Pehea e ʻike ai i ka kiʻiʻoniʻoni PE a me ke kiʻiʻoniʻoni PVC i kahi ala maʻamau a i ʻole kēlā me kēia lā?
ʻO ka mea āu e ʻimi nei ʻo ka hōʻike Beilstein.Hoʻoholo ia i ka hele ʻana o PVC ma ka ʻike ʻana i ke alo o ka chlorine.Pono ʻoe i ka lama propane (a i ʻole Bunsen kuni) a me ka uea keleawe.ʻAi maʻemaʻe ka uea keleawe akā ke hui pū ʻia me kahi mea i loaʻa i ka chlorine (PVC) ʻōmaʻomaʻo.E hoʻopaʻa i kahi uwea keleawe ma luna o ka lapalapa (e hoʻohana i nā pliers e pale iā ʻoe iho a hoʻohana i kahi uea lōʻihi) e wehe i ke koena makemake ʻole.E kaomi i ka uea wela i kāu la'ana i'a i hehe'e kekahi o ia mea ma ka uea a laila e pani i ka uea i uhi 'ia ma luna o ka lapalapa a e nānā i ka 'ōma'oma'o'ōma'oma'o.Inā 'aʻa ka ʻōmaʻomaʻo ʻōmaʻomaʻo, loaʻa iā ʻoe ka PVC.
ʻO ka hope loa, ʻaʻā ʻo PE me ka ʻala e like me ka wax ʻaʻa a ʻo ka PVC he ʻala kemika nui loa a pio koke iā ia iho i ka wā i lawe ʻia mai kahi lapalapa.
"Ua like anei ka polyethylene me PVC?"ʻAʻole.
ʻAʻohe chlorine o ka polyethylene i loko o ka mole, ʻo PVC.ʻO ka PVC kahi polyvinyl-substituted chlorine, ʻaʻole polyethylene.ʻOi aku ka paʻakikī o PVC ma mua o ka polyethylene.ʻOi aku ka nui o ka CPVC.Hoʻopili ʻo PVC i ka wai i loko o ka wai i ka wā ʻona, ʻaʻole polyethylene.Nahaha ka PVC ma lalo o ka overpressure (no laila, ʻaʻole kūpono no ka hoʻohana ʻana i ka ea compressed), ʻaʻole polyethylene.
ʻO nā mea ʻelua i thermoformed plastics.
He polyethylene ka PVC?
ʻO PVC, a i ʻole polyvinyl chloride, he polyethylene i pani ʻia.ʻO ia hoʻi, ʻo kēlā me kēia kalapona ʻē aʻe o ke kaulahao hoʻokahi chlorine i hoʻopili ʻia me kahi hydrogen, ma mua o nā hydrogens ʻelua i loaʻa mau ma ka polyethylene.
He aha ka polyethylene plastic i hana ʻia mai?
Ethylene
ʻO ka Polyethylene (PE), māmā a me ka versatile synthetic resin i hana ʻia mai ka polymerization o ka ethylene.ʻO ka polyethylene kekahi lālā o ka ʻohana koʻikoʻi o nā resins polyolefin.
He aha ka polyethylene pili kea?
ʻO ka polyethylene kahi hydrocarbon kaulahao lōʻihi i hana ʻia e ka hoʻopili ʻana o nā molekole ethylene i loko o kahi pane i kapa ʻia he polymerization.Aia nā ʻano like ʻole e hoʻokō ai i kēia hopena polymerization.
Inā hoʻohana ʻia kahi catalyst inorganic e pili ana iā Ti (Ziegler polymerization), maʻalahi nā ʻano hopena a ʻo ka polymer ka hopena ma ke ʻano o nā kaulahao hydrocarbon saturated lōʻihi loa me ka liʻiliʻi loa o ka unsaturation (un-saturated -CH=CH2 pūʻulu) ma ke ʻano he ʻāpana. o ke kaulahao a i ole ma ke ano he hui lele.Ua kapa ʻia kēia huahana ʻo High Density Polyethylene (HDPE).ʻOiai ke hoʻokomo ʻia nā co-monomers e like me 1-butene, ʻoi aku ka liʻiliʻi o ke kiʻekiʻe o ka unsaturation i ka polymer hopena (LLDPE).
Inā hoʻohana ʻia kahi mea hoʻoheheʻe inorganic ma muli o Chromium Oxide, ua hoʻokumu hou ʻia nā kaulahao hydrocarbon laina lōʻihi, akā ʻike ʻia kekahi pae o ka unsaturation.ʻO HDPE hou kēia, akā me ka lālā kaulahao lōʻihi.
Inā mālama ʻia ka polymerization i hoʻomaka ʻia, aia kahi manawa no nā kaulahao ʻaoʻao lōʻihi ʻelua i loko o ka polymer, a me kekahi mau wahi o nā pūʻulu unsaturated -CH=CH2 ma ke ʻano o ke kaulahao.Ua kapa ʻia kēia resin he LDPE.Hiki ke hoʻohui ʻia kekahi mau co-monomers e like me vinyl acetate, 1-butene a me nā dienes e hoʻololi a hoʻohana i ke kaulahao hydrocarbon, a hoʻokomo pū kekahi i ka unsaturation hou i nā pūʻulu lele.
ʻO LDPE, no kona kiʻekiʻe kiʻekiʻe o ka maʻiʻo unsaturation, ka mea nui no ka hoʻopili ʻana.He hana kēia ma hope o ka hoʻomākaukau ʻana o ka polymer linear mua.Ke hui pū ʻia ʻo LDPE me nā mea hoʻomaka radical manuahi ma nā wela kiʻekiʻe, hoʻopili ia i nā kaulahao like ʻole ma o ka "cross-linking" ma o.na kaulahao aoao unsaturated.ʻO kēia ka hopena i kahi hoʻolālā tertiary (3-dimensional structure) i ʻoi aku ka "paʻa".
Hoʻohana ʻia nā hopena crosslinking e "hoʻonohonoho" i kahi ʻano kikoʻī, ma ke ʻano he paʻa a i ʻole he ʻūhā, e hoʻomaka ana me ka polymer pliable a maʻalahi.Hoʻohana ʻia ke kaʻina hana like o ka crosslinking i ka "vulcanization" o ka rubber, kahi i hana ʻia ai kahi polymer linear i hana ʻia mai ka polymerization isoprene i loko o kahi ʻano paʻa 3-dimensional me ka hoʻohana ʻana i ka sulfur (S8) ma ke ʻano he mea hana e hoʻopaʻa i nā kaulahao like ʻole.Hiki ke ho'omalu 'ia ke degere o ka ho'opili 'ana no ka hā'awi 'ana i nā pahuhopu kiko'ī i nā waiwai o ka polymer hopena.
Ka manawa hoʻouna: Oct-11-2022