Hoʻohālikelike o LLDPE a me LDPE .

Linear haʻahaʻa haʻahaʻa polyethylene, structurally ʻokoʻa mai ka laulā haʻahaʻa haʻahaʻa polyethylene, no ka mea, ʻaʻohe lālā kaulahao lōʻihi. ʻO ka linearity o LLDPE e pili ana i nā ʻano hana like ʻole a me nā kaʻina hana o LLDPE a me LDPE. Hoʻokumu pinepine ʻia ʻo LLDPE e ka copolymerization o ka ethylene a me nā alpha olefins kiʻekiʻe e like me butene, hexene a i ʻole octene ma ka haʻahaʻa haʻahaʻa a me ke kaomi. ʻO ka polymer LLDPE i hana ʻia e ke kaʻina hana copolymerization he haʻihaʻi kaumaha molecular ma mua o LDPE maʻamau, a ma ka manawa like he ʻano laina laina e loaʻa ai iā ia nā waiwai rheological ʻokoʻa.

waiwai kahe hehee

Hoʻololi ʻia nā ʻano kahe kahe o LLDPE i nā koi o ke kaʻina hana hou, ʻoi aku ka nui o ke kaʻina extrusion kiʻiʻoniʻoni, hiki ke hana i nā huahana LLDPE kiʻekiʻe. Hoʻohana ʻia ʻo LLDPE ma nā mākeke kuʻuna āpau no ka polyethylene. ʻO ka hoʻonui ʻia ʻana, ke komo ʻana, ka hopena a me nā waiwai kūʻē i ka waimaka e kūpono iā LLDPE no nā kiʻiʻoniʻoni. ʻO kona kūpaʻa maikaʻi ʻana i ke koʻikoʻi koʻikoʻi o ke kaiapuni, ka haʻahaʻa haʻahaʻa haʻahaʻa haʻahaʻa haʻahaʻa a me ka pale kaua ʻana i ka LLDPE e nani ai no ka paipu, ka extrusion pepa a me nā noi hana a pau. ʻO ka noi hou loa o LLDPE he mulch no nā pae ʻāina a me nā linings no nā loko ʻōpala.

Hana a me nā ʻano

Hoʻomaka ka hana ʻana o LLDPE me nā catalyst metala hoʻololi, ʻoi aku ka nui o ke ʻano Ziegler a i ʻole Phillips. ʻO nā kaʻina hana hou e pili ana i ka cycloolefin metal derivative catalysts kahi koho ʻē aʻe no ka hana LLDPE. Hiki ke ho'okō 'ia ka hopena polymerization maoli i loko o ka hā'ina a me nā reactors ma ke kinoea. Hoʻopili ʻia ka Hexene a me ka ethylene i loko o kahi reactor. ʻO ka resina LLDPE i hana ʻia i loko o ka reactor phase gas ma ke ʻano particulate a hiki ke kūʻai ʻia ma ke ʻano he pauka a i ʻole e hana hou ʻia i pellets. Ua hoʻomohala ʻia kahi hanauna hou o super LLDPE e pili ana i ka hexene a me ka octene e Mobile, Union Carbide. Hoʻokuʻu ʻia nā ʻoihana e like me Novacor a me Dow Plastics. He palena paʻakikī nui kēia mau mea a loaʻa iā ia ka mana hou no nā noi wehe ʻeke ʻakomi. Ua ʻike ʻia ka haʻahaʻa haʻahaʻa haʻahaʻa PE resin (density ma lalo o 0.910g/cc.) i nā makahiki i hala. Loaʻa iā VLDPES ka maʻalahi a me ka palupalu i hiki ʻole iā LLDPE ke hoʻokō. Hōʻike ʻia nā waiwai o nā resins i ka melt index a me ka density. Hōʻike ka melt index i ka awelika molecular paona o ka resin a ua hoʻomalu mua ʻia e ka wela o ka hopena. Kūʻokoʻa ke kaumaha molekala maʻamau i ka puʻunaue kaumaha molekala (MWD). Pili ke koho Catalyst i ka MWD. Hoʻoholo ʻia ka Density e ka neʻe ʻana o ka comonomer i ke kaulahao polyethylene. Hoʻoponopono ka comonomer i ka helu o nā lālā kaulahao pōkole (ʻo ka lōʻihi e pili ana i ke ʻano comonomer) a pēlā e hoʻomalu ai i ka nui o ka resin. ʻOi aku ka kiʻekiʻe o ka comonomer, ʻoi aku ka haʻahaʻa o ka nui o ka resin. ʻOkoʻa ka LLDPE me ka LDPE ma ka helu a me ke ʻano o nā lālā, he mau lālā lōʻihi ka LDPE kiʻekiʻe, aʻo ka LDPE laina he mau lālā pōkole wale nō.

hana ʻana

Loaʻa ka LDPE a me ka LLDPE i ka rheology maikaʻi a i ʻole ke kahe hehee. ʻAʻole liʻiliʻi ka naʻau o ka LLDPE ma muli o kona puʻunaue kaumaha molekala haiki a me nā lālā kaulahao pōkole. I ka wā ʻako (e laʻa me ka extrusion), paʻa ka LLDPE i ka viscosity ʻoi aʻe a no laila ʻoi aku ka paʻakikī o ka hana ʻana ma mua o LDPE me ka helu hehee hoʻokahi. Ma ka extrusion, hiki i ka LLDPE ka hoʻohaʻahaʻa haʻahaʻa haʻahaʻa no ka hoʻomaha ʻana i ke koʻikoʻi o nā kaulahao polymer molecular, a no laila ka emi ʻana o ka naʻau o nā waiwai kino i ka hoʻololi ʻana i ka ratio blow-up. I ka hoʻonui heheʻe, ʻokoʻa ka LLDPE ma lalo o nā ʻano like ʻole. ʻO ia hoʻi, ʻaʻole ia e hoʻopaʻa i ka paʻakikī ke hoʻopaʻa ʻia e like me LDPE. E hoʻonui me ka helu deformation o polyethylene. Hōʻike ka LDPE i ka piʻi nui ʻana o ka viscosity, ka mea i hoʻopili ʻia e nā kaulahao molekala. ʻAʻole ʻike ʻia kēia hanana ma LLDPE no ka mea ʻo ka nele o nā lālā kaulahao lōʻihi i LLDPE e mālama i ka polymer mai ka hoʻopili ʻana. He mea koʻikoʻi kēia waiwai no nā noi kiʻiʻoniʻoni lahilahi. No ka mea hiki i nā kiʻiʻoniʻoni LLDPE ke hana maʻalahi i nā kiʻi ʻoniʻoni ʻoi aku ka ʻoi aku ka ikaika a me ka paʻakikī. Hiki ke hōʻuluʻulu ʻia nā waiwai rheological o LLDPE ma ke ʻano he "rigid in shear" a me "soft in extension".