Polyethylene (PE)
1. Hana o PE
ʻO PE ka plastic i hana nui ʻia ma waena o nā plastics, me ka mānoanoa ma kahi o 0.94g/cm3. Hōʻike ʻia ʻo ia e ka translucent, palupalu, non-toxic, cheap, a maʻalahi hoʻi e hana. ʻO ka PE he polymer crystalline maʻamau a loaʻa iā ia ka hanana post-shrinkage. Nui nā ʻano o ia mea, ʻo ka mea maʻamau ʻo LDPE i ʻoi aku ka palupalu (i ʻike pinepine ʻia ʻo ka ʻōpala palupalu a i ʻole nā mea pua pua), HDPE i ʻike mau ʻia ʻo ka ʻōpala palupalu paʻakikī, ʻoi aku ka paʻakikī ma mua o ka LDPE, ʻaʻohe o ka transmittance māmā a me ka crystallinity kiʻekiʻe. ; He hana maikaʻi loa ko LLDPE, e like me nā plastics engineering. He kūpaʻa kemika maikaʻi ka PE, ʻaʻole maʻalahi ke ʻino, a paʻakikī ke paʻi. Pono e oxidized ka ʻili ma mua o ka paʻi ʻana.
2. Noi o PER
HDPE: ʻeke ʻeke plastik, nā mea e pono ai i kēlā me kēia lā, nā bākeke, nā uea, nā mea pāʻani, nā mea kūkulu hale, nā ipu.
LDPE: ʻeke ʻeke plastik, nā pua plastik, nā mea pāʻani, nā uea kiʻekiʻe, nā mea kākau, etc.
3. Nā hiʻohiʻona kaʻina hana PE
ʻO ka hiʻohiʻona kaulana loa o nā ʻāpana PE ʻo ia ka nui o ka shrinkage molding rate a hiki i ka shrinkage a me ka deformation. He haʻahaʻa ka wai o nā mea PE a ʻaʻole pono e hoʻomaloʻo. Loaʻa i ka PE kahi ākea ākea o ka hoʻoponopono ʻana a ʻaʻole maʻalahi ka decompose (ʻo ka mahana decomposition ma kahi o 300 ° C). ʻO ka mahana o ka hana ʻana he 180 a 220 ° C. Inā kiʻekiʻe ke kaomi injection, e kiʻekiʻe ka nui o ka huahana a e liʻiliʻi ka wikiwiki. Loaʻa ka wai maʻamau o ka PE, no laila pono e lōʻihi ka manawa paʻa a mālama mau ʻia ka mahana o ka mold (40-70 ° C).
ʻO ka degere o ka crystallization o PE pili i nā kūlana kaʻina hana. Loaʻa iā ia kahi mahana solidification kiʻekiʻe. ʻO ka haʻahaʻa o ka mahana mold, ʻoi aku ka haʻahaʻa o ka crystallinity. . I ka wā o ka crystallization kaʻina hana, ma muli o ka anisotropy o ka shrinkage, hoʻokumu ʻia ke koʻikoʻi koʻikoʻi o loko, a ua maʻalahi nā ʻāpana PE i ka deform a me ka haki. ʻO ka waiho ʻana i ka huahana i loko o ka ʻauʻau wai i ka wai wela 80 ℃ hiki ke hoʻomaha i ke koʻikoʻi o loko i kekahi ʻano. I ka wā o ke kaʻina hana, pono e ʻoi aku ka kiʻekiʻe o ka mahana ma mua o ka mahana o ka mold. Pono e haʻahaʻa ka paʻi injection me ka hōʻoia ʻana i ka maikaʻi o ka ʻāpana. ʻO ka hoʻomaloʻo ʻana o ka ʻōpala e koi nui ʻia e wikiwiki a me ke ʻano, a e wela ka huahana i ka wā i hoʻoheheʻe ʻia.
Polypropylene (PP)
1. Hana o PP
ʻO PP kahi polymer crystalline me ka nui o 0.91g/cm3 (emi iho i ka wai). ʻO PP ka māmā ma waena o nā plastic i hoʻohana mau ʻia. Ma waena o nā plastic plastics, ʻoi aku ka maikaʻi o ka pale ʻana o ka wela, me kahi mahana deformation wela o 80 a 100 ° C a hiki ke hoʻolapalapa ʻia i ka wai paila. Loaʻa i ka PP ke koʻikoʻi koʻikoʻi ke kūʻē a me ke ola luhi luhi, a ʻike ʻia ʻo "100% plastic". ".
ʻOi aku ka maikaʻi o ka hana piha o ka PP ma mua o nā mea PE. ʻO nā huahana PP he māmā, paʻakikī a paʻa i nā kemika. ʻO nā hemahema o ka PP: ka haʻahaʻa haʻahaʻa pololei, lawa ʻole ka rigidity, ke kū ʻana o ka wā maikaʻi ʻole, maʻalahi ka hana ʻana i ka "pōʻino keleawe", loaʻa iā ia ka hanana post-shrinkage, a ʻoi aku ka maikaʻi o nā huahana i ka wā kahiko, lilo i brittle a deformed.
2. Noi o PP
Nā mea like ʻole o ka hale, nā poʻi ipu hao, nā paipu lawe kemika, nā ipu kemika, nā lako lapaʻau, nā mea hana, nā mea pāʻani, nā filament, nā kīʻaha wai, nā pahu huli, nā paipu, nā hinges, etc.
3. Kaʻina hana o PP:
Loaʻa ka wai maikaʻi o ka PP ma ka wela hoʻoheheʻe a me ka hana hoʻoheheʻe maikaʻi. ʻElua mau hiʻohiʻona o ka PP:
ʻO ka mea mua: e emi nui ana ka viscosity o PP melt me ka piʻi ʻana o ka shear rate (emi ʻia e ka mahana);
ʻO ka lua: He kiʻekiʻe ke kiʻekiʻe o ka orientation molecular a nui ka nui o ka emi ʻana.
ʻOi aku ka maikaʻi o ka mahana hana o PP ma kahi o 200 ~ 250 ℃. Loaʻa iā ia ke kūpaʻa wela maikaʻi (ʻo 310 ℃ ka wela decomposition), akā i ka mahana kiʻekiʻe (280 ~ 300 ℃), hiki ke hoʻohaʻahaʻa inā noho ia i loko o ka pahu no ka manawa lōʻihi. Ma muli o ka emi nui o ka viscosity o PP me ka piʻi ʻana o ka shear rate, ʻo ka hoʻonui ʻana i ke kaomi injection a me ka wikiwiki o ka injection e hoʻomaikaʻi i kona wai; no ka hoʻomaikaʻi ʻana i ka deformation shrinkage a me nā dents, pono e hoʻomalu ʻia ka mahana mold ma waena o 35 a 65 ° C. ʻO ka mahana crystallization he 120 ~ 125 ℃. Hiki i ka hoʻoheheʻe PP ke hele i loko o kahi āwaha ololi loa a hana i kahi ʻoi ʻoi. I ka wā o ka hoʻoheheʻe ʻana, pono ʻo PP e komo i ka nui o ka wela hoʻoheheʻe (ʻoi aku ka nui o ka wela kikoʻī), a e wela ka huahana ma hope o ka puka ʻana i waho o ka mold. ʻAʻole pono e hoʻomaloʻo ʻia nā mea PP i ka wā o ka hana ʻana, a ʻoi aku ka haʻahaʻa o ka shrinkage a me ka crystallinity o PP ma mua o ka PE.
Ka manawa hoʻouna: Dec-28-2023