Wood Preservation Based on In situ Polymerization of Bioactive Monomers. Part 1. Synthesis of Bioactive Monomers, Wood Treatments and Microscopic Analysis

Holzforschung ◽  
2001 ◽  
Vol 55 (4) ◽  
pp. 358-364 ◽  
Author(s):  
Rebecca E. Ibach ◽  
Roger M. Rowell

Summary In situ polymerization of bioactive monomers was investigated as an alternative to conventional preservative treatments. The results are presented in a series of two papers. In Part 1 of the study, six acrylate monomers with covalently bonded, potentially bioactive moieties were synthesized: (1) pentachlorophenolyl acrylate (PCPA), (2) tributyltin acrylate (TBTA), (3) 8-hydroxyquinolyl acrylate (HQA), (4) 5,7-dibromo-8-hydroxyquinolyl acrylate (DBHQA), (5) diethyl-N1N-bis(acryloxyethyl) aminomethyl phosphonate (Fyrol 6 acrylate, F6A), and (6) tetrabromobisphenol A acrylate (TBBPAA). All of these acrylates, except F6A, were purified. Southern pine sapwood samples were treated with acrylate solutions (except TBBPAA) at different retention levels and various amounts of crosslinker (trimethylolpropane trimethacrylate, TMPTM), polymerized in situ, and then acetone leached. The relative amount and location of the polymer in earlywood and latewood of selected samples were determined by scanning electron microscopy and x-ray analysis. Distribution of the compounds varied with treatment. Biological and thermal properties of the treated wood are discussed in Part 2 of this series.

Holzforschung ◽  
2001 ◽  
Vol 55 (4) ◽  
pp. 365-372 ◽  
Author(s):  
Rebecca E. Ibach ◽  
Roger M. Rowell

Summary This paper is the second in a two-part series on in situ polymerization of bioactive monomers as an alternative to conventional preservative treatments. In this part of the study, bioactive monomers were evaluated for their ability to provide resistance to decay and protection against fire. Five bioactive monomers were synthesized: (1) pentachlorophenolyl acrylate (PCPA), (2) tributyltin acrylate (TBTA), (3) 8-hydroxyquinolyl acrylate (HQA), (4) 5,7-dibromo-8-hydroxyquinolyl acrylate (DBHQA), and (5) diethyl-N1N-bis (acryloxyethyl) aminomethyl phosphonate (Fyrol 6 acrylate, F6A). Southern pine sapwood samples were treated with acrylate solutions at different retention levels and with various amounts of crosslinker (trimethylolpropane trimethacrylate, TMPTM), then polymerized in situ. Methyl methacrylate (MMA) was used as the control. Biological resistance to the brown-rot fungus Gloeophyllum trabeum was determined on acetone-leached and unleached samples. PCPA showed some biological efficacy in the absence of crosslinker, but otherwise provided no more protection than did MMA alone. TBTA was biologically effective at all retention levels except with crosslinker concentration ≥10 %. HQA was biologically effective at ≥ 2% retention. F6A was not biologically effective, although unleached wood treated with 10% F6A and 5% or no crosslinker showed some resistance to decay. The 5% DBHQA plus 5% crosslinker treatment was biologically effective in both leached and unleached wood. The effects of the highest treatment level of each monomer, after polymerization, were also evaluated by thermogravimetric analysis. All treatments provided some resistance to fire. The best treatment was 10 % F6A, which resulted in the lowest mass loss (67.0 %) and the lowest maximum temperature of pyrolysis (308.5 °C).


2010 ◽  
Vol 663-665 ◽  
pp. 542-545 ◽  
Author(s):  
Bing Jie Zhu ◽  
Xin Wei Wang ◽  
Mei Fang Zhu ◽  
Qing Hong Zhang ◽  
Yao Gang Li ◽  
...  

The PANI/ITO conducting nanocomposites have been synthesized by in-situ polymerization. The obtained nanocomposites were characterized by X-ray diffraction pattern, scanning electron microscopy and Fourier transform infrared. Electrical conductivity measurements on the samples pressed into pellets showed that the maximum conductivity attained 2.0 ± 0.05 S/cm for PANI/ITO nanocomposites, at ITO doping concentration of 10 wt%. The results of the present work may provide a simple, rapid and efficient approach for preparing PANI/ITO nanocomposites.


