scholarly journals Synthesis of Bio-Oilphenol-Formaldehyde Resins under Alkali Conditions

2020 ◽  
Vol 71 (1) ◽  
pp. 19-27
Author(s):  
Günay Özbay ◽  
Caglar Cekic ◽  
Muhammad Syarhabil Ahmad ◽  
Erkan Sami Kokten
Keyword(s):  
Shear Strength ◽  
Phenol Formaldehyde ◽  
Bonding Performance ◽  
Performance Requirements ◽  
Vacuum Pyrolysis ◽  
Treatment Conditions ◽  
Bio Oil ◽  
Dry Conditions ◽  
Ft Ir ◽  
Pre Treatment

In the present study, bio-oil produced from vacuum pyrolysis of woody biomass has been investigated as a source of chemical feedstock. Bio-based resins were produced using the bio- oil with phenol substitutions ranging from 10 to 30 wt%. The conventional GC/MS analysis was carried out for the evaluation of the chemical composition of bio-oil. TGA, DSC and FT-IR analyses were used in order to characterize the bio-oil-phenol-formaldehyde (BPF) resins. The bonding quality of wood samples bonded with the BPF resins was investigated under different pre-treatment conditions. The highest shear strength was observed for the control samples bonded with the laboratory PF resin. As the amount of bio-oil was increased up to 30 wt%, the shear strength of the samples decreased from 12.08 to 11.76 N/mm2. The bonding performance was not negatively affected by the combination of bio-oil under dry conditions. According to TS EN 12765 standard, the relevant performance requirements for bonded samples under dry conditions must be at least 10 N/mm2. Relating to the standard, all samples bonded with BPF resins obtained the requirements for durability class C1. Under wet conditions, the bonding performance was negatively affected by the addition of bio-oil. However, the BPF resins fulfilled the durability requirements for C1, C2, and C3 specified in EN 12765 (2002).

scholarly journals TECHNOLOGICAL PROPERTIES OF PLYWOOD BONDED WITH PHENOL-FORMALDEHYDE RESOL RESIN SYNTHESIZED WITH BIO-OIL

CERNE ◽  
2017 ◽  
Vol 23 (4) ◽  
pp. 493-500 ◽  
Author(s):  
Nadir Ayrilmis ◽  
Günay Özbay
Keyword(s):  
Phenol Formaldehyde ◽  
Modulus Of Rupture ◽  
Synthesis Process ◽  
Molecular Weights ◽  
Vacuum Pyrolysis ◽  
Bio Oil ◽  
Resol Resin ◽  
Different Types ◽  
Wet Condition ◽  
Pine Wood Sawdust

ABSTRACT In this study, it was aimed to use of bio-oil as an alternative to petroleum-based phenol in the production of phenol-formaldehyde (PF) resin used for making exterior plywood.Bio-oil obtained from pine wood sawdust using a vacuum pyrolysis reactor at 500 °C. The PF resol resins were produced by substituting up to 20 wt% of phenol with bio-oil by modifying the chemical synthesis process. FT-IRanalysis was performed to characterizethe organic functional groups in the bio-oil modified PF resins. In comparison to the commercial and lab-made PF resins, the bio-oil modified PF resins were found to have larger average molecular weights, higher polydispersity indices, and shorter gel times. Six different types of plywood panels were produced from the experimental PF resins which were commercial PF resin, lab-made PF resin, and PF resins modified with bio oil of 5, 10, 15 or 20 wt% contents, respectively. Plywood specimens produced with the PF resin modified with bio-oil up to 20 wt% had better tensile shear strength (wet condition), modulus of rupture, and modulus of elasticity in bending as compared to the commercial and lab-made PF resins.

scholarly journals Radial variation in bonding performance of preservative-treated wood within Pinus elliottii trees and its relationships with wood density and adhesive penetration

BioResources ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. 2204-2214
Author(s):  
La Hu ◽  
Lizhe Qin ◽  
Dongshan Wu ◽  
Huilan Xu ◽  
Zhangqi Yang
Keyword(s):  
Shear Strength ◽  
Wood Density ◽  
Phenol Formaldehyde ◽  
Treated Wood ◽  
Correlation Coefficients ◽  
Pinus Elliottii ◽  
Wood Failure ◽  
Bonded Joints ◽  
Bonding Performance ◽  
Increasing Trends

Pinus elliottii wood from different radial locations within trees was used to prepare two-layer preservative-treated wood joints with alkaline copper quaternary preservative and emulsion polymer isocyanates (EPI) or resorcinol-phenol-formaldehyde (RPF) adhesives. The radial variations in shear strength and wood failure percentage were analyzed. Radial variations in wood density and average penetration depth (AP) of adhesives were investigated to establish relationships between shear strengths and characteristics of bonded joints. The shear strengths of EPI- and RPF-bonded joints showed similar increasing trends from pith to bark, and they varied in ranges of 2.92 to 8.13 MPa and 2.03 to 7.12 MPa, respectively. The wood failure percentage of EPI joints (93% to 100%) had no significant differences in all the radial locations, but that of RPF joints (60% to 100%) showed a clear decreasing trend from pith to bark. High positive linear correlations were found between the shear strengths and wood density, and Pearson’s correlation coefficients for EPI and RPF were 0.934 (p < 0.01) and 0.931 (p < 0.01), respectively. Wood density is a very important factor influencing radial variations of bonding strengths. The correlation between the AP and shear strength was not significant at the 0.05 level.

