PET

Polyethylene terephthalate (nthawi zina amalembera poly (ethylene terephthalate), ofupikitsidwa PET, Pete, kapena PETP yatha kapena PET-P, ndizofala kwambiri Thermoplastic polima utoto wa Polyester Banja ndipo imagwiritsidwa ntchito ngati ulusi zilipo pazamadzimadzi ndi zakudya, thermoforming popanga, komanso kuphatikiza ndi utomoni wagalasi wama utomoni waukadaulo.

Angatchulidwenso ndi dzina la mtundu Dacron; ku Britain, Terylene; kapena, ku Russia ndi Soviet Union wakale, Lavsan.

Zambiri zomwe PET zimapanga padziko lapansi ndizopangira ulusi (wopitilira 60%), ndikupanga mabotolo pafupifupi 30% yakufunidwa kwapadziko lonse lapansi. Potengera zolemba nsalu, PET imadziwika ndi dzina lodziwika, Polyester, pomwe mawuwo PET nthawi zambiri amagwiritsidwa ntchito pokhudzana ndi kuyika. Polyester imapanga pafupifupi 18% ya ma polima padziko lonse lapansi ndipo ndi yachinayi yomwe imapangidwa kwambiri polima; polyethylene(Pe), polypropylene (PP) ndi polyvinyl chloride (PVC) ndi yoyamba, yachiwiri komanso yachitatu, motsatana.

PET imakhala opukutidwa zigawo za monomer ethylene terephthalate, ndikubwereza (C₁₀H₈O₄) mayunitsi. PET imakonda kubwezerezedwanso, ndipo imakhala nambala yake 1 monga chizindikiro chake chobwezeretsanso.

Kutengera ndi kachitidwe kake ndi mbiri ya kutentha, polyethylene terephthalate ikhoza kukhalapo ngati amorphous (transparent) komanso ngati ma polisitala a semi-crystalline. Ma semicrystalline amatha kuwonekera poyera (tinthu tating'onoting'ono <500 nm) kapena opaque ndi yoyera (kukula kwake mpaka ma micrometer ochepa) kutengera kapangidwe kake kama kristalo ndi kukula kwake. Kutentha kwake bis (2-hydroxyethyl) terephthalate ikhoza kupangidwa ndi mgwirizano zochita pakati asidi terephthalic ndi ethylene glycol ndi madzi ngati chotuluka, kapena kusintha zochita pakati ethylene glycol ndi dimethyl terephthalate ndi methanol monga chochokera. Kuphatikiza kwamphamvu kudutsa a kuchuluka zomwe ochita monomers (anachita atangomaliza kumene / kupatsirana) ndi madzi monga chotuluka.

Mayina
Dzina la IUPAC Poly (ethyl benzene-1,4-dicarboxylate)
Odziwika
Nambala ya CAS	25038-59-9
achidule	PET, PET
Zida
Mankhwala a mankhwala	(C10H8O4)n
Unyinji wa Molar	kusintha
kachulukidwe	1.38 g / cm3 (20 ° C), amorphous: 1.370 g / cm3, galasi limodzi: 1.455 g / cm3
Mfundo yosungunula	> 250 ° C, 260 ° C
Malo otentha	> 350 ° C (kuwonongeka)
Kutentha m'madzi	pafupifupi osabadwa
Kutentha kwa kutentha	0.15 mpaka 0.24 W m-1 K-1
Chiwerengero cha refractive(nD)	1.57-1.58, 1.5750
Thermochemistry
Mwachindunji kutentha mphamvu (C)	1.0 kJ / (kg · K)
Zogwirizana
Related Akatswiri	Terephthalic asidi Ethylene glycol
Pokhapokha ngati zanenedwa kwina, zambiri zimaperekedwa kuti zizipezeka mkhalidwe wamba (pa 25 ° C [77 ° F], 100 kPa).

ntchito

Chifukwa PET ndichida chabwino kwambiri chotchingira madzi ndi chinyontho, mabotolo apulasitiki opangidwa kuchokera ku PET amagwiritsidwa ntchito kwambiri pakumwa zakumwa zozizilitsa kukhosi (onani carbonation). M'mabotolo ena apadera, monga omwe amapangidwira zakumwa za mowa, PET imasoka gawo lina la mowa wa polyvinyl (PVOH) kuti muchepetse kuperewera kwa mpweya wake.

PET yochokera ku BET Kanemayo (yemwe nthawi zambiri amadziwika ndi dzina lake lamalonda, "Mylar") amatha kuwunikiranso ndikusandutsa kanema wazitsulo kuti muchepetse kuloleza kwake, ndikuupangitsa kuwunikira komanso kuwonekera (MPET). Izi ndizothandiza pamapulogalamu ambiri, kuphatikizapo zakudya zosinthika CD ndi mafuta kutchingira. Onani: "mabulangeti amalo“. Chifukwa cha mphamvu zake zamakina apamwamba, filimu ya PET imagwiritsidwa ntchito nthawi zambiri popanga tepi, monga chonyamulira cha tepi ya maginito kapena kuthandizira matepi omatira ovutikira.

PET Yopanda maziko Thermofed kupanga matayala opaka ndi matuza. Ngati Pststallizable PET imagwiritsidwa ntchito, matayala amatha kugwiritsidwa ntchito pazakudya zozizira, chifukwa amathandizira kutentha ndi kuzizira kwa uvuni. Mosiyana ndi amorphous PET, yemwe ndi wowonekera, PET kapena CETET imakhala yakuda.

Ikadzazidwa ndi tinthu tating'onoting'ono tating'ono kapena ulusi, imakhala yolimba komanso yolimba.

PET imagwiritsidwanso ntchito ngati gawo lapansi m'maselo owonda kwambiri amaola.

Terylene imagawidwanso m'miyeso yazing'amba kuti ithandize kuvala zingwe pamene akudutsa padenga.

History

PET inali ndi setifiketi mu 1941 ndi a John Rex Whinfield, a James Tennant Dickson ndi owalemba ntchito ku Calico Printers 'Association of Manchester, England. EI DuPont de Nemours ku Delaware, USA, adagwiritsa ntchito chikwangwani cha Mylar mu Juni 1951 ndipo adalandira kulembetsa mu 1952. Lidakali dzina lodziwika bwino kwambiri logwiritsidwa ntchito mufilimu ya polyester. Mwini wake wamalonda ndi DuPont Teijin Films US, mgwirizano ndi kampani yaku Japan.

Ku Soviet Union, PET idapangidwa koyamba m'ma laboratories a Institute of High-Molecular Compounds ya USSR Academy of Sciences mu 1949, ndipo dzina lake "Lavsan" ndi chidule chake.laборатории Инститck вoses соединений Академии наук Сіst.

Botolo la PET linayatsidwa mu 1973 ndi Nathaniel Wyeth.

