Ka Hana Polymerization
Pendahuluan
He mau hui kemika nā polymers i haku ʻia me nā molekala nui, kaulahao lōʻihi i hana ʻia me nā ʻāpana hana hou i kapa ʻia he monomers. ʻO ka polymerization ke kaʻina hana kemika e hui pū ai kēia mau monomers e hana i nā polymers. He mea koʻikoʻi kēia kaʻina hana i ka ʻoihana kemika a kōkua i ka hoʻokumu ʻana o nā ʻano mea waiwai like ʻole, me nā plastics, rubber, a me nā fibers synthetic.
ʻO ka pahuhopu o kēia ʻatikala e wehewehe i nā ʻano hana, nā ʻano, a me nā noi o nā hopena polymerization. Hiki ke hana ʻia nā kaʻina hana polymerization ma o nā ʻano hana like ʻole, me ʻelua mau māhele nui: ka polymerization hoʻohui a me ka polymerization condensation.
Nā ʻano o ka Polymerization
Hoʻohui Polymerization
ʻO ka polymerization hoʻohui kahi hana e hana ai nā monomers me nā pilina pālua a ʻekolu paha e hana i kahi polymer me ka ʻole o ka hana ʻana i nā huahana ʻaoʻao. ʻO nā polymers i hana ʻia e kēia ʻano polymerization ua kapa ʻia he polymers hoʻohui.
ʻanuʻu:
1. Hoʻomaka: Hoʻomaka ka hopena ke hana kahi mea hoʻomaka i nā radical manuahi, ions, a i ʻole nā mea hoʻouluulu e hiki ke uhaki i nā pilina pālua i nā monomers.
2. Hoʻolaha: Hoʻopili nā radical manuahi a i ʻole nā ions i hoʻokumu ʻia me nā monomers, e hana ana i nā wēlau hana hou e hiki ke hana me nā monomers ʻē aʻe.
3. Hoʻopau: Hoʻōki ka hopena ke hui ʻelua mau radical manuahi a hana i kahi pilina covalent, a i ʻole ke hoʻōki kekahi ʻano hana ʻē aʻe i ka hoʻolaha ʻana.
laʻana:
– Poly(ethylene): Hana ka Ethylene monomer (C2H4) ma o ke kaulahao o nā radical manuahi e hana i ka poly(ethylene).
– Poly(vinyl chloride) (PVC): Hoʻohui ʻia nā monomers vinyl chloride (C2H3Cl) ma o ka hoʻomaka ʻana, ka hoʻolaha ʻana, a me ka hoʻopau ʻana.
Ka Polymerization Condensation
ʻO ka polymerization condensation e pili ana i nā monomers nona ka liʻiliʻi ʻelua mau hui hana reactive a hana i kahi polymer me ka hopena o kahi huahana, e like me ka wai a i ʻole ka methanol.
ʻanuʻu:
1. Hoʻomaka: ʻO nā Monomers nona nā hui hana reactive e hana pū kekahi me kekahi.
2. Hoʻokumu ʻia: Hoʻokumu ʻia ʻana o nā pilina ma waena o nā monomers, me ka hoʻokuʻu ʻia ʻana o nā molekala māmā, e like me H2O a i ʻole HCl.
3. Ka ulu ʻana o ke kaulahao: Ke hoʻomau nei kēia kaʻina hana a pau nā monomers a i ʻole ʻaʻole kūpono hou nā kūlana hopena.
laʻana:
– Nylon-6,6: Hana ʻia mai ka hopena ma waena o ka hexamethylenediamine a me ka waikawa adipic, kahi e hoʻopuka ai i ka wai ma ke ʻano he huahana ʻaoʻao.
– Polyester: I hana ʻia mai ka hopena ma waena o ka waikawa terephthalic a me ka ethylene glycol, me ka wai ma ke ʻano he huahana ʻaoʻao.
ʻAno hana polymerization
ʻO ka Polymerization Radical Free
ʻO ka polymerization radical manuahi kekahi o nā ʻano hana polymerization hoʻohui maʻamau. Hoʻomaka kēia kaʻina hana me ka hoʻokumu ʻia ʻana o nā radical manuahi reactive kiʻekiʻe, maʻamau ma o ka thermal a i ʻole photoinitiation.
1. Hoʻomaka: Ua wāwahi ʻia nā molekole hoʻomaka e like me ka benzoyl peroxide a i ʻole azobisisobutyronitrile (AIBN) e hana i nā radical manuahi.
\[ \text{(Note, AIBN) → 2 \cdot (Radical, )} \]
2. Hoʻolaha: Hana nā radical manuahi me nā monomers e hana i nā radical monomer i hoʻonui ʻia:
\[ \text{(Radical + Monomer) → (R-Polymer )} \]
3. Hoʻopau: Hoʻohui ʻia nā radical manuahi ʻelua e hana i kahi molekala non-radical a hoʻōki i ka hopena kaulahao:
\[ \text{(R + R ) → Hua Hoʻohua ʻAʻole Radical} \]
Ka Polymerization Ionic
Pili kēia polymerization i ka hoʻokumu ʻia ʻana o nā ions (cations a i ʻole anions) ma ke ʻano he reactive species. Hiki ke hoʻokaʻawale ʻia ka polymerization Ionic i ʻelua ʻano nui, ʻo ia hoʻi:
– Cationic Polymerization: Hoʻokomo i kahi ʻano cationic ma ke ʻano he mea hoʻomaka. Hoʻohana pinepine ʻia me nā monomers nona nā hui hāʻawi uila e like me isobutylene.
