Nūhou

Introduction to Polyolefins and Film Extrusion

ʻO nā polyolefins, kahi papa o nā mea macromolecular i hoʻohui ʻia mai nā monomer olefin e like me ka ethylene a me propylene, ʻo ia ka mea i hana nui ʻia a hoʻohana ʻia i nā plastics ma ka honua holoʻokoʻa. Loaʻa ko lākou laha ʻana mai kahi hui kūʻokoʻa o nā waiwai, me ke kumu kūʻai haʻahaʻa, ka hana maikaʻi loa, ke kūpaʻa kemika maikaʻi, a me nā ʻano kino kūpono. Ma waena o nā noi like ʻole o nā polyolefins, paʻa nā huahana kiʻiʻoniʻoni i kahi kūlana koʻikoʻi, e lawelawe ana i nā hana koʻikoʻi i ka hoʻopili meaʻai, nā uhi mahiʻai, nā ʻāpana ʻenehana, nā huahana olakino a me ka maʻemaʻe, a me nā mea kūʻai aku i kēlā me kēia lā. ʻO nā resins polyolefin maʻamau i hoʻohana ʻia no ka hana kiʻiʻoniʻoni he polyethylene (PE) - e hoʻopili ana i ka Linear Low-Density Polyethylene (LLDPE), Low-Density Polyethylene (LDPE), a me High-Density Polyethylene (HDPE) - a me ka polypropylene (PP).

ʻO ka hana ʻana o nā kiʻiʻoniʻoni polyolefin e hilinaʻi nui i ka ʻenehana extrusion, me Blown Film Extrusion a me Cast Film Extrusion ʻo ia nā kaʻina hana ʻelua.

1. Puhi Kiʻiʻoniʻoni Extrusion Kaʻina

ʻO ka blown film extrusion kekahi o nā ala maʻamau no ka hana ʻana i nā kiʻiʻoniʻoni polyolefin. ʻO ke kumu kumu e pili ana i ka hoʻokuʻu ʻana i kahi polymer hoʻoheheʻe ʻia i luna ma o ka make annular, e hana ana i kahi parison tubular ʻiliʻili. Ma hope mai, hoʻokomo ʻia ka ea kōmi i loko o kēia parison, e hoʻoulu ai i loko o kahi ʻōpū me ke anawaena ʻoi aku ka nui ma mua o ke anawaena o ka make. I ka piʻi ʻana o ka ʻōhū, hoʻomaʻalili ʻia a hoʻopaʻa ʻia e kahi apo ea waho. Hoʻopau ʻia ka ʻōpū i hoʻomaha ʻia e kahi hui o nā nip rollers (pinepine ma o ke kiʻi hāʻule a i ʻole A-frame) a huki ʻia e nā wili huki ma mua o ka ʻeha ʻana i ka ʻōwili. ʻO ke kaʻina hana kiʻiʻoniʻoni i puhi ʻia e hāʻawi maʻamau i nā kiʻiʻoniʻoni me ka biaxial orientation, ʻo ia hoʻi ke hōʻike nei lākou i ke koena maikaʻi o nā waiwai mechanical ma ka ʻaoʻao ʻelua o ka mīkini (MD) a me ka ʻaoʻao transverse (TD), e like me ka ikaika tensile, ke kūpaʻa waimaka, a me ka ikaika hopena. Hiki ke hoʻomalu ʻia ka mānoanoa kiʻiʻoniʻoni a me nā waiwai mechanical ma o ka hoʻoponopono ʻana i ka lākiō puhi (BUR - ratio o ke anawaena bubble i ke anawaena make) a me ka ratio huki-iho (DDR - ratio o ka wikiwiki lawe i ka wikiwiki extrusion).

