scholarly journals Wood Protection Properties of Quaternary Ammonium Arylspiroborate Esters Derived from Naphthalene 2,3-Diol, 2,2'-Biphenol and 3-Hydroxy-2-naphthoic Acid

2010 ◽  
Vol 63 (10) ◽  
pp. 1423 ◽  
Author(s):  
Jenny M. Carr ◽  
Peter J. Duggan ◽  
David G. Humphrey ◽  
James A. Platts ◽  
Edward M. Tyndall
Keyword(s):  
Molecular Weight ◽  
Quaternary Ammonium ◽  
Hydrolytic Stability ◽  
Wood Preservative ◽  
Environmentally Benign ◽  
High Performing ◽  
Wood Protection ◽  
Naphthoic Acid ◽  
Optimum Balance

In continuation of a program aimed at developing a boron-based, high performing and environmentally benign wood preservative suitable for outdoor use, three lipophilic tetra-n-butylammonium spiroborates, tetra-n-butylammonium bis[naphthalene-2,3-diolato(2-)-O,O′]borate 4, tetra-n-butylammonium bis[2,2′-biphenolato(2-)-O,O′]borate 5 and tetra-n-butylammonium bis[3-hydroxy-2-naphthoato(2-)-O,O′]borate 6 were prepared and tested. The higher molecular weight and lipophilicity of these borates compared with related borates previously examined correlates, in the case of 5 and 6, with significantly enhanced leach resistance while termiticidal activity has been maintained. The racemic spiroborate derived from 2,2′-biphenol 5, in particular, appears to be close to an optimum balance between ease of synthesis, solubility, hydrolytic stability and termiticidal activity.

Wood Protection Properties of Quaternary Ammonium Spiroborate Esters Derived from Alkyl Tartrates

2011 ◽  
Vol 64 (4) ◽  
pp. 495 ◽  
Author(s):  
Jenny M. Carr ◽  
Peter J. Duggan ◽  
David G. Humphrey ◽  
James A. Platts ◽  
Edward M. Tyndall
Keyword(s):  
Tartaric Acid ◽  
Quaternary Ammonium ◽  
Hydrolytic Stability ◽  
Environmentally Benign ◽  
Good Activity ◽  
Leaching Test ◽  
Cellulose Paper ◽  
Butyl Esters ◽  
Wood Protection

Four new tetra-n-butylammonium spiroborates derived from dimethyl, diethyl, di-iso-propyl and di-n-butyl esters of l-tartaric acid have been prepared and their potential as environmentally benign wood protectants investigated. These compounds showed good activity in a no-choice cellulose paper bioassay with Coptotermes acinaciformis termites. The hydrolytic stability of these spiroborates is not high relative to other spiroborates, yet the tetra-n-butylammonium spiroborate derived from di-iso-propyl-l-tartrate showed remarkable permanence in timber in a demanding leaching test.

scholarly journals Modification of Wood with Monoethanolamino-borate by The Data of X-Ray Photoelectron Spectroscopy

2018 ◽  
Vol 196 ◽  
pp. 04005
Author(s):  
Irina Stepina ◽  
Irina Kotlyarova
Keyword(s):  
Particle Size ◽  
Photoelectron Spectroscopy ◽  
Model Compound ◽  
Hydrolytic Stability ◽  
Photoelectron Spectra ◽  
Wood Cellulose ◽  
Rapid Loss ◽  
X Ray ◽  
Wood Protection ◽  
Cellulose Materials

The difficulty of wood protection from biocorrosion and fire is due to the fact that modifiers in use are washed out from the surface of the substrate under the influence of environmental factors. This results in a rapid loss of the protective effect and other practically important wood characteristics caused by the modification. To solve this problem is the aim of our work. Here, monoethanolaminoborate is used as a modifier, where electron-donating nitrogen atom provides a coordination number equal to four to a boron atom, which determines the hydrolytic stability of the compounds formed. Alpha-cellulose ground mechanically to a particle size of 1 mm at most was used as a model compound for the modification. X-ray photoelectron spectra were recorded on the XSAM-800 spectrometer (Kratos, UK). Prolonged extraction of the modified samples preceded the registration of the photoelectron spectra to exclude the fixation of the modifier molecules unreacted with cellulose. As a result of the experiment, boron and nitrogen atoms were found in the modified substrate, which indicated the hydrolytic stability of the bonds formed between the modifier molecules and the substrate. Therefore monoethanolaminoborate can be considered as a non-extractable modifier for wood-cellulose materials.

