 105±2°C while conventional chrome tanned leathers resisted up to 108±2°C. Also, interaction of anionic chrome species in tanning was studied. It was observed that the percentage of anionic species in the experimental chrome tanning material was higher than conventional chrome tanning material and the shrinkage temperature achieved by application of experimental tanning material proves that anionic species do involve in tanning. Tanned leathers were crusted and analysed for strength and organoleptic properties.

scholarly journals Structural Characterization and Digestibility of Curcumin Loaded Octenyl Succinic Nanoparticles

Nanomaterials ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 1073 ◽  
Author(s):  
Zhongshan Hu ◽  
Tao Feng ◽  
Xiaolan Zeng ◽  
Srinivas Janaswamy ◽  
Hui Wang ◽  
...  
Keyword(s):  
Self Assembly ◽  
Water Solubility ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
Starch Structure ◽  
Anti Cancer ◽  
Octenyl Succinic Anhydride ◽  
The Fourier Transform ◽  
Thermal Stability Of

Curcumin displays anti-cancer, anti-inflammatory and anti-obesity properties but its water insolubility limits the wholesome utility. In this study, curcumin has been encapsulated in an amphiphilic biopolymer to enhance its water solubility. This was accomplished through self-assembly of octenyl succinic anhydride–short glucan chains (OSA–SGC) and curcumin. The nanoparticles were prepared with the degree of substitution (DS) of 0.112, 0.286 and 0.342 of OSA. Thus prepared nanoparticles were in the range of 150–200 nm and display high encapsulation efficiency and high loading capacity of curcumin. The Fourier-transform infrared (FTIR) and X-ray diffraction analyses confirmed the curcumin loading in the OSA–SGC nanoparticles. The complexes possessed a V-type starch structure. The thermo gravimetric analysis (TGA) revealed the thermal stability of encapsulated curcumin. The OSA–SGC nanoparticles greatly improved the curcumin release and dissolution, and in-turn promoted the sustained release.

Polymer nanocomposites reinforced with C60 fullerene: effect of hydroxylation

2011 ◽  
Vol 45 (25) ◽  
pp. 2595-2601 ◽  
Author(s):  
Tsuyoshi Saotome ◽  
Ken Kokubo ◽  
Shogo Shirakawa ◽  
Takumi Oshima ◽  
H. Thomas Hahn
Keyword(s):  
Thermal Stability ◽  
Thermo Gravimetric Analysis ◽  
Nanocomposite Films ◽  
Light Transmittance ◽  
C60 Fullerene ◽  
Partial Hydrolysis ◽  
Poly Vinyl Alcohol ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Thermal Stability Of

Novel nanocomposite films of polycarbonate (PC) with fullerene derivatives, such as pristine fullerene C60 and polyhydroxylated-fullerenes, C60(OH)12 and C60(OH)36, were prepared. The optical, thermal, and mechanical properties of the composites were measured. Nanocomposite films of poly (vinyl alcohol) (PVA) with C60(OH)36 were prepared as a reference to show how improved dispersion of the nanofiller affects the overall transparency of the composites. Ultraviolet-visible spectroscopy showed that the addition of hydroxylated fullerenes did not affect visible light transmittance of the films significantly in the range of 400–800 nm. Differential scanning calorimetry (DSC) and thermo–gravimetric analysis (TGA) measurements showed the increased thermal stability of PC/C60(OH)12 film as compared to pristine PC film. This phenomenon was explained by the rigid polymer interphase regions formed around C60(OH)12 due to the plausible hydrogen bonding and hydrophobic interaction. On the other hand, the lower thermal stability of PC–C60(OH)36 was assumed to be caused by large agglomeration of the C60(OH)36 particles and the partial hydrolysis of the polycarbonate matrix. Tensile testing of the composites showed reduction in elongation at break and yield tensile strength. These results may be caused by the particle agglomerations which act as the initiation points for cracks.

Liquid-State Synthesis and Properties of Fluorescent Conducting Polymers: α, βi-SiW11AlIII/Polyaniline

2013 ◽  
Vol 561 ◽  
pp. 13-18
Author(s):  
Wan Li Yang ◽  
Qing Wen Wang ◽  
Rong Hua Ma
Keyword(s):  
Thermal Stability ◽  
Ir Spectroscopy ◽  
Fluorescence Spectroscopy ◽  
Hybrid Materials ◽  
Liquid State ◽  
Thermo Gravimetric Analysis ◽  
Synthesis Method ◽  
Average Diameter ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric

Four polyaniline hybrid materials were prepared by liquid-state synthesis method in the presence of dopant which synthesized by transition metal mono-substituted Keggin structure silicotungstate anions α, βi-[SiW11Al (H2O)O39]4-.The polyaniline hybrid materials were characterized by elemental analysis, IR spectroscopy, fluorescence spectroscopy, scanning electeon microscopy (SEM) and thermo gravimetric analysis, the properties of which such as thermal stability and conducting behavior were studied. It proved that the average diameter was 100nm, the conductivity was 9×10-2s·cm-1 and the flourescence property was better.

Effect of heat treatment on the mechanical properties of jute yarns

2021 ◽  
pp. 002199832199910
Author(s):  
Y Ben Smail ◽  
A El Moumen ◽  
A Imad ◽  
F Lmai ◽  
M Ezahri
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Low Cost ◽  
Thermo Gravimetric Analysis ◽  
Natural Fibers ◽  
Young Modulus ◽  
Effect Of Temperature ◽  
Gravimetric Analysis ◽  
Jute Fibers ◽  
Different Temperatures

In the last two decades, an increasing interest has been observed for the use of natural fibers such as jute fibers in different applications. These fibers are characterized by their low cost and their availability. They are mainly used in fabric bag manufacturing. The objective of this paper is to study the effect of temperature on the mechanical properties of jute yarns. An experimental study was conducted at different temperatures (22 °C; 80 °C; 105 °C and 150 °C) for 24 h. Each degree was followed by tensile testing of the specimen. Besides, the thermo-gravimetric analysis (TGA) was used to investigate the effect of the temperature on the thermal stability and the thermal degradation of the jute fibers. In addition, the statistical analysis was performed using the method of two and three-parameter Weibull distribution to determine the spatial distribution of the properties. The results showed that there was a degradation of the mechanical properties of the jute yarns heated to high temperature compared to the raw yarns (considered as a specimen exposed to 22 °C). The tensile strain and the Young modulus failed by 36% and 13% respectively for the specimens heated at 150 °C and the failure kinematic of the jute fiber was affected by the temperature of heating. The TGA showed that the thermal stability of the jute yarns was affected by two factors: fibers drying and their changing temperatures.

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