Accelerated Ageing of Parchment: Investigation of a Photo Catalysed, Low-Heat Approach

2018 ◽  
Vol 39 (1) ◽  
pp. 33-70 ◽  
Author(s):  
Marie Sarah Kern ◽  
Andrea Pataki-Hundt ◽  
Jan Wouters ◽  
Daniel P. Kirby
Keyword(s):  
Moisture Absorption ◽  
Thermal Ageing ◽  
Absorption Capacity ◽  
Accelerated Ageing ◽  
Heat Sensitivity ◽  
Shrinkage Temperature ◽  
Art And Design ◽  
Bovine Hide ◽  
Ma Thesis ◽  
Structural Levels

Abstract Accelerated ageing is an often-used tool in conservation research, yet difficult to apply to parchment due to the materials inherent heat sensitivity. The complexity of this organic material makes the analysis of its deterioration especially challenging. An attempt to develop a non-heat ageing protocol for parchment is described in this paper. The work was performed within the scope of a MA-thesis at the State Academy of Art and Design Stuttgart. Samples of a modern new limed goat parchment and pieces of reconstituted parchment made from bovine hide powder were subjected to a combination of light ageing and dynamic ageing at moderate temperatures. All samples were analysed with the goal to observe degradation on as many structural levels as possible: colour measurement via VIS spectrometry and light-microscopic observation of fibre damage were employed to assess visible changes. Shrinkage temperature (Ts) was measured as an indicator for the amount of intact intrafibrillar bonds and the determination of the maximum moisture absorption capacity gave an impression on the parchments overall level of hygroscopy. In addition, PMF (Peptid Mass Fingerprinting) via MALDI/MS TOF was performed on extracts from unaged and light aged goat parchment. The results of the different types of analysis showed significant degradation on different structural levels of the parchment, indicating that accelerated ageing of parchment that uses a combination of light and dynamic ageing may be a viable alternative to the more commonly applied thermal ageing.

METHOD OF PROCESSING COLLAGEN FRESHWATER FISH TO OBTAIN A MATERIAL WITH A HIGH MOISTURE ABSORBING ABILITY

2019 ◽  
Author(s):  
Л.В. АНТИПОВА ◽  
С.А. ТИТОВ ◽  
И.В. СУХОВ
Keyword(s):  
Freshwater Fish ◽  
Moisture Absorption ◽  
Raw Materials ◽  
Silver Carp ◽  
Absorption Capacity ◽  
Personal Hygiene ◽  
Test Material ◽  
Free Access ◽  
High Moisture ◽  
Scanning Calorimetry

Исследовано взаимодействие коллагена пресноводных рыб с водой для повышения его водопоглощающей способности. Объектом исследования был вторичный продукт переработки рыбного сырья – шкуры прудовых рыб, преимущественно толстолобика. Для исследования были использованы методы термогравиметрии и дифференциальной сканирующей калориметрии. Измерения проведены на приборе синхронного термического анализа модели STA 449 F3 Jupiter. Установлено, что основная доля влаги связывается адсорбционным или осмотическим путем, а на долю капиллярной влаги приходится всего 7% массы воды, связанной образцами. Большая величина энергии связи адсорбции – 4 Дж/моль свидетельствует о способности функциональных групп коллагена к созданию гидратной оболочки, содержащей значительное количество воды. Для увеличения влагопоглощающей способности необходимо разрыхление коллагеновых волокон, что увеличивается свободный доступ влаги к фибриллам белка, увеличивающим впитывание влаги. Для эффективного разрыхления предложено выдерживать шкуры толстолобика в растворе органических кислот концентрацией 0,5%. Это позволяет добиться высокой влагоемкости, которая достигает 35–40 объемов влаги на 1 единицу массы исследуемого материала, что делает перспективным использование коллагена в качестве материала для впитывающих влагу слоев средств личной гигиены, одежды, обуви. The interaction of freshwater fish collagen with water to increase its water absorption capacity was studied. The secondary product of processing of fish raw materials – skins of pond fish, mainly silver carp, was the object of study. Methods of thermogravimetry and differential scanning calorimetry were used for the study. Measurements were carried out on the device of synchronous thermal analysis of model STA 449 F3 Jupiter. It was found that the bulk of the moisture is bound by adsorption or osmotic way, and 7% of mass of the water connected by samples fall to the share of capillary moisture. A large amount of adsorption binding energy – 4 J/mol indicates the ability of collagen functional groups to create a hydrated shell containing a significant amount of water. Loosening of collagen fibers is necessary to increase the moisture absorption capacity, which will increase the free access of moisture to the protein fibrils, increasing the absorption of moisture. It is proposed to withstand the skins of silver carp in a solution of organic acids with a concentration of 0,5% for effective loosening. This makes it possible to achieve high moisture capacity, which reaches 35–40 volumes of moisture per 1 unit mass of the test material, which makes it promising to use collagen as a material for moisture-absorbing layers of personal hygiene products, clothing, and shoes.

