Indlela yokubona ifilimu ye-PE nefilimu ye-PVC ngendlela evamile noma yansuku zonke?
Okufunayo ukuhlolwa kwe-Beilstein.Inquma ubukhona be-PVC ngokuthola ukuba khona kwe-chlorine.Udinga ithoshi le-propane (noma i-Bunsen burner) nocingo lwethusi.Intambo yethusi iyodwa iyasha ngokuhlanzekile kodwa uma ihlanganiswa nento equkethe i-chlorine (PVC) ishisa eluhlaza.Shisisa intambo yethusi phezu kwelangabi (sebenzisa impintshisi ukuze uzivikele futhi usebenzise ucingo olude) ukuze ususe izinsalela ezingafuneki.Cindezela intambo eshisayo kwisampula yakho yepulasitiki ukuze enye incibilike ocingweni bese ubuyisela intambo embozwe ngepulasitiki emlilweni bese ubheka okuluhlaza okugqamile.Uma ishisa okuluhlaza okotshani, une-PVC.
Ekugcineni, i-PE ivutha ngephunga elifana ne-wax evuthayo kuyilapho i-PVC inephunga lamakhemikhali elihlabayo futhi izicisha ngokwayo lapho isuswe ilangabi.
"Ingabe i-polyethylene iyafana ne-PVC?"Cha.
I-Polyethylene ayinayo i-chlorine ku-molecule, i-PVC nayo.I-PVC ine-polyvinyl esikhundleni se-chlorine, i-polyethylene ayinayo.I-PVC ngokwemvelo iqinile kune-polyethylene.CPVC ngisho nangaphezulu.I-PVC ifaka ama-compounds emanzini ngokuhamba kwesikhathi anobuthi, i-polyethylene ayinawo.I-PVC iqhuma ngaphansi kokucindezela ngokweqile (ngakho ayifanele izicelo zomoya ezicindezelwe), i-polyethylene ayifuni.
Zombili ziyipulasitiki ye-thermoformed.
Ingabe i-PVC i-polyethylene?
I-PVC, noma i-polyvinyl chloride, ifakwe esikhundleni se-polyethylene.Lokhu kusho ukuthi yonke enye ikhabhoni yeketango ine-chlorine eyodwa enamathiselwe kanye ne-hydrogen, kunama-hydrogen amabili avame ukutholakala ku-polyethylene.
Iyini ipulasitiki ye-polyethylene eyenziwe ngayo?
I-Ethylene
I-Polyethylene (PE), ukukhanya, i-resin yokwenziwa eguquguqukayo eyenziwe nge-polymerization ye-ethylene.I-polyethylene iyilungu lomndeni obalulekile wama-polyolefin resins.
Iyini i-polyethylene ehlanganisiwe?
I-Polyethylene iyi-hydrocarbon enamaketanga amade eyakhiwe ngokuxhumanisa okulandelanayo kwama-molecule e-ethylene ekuphenduleni okwaziwa ngokuthi i-polymerization.Kunezindlela ezahlukahlukene zokwenza lokhu kusabela kwe-polymerization.
Uma i-Ti-based inorganic catalyst (Ziegler polymerization) isetshenziswa, izimo zokusabela zithambile futhi i-polymer ewumphumela isesimweni samaketango amade kakhulu e-hydrocarbon agcwele ane-unsaturation encane kakhulu (amaqembu angagcwele -CH=CH2) noma njengengxenye. weketango noma njengeqembu elilengayo.Lo mkhiqizo ubizwa nge-High Density Polyethylene (HDPE).Ngisho noma ama-co-monomers afana ne-1-butene efakiwe, izinga lokungafinyeleli ku-polymer ewumphumela (LLDPE) lincane.
Uma kusetshenziswa i-Chromium Oxide esekelwe ku-inorganic catalyst, futhi amaketango amade alayini we-hydrocarbon ayakhiwa, kodwa izinga elithile lokungagcwalisi liyabonakala.Nakulokhu futhi lokhu kuyi-HDPE, kodwa ngamagatsha amaketanga amade.
Uma i-radical initiated polymerization yenziwa, kunethuba lawo womabili amaketango amade aseceleni ku-polymer, kanye namaphoyinti amaningana wamaqembu angagcwele -CH=CH2 njengengxenye yeketango.Le resin yaziwa ngokuthi i-LDPE.Ama-co-monomers amaningana afana ne-vinyl acetate, i-1-butene nama-dienes angahlanganiswa ukuze aguqule futhi enze iketango le-hydrocarbon lisebenze, futhi afake nokungafinyeleli okuningi emaqenjini alengayo.
I-LDPE, ngenxa yezinga layo eliphezulu lokuqukethwe okungahlali endaweni, iyinhloko yokuxhumanisa.Lena inqubo eyenzeka ngemva kokulungiswa kwe-polymer ewumugqa wokuqala.Uma i-LDPE ixutshwa neziqalisi ezithile zamahhala emazingeni okushisa aphakeme, ivala amaketango ahlukahlukene “ngokuxhumanisa” ngokusebenzisa.amaketanga aseceleni angagcwele.Lokhu kubangela isakhiwo sezinga eliphezulu (isakhiwo se-3-dimensional) "esiqinile".
Ukusabela kwe-Crosslinking kusetshenziselwa "ukusetha" ukuma okuqondile, okuqinile noma njengegwebu, kuqala nge-polymer ethambile, ephathwa kalula.Inqubo efanayo yokuxhumanisa isetshenziswa "ekuvuvukeni" kwenjoloba, lapho i-polymer eqondile eyenziwe nge-isoprene polymerization yenziwa isakhiwo esiqinile esingu-3-dimensional kusetshenziswa isulfure (S8) njenge-ejenti yokuhlanganisa amaketanga ahlukahlukene.Izinga le-cross-linking lingalawulwa ukuze liboleke izinhloso ezithile ezimpahleni ze-polymer ewumphumela.
Isikhathi sokuthumela: Oct-11-2022