– Anionic Polymerization: Hoʻokomo i nā ions i hoʻopiʻi maikaʻi ʻole ʻia (anions) ma ke ʻano he mau mea hoʻomaka. Hoʻohana ʻia ma nā monomers nona nā hui ʻae electron e like me styrene.
Hoʻohuihui Polymerization
Hoʻopili ʻia kēia ʻano polymerization e nā mea hoʻouluulu paʻakikī metala hoʻololi, ʻo kahi laʻana ʻo ka polymerization Ziegler-Natta i hoʻohana ʻia e hana i ka polyethylene stereo-regular a me ka polypropylene.
1. Nā mea hoʻouluulu: Hoʻohana ʻia nā metala hoʻololi e like me ka titanium chloride me nā hui organometallic e like me ka alumini triethyl (AlEt3).
2. Hana: Hoʻohui nā Monomers ma ke kūlana hana o ka hui metala.
Nā noi polymerization
ʻOihana Palakiko
ʻO nā palakiko nā huahana polymer i ʻike nui ʻia a hoʻohana nui ʻia. Hana ʻia lākou ma o nā kaʻina hana polymerization hoʻohui a me ka condensation. ʻO nā hiʻohiʻona o nā huahana polymerization palakiko maʻamau e komo pū ana me ka polyethylene, polypropylene, PVC, a me PET (polyethylene terephthalate). Hoʻohana ʻia nā palakiko i ka hana ʻana i nā ʻōpala, nā mea pāʻani, nā paipu, a me nā ʻano huahana mea kūʻai like ʻole.
Mea Fiber
ʻO nā olonā synthetic e like me ka nylon a me ka polyester ka hopena o ka polymerization condensation. Hoʻohana ʻia lākou i ka hana ʻana i nā textiles, nā lole, a me nā mea hale e like me nā kāpeti a me ke kaula. Koho pinepine ʻia nā olonā no ko lākou ikaika, ke kūpaʻa i ka abrasion, a me ka elasticity.
ʻO ka laholio hana
ʻO nā laholio synthetic, e like me ka polibutadiene a me ka styrene-butadiene (SBR), he mau huahana ia o ka polymerization hoʻohui o nā monomers i loaʻa ka diene. Hoʻohana ʻia kēia mau laholio i ka hana ʻana i nā kaila kaʻa, nā sila, a me nā noi ʻoihana like ʻole ma muli o ko lākou kūpaʻa i ka abrasion a me ka deformation.
Nā Resins Epoxy a me nā Polymers Thermosetting
ʻO nā resins Epoxy ka hopena o ka polymerization condensation e hana ʻia ma ka mahana o ka lumi a i ʻole me ka hoʻomehana ʻana. Hoʻohana ʻia lākou i nā mea hoʻopili, nā pena, a me nā mea i hui pū ʻia e pono ai ke kū'ē i ka wela a me nā kemika. ʻAʻole hiki ke hoʻoheheʻe hou ʻia kēia mau polymers thermosetting ma hope o ka hoʻōla ʻana, ʻaʻole e like me nā polymers thermoplastic.
ʻO ka lāʻau lapaʻau
ʻO nā polymers i hoʻohana ʻia i nā noi biomedical e komo pū me ka polylactide (PLA) a me ka poly(tetrahydrofurane) (PTHF), i hoʻohana ʻia e hana i nā mea implant bioresorbable. Ua hoʻolālā ʻia kēia mau polymers e biodegrade i loko o ke kino, e hōʻemi ana i ka pono no ka wehe ʻana i ka lua o ke ʻoki kino.
Nā Mea Hana Uila
ʻO nā polymers electroactive he mau polymers e hoʻololi i ke ʻano ma lalo o ka mana o kahi kahua uila, i hoʻohana pinepine ʻia i nā actuators a me nā sensors. ʻO nā laʻana e komo pū me ka poly(3,4-ethylenedioxythiophene) (PEDOT), kahi i hoʻohana ʻia i nā mea uila e like me nā touchscreens.
Ka hopena
ʻO nā hopena polymerization he mau kaʻina hana kemika koʻikoʻi i ka ʻoihana kemika hou, e hoʻomākaukau ana i ke ala no nā ʻano huahana a me nā noi e hoʻololi i ko mākou ola o kēlā me kēia lā. Ma ka hoʻomaopopo ʻana i nā ʻano hana a me nā ʻano o ka polymerization, a me kā lākou noi, hiki iā mākou ke hoʻomohala i nā mea hou me nā waiwai i hoʻonui ʻia no nā pono e hiki mai ana. Hoʻokani kēlā me kēia i nā kuleana kūikawā o ka polymerization hoʻohui a me ka polymerization condensation i ka hoʻokumu ʻana o kēia mau mea, a ke hoʻomau nei ka ʻepekema i ka holomua e ʻike i nā ala hou e hoʻomaikaʻi ai i kēia mau kaʻina hana a loaʻa nā noi hou no nā polymers.
