Ukulinganisa uxinano ngexesha langempela yinto entsha ebalulekileyo kwinkqubo yokuvelisa iplastiki ebolayo. Iimitha zoxinano ezingaphakathi kweLonnmeter zilinganisa uxinano lwepropylene yolwelo kunye ne-slurries ngokufundwa okuqhubekayo nokuchanekileyo. Olu hlolo lwangoku lwangempela lwenza abaqhubi bakwazi ukuphendula ngoko nangoko kwiimpazamo, ukulungisa amazinga okutya okanye iimeko zenkqubo ukugcina i-polymerization ingaphakathi kweenkcukacha.
ISISHWANKATHELO sebhunga
Inkqubo yokwenziwa kweplastiki ebolayo imele isisombululo esibalulekileyo kwingxaki ekhulayo yongcoliseko lokusingqongileyo olubangelwa ziiplastiki ezisekelwe kwipetroliyam ezihlala zihleli. Ijolise kwimveliso ezinzileyo ngokuguqula izixhobo ezivuselelekayo, ezifana ne-lignin evela kushishino lwe-pulp nephepha, zibe zii-polymers ezinobuhlobo nokusingqongileyo ezineempawu zobunjineli kunye namazinga okuwohloka alawulwayo. Eli candelo libandakanya amanqanaba aliqela aphambili, ukusuka ekukhetheni izinto eziluhlaza kunye nokuguqulwa kweekhemikhali, ngokusebenzisa iindlela eziphambili ze-polymerization, ukuya ekuguqulweni zibe ziimpahla ezigqityiweyo ngokusebenzisa iindlela ezikhethekileyo zokubumba.
Iplastiki Ebolayo
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Eyona nto iphambili kwinkqubo yokuvelisa iplastiki ebolayo ikwiindlela ezimbini eziphambili ze-polymerization: i-condensation polymerization kunye ne-ring-opening polymerization (ROP). Ezi zivumela ulawulo oluchanekileyo phezu kobunzima be-molecular kunye nesakhiwo sezinto, ezibalulekileyo ekulungiseleleni i-biodegradation kunye nokusebenza koomatshini. Uyilo olutsha lwakutshanje lugxile ngokukodwa ekudibaniseni i-lignin kwi-polyester matrices, kusetyenziswa i-graft-onto kunye ne-graft-from copolymerization ukuphucula amandla okutsalwa kunye nokuqhekeka kokuphela kobomi. Ukwenziwa kwenkqubo yokuhamba okusekwe kwi-microreactor kuseta umgangatho omtsha wokusebenza kakuhle. Ngokungafaniyo neendlela zendabuko ze-batch, ii-microreactors zibonelela ngolawulo olukhethekileyo lobushushu kunye nokuxuba, zinyusa isantya se-polymerization ngelixa zinciphisa ukusetyenziswa kwamandla, kwaye zisusa ii-catalysts zesinyithi ezinobuthi ukuze kusetyenziswe ezinye iindlela ezinobuhlobo nokusingqongileyo. Isiphumo sisiphumo esihambelanayo see-polymers ezinobunye obuphuculweyo kunye nempembelelo encinci kwindalo esingqongileyo.
Ubunzima obuphambili ekuphuculeni inkqubo yokwenziwa kweplastiki ebolayo buvela ekuguquleni impumelelo yelabhoratri ibe yimveliso ethembekileyo nenkulu. Ukwamkelwa kwemizi-mveliso kuxhomekeke kulawulo lomgangatho oluqinileyo nolwexesha langempela. Umngeni omnye oqhubekayo kukuqinisekisa ukusasazwa kobunzima beemolekyuli obufanayo kuyo yonke imisebenzi yemveliso, okubalulekileyo ekuqikeleleni ukusebenza kunye nokuvunywa komthetho. Ngokufanayo, iipropati zoomatshini kunye nezobushushu kufuneka zihambelane neemfuno ezingqongqo zokupakisha, iimpahla zabathengi, kunye neefilimu zezolimo.
Ukubeka iliso kwi-polymerization kunye nokulawula inkqubo yokwenza iplastiki ebolayo iye yaphucuka ngezixhobo zokulinganisa ngokuchanekileyo. Iimitha zoxinano oluphakathi kunye ne-viscosity, ezifana nezo zenziwe yiLonnmeter, zidlala indima ebalulekileyo ekubekeni iliso ngexesha langempela ngexesha le-propylene slurry okanye i-bulk polymerizations. Ezi zixhobo zivumela ukulinganiswa okuqhubekayo koxinano lwe-propylene kunye ne-viscosity yolwelo, okuvumela ukulungiswa kwangoko kweeparamitha zokufaka. Ukubeka iliso kwi-propylene density ngexesha langempela kunceda ekugcineni ukuhambelana kwebhetshi, ukuphucula ukusetyenziswa kwe-catalyst, kunye nokuqinisekisa iipropati ezijoliswe kuzo ze-polymer—isitshixo sokunciphisa inkunkuma kunye nokugqithiswa kweendleko ngelixa kuhlangatyezwana neethagethi zozinzo. Iimitha zoxinano oluchanekileyo lwe-propylene zikwaxhasa ukwenziwa kweenkqubo kunye namaxwebhu afunekayo ukuze kuthotyelwe imithetho kwiindlela zokwenziwa kweplastiki ebolayo ezisetyenziswa lishishini.
Nangona kukho impumelelo ephawulekayo, ukukhulisa inkqubo yeplastiki ebolayo kuyaqhubeka nokuhlangabezana nemiqobo. Ubonelelo lwezondlo ezisemgangathweni ezisekelwe kwibhayoloji, ukuhlanganiswa kwekhemistri eluhlaza kwinqanaba ngalinye, kunye nesidingo sokuphucula iindlela zokuvavanya nokubeka iliso kufuna ingqwalaselo eqhubekayo. Ukukhetha iindlela ezifanelekileyo zokubumba iplastiki ebolayo kunye neenkqubo zokujova kufuneka kuqinisekise kungekuphela nje ukusebenza kokusetyenziswa, kodwa kunye nokuphazamiseka kokuphela kobomi kwiindawo zokwenyani—ithagethi isaphuculwa ngenkxaso evela kubuchwepheshe bovavanyo nokubeka iliso obuphuculweyo.
Ngamafutshane, izinto ezintsha kwi-polymerization yokuhamba rhoqo, ukusetyenziswa ngobuchule kwe-lignin kunye nezinto ezivuselelekayo, kunye nolawulo loxinano lwe-slurry ngexesha langempela lubonisa imeko-bume eguqukayo yokwenziwa kweplastiki enobuhlobo nokusingqongileyo. Ukudibana kwezi nkqubela phambili kuxhasa inkqubela phambili yeli candelo ekuveliseni iiplastiki ezinokonga imali, ezisebenza kakuhle, nezizinzileyo ngokwenene.
Iiplastiki Ezibolayo Nendima Yazo Kwimveliso Yanamhlanje
Iiplastiki ezinokubola zizinto ezenziwe ngepolymeric ezenzelwe ukubola ngesenzo sebhayoloji—oko kukuthi, imetabolism yezinto ezincinci ezifana neebhaktheriya, iifungi, okanye i-algae. Oku konakala kuvelisa iimveliso zokugcina ezingalunganga kwindalo ezifana namanzi, i-carbon dioxide, i-methane (phantsi kweemeko ze-anaerobic), kunye ne-biomass. Ngokungafaniyo neepolymers eziqhelekileyo, ezithathwe kwiikhemikhali ze-petrochemicals kwaye zimelana nokubola kwendalo, iiplastiki ezinokubola ziqulathe unxibelelwano lweekhemikhali olusengozini yokuqhekeka kweentsholongwane kunye ne-enzymatic, kunye ne-hydrolysis.