Thupi

PET m'chilengedwe chake ndi utoto wopanda utoto, wonyezimira ngati crystalline. Kutengera momwe amapangidwira, PET imatha kukhala yolimba yolimba, ndipo ndiyopepuka kwambiri. Zimapanga mpweya wabwino komanso chinyezi chokwanira, komanso chotchinga chabwino chomwa mowa (chimafuna chithandizo chowonjezera cha "zotchinga") ndi zosungunulira. Ndi yamphamvu komanso yosagonjetsedwa. PET imakhala yoyera ikakumana ndi chloroform komanso mankhwala ena monga toluene.

Pafupifupi 60% crystallization ndi malire apamwamba pazogulitsa, kupatula ulusi wa polyester. Zogulitsa zomveka bwino zimatha kupangidwa ndi kupolerera koyambirira kwa mungu pang'ono pansi pa T_g galasi kusintha kutentha kupanga olimba amorphous. Monga galasi, ma amorphous PET amapangidwa ma molekyulu awo akapanda kupatsidwa nthawi yokwanira kuti azikonzekera mwadongosolo, mwa kristalo pamene kusungunuka kuziziririka. Kutentha kutentha mamolekyulu amakhala oundana m'malo mwake, koma, ngati kutentha kokwanira mphamvu kumabwezeretsedwanso mwa kutentha pamwamba pa T_g, zimayambanso kusunthanso, kulola kuti makhiristo asungunuke ndikukula. Ndondomeko amadziwika kuti olimba-boma crystallization.

Akaloledwa kuziziritsa pang'onopang'ono, polima wosungunukayo amapanga zinthu zonyezimira kwambiri. Zinthu izi zatero ma spherulites yokhala ndi zazing'ono zambiri makhwala mukamayimba kuchokera ku amorphous solid, m'malo mopanga galasi lalikulu limodzi. Kuwala kumakhala kumafalikira pomwe kumadutsa malire pakati pa makristalo ndi madera amorphous pakati pawo. Kubalalachi kumatanthauza kuti makristasi a PET ndi opaque komanso oyera nthawi zambiri. Kujambula kwa CHIKWANGWANI ndi chimodzi mwazinthu zochepa zomwe zimapanga mafakitale zomwe zimapanga chinthu chimodzi chokhala ngati galasi.

Maso amkati

Chimodzi mwazofunikira kwambiri za PET chimatchedwa chidwi cham'maso (IV).

Kukhuthala kwamkati kwazinthuzo, komwe kumapezeka powonjezera mpaka zero ndende ya viscosity yachibale mpaka ndende yomwe imayesedwa mu ma decilit pa gramu (dℓ / g). Kukongola kwa mkati kumadalira kutalika kwa maunyolo ake a polymer koma alibe magawo chifukwa chakuzunguliridwa ndi zero. Kutalikirana kwakanthawi kochepa kumakhala kolowera kwambiri pakati pa unyolo chifukwa chake kukweza kwambiri. Kutalika kwa chingwe cha batani inayake ya utomoni kumatha kuwongoleredwa mkati kuchuluka.

Makulidwe amitundu yonse ya PET:

Fayilo yopanda

0.40-0.70 Textile

0.72-0.98 Ukadaulo, chingwe chotopetsa

Gawo lamafilimu

0.60-0.70 Mtengo wa BOPET (makanema okongoletsedwa a PET)

0.70-1.00 Kalasi ya Sheet Thermoforming

Gawo la botolo

0.70-0.78 Mabotolo amadzi (phwete)

0.78-0.85 Mpweya wabwino wowerengeka kabati

Monofilament, pulasitiki yokonza mapulani

1.00-2.00

Kusaka

PET ndiye hybroscopic, kutanthauza kuti imamwetsa madzi m’malo ozungulira. Komabe, pamene PET "yonyowa" imeneyi itenthedwa, madzi ma hydrolyzes ndi PET, ikuchepetsa mphamvu zake. Chifukwa chake, utomoni usanapangidwe mu makina owumba, uyenera kupukuta. Kuyanika kumatheka pogwiritsa ntchito a wofunitsitsa kapena ma dryer PET isanadyetsedwe muzinthu zosinthira.

Mkati mwa choumitsira, mpweya wowuma wouma umaponyedwa pansi pa hopper wokhala ndi utomoni kuti uzitha kudutsa pellets, kuchotsa chinyezi panjira yake. Mpweya wonyowa wotentha umachoka pamwamba pa hopper ndipo umadutsa koyamba kozizira, chifukwa ndikosavuta kuchotsa chinyezi mumlengalenga ozizira kuposa mpweya wotentha. Mpweya wonyowa womwe umatuluka kenako umadutsa pabedi la desiccant. Pomaliza, mpweya wozizira womwe umachoka pabedi la desiccant umatenthedwanso ndikuwotcha ndikuubwezeretsanso munjira yomweyo. Nthawi zambiri, chinyezi chotsalira mu utomoni chiyenera kukhala chochepera 50 magawo miliyoni (magawo amadzi pa magawo miliyoni a utomoni, kulemera) asanakonzedwe. Nthawi yokhalamo choumitsira sayenera kukhala yayifupi kuposa maola anayi. Izi ndichifukwa choti kuyanika kwa zinthuzo pasanathe maola anayi kungafune kutentha pamwamba pa 4 ° C, pamlingo womwewo hydrolysis zimayamba mkati mwa mathalauza asanapukute.

PET ikhoza kuyanikanso muzowuma mpweya wouma wamphepo. Zouma zapanikizika sizigwiritsanso ntchito mpweya wowuma. Mpweya wouma, wotenthetsedwa umasunthidwa kudzera m'matumba a PET ngati pomauma, kenako umaperekedwa kumlengalenga.

Zamgululi

Kuphatikiza pakuyera (wosawerengeka) PET, PET yosinthidwa ndi kopolymerization iliponso.

Nthawi zina, zinthu zosintha za Copolymer ndizofunikira pantchito inayake. Mwachitsanzo, cyclohexane dimethanol (CHDM) ikhoza kuwonjezeredwa ku mafupa a msana wa polymer m'malo mwa ethylene glycol. Popeza nyumbayi ndi yayikulu kwambiri (maatomu 6 owonjezera a kaboni) kuposa gawo la ethylene glycol lomwe amalowa m'malo mwake, siligwirizana ndi maunyolo oyandikana nawo momwe gulu la ethylene glycol limakhalira. Izi zimasokoneza crystallization ndikuchepetsa kutentha kwa polima. Mwambiri, PET yotere imadziwika kuti PETG kapena PET-G (Polyethylene terephthalate glycol-modified; Eastman Chemical, SK Chemicals, ndi Artenius Italia ndi ena opanga ma PETG). PETG ndichodziwika bwino cha amorphous thermoplastic yomwe imatha kupangidwira jekeseni kapena pepala kutulutsa. Ikhoza kukhala yonyezimira pokonza.