scholarly journals Performance-tuning of PVA-based gel electrolytes by acid/PVA ratio and PVA molecular weight

2021 ◽  
Vol 3 (3) ◽  
Author(s):  
Saeideh Alipoori ◽  
M. M. Torkzadeh ◽  
Saeedeh Mazinani ◽  
Seyed Hamed Aboutalebi ◽  
Farhad Sharif
Keyword(s):  
Molecular Weight ◽  
Ionic Conductivity ◽  
Charge Carrier Concentration ◽  
Fine Tuning ◽  
Performance Tuning ◽  
Practical Applications ◽  
High Performing ◽  
Flexible Devices ◽  
Gel Electrolytes ◽  
Ion Conducting

AbstractThe significant breakthroughs of flexible gel electrolytes have attracted extensive attention in modern wearable electronic gadgets. The lack of all-around high-performing gels limits the advantages of such devices for practical applications. To this end, developing a multi-functional gel architecture with superior ionic conductivity while enjoying good mechanical flexibility is a bottleneck to overcome. Herein, an architecturally engineered gel, based on PVA and H3PO4 with different molecular weights of PVA for various PVA/H3PO4 ratios, was developed. The results show the dependence of ionic conductivity on molecular weight and also charge carrier concentration. Consequently, fine-tuning of PVA-based gels through a simple yet systematic and well-regulated strategy to achieve highly ion-conducting gels, with the highest ionic conductivity of 14.75 ± 1.39 mS cm-1 have been made to fulfill the requirement of flexible devices. More importantly, gel electrolytes possess good mechanical robustness while exhibiting high-elasticity (%766.66 ± 59.73), making it an appropriate candidate for flexible devices.

The effect of methyl and methoxy substituents on dianilines for a thermosetting polyimide system

2020 ◽  
Vol 32 (7) ◽  
pp. 801-822 ◽  
Author(s):  
John J La Scala ◽  
Greg Yandek ◽  
Jason Lamb ◽  
Craig M Paquette ◽  
William S Eck ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Molecular Weight ◽  
Glass Transition ◽  
Elevated Temperature ◽  
Methyl Substituent ◽  
Glass Transition Temperatures ◽  
High Performing ◽  
Methoxy Substituent ◽  
Acidic Conditions ◽  
Thermal Stability Of

4,4′-Methylenedianiline (MDA) is widely used in high-temperature polyimide resins, including polymerization of monomer reactants-15. The toxicity of MDA significantly limits the manufacturability using this resin. Modifying the substitution and electronics of MDA could allow for the reduction of toxicity while maintaining the high-performing properties of the materials derived from the modified MDA. The addition of a single methyl substituent, methoxy substituent, location of these substituents, and location of the amine relative to the phenolic bridge were modified as were other non-aniline diamines. Various anilines were condensed with paraformaldehyde under acidic conditions to yield dianilines. These dianilines and diamines were reacted with nadic anhydride and 3,3′,4,4′-benzophenonetetracarboxylic dianhydride in methanol to form the polyamic acid oligomers and heated at elevated temperature to form polyimide oligomers. It was found that the molecular weight of the oligomers derived from MDA alternatives was generally lower than that of MDA oligomers resulting in lower glass transition temperatures ( T gs) and degradation temperatures. Additionally, methoxy substituents further reduce the T g of the polymers versus methyl substituents and reduce the thermal stability of the resin. Methyl-substituted alternatives produced polyimides with similar T gs and degradation temperatures. The toxicity of the MDA alternatives was examined. Although a few were identified with reduced toxicities, the alternatives with properties similar to that of MDA also had high toxicities.

