Nrog rau txoj kev loj hlob ntawm kev lag luam thiab kev txhim kho ntawm tib neeg txoj kev ua neej nyob, qhov kev thov rau cov khoom siv yas yog nce zuj zus nyob rau ib hnub, thiab "dawb paug" coj los ntawm cov yas yog qhov hnyav dua.Yog li ntawd, kev tshawb fawb thiab kev tsim cov yas tshiab degradable los ua ib txoj hauv kev tseem ceeb los kho cov teeb meem ib puag ncig.Polymer plastics tuaj yeem degrade nyob rau hauv ntau yam mob, thiab thermal degradation tshwm sim nyob rau hauv qhov kev txiav txim ntawm tshav kub.Mechanical degradation tshwm sim nyob rau hauv qhov kev txiav txim ntawm txhua yam quab yuam, oxidative degradation nyob rau hauv qhov kev txiav txim ntawm oxygen, thiab biochemical degradation nyob rau hauv qhov kev txiav txim ntawm cov tshuaj.Cov yas degradable yog hais txog cov yas uas yooj yim degraded nyob rau hauv ib puag ncig ntuj los ntawm kev ntxiv ib co ntawm cov additives (xws li starch, modified starch los yog lwm yam cellulose, photosensitizers, biodegraders, thiab lwm yam) nyob rau hauv cov txheej txheem ntau lawm.
Raws li lawv cov txheej txheem degradation, biodegradable plastics tuaj yeem muab faib ua photodegradable plastics, biodegradable plastics, photobiodegradable plastics thiab chemically degradable plastics.
Thaum cov saw hlau molecular ntawm photodegradable plastics raug rhuav tshem los ntawm cov txheej txheem photochemical, cov yas poob nws lub cev lub zog thiab embrittlements, ces dhau los ntawm xwm.
Kev xeb ntawm ciam teb dhau los ua hmoov, uas nkag mus rau hauv av thiab rov nkag mus rau hauv lub voj voog lom neeg raws li kev ua ntawm cov kab mob.
Biodegradable plastics tuaj yeem muab faib ua biodegradable plastics thiab biodegradable plastics raws li lawv cov txheej txheem degradation thiab hom kev puas tsuaj.Tam sim no, hmoov txhuv nplej siab thiab polyester plastics yog feem ntau kawm thiab siv.
Starch yas yog qhov tshwj xeeb tshaj yog txaus nyiam vim nws cov cuab yeej ua haujlwm yooj yim thiab tus nqi qis.Synthetic macromolecule biodegradable plastics xa mus rau biodegradable plastics synthesized los ntawm cov txheej txheem tshuaj.Nws tuaj yeem ua ke los ntawm kev kawm cov qauv zoo ib yam li cov khoom siv ntuj tsim los ntawm cov khoom siv polymer biodegradable los yog cov yas nrog cov pab pawg ua haujlwm tsis zoo.
Biodestructive degradable plastics, tseem hu ua cov yas tawg, yog cov txheej txheem sib xyaw ntawm biodegradable polymers thiab cov yas dav dav, xws li cov hmoov txhuv nplej siab thiab polyolefin.Lawv tau ua ke ua ke nyob rau hauv ib daim ntawv, thiab qhov degradation nyob rau hauv ib puag ncig ntuj tsis tiav, thiab tej zaum yuav ua rau muaj kuab paug thib ob.Hauv biodegradable polymers, qhov sib ntxiv ntawm photosensitizers tuaj yeem ua rau cov polymers ob qho tib si photodegradable thiab biodegradable.
Photobiodegradable polymer cov ntaub ntawv nyob rau hauv tej yam kev mob yuav ua rau tus degradation tus nqi tswj tau zoo, xws li hmoov txhuv nplej siab ntxiv photodegradable polymer cov ntaub ntawv PE tom qab degradation, ua PE ntxeem tau, tshwj xeeb deg cheeb tsam zoo heev, nrog oxygen, lub teeb, dej sib cuag zoo heev, PE degradation tus nqi nce loj heev.
Piv nrog rau photodegradable plastics, biodegradable plastics tau dhau los ua lub ntsiab lus kub hauv kev tsim cov yas biodegradable.Vim tias biodegradable plastics tsis hnyav dhau ntawm ib puag ncig, thiab nws yooj yim dua kom degrade me me molecules nyob rau hauv txoj cai.Nws muaj qhov zoo ntawm cov khoom me me, kev ua haujlwm yooj yim, siab zog thiab tus nqi qis.Biodegradable plastics muaj ntau yam kev siv.Nyob rau hauv lub tebchaws United States mas siv nyob rau hauv zus tau tej cov decomposing khib nyiab hnab, khw hnab;Nyob rau hauv Western Europe, biodegradable plastics yog siv nyob rau hauv cov tshuaj zawv plaub hau fwj, cov hnab khib nyiab thiab ib lub hnab ntim khoom siv.Biodegradable plastics yog siv rau hauv cov hauv qab no:
(1) Cov khoom ntim
(2) Agricultural mulch
(3) Cov khoom siv niaj hnub
(4) Cov ntaub ntawv kho mob pov tseg
(5) Artificial pob txha, tawv nqaij, phais pob txha ntsia hlau, phais suture
(6) Textile fibers
(7) Tswj cov xuab zeb daj thiab kev npaj hauv nroog.
Thaum biodegradable plastics siv rau hauv bioengineering thiab kho mob degradable polymer cov ntaub ntawv, lawv cov yam ntxwv ntawm biodegradation tsis tuaj yeem muab piv nrog cov hauv paus photodegradable plastics.Cov tshuaj uas tsis muaj molecular degraded tuaj yeem ncaj qha nkag mus rau hauv cov metabolism hauv cov kab mob, thiab muaj ntau yam kev cia siab rau hauv cov ntaub so ntswg kab lis kev cai, tswj cov tshuaj tso tawm, thiab cov khoom siv cog qoob loo.
Lub sij hawm xa tuaj: Nov-17-2022