Njira ina yodziwika ndi asidi isophthalic, m'malo mwa ena 1,4- (pa-) cholumikizidwa adabali mayunitsi. The 1,2- (chita) kapena 1,3- (cholinga-) kulumikizana kumatulutsa ngodya mumtengowo, zomwe zimasokonezeranso kukokana.

Ma pololymer oterewa ndiwothandiza pamapulogalamu ena owumba, monga Thermoforming, yomwe imagwiritsidwa ntchito mwachitsanzo kupanga matayala kapena chithuza kuchokera ku filimu ya Co-PET, kapena pepala la amorphous PET (A-PET) kapena PETG. Kumbali inayi, crystallization ndiyofunikira pakugwiritsa ntchito kwina komwe kukhazikika kwamakina ndi mawonekedwe ndizofunikira, monga malamba okhala. Mabotolo a PET, kugwiritsa ntchito ochepa mankhwala a isophthalic acid, CHDM, Diethylene glycol (DEG) kapena ma comonomers ena atha kukhala othandiza: ngati ndalama zochepa chabe zomwe zimagwiritsidwa ntchito, crystallization imachedwa koma osapewedwa kwathunthu. Zotsatira zake, mabotolo amapezeka kudzera Tambasula nkhuni ("SBM"), zomwe zonse ndizowoneka bwino komanso crystalline wokwanira kukhala chotchinga chokwanira kununkhira komanso ngakhale mpweya, monga kaboni dayokisaidi muzakumwa za kaboni.

kupanga

Polyethylene terephthalate amapangidwa kuchokera ethylene glycol ndi dimethyl terephthalate (C₆H₄(NKHA₂CH₃)₂) kapena asidi terephthalic.

Zoyambayo ndi kusintha Zochita, pomwe zotsalazo ndi mgwirizano kuchitapo.

Njira ya Dimethyl terephthalate

In dimethyl terephthalate ndondomekoyi, mankhwalawa ndi ethylene glycol owonjezera amachitika posungunuka pa 150-200 ° C ndi chothandizira choyambira. Methanoli (CH₃OH) amachotsedwa ndi distillation kuyendetsa zomwe zikuyenda patsogolo. Ethylene glycol yochulukirapo imachotsedwa kutentha kwambiri mothandizidwa ndi zingalowe m'malo. Gawo lachiwiri la transesterification limafikira pa 270-280 ° C, ndikuphatikizanso kosiyanasiyana kwa ethylene glycol.

Zomwe zimachitika ndizotsatira:

Choyamba

C₆H₄(NKHA₂CH₃)₂ + 2 CHIFUKWA₂CH₂OH → C.₆H₄(NKHA₂CH₂CH₂O)₂ + 2 CH₃OH

Gawo lachiwiri

n C₆H₄(NKHA₂CH₂CH₂O)₂ → [(CO) C₆H₄(NKHA₂CH₂CH₂O)]_n + n HOCH₂CH₂OH

Njira ya Terephthalic acid

Mu asidi terephthalic ndondomeko, esterification ya ethylene glycol ndi terephthalic acid imachitika mwachindunji pakulimbikira pang'ono (2.7-5.5 bar) ndi kutentha kwambiri (220-260 ° C). Madzi amachotsedwa poyankha, ndipo amachotsedwanso mosalekeza ndi distillation:

n C₆H₄(NKHA₂H)₂ + n HOCH₂CH₂OH → [(CO) C₆H₄(NKHA₂CH₂CH₂O)]_n + 2n H₂O

Kutsitsidwa

PET imayang'aniridwa ndi mitundu yosiyanasiyana yazonyansa pakukonza. Zoyipa zazikulu zomwe zimatha kuchitika ndi hydrolytic, ndipo mwina chofunikira kwambiri, makutidwe ndi okosijeni. PET ikanyoza, zinthu zingapo zimachitika: kusinthanitsa, tcheni kukwapula chifukwa kuchepetsedwa maselo kulemera, mapangidwe a acetaldehydendipo nsanja ("Gel" kapena "fish-eye" mapangidwe). Kutulutsa thupi kumachitika chifukwa chopanga makina osiyanasiyana okhudzana ndi chromophoric kutsatira chithandizo chamatenthedwe kwakutali pamafunde okwera. Izi zimakhala zovuta ngati zofunikira za polima ndizokwera kwambiri, monga momwe amagwirira ntchito. Kuwonongeka kwa matenthedwe ndi kutentha thupi kumapangitsa kuti zinthu zisayende bwino komanso magwiridwe antchito.

Njira imodzi yochepetsera izi ndikugwiritsa ntchito a kopolymer. Comonomers monga CHDM kapena asidi isophthalic chepetsa kutentha ndikusungunula kutentha kwa PET (kofunika makamaka pamene zinthuzi zigwiritsidwa ntchito popanga mabotolo). Chifukwa chake, utomoni ungapangike mwapulasitiki pamtunda wotsika komanso / kapena ndi mphamvu yotsika. Izi zimathandizira kupewa kufooka, kuchepetsa zinthu za acetaldehyde zomwe zimamalizidwa kukhala zovomerezeka (ndiye kuti, zosawoneka). Mwaona ophunzirawo, pamwamba. Njira ina yowonjezera kukhazikika kwa polima ndikugwiritsa ntchito zolimbitsa thupi, makamaka ma antioxidants monga ma phosphites. Posachedwapa, kukhazikika kwa maselo azinthu pogwiritsa ntchito mankhwala opangidwa ndi nanostructured adaganiziridwanso.

Acetaldehyde

Acetaldehyde ndi chinthu chopanda utoto, chosasunthika ndi fungo la zipatso. Ngakhale zimapangidwa mwachilengedwe zipatso zina, zimatha kuyambitsa kukoma m'madzi am'mabotolo. Mitundu ya Acetaldehyde mwa kuwonongeka kwa PET kudzera pakusamalira nkhaniyo. Kutentha kwakukulu (PET imavunda pamwamba pa 300 ° C kapena 570 ° F), zovuta zazikulu, kuthamanga kwa extruder (kutulutsa ubweya wambiri kumakweza kutentha), komanso nthawi yayitali yokhala ndi mbiya zonse zimathandizira kupanga acetaldehyde. Acetaldehyde ikapangidwa, ina yake imasungunuka m'makoma a chidebe kenako chimayambitsa mu mankhwala omwe amasungidwa mkati, kusintha kukoma ndi kununkhira. Ili siliri vuto kwa osagwiritsa ntchito (monga shampoo), wamafuta azipatso (omwe ali kale ndi acetaldehyde), kapena zakumwa zolimba ngati zakumwa zozizilitsa kukhosi. Kwa madzi am'mabotolo, komabe, ma acetaldehyde okhutira ndizofunikira, chifukwa, ngati palibe chomwe chimagunda fungo, ngakhale zotsika kwambiri (magawo 10 pa biliyoni m'madzi) a acetaldehyde atha kutulutsa kukoma.

Antimoni

Antimoni (Sb) ndi chinthu chachitsulo chomwe chimagwiritsidwa ntchito ngati chothandizira m'njira zamagulu monga antiyoni trioxide (Sb₂O₃) kapena antimony triacetate pakupanga PET. Pambuyo pakupanga, chiwonetsero chambiri chowoneka chitha kupezeka padziko lapansi. Izi zitha kuchotsedwa ndikutsuka. Kusemphana kumakhalanso mu zinthu zokhazokha ndipo, motero, kusamukira ku chakudya ndi zakumwa. Kuwonetsa PET kuwira kapena kuwonera kungachititse kuchuluka kwa antimony kwambiri, mwina kupitilira milingo yayikulu ya USEPA. Malire amadzi akumwa omwe amayesedwa ndi WHO ndi magawo 20 pa biliyoni (WHO, 2003), ndipo malire akumwa madzi ku USA ndi magawo 6 pa biliyoni. Ngakhale antimony trioxide ndi ya poizoni wochepa akamamwedwa pakamwa, kupezeka kwake kumakhudzabe. Anthu aku Switzerland Federal Office Yazaumoyo anafufuza kuchuluka kwa kusamuka kwa antimony, kuyerekezera madzi omwe ali mu PET ndi galasi: Kuchuluka kwa antimoni m'madzi m'mabotolo a PET anali okwera, komabe anali pansi pamlingo wololedwa. Swiss Federal Office of Public Health idatsimikiza kuti antimony ochepa amasamuka kuchokera ku PET kupita m'madzi am'mabotolo, koma kuti chiwopsezo chazovuta zomwe zimatsika ndizochepa (1% ya "kudya tsiku lililonse”Wotsimikiza ndi WHO). Pambuyo pake (2006) koma kafukufuku wofalitsidwa kwambiri adapeza kuchuluka kwa antimoni m'madzi m'mabotolo a PET. WHO yatulutsa kuwunika kwa chiwopsezo cha antimoni m'madzi akumwa.

Madzi azipatso amatenga (omwe palibe malangizo omwe akhazikitsidwa), komabe, omwe amapangidwa ndikuyika botolo ku PET ku UK amapezeka kuti ali ndi 44.7 µg / L ya antimoni, pamwamba pamalire a EU madzi apampopi Zambiri "5 pa µg / L.

Biodegradation

nocardia ikhoza kuyipitsa PET ndi enzyme ya esterase.

Asayansi aku Japan apatula bacterium Ideonella sakaiensis yomwe ili ndi ma enzyme awiri omwe amatha kuwononga PET kukhala tizinthu tating'onoting'ono tomwe bacteria akhoza kugaya. Colonia wa Ine ndiiensis imatha kupatula kanema wapulasitiki pafupifupi milungu isanu ndi umodzi.

Safety

Ndemanga yofalitsidwa mu Zochitika Zachilengedwe Zachilengedwe M'mwezi wa Epulo 2010 adanenanso kuti PET ikhoza kudzipereka zosokoneza endocrine Pazinthu zodziwika bwino komanso kufunsidwa kafukufuku pamutuwu. Njira zomwe zikuphatikizidwa zikuphatikiza leaching a phthalates komanso kuphunzitsa kwa tsankho. Nkhani yofalitsidwa mu Zolemba za Kuwunikira Zachilengedwe mu Epulo 2012 akuti madzi osankhidwa yosungidwa m'mabotolo a PET amakhala m'malire ovomerezeka a EU ngakhale atasungidwa pang'ono kutentha mpaka 60 ° C (140 ° F), pomwe zomwe zili m'mabotolo (madzi kapena zakumwa zoziziritsa kukhosi) nthawi zina zimatha kupitirira malire a EU pasanathe chaka chosungira chipinda kutentha.

Botolo kukonza zida

Pali njira ziwiri zoyambira kuumba mabotolo a PET, gawo limodzi ndi magawo awiri. Popanga magawo awiri, makina awiri osiyana amagwiritsidwa ntchito. Wogwiritsa ntchito jakisoni woyamba amaumba preform, yomwe imakhala ngati chubu choyesera, ndipo ulusi wa kapu ya botolo udapangidwa kale kuti ukhale. Thupi la chubu limakulirakulira kwambiri, chifukwa lidzakhuta m'mayendedwe ake achiwiri Tambasula nkhuni.

Mu gawo lachiwiri, mauthengawo amatenthetsedwa mwachangu kenako amadzisungunulira mbali ziwiri kuti apange botolo lomaliza. Zosintha (mabotolo osagwiritsidwa ntchito) tsopano zimagwiritsidwanso ntchito ngati zotakasika komanso zopezeka mwapadera; kupatula maswiti odabwitsa, machaputala ena a Red Cross amawagawira ngati gawo la pulogalamu ya Vial of Life kwa eni nyumba kuti asungire mbiri yachipatala kwa omwe akuyankhira mwadzidzidzi. Ntchito ina yomwe imagwiritsidwa ntchito popangira ma preforms ndiyophatikizira mu geocaching yakunja.

M'makina opanga gawo limodzi, njira yonse yochokera ku malamba mpaka chida chotsirizidwa imayendetsedwa mkati mwa makina amodzi, ndikupangitsa kuti ikhale yoyenera kwambiri pakupanga mawonekedwe osasintha (pakuumba), kuphatikiza mitsuko, mawonekedwe ozungulira, mawonekedwe a chucha etc. kuchepa kwa malo, kusanja kwazinthu ndi nyonga, komanso mawonekedwe apamwamba kwambiri kuposa omwe angapangidwe ndi magawo awiri.

Makina obwezeretsanso zinthu

Mu chaka cha 2016, akuti mwina mamiliyoni 56 a PET amapangidwa chaka chilichonse.

Ngakhale ma thermoplastics ambiri amatha, amakonzanso, Kubwezeretsa botolo la PET ndiwothandiza kuposa ntchito zina zambiri zamapulasitiki chifukwa cha kukwera mtengo kwatsankho komanso kugwiritsa ntchito PET kwa madzi ogwiritsiridwa ntchito kwambiri komanso mabotolo a zakumwa zoziziritsa kukhosi. PET ili ndi nambala yodziwitsa Ya 1. Zomwe zimagwiritsidwa ntchito kwambiri PET yobwezeretsanso ndi polyester CHIKWANGWANI, zingwe, ndi zotengera zopanda chakudya.