Environmentally Benign Adhesive Synthesized by Dispersion Copolymerization of Styrene and Butyl Acrylate

2006 ◽  
Vol 11-12 ◽  
pp. 757-760
Author(s):  
Jun Ying Zhang ◽  
Peng Dou
Keyword(s):  
Molecular Weight ◽  
Butyl Acrylate ◽  
Monomer Concentration ◽  
Environmentally Benign ◽  
Functional Monomer ◽  
Molecular Weights ◽  
Molecular Weight Distributions ◽  
Stabilizer Concentration ◽  
Ethanol Medium ◽  
Weight Distributions

Environmentally benign adhesive was synthesized by dispersion copolymerization of styrene(St) and butyl acrylate (BA) in an ethanol medium with benzoyl peroxide (BPO) as the initiator and poly(vinylpyrrolidone) as the stabilizer in the presence of acrylic acid(AA) as the functional monomer. The effect of the concentration of stabilizer, initiator and functional monomer on the conversions, molecular weights and molecular weight distributions was investigated. The results show that the conversions almost keep invariable with the increasing of stabilizer concentration, but the molecular weights increase and molecular weight distributions decrease. Conversions increase with the increasing of initiator concentration, but the molecular weights and molecular weight distributions decrease. However with the increasing of functional monomer concentration, conversions and molecular weight distributions increase but the molecular weights decrease.

The analysis of high molecular weight quaternary ammonium chlorides

1959 ◽  
Vol 36 (3) ◽  
pp. 93-94 ◽  
Author(s):  
Madolyn Babcock ◽  
David E. Terry ◽  
Albert J. Milun
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Quaternary Ammonium

Synthesis of Quaternary Ammonium Salt from Rosin and its Inhibition to some Wood Decay Fungi

2011 ◽  
Vol 685 ◽  
pp. 291-297 ◽  
Author(s):  
Yan Jin ◽  
Shu Jun Li ◽  
Tao Liang ◽  
Zhi Jun Chen
Keyword(s):  
Reaction Time ◽  
Ammonium Salt ◽  
Quaternary Ammonium ◽  
Quaternary Ammonium Salt ◽  
Wood Decay ◽  
Wood Preservative ◽  
Gravimetric Analysis ◽  
Gloeophyllum Trabeum ◽  
Decay Fungi ◽  
Wood Decay Fungi

Many pine trees could secrete oleo-resin when they were wounded. The oleo-resin was a mixture of turpentine and rosin. After evaporation of volatile turpentine, rosin remained and covered the wound to protect wood from fungi and insects. From this point, rosin protects wood naturally. However, rosin is not bioactive against most wood decay fungi. In this report, a bioactive rosin derivated, quaternary ammonium salt (QAS), was synthesized and its bioactivity against some wood decay fungi was tested. Firstly, the rosin was esterified by epoxy chloropropane with the mole ratio of 1:2, the reaction time of 3.5h at 90°C. The intermediate was 3-rosin acyloxy-2- hydroxypropyl chlorine. Then, the intermediate reacted with demethylamine to produce N-(3-rosin acyloxy- 2-hydroxyl) propyl-N, N dimethylamine at the following conditions: their mole ratio of 1:2, reaction temperature of 80°C and reaction time of 2.5h. Finally, the N-(3-rosin acyloxy-2-hydroxyl) propyl-N, N dimethylamine was quaternized by epoxy chloropropane with the mole ratio of 1:1, the reaction time of 3h at 90°C, and the yield was 72.8%. The chemical structure of the product was identified by FTIR and 1H NMR. The QAS content of the product was characterized by gravimetric analysis with sodium tetraphenylborate as its precipitation reagent, and liquid chromatography analysis (LC) analysis. The antifungal activity of the product was determined by paper-disc method with wood decay fungi such as Trametes versicolor, Gloeophyllum trabeum and wood stain fungi such as Aspergillus niger and Paecilomyces variot Bainier. The anti-fungal experiment results signified that the QAS of rosin is active to these fungi, especially Gloeophyllum trabeum. Since it is produced easily from rosin, which is renewable and not expensive, QAS of rosin could be a potential wood preservative. Further study is planning.

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