Txij li thaum lub advent ntawm yas, nws tau dav siv nyob rau hauv txhua yam ntawm tib neeg lub neej, nqa zoo heev yooj yim rau tib neeg tsim thiab lub neej. Txawm li cas los xij, thaum nws yooj yim, nws siv thiab pov tseg kuj ua rau muaj kev ua qias tuaj ib puag ncig, nrog rau cov pa phem dawb xws li dej ntws, thaj av, thiab dej hiav txwv.
Polyethylene (PE) yog cov yas siv dav siv thiab ua lwm txoj hauv kev rau cov khoom siv biodegradable.
PE muaj crystallinity zoo, dej vapor barrier zog thiab huab cua tsis kam, thiab cov khoom no tuaj yeem raug hu ua "PE yam ntxwv".
Nyob rau hauv tus txheej txheem ntawm kev nrhiav kom daws tau qhov "yas pa phem" los ntawm lub hauv paus, ntxiv rau kev nrhiav tshiab ib puag ncig tus phooj ywg lwm cov ntaub ntawv, ib txoj kev tseem ceeb heev yog nrhiav ib puag ncig nyob rau hauv cov ntaub ntawv uas twb muaj lawm uas yuav degraded los ntawm ib puag ncig thiab ua ib feem. ntawm lub voj voog ntau lawm Tus phooj ywg cov ntaub ntawv, uas tsis tsuas yog txuag tau ntau ntawm cov neeg ua haujlwm thiab cov nqi khoom siv, tab sis kuj daws qhov teeb meem loj ntawm ib puag ncig hauv ib lub sijhawm luv luv.
Cov khoom ntawm biodegradable cov ntaub ntawv ua tau raws li cov kev xav tau ntawm kev siv thaum lub sijhawm khaws cia, thiab tom qab siv, lawv tuaj yeem degraded rau hauv cov khoom uas tsis muaj teeb meem rau ib puag ncig hauv ntuj tsim.
Cov ntaub ntawv biodegradable sib txawv muaj cov yam ntxwv sib txawv thiab muaj lawv tus kheej qhov zoo thiab qhov tsis zoo. Ntawm lawv, PLA thiab PBAT muaj cov qib siab ntawm kev lag luam, thiab lawv lub peev xwm tsim khoom tau ua haujlwm tseem ceeb hauv kev ua lag luam. Raws li kev txhawb nqa ntawm kev txwv cov yas, cov khoom lag luam biodegradable yog kub heev, thiab cov tuam txhab yas loj tau nthuav dav lawv cov khoom. Tam sim no, lub ntiaj teb txhua xyoo muaj peev xwm ntawm PLA yog ntau tshaj 400,000 tons, thiab nws xav tias yuav muaj ntau tshaj 3 lab tons hauv peb lub xyoos tom ntej. Rau qee qhov, qhov no qhia tau hais tias PLA thiab PBAT cov ntaub ntawv yog cov khoom siv biodegradable nrog kev lees paub zoo hauv kev ua lag luam.
PBS hauv cov ntaub ntawv biodegradable kuj yog cov khoom siv nrog cov qib siab ntawm kev lees paub, kev siv ntau dua, thiab cov cuab yeej paub tab ntau dua.
Lub peev xwm tsim khoom uas twb muaj lawm thiab kev cia siab tias yuav nce ntxiv rau yav tom ntej ntawm cov khoom siv degradable xws li PHA, PPC, PGA, PCL, thiab lwm yam. Qhov laj thawj tseem ceeb yog tias cov ntaub ntawv biodegradable no tseem nyob rau theem pib, thev naus laus zis tsis paub qab hau thiab tus nqi siab dhau lawm, yog li qhov kev lees paub tsis siab, thiab tam sim no nws tsis tuaj yeem sib tw nrog PLA thiab PBAT.
Cov ntaub ntawv biodegradable sib txawv muaj cov yam ntxwv sib txawv thiab muaj lawv tus kheej qhov zoo thiab qhov tsis zoo. Txawm hais tias lawv tsis muaj "PE yam ntxwv", qhov tseeb, cov khoom siv biodegradable feem ntau yog aliphatic polyesters, xws li PLA thiab PBS, uas muaj esters. Bonded PE, ester daim ntawv cog lus hauv nws cov saw molecular muab nws biodegradability, thiab aliphatic saw muab nws "PE yam ntxwv".
Lub melting point thiab mechanical zog, kub tsis kam, degradation tus nqi, thiab tus nqi ntawm PBAT thiab PBS tuaj yeem them rau daim ntawv thov PE hauv kev lag luam khoom pov tseg.
Lub degree ntawm industrialization ntawm PLA thiab PBAT yog qhov siab, thiab nws tseem yog cov kev taw qhia ntawm kev loj hlob ntawm kuv lub teb chaws. PLA thiab PBAT muaj cov yam ntxwv sib txawv. PLA yog cov yas tawv, thiab PBAT yog cov yas mos. PLA nrog cov tshuab cua tshuab tsis zoo yog feem ntau sib xyaw nrog PBAT nrog zoo toughness, uas tuaj yeem txhim kho cov txheej txheem ntawm cov tshuab cua tshuab tsis ua rau nws cov khoom lom. degradability. Yog li ntawd, nws tsis yog qhov exaggeration hais tias PLA thiab PBAT tau dhau los ua cov khoom tseem ceeb ntawm cov khoom degradable.
Post lub sij hawm: Jan-14-2022