Lipotso tsa Mehlala le Puisano ea Mefuta ea Li-polymer
Polima ke molek'hule e kholo e entsoeng ka li-unit tse nyane tsa limolek'hule tse bitsoang li-monomers. Li-polymer li sebelisoa lits'ebetsong tse fapaneng, ho tloha polasetiking le rabara ho ea ho likhoele tsa maiketsetso le thepa ea kaho. Ho utloisisa li-polymer ho bohlokoa k'hemistri, saenseng ea thepa le liindastering tse fapaneng. Sengoloa sena se tla tšohla mehlala e 'maloa ea mathata mabapi le mefuta ea li-polymer le ho fana ka litharollo tse tebileng mathateng ana.
Lipotso tsa Mehlala le Puisano
Potso ea 1:
Bolela mefuta e meraro ea li-polymer ho latela mohloli oa tsona oa pele 'me u fane ka mohlala oa e 'ngoe le e 'ngoe.
Puisano:
1. Li-polymer tsa tlhaho:
Li-polymer tsa tlhaho ke li-polymer tse hlahang ka tlhaho tikolohong. Mehlala ea li-polymer tsa tlhaho e kenyelletsa:
– Cellulose: E fumaneha maboteng a sele ea limela.
– Rabara ea Tlhaho: E fumanoa lero la sefate sa Hevea brasiliensis.
– Protheine: E kang collagen e fumanehang letlalong le liseleng tse hokahaneng tsa liphoofolo.
2. Li-polymer tsa maiketsetso:
Li-polymer tsa maiketsetso ke li-polymer tse hlahisoang ke batho ka mekhoa ea lik'hemik'hale tsa maiketsetso. Mehlala ea li-polymer tsa maiketsetso e kenyelletsa:
– Polyethylene (PE): E sebelisoa ho etsa mekotla ea polasetiki.
– Polypropylene (PP): E sebediswa indastering ya dikoloi le diphuthelong tsa dijo.
– Polyvinyl Chloride (PVC): E sebediswa tlhahisong ya diphaephe le dithapo.
3. Li-polymer tse sa tsoakoang ka mokhoa o itseng:
Li-polymer tse entsoeng ka mokhoa o sa tsoakoang ke liphetoho tsa li-polymer tsa tlhaho ho ntlafatsa thepa ea tsona. Mehlala ea li-polymer tse entsoeng ka mokhoa o sa tsoakoang e kenyelletsa:
– Cellulose Acetate: E entsoe ka cellulose e fetotsoeng ho sebelisoa acetic acid, e sebelisoang filiming ea lifoto.
– Nitrocellulose: E fumanoa ka nitration ea cellulose, e sebelisoang tlhahisong ea liqhomane le lipente.
Potso ea 2:
Hlalosa phapang pakeng tsa li-polymer tsa thermoplastic le thermoset, 'me u fane ka mehlala e 'meli ea e 'ngoe le e 'ngoe.
Puisano:
1. Li-polymer tsa Thermoplastic (Thermoplastics):
Polima ena e nolofala ha e futhumatsoa mme e thatafala ha e phodisitsoe, mme e ka feta ts'ebetsong ena kgafetsa. Sena se etsa hore ho be bonolo ho e sebedisa hape. Mohlala:
– Polyethylene (PE): E sebelisoa ho etsa mekotla ea polasetiki le libotlolo.
– Polystyrene (PS): E sebediswa ho etseng thepa ya ho kwahela mocheso le ho paka dijo.
2. Li-polymer tsa Thermosetting (Li-thermosets):
Li-polymer tsena, hang ha li entsoe ka ho futhumatsa le ho pholisa, li ke ke tsa qhibilihisoa hape. Li na le sebopeho se matla 'me li ke ke tsa sebelisoa hape ka tsela e tšoanang le ea thermoplastics. Mohlala:
– Bakelite: E fumaneha ka har'a liswichi tsa motlakase le lihako tsa lisebelisoa tsa ho pheha.
– Epoxy: E sebediswa ho dikhomaretsi, dikobo, le dikompo tse tshwarellang nako e telele.
Potso ea 3:
Hlalosa mokhoa oa ho eketsa polymerization 'me u fane ka mehlala ea li-polymer tse hlahisoang ka mokhoa ona.
Puisano:
Ho eketsa polymerization ke mokhoa oa ho theha li-polymer ka karabelo ea ketane moo li-monomer tse nang le litlamo tse habeli (hangata litlamo tse habeli tsa carbon-carbon) li kopanang ntle le ho hlahisa lihlahisoa tse ling.