Umahluko phakathi kweeplastiki ezibolayo kunye neepolymers eziqhelekileyo usekelwe kuyilo lwazo lweekhemikhali. Iiplastiki eziqhelekileyo, ezifana ne-polyethylene (PE) kunye ne-polypropylene (PP), zine-backbones eqinileyo ye-carbon-carbon ene-crystallinity ephezulu kunye ne-hydrophobicity, nto leyo eyenza ukuba zihlale ixesha elide kwaye zingaboli. Ezi zinto zihlala kwindawo engqongileyo amashumi eminyaka okanye ngaphezulu, ziqhekeka kuphela ngokubola kancinci kwe-photo okanye i-thermal oxidation engayinciphisi kakhulu impembelelo yazo kwindalo. Ngokwahlukileyo koko, iipolymers ezibolayo zihlala zine-hydrolyzable ester, amide, okanye ii-glycosidic bonds kwi-backbone yazo, zikhawulezisa kakhulu ukubola xa zichatshazelwa zizinto ezifanelekileyo kwindalo kunye ne-biological. Umzekelo, i-polylactic acid (PLA) kunye ne-polyhydroxyalkanoates (PHA) zifaka ezo bonds ziqhekekayo, zivumela ukuqhekeka nge-hydrolysis kunye ne-microbial enzyme action.
Iiplastiki ezibolayo zingahlulwahlulwa ngokwekhemikhali yazo kunye nezinto eziluhlaza. I-PLA yenye yezona zibalulekileyo kwezorhwebo, iveliswa ngokubiliswa kwezinto ezivuselelekayo ezifana nesitatshi sombona okanye umoba. Ulwakhiwo lwayo, i-polyester ethe tyaba edityaniswe zii-ester bonds, ithanda ukubola kwe-hydrolytic—nangona ikakhulu phantsi kwamaqondo obushushu aphezulu kunye nokufuma okuqhelekileyo kwe-compost yemizi-mveliso. I-PHA, eveliswa ziintsholongwane ezivela kwiintlobo ngeentlobo ze-organic feedstocks ezifana ne-oyile yemifuno okanye i-starches, inesakhiwo esifanayo se-polyester kodwa inikezela ukubola ngokukhawuleza kwiindawo zomhlaba nasemanzini. I-Polybutylene succinate (PBS) kunye ne-poly(butylene adipate-co-terephthalate) (PBAT) nazo zii-polyester eziphambili ezibolayo; I-PBS idla ngokuvela kwi-succinic acid kunye ne-butanediol evela kwii-feedstocks zezityalo, ngelixa i-PBAT yi-co-polyester edibanisa iiyunithi ezibolayo kunye ne-aromatic ukulungisa iipropati ze-mechanical kunye ne-degradation kinetics.
Iiplastiki ezisekelwe kwisitatshi zisetyenziswa kakhulu, zenziwe ngokudibanisa istatshi sendalo—ikakhulu esiquke i-amylose kunye ne-amylopectin polysaccharides—kunye nezinye iipolymers ezinokubola okanye eziqhelekileyo ukuze kuphuculwe ukusebenza kunye nokucutshungulwa kwazo. Ukuqhekeka kwazo kuxhomekeke kwii-enzymes ze-microbial eziqhawula ii-glycosidic bonds, nto leyo ekhokelela ekonakaleni kokusingqongileyo ngokukhawuleza phantsi kweemeko ezifanelekileyo.
Ukutshintshela kwiiplastiki ezinokubola kwimveliso kunika iingenelo ezininzi zokusingqongileyo nezokusebenza. Okokuqala, ezi zinto zinciphisa umthwalo wenkunkuma yeplastiki oqhubekayo, njengoko iimveliso zazo zokubola zidityaniswa ngakumbi yimijikelo yendalo ye-biogeochemical. Oku kubaluleke ngakumbi njengoko uxinzelelo lwehlabathi kunye nolwentlalo lusanda ukujongana nongcoliseko lweplastiki kunye neeplastiki ezincinci. Ukongeza, iiplastiki ezininzi ezinokubola zisebenzisa izitokhwe zokutya ezivuselelekayo, ezinokunciphisa ukukhutshwa kwegesi ezigcina ubushushu kwaye zinciphise ukuxhomekeka kwimithombo yefosili ephelileyo.
Ngokwembono yokucubungula, iiplastiki ezinokubola ziyasebenziseka kwaye ziyahambelana neendlela ezisetyenzisiweyo zokwenza ipolymer, ezifana nokubumba ngenaliti kunye nokukhutshelwa ngaphandle. Iindlela ezifana nokubumba ngenaliti yeplastiki ezinokubola kunye nezinye iinkqubo zokubumba ngokuyintloko zilungelelaniswa nokucubungula i-thermoplastic eqhelekileyo, okuvumela ukuhlanganiswa okulula kwiziseko ezikhoyo zokupakisha, ezolimo, kunye nezinto ezisetyenziswa kanye.
Ngokwasemsebenzini, ulawulo lomgangatho wexesha langempela ekuvelisweni kweeplastiki ezinokubola kubalulekile, ngakumbi xa kusetyenziswa izitya zokutya ezisekelwe kwi-bio-based kunye neziguquguqukayo. Izixhobo zokulinganisa ezikwi-inline, ezifana neemitha zoxinano ezivela eLonnmeter, zenza kube lula ukulinganisa i-propylene density real-time measurement kunye nolawulo lwe-propylene slurry polymerization. Ukubeka esweni ngokuchanekileyo iiparameter eziphambili ezifana ne-liquid propylene density kunye neemeko zenkqubo ye-polymerization kuqinisekisa umgangatho we-polymer ohambelanayo, ukusebenza kakuhle koomatshini, kunye namazinga okubola okuqikelelweyo. Olu hlobo lolawulo lwenkqubo luyinxalenye ebalulekileyo yemveliso ye-polymer yanamhlanje ebolayo, ikhusela zombini iipropati zezinto kunye nokuthobela imigangatho yokusebenza okanye yokwenziwa komgquba.
Izifundo zendalo kwiminyaka emibini edlulileyo zibonisa ukuqonda okubalulekileyo: isantya sokwenyani kunye nokuphelela kokubola kwezinto eziphilayo kuxhomekeke kungekuphela nje kwisakhiwo sepolymer kodwa nakwimeko yendalo. Umzekelo, i-PLA ifuna amaqondo obushushu okwenziwa komgquba kwimizi-mveliso ukuze kuqhekeke ngokukhawuleza, ngelixa i-PHA kunye neeplastiki ezithile ezisekelwe kwisitatshi zibola ngokukhawuleza kumhlaba wendalo okanye kwiimeko zaselwandle. Iingenelo zokwenyani zendalo zinxulunyaniswa nokukhethwa kwekhemistri yepolymer efanelekileyo kunye nokusekwa kweziseko zokuxhasa ulawulo lwenkunkuma.
Ukwamkelwa kweeplastiki ezinokubola kuvula amathuba amatsha oyilo lwemveliso oluzinzileyo kunye neendlela zokugqibela ezinoxanduva, ingakumbi xa zidityaniswe nokubeka esweni inkqubo ngokungqongqo, ukusetyenziswa kakuhle kwempahla yokutya, kunye nokukhetha izinto ezinolwazi. Ukuhlanganiswa kwazo ngempumelelo kwimveliso yanamhlanje kuxhomekeke ekuqondeni ngokupheleleyo ikhemistri yazo kunye nenkqubo yokwenziwa kweplastiki ezinokubola, kunye nolawulo olunoxanduva kuyo yonke imigangatho yemveliso, ukusetyenziswa, kunye nokulahla.
Ukukhethwa kunye nokulungiswa kwezinto eziluhlaza
Ukukhethwa kokutya okuzinzileyo nokuhlaziyekayo sisiseko senkqubo yokwenziwa kweplastiki ebolayo. Le migaqo ifuna uvavanyo oluqinileyo lomjikelo wobomi (i-LCA) ukuqinisekisa ukukhutshwa kwegesi ezibangela ubushushu obuphantsi, ukusetyenziswa komhlaba namanzi okuncitshisiweyo, kunye nokubola kwe-biodegradation okusebenzayo ekupheleni kobomi. Ii-LCA zanamhlanje zijongana nokulima, ukuvuna, ukucubungula, kunye nemiphumo engezantsi, ukuqinisekisa ukuba ukufumana izinto ezifana neentsalela zezolimo, i-biomass engatyiwayo, okanye inkunkuma yendalo kunika iingenelo ezibonakalayo zokusingqongileyo.
