scholarly journals Effects of Adding Antioxidants on the Lightfastness Improvement of Refined Oriental Lacquer

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1110
Author(s):  
Kun-Tsung Lu ◽  
Jia-Jhen Lee
Keyword(s):  
Color Difference ◽  
Film Properties ◽  
Drying Time ◽  
Photo Degradation ◽  
Photo Oxidation ◽  
High Durability ◽  
Brightness Difference ◽  
Bending Resistance ◽  
Main Component ◽  
Oriental Lacquer

Refined oriental lacquer (ROL) is a natural polymeric material with a satiny texture, elegant beauty, and high durability for wood furniture and handicraft finishing. However, its poor lightfastness, which results from the photo-degradation or photo-oxidation of its main component, catechol derivatives, must be improved for its widespread utilization. In this study, two experiments were performed. First, five types of antioxidants, including three primary antioxidants, such as 2,2′-methylenebis(6-nonyl-p-cresol) (coded as AO-1), 2,2′-methylenebis(6-tert-butyl-4-methylphenol) (AO-2), and bis [4-(2-phenyl-2-propyl) phenyl] amine (AO-N), and two secondary antioxidants, such as tris (2,4-ditert-butylphenyl) phosphite (AO-P) and dilauryl thiodipropionate (AO-S), were investigated to determine which is the most effective for improving the lightfastness of ROL. Secondly, the appropriate quantity of the best antioxidant, including 0, 1, 2, 3, 5, and 10 phr, was also determined. The lightfastness parameters, such as brightness difference (ΔL*), yellowness difference (ΔYI), and color difference (ΔE*), as well as other coating and film properties, were assessed. The results showed that the primary antioxidants had higher efficiency than secondary antioxidants for improving the lightfastness of ROL. Among the primary antioxidants, the 5 phr AO-N was the most effective at improving the lightfastness of ROL; however, 1 phr addition had already shown significantly improved efficiency. In addition, the drying time of ROL was extended and film properties decreased when increasing the content of AO-N, but the 1-phr-containing ROL displayed superior film properties, especially adhesion and bending resistance, compared with the raw ROL film.

scholarly journals The Effects of Adding Heartwood Extractives from Acacia confusa on the Lightfastness Improvement of Refined Oriental Lacquer

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4085
Author(s):  
Chia-Wei Chang ◽  
Jia-Jhen Lee ◽  
Kun-Tsung Lu
Keyword(s):  
Color Difference ◽  
Uv Exposure ◽  
Total Phenolic ◽  
Ftir Analysis ◽  
Phenolic Contents ◽  
Acacia Confusa ◽  
Brightness Difference ◽  
Suitable Amount ◽  
Heartwood Extractives ◽  
Oriental Lacquer

In this study, a renewable polymeric material, refined oriental lacquer (ROL), used as a wood protective coating, and the Acacia confusa Merr. heartwood extractive, which was added as a natural photostabilizer for improving the lightfastness of ROL, were investigated. The best extract conditions for preparing heartwood extractives and the most suitable amount of addition (0, 1, 3, 5, and 10 phr) were investigated. The lightfastness index including brightness difference (ΔL *), yellowness difference (ΔYI), and color difference (ΔE *), and their applied properties of coating and film were measured. In the manufacture of heartwood extractives, the yield of extractives with acetone solvent was 9.2%, which was higher than that from toluene/ethanol solvent of 2.6%, and also had the most abundant total phenolic contents (535.2 mgGAE/g) and total flavonoid contents (252.3 μgRE/g). According to the SEM inspection and FTIR analysis, the plant gums migration to the surface of films and cracks occurred after UV exposure. The phenomena for photodegradation of ROL films were reduced after the addition of heartwood extractives. Among the different amounts of the heartwood extractives, the 10 phr addition was the best choice; however, the 1 phr heartwood extractive addition already showed noticeable lightfastness improvement. The drying times of ROL were extended and film performances worse with higher additions of heartwood extractives. Among the ROL films with different heartwood extractive additions, the ROL film with 1 phr addition had superior films properties, regarding adhesion and thermal stability, compared with the films of raw oriental lacquer.

scholarly journals The Effects of Adding Different HALS on the Curing Process, Film Properties and Lightfastness of Refined Oriental Lacquer

Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 990
Author(s):  
Chia-Wei Chang ◽  
Jia-Jhen Lee ◽  
Kun-Tsung Lu
Keyword(s):  
Ph Value ◽  
Oxidative Polymerization ◽  
Radical Scavenging ◽  
Polymeric Coating ◽  
Film Property ◽  
Film Properties ◽  
Drying Time ◽  
Outdoor Application ◽  
Radical Scavenging Ability ◽  
Oriental Lacquer

