Nā ʻAno Hana a me nā ʻAno like ʻole o ka Polyethylene Synthesis
(1) Polyethylene Haʻahaʻa-Density (LDPE)
Ke hoʻohui ʻia nā ʻāpana liʻiliʻi o ka oxygen a i ʻole nā peroxides ma ke ʻano he mea hoʻomaka i ka ethylene maʻemaʻe, i hoʻopaʻa ʻia i kahi 202.6 kPa, a hoʻomehana ʻia i kahi 200°C, hoʻopili ka ethylene i loko o ka polyethylene keʻokeʻo, waxy. Ua kapa pinepine ʻia kēia ʻano hana ʻo ke kaʻina hana kiʻekiʻe ma muli o nā kūlana hana. ʻO ka polyethylene hopena he density o 0.915–0.930 g/cm³ a me ke kaumaha molekala mai 15,000 a 40,000. He lālā nui a wehe ʻia kona ʻano molekala, e like me ke ʻano "lāʻau", ʻo ia hoʻi kona density haʻahaʻa, no laila ka inoa low-density polyethylene.
(2) Polyethylene Waena-Density (MDPE)
ʻO ke kaʻina hana kaomi waena e pili ana i ka polymerizing ethylene ma lalo o 30-100 mau lewa me ka hoʻohana ʻana i nā mea hoʻouluulu oxide metala. ʻO ka polyethylene hopena he density o 0.931-0.940 g/cm³. Hiki ke hana ʻia ka MDPE ma ke kāwili ʻana i ka polyethylene density kiʻekiʻe (HDPE) me LDPE a i ʻole ma o ka copolymerization o ka ethylene me nā comonomers e like me butene, vinyl acetate, a i ʻole acrylates.
(3) Polyethylene Paʻa Kiʻekiʻe (HDPE)
Ma lalo o nā kūlana mahana a me ke kaomi maʻamau, ua polymerized ʻia ka ethylene me ka hoʻohana ʻana i nā mea hoʻouluulu hoʻohui maikaʻi loa (nā hui organometallic i haku ʻia me ka alkylaluminum a me ka titanium tetrachloride). Ma muli o ka hana catalytic kiʻekiʻe, hiki ke hoʻopau koke ʻia ka hopena polymerization ma nā kaomi haʻahaʻa (0-10 atm) a me nā mahana haʻahaʻa (60-75°C), no laila ke kaʻina hana haʻahaʻa. ʻO ka polyethylene hopena he ʻano molekala linear ʻole lālā, e hāʻawi ana i kona density kiʻekiʻe (0.941-0.965 g/cm³). Ke hoʻohālikelike ʻia me LDPE, hōʻike ʻo HDPE i ke kūpaʻa wela kiʻekiʻe, nā waiwai mechanical, a me ke kūpaʻa ʻana i ka stress-cracking o ke kaiapuni.
Nā Waiwai o ka Polyethylene
He ʻano keʻokeʻo waiū ka polyethylene, e like me ka wax, semi-transparent, e lilo ia i mea hoʻomehana kūpono a me ka uhi no nā uea a me nā kaula. ʻO kona mau pono nui:
(1) Nā waiwai uila maikaʻi loa: ke kū'ē'ē kiʻekiʻe o ka insulation a me ka ikaika dielectric; haʻahaʻa ka permittivity (ε) a me ka dielectric loss tangent (tanδ) ma kahi ākea ākea, me ka liʻiliʻi o ka hilinaʻi alapine, e lilo ia i dielectric kūpono no nā kaula kamaʻilio.
(2) Nā waiwai mechanical maikaʻi: palupalu akā paʻakikī, me ke kūpaʻa maikaʻi i ka deformation.
(3) Ke kūpaʻa ikaika i ka ʻelemakule wela, ka brittleness haʻahaʻa, a me ke kūpaʻa kemika.
(4) Kūpaʻa wai maikaʻi loa me ka omo haʻahaʻa o ka makū; ʻaʻole emi ka pale ʻana o ka insulation i ka wā e hoʻokomo ʻia ai i loko o ka wai.
(5) Ma ke ʻano he mea non-polar, hōʻike ia i ka permeability kinoea kiʻekiʻe, me LDPE ka mea i loaʻa ka permeability kinoea kiʻekiʻe loa ma waena o nā plastics.
(6) Haʻahaʻa ke kaumaha kikoʻī, ma lalo o 1. ʻIke nui ʻia ka LDPE ma kahi o 0.92 g/cm³, ʻoiai ʻo HDPE, ʻoiai kona nui o ka density, aia wale nō ma kahi o 0.94 g/cm³.