Iimpahla zokutya maziphephe ukukhuphisana nokutya. Izinto ezifana ne-switchgrass, i-miscanthus, ii-crop husks, i-waste cooking oil, okanye i-textile waste-derived cellulose zikhethwa kakhulu. Ezi azikhuthazi nje kuphela iindlela zoqoqosho olujikelezayo kodwa zinciphisa kakhulu impembelelo yokusingqongileyo kunye neendleko zezinto eziluhlaza xa kuthelekiswa nombona okanye umoba. Abavelisi kufuneka baqinisekise ukuba ukukhethwa kwezityalo kunye nokwanda kwemfuno akubangeli utshintsho olungathanga ngqo ekusetyenzisweni komhlaba, njengokugawulwa kwamahlathi okanye ukulahleka kwezinto eziphilayo. Ukulandelela, kunye namaxwebhu ukusuka kumthombo ukuya kwi-polymerization, kuye kwaba yimfuneko eqhelekileyo kubathengi kunye nabalawuli ukuqinisekisa uxanduva lweenkonzo zokubonelela.
Imveliso yeplastiki ebolayo ikwabandakanya uzinzo lwentlalo noqoqosho njengemilinganiselo ebalulekileyo yokukhetha. Iimpahla ezisetyenzisiweyo kufuneka zifumane ubungqina obuqinisekisiweyo beemeko zokusebenza ezifanelekileyo kunye neenzuzo kuluntu lwasekuhlaleni. Iinkqubo zokuzithandela kunye nokuhlolwa kwamaqela esithathu zihlala zifuneka ngaphambi kokuba kuvunywe.
Ukuhlaziywa ngokukhawuleza kubalulekile. Izityalo zonyaka, iimveliso eziphuma kwezolimo, kunye nezinto ezizalisa ngokukhawuleza ezifana ne-algae okanye ingca ziya ziqheleka ngenxa yamanqanaba azo okuhlaziya ngokukhawuleza kunye nemingcipheko embalwa yokuphazamiseka kwenkqubo yendalo. Ukutya kufuneka kukhuliswe kwaye kucutshungulwe ngekhemikhali encinci enobungozi; ukusetyenziswa kwezibulali-zinambuzane kunye nokusetyenziswa kongcoliseko oluqhubekayo lwendalo kuthintelwe kakhulu, kunye notshintsho olukhulayo oluya ekulimeni kwendalo kunye nolawulo oludibeneyo lwezinambuzane.
Ukubeka phambili inkunkuma kunye nemithombo engaphantsi kwemveliso kulungelelanisa inkqubo yokwenziwa kweplastiki ebolayo kunye neenkqubo ezibanzi zokwenziwa kweplastiki ezinobuhlobo nokusingqongileyo. Oku kubandakanya ukusebenzisa iimveliso ezingaphantsi kwemveliso emva koshishino okanye emva komthengi, ukuqhuba ukusebenza kakuhle kwezixhobo, kunye nokuxhasa uqoqosho olujikelezayo.
Emva kokukhetha, amanyathelo angaphambi kokucubungula abalulekile ukuze kuphuculwe ukukhutshwa kwe-monomer kunye nobunyulu. Iintsalela zezolimo, umzekelo, zifuna ukugaywa, ukomiswa, kunye nokuqhekezwa ngaphambi kokuba i-hydrolysis ivelise iiswekile ezinokubila. Izityalo ezityebileyo kwisitatshi ziphantsi konyango lokusila kunye ne-enzyme ukuze kuqhekeke iicarbohydrate ezintsonkothileyo. Kwi-feedstocks ze-cellulose, i-chemical okanye i-mechanical pulping isusa i-lignin kwaye iphucule ukuqhubekeka kokusebenza. Inyathelo ngalinye lijolise ekukhutshweni okuphezulu kwee-monomers ezisebenzisekayo njenge-lactic acid, ebalulekileyo kwiindlela zokwenziwa kweplastiki ezinokubola kunye neenkqubo ze-polymerization zeplastiki ezisezantsi.
Izitokhwe zokutya ezilungisiweyo kwangaphambili zijongwa ngokungqongqo ukwakheka kwazo, umxholo ongcolisayo, kunye nokufuma. Oku kuqinisekisa umgangatho wokufaka ohambelanayo kunye nokusebenza okuthembekileyo kumanyathelo alandelayo okuguqula iikhemikhali okanye ukubila—okuchaphazela ngokuthe ngqo uzinzo lwenkqubo, isivuno sempendulo, kunye nokukhula ngokubanzi kokwenziwa kweplastiki ebolayo. Ukulungiswa kwezitokhwe zokutya ngoko ke akupheleli nje kwimfuneko yokusingqongileyo; kubalulekile ekugcineni ukusebenza kakuhle kunye nokuveliswa kwazo zonke izigaba zenkqubo ezisezantsi.
Ukubumba nokuBumba: Ukusuka kwiikhompawundi ukuya kwiimpahla ezigqityiweyo
Ukubumba Inaliti yePlastiki eBolayo
Ukubumba i-injection yeplastiki ebolayo kuxhomekeke ekuhanjisweni ngokuchanekileyo kwee-resin ezinyibilikisiweyo—ezifana ne-PLA, i-PHA, kunye ne-PBS—kwindawo enomngxuma, apho izinto zipholile khona kwaye zithathe i-geometry yokugqibela. Le nkqubo ifuna ingqalelo engqongqo kwinkqubo yokwenziwa kweplastiki ebolayo kwaye ibandakanya iindlela ezithile ezilungileyo ngenxa yobuthathaka beekhemikhali kunye nobushushu bezi zinto.
Iimold zePolylactic acid (PLA) ziphakathi kwe-160 kunye ne-200 °C, kodwa iziphumo ezilungileyo zenzeka kwi-170–185 °C. Ukudlula la maqondo obushushu kunokubangela uqhekeko lwetsheyini, ukulahleka kobunzima bemolekyuli, kunye nokuhla kokusebenza koomatshini. Ubushushu bemold buhlala buphakathi kwe-25 kunye ne-60 °C. Amaqondo obushushu aphezulu emold, ukusuka kwi-40 ukuya kwi-60 °C, anyusa ubukristali kwaye aphucula amandla oomatshini, ngelixa ukupholisa ngokukhawuleza ngaphantsi kwe-25 °C kunokubangela uxinzelelo lwangaphakathi kunye nokwakheka kwekristale okungalunganga. Uxinzelelo lwe-injection luhlala luqala kwi-60 ukuya kwi-120 MPa—okwaneleyo ukuqinisekisa ukuzaliswa kwemold ngelixa kuthintelwa ukukhanya. I-viscosity ephantsi ye-PLA ivumela isantya esiphakathi, kuthintelwe iingozi zokucheba okuphezulu okonakalisa i-polymer. Okubaluleke kakhulu, i-PLA kufuneka yomiswe ngokufanelekileyo ngaphantsi kwe-200 ppm ukufuma (iiyure ezi-2–4 kwi-80–100 °C). Nasiphi na isixa samanzi esigqithisileyo sibangela ukubola kwe-hydrolytic, okubangela ukuba iindawo ezibuthathaka nezingasebenzi kakuhle.
Iiresini ze-PHA, ezifana ne-PHB kunye ne-PHBV, zinemfuno ezifanayo zokulungiswa kobushushu obulawulwayo. Zibuna kakuhle phakathi kwe-160 kunye ne-180 °C. Kumaqondo obushushu angaphezu kwe-200 °C, ii-PHA ziwohloka ngokukhawuleza. Abaprosesa kufuneka basebenzise amaqondo obushushu obunokubunjwa phakathi kwe-30 kunye ne-60 °C. Uxinzelelo lwe-injection luhlala luqala kwi-80 ukuya kwi-130 MPa kwaye luxhomekeke kulwakhiwo lwe-copolymer kunye nomxube. Njenge-PLA, ii-PHA zinobuthathaka kakhulu kumanzi aseleyo kwaye zifuna ukomiswa kwi-60–80 °C kumanqanaba okufuma angaphantsi kwe-500 ppm. Isantya esicothayo se-injection sinciphisa ukubola kwe-shear, sigcina ukuthembeka kwetyathanga le-polymer.
Ii-resin ze-PBS, nangona ziqinile kubushushu kune-PLA okanye i-PHA, zisafuna ukunyibilika phakathi kwe-120 kunye ne-140 °C. Ukucutshungulwa kumaqondo obushushu aphezulu (> 160 °C) kunokonakalisa i-matrix. Amaqondo obushushu obungu-20–40 °C aqhelekile; amaqondo obushushu aphezulu anceda ukwakheka kwekristale, okuphucula uzinzo lobukhulu bento ebunjiweyo. Uluhlu loxinzelelo oluqhelekileyo yi-80–100 MPa. I-PBS inokunyamezela ukufuma okuphezulu kokuqala kune-PLA, kodwa kufuneka isabekwe kwi-80 °C ngaphambi kokubumba.
