蜜胺树脂论文：蜜胺树脂聚乙二醇三(2-羟乙基)异氰脲酸酯增韧热解动力学

1、增韧热解动力学【中文摘要】蜜胺泡沫塑料是一种具有阻燃、吸音降噪、隔热、耐热稳定、卫生无毒、后加工性能优良的绿色环保的高性能泡沫塑料。但纯蜜胺树脂是含有刚性三嗪环结构的三维立体网络结构的热固性高聚物,交联密度大，发泡性能差，制成的泡沫体硬度较大，柔韧性较差,不易拉伸。因此,树脂韧性的提高，脆性的降低，成为开发新型发泡用蜜胺树脂的重要目标。本论文选取聚乙二醇（PEG-200）、三（2-羟乙基）异氰脲酸酯（THEIC）两种改性剂分别对蜜胺树脂进行增韧改性，以树脂体系的动力粘度作为改性树脂的评价指标，由正交实验结合单因素实验优化改性树脂的聚合工艺条件（如反应物摩尔比、反应时间、改性剂添加量、固含量等）

2、；通过红外光谱、核磁共振碳谱、热失重对改性树脂的结构、热稳定性进行表征和鉴定，并通过测定改性树脂的拉伸强度和断裂伸长率对其韧性进行表征；最后对改性树脂的热解动力学进行研究，为进一步了解发泡用蜜胺树脂的耐热性及其应用提供参考价值。实验得出,PEG改性树脂的适宜工艺条件为：体系pH值为9.5,n（F）/n（M）为2.8,固含量为75%,反应时间为50min,PEG添加量为5%THEIC改性树脂的适宜工艺条件为：体系pH值为9.5,n（F）/n（M）为2.8,固含量为75%反应时间为90min,THEIC添加量为10%PEGTHEIC参与了体系反应，成功地植入蜜胺树脂的分子链中,加大了三嗪环之间的距

3、离，可起到增韧改性的作用，但改性剂加入对树脂的耐热性能有一定的降低；当PEG添加量为5%,THEIC添加量为10%寸,对应的改性树脂的拉伸强度和断裂伸长率基本达到发泡用树脂GFDA-7勺要求,进一步得出适合发泡用蜜胺树脂的适宜工艺条件。得到PEG改性树脂热解动力学方程为：【英文摘要】Melaminefoamisakindofhigh-performaneegreenfoamwithFlame-retardant,acousticnoise,thermalinsulation,heatstable,healthnon-toxic,easypost-processingperformance.Wi

4、delyusedinarchitecturalacoustics,automotive,industrialnoise,industrialinsulation,railtransportation,aerospacenavigation,equipmentinstallationandairconditioningsystems,cleaningsystems,etc.Butpuremelamineresinwasathermosettingpolymer,anditformedacross-linkingnetworkstructureinthreedimensions,arigidity

5、triazineringincludedinthenetworkstructure,thusresultedinthatthemelamineresinhasapoorformingfoamperformanee.Foamformedishardandcrispwithpoormechanicalproperties,lowintensity,smalldeformationcapacity,poortensileandflex.Therefore,improvementoftoughnessanddecreasementofbrittlenesswereanimportantgoalonde

6、velopingnewfoamingmelamineresin.ThemelamineresinwhichwasrespectivelymodifiedwithPEG-200andtri(2-hydroxyethyl)isocyanuratewasstudiedinthispaper.Dynamicviscosityofresinsystemisusedastheevaluationindexofmodifiedresin.Theorthogonalexperimentandsinglefactorexperimentwereusedtoinvestigatethepolymerizingre

7、actionconditionsofmodifiedresin(suchasmaterialratio、reactiontime、amountofmodifier、solidcontent)onthepolymerizationreactionsystem;Structureandthermalstabilityofmodifiedresinwerecharacterizedandidentifiedusinginfraredspectroscopy,nuclearmagneticresonancecarbonspectra,thermalgravimetric;Toughnesswascha

8、racterizedthroughdeterminingthetensilestrengthandfractureelongationofthemodifiedresins,andtheoptimalreactionconditionsofappropriatefoamingmodifiedresinareobtained;Finally,Throughstudyingthepyrolysiskineticsofthemodifiedresin,providerefereneevaluesforfurtherunderstandingtheheatresistaneeandapplicationofthefoamingmelamine.TheresultsindicatethattheappropriateconditionsofPEGmodifiedresinwereasfollows,pHis9.5,n(F)/n(M)=2.8,solidcontentis75%,reactiontimeis50min,theamountofPEGis5%;theappropriateconditionsofTHEICmodifiedresinw