Biodegradable hnab yas cov ntaub ntawv tuaj yeem muab faib ua peb pawg raws li lawv txoj kev degradation:
Ib qho yog cov khoom siv biodegradable tag nrho thiab lwm qhov yog cov khoom puas biodegradable.
Ua tiav cov ntaub ntawv biodegradablexa mus rau cov khoom uas tuaj yeem ua tiav biodegraded los ntawm cov kab mob, fungi, algae thiab lwm yam kab mob nyob rau hauv ib puag ncig ib puag ncig tom qab siv thiab pov tseg, thiab thaum kawg tsim cov pa roj carbon dioxide thiab dej tsis tsim cov pa phem, uas tsis muaj kev phom sij rau ib puag ncig thiab cuam tshuam rau ib puag ncig. Tib neeg ua lub neej noj qab nyob zoo thiab ua lub luag haujlwm tseem ceeb hauv kev tiv thaiv ib puag ncig.
Nws yog tsuas yog ua los ntawm hmoov txhuv nplej siab, cellulose thiab lwm yam ntuj macromolecules los yog ua liaj ua teb thiab sideline khoom los ntawm microbial fermentation los yog synthesis ntawm biodegradable polymers, xws li aliphatic polyester polymers PLA PHA, PBAT, PBS starch, thiab lwm yam. Nws muaj biocompatibility zoo sib deev thiab bioabsorbable, ib puag ncig. phooj ywg. Qhov no yog ib txoj hauv kev zoo los tswj cov "dawb paug" tshwm sim los ntawm cov khoom siv yas. Nws decomposition feem ntau yog vim lub cev degradation ntawm cov khoom vim yog kev loj hlob sai ntawm cov kab mob.
Cov ntaub ntawv biodegradable yog dav siv nyob rau hauv ntau yam lag luam thiab tuaj yeem hloov pauv cov yas zoo tib yam. Cov ntaub ntawv tiv thaiv ib puag ncig, cov ntaub ntawv ntim khoom thiab cov ntaub ntawv kho mob tau siv dav.
Cov hnab ntim khoom noj, hnab ntim khoom thiab cov hnab khib nyiab ua los ntawm cov khoom siv biodegradable yog nrov vim lawv biodegradability. Biodegradable ntim cov ntaub ntawv feem ntau yog tsim los ntawm kev ntxiv biodegradable polymers rau cov yeeb yaj kiab sib xyaw lossis ncaj qha sib xyaw nrog cov khoom sib xyaw. Cov khoom ntim khoom noj thiab cov thawv ntim khoom feem ntau xav tau cov ntaub ntawv uas ua kom cov zaub mov tsis lwj, tsis muaj oxygen, thiab tsis muaj tshuaj lom. Ntawm lawv, feem ntau cov neeg sawv cev yog polyhydroxy butyrate (PHB), polyhydroxy valerate (PHV) thiab lawv cov copolymers. Nws cov khoom siv lub cev zoo ib yam li polyethylene thiab polypropylene, thiab nws cov khoom siv hluav taws xob zoo yog qhov zoo. Tom qab siv, lawv tuaj yeem raug biodegraded lossis incinerated. Lawv cov pa oxygen tsuas yog sib npaug rau cov pa nkag mus rau hauv qhov chaw los ntawm photosynthesis, thiab CO2 tsim tom qab kho yog tag nrho cov nyiaj CO2 absorbed los ntawm photosynthesis. Yog li, nws muaj peev xwm muab PHB thiab PHV kev kho mob rau hauv lub voj voog lom neeg.
Kev puas tsuaj biodegradable cov ntaub ntawvtseem hu ua incompletely degradable cov ntaub ntawv thiab semi-degradable cov ntaub ntawv. Lawv feem ntau yog ua los ntawm polyethylene thiab polystyrene tov nrog additives, los yog starch thiab cellulose tov nrog zoo tib yam yas. Qhov tsis zoo yog tias lub zog txhua yam tsis txaus los hloov cov khoom qub qub, nws tsis tuaj yeem degraded kiag li, thiab nws yog ib qho yooj yim ua rau cov pa phem thib ob. Nws decomposition feem ntau yog vim kev puas tsuaj thiab tsis muaj zog ntawm cov saw hlau polymer los ntawm cov khoom siv ntxiv, uas txo qhov hnyav molecular ntawm cov polymer mus rau qhov uas nws tuaj yeem zom tau los ntawm cov kab mob.