Izinto ezikhethekileyo ekufuneka ziqwalaselwe xa kulungiswa ezi zinto ziquka ubuthathaka kwixesha lokuhlala kunye nokufunxwa komswakama. Ixesha elide kwibhareli okanye kwisikhunta kumaqondo obushushu aphezulu likhawulezisa ukuwohloka, lidala iziphene ezifana nokutshintsha kombala, ukuqhekeka, kunye nevumba. Ulawulo olufanelekileyo lokufuma, olufezekiswa ngokumisa kwangaphambili, lubalulekile kuyo yonke inyathelo lenkqubo yokwenza iplastiki ebolayo. Izixhobo zokujonga ixesha langempela, ezifana neemitha zoxinano oluphakathi kunye neemitha zoxinano oluphakathi ezenziwe yiLonnmeter, zinceda ukugcina ukuhambelana kwezinto ngokutyhila ukuphambuka kwiimpawu zokunyibilika ngenxa yokuguquguquka kobushushu okanye kokufuma.
Iziphene eziqhelekileyo zokubumba kwiiresini ezinokubola ziquka ukubola (okuvela kumswakama ogqithisileyo), ukwaphuka okubuthathaka (okubangelwa kukoma kakhulu okanye ubushushu obuphezulu kakhulu), kunye nokungagcwali ngokupheleleyo (okuvela kubushushu obuphantsi bokubumba okanye uxinzelelo oluphantsi). Ukuba kuvela ukubola, sebenzisa ukomisa okungqongqo ngakumbi. Ukuba kuvela imifantu okanye ukubola, nciphisa ubushushu bokunyibilika kwaye unciphise ixesha lokuhlala. Ukubola kudla ngokuphendula kuxinzelelo oluphezulu lwe-injection okanye ukunyuka okuncinci kobushushu bokunyibilika.
Izifundo zibonisa ukuba ukuphucula amaqondo obushushu bokubumba kukhokelela ekuphuculweni kweempawu zoomatshini nezomphezulu ze-PLA kunye ne-PBS, ngelixa ukunciphisa ixesha lokuhlala elinyibilikisiweyo kugcina ubunzima bemolekyuli yeeresini ze-PHA. Amaxesha omjikelo, iiparameter zokomisa, kunye nokubeka iliso kwinkqubo kusabalulekile kwimveliso engenaziphene yeendawo zeplastiki ezinokubola.
Ezinye iindlela zokuguqula
Ngaphaya kokubumba ngenaliti, iindlela ezininzi zibalulekile kumanyathelo okuvelisa izinto zeplastiki ezinokubola, nganye ilungiselelwe ukusebenza okuthile kunye neemfuno zokwenziwa komgquba.
Ukukhupha iplastiki kuyila iplastiki ngokunyanzela i-polymer enyibilikisiweyo kwidayi, yenze iiprofayili, iityhubhu, kunye namaphepha. Kwinkqubo yeplastiki ebolayo, ukukhupha iplastiki kuvelisa amaphepha e-PLA e-thermoforming okanye ii-pellets ze-PBS ukuze zisetyenziswe kamva. Isitshixo somgangatho kukuxinana okunyibilikayo okufanayo, okujongwa ngeemitha zoxinano zexesha langempela ezifana nezo zivela eLonnmeter, ukuqinisekisa ukuhamba komoya kunye nobukhulu bodonga obuhambelanayo.
Ukuvuthuza ifilimu kwenza iifilimu ezincinci ezinokubola (zeengxowa okanye zokupakisha) ngokukhupha i-resin ngedayi ejikelezayo nokuyikhulisa ibe yibhamuza. Ukulawula ubushushu kunye nesantya sokuhamba kwamanzi apha kubalulekile ukuze kubekho ubukhulu obulinganayo kunye nokuqina koomatshini, ingakumbi kuba ii-resin ezinokubola zihlala zibuthathaka kutshintsho lomswakama kunye nobushushu.
I-thermoforming ifudumeza amaphepha eeplastiki ezinokubola—ngokuqhelekileyo i-PLA—ide iguquguquke, ize iwacinezele kwiimolds ukuze yenze itreyi, ikomityi, okanye iimilo zesiciko. Ukulungiswa ngempumelelo kuxhomekeke kubukhulu bephepha elifanayo kunye nokomiswa kwangaphambili kweefilimu zokufaka ukuthintela amaqamza angaphakathi kunye namabala abuthathaka.
Ukubumba ngokuvuthuza kudala izinto ezingenanto ezifana neebhotile kunye nezikhongozeli. Kwiiplastiki ezibolayo ezifana ne-PBS, ulawulo olucokisekileyo lwamandla okunyibilika kunye nobushushu be-parison (preform) lubalulekile kuba ezi zinto zinokuba buthathaka ngakumbi ekuweni nasekungalinganini ngexesha lokuvuthuza.
Indlela nganye yokuguqula kufuneka ihambelane ne-resin kunye nemveliso oyifunayo. Ukuze kubekho umgquba ophezulu kunye nokusebenza kakuhle, khetha inkqubo ehambelana neemfuno zobushushu, zoomatshini, kunye ne-crystallization ze-polymer kunye ne-geometry yenxalenye yokugqibela kunye ne-use-case. Ukusebenzisa ukujonga uxinano kwi-intanethi ngexesha langempela ngexesha lokukhupha, ishidi, okanye imveliso yebhotile kuqinisekisa ukuhambelana kwemveliso kwaye kunciphisa inkunkuma.
Ukulungelelanisa ngokufanelekileyo inkqubo nemveliso—nokuba kungokusebenzisa i-plastic injection molding, i-extrusion, i-film blowing, i-thermoforming, okanye i-blow molding—kuqinisekisa ukuba iindlela zokuvelisa iplastiki ebolileyo ziyahlangabezana nolindelo lokusingqongileyo kunye nomgangatho. Yonke indlela kufuneka ithathele ingqalelo ngokufanelekileyo uvakalelo olulodwa lwe-biopolymer, kunye nokubeka esweni, ukomisa, kunye nolawulo lobushushu olufakwe kwinkqubo yokwenziwa kweplastiki ebolileyo.
Ukuphucula Inkqubo: Ukubeka esweni nokulawula iiPropathi zePolymer
Ulawulo oluqinileyo lwenkqubo lubalulekile kwinkqubo yokwenziwa kweplastiki ebolayo, nto leyo elawula iipropati zokugqibela zepolymer ezifana namandla oomatshini, ukubola kwayo, kunye nokhuseleko. Ukufezekisa ukubola kwayo kunye nokudibanisa kakuhle kuthetha ukulawula ngokusondeleyo iiparameter eziphambili: ubushushu, uxinzelelo, ixesha lokuphendula, kunye nobunyulu bazo zonke izinto ezifakwayo.
Ubushushu kufuneka bulawulwe ngokuchanekileyo. Ukuphambuka kunokutshintsha ubunzima bemolekyuli yepolymer, ubukrelekrele, kunye nokusebenza kwayo. Ubushushu obugqithisileyo bunokubangela ukuqhekeka kwetyathanga okanye ukonakala kweemonomers ezinobuthathaka, nto leyo ebangela iiplastiki ezibuthathaka okanye ezingaguqukiyo ezibolayo. Ngokwahlukileyo koko, amaqondo obushushu aphantsi kakhulu athintela ukuguqulwa kwemonomer, nto leyo efuna amaxesha okusabela amade angasebenzi kakuhle kwaye ibeka emngciphekweni iimpendulo ezingaphelelanga.
Impembelelo yoxinzelelo ibonakala kwiinkqubo ezisebenzisa ii-monomers eziguquguqukayo okanye ii-gas-phase polymerizations, njengakwi-propylene polymerization. Uxinzelelo oluphezulu lunokunyusa amazinga okuphendula kunye nobunzima beemolekyuli zepolymer, kodwa uxinzelelo olugqithisileyo lunyusa umngcipheko wokungaphumeleli kwezixhobo kunye neempendulo ezingafunekiyo. Kwezinye iinkqubo, ezifana ne-polycondensation, uxinzelelo olungaphantsi komoya lunceda ukususa iimveliso ezingasemva kwaye luqhubele phambili impendulo ekugqibeleni.