Chifukwa chokonzanso PET ndi kuchuluka kwa zinyalala za pambuyo pa ogula mwanjira yamabotolo, PET ikupeza msika wogulitsa mwachangu ngati ulusi wamapauta. Makampani a Mohawk idatulutsidwa nthawi zonse mu 1999, 100% yaogwiritsa ntchito olemba 17% yobwezeretsanso PET. Kuchokera nthawi imeneyo, mabotolo oposa XNUMX biliyoni abwezerezedwanso mu CHINSINSI CHA carpet. Pharr Yarns, wogulitsa kwa opanga makapeti ambiri kuphatikiza Looptex, Dobbs Mills, ndi Berkshire Flooring, amatulutsa fayilo ya CarF (yochulukirapo yopitilira) PET yokongoletsa ya PET yokhala ndi zinthu zosachepera 25% zomwe ogula abwezeretsa.

PET, monga momwe amapangira ma pulasitiki ambiri, amakhalanso woyenerera kutaya mafuta (kuphedwa,, momwe imapangidwira ndi kaboni, hydrogen, ndi oksijeni, zomwe zimakhala ndi zothandizira (koma zopanda sulufu). PET ili ndi mphamvu zamagetsi ofewa.

Mukabwezeretsanso polyethylene terephthalate kapena PET kapena poliyesitala, munjira ziwiri ziyenera kusiyanitsidwa:

1. Kubwezeretsanso mankhwala kumayendedwe koyambirira komwe kwayeretsedwa asidi terephthalic (PTA) kapena dimethyl terephthalate (DMT) ndi ethylene glycol (EG) pomwe kapangidwe ka ma polima kawonongekeratu, kapena mkati mwake ngati bis (2-hydroxyethyl) terephthalate
2. Kukonzanso kwamakina komwe zida zoyambirira za polymer zimasungidwira kapena kukonzedwanso.

Kubwezeretsanso mankhwala kwa PET kumakhala kotsika mtengo kokha kungogwiritsa ntchito mizere yoposa matani 50,000 / chaka. Mizere yotere imatha kuwoneka, ngati, konse, mkati mwamasamba opanga kwambiri polyester. Kuyesera kochulukirapo kwa mafakitale kukhazikitsa mbewu zobwezeretsazi monga mankhwala zidapangidwa kale koma sizinaphule kanthu. Ngakhale kubwezeretsa kwachuma ku Japan sikunakhale kopambana mpaka pano. Zifukwa ziwiri izi ndi izi: poyamba, zovuta za mabotolo amtundu wosasinthika wopitilira muyeso imodzi pamalo amodzi, ndipo, chachiwiri, mitengo ikukwera komanso kusasinthika kwa mitengo yamabotolo osonkhanitsidwa. Mitengo yamabotolo osindikizira idakwera mwachitsanzo pakati pa 2000 ndi 2008 kuchokera pa 50 Euro / ton to more 500 Euro / ton in 2008.

Kukonzanso kwamakina kapena kufalitsa mwachindunji kwa PET m'chigawo cha polymer kumayendetsedwa mosiyanasiyana masiku ano. Njira izi ndizofanana ndi zamakampani ang'onoang'ono komanso apakatikati. Kugwiritsa ntchito mtengo kumatha kuchitika kale ndi zolimba zamtunda mkati mwa matani 5000-20,000 / chaka. Potere, pafupifupi mitundu yonse ya zinthu zomwe zasinthidwa ndikufalitsa nkhani ndizotheka lero. Njira zosiyanasiyana zobwezeretsazi zikukambidwa mwatsatanetsatane pambuyo pake.

Kupatula mankhwala oipitsa ndi kuwonongeka zinthu zomwe zimapangidwa pakagwiritsidwe kake koyamba ndikugwiritsa ntchito, zosafunikira zamagetsi zikuyimira gawo lalikulu la kuwonetsa zosayera zilizonse mukuyenda kokonzanso. Zinthu zobwezerezedwanso zimayambitsidwa m'njira zopangira, zomwe poyambirira zimapangidwira zida zatsopano zokha. Chifukwa chake, kusanja bwino, kupatukana ndi njira zoyeretsera zimakhala zofunikira kwambiri polyester yokonzanso bwino.

Tikamayankhula za mafakitoni obwezeretsanso polyester, timangoyang'ana kwambiri za kubwezeretsanso mabotolo a PET, omwe amagwiritsidwa ntchito pakumwa zamadzi zamtundu uliwonse ngati madzi, zakumwa zoziziritsa kukhosi za kaboni, timadziti, mowa, masoso, zotakasa, mankhwala am'nyumba ndi zina. Mabotolo ndiosavuta kusiyanitsa chifukwa cha mawonekedwe ndi kusasinthasintha kwawo komanso kupatukana ndi mitsinje yopanda pulasitiki mwina mwa zokha kapena njira zosanja bwino. Makampani okhazikitsanso ma polyester azinthu zitatu zazikulu:

• Kutoleretsa botolo la PET ndikutaya zinyalala: kukonza zinthu zotayidwa
• Kupanga oyera mabotolo oyera: kupanga ma flake
• Kutembenuka kwa mapepala a PET kupita ku zinthu zomaliza: kukonza kwa flake

Katundu wapakatikati kuchokera pagawo loyamba ndi zinyalala za mabotolo okhala ndi nkhani ya PET yoposa 90%. Mitundu yodziwika kwambiri yamalonda ndi bale koma yopandidwa kapena ngakhale yotayirira, mabotolo omwe adadulidwa kale ndiofala pamsika. Gawo lachiwiri, mabotolo omwe atengedwa amasinthidwa kukhala oyera ma PET botolo. Gawo ili limakhala locheperako komanso lovuta komanso losavuta kutengera mtundu womaliza. Mukakhala gawo lachitatu, ma botolo a PET amapangira zinthu zamtundu uliwonse monga filimu, mabotolo, CHIKWANGWANI, CHINSINSI.

Kuphatikiza pa kubwezeretsako kwakunja kwa botolo la post-(ogula), kuchuluka kwa njira zobwezeretsera, zomwe zimawonongeka sizimatuluka pamalo opangidwira pamsika waulere, ndipo m'malo mwake zimagwiritsidwanso ntchito munthawi yomweyo. Mwanjira imeneyi, zinyalala za fiber zimagwiritsidwanso ntchito mwachindunji kupanga fayilo, zinyalala za preform zimagwiritsidwanso ntchito mwachindunji kuti zizipanga ma preform, ndipo zinyalala zamafilimu zimagwiritsidwanso ntchito mwachindunji kuti zipange filimu.

Kubwezeretsa botolo la PET

Kuyeretsa ndi kuwonongeka

Kupambana kwa lingaliro lililonse lobwezeretsanso kumabisika pakuyeretsedwa ndi kuchotsedwa pamalo oyenera panthawi yokonza komanso pamlingo wofunikira kapena wofunidwa.