scholarly journals Effect of a Superabsorbent for the Improvement of Car Seat Thermal Comfort

2017 ◽  
Vol 25 (0) ◽  
pp. 83-87
Author(s):  
Funda Mazari ◽  
Adnan Mazari ◽  
Antonin Havelka ◽  
Jakub Wiener
Keyword(s):  
Thermal Comfort ◽  
Water Vapour ◽  
Polyurethane Foam ◽  
Sandwich Structure ◽  
Moisture Absorption ◽  
Absorption Capacity ◽  
High Moisture ◽  
Car Seats ◽  
Car Seat ◽  
Cover Material

The use of super absorbent polymers (SAP) for moisture absorption and comfort is still unexplored. The aim of this work was to observe the application of super absorbent fibres in car seats for comfort purposes. In this research the efficiency of different SAP fibrous webs were determined under different moisture percentages to examine the sorption and desorption efficiency. A SAP fibrous web with low thickness and high moisture absorption were tested with a multilayer sandwich structure of a car seat cover to determine moisture absorption through the cover material. The standard Cup method was used to determine the moisture permeability of different car seat covers with a superabsorbent layer closed with impermeable polyurethane foam. It was observed that the SAP fibrous layers are very effective in absorbing and desorbing water vapour under extremely high and low moisture percentages. In extreme humid conditions (95%RH), 20g of the SAP layer absorbs nearly 70% of its weight in water vapour, reaching the maximum absorption capacity in 6 hours.

scholarly journals Experimental Research on the Wettability of Recycled Aggregate Concrete with Fly Ash

2013 ◽  
Vol 7 (1) ◽  
pp. 232-236
Author(s):  
Yuanchen Guo ◽  
Xue Wang ◽  
Jueshi Qian
Keyword(s):  
Fly Ash ◽  
Moisture Absorption ◽  
Drying Shrinkage ◽  
Absorption Capacity ◽  
Recycled Aggregate Concrete ◽  
Recycled Aggregate ◽  
Structure Theory ◽  
Replacement Rate ◽  
Aggregate Concrete ◽  
Main Factors

Material adsorption, the reverse process of evaporation diffusion, directly reflects the wettability of materials. Wettability is one of the main factors that affect the drying shrinkage of materials. A device that measures the wettability of recycled aggregate concrete (RAC) with fly ash is proposed in this study based on pore structure theory. The isothermal absorption curve of RAC is examined with different fly ash contents. Results show that as the recycled aggregate replacement rate increases, the moisture absorption capacity of RAC gradually increases. The addition of fly ash improves the porosity of RAC structures and reduces material wettability.

Investigation of the thermal ageing process and mechanism of benzoxazine/bismaleimide/cyanate ester copolymer

2018 ◽  
Vol 31 (6) ◽  
pp. 623-630 ◽  
Author(s):  
Yiqun Wang ◽  
Shiyi Zhou ◽  
Haiying Du ◽  
Wentao Zhang
Keyword(s):  
Mechanical Properties ◽  
Elevated Temperatures ◽  
Moisture Absorption ◽  
Ageing Time ◽  
Engineering Application ◽  
Crosslinking Density ◽  
Thermal Ageing ◽  
Cyanate Ester ◽  
Frp Composites ◽  
Interior Stress

Fibre-reinforced polymer (FRP) composites with thermosetting resin matrices are widely used in civil engineering (e.g. pultruded FRP plates and bars), and their thermal ageing behaviour is a concern when they are subjected to elevated temperatures (e.g. FRP chimney). In the present article, the effects of thermal ageing at 200°C and 250°C in air for up to 1000 h on mechanical properties and mechanism of the benzoxazine (Boz), bisphenol A dicyanate cyanate ester (BADCy), and 4,4′-bismaleimidodiphenyl methane (BMI) have been investigated. The effect of time in thermal ageing on structural and mechanical properties of the Boz/BMI/BADCy resin was deeply studied. The moisture absorption increases linearly with the square root of ageing time and it follows Fick’s second law. There are two main categories of reactions in thermal ageing: the first one is the post-curing process, which leads to a larger crosslinking density and a reduced interior stress; while the other is the formation of microcracks and thermal oxidation at the surface of the Boz/BMI/BADCy resin. The combination of the above factors leads to an increase–decrease variation in the mechanical properties. This work is believed to benefit the wide and safe application of a certain Boz/BMI/BADCy resin system in engineering application.

