Momwe mungadziwire filimu ya PE ndi filimu ya PVC munjira wamba kapena tsiku lililonse?
Zomwe mukuyang'ana ndi mayeso a Beilstein.Zimatsimikizira kukhalapo kwa PVC pozindikira kukhalapo kwa chlorine.Mufunika nyali ya propane (kapena Bunsen burner) ndi waya wamkuwa.Waya wa mkuwa pawokha umayaka mwaukhondo koma ukaphatikizidwa ndi zinthu zokhala ndi chlorine (PVC) umawotcha wobiriwira.Yatsani waya wamkuwa pamoto (gwiritsani ntchito pliers kuti mudziteteze ndikugwiritsa ntchito waya wautali) kuchotsa zotsalira zosafunikira.Kanikizani waya wotentha ndi chitsanzo chanu cha pulasitiki kuti china chake chisungunuke pawaya kenako lowetsani waya wophimbidwa wa pulasitiki palawilo ndikuyang'ana zobiriwira zobiriwira.Ngati ikuwotcha wobiriwira wowala, muli ndi PVC.
Pomaliza, PE imayaka ndi fungo ngati sera yoyaka pomwe PVC ili ndi fungo lamphamvu kwambiri lamankhwala ndipo imadzizimitsa yokha ikangochotsa lawi lamoto.
"Kodi polyethylene ndi yofanana ndi PVC?"Ayi.
Polyethylene ilibe klorini mu molekyulu, PVC imatero.PVC ili ndi chlorine-substituted polyvinyl, polyethylene alibe.PVC ndi yolimba kwambiri kuposa polyethylene.CPVC kwambiri.PVC imalowa m'madzi m'madzi pakapita nthawi yomwe imakhala yapoizoni, polyethylene satero.PVC imaphulika pansi pa kupanikizika kwambiri (kotero sikoyenera kugwiritsira ntchito mpweya woponderezedwa), polyethylene sichitero.
Onsewo ndi mapulasitiki a thermoformed.
Kodi PVC ndi polyethylene?
PVC, kapena polyvinyl chloride, ndi m'malo mwa polyethylene.Izi zikutanthauza kuti kaboni wina uliwonse wa unyolo umakhala ndi klorini imodzi yolumikizidwa kuphatikiza haidrojeni, osati ma hydrogen awiri omwe amapezeka pa polyethylene.
Kodi pulasitiki ya polyethylene imapangidwa ndi chiyani?
Ethylene
Polyethylene (PE), yopepuka, yosunthika yopangira utomoni wopangidwa kuchokera ku polymerization ya ethylene.Polyethylene ndi membala wa banja lofunika la polyolefin resins.
Kodi polyethylene yolumikizana ndi mtanda ndi chiyani?
Polyethylene ndi unyolo wautali wa hydrocarbon womwe umapangidwa ndikulumikizana motsatizana kwa mamolekyu a ethylene munjira yotchedwa polymerization.Pali njira zosiyanasiyana zochitira izi polymerization.
Ngati chothandizira cha Ti-based inorganic catalyst (Ziegler polymerization) chikugwiritsidwa ntchito, momwe zinthu zimachitikira ndizochepa ndipo polima zomwe zimatsatira zimakhala ngati maunyolo aatali kwambiri a hydrocarbon okhala ndi unsaturation pang'ono (osadzaza -CH=CH2 magulu) mwina ngati gawo. wa unyolo kapena ngati gulu lolendewera.Izi zimatchedwa High Density Polyethylene (HDPE).Ngakhale ma co-monomers monga 1-butene akuphatikizidwa, mulingo wa unsaturation mu polima (LLDPE) umakhala wocheperako.
Ngati chothandizira cha Chromium Oxide chochokera ku inorganic chikugwiritsidwa ntchito, maunyolo amtundu wautali wa hydrocarbon amapangidwanso, koma mulingo wina wosasunthika umawoneka.Apanso izi ndi HDPE, koma ndi nthambi zazitali.
Ngati radical anayambitsa polymerization ikuchitika, pali mwayi kwa maunyolo onse aatali am'mbali mu polima, komanso mfundo zingapo zamagulu osatukuka -CH=CH2 monga gawo la unyolo.Utoto uwu umadziwika kuti LDPE.Ma co-monomers angapo monga vinyl acetate, 1-butene ndi dienes angaphatikizidwe kuti asinthe ndikugwiritsa ntchito tcheni cha hydrocarbon, ndikuphatikizanso kusasunthika kwina m'magulu omwe akulendewera.
LDPE, chifukwa cha kuchuluka kwake kwazinthu zosasinthika, ndizofunika kwambiri pakulumikizana.Iyi ndi njira yomwe imachitika pambuyo pokonzekera mzere woyamba wa polima.LDPE ikasakanizidwa ndi oyambitsa ma radical aulere pa kutentha kokwera, imalumikiza maunyolo osiyanasiyana kudzera pa "kulumikizana" kudzera.unyolo unsaturated mbali.Izi zimabweretsa dongosolo lapamwamba (3-dimensional structure) lomwe limakhala "lolimba".
Maonekedwe a crosslinking amagwiritsidwa ntchito "kukhazikitsa" mawonekedwe enieni, ngati olimba kapena ngati thovu, kuyambira ndi polima yokhazikika, yosamalidwa mosavuta.Njira yofananira ya crosslinking imagwiritsidwa ntchito mu "vulcanization" ya mphira, pomwe polima yofananira yopangidwa kuchokera ku polymerization ya isoprene imapangidwa kukhala cholimba cha 3-dimensional dongosolo pogwiritsa ntchito sulfure (S8) ngati wothandizira kumangirira pamodzi maunyolo osiyanasiyana.Mlingo wolumikizirana ungawongoleredwe kuti ubwereke mipherezero yeniyeni kuzinthu za polima.
Nthawi yotumiza: Oct-11-2022