Oriental lacquer is a natural polymeric coating with a satiny texture and excellent characteristics, such as chemical resistance and durability. However, the poor lightfastness resulted in the natural aromatic structures of the urushiol structures limited its suitability for outdoor application. This study aimed at the improvement of the lightfastness by adding the different hindered amine light stafbilizers (HALS) with 2 phr addition as well as the effects on the coating and film property of the refined oriental lacquers (RL). The Cryptomeria japonica plate, glass sheets, and the other substrates were used for finishing. The results showed that the lightfastness of RL film was obviously improved by adding 2 phr HALS of Bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (H90) containing -NH group and Bis (1,2,2,6,6-pentamethyl-4-piperidinyl)-[[3,5-bis(1,1-dimethyl ethyl) -4-hydroxyphenyl] methyl] butylmalonate (H60) containing -NCH3 groups. The HALS additions increased the pH value of RL and improved the activities of laccase-catalyzed reaction. Meanwhile, the oxidative polymerization of the side chains of RL was inhibited, caused by a radical scavenging ability of HALS. The changes in the drying process affected not only the curing time, but also the film properties. Among the 2 phr additions of different HALS, the film containing H90 had the best lightfastness. Meanwhile, it kept the most similar properties with RL and shortened the drying time of RL, and it was selected as the best HALS addition under 2 phr in this study.

scholarly journals Manufacture and Characteristics of Oil-Modified Refined Lacquer for Wood Coatings

Coatings ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 11 ◽  
Author(s):  
Chia-Wei Chang ◽  
Hsiu-Ling Lee ◽  
Kun-Tsung Lu
Keyword(s):  
Linseed Oil ◽  
Impact Resistance ◽  
Polymeric Coating ◽  
Drying Time ◽  
Nitrogenous Compounds ◽  
Drying Oils ◽  
Practical Applications ◽  
Wood Coatings ◽  
Bending Resistance ◽  
Oriental Lacquer

Oriental lacquer, a natural and renewable polymeric coating, comes from the sap produced by lacquer trees. For practical applications, oriental lacquer must be refined to reduce its water content and enhance its quality. In this study, drying oils were blended with oriental lacquer during a refining process to produce oil-modified refined lacquer (OMRL). Rhus succedanea lacquer, composed of 54.1% urushiols, 34.3% water, 7.2% plant gum, and 4.4% nitrogenous compounds, and drying oils, including tung oil (TO), linseed oil (LO), and dehydrated castor oil (DCO), were used as materials in this study. The effect of type and amount (0%, 10%, and 20% by wt %) of drying oils added to lacquer on lacquer properties were evaluated. Results show that the drying oils acted as a diluent, which reduced the viscosity, and enhanced workability, shortened touch-free drying time and accelerated the hardened drying of the OMRL. The results also indicated that the hardness, mass retention, Tg, tensile strength, abrasion resistance, and lightfastness of OMRL films decreased as more drying oils were blended with lacquer. Conversely, the bending resistance, elongation at break, impact resistance increased. Gloss was greatly improved through the blending of more drying oils with lacquer. In conclusion, the LO-modified refined lacquer (RL) had the highest film gloss and the DCO-modified RL had the shortest drying time for coating. Otherwise, the film properties were similar among the three types of drying oils.

scholarly journals Optimization and Prediction of the Drying and Quality of Turnip Slices by Convective-Infrared Dryer under Various Pretreatments by RSM and ANFIS Methods

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 284
Author(s):  
Ebrahim Taghinezhad ◽  
Mohammad Kaveh ◽  
Antoni Szumny
Keyword(s):  
Energy Efficiency ◽  
Color Difference ◽  
Moisture Diffusivity ◽  
Effective Moisture Diffusivity ◽  
Diffusivity Coefficient ◽  
Drying Process ◽  
Anfis Model ◽  
Drying Time ◽  
Effective Moisture ◽  
Response Variables

Drying can prolong the shelf life of a product by reducing microbial activities while facilitating its transportation and storage by decreasing the product weight and volume. The quality factors of the drying process are among the important issues in the drying of food and agricultural products. In this study, the effects of several independent variables such as the temperature of the drying air (50, 60, and 70 °C) and the thickness of the samples (2, 4, and 6 mm) were studied on the response variables including the quality indices (color difference and shrinkage) and drying factors (drying time, effective moisture diffusivity coefficient, specific energy consumption (SEC), energy efficiency and dryer efficiency) of the turnip slices dried by a hybrid convective-infrared (HCIR) dryer. Before drying, the samples were treated by three pretreatments: microwave (360 W for 2.5 min), ultrasonic (at 30 °C for 10 min) and blanching (at 90 °C for 2 min). The statistical analyses of the data and optimization of the drying process were achieved by the response surface method (RSM) and the response variables were predicted by the adaptive neuro-fuzzy inference system (ANFIS) model. The results indicated that an increase in the dryer temperature and a decline in the thickness of the sample can enhance the evaporation rate of the samples which will decrease the drying time (40–20 min), SEC (from 168.98 to 21.57 MJ/kg), color difference (from 50.59 to 15.38) and shrinkage (from 67.84% to 24.28%) while increasing the effective moisture diffusivity coefficient (from 1.007 × 10−9 to 8.11 × 10−9 m2/s), energy efficiency (from 0.89% to 15.23%) and dryer efficiency (from 2.11% to 21.2%). Compared to ultrasonic and blanching, microwave pretreatment increased the energy and drying efficiency; while the variations in the color and shrinkage were the lowest in the ultrasonic pretreatment. The optimal condition involved the temperature of 70 °C and sample thickness of 2 mm with the desirability above 0.89. The ANFIS model also managed to predict the response variables with R2 > 0.96.

