ʻO Polytetrafluoroethylene (polytetrafluoroethylene) paha ka fluoropolymer i hoʻohana nui ʻia no ka mea he nui nā ʻano e lilo ai ia i mea kūpono no nā ʻano hana like ʻole. ʻOi aku ka maʻalahi ma mua o nā paipu like ʻē aʻe a hiki ke kūʻē i nā kemika ʻoihana āpau.
ʻO ka pae mahana ma kahi o -330°F a i 500°F, e hāʻawi ana i ka pae mahana ākea loa ma waena o nā fluoropolymers. Eia kekahi, he mau waiwai uila maikaʻi loa a me ka permeability magnetic haʻahaʻa. ʻO ka paipu Ptfe ka paipu hoʻokolohua i hoʻohana nui ʻia a me nā noi kahi e pono ai ke kūpaʻa kemika a me ka maʻemaʻe.PTFEhe haʻahaʻa loa kona coefficient o ka friction a ʻo ia kekahi o nā mea "paheʻe" i ʻike ʻia
Nā Hiʻohiʻona:
100% resin PTFE maʻemaʻe
Hoʻohālikelike ʻia me FEP, PFA, HP PFA, UHP PFA, ETFE, ECTFE, nā paipu fluoropolymer maʻalahi loa
He inert kemika, kū i ka aneane o nā kemika ʻoihana a me nā mea hoʻoheheʻe
Pae mahana ākea
Haʻahaʻa ke komo ʻana
ʻO ka hoʻopau ʻana o ka ʻili laumania ʻaʻole e pipili
Ka helu haʻahaʻa loa o ka friction
Hana uila maikaʻi loa
ʻAʻole hiki ke lapalapa
ʻAʻohe ʻawahia
Nā noi:
keʻena hoʻokolohua
Kaʻina hana kemika
Nā lako hana loiloi a me ke kaʻina hana
Ka nānā ʻana i ka hoʻokuʻu ʻana
Haʻahaʻa ka mahana
wela kiʻekiʻe
Uila
ʻozone
ʻO ke ʻano o nā molekala PTFE
Hana ʻia ka Polytetrafluoroethylene (PTFE) e ka polymerization o nā molekala tetrafluoroethylene he nui
ʻAʻole hōʻike kēia kiʻikuhi PTFE maʻalahi i ke ʻano ʻekolu-dimensional o ka molekala. I loko o ka poly(ethylene molekala maʻalahi), ua hoʻopili wale ʻia ke kuamoʻo kalapona o ka molekala e nā ʻātoma hydrogen, a he palupalu loa kēia kaulahao-ʻaʻole ia he molekala linear.
Eia nō naʻe, i loko o ka polytetrafluoroethylene, ua lawa ka nui o ka ʻātoma fluorine i loko o kahi hui CF2 e hoʻopilikia ai i ka ʻātoma fluorine ma ka hui e pili ana. Pono ʻoe e hoʻomanaʻo he 3 mau pālua o nā electrons lone e kū ana i waho i kēlā me kēia ʻātoma fluorine.
ʻO ka hopena o kēia, ʻo ia ke kāohi ʻana i ka wili ʻana o ka pilina hoʻokahi kalapona-kalapona. Hoʻonohonoho ʻia nā ʻātoma fluorine i kahi mamao loa mai nā ʻātoma fluorine e pili ana. Hoʻokomo ka wili ʻana i nā kuʻi ʻana o nā hoa pili ʻelua ma waena o nā ʻātoma fluorine ma nā ʻātoma kalapona e pili ana - kahi e hoʻolilo ai i ka wili ʻana i mea maikaʻi ʻole.
Hoʻopaʻa ka mana hoʻokuke i ka molekala i loko o ke ʻano koʻokoʻo, a ua hoʻonohonoho ʻia nā ʻātoma fluorine i loko o kahi ʻōwili mālie loa—ua hoʻonohonoho ʻia nā ʻātoma fluorine i loko o kahi ʻōwili a puni ke kuamoʻo kalapona. E ʻomi pū ʻia kēia mau ʻāpana kēpau e like me nā penikala lōʻihi a lahilahi i loko o kahi pahu.
He mana koʻikoʻi ko kēia hoʻonohonoho pili kokoke i nā mana intermolecular, e like me kāu e ʻike ai
Nā mana intermolecular a me ke kiko heheʻe o PTFE
Ua ʻōlelo ʻia ke kiko heheʻe o ka polytetrafluoroethylene he 327°C. He kiʻekiʻe loa kēia no kēia polymer, no laila pono e nui nā mana van der Waals ma waena o nā molekala
No ke aha i ʻōlelo ai ka poʻe he nāwaliwali nā mana van der Waals ma PTFE?
