I polymerization ukuphendula

Nokunye okuningi - compounds okuyinto abe nesisindo yamangqamuzana okusezingeni eliphezulu ukufinyelela izinkulungwane eziningana amayunithi. Ukusabela polymerization oluyisisekelo ngezinto zokwakha zesimanje ethola umsebenzi ezahlukene kanye izakhiwo. Ziyakwazi endaweni ukuminyana ongaphakeme zisho okuhlala, uyakwazi ukuthambisa lapho evuthayo futhi kalula ukunqotshwa ekubumbeni, okuvumela ukuthola imikhiqizo ye imiklamo ehlukahlukene nobukhulu. I polymers kukhona inert ukuba ezindaweni onakalisayo, ifa kagesi izakhiwo nangokuvikela futhi akusho adle. Ngenxa izakhiwo zayo eziyingqayizivele, kungenziwa kalula kushintshwe at qophelo zamagama, ukusetshenziswa ngezinto zokwakha zesimanje polymeric njalo uyanda.

Lapho amalahle kanye nokupholisa imikhiqizo zokukhiqiza chemical baziphathe ngezindlela ezimbili.

Ezinye ukuthambisa lapho evuthayo futhi lukhuni lapho selehlile futhi. izinto ezinjalo zihlanganisa imikhiqizo ukulungiselela based elisemandleni, isibonelo, polymerization ukusabela alkenes, okungukuthi, i-polyethylene ne-polypropylene. Zibizwa ngokuthi izinto Thermoplastic. It has izakhiwo efanayo njengoba polyvinyl chloride futhi polystyrene.

Nokunye okuningi lomunye hlobo ingase ukufuthelana kanye kuphela, ngoba lukhuni emva Ukupholisa nokuningi musa ukuthambisa ngaphansi bafudumale. Lezi izinto abizwa ngokuthi thermosetting, bahlanganisa phenol-formaldehyde noma urea-formaldehyde inhlaka. Thermoplastics futhi thermosets kunezimo yabo. Okokuqala akhiqizwa ifomu luyimbudumbudu. Kubo, ngemva amalahle kanye ukuthambisa izinto ukulungele yanoma iluphi, kodwa azikwazi sishiswa ngesikhatsi kokuhlinzwa. Laba okukhiqizwa njengendlela mass Gummy.

ethylene polymerization ukuphendula singatlolwa bunjesi elandelayo: CH2 = CH2 → (-CH2-CH2-) n. Ngaphansi kwezimo ezithile, phambi kwe-umqalisi (bakhetha-mpilo igesi noma isixazululo peroxide organic emafutheni) senzeka phakathi ama-athomu carbon π-tie igebe (ngenye isibopho double) futhi ekhuthaza phakathi inombolo n-Nogo ka kwakhiwa radicals khulula. Ukusabela polymerization okuphuma ngumuntu olukhulu uchungechunge indlela. Isisindo yamangqamuzana okokusebenza polymer kuyinto encike ngqo kwi inombolo n, nge okwandisa yayo likhula. Ngokulungisa nemibandela ukusabela polymerization, ukuhlanganiswa kwezici polyethylene opharetha ephumelelisa ukuthola impahla kanye izakhiwo oyifunayo: fluidity (noma ancibilikise Inkomba), amandla, ukuminyana, Kwe-dielectric Heating nokulahlekelwa tangent, njalo Kwe-dielectric Heating, nabanye.

Synthesis ephezulu ingcindezi polyethylene noma ukusabela polymerization wenziwa sikhungo autoclave noma ijabulise okushisa afinyelela ku-300 ° C futhi ingcindezi 1000 kuya ku-3000 atm. Lokhu kukhipha owawudinga ukushisa. It is isuswe ngamanzi ashisayo okuyinto yanikezwa jacket ophendulayo. I degree of msulwa enikeziwe ukufudumeza ukususwa kwamanzi kuncike kakhulu izinga material kanye nenqubo ukuphepha polymeric. Uma amanzi engaphathwanga kahle bahlanza futhi iqukethe ukungcola eziningi (isib nosawoti ubulukhuni njengoba calcium ne-magnesium cations, anions silicic acid, chlorine, njll), i-ophendulayo jacket kwakhiwa ezifakwa noma insimbi iqala ukukhukhula. Ngenxa yezinguquko ophendulayo odongeni ukushuba ukushabalalisa ukushisa ngaphesheya ubuso bayo iba engalingani, kanye nezinga lokushisa elizosetshenziswa izimo polymerization ingavuthi unmanageable. Nge ukwanda okukhulu lokushisa namachibi we polymer kungenzeka noma noqhekeko kanye lapho kubhujiswa lesi ophendulayo.

I polymerization ukuphendula, ngenxa lapho polyethylene kwakhiwa, kungathatha indawo at lokushisa ephansi futhi ingcindezi. Kodwa lokhu kudinga kulethe. Iqukethe ethylene unreacted, okuyinto ke ehlukanisiwe polymer ukuthi pelletized, le polyethylene okukhiqizwa ngaphansi kwengcindezi ongaphakeme, akube kusakhulunywa ngaye ophendulayo njengoba powder, noma kunalokho ukumiswa ngendlela hydrocarbon kuphela uma polyethylene umfutho ophakeme kusukela ophendulayo njengoba kweminyango ncibilika. I powder wahlukana kuphela futhi ukungcola wageza kusukela kulethe, bese granulated kanye nemishini ekhethekile okuthiwa extruder.

Ngakho, polymerization ukusabela ethylene embonini esetshenziselwa synthesis polyethylene. GOST 16338-85 ukukhiqiza low-ingcindezi polyethylene slurry negesi isigaba amamaki, ngokuvumelana GOST 16337-77 kukhishelwa njengoba ephezulu ingcindezi polyethylene autoclave noma izitembu ijabulise.