2. Kaʻina Kiʻiʻoniʻoni Extrusion

ʻO ka hoʻokuʻu kiʻi kiʻiʻoniʻoni he kaʻina hana koʻikoʻi no nā kiʻiʻoniʻoni polyolefin, kūpono loa no ka hana ʻana i nā kiʻiʻoniʻoni e koi ana i nā waiwai optical ʻoi aku ka maikaʻi (e laʻa, ka mālamalama kiʻekiʻe, kiʻekiʻe gloss) a me ka mānoanoa like ʻole. Ma kēia kaʻina hana, hoʻoheheʻe ʻia ka polymer i hoʻoheheʻe ʻia ma o ka palahalaha, slot-type T-die, e hana ana i kahi pūnaewele hoʻoheheʻe ʻia. A laila, huki koke ʻia kēia pūnaewele ma luna o ka ʻili o hoʻokahi a ʻoi aʻe paha o nā ʻōwili anuanu i hoʻoluʻu ʻia i loko. Paʻa koke ka heheʻe ma ka pili ʻana me ka ʻili ʻōwili anu. Loaʻa i nā kiʻiʻoniʻoni kiʻi ʻoniʻoni maikaʻi loa nā hiʻohiʻona optika maikaʻi loa, ka manaʻo palupalu, a me ka hoʻopaʻa wela maikaʻi. ʻO ka mana pololei ma luna o ka lehelehe make, ke anuanu o ka wela, a me ka wikiwiki o ka hoʻololi ʻana e hiki ai ke hoʻoponopono pololei i ka mānoanoa kiʻiʻoniʻoni a me ka maikaʻi o ka ʻili.

ʻO 6 Nā Pahu Hoʻokuʻu Kiʻiʻoniʻoni ʻO Polyolefin kiʻekiʻe

ʻOiai ke oʻo ʻana o ka ʻenehana extrusion, ʻike pinepine nā mea hana i nā ʻano pilikia o ka hoʻoponopono ʻana i ka hana pono ʻana o nā kiʻiʻoniʻoni polyolefin, ʻoi aku hoʻi i ka wā e hoʻoikaika ai no ka hoʻopuka kiʻekiʻe, ka pono, nā ana lahilahi, a me ka hoʻohana ʻana i nā resins kiʻekiʻe. ʻAʻole pili kēia mau pilikia i ka paʻa ʻana o ka hana akā pili pū kekahi i ka maikaʻi o ka huahana hope a me ke kumukūʻai. Loaʻa nā pilikia nui:

1. ʻO ka ʻeha heheʻe (Sharkskin): ʻO kēia kekahi o nā hemahema maʻamau i ka extrusion kiʻiʻoniʻoni polyolefin. Ma ka Macroscopically, hōʻike ʻia ʻo ia ma ke ʻano he mau nalu transverse a i ʻole he ʻili ʻinoʻino ma luna o ke kiʻiʻoniʻoni, a i ʻole ma nā hihia koʻikoʻi, ʻoi aku ka nui o nā distortions. Hoʻomaka mua ʻia ka haʻihaʻi hoʻoheheʻe i ka wā i ʻoi aku ka nui o ka hoʻoheheʻe ʻana o ka polymer e puka ana i ka make ma mua o ka waiwai koʻikoʻi, e alakaʻi ana i nā oscillations lāʻau-paheʻe ma waena o ka pā make a me ka hehee nui, a i ʻole ke koʻikoʻi hoʻonui i ka puka make ma mua o ka ikaika hehee. Hoʻopilikia loa kēia hemahema i nā waiwai ʻikena o ke kiʻiʻoniʻoni (mālamalama, ʻālohilohi), ʻoluʻolu o ka ʻili, a hiki ke hoʻohaʻahaʻa i kona ʻano mechanical a me nā mea pale.

2. Die Drool / Die Build-up: E pili ana kēia i ka hōʻiliʻili ʻana o nā huahana polymer degradation, haʻahaʻa molecular weight fractions, poorly dispersed additives (eg, pigments, antistatic agents, slip agents), a i ʻole gels mai ka resin ma nā kihi lehelehe make a i ʻole i loko o ka lua make. Hiki i kēia mau waihona ke hoʻokaʻawale i ka wā o ka hana ʻana, e hoʻohaumia i ka ʻili kiʻiʻoniʻoni a hana i nā hemahema e like me nā gels, streaks, a i ʻole nā ​​ʻōpala, a laila e hoʻopilikia i ke ʻano o ka huahana a me ka maikaʻi. I nā hihia koʻikoʻi, hiki i ka make build-up ke ālai i ka puka make, e alakaʻi ana i ke ana ʻana i nā ʻano like ʻole, ka haehae ʻana i ke kiʻiʻoniʻoni, a me ka hoʻoikaika ʻana i ka pani ʻana o ka laina hana no ka hoʻomaʻemaʻe make, e hopena i nā poho nui o ka hana pono a me ka pau ʻana o ka waiwai.