2013 ◽  
Vol 457-458 ◽  
pp. 244-247
Author(s):  
Min Li ◽  
Li Guang Xiao ◽  
Hong Kai Zhao

Polyethylene/montmorillonite (PE/MMT) nanocomposites were prepared by in situ polymerization. The morphology of MMT/MgCl2/TiCl4 catalyst and PE/MMT nanocomposites was investigated by scanning electron microscopy (SEM). It can be seen that MMT/MgCl2/TiCl4 catalyst remained the original MMT sheet structures and many holes were found in MMT and the morphology of PE/MMT nanocomposites is part of the sheet in the form of existence, as most of the petal structure. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were carried out to characterize all the samples. XRD results reveal that the original basal reflection peak of PEI1 and PEI2 disappears completely and that of PEI3 become very weak. MMT/MgCl2/TiCl4 catalyst was finely dispersed in the PE matrix. Instead of being individually dispersed, most layers were found in thin stacks comprising several swollen layers.


Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


2014 ◽  
Vol 881-883 ◽  
pp. 1049-1052 ◽  
Author(s):  
Nai Peng ◽  
Cheng Ji Deng ◽  
Hong Xi Zhu

In this paper, the effects of briquetting pressure on the performance of in-situ formed Sialon in Al2O3-C refractory bricks are investigated. The phase compositions and microstructure of the Al2O3-C refractory were investigated by X-ray diffraction (XRD) and scanning electron microscope (SEM).The results show the briquetting pressure hardly has effect on the phase of the sintered specimens, two new phases of Sialon with a Z value of 2 and SiC formed. The micrographs of Sialon crystals have the shape of both column and tabular column, but with a cone tip in the specimens sintered at 200MPa and 300MPa and smooth tip in specimens sintered at 400MPa and 500MPa.


2010 ◽  
Vol 146-147 ◽  
pp. 805-809
Author(s):  
Ji You Gu ◽  
Lan Zhang ◽  
Xian Kai Jiang

The investigations including the acid treatment to multi-walled carbon nano-tubes (MWNTs) and the synthesis of MWNTs/polyurethane composites via in situ polymerization were done. X-ray Photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and dynamic mechanical analysis (DMA) were utilized for evaluating the effects of acid-treated MWNTs on the properties and microstructure of the composites. The results indicated that carboxyl groups could be successfully introduced onto the surface of MWNTs by acid treatment. The dynamic storage modulus and glass transition temperature of composites increased with the existence of MWNTs. The improvement of polyurethane by acid-treated MWNTs performed better compared to raw MWNTs.


2020 ◽  
Vol 70 (1) ◽  
Author(s):  
Xiujie Gong ◽  
Hongtao Zou ◽  
Chunrong Qian ◽  
Yang Yu ◽  
Yubo Hao ◽  
...  

Abstract Purpose The highly efficient degradation bacteria were selected from the humus from the very cold straw in China for many years to construct the in situ degradation bacteria, and the degradation efficiency of corn straw was determined by process optimization. Methods According to the main components of corn straw, through morphological, physiological, and biochemical screening, three highly efficient complementary degradation strains were selected to construct the compound flora, and the degradation efficiency was analyzed by Fourier transform infrared spectrometer, field emission scanning electron microscope, and X-ray diffractometer. Result The corn straw selected in this paper is mainly composed of cellulose (31.99%), hemicellulose (25.33%), and lignin (14.67%). Through the determination of enzyme activity, strain Streptomyces sp. G1T has high decomposition ability to cellulose and hemicellulose but weak utilization ability to lignin; strain Streptomyces sp. G2T has the strongest decomposition ability to cellulose and hemicellulose among the three strains. The decomposition ability of strain Streptomyces sp. G3T to lignin was the strongest among the three strains. Therefore, by compounding the three strains, the decomposition ability has been greatly improved. The optimal process conditions obtained by single factor and response surface method are as follows: pH is 7, temperature is 30 °C, inoculation amount is 5%, rotational speed is 210 rpm, and the weight loss rate of straw is 60.55% after decomposing for 7 days. A large amount of degradation of corn straw can be seen by Fourier transform infrared spectrometer, field emission scanning electron microscope, and X-ray diffractometer. Conclusion Streptomyces sp. G1T, Streptomyces sp. G2T, and Streptomyces sp. G3T screened from straw humus in very cold areas were used to construct in situ degradation bacteria, which had good straw degradation activity and had the potential to be used for straw treatment in cold areas after harvest. This characteristic makes the complex bacteria become a strong competitive candidate for industrial production, and it is also an effective biotechnology in line with the current recycling of resources.


POSITRON ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 52
Author(s):  
Kartika Hajar Kirana ◽  
Mechdi Ghazali ◽  
Luh Ayu Eka Safitri Septiana ◽  
Dini Fitriani ◽  
Eleonora Agustine ◽  
...  

