Kaʻina hana o PTFE

Ua hoʻomākaukau mua ʻia ʻo Tetrafluoroethylene i ka makahiki 1933. Hoʻokumu ʻia ka synthesis kalepa o kēia manawa ma luna o fluorspar, sulfuric acid a me chloroform.

Kaʻina hana kumu o ka PTFE Polymer:

Hana ʻia ka hana ʻana o ka PTFE Polymer / Resin i ʻelua mau pae.ʻO ka mea mua, hana ʻia ʻo TFE Monomer e ka synthesis o Calcium Fluoride (Fluorospar), Sulfuric Acid & Chloroform & hope polymerization o TFE e lawe ʻia i nā kūlana mālama pono e hana i ka PTFE.Ma muli o ka loaʻa ʻana o nā paʻa CF paʻa a paʻa, loaʻa ka molekala PTFE i ka inertness kemika koʻikoʻi, ke kūpaʻa wela kiʻekiʻe a me nā hiʻohiʻona insulation uila;ma waho aʻe o nā waiwai frictional maikaʻi loa.

Hoʻomaʻemaʻe i ka TFE:

Pono ka monomer maʻemaʻe no ka polymerization.Inā loaʻa nā haumia e pili ana i ka huahana hope.Holoi mua ʻia ke kinoea no ka wehe ʻana i ka waika hydrochloric a laila hoʻomaʻemaʻe ʻia e hoʻokaʻawale i nā mea haumia ʻē aʻe.

Polymerization o TFE:

Hiki i ka Tetrafluoroethylene maʻemaʻe ʻole i hoʻopaʻa ʻia ke polymerise me ka hana ʻino, ʻoiai ma nā mahana ma lalo o ka mahana o ka lumi.ʻO kahi reactor i hoʻopaʻa ʻia i ke kālā, hoʻopiha ʻia i ka hapaha me kahi hopena i loaʻa he 0.2 ʻāpana ammonium persulphate, 1.5 ʻāpana borax a me 100 mau ʻāpana wai, a me ka pH o 9.2.Ua pani ʻia ka reactor;Ua hoʻokuʻu ʻia a hoʻokuʻu ʻia nā ʻāpana 30 o ka monomer. Ua hoʻonāukiuki ʻia ka reactor no hoʻokahi hola ma 80 ° C a ma hope o ka hoʻoluʻu ʻana ua hāʻawi ʻia he 86% o ka polymer. Ua hana ʻia ʻo PTFE ma ke kālepa ʻana e ʻelua kaʻina hana nui, kahi alakaʻi i ka mea i kapa ʻia 'granular' polymer a me ka lua e alakaʻi ana i ka hoʻopuehu ʻana o ka polymer ʻoi aku ka maikaʻi o ka nui o ka nui a me ke kaumaha molekala haʻahaʻa.Hoʻokahi ʻano hana o ka hana ʻana i ka mea hope e pili ana i ka hoʻohana ʻana i kahi solution 0.1°% aqueous disuccinic acid peroxide.Ua hana ʻia nā hopena ma ka mahana a hiki i 90 ° C.

Nā hana ʻē aʻe:

Decomposition o TFE ma lalo o ka mana o ka uila arc.Polymerization i laweia e ka emulsion me ka hoʻohana peroxide initiators e laʻa me H2O2 (Hydrogen peroxide) a me ferrous sulphate.I kekahi mau hihia, hoʻohana ʻia ka oxygen i mea hoʻomaka.

ʻO ke ʻano a me nā waiwai o PTFE:

ʻO ka hana kemika o PTFE he polymer linear o C– F2 – C– F2 me ka ʻole o kekahi lālā & nā waiwai koʻikoʻi o PTFE e pili pū ana i ka paʻa Carbon - Fluorine paʻa.

ʻO ka Polytetrafluoroethylene kahi polymer linear me ka ʻole o ka nui o ka lālā.Oiai ka mole o ka polyethylene ma ke ano o ka planar zigzag i ka crystalline zone keia sterically hiki ole me ka PTFE ma muli o ka fluorine atoms oi aku mamua o ka hydrogen.No laila, lawe ka mole i kahi zigzag wili me nā ʻātoma fluorine e hoʻopaʻa paʻa ana i loko o kahi ʻōniʻoniʻo a puni ka iwi carbon-carbon.ʻO ka huli holoʻokoʻa o ka spiral e komo ma luna o 26 carbon atoms ma lalo o 19°C a me 30°C ma luna o laila aia kahi wahi hoʻololi e pili ana i ka hoʻololi leo 1% i kēia mahana.ʻO ka hoʻopili paʻa ʻana o nā ʻātoma fluorine e alakaʻi i kahi mole o ka ʻoʻoleʻa nui a ʻo ia kēia hiʻohiʻona e alakaʻi ai i ka helu hoʻoheheʻe crystalline kiʻekiʻe a me ka paʻa ʻana o ke ʻano wela o ka polymer.

He liʻiliʻi loa ka hukihuki intermolecular ma waena o nā molekala PTFE, ʻo ka ʻāpana solubility i helu ʻia ʻo 12.6 (MJ/m3) 1/2 ʻAʻole i loaʻa i ka polymer i ka nui ka rigidity kiʻekiʻe a me ka ikaika tensile i pili pinepine me nā polymers me kahi wahi palupalu kiʻekiʻe.Paʻa loa ka paʻa kalapona-fluorine.Eia kekahi, ma kahi i hoʻopili ʻia ai nā ʻātoma fluorine ʻelua i ka ʻātoma kalapona hoʻokahi, aia ka hoʻemi ʻana o ka mamao pili C-F mai 1.42 A a i 1.35 A. ʻO ka hopena, hiki ke kiʻekiʻe o nā ikaika pili i 504 kJ/mole.No ka mea, ʻo ka mea paʻa ʻē aʻe wale nō ka paʻa C–C paʻa, he kiʻekiʻe loa ka wela o ka PTFE, ʻoiai ke wela ʻana ma luna o kona wahi hoʻoheheʻe crystalline o 327°C.Ma muli o kona crystallinity kiʻekiʻe a me ka hiki ʻole o ka launa pū ʻana, ʻaʻohe mea hoʻoheheʻe ma ka lumi wela.Ma nā mahana e kokoke ana i ka helu heheʻe, e hoʻoheheʻe kekahi mau wai fluorinated e like me per-fluorinated kerosene i ka polymer.

Aia nā waiwai o ka PTFE i ke ʻano o ka polymer a me ke ʻano o ka hana.He ʻokoʻa paha ka polymer i ka nui o ka ʻāpana a/a i ke kaumaha molekala.ʻO ka nui o ka ʻāpana e hoʻololi i ka hihia o ka hoʻoponopono ʻana a me ka nui o nā puka i loko o ka huahana i hoʻopau ʻia aʻo ka paona molekala e hoʻololi i ka crystallinity a no laila nā waiwai kino.E pili pū ana nā ʻenehana hana i ka crystallinity a me ka ʻike ʻole.

ʻO ke kaumaha o ke kaumaha o nā polymers pāʻoihana eʻikeʻia he kiʻekiʻe loa a aia ma ka laulā 400000 a hiki i ka 9000000. ICI hōʻike i kā lākou mau mea i ke kaumaha mole ma ka laulā 500000 a hiki i ka 5000000 a me ka pakeneka crystallinity nui ma mua o 94 ~ e like me ka mea i hanaʻia.ʻO nā ʻāpana i hana ʻia he liʻiliʻi crystalline.ʻO ke kiʻekiʻe o ka crystallinity o ka huahana i hoʻopau ʻia e hilinaʻi ʻia ma ka wikiwiki o ka hoʻoilo mai nā mahana hana.ʻO ka hoʻomaha mālie e alakaʻi i ka crystallinity kiʻekiʻe me ka hoʻomaha wikiwiki e hāʻawi i ka hopena kū'ē.E ʻoi aku ka crystalline haʻahaʻa haʻahaʻa molekala kaumaha.

ʻIke ʻia ʻo ka dispersion polymer, ʻoi aku ka ʻoi aku o ka nui o ka ʻāpana a me ke kaumaha molekala haʻahaʻa, hāʻawi i nā huahana me ka hoʻomaikaʻi maikaʻi ʻana i ke kūʻē ʻana i ka flexing a ʻoi aku hoʻi ka ikaika tensile kiʻekiʻe.ʻIke ʻia kēia mau hoʻomaikaʻi ʻana ma o ka hoʻokumu ʻana i nā hale e like me ka fiber i ka nui o ka polymer i ka wā e hana ai.