Hoʻokumu ʻia ka ikaika hoʻopuehu van der Waals e nā dipoles loli pōkole i hana ʻia i ka wā e neʻe ai nā electrons i loko o ka mole. No ka mea, he nui ka mole PTFE, e manaʻo ʻoe i kahi ikaika hoʻopuehu nui no ka mea he nui nā electrons e hiki ke neʻe.
ʻO ke kūlana maʻamau, ʻo ka nui o ka molekala, ʻo ka nui o ka mana hoʻopuehu
Eia nō naʻe, he pilikia ko PTFE. He electronegative loa ka Fluorine. Hoʻopaʻa paʻa ia i nā electrons i loko o ka pilina carbon-fluorine, a paʻa loa i hiki ʻole i nā electrons ke neʻe e like me kou manaʻo. Ke wehewehe nei mākou i ka pilina carbon-fluorine me ka loaʻa ʻole o ka polarization ikaika
Hoʻokomo pū nā mana Van der Waals i nā pilina dipole-dipole. Akā i loko o ka polytetrafluoroethylene (PTFE), ua hoʻopuni ʻia kēlā me kēia molekala e kahi papa o nā ʻātoma fluorine i hoʻopiʻi iki ʻia. I kēia hihia, ʻo ka pilina wale nō ma waena o nā molekala ka repulsion like!
No laila, ʻoi aku ka nāwaliwali o ka ikaika hoʻopuehu ma mua o kou manaʻo, a ʻo ka pilina dipole-dipole e hoʻoulu ai i ka repulsion. ʻAʻole he mea kupanaha ke ʻōlelo nei ka poʻe he nāwaliwali loa ka ikaika van der Waals ma PTFE. ʻAʻole ʻoe e loaʻa maoli i ka ikaika repulsive, no ka mea, ʻoi aku ka nui o ka mana o ka ikaika hoʻopuehu ma mua o ka pilina dipole-dipole, akā ʻo ka hopena net, ʻo ia ka nāwaliwali o ka ikaika van der Waals.
Akā, he kiʻekiʻe loa ka pae heheʻe o ka PTFE, no laila, pono e ikaika loa ka ikaika e hoʻopaʻa ai i nā molekala.
Pehea e hiki ai i ka PTFE ke loaʻa i kahi kiko heheʻe kiʻekiʻe?
He kristal loa ka PTFE, ma kēia ʻano he wahi nui, aia nā molekala i kahi hoʻonohonoho maʻamau. E hoʻomanaʻo, hiki ke manaʻo ʻia nā molekala PTFE he mau koʻokoʻo lōʻihi. E hui pū ʻia kēia mau pou.
ʻO ke ʻano kēia, ʻoiai ʻaʻole hiki i ka mole ptfe ke hana i nā dipoles manawa nui loa, hiki ke hoʻohana pono ʻia nā dipoles.
No laila, he nāwaliwali a ikaika paha nā ikaika van der Waals ma PTFE?
Manaʻo wau hiki iā ʻolua ke pololei! Inā hoʻonohonoho ʻia nā kaulahao polytetrafluoroethylene (PTFE) i ʻole e pili kokoke loa nā kaulahao, e nāwaliwali loa ka ikaika ma waena o lākou a e haʻahaʻa loa ke kiko heheʻe
Akā ma ke ao maoli, pili pono nā molekala. ʻAʻole paha e like ka ikaika o nā mana Van der Waals me ko lākou ikaika, akā ʻo ke ʻano o ka PTFE ʻo ia hoʻi ke manaʻo nei lākou i ka hopena nui loa, e hana ana i nā pilina intermolecular ikaika a me nā kiko heheʻe kiʻekiʻe.
He ʻokoʻa kēia me nā mana ʻē aʻe, e like me ka mana pilina dipole-dipole, ka mea i hoʻemi wale ʻia e 23 mau manawa, a i ʻole ʻelua manawa i hoʻemi ʻia ka mamao e 8 mau manawa.
No laila, ʻo ka hoʻopili paʻa ʻana o nā molekala ʻano koʻokoʻo ma PTFE e hoʻonui i ka pono o ka hoʻopuehu ʻana
Nā waiwai ʻaʻole e pipili
ʻO kēia ke kumu e pipili ʻole ai ka wai a me ka ʻaila i ka ʻili o ka PTFE, a no ke aha e hiki ai iā ʻoe ke palai i nā hua manu i loko o kahi pā i uhi ʻia me ka PTFE me ka ʻole e pipili i ka pā.