Sungai Citarum merupakan sungai utama yang ada di Provinsi Jawa Barat yang sangat penting bagi kehidupan sosial dan ekonomi. Di bagian hilir, Sungai Citarum ini banyak melewati daerah pemukiman padat penduduk, daerah industri, dan bahkan pesawahan. Oleh karena itu, perlu kajian mengenai kondisi Sungai Citarum salah satunya dengan mengidentifikasi parameter electrical conductivity (EC), total dissolve solid (TDS), pH dan suhu serta karakteristik mineral magnetik pada sedimen melalui analisis sifat magnetik, mineralogi dan morfologi magnetiknya. Pengukuran parameter EC, TDS, pH dan suhu dilakukan secara in situ pada sampel air Sungai Citarum, pengukuran sifat magnetik dilakukan pada sampel sedimen yang telah dipreprasi, sedangkan pengukuran mineralogi dan morfologi dilakukan pada sampel sedimen yang telah diekstraksi. Sifat magnetik sedimen diketahui dari nilai suseptibilitas magnetik dual frekuensi yang diukur menggunakan Bartington Magnetik Susceptibilitymeter, sedangkan mineralogi dan morfologi magnetik diketahui berdasarkan hasil pengukuran scanning electron microscope–energy disperdsive x-ray (SEM-EDS) dan x-ray diffractometer (XRD). Hasil pengukuran secara in situ pada sampel air menunjukkan bahwa rentang nilai EC, TDS, pH dan suhu berturut-turut adalah (200–4120) mS/cm, (100–2060) ppt, 7,34–9,22, dan (26,8–32,6) oC. Sedangkan, hasil pengukuran sifat magnetik menunjukkan bahwa sampel sedimen Sungai Citarum bagian hilir memiliki nilai suseptibilitas magnetik frekuensi rendah (cLF) dengan rentang (65,00–173,80) x 10-8 m3/kg, sedangkan rentang nilai suseptibilitas magnetik frekuensi tinggi (cHF) adalah (64,90–165,70) x 10-8 m3/kg. Dari kedua pengukuran cLF dan cHF diperoleh rentang nilai cFD (%) sebesar 0,15–4,66. Selanjutnya, hasil analisis morfologi dari citra SEM-EDS dan analisis mineralogi berdasarkan pengukuran XRD menunjukkan dominasi jenis mineral magnetik pada sampel sedimen adalah magnetit. Mineral magnetit ini memiliki morfologi berbentuk oktahedral sebagai representasi mineral magnetik alami dan ada pula yang berbentuk spherule sebagai representasi mineral magnetik karena adanya proses oksidasi akibat kehadiran material antropogenik pada sedimen Sungai Citarum bagian hilir.


2014 ◽  
Vol 1052 ◽  
pp. 242-248
Author(s):  
Hong Kai Zhao ◽  
Hong Li Wang

Through the polymerization and grafting reaction of bisphenol A dianhydride and bisphenol A diamine, the polyimide activator (PI activator) of acyl caprolactam end capping is obtained and then the anionic in-situ polymerization modified nylon 6 resin is obtained. Viscosity analysis shows that PI consumption is higher than 0.1 (of monomer mass), the reaction temperature is higher than 160°C, the viscosity rises rapidly in a short time and the rapid polymerization molding can be realized; when PI consumption is higher than 0.15 (of monomer mass), the water absorption of matrix resin will be lower than 1.4%; compared with the nylon resin, its water absorption is significantly lowered and its mechanical property is improved greatly; microscopic analysis shows that PI molecules fail to enter the crystalline phase of the nylon 6 and form lamellar crystals in the nylon matrix, which plays a role of enhancement and obstruction; differential thermal analysis shows that PI reduces the melting enthalpy and melting point temperature of nylon 6 resin, which indicates that PI reduces the crystallization capacity of nylon 6.


2010 ◽  
Vol 663-665 ◽  
pp. 1142-1145
Author(s):  
Yuan Ming Huang ◽  
Bao Gai Zhai ◽  
Qing Lan Ma ◽  
Ming Meng

During the chemical synthesis nanometer-sized particles of ferrous iron oxide were in situ infiltrated into the mesopores in a porous silicon film. The microstructures of porous silicon and the magnetic properties of the nanometer-sized particles of the ferrous iron oxide were characterized with scanning electron microscopy, X-ray diffractometry, and the hysteresis loop measurement, respectively. Our results have demonstrated that the magnetic properties of the nanometer-sized Fe3O4 particles can be dramatically modified when they are confined into the mesopores of the porous silicon film.


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