简介:Akineticequationofnon-isothermalcrystamzationwasderivedbyextendingAvrami’sequationtothenon-isothermalsituation.Morecrystallizationinformationcanbeobtainedfromthiskineticequation.Thecurvesofnon-isothermalandisothermalcrystallizationswereanalysedandcomparedforpoly(ethyleneterephthalate)(PET),andtheresultswerediscussed.
简介:Twohydrogen-bondingadsorbents-macroporouscrosslinkedpoly(P-nitrostyrene)andpoly(p-vinylbenzylamide)-weresynthesized,andtheadsorptionpropertyofphenolfromcyclohexanesolutionontotheadsorbentswasstudied,ThedifferentialadsorptionheastsforvariedadsorptioncapacitiescalculatedfromtheadsorptionisothermsaccordingtotheClaperyron-Clausiusequationlayintherangeofhydrogenbondenergy(8-50kJ/mol),Theadsorptioncapaccityofo-nitrophenolincyclohexanewasmochlessthanthatofphenolunderthesamecondition.Theadsorptioncapacityofphenolfromcyclohexaneontopolyacrylonitrilewasmuchlessthanthatontopoly(p-nitrostyrene)orpoly(p-vinylbenzylamide),Alltheseresultsrevealedthatadsorptionofphenolfromcyclohexanebypoly(p-nitrostyrene)orpoly(p-vinylbenzylamide)isbasedonhydrogen-bonding.
简介:聚氨酯,是在论文介绍的组成的研究的题目,基于Bayer生产的oligocarbonatediolsDesmophenC2100?。组成的建模考虑到作为intervertebral圆盘prostheses的inlay使用材料被执行。聚氨酯被假定是非线性地viscohyperelastic,各向同性、不可压缩。组成的方程从要求的紧张精力功能被导出。橡皮和rheological常数根据试验性的测试被识别,即松驰测试和monotonic以二不同紧张率的单轴的测试,即\(\dot\lambda=0.1\)min1和\(\dot\lambda=1.0\)min1。僵硬张肌被导出并且介绍给Abaqus吗?有限元素(FE)软件以便数字地验证组成的模型。常数鉴定和数字实现的结果证明导出的组成的方程是充分足够的为聚氨酯材料的压力紧张行为建模。
简介:AdsorptionequilibriumexperimentsofphenolontheNKAIIresinareseparatelyconductedinthepresenceandabsenceofultrasoundatambienttemperature.Theisothermofphenolonthepolymeradsorbentinthepresenceofultrasonicfieldisfirstlyreported.Resultsindicatedthattheisothermofphenoldeterminedinthepresenceofultrasoundislowerthanthatintheabsenceofultrasound.Inaddition,experimentsalsoshowthattheuseofultrasoundtotheadsorptionsystemofthephenolaqueoussolutionandNKAⅡresincouldcausetherisingofthetemperatureofthesystemintheorderof6^-C.TheeffectofultrasoundontheisothermofthephenolontheNKAⅡresinmostlyascribestothethermaleffectandthenon-thermaleffectofultrasonicfield.andtheroleofthelaterisgreaterthanthatoftheformer.
简介:Thepaperproposestheidentificationmethodoflinearandnon-linearchromatographicsystem.IsothermsandlumpedmasstransfercoefficientsofchromatographyseparatingisomersorbitolandmannitolonD80adsorbentaredetermined.Theanalysesofrootmeansquareerrorofchromatographyelutioncurvesarecarriedout.Theresultsshowthatthesystemstudiedisnon-linearandthetheoreticalelutioncurvesofthenon-linearchromatographicmodelaremoreaccuratethanthoseofthelinearchromatographicmodel,Resultsofparametersensitivityanalysesshowthatelutioncurvesofnon-linearchromatopraphicseparationaremoresensitivetothevariationofparameter“ai”intheadsorptionisothermsQi=Ci^*/(ai+biCi^*)thantothevariationofparameter"bi”aswellaslumpedmasstransfercoefficients.