scholarly journals Preparation and performance analysis of a coking coal dust suppressant spray

2021 ◽  
Author(s):  
Jiuhong Jiang ◽  
Pengfei Wang ◽  
Ye Pei ◽  
Ronghua Liu ◽  
Liming Liu ◽  
...  
Keyword(s):  
Reverse Osmosis ◽  
Moisture Absorption ◽  
Coal Dust ◽  
Sodium Dodecyl ◽  
Sodium Dodecyl Benzene Sulfonate ◽  
Absorption Capacity ◽  
Orthogonal Experimental Design ◽  
Coking Coal ◽  
Dodecyl Benzene Sulfonate ◽  
And Performance

Abstract Coking coal dust is extremely hydrophobic; therefore, combination with droplets in the air is difficult and dust suppression is challenging. Here, a dust suppressant spray for coking coal dust was studied in order to improve of the combination of droplets and coking coal dust. Based on monomer optimization and compounding analysis, two surfactant monomers, fatty alcohol ether sodium sulfate (AES) and sodium dodecyl benzene sulfonate (SDBS) were selected as the surfactant components of the dust suppressant. The surfactant monomers were combined with four inorganic salts and the reverse osmosis moisture absorption of each solution was determined. By combining the reverse osmosis moisture absorption values with the water retention experimental results, CaCl2 was identified as the optimal inorganic salt additive for the dust suppressant. Finally, the optimal concentration of each component was obtained using orthogonal experimental design i.e., AES (0.03%), SDBS (0.05%), and CaCl2 (0.4%). The dust suppressant solution formulated using this method had a high moisture absorption capacity and excellent performance. Graphic Abstract

Aspects of the Ageing of Elastomeric Materials

2017 ◽  
Vol 44 (12) ◽  
pp. 1-10 ◽  
Author(s):  
K. Oßwald ◽  
K. Reincke ◽  
S. Döhler ◽  
U. Heuert ◽  
B. Langer ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Viscoelastic Properties ◽  
Ageing Time ◽  
Absorption Capacity ◽  
Operating Conditions ◽  
Accelerated Ageing ◽  
Oxygen Absorption ◽  
Artificial Ageing ◽  
Direct Evaluation ◽  
Ageing Processes

Rising raw materials prices and increasing customer demands for reliability and durability mean that there is huge interest in finding more and more ways of improving the service life of elastomeric products, for economic and environmental reasons, by boosting their resistance under the relevant operating conditions. The material-dependent oxygen absorption capacity and oxygen permeability play an important role in oxidative ageing processes and their modelling. Thus, ageing resistance is substantially dependent on the rate of oxygen diffusion into the bulk of the material in the case of thermo-oxidative attack. To evaluate the resistance of materials to external influences, artificial ageing methods are used in practice. The advantage of these methods is that, as a result of intensifying the test parameters, e.g. temperature and humidity, the ageing processes in the vulcanisate are accelerated. Within the scope of this study, the influence of accelerated ageing on the mechanical and viscoelastic properties of mainly carbon-black-filled natural rubber (NR) vulcanisates was studied in an oxygen atmosphere at elevated temperature and in oxygen with solar radiation. The filler content was varied and the antioxidant IPPD was used. The analyses showed that, as well as mechanical properties such as hardness and tensile strength, the viscoelastic properties are also affected, depending on the ageing time and the type of ageing. In addition to the investigation of mechanical properties, a direct evaluation of the material change was carried out for selected samples by means of analytical tests. The investigations showed the deterioration of the antioxidant activity.

scholarly journals Electrophoretic Deposition of Chitosan Films Doped with Nd2Ti2O7 Nanoparticles as Protective Coatings against Corrosion in Saline Solutions

2019 ◽  
Vol 2019 ◽  
pp. 1-17 ◽  
Author(s):  
M. Martinez-Gomez ◽  
A. Quinto-Hernandez ◽  
N. S. Flores-Garcia ◽  
Jan Mayén ◽  
M. Dominguez-Diaz ◽  
...  
Keyword(s):  
Electrophoretic Deposition ◽  
Moisture Absorption ◽  
Protective Coatings ◽  
Effective Area ◽  
Reduction Reaction ◽  
Absorption Capacity ◽  
X Ray Diffraction ◽  
Chitosan Films ◽  
Average Size ◽  
Saline Solutions