Inyathelo ngalinye kwinkqubo yokwenza iplastiki ebolayo lixhomekeke kakhulu kubunyulu obupheleleyo bee-monomers, ii-catalysts, kunye nezinyibilikisi. Nokuba umswakama omncinci okanye izinto ezingcolisayo zesinyithi zinokubangela iziphumo ebezingalindelekanga, ziqalise ukupheliswa kwetyathanga ngaphambi kwexesha, okanye ii-catalysts ezinetyhefu. Iinkqubo zoshishino ziquka ukucocwa okungqongqo kwezinto ezifakwayo kunye nokucoca ngononophelo zonke izixhobo zenkqubo ukukhusela imveliso ehambelanayo nesemgangathweni ophezulu.
Uxinano lwe-slurry luphawu olubalulekileyo, ngakumbi kwi-propylene polymerization—indlela eqhelekileyo ekuveliseni ii-resin ze-polymer ezinokubola. Ukugcina uxinano olufanelekileyo kwi-slurry ye-polymerization kuchaphazela ngokuthe ngqo i-reaction kinetics kwaye, ekugqibeleni, iimpawu zezinto.
Inzuzo yokulinganisa kwi-intanethi, ngexesha langempela kunyeimitha yoxinano lwepropylenekubini. Okokuqala, abaqhubi banokufikelela kumgangatho ozinzileyo wemveliso ngokusebenzisa idatha engaphazanyiswayo kwiuxinano lwepropylene yolweloOkwesibini, ukubonwa kwangoko kokuguquguquka koxinano kuvumela ukulungiswa ngexesha elifanelekileyo—ukuthintela ukuveliswa kweebhetshi ezingaqhelekanga okanye ezilahlekileyo. Impendulo enjalo yenkqubo ethe ngqo ibalulekile ekugcineni umgangatho ofanayo wepolymer, ngakumbi kwimigca yokuvelisa eqhubekayo nevelisayo.
Ukudibanisa iimitha zoxinano ezifana nezo zenziwe yiLonnmeter kwi-polymerization reactor okanye i-compounding extruder kubonelela ngesixhobo esinamandla sokwenza ngcono inkqubo rhoqo. Ngokulandela iindlela zoxinano kuyo yonke imveliso, abavelisi banokuhlalutya ngokweenkcukacha inkqubo, babeke ii-alamu zenkqubo ezichanekileyo, kwaye basebenzise amaqhinga olawulo acwangcisiweyo. Oku kunciphisa inkunkuma yezinto eziluhlaza, kwandisa imveliso, kwaye kuxhasa ngokuthe ngqo iinjongo zeenkqubo zokwenziwa kweplastiki ezinobuhlobo nokusingqongileyo.
Iinkqubo zokubeka esweni uxinano lwepropylene ngexesha langempela zinempembelelo eqinisekisiweyo. Xa uxinano lwepropylene yolwelo lulawulwa ngokuqinileyo, ukuhambelana kweresin kuyaphucuka kwaye ukuphazamiseka kwenkqubo kuyancitshiswa. Impendulo ekhawulezileyo evela kwiimitha zoxinano ithetha ukuba iinjineli zenkqubo zinokuphepha ukudubula iithagethi ngokugqithisileyo, ukunciphisa ukuguquguquka kunye nokusetyenziswa okugqithisileyo kwamandla kunye nezinto eziluhlaza. Ezi zicwangciso zolawulo ngoku zithathwa njengeyona ndlela ilungileyo yokwenza izinto zeplastiki ezinokubola kunye nemigca edibeneyo yanamhlanje.
Ukuhlanganiswa kwezi zixhobo zexesha langempela kuxhasa ukuphuculwa okuqhubekayo kwamanyathelo okuvelisa iplastiki ebolayo, nto leyo evelisa iindlela zokuziphatha eziphinda ziveliseke ngoomatshini, ngobushushu, nangokwezinto ezibolayo kwiindawo zemveliso. Olu lawulo luchanekileyo luyimfuneko njengoko imigangatho yokulawula, yokhuseleko, kunye neyemarike yeepolymers ezibolayo iqhubeka iqina.
Imingeni ekuphuhliseni imveliso yeplastiki ebolayo
Ukwenziwa kwenkqubo yokwenziwa kweeplastiki ezibolayo kwimizi-mveliso kujongana nemiqobo ebanzi yexabiso, iqala ngexabiso lokutya kunye nokufumaneka kwazo. Uninzi lweendlela zokuvelisa iiplastiki ezibolayo zixhomekeke kwizixhobo zolimo ezifana nombona, umoba, kunye ne-cassava. Amaxabiso azo ayaguquguquka ngenxa yokutshintsha kweemarike zeemveliso, imozulu engaqinisekanga, utshintsho lwesivuno sezityalo, kunye notshintsho kwimigaqo-nkqubo yezolimo kunye ne-biofuel. Ezi zinto zidibene nokuphazamisa uzinzo lwezoqoqosho lwenkqubo yokwenziwa kweplastiki ebolayo, zichaphazela inyathelo ngalinye ukusuka ekuthengweni kwe-feedstock ukuya kwi-polymerization kunye nokubumba.
Ukhuphiswano lwempahla yokutya ngokutya, ukutya kwezilwanyana, kunye nokusetyenziswa kwamandla kwenza kube nzima ngakumbi ukufikelela kwizinto eziluhlaza. Olu khuphiswano lunokubangela iingxoxo zokhuseleko lokutya kwaye lukhulise ukungazinzi kwamaxabiso, okwenza kube nzima kubavelisi ukuqinisekisa ukunikezelwa rhoqo nokufikelelekayo. Kwimimandla apho izityalo ezithile zinqongophele khona, le mingeni iyandiswa, nto leyo ethintela ukwandiswa kweenkqubo zokwenza iplastiki ezinobuhlobo nokusingqongileyo kwihlabathi liphela.
Ukusebenza kakuhle kokuguqula izinto kuvelisa omnye umqobo. Ukuguqula i-biomass ibe yi-monomers, kwaye ekugqibeleni, ii-biopolymers zifuna i-feedstock esemgangathweni ophezulu, engenangcolisi. Naluphi na utshintsho lunokunciphisa isivuno kwaye lunyuse iindleko zokucubungula. Kwanamanyathelo aphambili okuvelisa iplastiki ebolayo—njengokuvutshelwa, ukwenziwa kwe-polymerization, kunye nokubumba—ahlala edinga amandla amaninzi kwaye enovelwano kumgangatho wokufaka. I-feedstocks yesizukulwana sesibini efana nenkunkuma yezolimo ijongene nemiqobo yobuchwephesha kubandakanya unyango olunzima lwangaphambi kokuba lusetyenziswe kunye namazinga aphantsi okuguqula ngokubanzi.
Imingeni ye-logistics yongeza ubunzima obuthile. Ukuqokelelwa kwe-feedstock, ukugcinwa kwayo, kunye nokuthuthwa kwayo kuxhomekeke kwiziseko ezibanzi, ngakumbi ekuphatheni i-biomass engeyiyo yokutya. Ixesha lokuvuna linokubangela ukunyuka okukhawulezileyo kwiindleko zezinto okanye ukuphazamiseka kokunikezelwa kwayo. Ukuphatha, ukomisa, kunye nokulungisa i-biomass ngaphambi kokuba ilungiswe kufuna utyalo-mali kwiziseko ezizimeleyo, nto leyo ekhokelela kwiinkqubo ezingekho semgangathweni nezibiza kakhulu ezicela umngeni ekuhambeni okuqhubekayo okufunekayo kwimveliso enkulu ye-polymer esekwe kwi-bio.
Ukuhlangabezana neemfuno ezahlukeneyo zabathengi kunye nezicelo ezithile kudala uxinzelelo olongezelelweyo. Ii-aplikeshini zifuna iiparameter ezahlukeneyo zenkqubo yokuvelisa i-polymer ebolayo, ezinje ngamandla okutsalwa, izinga lokubola, kunye nokuziphatha kokubumba. Ukwanelisa ezi ngaphandle kokunciphisa ukubola okanye ukusebenza kakuhle kweendleko kunzima. Abathengi abakwiiphakheji banokubeka phambili ukubola okukhawulezileyo, ngelixa ezinye, njengakwii-aplikeshini zeemoto, zifuna ukuqina. Iindlela ezintsha zokubumba iplastiki ebolayo kunye notshintsho lwenkqubo kufuneka zilungiswe kakuhle kule migangatho yokusebenza eyahlukeneyo, zihlala zifuna iinkqubo ezintsonkothileyo, eziguquguqukayo kunye nokujonga ipropathi ngexesha langempela.