Nthawi zambiri, zotsatirazi zikugwira ntchito: Kumayambiriro kwa ndondomekoyi zinthu zakunja zimachotsedwa, ndipo pamene izi zichitidwa bwino, ndondomekoyi imakhala yogwira mtima kwambiri.

Pamwamba Pulasitiki kutentha kwa PET mu 280 °C (536 °F) ndi chifukwa chake pafupifupi zonyansa zonse zomwe zimapezeka m'chilengedwe monga PVC, PLA, alireza, zamkati zamatabwa ndi ulusi wamapepala, polyvinyl nthochi, Sungunulani zomatira, ma coloring othandizira, shuga, ndi mapuloteni Zotsalira zimasandulika kukhala zinthu zowononga mitundu zomwe, nawonso, zimatha kutulutsa zinthu zowononga zowononga. Kenako, kuchuluka kwa zolakwika mu unyolo wa polima kumawonjezeka kwambiri. Kukula kwa tinthu tating'onoting'ono ndikotakata kwambiri, tinthu tating'onoting'ono tating'onoting'ono ta 60-1000 µm - zomwe zimawoneka ndi maso komanso zosavuta kusefa - zikuyimira zoyipa zochepa, popeza mawonekedwe ake onse ndi ochepa ndipo kuchepa kwachangu kumatsika. Mphamvu ya tinthu tating'onoting'ono, tomwe, chifukwa ndi tambiri, timachulukitsa zolakwika za polima, ndizochulukirapo.

Mawu akuti "Zomwe diso silikuwona pamtima sangadandaule nazo" zimawerengedwa kuti ndizofunikira kwambiri pazinthu zambiri zobwezeretsanso. Chifukwa chake, kuphatikiza pakusanja bwino, kuchotsera zodetsa zooneka ndi kusungunuka kwazosefera kumathandizira kwambiri pankhaniyi.

Mwambiri, titha kunena kuti njira zopangira mabotolo a PET m'mabotolo omwe amasonkhanitsidwa ndizotheka mosiyanasiyana monga mitsinje yazinyalala yosiyana ndi kapangidwe kake ndi kapangidwe kake. Potengera ukadaulo palibe njira imodzi yokha yochitira. Pakadali pano, pali makampani ambiri amisiri omwe akupereka zida zopangira ma flake, ndipo ndizovuta kusankha mtundu umodzi kapena china. Komabe, pali njira zomwe zikugawira ambiri mwa mfundozi. Kutengera mawonekedwe ndi kusadetsedwa kwa zinthu zolowetsera, njira zotsatirazi zikugwiritsidwa ntchito.

1. Kutsegulira kwa Bale, kutsegula kwa briquette
2. Kusanja ndi kusankha mitundu yosiyanasiyana, ma polima akunja makamaka PVC, zinthu zakunja, kuchotsa filimu, mapepala, galasi, mchenga, nthaka, miyala, ndi zitsulo.
3. Kusamba osadula
4. Kudula koyala kapena kuphatikiza kutsuka kusanachitike
5. Kuchotsa miyala, galasi, ndi zitsulo
6. Kupukusa mpweya kuti muchotse kanema, pepala, ndi zilembo
7. Pogaya, youma ndi / kapena yonyowa
8. Kuchotsa ma polima ochepera (makapu) mwa kusiyana kachulukidwe
9. Kutsuka
10. Kusamba kwa Caustic, ndi kuyang'anitsitsa pamtunda, kusungitsa chidwi chamkati ndi kudziwongola
11. Kuyeretsa
12. Kutsuka kwamadzi oyera
13. Kusaka
14. Kuwombera mpweya
15. Zodziwikiratu zokhazokha
16. Dongosolo la madzi ndi luso lamadzi
17. Kuwongolera kwapamwamba

Zodetsa ndi zolakwika zakuthupi

Kuchuluka kwa zodetsa zilizonse ndi zolakwika zakuthupi zomwe zimadziunjikira polymeric zikuchulukirachulukira, pokonzanso komanso kugwiritsa ntchito ma polima - poganizira ntchito yomwe ikukula, ndikukula komaliza komanso kubwerezabwereza. Momwe mabotolo a PET amakonzedweranso, zolakwika zomwe zatchulidwa zitha kusungidwa m'magulu otsatirawa:

1. Magulu omaliza a Reyes polyester OH- kapena COOH- matembenuzidwe amasinthidwa kukhala magulu omwalira kapena osagwira ntchito, mwachitsanzo, kupanga magulu omaliza a vinyl ester kudzera m'matumbo kapena decarboxylation ya terephthalate acid, momwe magulu a OH- kapena COOH- omalizira akuwonongeka kwa ntchito ya mono. zinthu ngati ma mono-carbonic acid kapena ma alcohols. Zotsatira zimachepetsedwa pokhapokha pakukonzanso polycolfund kapena kukonzanso SSP ndikukulitsa kugawa kwamisempha.
2. Gawo lotsirizira limasunthira kulunjika kwa magulu omaliza a COOH omwe amapangidwa kudzera mukuwonongeka kwa mafuta ndi oxidative. Zotsatirazi zikuchepa, komanso kuwonjezeka kwa kuwonongeka kwa asidi mothandizika pa nthawi ya matenthedwe chifukwa cha chinyezi.
3. Chiwerengero cha macromolecule a polyfunctional chikukula. Kuchulukitsidwa kwa zolakwika za gels ndi kulumikizidwa kwa nthambi zazitali.
4. Chiwerengero, kuchuluka, komanso mitundu yosiyanasiyana yachilengedwe komanso michere yakunja ikukula. Ndi nkhawa iliyonse yatsopano yamafuta, zinthu zachilengedwe zakunja zimatha kuwonongeka. Izi zikuthandizira kumasulidwa kwazinthu zina zothandizira pakuwonongeka ndi zinthu zopaka utoto.
5. Magulu a Hydroxide ndi peroxide amapanga pansi pazinthu zopangidwa ndi polyester pamaso pa mpweya (oxygen) ndi chinyezi. Izi zimathandizira pang'onopang'ono ndi kuwala kwa ultraviolet. Panthawi yopweteketsa mankhwala, ma hydro peroxides amachititsa mpweya kuwongolera, omwe amachititsa kuti zinthu zisaipitsidwe ndi oxidative. Kuwonongeka kwa hydro peroxides kumayenera kuchitika isanachitike chithandizo choyambirira chamafuta kapena mkati mwa pulasitiki ndipo mutha kuthandizidwa ndi zowonjezera zoyenera ngati antioxidants.