Mekhahlelo e kenyeletsang polymerization:
1. Qalo: Ho thehoa ha li-radical tse lokolohileng kapa li-ion tse qalang karabelo.
2. Ho ata: Li-radical tse lokolohileng kapa li-ion li arabela le li-monomers, li etsa liketane tse telele tsa polymer.
3. Ho Fela: Karabelo e fela ha di-free radical tse pedi di kopana.
Mehlala ea li-polymer tse eketsang:
– Polyethylene (PE): E hlahisitsoe ho tsoa ho ethylene monomer (C2H4).
– Polypropylene (PP): E hlahisitsoe ho tsoa ho propylene monomer (C3H6).
Potso ea 4:
Ho boleloa'ng ka condensation polymerization 'me u fane ka mehlala e' meli ea li-polymer tse hlahisoang ka mokhoa ona.
Puisano:
Ho kopanya polymerization ke mokhoa oa ho kopanya polymerization oo li-monomer li kopanang ka ho tlosa limolek'hule tse nyane tse kang metsi kapa methanol.
Mehlala ea polymerization ea condensation ke:
1. Sebopeho sa Nylon:
Nylon 6,6 e thehoa ka karabelo pakeng tsa hexamethylenediamine le adipic acid, e hlahisang metsi e le sehlahisoa se setseng.
\[ \mongolo{H}_2\mongolo{N}-(\mongolo{CH}_2)_6\sengolo{NH}_2 + \mongolo{HOOC}-(\mongolo{CH}_2)_4\sengolwa{COOH} \rightarrow(-\text{NH}-(\text{CH}_2)_6\text{NH-CO}-(\)-CO_4{CH}_mangolo \mongolo{H}_2\mongolo{O} \]
2. Sebopeho sa Polyester:
Li-polyester tse kang polyethylene terephthalate (PET) li thehoa ka karabelo pakeng tsa terephthalic acid le ethylene glycol, e hlahisang metsi e le sehlahisoa se setseng.
\[ \mongolo{HOOC-}\mongolo{C}_6\mongolo{H}_4\mongolo{COOH} + \mongolo{HO-CH}_2\mongolo{CH}_2\mongolo{OH} \mowa (-\text{O-CH}_2\text{CH}_2-\text{OCO-}\text{C}_6\text{H}_4){H}_4 \mongolo{H}_2\mongolo{O} \]
Potso ea 5:
Thepa ea 'mele ea li-polymer e ka fetoloa joang ka ho sebelisa li-plasticizer? Fana ka mohlala.
Puisano:
Li-plasticizer ke lintho tse eketsoang ho li-polymer ho eketsa ho tenyetseha, ho fokotsa ho robeha ha bonolo, le ho theola mocheso oa phetoho ea khalase (Tg). Li-plasticizer li sebetsa ka ho fokotsa matla a litlamo tsa limolek'hule ka har'a polymer, ho lumella liketane tsa polymer ho tsamaea ka bolokolohi le ho eketsa ho plasticity ea thepa.
Mehlala ea ho sebelisa li-plasticizer:
– PVC le di-plasticizer: Ha ho etswa dithapo tsa motlakase, PVC e kopanngwa le di-plasticizer tse kang di-phthalates ho etsa hore e tenyetsehe le ho tshwarella haholoanyane.
– Cellulose acetate le plasticizers: E sebelisoa tlhahisong ea lifilimi le li-lacquer ho etsa hore lihlahisoa li se ke tsa thekesela haholo.
Qetello
Li-polymer ke thepa e feto-fetohang haholo e bapalang karolo ea bohlokoa bophelong ba letsatsi le letsatsi le theknoloji ea sejoale-joale. Ka ho utloisisa mefuta ea li-polymer le lits'ebetso tsa polymerization, re ka nts'etsapele thepa e ncha e nang le thepa e lakatsehang le ho ntlafatsa ts'ebeliso ea eona masimong a fapaneng. Thuto ea li-polymer e qala ka ho sebetsana le litaba tsena le ho fumana kutloisiso e tebileng ea melao-motheo ea motheo ea saense ea li-polymer. Sengoloa sena se ikemiselitse ho fana ka kutloisiso ea pele ea mefuta ea li-polymer le ho khothaletsa babali ho tsoela pele ho ithuta le ho batlisisa ka botebo ka li-polymer le ts'ebeliso ea tsona.