(7) Nā waiwai hana maikaʻi: maʻalahi ke hoʻoheheʻe a me ka plasticize me ka ʻole o ka palaho ʻana, hoʻomaʻalili koke i ke ʻano, a hiki ke hoʻomalu pololei i ke ʻano huahana a me nā ana.
(8) He māmā nā kaula i hana ʻia me ka polyethylene, maʻalahi ke kau ʻana, a maʻalahi hoʻi e hoʻopau. Eia nō naʻe, he nui nā hemahema o ka polyethylene: ka mahana palupalu haʻahaʻa; hiki ke lapalapa, e hoʻopuka ana i kahi ʻala paraffin i ka wā e puhi ʻia ai; kūpaʻa maikaʻi ʻole i ke kaiapuni a me ke kūpaʻa kolo. Pono ka nānā kūikawā i ka wā e hoʻohana ai i ka polyethylene ma ke ʻano he insulation a i ʻole sheathing no nā kaula submarine a i ʻole nā kaula i hoʻokomo ʻia i nā hāʻule kū pololei.
Nā Plastics Polyethylene no nā Uea a me nā Kaula
(1) Palekana Polyethylene Hoʻokaʻawale Hana Laulā
I hana ʻia wale nō me ka polyethylene resin a me nā antioxidants.
(2) Palakiko Polyethylene Pale i ke Anu
Hana nui ʻia me ka resin polyethylene, nā antioxidants, a me ke kalapona ʻeleʻele. Pili ke kūpaʻa ʻana o ka wā i ka nui o nā ʻāpana, ka nui, a me ka hoʻopuehu ʻana o ke kalapona ʻeleʻele.
(3) Plastika Polyethylene Pale i ke Kaiapuni mai ka Māwae a me ka Nahā
Hoʻohana i ka polyethylene me kahi helu kahe heheʻe ma lalo o 0.3 a me kahi hoʻolaha kaumaha molekala haiki. Hiki ke hoʻopili ʻia ka polyethylene ma o ka irradiation a i ʻole nā ʻano kemika.
(4) Palekana Polyethylene Hoʻokaʻawale Uila Kiʻekiʻe
Pono ka pale ʻana o ke kaula uila kiʻekiʻe i ka polyethylene plastic maʻemaʻe loa, i hoʻohui ʻia me nā mea hoʻopaʻa uila a me nā extruders kūikawā e pale i ka hoʻokumu ʻana o ka hakahaka, kāohi i ka hoʻokuʻu ʻana o ka resin, a hoʻomaikaʻi i ke kūpaʻa ʻana o ka arc, ke kūpaʻa ʻana i ka ʻino uila, a me ke kūpaʻa ʻana i ka corona.
(5) Plastika Polyethylene Semiconductor
Hana ʻia ma ka hoʻohui ʻana i ke kalapona ʻeleʻele conductive i ka polyethylene, maʻamau me ka hoʻohana ʻana i ka ʻeleʻele kalapona ʻano kiʻekiʻe, nā ʻāpana maikaʻi.
(6) Hui Uea Polyolefin Thermoplastic Low-Smoke Zero-Halogen (LSZH)
Hoʻohana kēia hui i ka resin polyethylene ma ke ʻano he mea kumu, e hoʻohui pū ana i nā mea pale ahi halogen-free kiʻekiʻe, nā mea hoʻopau uahi, nā mea hoʻopaʻa wela, nā mea antifungal, a me nā mea hoʻoluʻu, i hana ʻia ma o ke kāwili ʻana, plasticization, a me ka pelletization.
Polyethylene i hoʻopili ʻia (XLPE)
Ma lalo o ka hana a ka radiation ikehu kiʻekiʻe a i ʻole nā mea crosslinking, hoʻololi ke ʻano molekala linear o ka polyethylene i loko o kahi ʻano ʻekolu-dimensional (pūnaewele), e hoʻololi ana i ka mea thermoplastic i loko o kahi thermoset. Ke hoʻohana ʻia e like me ka insulation,XLPEhiki ke kū i nā mahana hana mau a hiki i ka 90°C a me nā mahana pōkole o 170–250°C. ʻO nā ʻano hana crosslinking e komo pū me ke crosslinking kino a me ke kemika. ʻO ke crosslinking irradiation kahi ʻano kino, ʻoiai ʻo ka mea hana crosslinking kemika maʻamau ʻo DCP (dicumyl peroxide).
Ka manawa hoʻouna: ʻApelila-10-2025