Poganizira zolakwika zomwe zimatchulidwa pamwambapa ndi zosayera, pamakhala kusintha kosinthika kwa zinthu zotsatirazi za polymer munthawi iliyonse yobwezeretsanso, zomwe zimapezeka ndi kusanthula kwa mankhwala ndi mankhwala.

Makamaka:

• Kuchulukitsidwa kwa magulu omaliza a COOH
• Kuchulukitsa kwa nambala yamtundu b
• Kuchulukitsa kwa mivi (zinthu zowoneka bwino)
• Kuchuluka kwa oligomer
• Kuchepetsa kusefera
• Kuchuluka kwa zinthu zamakampani monga acetaldehyde, formaldehyde
• Kuchuluka kwa zotulutsa zakunja
• Kuchepa kwa utoto L
• Kuchepa kwa chidwi cham'maso kapena mawonekedwe amphamvu
• Kuchepa kwa kutentha kwa crystallization ndi kuwonjezeka kwa kuthamanga kwa crystallization
• Kuchepa kwa zinthu zamakina monga kulimba kwamphamvu, elongation panthawi yopuma kapena zotanuka modulus
• Kufutukula kagawidwe ka maselo

Kubwezeretsanso mabotolo a PET ndi njira yokhazikika yamafakitale yomwe imaperekedwa ndi makampani osiyanasiyana opanga uinjiniya.

Kusintha zitsanzo za polyester yobwezerezedwanso

Njira zobwezeretsanso ndi poliyesitala zimakhala zosiyanasiyana monga momwe makina opanga amapangira pellets oyambira kapena kusungunuka. Kutengera kuyera kwa zinthu zobwezerezedwanso, poliyesitala itha kugwiritsidwa ntchito masiku ano munjira zambiri zopangira poliyesitala monga kuphatikiza polima namwali kapena kuphatikizira polima mobwerezabwereza 100%. Zina mwapadera monga kanema wa BOPET wonenepa kwambiri, mapulogalamu apadera ngati kanema wowoneka bwino kapena ulusi kudzera pa FDY-kupota pa> 6000 m / min, microfilaments, ndi michere yaying'ono amapangidwa kuchokera ku polyester ya namwali yokha.

Kusintha kosavuta kosinthira mabotolo

Njirayi imakhala yosinthira zinyalala m'mabotolo, kupukuta ndi kuyika matenthedwe, kupukutira pulasitiki ndi kusefa, komanso kupanga pelletizing. Product ndi amorphous kukonzanso chidwi chodabwitsa mu mndandanda wa 0.55-0.7 dℓ / g, kutengera momwe kuyimitsiratu kwa ma PET kwachitika.

Zapadera ndiz: Acetaldehyde ndi oligomers amapezeka m'matumba a m'munsi; mamasukidwe akayendedwe amachepetsedwa, ma pellets ndi amorphous ndipo amayenera kuti akhale osalala komanso owuma asanapange kukonzanso.

Kukonzedwa ku:

• Filimu ya A-PET ya Thermoforming
• Zowonjezera pakupanga anamwali a PET
• Mtengo wa BOPET filimu yonyamula
• Botolo la PET resin ndi SSP
• Ulusi wapaveti
• Pulasitiki yaumisiri
• Mafilimu
• Osati nsalu
• Mikwingwirima yonyamula
• CHIKWANGWANI champhamvu.

Kusankha njira yobwezeretsanso kumatanthauza kukhala ndi njira yowonjezera yotembenuzira yomwe, kumbali imodzi, yamphamvu komanso yotsika mtengo, ndikuwononga mafuta. Kumbali inayo, njira yothandizira anthu kuchita izi ikupereka izi:

• Kwambiri kusungunuka
• Kuwongolera kwapakatikati
• Kusintha ndi zowonjezera
• Kusankhidwa kwazogulitsa ndikulekanitsa ndi mtundu
• Kukonzanso kusinthasintha kunachuluka
• Kuyanjana kwamtundu wabwino.

Kupanga PET-pellets kapena ma flakes mabotolo (botolo kupita ku botolo) ndi A-PET

Izi zimachitika chimodzimodzi ndi zomwe tafotokozazi; komabe, ma pellets omwe amapangidwa amaphatikizidwa mwachindunji (mosalekeza kapena mosalekeza) ndikuyika polycyensation yolimba (SSP) pamalo owuma kapena oyatsira ma chubu. Pakadutsidwe kameneka, mamasukidwe akayendedwe a 0.80-0.085 d is / g amamangidwanso ndipo, nthawi yomweyo, zinthu za acetaldehyde zimachepetsedwa kukhala <1 ppm.

Mfundo yakuti ena opanga makina ndi omanga mizere ku Ulaya ndi USA amayesetsa kuti apereke njira zobwezeretsanso, mwachitsanzo, njira yotchedwa botolo-to-botolo (B-2-B), monga LEMBANI, Nyenyezi, URRC kapena BÜHLER, cholinga chake ndikupereka umboni wa "kukhalapo" kwa zotsalira zomwe zimafunikira ndikuchotsa zoyipitsa zamtundu malinga ndi FDA yomwe ikuyesa mayeso otchedwa zovuta, zomwe ndizofunikira pakugwiritsa ntchito polyester yoyesedwa mu gawo la chakudya. Kuphatikiza pa kuvomereza kumeneku ndikofunikira kuti wogwiritsa ntchito njirayi azionetsetsa kuti malire a FDA azipangidwa ndi zinthu zomwe iye amapanga.

Kutembenuka mwachindunji kwa mabotolo oyikira

Kuti apulumutse ndalama, opanga ma polyester apakati akuwonjezerapo ngati mphero yoluka, ma mill, kapena ma mill filimu akugwiritsa ntchito mwachangu ma PET-flakes, pochotsa mabotolo ogwiritsa ntchito, ndi cholinga chopanga zochulukirapo kuchuluka kwa ma polyester apakatikati. Pofuna kusintha mamasukidwe ofunikira, kuphatikiza kuyanika kwa ma flakes, ndikofunikira kuti mupangitsenso mawonekedwe kuchuluka mu kusungunuka gawo kapena olimba boma boma kuchita. Njira zaposachedwa kusintha kwa PET flake zikugwiritsa ntchito mapangidwe awili amapasa, zowonjezera pamakina ambiri kapena kachitidwe kazungulira kambiri komanso zopangika mosabisalira pabwino kuti muchotse chinyontho ndi kupewa kuyimitsa. Njira izi zimalola kutembenuka kwa mapepala osatulutsidwa a PET popanda kuchepa kwakukulu kwa mawonekedwe am'mbuyo chifukwa cha hydrolysis.

Ponena za kumwa kwa flakes mabotolo a PET, gawo lalikulu la 70% limasinthidwa kukhala ulusi ndi mafayilo. Mukamagwiritsa ntchito zinthu zachiwiri monga mabulangete mu kupota, pali mfundo zingapo zomwe mungagwiritse ntchito.