Preparation of highly phenol substituted bio-oil-phenol-formaldehyde adhesives with enhanced bonding performance using furfural as crosslinking agent

2018 ◽  
Vol 136 (4) ◽  
pp. 46995 ◽  
Author(s):  
Yanyan Cheng ◽  
Guanghui Sui ◽  
Huan Liu ◽  
Xiaofeng Wang ◽  
Xiaomin Yang ◽  
...  
Keyword(s):  
Phenol Formaldehyde ◽  
Crosslinking Agent ◽  
Bonding Performance ◽  
Bio Oil

scholarly journals Exogenous 5-azaCitidine accelerates flowering and external GA3 increases ornamental value in Iranian Anemone accessions

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vahideh Yari ◽  
Zeynab Roein ◽  
Atefeh Sabouri
Keyword(s):  
Morphological Characteristics ◽  
Flower Longevity ◽  
Cut Flowers ◽  
Stem Height ◽  
Flowering Stage ◽  
Potted Plants ◽  
Dormancy Period ◽  
Treatment Conditions ◽  
Number Of Leaves ◽  
Pre Treatment

AbstractThe Anemone genus is a tuberous geophyte which undergoes a dormancy period during unfavorable environmental conditions for growth. Five species of the Anemone genus naturally grow in several regions of Iran. The diverse uses of Anemone in gardens for landscaping, cut flowers, and potted plants indicate its high ornamental potential. Its dormancy and flowering are influenced by various factors. The present paper was conducted to explore the flowering behavior of Anemone accessions in response to different pre-treatments. For this purpose, tubers of 18 Anemone accessions (A. coronaria and A. biflora) were collected from natural regions of six provinces in Iran. These tubers were subjected to different conditions of non-chilling (20 °C, 90 days), chilling (4 °C, 90 days), GA3 (150 mgL-1; 24 h), and 5-azaCitidine (5-azaC; 40 µM; 24 h) prior to the cultivation. Most of the accessions were able to enter the flowering stage without chilling. The shortest period for the sprouting of tubers (16.89 ± 7.83 days) belonged to 5-azaC pre-treatment. In addition, this treatment accelerated the flowering time (about 30 days earlier) and diameter of the stem, bud, and flower. Morphological characteristics, such as stem height, number of leaves, bud, and petal and the longevity of flowers on the plant were significantly affected by GA3 pre-treatment. Our results indicated a positive correlation between flower length, stem height, and stem diameter with flower longevity under different pre-treatment conditions. The present study demonstrated that accessions Anm3, Anm12, and Anm18 had ornamental values higher than the population mean across four conditions.

scholarly journals Selective Separation of Chalcopyrite from Galena Using a Green Reagent Scheme

Minerals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 796
Author(s):  
Kaile Zhao ◽  
Chao Ma ◽  
Guohua Gu ◽  
Zhiyong Gao
Keyword(s):  
High Selectivity ◽  
Sodium Sulfite ◽  
Ph Control ◽  
Industrial Applications ◽  
Environmental Risks ◽  
Theoretical Research ◽  
Depression Effect ◽  
Carboxymethyl Cellulose Sodium ◽  
Ft Ir ◽  
Pre Treatment

The study of the depression effect of non-toxic depressants on the flotation separation of chalcopyrite from galena is of great importance for both industrial applications and theoretical research. The mixed depressant (DFinal) of four common inhibitors—sodium carboxymethyl cellulose, sodium silicate, sodium sulfite, and zinc sulfate—exhibited high selectivity during the separation of chalcopyrite from galena. Flotation tests on an industrial copper–lead bulk concentrate showed that using this depressant mixture can achieve highly efficient separation of chalcopyrite from galena at the natural pH of the pulp. Copper and lead concentrates were produced at grades of 21.88% (Cu) and 75.53% (Pb), with recoveries of 89.07% (Cu) and 98.26% (Pb). This showed a similar performance of DFinal with dichromate, which is a depressant that is widely used in industry, but without the environmental risks or the need for pH control. Zeta potential and Fourier transform infrared (FT-IR) results showed that interaction between the surface of the chalcopyrite and the mixed depressant was prevented by pre-treatment with a composite thiophosphate collector (CSU11), while the mixed depressant could expel/replace the composite thiophosphate on the surface of galena by chemical adsorption, depressing its flotation. This is the reason why this non-toxic depressant achieved the selective depression of galena from chalcopyrite, leading to efficient flotation separation.

scholarly journals Effects of water absorption on the mechanical properties of hybrid natural fibre/phenol formaldehyde composites

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sekar Sanjeevi ◽  
Vigneshwaran Shanmugam ◽  
Suresh Kumar ◽  
Velmurugan Ganesan ◽  
Gabriel Sas ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Impact Strength ◽  
Water Absorption ◽  
Hybrid Composites ◽  
Phenol Formaldehyde ◽  
Natural Fibre ◽  
The Other ◽  
Fibre Reinforcement ◽  
Dry Conditions

AbstractThis investigation is carried out to understand the effects of water absorption on the mechanical properties of hybrid phenol formaldehyde (PF) composite fabricated with Areca Fine Fibres (AFFs) and Calotropis Gigantea Fibre (CGF). Hybrid CGF/AFF/PF composites were manufactured using the hand layup technique at varying weight percentages of fibre reinforcement (25, 35 and 45%). Hybrid composite having 35 wt.% showed better mechanical properties (tensile strength ca. 59 MPa, flexural strength ca. 73 MPa and impact strength 1.43 kJ/m2) under wet and dry conditions as compared to the other hybrid composites. In general, the inclusion of the fibres enhanced the mechanical properties of neat PF. Increase in the fibre content increased the water absorption, however, after 120 h of immersion, all the composites attained an equilibrium state.

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