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In recent years, development of computers and progress of calculation algorithms promote understanding of the various mechanisms of characteristics of electrical insulating materials using quantum chemical calculation. This paper deals with quantum chemical calculation of the relative permittivity εr of dicyclopentadiene and tricyclopentadiene resins expected as the next generation electrical insulating...
In this study, the hypothesized thermal conductive monomers were synthesized by bi-phenol derivatives and monomers with vinyl functional groups, and then the purified products were identified by1H-NMR spectrum. The thermal properties of synthesized monomers were measured by DSC and TGA instruments. The resin prepared by synthesized monomers, crosslinking agent and initiator with thermal conductivity...
As the interests in wearable devices are become growing, flexible substrates is being extensively investigated. In this study, new hybrid underfill for a low temperature process to create an electrical interconnection system on flexible substrate was studied. Hybrid underfill material is composed with underfill materials and 54Bi27In19Sn solder powder which has melting temperature at 83°C. For the...
In semiconductor industry, deflashing is one of the important process steps during manufacturing of the semiconductor product. The term ‘deflashing’ is used to describe the removal of excessive mold bleed and resin bleed as a result of molding process in the assembly of the plastic devices as shown in figure 1. Mold bleed is black color material and is due to leakage while resin bleed is transparent...
For recent major low CTE and dielectric material is epoxy resin system, it must add a large amount of filler and flame retardant to decrease CTE value, Dk, and achieve UL-94 V0 standard. In this study, low CTE AI were synthesized by incorporating biphenyl- or naphthalene- type diisocyanate with rigid and symmetrical structure, and then reacted with naphthalene type epoxy forming low CTE resins. The...
Agarwood, also known as Gaharu in Malaysia, is a fragrant and valuable international commodity harvested from Aquilaria and Gyrinops tree species. The quality of agarwood depends on many factors, such as the quality of its wood resin, smell and origin. Current methods for determining its quality rely on human experts. However, an automated approach would be more suitable for mass production. In this...
This paper presents a review on agarwood and its quality determination. It was found that Aquilaria Malaccensis is the main species in Malaysia and Indonesia. The agarwood has different quality or grades; similarly its essential oil. They are traded at different price according to their quality. Scientific reason showed that chemical compositions of agarwood make them different from each other, thus...
The annual bark yield in Canada is as much as 17millionm3. Currently, more than half of the bark is incinerated or landfilled and the remainder of the bark is mainly used as a cheap source of energy in saw/pulp mills. Both bark incineration and landfilling can lead to environmental problems. Due to the abundance of ash in bark and the lower sintering point of bark ash than that of wood ash, the combustion...
The aim of this research is to study the characterization of modified poplar wood. A chemical impregnation was utilized before the poplar wood was dried and compressed in a multilayer hot-press drying kiln. The results showed that with the compression rate of 31.7%, the basic density, the over dried density and air-dried density of treated wood increased 25%, 75% and 74%, respectively. The bending...
In order to study the pyrolysis characteristic of biomass components, especially the influence of urea formaldehyde resin (UF) on different components, compositional study on thermogravimetric analysis was carried out on cellulose, xylan, lignin and UF resin. The three main components as well as the ones mixed with UF resin ran the same heating pattern. TGA analysis indicated that the first weight...
Aspen has traditionally been used as the only feedstock for OSB panel production in Canada over the past 30 years. With aspen becoming less available to most Canadian OSB mills, the OSB industry has to use alternative wood species such as white birch and sugar maple as a partial substitute for aspen in OSB production. This has a significant influence on OSB panel performance. To address this issue,...
This paper instructs the development situation of polymer-nanomaterial prepared by nanometer materials modifying PMUF, and puts forward to synthetizing nano-CaCO3 by the metathesis method in homemade PMUF system. And the copolymerization resin PMUF-CaCO3 formed is dipped by the vacuum-pressure into the poplar veneers to prepare wood inorganic nanometer composite (WINC). The thermal stability and hardness...
The bamboo-based composites can significantly contribute to the efficiency and utilization of bamboo. In this work, the chemical components, volume fraction of bamboo tissues, characteristics of single fiber, structure and mechanical properties of ci bamboo and moso bamboo were used to evaluate the suitability for manufacturing bamboo-based composites, and then the bamboo-based fiber composites (BFC)...
Poly (vinyl alcohol) (PVA) is a water-soluble synthetic polymer with excellent adhesive property. But the water resistance is poor. The aim of this study is to explore the suitable formula for PVA cross-linking with sodium silicate to form new kind of wood adhesive which has the perfect bonding strength as well as water resistance. When PVA and sodium silicate are mixed directly, they then become...
The possibility of obtaining modified petroleum resin, whose structure is determined by means of 1H-NMR spectroscopy and GLC, by copolymerization of various fractions of liquid products of pyrolysis and butyl methacrylate under the influence of cationic catalysts is shown. The yield of modified resins decreases in the following pattern: C9 > DF > CF. The number of aromatic units reduces as their...
Vinyl ester was prepared from diglycidyl ether of bisphenol A and methacrylic acid with Styrene as diluent.The vinyl ester resin is used as crosslinking agent for unsaturated polyester resin (Prepared from maleic anhydride, propylene glycol, pthalic anhydride as 1∶2∶1 ratio) with Styrene as diluent using free radical initiator (MEKP) and accelerator the blending with UPR & vinyl ester is carried...
The derivative of ceoftiam hexetil, which include a pair of isomers (the ratio of the isomers 1:1), was prepared and identified in this article. Two ?-3 isomers were separated by MCI-GEL CHP20P resin, and their structures were identified by NHR and HPLC. The ratio of the two isomers was calculated nearly 1:1, corresponded to the theoretical data. The ?-2 ceoftiam hexetil, which is side product of...
Medicinal mushroom polysaccharides from submerged culture have lots of important biological activities, such as antitumor, immunomodulating, antioxidation and so on. In order to improve the biological activities of the polysaccharides, pigments impurities produced in the fermentation process have to be eliminated by a suitable technology before polysaccharides purification and application. 28 kinds...
In this paper, a new kind of benzocyclobutene-functionalized siloxane monomer, 1,3,5,7,-tetramethyl-1,3,5,7-tetra[2'-(4'-benzocyclobutenyl)]vinylcyclotetra-siloxane (CYC-BCB), is synthesized and characterized. For comparison, the commercialized resin, 1,1,3,3-tetramethyl-1,3-bis [2'-(4'-benzocyclobutenyl)]vinyldisiloxane (DVS-BCB) is also prepared. Partially polymerized resins, P-DVS-BCB, P-CYC-BCB,...
The Gudao crude oil was separated into four fractions (saturated, aromatic, resin, asphaltene) by means of fluid-solid adsorption chromatogram, then elementary composition, molecular weight, IR spectrum of crude oil and the four fractions were investigated. The result showed that the molecular weight of asphaltene is the largest, and the degree of unsaturation and content of hetero atom is highest...
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