II. Iyini inkomishi yephepha ye-ayisikhilimu engaboli
I-Biodegradableizinkomishi zephepha lika-ayisikhilimubabe nokuwohloka. Kwehlisa umthwalo endaweni ezungezile. Inganciphisa ukungcola kwensiza ngokusebenzisa ukubola kwe-microbial kanye nokugaywa kabusha. Le nkomishi yephepha iyinketho eqhubekayo futhi enobungani bemvelo. Ihlinzeka ngesixazululo esimeme kakhudlwana embonini yezokupheka.
A. Incazelo kanye nezici
Izinkomishi zephepha lika-ayisikhilimu ezibolile ziyiziqukathi zephepha ezenziwe ngezinto ezibolayo. Ibhekana nenqubo yokuwohloka kwemvelo endaweni efanele. Uma kuqhathaniswa nezinkomishi zepulasitiki zendabuko, izinkomishi zephepha ezibolayo zinezici ezilandelayo:
1. Ukuvikelwa kwemvelo. I-PLA iyawohlokaizinkomishi zika-ayisikhilimuzenziwe ngesitashi sezitshalo. Ngakho, ingabola endaweni yemvelo. Lokhu kunganciphisa ukungcoliswa kwemvelo. Kunomthelela omuhle ekuvikeleni indawo ezungezile yoMhlaba.
2. Okuvuselelekayo. I-PLA yenziwe ngezinsiza ezivuselelekayo, ezifana nesitashi sezitshalo. Uma kuqhathaniswa namapulasitiki e-petrochemical, inqubo yokukhiqiza ye-PLA inokusetshenziswa okuphansi kwamandla kanye nokukhishwa kwegesi ebamba ukushisa. Inokusimama okungcono.
3. Ukungafihli. Izinkomishi zephepha ze-PLA zinokucaca okuhle. Lokhu kungabonisa ngokucacile umbala nokubukeka kwe-ayisikhilimu. Ingathuthukisa injabulo yabathengi ebonakalayo. Ngaphandle kwalokho, izinkomishi zephepha zingenziwa ngezifiso futhi zenziwe ngezifiso. Lokhu kunikeza abathengisi amathuba engeziwe okuthengisa.
4. Ukumelana nokushisa. Izinkomishi zephepha ze-PLA zisebenza kahle. Iyakwazi ukumelana nokudla ezingeni lokushisa elithile. Le nkomishi yephepha ifaneleka kakhulu ukubamba ukudla okubandayo nokushisayo okufana no-ayisikhilimu.
5. Ingasindi futhi iqinile. Izinkomishi zephepha ze-PLA azisindi futhi kulula ukuzithwala nokuzisebenzisa. Phakathi naleso sikhathi, izinkomishi zephepha ze-PLA zakhiwa ngenqubo ekhethekile yokwenza inkomishi yephepha. Lokhu kwenza isakhiwo saso siqine kakhudlwana futhi singajwayele ukuguga nokuphuka.
6. Isitifiketi samazwe ngamazwe. Izinkomishi zephepha ze-PLA zithobela izindinganiso zamazwe ngamazwe zesitifiketi semvelo. Isibonelo, izinga le-European EN13432 biodegradation standard kanye ne-American ASTM D6400 biodegradation standard. Inesiqiniseko sekhwalithi ephezulu.
B. Inqubo ye-Biodegradation yezinkomishi zephepha ezibolile
Lapho izinkomishi zika-ayisikhilimu eziwohlokayo ze-PLA zilahlwa, okulandelayo amaphuzu anemininingwane yenqubo yawo yokuwohloka:
Izici ezibalulekile ezenza ukuthi izinkomishi zephepha le-PLA zibole endaweni yemvelo umswakama kanye nezinga lokushisa. Emazingeni okushisa aphakathi nendawo, inkomishi yephepha izoqala inqubo yokubola.
Uhlobo lokuqala luyi-hydrolysis. Iinkomishi yephephaiqala inqubo ye-hydrolysis ngaphansi kwethonya lomswakama. Umswakama kanye nama-microorganisms angena kuma-micropores kanye nemifantu enkomishini yephepha futhi ahlanganyele nama-molecule e-PLA, okuholela ekuphenduleni kokubola.
Uhlobo lwesibili yi-enzymatic hydrolysis. Ama-Enzymes ama-biochemical catalysts angasheshisa ukusabela kokubola. Ama-Enzyme akhona endaweni ezungezile angakwazi ukugqugquzela i-hydrolysis yezinkomishi zephepha ze-PLA. Iphula ama-PLA polymers abe ama-molecule amancane. Lawa ma-molecule amancane azoncibilika kancane kancane endaweni ezungezile futhi aqhubeke nokubola.
Uhlobo lwesithathu ukubola kwe-microbial. Izinkomishi zephepha ze-PLA ziyabola ngenxa yokuthi kunezinambuzane eziningi ezingabola i-PLA. Lawa ma-microorganisms azosebenzisa i-PLA njengamandla futhi awehlise abe yi-carbon dioxide, amanzi, kanye ne-biomass ngokusebenzisa izinqubo zokubola nokubola.
Izinga lokuwohloka kwezinkomishi zephepha le-PLA lincike ezintweni eziningi. Okufana nomswakama, izinga lokushisa, izimo zenhlabathi, nobukhulu nokushuba kwezinkomishi zephepha.
Ngokuvamile, izinkomishi zephepha le-PLA zidinga isikhathi eside ukuze zilulaze ngokugcwele. Inqubo yokucekelwa phansi kwezinkomishi zephepha ze-PLA ivamise ukwenzeka ezindaweni ezikhiqiza umquba wezimboni noma ezindaweni ezifanele zemvelo. Phakathi kwazo, izimo ezivumela umswakama, izinga lokushisa, nokusebenza kwamagciwane. Ezindaweni zokulahla imfucuza yasendlini noma ezindaweni ezingafanele, izinga lokuwohloka kwalo lingase lihambe kancane. Ngakho-ke, lapho uphatha izinkomishi zephepha le-PLA, kufanele kuqinisekiswe ukuthi zibekwe ohlelweni olufanele lokwelapha imfucuza. Lokhu kunganikeza izimo ezivumayo zokucekelwa phansi.