In this study, the electrophoretic deposition of chitosan films doped with Nd2Ti2O7 nanoparticles was carried out as corrosion protection systems for exposed materials in aqueous environments rich in chlorides. Completely crystalline Nd2Ti2O7 nanoparticles with an average size of 100-200 nm were obtained. Electrophoretic deposition of chitosan films with Nd2Ti2O7 nanoparticles was possible. With a working voltage of 5 V and 20 minutes of deposition, homogenous chitosan films with a thickness of 4 microns were obtained. According to the FT-IR (Fourier transform infrared spectroscopy), Raman, and XRD (X-ray diffraction) analyses, it was observed that the presence of the nanoparticles modified the properties of the chitosan films, that is, their crystallinity was increased and their moisture absorption capacity was reduced. These modifications caused a better performance against the corrosion of chitosan films deposited on 1018 carbon steel. Its electrochemical evaluation showed that the chitosan films perform as cathodic coatings by affecting the oxygen reduction reaction. This was possible due to the barrier effect of the Nd2Ti2O7 nanoparticles, by blocking the effective area for the diffusion of the aggressive electrolyte species.

Role of thermoxidation and depolymerisation in the ageing of systems paper/gum arabic/historical ink

2014 ◽  
Vol 68 (4) ◽  
Author(s):  
András Peller ◽  
Milena Reháková ◽  
Michaela Ciglanská ◽  
Peter Šimon
Keyword(s):  
Reaction Path ◽  
Gum Arabic ◽  
Thermal Ageing ◽  
Accelerated Ageing ◽  
Thermal Method ◽  
Reaction Paths ◽  
Thermal Methods ◽  
Iron Gall ◽  
A Minor ◽  
Whatman Paper

AbstractThe aim of this study was to assess the role and proportional representation of depolymerisation and thermoxidation reaction paths in the systems paper/gum arabic (GA)/historical ink during various accelerated ageing methods. The historical inks under study are iron-gall, bistre, and sepia. The results indicate that thermoxidation represents only a minor reaction path in the ageing of paper/GA/ink systems except for the iron-gall ink and the light-thermal method of accelerated ageing. The iron-gall ink accelerates both reaction paths of ageing, i.e. thermoxidation and depolymerisation; in this case, thermoxidation might become the prevailing degradation reaction path. For the sepia ink, an anti-depolymerisation stabilising effect in thermal methods of ageing has been detected. Considering the thermoxidation reaction path, the results even suggest that a compound preventing thermoxidation is formed during the thermally accelerated ageing in air and in 100 mg L−1 of NO2. In the light-thermal ageing, the most stable sample is the Whatman paper (W)/GA/bistre ink.

Investigation of wettability and moisture sorption property of electrospun poly(N-isopropylacrylamide) nanofibers

MRS Advances ◽  
2016 ◽  
Vol 1 (27) ◽  
pp. 1959-1964 ◽  
Author(s):  
Anupama Sargur Ranganath ◽  
V. Anand Ganesh ◽  
Kostiantyn Sopiha ◽  
Rahul Sahay ◽  
Avinash Baji
Keyword(s):  
Biomedical Applications ◽  
Elevated Temperatures ◽  
Moisture Absorption ◽  
Sorption Property ◽  
Moisture Sorption ◽  
Absorption Capacity ◽  
Electrospun Fibers ◽  
Water Harvesting ◽  
Water Contact ◽  
Hygroscopic Properties

ABSTRACTPoly(N-isopropylacrylamide) (PNIPAM) has been used extensively for numerous biomedical applications. However, there is not enough information in the literature on the wettability and hygroscopic properties of electrospun PNIPAM fibers, relevant for water harvesting applications. This study focuses on investigating the wettability and hygroscopic properties of electrospun PNIPAM fibers at room temperature and elevated temperature. The wettability properties of electrospun PNIPAM fibers were compared to spin-coated PNIPAM thin films. The wettability properties of the electrospun fibers were enhanced by 56% compared to spin-coated films. Water contact angle (WCA) measured on electrospun fibers was determined to be 137° at elevated temperatures while WCA on spin cast PNIPAM film was determined to be 81° at elevated temperatures. Furthermore, hygroscopic properties of the electrospun PNIPAM fibers were studied using thermogravimetric analysis (TGA). The PNIPAM fibers are seen to exhibit moisture absorption capacity of about 16.6 wt. % under humid conditions.

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