Ukulinganisela ukusebenza kwemveliso, ukubola kwezinto eziphilayo, kunye nokukhula kwazo kusengumngeni oqhubekayo. Umzekelo, ukonyusa ukuqina kwekristale kunokunyusa amandla emveliso, kodwa kunokunciphisa amazinga okubola kwezinto eziphilayo. Ukutshintsha iimeko zokucubungula—ezifana nexesha le-polymerization yeplastiki okanye i-injection molding—kufuneka kulawulwe kakuhle ukuze kulondolozwe ukusebenza kwe-eco kunye nokuveliswa kobuninzi. Izisombululo zokulinganisa ezikwi-inline, njengeemitha zoxinano lwe-propylene zeLonnmeter, zibonelela ngokubekwa esweni koxinano lwe-propylene ngexesha langempela kwaye zivumele ulawulo oluchanekileyo kwinqanaba loxinano lwe-propylene polymerization slurry lwenkqubo yeplastiki ebolayo, ixhasa umgangatho wemveliso ohambelanayo kunye nokusebenza okunokukhula.
Ulindelo olusemthethweni kunye nonxibelelwano olucacileyo luye lwakhula kakhulu kwinkqubo yokuveliswa kweplastiki ebolayo. Imithetho ingabeka imigangatho engqongqo yokubolayo, amaxesha okubolayo, kunye nokuzinza kwempahla yokutya. Kubalulekile ukwahlula phakathi kweplastiki ebolayo, ebolayo, kunye neplastiki ebolayo, njengoko ukulebhelisha okungafanelekanga okanye amabango emveliso angacacanga kunokubangela izohlwayo zomthetho kunye nokuphelisa ukuthembana kwabathengi. Abavelisi kufuneka batyale imali ekulebheliseni okucacileyo kunye namaxwebhu apheleleyo emveliso, bebonisa ukuthobela kunye neziqinisekiso ezihambelanayo ezinobuhlobo nokusingqongileyo.
Le mingeni ihlukeneyo—ixabiso elibanzi, ukubonelela, ukusebenza kakuhle kokuguqulwa, uthutho, ukulungelelaniswa kwesicelo, ukusebenza kwemveliso, kunye nokuthotyelwa kwemithetho—igxininisa ubunzima bokwandisa inkqubo yokwenza iplastiki ebolayo. Inyathelo ngalinye, ukusuka ekukhetheni nasekulinganisweni kwexesha langempela kwezinto zokutya ezifana ne-liquid propylene ukuya kuyilo lwenkqubo yonke yokwenza iplastiki ebolayo, ixhomekeke kwelinye kwaye ifuna ukwenziwa ngcono okuqhubekayo kunye nokucaca kuyo yonke ikhonkco lexabiso.
Ulawulo lweNkunkuma, Ubomi bokuphela, kunye neMigalelo yokusingqongileyo
Ukuqhekeka kweeplastiki ezinokubola kuxhomekeke kudibaniso lwezinto ezingqongileyo kunye neempawu zezinto. Ubushushu budlala indima ephambili; uninzi lweeplastiki ezinokubola, ezifana ne-polylactic acid (PLA), zibola ngokufanelekileyo kuphela kumaqondo obushushu okwenziwa komgquba kwimizi-mveliso, ngesiqhelo ngaphezulu kwama-55°C. Kula maqondo obushushu aphezulu, iipolymers ziyathamba, zenza kube lula ukufikelela kwiintsholongwane kwaye zonyusa i-enzyme hydrolysis. Ngokwahlukileyo koko, kumaqondo obushushu aphantsi okanye aphantsi—njengalawo akwiindawo zokulahla inkunkuma okanye kwizixhobo zokugquma zasekhaya—amazinga okubola ehla kakhulu, kwaye izinto ezifana nePLA zinokuhlala iminyaka.
Umswakama ubaluleke ngokulinganayo. Iinkqubo ze-composting zigcina umswakama ongama-40–60%, uluhlu oluxhasa i-metabolism yeentsholongwane kunye nokuqhekeka kwe-hydrolytic kwee-polymer chains. Amanzi asebenza njengendawo yokuthutha ii-enzyme kunye ne-reactant ekuwohlokeni kwe-polymer, ngakumbi kwii-esters, ezifumaneka kwiiplastiki ezibhalwe njenge-compostable. Umswakama onganeleyo uthintela yonke imisebenzi yeentsholongwane, ngelixa ukugqithisa kuguqula i-aerobic composting ibe ziimeko ze-anaerobic, okuthintela ukuqhekeka okusebenzayo kunye nokwandisa umngcipheko wokuveliswa kwe-methane.
Umsebenzi we-microbial uxhasa ukuguqulwa kwe-polymers zeplastiki zibe ziimveliso ezingezizo ezinobungozi. Ii-compost zemizi-mveliso zikhuthaza uluntu olwahlukeneyo lweebhaktheriya kunye nefungi, ezilungiselelwe ngokulawula umoya kunye nobushushu. Ezi microbes zikhupha uluhlu lwee-enzymes—ii-lipases, ii-esterases, kunye nee-depolymerase—eziqhekeza izakhiwo ze-polymeric zibe ziimolekyuli ezincinci ezifana ne-lactic acid okanye i-adipic acid, ezithi emva koko ziguqulwe zibe yi-biomass, amanzi, kunye ne-CO₂. Ukwakheka kwe-microbial consortia kuyatshintsha kwinkqubo yokwenza umgquba: iintlobo ze-thermophilic zilawula kubushushu obuphezulu kodwa zinika indawo yezinto eziphilayo eziphila ubomi obuphantsi njengoko iinqwaba zipholile. Ulwakhiwo lwe-molecular yeplastiki ethile kunye ne-crystallinity nazo zidlala indima ephambili; umzekelo, imixube esekelwe kwisitatshi iyafumaneka ngokukhawuleza kune-PLA ekristale kakhulu.
Iiplastiki ezibolayo zinegalelo ekulahlekeni kwenkunkuma ngokubonelela ngezinye iindlela ezenzelwe ukubola okulawulwayo endaweni yokuqokelelwa. Kwiimeko zokulahla inkunkuma, inzuzo yazo ilinganiselwe ngaphandle kokuba iimeko zokulahla inkunkuma zilungiselelwe ukubola kwenkunkuma—ezingaqhelekanga ngenxa yokunqongophala komoya kunye nokusebenza okufudumalayo. Nangona kunjalo, xa zithunyelwa kwizixhobo zokudibanisa inkunkuma zoshishino, iiplastiki eziqinisekisiweyo ezibolayo zinokuguqulwa zibe ngumgquba ozinzileyo, zisuse izinto eziphilayo ezithunyelwa kwezinye iindawo zokulahla inkunkuma okanye zitshiswe. Iindawo zaselwandle, eziphawulwa ngamaqondo obushushu aphantsi kunye nokwahluka okuncinci kweentsholongwane, zinciphisa kakhulu amazinga okubola, ngoko ke iiplastiki ezibolayo akufuneki zibonwe njengesisombululo sokulahlwa kwenkunkuma elwandle kodwa endaweni yoko zibonwe njengesisombululo sokulahla inkunkuma emva komthengi ukuba kukho iindlela ezifanelekileyo zokulahla inkunkuma.
Ulawulo lwenkunkuma yanamhlanje luyanda ukwamkela iiplastiki ezinokubola. Iinkqubo ze-compost zoshishino zenzelwe ukudala indawo efunekayo yokufudumala nokufuma ukuze konakaliswe ngempumelelo. Ezi nkqubo zilandela imigaqo yamazwe ngamazwe yokungenisa umoya, ukufuma, kunye nokulawula ubushushu, zilandelela izinto eziguquguqukayo ngeendlela ezifana nokubeka esweni imeko yeenqwaba ze-compost ngexesha langempela. Iimitha zoxinano lwe-Lonnmeter, umzekelo, zidlala indima ebalulekileyo kulawulo lwenkqubo ngokuqinisekisa ukuhambelana kokutya kunye nokwenza ngcono ukuhamba kwezinto: uxinano oluzinzileyo lubalulekile ukuvavanya ukuxubana kunye nokufuma ngokufanelekileyo, izinto ezichaphazela ngokuthe ngqo amazinga okuqhekeka kwi-compost.
