Kuvandudza uye kushandiswa kwemapurasitiki epolymer anodegradable, biodegradable plastics imhando yemhando itsva ine basa rekushatisa zvinhu zvepolymer, mukushandiswa kwekushandisa, zvine chekuita nemhando imwe chete yepurasitiki yakajairika ine hutano hunoenderana uye inoshanda yekushandisa, uye mushure mekushanda kwayo kwakazara, izvo zvinhu zvinogona kukurumidza kuderedzwa mumamiriro echisikigo mamiriro ezvinhu anova nyore kupihwa zvimedu zvemukati kana kupwanyiwa, uye nekufamba kwenguva kumwe kushatisa kunova pakupedzisira oxidation zvigadzirwa (CO2 nemvura), dzokera kune zvakasikwa.
Kuvandudza uye kushandiswa kwebiodegradablepolymer mapurasitiki, biodegradable mapurasitiki imhando yemhando nyowani ine basa rekushatisa zvinhu zvepolymer, mukushandiswa kwekushandisa, zvine chekuita nemhando imwechete yepurasitiki yakajairika ine hutano hunoenderana uye yakakodzera mashandiro ekushandisa, uye mushure mekushanda kwayo kwakazara, izvo zvinyorwa. inogona kukurumidza kuderedzwa mumamiriro echisikigo mamiriro ezvinhu anova nyore kupihwa zvimedu zvemukati kana kupwanywa, uye nekufamba kwenguva kumwe kushatisa kunopedzisira kwave zvigadzirwa zve oxidation (CO2 nemvura), kudzokera kune zvakasikwa.
Zvichienderana nekusvibiswa kwezvakatipoteredza kunokonzerwa nemarara epurasitiki, pamwe nekudiwa kwekuchengetedzwa kwezvakatipoteredza uye zvinodiwa nevanhu, zvinokasira kudzidza zvinoparara zvepolymer zvinhu.Mune imwe nguva uye pasi pemamwe mamiriro ezvakatipoteredza, chimiro chemakemikari emapurasitiki anoodegradable achachinja.Zvinoenderana nezvikonzero zvekuchinja kwechimiro chayo chemakemikari, mapurasitiki anogona kupatsanurwa muzvikamu zviviri: biodegradable mapurasitiki uye mapurasitiki anogona kugadzirwa.
1. Degradation mechanism yemapurasitiki anoparara
Kazhinji kutaura, purasitiki inoora inoreva rudzi rwepurasitiki inogona kuomeswa kuita mamorekuru madiki kuburikidza nekuita kwema microorganisms muvhu kana solar radiation.Inofanirwa kusangana nezvinodiwa zvekushandiswa kwezvigadzirwa uye zviri nyore kugadzirisa pahwaro hwehwaro. biodegradable properties.Hunhu hwekuita kwechiedza chezuva pane zvinhu zvepolymer ndiyo yakazara mhedzisiro yechiedza cheultraviolet muchiedza chezuva uye okisijeni mumhepo, saka inodaidzwa zvakare kunzi photooxidation degradation.Tora polyolefin semuenzaniso kutsanangura mashandiro ephotooxidation degradation.Muchidimbu, photooxidation inokonzera kuputika kweketani kana kuyambuka kwemapolymers, uye mamwe mapoka ane oxygen-anoshanda, akadai se carboxylic acids, peroxides, ketoni uye doro, anoumbwa mukuita uku.Catalyst zvisaririra mumapolymers uye kutangwa kweperoxide nemapoka ecarboxyl akaunzwa panguva yekugadziriswa ndiwo akanyanya kukonzeresa.
Pasi pekuita kwema microorganisms (kunyanya fungi, mabhakitiriya kana algae, nezvimwewo), mapolymers anogona kukukurwa kana kugadzirwa kuti akonzere shanduko muchimiro chavo chemakemikari uye kuderera kwehuremu hwemamorekuru.Iyo meshini yekuita inogona kunyanya kukamurwa kuita maviri mamiriro:
(1) biophysical action.Kureva, mushure mekukukurwa kwezvigadzirwa zvepurasitiki nema microorganisms, biological masero kukura, kusimudzira kuparara kwemapolymers, ionization kana proton, chiitiko ichi chemuviri papolymer chakakonzera kukuvadzwa kwemagetsi, huremu hwepamusoro hwepolymer kuita zvidimbu zve oligomer, kuti zadzisa chinangwa chekuora muviri.
