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ID:33929763
大小:18.45 MB
页数:76页
时间:2019-03-02
《聚倍半硅氧烷(poss)改性的led封装硅胶》由会员上传分享,免费在线阅读,更多相关内容在行业资料-天天文库。
1、杭州师范大学硕士学位论文AbstractComparedwithtraditionlightingdevice,light-emittingdiode(LED)exhibitsvariousadvantages,suchashigherluminosityatlowcurrentsandvoltages,longerservicelife,andenvironmentalfriendliness.Becauseofthesefavorablecharacteristics,LEDisbecomingmoreandmorewidespreadly.LEDdevicemade
2、upwithchips,wires,brackets,conductiveadhesivesandpackagingmaterials.Thefunctionofthepackagingmaterialsistoprotectthechips.ThepackagingmaterialshavebecomeoneofthemostimportantfactorsforLEDdevice.Thepackagingmaterialsshouldhavehightransparencyandgood.antiultravioletability.t,Atpresent,packa
3、gingmaterialsofcommonLEDdevicearemainlyofepoxyresins.Buttheepoxyresinshaveseveraldisadvantages.Atfu'st,epoxyresinswillturnyellowafterusingacontentoftime,whichwilldecreasethetransmittance.Secondly,thehigherthermalresistanceofepoxyresinleadstotherapidriseofthechip’Stemperatureandaccelerates
4、thedecayoftheLEDdevices.Whatisworse,therapidthermalexpansionwillmakethedeviceopencircuit..SiliconematerialsareidealpackagingmaterialsforLEDbecauseoftheiroutstandingperformances.Inthisthesis,theoctavinylpolyhedraloligomericsilsesquioxane(OVPOSS)andeightpolyfourmethylammoniumsilicatewerepre
5、paredtomodifiedthevinylsiliconeoilviaringopeningpolymerization.Thenthevinylsiliconeoilmixedwithacertainproportionofhydrogensiliconeoil,platinumcatalystandcured.Theresultsaleasfollows:(1)Ring—openingcopolymerizationofOVPOSSwithD3topreparethePOSSmodifiedvinylsiliconeoil.Thefeaturesofthecopo
6、lymerizationwereinvestigatedsymatically.Thenthemodifiedvinylsiliconeoil、hydrogen-containedsiliconeoilandplatinumcatalystweremixturedtopreparedsiliconematerialsforLEDpackaging.Thehardnessofthematerialisintherangeof0-30ShoreA.(2)TheTMAOHisthecatalystforthering-openingcopolymerizationofD4and
7、Iv杭州师范大学硕士学位论文Abstract现M锄forpreparinghighrefractivemodifiedvinylsiliconeoil.Thecopolymerizationwasinvestigatedindetail.Thenthevinylsiliconeoil,hydrogen-containedsiliconeoilandplatinumcatalystweremixturedtogethertopreparesiliconematerialsforLEDpackaging.Thehardnessof
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