• Elastomers and Composites
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• 제39권3호
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• pp.217-227
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• 2004

주사슬에 triad 메소겐 단위와 butylene terephthalate (BT) 단위를 갖는 새로운 액정 중합체를 중축합에 의해서 합성하였다. 합성된 중합체는 nematic 액정상을 보였으며 액정상으로의 전이온도는 $260^{\circ}C$를 보였다. PBT 용액에서 in-situ 중합에 의해서 제조된 TLCP/PBT 블렌드들의 특성 조사는 DSC, TGA, SEM, XRD 그리고 DMTA를 이용하여 이루어 졌다. 블렌드들은 PBT 매트릭스내에서 $0.05{\sim}0.2{\mu}m$ 사이즈를 갖는 잘 분산된 TLCP상들을 보여 주었다. TLCP 농도가 5에서 20wt%로 증가함에 따라서 블렌드내의 순수한 PBT의 ${\Delta}Hm$은 증가하였다. 이는 TLCP가 PBT 매트릭스 내에서 조핵제의 역할을 하였기 때문이다. 블렌드의 기계적 성질들은 TLCP의 농도에 의존하였는데 이 또한 TLCP가 블렌드 내에서 보강제 역할을 하였기 때문이다. 액정상과 PBT 매트릭스 상간에 좋은 계면 접착력을 보여 주었으며 in-situ 중합에 의해서 제조된 블렌드는 용융 블렌딩에 의해서 제조된 블렌드들보다 더욱더 높은 기계적 성질과 잘 분산된 TLCP 도메인들을 보여 주었다.

• Elastomers and Composites
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• 제45권4호
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• pp.256-262
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• 2010

[ $80\;^{\circ}C$ ] 346 bar 상태의 초임계 이산화탄소 내에서 methyl acrylate, ethyl acrylate, butyl acrylate와 glycidyl methacrylate을 중합하였다. 초임계 이산화탄소 분산매에서의 중합을 위하여 aminopropyltriethoxysilane을 사용하여 glycidyl methacrylate를 monoglycidyl ether terminated PDMS에 결합시킨 glycidyl methacrylate linked poly(dimethylsiloxane)(GMS-PDMS)를 계면활성제로 사용하였다. $CO_2$에서 합성된 Poly(alkyl acrylate)의 수율은 acrylate 단량체의 알킬기가 커질수록 낮아졌다. Poly(glycidyl methacrylate)와 poly(methyl acrylate)는 구형으로 만들어진 반면, poly(ethyl acrylate)와 poly(butyl acrylate)는 점성의 액상으로 합성되었다. Poly(glycidyl methacrylate) 입자의 수평균직경은 2.45 ${\mu}m$이며 입자 직경의 분포는 매우 좁았다. poly(methyl acrylate)의 수평균직경은 0.52 ${\mu}m$이며 입자크기는 bimodal로 분포되었다. 초임계 이산화탄소에서 중합된 poly(glycidyl methacrylate)와 poly(alkyl acrylate)들의 유리전이온도는 통상의 방법으로 중합된 poly(glycidyl methacrylate)와 poly(alkyl acrylate)의 유리전이온도보다 4~9 K 높게 측정되었다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.44-63
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• 2000

Situated close to Heathrow Airport, and adjacent to the M4 and M25 Motorways, the site at Axis Park is considered a prime location for business in the UK. In consequnce two of the UK's major property development companies, MEPC and Redrew Homes sought the expertise of Intergeo to remediate the contaminated former industrial site prior to its development. Industrial use of the twenty-six hectare site, started in 1936, when Hawker Aircraft commence aircraft manufacture. In 1963 the Firestone Tyre and Rubber Company purchased part of the site. Ford commenced vehicle production at the site in the mid-1970's and production was continued by Iveco Ford from 1986 to the plant's decommissioning in 1997. Geologically the site is underlain by sand and gravel, deposited in prehistory by the River Thames, with London Clay at around 6m depth. The level of groundwater fluctuates seasonally at around 2.5m depth, moving slowly southwest towards local streams and watercourses. A phased investigation of the site was undertaken, which culminated in the extensive site investigation undertaken by Intergeo in 1998. In total 50 boreholes, 90 probeholes and 60 trial pits were used to investigate the site and around 4000 solid and 1300 liquid samples were tested in the laboratory for chemical substances. The investigations identified total petroleum hydrocarbons in the soil up to 25, 000mg/kg. Diesel oil, with some lubricating oil were the main components. Volatile organic compounds were identified in the groundwater in excess of 10mg/l. Specific substances included trichloromethane, trichloromethane and tetrachloroethene. Both the oil and volatile compounds were widely spread across the site, The specific substances identified could be traced back to industrial processes used at one or other dates in the sites history Slightly elevated levels of toxic metals and polycyclic aromatic hydrocarbons were also identified locally. Prior to remediation of the site and throughout its progress, extensive liaison with the regulatory authorities and the client's professional representatives was required. In addition to meetings, numerous technical documents detailing methods and health and safety issues were required in order to comply with UK environmental and safety legislation. After initially considering a range of options to undertake remediation, the following three main techniques were selected: ex-situ bioremediation of hydrocarbon contaminated soils, skimming of free floating hydrocarbon product from the water surface at wells and excavations and air stripping of volatile organic compounds from groundwater recovered from wells. The achievements were as follows: 1) 350, 000m3 of soil was excavated and 112, 000m3 of sand and gravel was processed to remove gravel and cobble sized particles; 2) 53, 000m3 of hydrocarbon contaminated soil was bioremediated in windrows ; 3) 7000m3 of groundwater was processed by skimming to remove free floating Product; 4) 196, 000m3 of groundwater was Processed by air stripping to remove volatile organic compounds. Only 1000m3 of soil left the site for disposal in licensed waste facilities Given the costs of disposal in the UK, the selected methods represented a considerable cost saving to the Clients. All other soil was engineered back into the ground to a precise geotechnical specification. The following objective levels were achieved across the site 1) By a Risk Based Corrective Action (RBCA) methodology it was demonstrated that soil with less that 1000mg/kg total petroleum hydrocarbons did not pose a hazard to health or water resources and therefore, could remain insitu; 2) Soils destined for the residential areas of the site were remediated to 250mg/kg total petroleum hydrocarbons; in the industrial areas 500mg/kg was proven acceptable. 3) Hydrocarbons in groundwater were remediated to below the Dutch Intervegtion Level of 0.6mg/1; 4) Volatile organic compounds/BTEX group substances were reduced to below the Dutch Intervention Levels; 5) Polycyclic aromatic hydrocarbons and metals were below Inter-departmental Committee for the Redevelopment of Contaminated Land guideline levels for intended enduse. In order to verify the qualify of the work 1500 chemical test results were submitted for the purpose of validation. Quality assurance checks were undertaken by independent consultants and at an independent laboratory selected by Intergeo. Long term monitoring of water quality was undertaken for a period of one year after remediation work had been completed. Both the regulatory authorities and Clients representatives endorsed the quality of remediation now completed at the site. Subsequent to completion of the remediation work Redrew Homes constructed a prestige housing development. The properties at "Belvedere Place" retailed at premium prices. On the MEPC site the Post Office, amongst others, has located a major sorting office for the London area. Exceptionally high standards of remediation, control and documentation were a requirement for the work undertaken here.aken here.