Njira zothinirana kwambiri zomwe zimapangidwa kuti zikhale za POY nthawi zambiri zimafunikira mamasukidwe akayendedwe a 0.62-0.64 dℓ / g. Kuyambira kuchokera kumapeto a mabotolo, mamasukidwe akayendedwe amatha kukhazikitsidwa kudzera pakuwuma. Kugwiritsanso ntchito kwa TiO₂ ndikofunikira kuti ulusi wathunthu wosakhazikika kapena theka. Kuti muteteze ma spinnerets, kusefera koyenera kwa kosungunuka ndiko, mulimonse ndikofunikira. Pakutha kwa nthawi, kuchuluka kwa POY zopangidwa ndi polyester ya 100% kumakhala kotsika chifukwa njirayi imafunikira kuyera kwakukulu kwa kupindika kosungunuka. Nthawi zambiri, kuphatikiza kwa namwali ndi ma pellets okonzanso kumagwiritsidwa ntchito.

Ulusi wosunthika umalowerera m'malo amkatikati mwa intcinsic omwe amakhala otsika kwambiri ndipo amayenera kukhala pakati pa 0.58 ndi 0.62 dℓ / g. Pankhaniyi, nawonso, mawonekedwe oyenera amatha kusintha pang'onopang'ono pouma kapena phukusi popewa kutulutsa utupu. Pofuna kusintha mamasukidwe, kuphatikiza kwa kutalika kwa unyolo ngati ethylene glycol or Diethylene glycol itha kugwiritsidwanso ntchito.

Kuluka osaluka - mu gawo labwino kwambiri la nsalu zopangira zovala komanso kupota zinthu zazitali zomwe sizinapangidwe monga zida zoyambira, mwachitsanzo, zotenga padenga kapena zomanga msewu, zimatha kupangidwa ndi zikwangwani zopota. Maso otumphukira alinso m'malo a 0.58-0.65 dℓ / g.

Gawo limodzi lokhala ndi chidwi chochulukirapo pomwe zinthu zobwezerezedwanso zimagwiritsidwa ntchito ndikupanga mikwingwirima yayitali kwambiri, ndi ma monofilaments. M'magawo onse awiriwa, zida zoyambirira zophatikizidwazo ndizinthu zobwezerezedwanso zamphamvu kwambiri. Mikwingwirima yayikulu kwambiri komanso ma monofilament amapangidwa kuti azisungunuka.

Kubwezeretsanso kwa ochita ziphuphu

Polyethylene terephthalate akhoza kuchepetsedwa kuti apange opanga monomers. Pambuyo pakuyeretsa, ma monomers angagwiritsidwe ntchito kukonzekera polyethylene terephthalate yatsopano. Zingwe za ester mu polyethylene terephthalate zitha kupukutidwa ndi hydrolysis, kapena ndi transesterization. Zomwe zimachitika ndizosintha zomwe zidagwiritsidwa ntchito pakupanga.

Glycolysis pang'ono

Glycolysis yamtundu (transesterization ndi ethylene glycol) imatembenuza ma polima olimbikira kukhala oligomers okhala ndi manja ang'onoang'ono omwe amatha kusungunuka ndi kutentha pang'ono. Akamasulidwa ku zodetsa, ma oligine amatha kudyetsedwa kuti apange polima.

Ntchitoyi imakhala mukudyetsa 10-25% mabotolo poyimitsa mawonekedwe a mabotolo omwe amapangidwa pamzere. Cholingachi chimathetsedwa ndikuwononga mabotolo a PET omwe anali kale kale asanapange mapulasitiki, omwe angathe kuchitidwa kamodzi kapena kachulukidwe kakatundu kakang'ono kwambiri — ndikuwonetsa chidwi cha pafupifupi 0.30 dℓ / g powonjezera kachulukidwe ka ethylene glycol ndi poika mawonekedwe otsika a mamasukidwewo osungunuka kuti azitha kusefa mwachangu pambuyo pa kupulasitiki. Kuphatikiza apo, kutentha kumatengedwa kwambiri. Kuphatikiza apo, pogwiritsa ntchito njira iyi, kuthekera kwa kuwonongeka kwa mankhwala a hydro peroxides ndikotheka ndikuwonjezera P-stabilizer mwachindunji mukama pulasitiki. Kuwonongeka kwa magulu a hydro peroxide,, ndi njira zina, zimachitika kale mu gawo lomaliza la chithandizo cha flake mwachitsanzo powonjezera H₃PO₃. Zinthu zopangidwa ndi glycolyzed pang'ono komanso zosefera zobwezerezedwanso zimapatsidwa chakudya ku esterification kapena makina opangira ma preolycondensation, kuchuluka kwake kwa zinthuzo kumasinthidwa moyenera.

Glycolysis yathunthu, methanolysis, ndi hydrolysis

Chithandizo cha zinyalala za poliyesitala kudzera mu glycolysis yonse kuti mutembenuzire polyester kukhala bis (2-hydroxyethyl) terephthalate (C₆H₄(NKHA₂CH₂CH₂O)₂). Pulogalamuyi imayeretsedwa ndi vacuum distillation, ndipo ndi imodzi mwazomwe zimagwiritsidwa ntchito popanga polyester. Maganizo omwe akukhudzidwa ndi awa:

[(CO) C₆H₄(NKHA₂CH₂CH₂O)]_n + n HOCH₂CH₂OH → n C₆H₄(NKHA₂CH₂CH₂O)₂

Njira zobwezeretsazi zachitika pamalonda ku Japan ngati njira zoyesera.

Zofanana ndi glycolysis yathunthu, methanolysis amatembenuza polyester kukhala dimethyl terephthalate, womwe umatha kusefedwa ndikugaya utupu:

[(CO) C₆H₄(NKHA₂CH₂CH₂O)]_n + 2n CH₃OH → n C₆H₄(NKHA₂CH₃)₂

Methanolysis sichimachitika kawirikawiri m'makampani masiku ano chifukwa kupanga kwa polyester kutengera dimethyl terephthalate kwayamba kugwa kwambiri, ndipo ambiri opanga dimethyl terephthalate asowa.

Komanso monga pamwambapa, polyethylene terephthalate akhoza hydrolyzed kuti terephthalic acid ndi ethylene glycol pansi pa kutentha kwakukulu ndi kupanikizika. Zotsatira zake za terephthalic acid zimatha kuyeretsedwa ndi kubwezeretsanso kupereka zinthu zoyenera kukonzanso polima:

[(CO) C₆H₄(NKHA₂CH₂CH₂O)]_n + 2n H₂O → n C₆H₄(NKHA₂H)₂ + n HOCH₂CH₂OH

Njirayi sikuwoneka kuti yayamba kugulitsidwa.