Pono ʻoe e noʻonoʻo i nā mana e hoʻopaʻa ai i nā molekala ʻē aʻe ma luna o ka ʻili oPTFE. Hiki ke komo pū me kekahi ʻano pilina kemika, ka ikaika van der Waals a i ʻole ka pilina hydrogen
Hoʻopaʻa kemika
He ikaika loa ka pilina kalapona-fluorine, a he mea hiki ʻole i nā molekala ʻē aʻe ke hiki i ke kaulahao kalapona e hana ai i kekahi hopena pani. He mea hiki ʻole ke hana ʻia kahi pilina kemika
nā pūʻali koa van der Waals
Ua ʻike mākou ʻaʻole ikaika loa ka ikaika van der Waals ma PTFE, a e hana wale ia i ka PTFE i kahi kiko heheʻe kiʻekiʻe, no ka mea, ua kokoke loa nā molekala a he pilina maikaʻi loa ko lākou.
Akā, he ʻokoʻa ia no nā molekala ʻē aʻe kokoke i ka ʻili o ka PTFE. ʻO nā molekala liʻiliʻi (e like me nā molekala wai a i ʻole nā molekala aila) e loaʻa wale kahi pilina liʻiliʻi me ka ʻili, a he liʻiliʻi wale nō ka nui o ka van der Waals e hoʻoulu ʻia.
ʻAʻole e like ke ʻano o kahi molekala nui (e like me ka protein), no laila ʻaʻole lawa ka pilina kūpono ma waena o ia a me ka ʻili e lanakila ai i ke ʻano polarization haʻahaʻa o ka PTFE.
ʻO kēlā me kēia ʻaoʻao, ʻo ka ikaika van der Waals ma waena o ka ʻili o ka PTFE a me nā mea e hoʻopuni ana he liʻiliʻi a ʻaʻole pono
Nā pilina hydrogen
Ua ʻōwili piha ʻia nā molekole PTFE ma luna o ka ʻili e nā ʻātoma fluorine. He electronegative loa kēia mau ʻātoma fluorine, no laila ke lawe nei lākou a pau i kahi kekelē o ka hoʻopiʻi maikaʻi ʻole. Loaʻa i kēlā me kēia fluorine he 3 mau pālua o nā electrons lone e puka ana.
ʻO kēia nā kūlana e pono ai no ka hoʻokumu ʻana o nā pilina hydrogen, e like me ka lone pair ma ka fluorine a me ka ʻātoma hydrogen i loko o ka wai. Akā ʻike maopopo ʻaʻole kēia e hana, inā ʻaʻole e loaʻa kahi huki ikaika ma waena o nā molekala PTFE a me nā molekala wai, a e pipili ka wai i ka PTFE.
Hōʻuluʻulu manaʻo
ʻAʻohe ala kūpono no nā molekala ʻē aʻe e hoʻopili pono ai i ka ʻili o PTFE, no laila he ʻili ʻaʻole e pipili.
ʻO ka haʻalulu haʻahaʻa
He haʻahaʻa loa ke koina o ka friction o ka PTFE. ʻO ia hoʻi, inā he ʻili i uhi ʻia me ka ptfe kou, e paheʻe maʻalahi nā mea ʻē aʻe ma luna.
Aia ma lalo iho kahi hōʻuluʻulu manaʻo pōkole o nā mea e hana nei. Loaʻa kēia mai kahi pepa 1992 i kapa ʻia ʻo "Friction and Wear of Polytetrafluoroethylene".
I ka hoʻomaka ʻana o ka paheʻe ʻana, haki ka ʻili PTFE a hoʻoili ʻia ke kaumaha i nā wahi a pau e paheʻe ana. ʻO ke ʻano kēia e ʻaʻahu ʻia ka ʻili PTFE.
I ka hoʻomau ʻana o ka paheʻe ʻana, ua wehe ʻia nā poloka i loko o nā ʻili lahilahi.
I ka manawa like, ua huki ʻia ka ʻili o ka PTFE e hana i kahi papa i hoʻonohonoho ʻia.
Loaʻa i nā ʻili ʻelua e pili ana i kēia manawa nā molekala PTFE i hoʻonohonoho pono ʻia e hiki ke paheʻe ma luna o kekahi
ʻO ka mea i luna nei ka hoʻolauna ʻana o ka polytetrafluoroethylene, hiki ke hana ʻia ka polytetrafluoroethylene i nā ʻano huahana like ʻole, ua loea mākou i ka hana ʻana i ka paipu ptfe、nā mea hana hose ptfe, e ʻoluʻolu e kamaʻilio me mākou
Nā hulina e pili ana i ka hose ptfe:
Ka manawa hoʻouna: Mei-05-2021