简介:Asimpleone-potnon-isocyanaterouteforsynthesizingthermoplasticpolyureasispresented.Insituurethanizationwasconductedfromthering-openingreactionofethylenecarbonatewithpoly(propyleneglycol)bis(2-aminopropylether)andhexanediamine,m-xylylenediamine,ordiethyleneglycolbis(3-aminopropyl)etherat100℃for6hundernormalpressure.Melttransurethanepolycondensationwassuccessivelyconductedat170℃underareducedpressureof399Pafordifferenttimeperiods.Aseriesofnonisocyanatethermoplasticpolyureas(NI-TPUreas)wereprepared.TheNI-TPUreaswerecharacterizedbygelpermeationchromatography,FTIR,1H-NMR,differentialscanningcalorimetry,thermogravimetricanalysis,wide-angleX-raydiffraction,atomicforcemicroscopy,andtensiletest.NI-TPUreasexhibitedMnofupto1.67×10^4g/mol,initialdecompositiontemperatureover290℃,andtensilestrengthofupto32MPa.SeveralcrystallizableNI-TPUreasexhibitedTmexceeding98℃.NI-TPUreaswithgoodthermalandmechanicalpropertieswerepreparedthroughagreenandsimpleone-potnon-isocyanateroute.
简介:一系列聚合物混合从1,3二度(3,4-dicyanophenoxy)被准备苯(3BOCN)和有是的甲基tetrahydrophthalic酐的环氧基树脂树脂治好代理人。治好的行为和混合的治好的动力学被微分扫描热量测定学习。没有3BOCN,有3BOCN的各种各样的内容的混合的明显的激活精力比混合的高。一个模型实验建议在phthalonitrile和环氧基树脂之间没有明显的反应。聚合物混合的热、机械的性质被评估。聚合物混合与整洁的环氧基树脂相比展出高存储模量和字符产量。聚合物混合证明由扫描电子显微镜学(SEM)的可锻的破裂形态学想象。
简介:为综合的一条non-isocyanate线路有优秀热、机械的性质的热塑的聚氨酯被描述。与四个聚乙烯乙二醇木钉融化1,6-bishydroxyethyloxy羰基aminohexane的transurethanepolycondensation,即PEG400,PEG600,PEG1000,或PEG1500,在不同臼齿的比率被进行。有长木钉序列的一系列热塑的polyetherurethanesTPEU被准备。TPEU经由胶化浸透层析被描绘,FTIR,<啜class=“a-plus-plus”>1H-NMR,微分扫描热量测定,thermogravimetric分析,散布的宽角度的X光检查,和张力的测试。TPEU展览T<潜水艇class=“a-plus-plus”>在12.4汦灡之间的g?
简介:Thechaindynamicsofapairofdiblockpoly(styrene-b-butadiene)(PS210-b-PB960)andtriblockpoly(styrene-b-butadiene-b-styrene)(PS200-b-PB1815-b-PS200)copolymersinbothdiluteandsemidilutetoluenesolutionshasbeencomparativelystudiedbydynamiclaserlightscattering.Asexpected,themutualdiffusionofindividualchainchangesintoafastcooperativediffusionofthechainsegments('blobs')betweentwoneighboringentanglementpointsforboththecopolymersasthesolutionchangesfromdilutetosemidilute.Furtherincreasesoftheconcentrationleadtoasecondslowrelaxationmode.Forthetriblockchains,thereexistsanadditionalmiddlerelaxationbetweenthefastandtheslowmodes.with0.33<α<0.44,muchsmallerthan0.75predictedor0.72observedforlinearhomopolymerchainsingoodsolvent.ItimpliesthatthesolventqualityoftolueneforPBmightnotbeasgoodasthatforPS.Duetosuchadifferenceinsolubility,itisreasonabletospeculatethatthePBandPSblocksaretransientlysegregatedinsemidilutesolution.TherelaxationofthesetransientPBandPSricherdomainsleadstotheobservedslowrelaxation.Suchaspeculationissupportedbytheappearanceofanadditionalslowrelaxationmodeinthestudyofpolyisoprene-b-polystyrene-b-polyisopreneinsemidilutesolutionincyclohexane,anon-selectivesolvent,inwhichwealternatedthesolubilitydifferencebyavariationofthesolutiontemperature.
简介:一个非水的暂停polycondensation方法被建议继续为准备的p-phenylenediamine和terephthaloyl氯化物的反应poly(p苯撑terephthalamide)(PPTA)。系统与NMP-CaCl被操作<潜水艇class=“a-plus-plus”>是的2答案驱散的阶段和是的惰性的液体石蜡连续阶段。每NMP-CaCl<潜水艇class=“a-plus-plus”>在石蜡推迟的2答案microdroplet用作polycondensation发生了的microreactor。根据TGA,XRD,红外,SEM和EA的结果,有好质量的PPTA通过这个新奇方法被获得,并且影响这个过程的很多个主要因素被调查为PPTA的准备决定最佳条件。而且,这个二阶段的polycondensation系统与常规解决方案polycondensation方法相比带给许多唯一的优点,包括使反应物离开氧和水的封上的反应环境,HCl到的容易的移动支持更少的精力花费了工具的反应,控制得好的温度和低粘性。