scholarly journals Dyeing of Polyester with Reactive Dyestuffs Using Nano-Chitosan

2018 ◽  
Vol 13 (2) ◽  
pp. 155892501801300
Author(s):  
Neda Najafzadeh ◽  
Sima Habibi ◽  
Mohammadreza A. Ghasri
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Surface Morphology ◽  
Reactive Dyes ◽  
Color Difference ◽  
Polyester Fabric ◽  
Surface Chemical ◽  
Bending Resistance ◽  
Bending Behavior ◽  
Scanning Electron

The main objective of this work is to investigate the effect of nano-chitosan on the dyeing of polyester fabric with reactive dyes. Polyester fabric was treated with alkali and coated with nano-chitosan. Afterwards all samples were dyed with reactive dyes. The water absorption and bending resistance of pristine polyester, alkaline and chitosan-treated polyester were measured. In order to investigate surface chemical bonding, FTIR/ATR was employed. Surface morphology of fabrics was observed using scanning electron microscopy (SEM). Wettability and bending behavior of the treated polyester increased compared to the untreated one. The color difference between the dyed blank and chitosan-treated samples was estimated using a spectrophotometer. The data obtained shows it is possible to use reactive dyes to dye polyester fabrics finished with nano-chitosan and the resulting fabrics will exhibit acceptable washing and rubbing fastness.

scholarly journals Manufacture and Characteristics of Oil-Modified Refined Lacquer for Wood Coatings

2018 ◽  
Author(s):  
Chia-Wei Chang ◽  
Hsiu-Ling Lee ◽  
Kun-Tsung Lu
Keyword(s):  
Linseed Oil ◽  
Impact Resistance ◽  
Polymeric Coating ◽  
Drying Time ◽  
Nitrogenous Compounds ◽  
Drying Oils ◽  
Drying Oil ◽  
Wood Coatings ◽  
Speed Up ◽  
Oriental Lacquer

Oriental lacquer, a natural and renewable polymeric coating, comes from the sap produced by lacquer trees. For practical application, oriental lacquer must be refined to reduce excess water and enhance its quality. In this study, drying oils were blended with oriental lacquer during the refining process to prepare an oil-modified refined lacquer (OMRL). The type and adding amount (0, 10, and 20% by wt.) of drying oils for wood coatings utilization were evaluated. Rhus succedanea oriental lacquer is composed of 54.1% urushiols, 34.3% water, 7.2% plant gum, and 4.4% nitrogenous compounds, and drying oils, including tung oil (TO), linseed oil (LO), and dehydrated castor oil (DCO) were used as materials in this study. The results show that the drying oil acts as a diluent, which reduces the viscosity and enhances the workability and could shorten the touch-free drying time and speed up the hardened drying of the OMRL. The results also indicate that the hardness, mass retention, Tg, tensile strength, abrasion resistance, and lightfastness of OMRL films decrease as more drying oils are blended. Conversely, the bending resistance, elongation at break, impact resistance increase, and particularly, the gloss, is greatly improved through the blending of more drying oils. In conclusion, the LO-modified refined lacquer (RL) has the highest film gloss and the DCO-modified RL has the shortest drying time for coating; otherwise, the film properties are similar among the three types of drying oil.

Osmotic Dehydration of Tomato Assisted by Ultrasound: Evaluation of the Liquid Media on Mass Transfer and Product Quality

2015 ◽  
Vol 11 (4) ◽  
pp. 505-516 ◽  
Author(s):  
Jefferson L. G. Corrêa ◽  
Ariana Justus ◽  
Letícia F. de Oliveira ◽  
Guilherme E. Alves
Keyword(s):  
Mass Transfer ◽  
Osmotic Dehydration ◽  
Color Difference ◽  
Distilled Water ◽  
Liquid Media ◽  
Drying Time ◽  
Solid Gain ◽  
Ultrasound Evaluation ◽  
The Media ◽  
Osmotic Agents

Abstract The treatment of a food in liquid media involves mass transfer and could aid to preserve some food properties. The assistance of ultrasound (US) could even improve the process. Therefore, the aim of this study was to evaluate US (frequency 25 kHz, powder intensity 8 kW m–3) in tomato treatment in sucrose and NaCl solutions, common osmotic agents. Moreover, for testing the influence of the media, distilled water and maltodextrin solution completed the set of tested liquids. Water loss (WL), solid gain (SG), water activity (aw), color parameters, like the total color difference (ΔE) and microstructure were evaluated. The advantages of NaCl and sucrose solutions were the high WL and SG values besides low aw and ΔE. The alterations in the microstructure of US-treated samples in distilled water or maltodextrin suggested that a product with low solid incorporation and reduced drying time could be obtained in a further drying.

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