Ukuhlanganiswa kwe-compost kufuna ukuba iiplastiki ezinokubola zichongwe kwaye zihlelwe ngokuchanekileyo. Uninzi lweendawo zifuna isiqinisekiso sokuba ziyabola ngokwemigangatho emiselweyo. Xa ezi mfuno zifezekisiwe, kwaye kugcinwe imigaqo yokusebenza, abagqumi banokucubungula iiplastiki ezinokubola ngokufanelekileyo, babuyisele ikhabhoni kunye nezondlo emhlabeni baze ngaloo ndlela bavale i-organic loop kwinkqubo yokwenziwa kweplastiki enobuhlobo nokusingqongileyo.
Ukuhamba kweeplastiki ezinokubola ngezi nkqubo, kuxhaswa yidatha yenkqubo echanekileyo efana nomlinganiselo woxinano wexesha langempela weLonnmeter, kwenza ukuba kubekho ukubola okuthembekileyo kunye nokugcinwa kwendalo. Nangona kunjalo, igalelo elipheleleyo kwindalo esingqongileyo alixhomekekanga kuphela kuyilo lwemveliso kunye nenkqubo yokwenziwa kweplastiki ezinokubola kodwa nakwindlela abathengi abaziphethe ngayo kunye nokusebenza kakuhle kweziseko zolawulo lwenkunkuma zasekuhlaleni. Ngaphandle kokuqokelelwa, ukuchongwa, kunye nokwenza umgquba ngempumelelo, umjikelo ocetywayo—inkqubo yokwenza iplastiki ezinokubola ukuze kuphuculwe umhlaba—unokuphazamiseka, unciphise iingenelo zendalo esingqongileyo.
Ukuze sibone impembelelo yeeparamitha eziphambili ze-compost kwisantya sokubola, itshathi elandelayo ishwankathela amaxesha aqikelelweyo okubola kweepolymers eziqhelekileyo ezinokubola phantsi kweemeko ezahlukeneyo:
| Uhlobo lwePolymer | Umgquba woShishino (55–70°C) | Umgquba Wasekhaya (15–30°C) | Indawo yokulahla inkunkuma/Emanzini (5–30°C) |
| I-PLA | Iinyanga ezi-3–6 | >Iminyaka emi-2 | Ingenasiphelo |
| Iingxube zeStarch | Iinyanga ezi-1–3 | Iinyanga ezi-6–12 | Icothiswe kakhulu |
| I-PBAT (iiBlends) | Iinyanga ezi-2–4 | >1 unyaka | Iminyaka ukuya kumashumi eminyaka |
Le tshati igxininisa imfuneko yokulawulwa kakuhle kweendawo zokugquma kunye nokuxhasa ukubekwa esweni kwenkqubo ukuze kubekho igalelo elifanelekileyo kwindalo esingqongileyo kuyo yonke inkqubo yokuveliswa kweplastiki ebolayo.
Izisombululo: Amaqhinga okuvelisa rhoqo, okusemgangathweni ophezulu
Ukwenziwa kweplastiki ebolayo esebenzayo, ehambelanayo, nehambelanayo kuxhomekeke kwiiNkqubo eziMiselweyo zokuSebenza (ii-SOP) kunye nokuhlolwa kwenkqubo okuqhubekayo. Abaphathi bezityalo kunye neenjineli kufuneka bamisele ii-SOP ezijongana ngqo nendlela yokwenza iplastiki ebolayo, zigxininisa ulawulo oluqinileyo kunye namaxwebhu kwinqanaba ngalinye. Oku kubandakanya ukuthathwa kwezinto eziluhlaza—ukugxininisa uvakalelo olulodwa lokufuma kunye nokuguquguquka kwezakha-mzimba ezisekelwe kwi-bio. Ukuqinisekisa ukulandeleka kwe-lot-to-lot kuvumela amaziko ukuba achonge ngokukhawuleza umthombo wokuphambuka kwaye athathe amanyathelo okulungisa.
Ukulawula iimpendulo ze-polymerization kubaluleke kakhulu kwinkqubo yokwenziwa kweplastiki ebolayo. Kwi-polylactic acid (PLA), oku kuthetha ukulawula ngokuqinileyo iimeko ze-ring-opening polymerization—ukukhethwa kwe-catalyst, ubushushu, i-pH, kunye nexesha—ukunciphisa ukwakheka kwemveliso kunye nokulahleka kobunzima be-molecular. Ngee-polymers ezithathwe kwi-fermentation ezifana ne-polyhydroxyalkanoates (PHA), ukuphelisa ungcoliseko ngokusebenzisa iinkqubo eziqinileyo zokucoca kwindawo kunye nokubulala iintsholongwane okuqinisekisiweyo kubalulekile ekuthinteleni ukulahleka kwesivuno kunye nokungaphumeleli komgangatho. Imisebenzi kufuneka yandise imigangatho ebhaliweyo ngokusebenzisa amanqanaba okubumba i-compounding, extrusion, kunye ne-biodegradable injection yeplastiki. Iiparamitha zenkqubo—ezifana neeprofayili zobushushu, isantya sezikrufu, amaxesha okuhlala, kunye nokomisa ngaphambi kokucubungula (ngokuqhelekileyo iiyure ezi-2-6 kwi-50-80°C)—kufuneka zigcinwe ngokuchanekileyo ukuthintela ukonakala kwe-biopolymer.
Ukubeka iliso ngokuqhubekayo ekusebenzeni sisiseko seenkqubo zanamhlanje zokwenziwa kweplastiki ezinobuhlobo nokusingqongileyo. Ukusebenzisa iimitha zoxinano ezikwi-inline-ezifana nezo zibonelelwa yiLonnmeter-kunye nee-viscometers ezikwi-intanethi kwenza ukuba izixhobo zikwazi ukujonga uxinano lwepropylene, uxinano lweslurry, kunye ne-viscosity ngexesha langempela. Impendulo enjalo ekhawulezileyo ivumela ukulungiswa ngokuthe ngqo kwenkqubo, ukuqinisekisa ukuba impendulo ye-polymerization ihlala ngaphakathi kweenkcukacha ezichanekileyo. Ukubeka iliso kuxinano lwepropylene ngexesha langempela kubaluleke kakhulu kwisigaba soxinano lweslurry lwepropylene polymerization, ukuthintela iibhetshi ezingachazwanga kunye nokunciphisa ukuphinda kusetyenziswe kunye nokuchithwa kwezinto. Ngokugcina ulawulo oluqinileyo ngezixhobo ezifana ne-Lonnmeter propylene density meter, abaqhubi banokuqinisekisa ukuba uxinano lwepropylene olumanzi luhlala luzinzile kuyo yonke imisebenzi yokwandisa kunye nomthamo opheleleyo. Oku akugcini nje ngokunyusa ukuphinda kusetyenziswe inkqubo kodwa kugcina ukuthotyelwa kwemigangatho yemveliso kunye neemfuno zomthetho.
Idatha evela ekubekweni esweni kwi-intanethi idla ngokubonwa njengeetshathi zolawulo lwenkqubo. Ezi zinokubonisa utshintsho lomzuzu ngomzuzu kwiimpawu eziphambili, ezifana nokuxinana kunye noxinano, zibonelela ngesilumkiso esikhawulezileyo sokuphambuka kwendlela (jonga uMfanekiso 1). Izenzo zokulungisa ngokukhawuleza zinciphisa umngcipheko wokuvelisa izinto ngaphandle kweenkcukacha ezijoliswe kuzo kwaye ziphucule isivuno siphela seenkqubo zemveliso yeplastiki ebolayo.
Ukwandisa imveliso ngelixa kulawula iindleko kuzisa imingeni engapheliyo kwinkqubo yokwenza iplastiki ebolayo. Izibonelelo kufuneka zisebenzise izikhokelo zokulawula iindleko ezenziwe ngobuchule: ukulinganiswa rhoqo kunye neeshedyuli zokugcinwa kwazo zonke izixhobo zokubeka esweni, ukufumana izinto ezininzi ngokuthembeka okubhaliweyo komthengisi, kunye nokuhlolwa kwenkqubo yokuxuba izongezo (kuba izongezo ezithile zinokuthintela ukuqhekeka kwepolymer). Uqeqesho olupheleleyo lwabaqhubi kunye nesatifikethi samaxesha onke kuzo zonke iinkqubo ezibalulekileyo zixhasa ngokuthe ngqo ukuphinda kuvele kuzo zonke iishifti kunye nokusebenza kwemveliso. Ukusebenzisa izixhobo zesalathiso ezisemgangathweni kunye nothelekiso phakathi kweelebhu-ezifana novavanyo loomatshini okanye imilinganiselo yokubola-yongeza umaleko ongezelelweyo wokuzithemba ukuba inkqubo yesiza esinye yokwenza iplastiki ebolayo iyafana neyenye.
Izityalo eziphambili kakhulu zibhekisa kwiindlela ezilungileyo zamazwe ngamazwe—ii-SOP ezihlolweyo zenyathelo ngalinye, amaxwebhu aqinileyo ochungechunge lokugcina, iindlela zoLawulo lweNkqubo yeStatistical, kunye nophononongo olucwangcisiweyo oludibanisa iziphumo zesayensi zamva nje. Le ndlela ivumela iinkqubo zemveliso yepolymer ebolayo esemgangathweni ophezulu, ephinda ivele, kwaye ithobelana nayo nayiphi na indlela. Ukulungiswa koxinano olukhawulezileyo kuyo yonke inkqubo yokwenziwa kweplastiki kusetyenziswa iimitha ezingaphakathi kuqinisekisa ukusebenza kakuhle kweendleko kunye nokufana okuphezulu kwemveliso.
Imibuzo Ebuzwa Rhoqo (Ii-FAQ)
Iyintoni inkqubo yokwenza i-polymerization yeplastiki kwimveliso yeplastiki ebolayo?
Inkqubo ye-polymerization yeplastiki ibandakanya ii-chemical reactions ezidibanisa iiyunithi ezincinci ze-monomer—ezifana ne-lactic acid okanye i-propylene—kwii-long-chain polymer molecules. Kwiiplastiki ezinokubola njenge-polylactic acid (PLA), i-ring-opening polymerization ye-lactide ngumgangatho weshishini, isebenzisa ii-catalysts ezifana ne-tin(II) octoate. Le nkqubo iphumela kwii-polymers ezinobunzima obuphezulu beemolekyuli ezineempawu zomzimba ezijoliswe kuzo. Ulwakhiwo lwe-polymer kunye nobude be-chain, zombini ezimiselwa ngexesha le-polymerization, zichaphazela ngokuthe ngqo amandla oomatshini kunye nesantya sokubola kwe-bio. Kwiinkqubo ezisekwe kwi-propylene, i-Ziegler-Natta catalysis iguqula ii-propylene monomers zibe zii-polypropylene chains. Xa bevelisa ii-variants ezinokubola, abaphandi banoku-copolymerize i-propylene ngee-comonomers ezinokubola okanye batshintshe umqolo we-polymer ngamaqela anobola ukuze kuphuculwe amazinga okubola kwendalo.
Uyenza njani iplastiki ebolayo?
Iplastiki ebolayo yenziwa ngokufumana izinto eziluhlaza ezivuselelekayo ezifana nomoba okanye umbona, zivundiswe zibe zii-monomers ezifana ne-lactic acid, kwaye ziphinde zibe yi-polymers ezifana ne-PLA. Ii-polymers eziphumayo zidityaniswe nezongezo ezisebenzayo ukuphucula ukuqhubekeka nokusebenza. Ezi ngxubevange zicutshungulwa ngeendlela zokubumba ezifana nokubumba ngenaliti okanye ukukhupha imveliso ukuze kwenziwe iimveliso zokugqibela. Iiparamitha zenkqubo zilawulwa ngokuqinileyo kulo lonke inqanaba ukuqinisekisa ukuthembeka kwezinto kunye nokubola kokusetyenziswa kwazo. Umzekelo kukupakisha ukutya okusekwe kwi-PLA, okuqala kwisitatshi sezityalo kuze kuphele njengee-wrappers ezinomgquba eziqinisekisiweyo phantsi kwemigangatho efana ne-EN 13432.
Ziziphi izinto ezibalulekileyo ekufuneka ziqwalaselwe xa kusenziwa i-plastic injection molding ebolayo?
Ukubumba ngempumelelo kweplastiki ezinokubola kuxhomekeke kulawulo oluchanekileyo lobushushu, njengoko ukufudumala kakhulu kukhokelela ekuwohlokeni kwangethuba kunye nokuncipha kwamandla emveliso. Ulawulo olufanelekileyo lokufuma lubalulekile kuba iipolymers ezinokubola zihlala zimanzisa phantsi kweemeko ezimanzi, nto leyo echaphazela ubunzima beemolekyuli kunye neempawu zomzimba. Amaxesha omjikelo afanelekileyo ayafuneka ukuqinisekisa ukuzaliswa ngokupheleleyo ngelixa kuthintelwa ukuvezwa kobushushu ixesha elide. Uyilo lokubola lunokwahluka kwiiplastiki eziqhelekileyo ngenxa yokuhamba okungaqhelekanga kunye neempawu zokupholisa zeeresini ezinokubola. Umzekelo, amaxesha okuhlala amafutshane kunye namazinga aphantsi okucheba anokugcina umgangatho wepolymer kwaye anciphise inkunkuma.
Ukubeka iliso kuxinano lwepropylene kwi-intanethi kunceda njani kwinkqubo yokuvelisa iplastiki ebolayo?
Iinkqubo zokulinganisa ngexesha langempela, ezifana neemitha zoxinano lwepropylene ezikwi-inline ezivela eLonnmeter, zibonelela ngempendulo ekhawulezileyo malunga noxinano lwepropylene ngaphakathi kwe-reactor ye-polymerization. Oku kuqinisekisa ukuba inkqubo ye-polymerization ihlala ngaphakathi kweeparamitha ezijoliswe kuzo, okuvumela abaqhubi ukuba balungise iimeko ngokukhawuleza. Uxinano lwepropylene oluzinzileyo luxhasa ukukhula kwetyathanga le-polymer okuzinzileyo kunye noyilo oluchanekileyo lweemolekyuli, ukunciphisa ukuguquguquka kwezinto kunye nokuphucula isivuno semveliso iyonke. Oku kubalulekile xa kusenziwa iintlobo ze-polypropylene ezinokubola, apho ulawulo lwenkqubo luchaphazela ngokuthe ngqo zombini iipropati zoomatshini kunye nokubola okujoliswe kuko.
Kutheni uxinano lwe-slurry lubalulekile kwinkqubo ye-propylene polymerization?
Uxinano lwe-propylene slurry—umxube we-suspended catalyst, i-monomer, kunye nokwenza i-polymer—luchaphazela ukudluliselwa kobushushu, amazinga okusabela, kunye nokusebenza kakuhle kwe-catalyst. Ukugcina uxinano olufanelekileyo lwe-slurry kuthintela iindawo ezishushu, kunciphisa umngcipheko wokungcoliswa kwe-reactor, kwaye kuvumela ukukhula kwe-polymer efanayo. Ukuguquguquka koxinano lwe-slurry kunokungenisa iziphene zezinto kunye nokuguquguquka ekusebenzeni koomatshini be-resin yokugqibela kunye neprofayili yokubola. Ulawulo oluqinileyo kuxinano lwe-slurry ke ngoko lubalulekile kuzinzo lwenkqubo kunye nomgangatho wemveliso ohambelanayo kwimveliso yeplastiki ebolayo.
Zeziphi izixhobo ezisetyenziselwa ukulinganisa uxinano lwe-propylene yolwelo ngexesha langempela?
Iimitha zoxinano oluphakathi, ezifana nezo zenziwe yiLonnmeter, zisetyenziselwa ukujonga uxinano lwe-propylene yolwelo ngqo kwimigca yemveliso. Ezi mitha zisebenza phantsi kweemeko zenkqubo enzima, zilinganisa uxinano rhoqo kwaye zithumela idatha yolawulo lwesityalo ngokukhawuleza. Ukufundwa ngokuchanekileyo, ngexesha langempela kwenza iqela lemveliso likwazi ukubona ukuphambuka ngokukhawuleza, lixhasa uhlengahlengiso olusebenzayo kwiimeko ze-reactor. Oku kuphumela kulawulo oluphuculweyo lwe-polymerization, ukuhambelana okungcono kwebhetshi, kunye nokusombulula iingxaki ngokufanelekileyo-kubalulekile kwiiprojekthi zovavanyo kunye neenkqubo zemveliso yeplastiki ebolayo kwinqanaba lorhwebo.
Ixesha leposi: Disemba-18-2025