3. Kiʻekiʻe Extrusion Pressure a me Fluctuation: Ma lalo o kekahi mau kūlana, ʻoi aku ka nui o ka hana ʻana i nā resins viscosity kiʻekiʻe a i ʻole ka hoʻohana ʻana i nā āpau make liʻiliʻi, hiki ke kiʻekiʻe ke kaomi i loko o ka ʻōnaehana extruder (ʻoi loa ma ke poʻo extruder a make). ʻAʻole hoʻonui wale ke kaomi kiʻekiʻe i ka hoʻohana ʻana i ka ikehu akā hiki ke pilikia i ka lōʻihi o ke ola ʻana o nā mea hana (e laʻa, ka wili, barela, make) a me ka palekana. Eia kekahi, ʻo nā loli paʻa ʻole o ke kaomi extrusion ke kumu i nā ʻano like ʻole o ka hoʻoheheʻe ʻana, e alakaʻi ana i ka mānoanoa kiʻiʻoniʻoni like ʻole.

4. Ka palena palena ʻia: No ka pale ʻana a i ʻole ka hoʻēmi ʻana i nā pilikia e like me ka haʻihaʻi heheʻe a me ke kūkulu ʻana i ka make, koi pinepine ʻia nā mea hana e hoʻemi i ka wikiwiki o ka extruder screw, a laila e kaupalena ʻia ka puka o ka laina hana. Hoʻopili pololei kēia i ka pono hana a me ke kumukūʻai hana i kēlā me kēia ʻāpana o ka huahana, e paʻakikī ana e hoʻokō i nā koi mākeke no nā kiʻiʻoniʻoni nui a haʻahaʻa.

5. Paʻakikī i ke ana ʻana: Hiki ke hoʻololi ʻia ka mānoanoa o ke kiʻiʻoniʻoni, ma ka ʻaoʻao ʻaoʻao o ka make, ka puʻunaue like ʻole o ka mahana ma waena o ka make. Hoʻopilikia kēia i ka hana ʻana o ke kiʻiʻoniʻoni a me nā hiʻohiʻona hoʻohana hope.

6. Hoʻololi ʻo Resin Paʻakikī: I ka wā e hoʻololi ai ma waena o nā ʻano like ʻole a i ʻole nā ​​​​papa o nā resins polyolefin, a i ka wā e hoʻololi ai i nā masterbatches kala, paʻakikī pinepine nā mea koena o ka holo mua e hoʻomaʻemaʻe loa mai ka extruder a make. ʻO kēia ke alakaʻi i ka hui pū ʻana o nā mea kahiko a me nā mea hou, e hana ana i nā mea hoʻololi, hoʻolōʻihi i nā manawa hoʻololi, a me ka hoʻonui ʻana i nā uku.

ʻO kēia mau pilikia hana maʻamau e kāohi i ka hoʻoikaika ʻana o nā mea hana kiʻiʻoniʻoni polyolefin e hoʻomaikaʻi i ka maikaʻi o ka huahana a me ka hana pono ʻana, a ke kau nei hoʻi i nā mea pale i ka hoʻopaʻa ʻana i nā mea hou a me nā ʻenehana hana holomua. No laila, ʻo ka ʻimi ʻana i nā hopena kūpono e lanakila ai i kēia mau pilikia he mea koʻikoʻi ia no ka hoʻomohala mau a me ke olakino o ka ʻoihana extrusion film polyolefin holoʻokoʻa.

Nā mea hoʻonā no ka Polyolefin Film Extrusion Process: Polymer Processing Aids (PPAs)

ʻO ka Polymer Processing Aids (PPAs) nā mea hoʻohui hana nona ka waiwai nui i ka hoʻomaikaʻi ʻana i ka ʻano rheological o ka polymer melts i ka wā o ka extrusion a me ka hoʻololi ʻana i kā lākou launa pū ʻana me nā papa hana, no laila e lanakila ai i nā pilikia o ka hoʻoponopono ʻana a me ka hoʻomaikaʻi ʻana i ka hana pono a me ka maikaʻi o ka huahana.