(2) biochemical action - zvakananga chiito che enzymes.Mamiriro ezvinhu aya anokonzerwa nekukukurwa kwema enzymes anoburitswa nefungi kana mabhakitiriya, izvo zvinotungamira mukutsemuka kana oxidative disintegration yemapurasitiki, uye kukonzeresa kupatsanuka kana oxidative kuparara kwemapolymer asinganyunguke kuita zvimedu zvinonyungudika mumvura, zvichigadzira madiki madiki mamorekuru makomisheni (CH4, CO2 uye H2O) kusvika pakuora kwekupedzisira.
Pane kazhinji kaviri fungidziro nezve maitiro e biodegradation yezvinhu zvepolymer zvinotungamira kune biodegradation.Imwe yacho invasive kucheka kubva kumagumo echeni.Naizvozvo, zvimiro zvezvimiro zvemidziyo, senge kuumbwa, huru uye mativi cheni chimiro, saizi yemapoka ekupedzisira, uye kuvapo kana kusavapo kwenzvimbo steric kuramba, ndizvo zvinhu zvakakosha zvinokanganisa mashandiro avo.Pakati pavo, iyo huru cheni zvivakwa zvine simba rakakura.Kana iyo ketani huru yepolymer ine zvisungo zviri nyore hydrolyzed, zvichave nyore biodegraded.Chechipiri, kana musana wacho uchichinja-chinja, kuderera kwehuwandu huchave huchikurumidza, asi kana musana wakaoma uye wakarongeka, chiyero chekuora chinononoka.
Iyo biodegradability yezvinhu zvepolymer inoderedzwa nebazi uye kuyambuka.Semuenzaniso, kuiswa kwemapoka e-hydrophobic pamagumo epolylactic acid (PLA) molecular chain inogona kuderedza kuderera kwehuwandu padanho rekutanga rekuora.Izvi zvinodaro nekuti mukutanga kushatisa maitiro, kukukurwa kwePLA kunonyanya kuenderana nechimiro chekupedzisira kwema molecular cheni, uye kuwedzera kwemapoka ehydrophobic kunotungamirira kuderera kwekukura kwayo.Pamusoro pezvo, vamwe vaongorori vakadzidza chimiro chemakemikari emapolymer uye huremu hwemamorekuru hwezvinhu zvinotora basa rakakosha mukudzikisira kwavo.
2. Kuvandudzwa kwemapurasitiki anoparara
Iyo nzira yekuvandudza ye biodegradable mapurasitiki mune ramangwana anogona kuve anotevera:
(1) biodegradable mapurasitiki akagadzirwa nekudzidza iyo biodegradation mashandiro emapolymer anoshatisa, uye block copolymerization yemapurasitiki anoodegradable nemapolymers aripo akajairwa, microbial polymers uye mapolima echisikigo akadzidzwa uye akagadzirwa.
(2) kutsvaga tupukanana tunokwanisa kugadzira mapurasitiki epolymer, kuongorora mapolymer matsva, kuongorora magadzirirwo awo zvakadzama, kuvandudza kubereka kwavo kuburikidza nenzira dziripo uye nzira dzeinjiniya dzemajini, uye kudzidza nzira dzakasimba dzekurima tupukanana.
(3) teerera kudzora kwehuwandu hwekudzikisira, gadzira vanosimudzira kushatisa uye vanodzikamisa kuti vavandudze mashandiro ebiodegradation emapurasitiki anoparara, kuderedza mutengo wavo, uye kuwedzera kushandiswa kwemusika.
(4) tsvagurudza uye gadza tsananguro yakabatana yemapurasitiki anoshatisa, pfumisa nekuvandudza nzira yekuongorora ye biodegradation, uye nekuwedzera kunzwisisa maitiro ekudzikisira.
Nguva yekutumira: Aug-13-2019