As a part of enhancing the performance of wood-plastic composites (WPC), polypropylene (PP)/ nanoclay (NC)/ wood flour (WF) nanocomposites were prepared using melt blending and injection molding process to evaluate their thermal stability. Thermogravimetric analysis (TGA) was employed to investigate thermal degradation kinetics of the nanocomposites both dynamic and isothermal conditions. Dynamic scans of the TGA showed an increased thermal stability of the nanocomposites at moderate wood flour concentrations (up to 20 phr, percentage based on hundred percent resin) while it decreased with the addition of 30 phr wood flour. The activation energy (Ea) of thermal degradation of nanocomposites increased when nanoclay was added and the concentration of wood flour increased. Different equations were used to evaluate isothermal degradation kinetics using the rate of thermal degradation of the composites, expressed as weight loss (%) from their isothermal TGA curves. Degradation occurred at faster rate in the initial stages of about 60 min., and then proceeded in a gradual manner. However, nanocomposites with wood flour of 30 phr heated at 300℃ showed a drastic difference in their degradation behavior, and reached almost a complete decomposition after 40 min. of the isothermal heating. The degree of decomposition was greater at higher temperatures, and the residual weight of isothermal degradation of nanocomposites greatly varied from about 10 to 90%, depending on isothermal temperatures. The isothermal degradation of nanocomposites also increased their thermal stability with the addition of 1 phr nanoclay and of wood flour up to 20 phr. But, the degradation of PP100/NC1/MAPP3/WF30 nanocomposites with 30 phr wood flour occurs at a faster rate compared to those of the others, indicating a decrease in their thermal stability.

Sn-3.5Ag 무연합금을 Cu 및 Alloy42 리드프레임에 납땜접합 (solder joint)하고 미세조직, 젖음성, 전단강도, 시효효과를 측정하여 비교하였다. Cu의 경우, 땜납의 Sn기지상안에 Ag(sub)3Sn과 Cu(sub)6Sn(sub)5상이, 그리고 땜납/리드프레임의 경계면에서는 1∼2㎛ 두께의 Cu(sub)6Sn(sub)5상이 형성되었다. Alloy42의 경우, 기지상내에 있는 낮은 밀도의 Ag(sub)3Sn상만이, 그리고 계면에는 0.5∼1.5㎛ 두께의 FeSn(sub)2이 형성되었다. 한편, Cu에 비해 Alloy42 리드프레임에서 퍼짐면적은 크고 접촉각은 작아 더 우수한 젖음성을 나타내었으나, 전단강도는 35%, 연신율은 75%로 낮았다. 180℃에서 1주일간 시효처리 후, Cu 리드프레임에는 계면에 η-Cu(sub)6Sn(sub)5 층외에 ξ-Cu(sub)3Sn층이 성장하였고, Alloy42 리드프레임에는 기지상내에 Ag(sub)3Sn이 구형으로 조대하게 성장하였고, 계면에는 FeSn(sub)2층만이 약 1.5㎛로 성장하였다.

저분자량 (M=1970)을 갖는 poly(styrene)(PS)와 poly(vinymethylether) (PVME)의 블렌드를 열산화시킬 때 PVME의 분자량 감소 속도는 높은 분자량을 갖는 PS와 PVME의 블렌드를 열산화 시킬 때의 PVME 분자량 감소 속도보다 훨씬 느리다. 열산화 과정 동안 PS의 분자량은 변화하지 않았으며 저분자량의 PS의 일부가 산화된 PVME를 분리할 때 함께 녹음을 알 수 있었다. 저분자량의 PS의 모델 화합물로써 2. 4-diphenylpentane을 합성하였고 1%，5%，10%의 모델 화합물을 PVME에 첨가하여 열산화 시켰다. 이 모델 화합물을 첨가하여 PVME의 열산화를 약간 지연시킬 수 있음을 알 수 있었다.

저 분자량(Mw=1970)의 poly(styrene)(PS)와 poly(vinylmethylether)(PVME)의 블렌드를 열 산화시킬 때 저 분자량의 PS의 첨가량이 증가할수록 유도기간이 증가하며 열 산화속도는 감소함을 알 수 있었다. 열 산화과정 동안 저 분자량 PS와 PVME 블렌드는 상 분리를 보이지 않았다. 저 분자량을 갖는 PS와 PVME 블렌드에서 PVME의 산화 속도는 높은 분자량을 갖는 PS와 PVME 블렌드에서 PVME의 열 산화 속도보다 훨씬 느려짐을 보였다.

Selection of a typical four companies products of domestic structural one-component sealant, high temperature, low temperature, room temperature to set up the environment for each of 80, -20, 20 ℃ and the left and right displacement of the test piece 30, 15, 0% of the maximum compression / expansion It was carried out by the repeated fatigue.

This study provides a result of thermal mercury reduction for inventing a mercury recovery technology from the sludgewhich contains high concentration of mercury. Physical, chemical and thermal properties of the sludge were analyzed andmercury degradation at elevated temperatures was investigated to find out the optimum temperature range for thermalrecovery of mercury from the sludge generated from an industrial facility, which contained high concentration of mercury.The study was carried out in the temperature range of up to 650oC from 200oC, and 500~710µm particle size of wastesludge samples were selected from such industries. As primary thermal tests the sludge was heated up to observe weightdegradation at a continuous weight measurable thermogravimetric analyzer and a muffle furnace and the degradationcurves from both devices were found to be well matched. Mercury conversion to gaseous form was investigated fromthe analyzed data of mercury concentrations sampled every 25oC from a muffle furnace. Cold vapor atomic absorptionspectroscopy (CVAAS) Hg analyzer was used for the analysis of mercury content in solid and liquid samples. Most ofmercury was degraded and released as gas phase at the temperature range from 300oC to 550oC, which could be theoptimum temperature of mercury recovery by thermal method for the sludge containing high concentration of mercury.Based on these thermal mercury reduction studies, degradation kinetics study of mercury was conducted to provide thereaction kinetics data for further reactor design to recover mercury using a thermal method.

The pure compound chloromethanes; methyl chloride, methylene chloride, chloroform and carbon tetrachloride were used as a model of chlorocarbon system with Cl/H ratio to investigate thermal stability and hydrodechlorination process of carbon tetrachloride under excess hydrogen atmosphere. The parent thermal stability on basis of temperature required for 99% destruction at 1 second reaction time was evaluated as 875℃ for CH3Cl, 780℃ for CH2Cl2, 675℃ for CHCl3, and 635℃ for CCl4. Chloroform was thermally less stable than CCl4, at fairly low temperatures (<570℃). The decomposition of CCl4, became more sensitive to increasing temperature, and CCl4 was degraded easier than CHCl3 at above 570℃. The number and quantity of chlorinated products decreases with increasing temperature for the product distribution of CCl4 decomposition reaction system. Formation of non-chlorinated hydrocarbons such as CH4, C2H4 and C2H6 increased as the temperature rise and particularly small amount of methyl chloride was observed above 850℃ in CCl4/H2 reaction system. The less chlorinated products are more stable, with methyl chloride the most stable chlorocarbon in this reaction system.