1. Nā PPA e pili ana i ka Fluoropolymer

Ke Kinohi a me nā ʻano: ʻO kēia ka papa i hoʻohana nui ʻia, ʻenehana makua, a me ka maikaʻi o ka papa PPA. He mau homopolymers a copolymers ma muli o nā monomers fluoroolefin e like me ka vinylidene fluoride (VDF), hexafluoropropylene (HFP), a me tetrafluoroethylene (TFE), me nā fluoroelastomers ka mea nui loa. ʻO nā kaulahao molekala o kēia mau PPA he waiwai nui i nā mea paʻa kiʻekiʻe-bond-energy, low-polarity CF bonds, e hāʻawi ana i nā waiwai physicochemical kū hoʻokahi: haʻahaʻa haʻahaʻa haʻahaʻa (e like me polytetrafluoroethylene/Teflon®), maikaʻi ka thermal stability, a me ka inertness kemika. ʻO ka mea koʻikoʻi, hōʻike pinepine nā PPA fluoropolymer i ka hoʻohālikelike maikaʻi ʻole me nā matrices polyolefin non-polar (e like me PE, PP). ʻO kēia incompatibility kahi kumu nui no ko lākou neʻe ʻana i nā ʻili metala o ka make, kahi i hana ai lākou i kahi uhi lubricating ikaika.

Nā Huahana Lunamaka'āinana: ʻO nā māka alakaʻi i ka mākeke honua no nā PPA fluoropolymer me Chemours 'Viton™ FreeFlow™ series a me 3M's Dynamar™ series, e kauoha ana i ka māhele mākeke nui. Hoʻohui ʻia, hoʻohana ʻia kekahi mau māka fluoropolymer mai Arkema (Kynar® series) a me Solvay (Tecnoflon®) ma ke ʻano, a i ʻole he mau mea koʻikoʻi i loko o nā hoʻokumu PPA.

2. ʻO nā mea kōkua hoʻoponopono ma muli o ka Silicone-based Processing Aids (PPAs)

ʻO ke kinona a me nā hiʻohiʻona: ʻO nā mea hana mua i kēia papa o nā PPA he polysiloxanes, i kapa ʻia he silicones. ʻO ka iwi kuamoʻo polysiloxane he mau silikoni a me nā ʻātoma oxygen (-Si-O-), me nā pūʻulu organik (maʻamau methyl) i hoʻopili ʻia i nā ʻātoma silicon. Hāʻawi kēia ʻano molekula kūʻokoʻa i nā mea silicone me ka haʻahaʻa haʻahaʻa haʻahaʻa, ke kūpaʻa wela maikaʻi, ka maʻalahi maikaʻi, a me nā waiwai non-adhesive i nā mea he nui. E like me ka fluoropolymer PPAs, silicone-based PPAs hana ma ka neʻe ʻana i nā ʻili metala o nā mea hana e hana ai i kahi papa lubricating.

Nā hiʻohiʻona noi: ʻOiai ʻo ka fluoropolymer PPA e hoʻomalu i ka polyolefin film extrusion sector, silicone-based PPAs e hōʻike i nā pono kūʻokoʻa a i ʻole e hana i nā hopena synergistic ke hoʻohana ʻia i nā hiʻohiʻona noi kikoʻī a i hui pū me nā ʻōnaehana resin. No ka laʻana, hiki ke noʻonoʻo ʻia no nā noi e koi ana i nā coefficient haʻahaʻa haʻahaʻa o ka friction a i ʻole kahi i makemake ʻia nā hiʻohiʻona kikoʻī no ka huahana hope.

Ke alo nei i ka Fluoropolymer Bans a i ʻole ka hoʻolako ʻana i nā pilikia PTFE?

E hoʻoholo i nā pilikia hoʻopiʻi kiʻiʻoniʻoni Polyolefin me ka PFAS-Free PPA Solutions-ʻO ka Fluorine Free Polymer additives a SILIKE

Lawe ʻo SILIKE i kahi ʻano hana me kāna mau huahana SILIMER series, e hāʻawi ana i nā mea houPFAS-free polymer processing aids (PPAs). Hōʻike kēia laina huahana piha i ka 100% pure PFAS-free PPA,nā mea hoʻohui PPA Polymer ʻole fluorine, aPFAS-free & fluorine-free PPA masterbatches.Nahoʻopau i ka pono o nā mea hoʻohui fluorine, ʻO kēia mau mea kōkua kaʻina hana e hoʻonui nui i ke kaʻina hana no LLDPE, LDPE, HDPE, mLLDPE, PP, a me nā kaʻina hana extrusion kiʻiʻoniʻoni polyolefin. Hoