Karabelo e qalisoang ke mahlaseli e ka aroloa ka mokhoa o ikhethileng e le mefuta e 'meli: (1) crosslinking le scissionand (2) grafting le pholiso.
Crosslinking ke sebopeho sa bond ea intermolecular ea liketane tsa polymer.Thedegree of crosslinking e lekana le lethal dose ea mahlaseli.Ha e hloke li-unsaturated kapa lihlopha tse ling tse sebetsang haholoanyane.Ntle le mekhelo e meng (joalo ka lipolymers tse nang le aromatics), ha e fapane haholo le sebopeho sa lik'hemik'hale.Ha e fapane haholo le mocheso.Le hoja mokhoa oa ho hokahanya mahlaseli a kotsi o 'nile oa ithutoa ho tloha ha o qala ho sibolloa, ho ntse ho se na tumellano e pharaletseng mabapi le sebopeho sa eona.Mochine oa crosslinking ka kakaretso o fapana le li-polymers tse amehang.Mokhoa o amoheloang ke lefats'e o kenyelletsa ho petsoha ha bond ea C-H ho ketane e le 'ngoe ea polima ho etsa athomo ea haedrojene, e lateloe ke ho ntšoa ha athomo ea bobeli ea haedrojene ho tsoa ketane ea boahelani ho hlahisa hydrogen ea molek'hule.Joale li-radicals tse peli tse haufi tsa polymeric li kopana ho etsa crosslink.Phello e akaretsang ea crosslinking ke hore boima ba molek'hule ea polymer bo eketseha butle-butle lethal dose ea mahlaseli, e lebisang ho liketane tse nang le makala ho fihlela, qetellong ho etsoa marang-rang a mararo a polymer ha ketane e 'ngoe le e' ngoe ea polymer e hokahanngoa. ho isa ketane enngwe.
Ka lehlakoreng le leng, scission ke mokhoa o fapaneng oa ho kopanya moo ho phunyeha ha C-C bondsoccurs.Crosslinking e eketsa boima ba limolek'hule tse tloaelehileng athe ts'ebetso ea ho qetela e fokotsa boima ba 'mele.Haeba matla a mahlaseli a phahame, ho robeha ketane ho etsahala ka ho phunyeha ha bond ea C-C.Leha ho le joalo, ka aeratedsolution medium, mokhoa oa machane oa scission o tsoela pele ka mokhoa o sa tobang.Li-radicals tsa mahala tsa thepolymeric li hlahisoa ke li-radicals tse se nang solvent, tse seng li ntse li thehoa ke mahlaseli.Ho senyeha ha oxidative ea li-polymers ho itšetlehile ka solventused tsamaisong.Haele hantle, ho senyeha ha polymer ho qothisana lehlokoa le oxidation ea solvent.
Grafting ke mokhoa oo li-monomers li hlahisoang ka thōko ho ketane ea polymer moo ascuring e leng polima e potlakileng ea motsoako oa oligomer monomer ho etsa seaparo, se kopantsoeng ke matla a 'mele ho substrate.Ka mokhoa o bonolo, mekhoa e joalo e kenyelletsa litsamaiso tse fapaneng, karolo e ka tlase ke filimi, likhoele kapa phofo, 'me monoma e le mokelikeli, mouoane kapa tharollo.Ho na le kamano e haufi lipakeng tsa ho hlomathisa le ho folisa le hoja ho na le liphapang tse itseng.Ha e le hantle, ha ho na moeli oa nako bakeng sa ts'ebetso ea grafting.E ka nka metsotso, lihora kapa matsatsi, athe ho phekola hangata ke ts'ebetso e potlakileng haholo e etsahalang ka nako ea motsotsoana.Ka ho hlomathiseletsoa, li-covalent C-C li tlamahanoa, athe ho folisa, tlamahano hangata e kenyelletsa weakervan der Waals kapa London dispersion forces.van der Waals bonding e sebetsa libakeng tse hole moo ho sa feteng letho kapa ho fapanyetsanoang teng 'me hangata e amahanngoa le matla a manyane.Leha ho le joalo, covalentbonding, e sebetsa libakeng tse nyane tsa nyutlelie 'me e amahanngoa le ho kopana ha elektrone, phapanyetsano, 'me ka lebaka leo matla a phahameng.Karolo e 'ngoe ea bohlokoa ea ho phekola ke monyetla oa hore ho hlomathiseletsoa ka nako e le 'ngoe le ho folisa ho ka lebisa ntlafatsong ea thepa e felileng, haholo-holo ho khomarela le ho fetoha habonolo.
Ho hlomathisa ho tsoela pele ka litsela tse tharo tse fapaneng: (a) pele ho mahlaseli;(b) peroxidation le (c) thekeniki ea mahlakore a mabeli.Mokhoa oa pele ho mahlaseli, mokokotlo oa pele oa polymer o khabisoa ka har'a vacuum kapa ka pel'a khase e sa sebetseng ho etsa li-radicals tsa mahala.The irradiated polymer substrate e ntan'o phekoloa ka monoma, e leng mokelikeli kapa mouoane kapa e le tharollo ka har'a motsoako o loketseng.Leha ho le joalo, ka mokhoa oa theperoxidation grafting, kutu polymer e tlas'a mahlaseli a mangata a matla ka pel'a moea kapa oksijene.Phello ke ho thehoa ha hydroperoxides kapa diperoxides ho itšetlehile ka mofuta oa mokokotlo oa polymeric le maemo a mahlaseli.Lihlahisoa tsa peroxy, tse tsitsitseng, li phekoloa ka monoma ka mocheso o phahameng, moo li-peroxide li kenang ho bola ha li-radicals, ebe li qala ho hlomathiseletsoa.Molemo oa mokhoa ona ke hore li-peroxyproducts tse bohareng li ka bolokoa nako e telele pele li etsa mohato oa ho hlomathisa.Ka lehlakoreng le leng, ka mokhoa oa themutual irradiation, polymer le monomers li khabisoa ka nako e le 'ngoe ho theha li-radicals tsa mahala, ka hona, ho eketsoa hoa etsahala.Kaha li-monomers ha li hlahisoe ke mahlaseli ka mokhoa oa pele ho mahlaseli, molemo o totobetseng oa mokhoa oo ke hore ha o na bothata ba ho thehoa ha homopolymer e hlahang ka mokhoa oa nako e le 'ngoe.Leha ho le joalo, phoso e entsoeng ka mokhoa oa pre-radiation ke scission ea polymer ea motheo ka lebaka la tataiso ea eona, e hlahisang haholo-holo ho thehoa ha li-block copolymers ho e-na le graftcopolymers.
Nako ea poso: May-03-2017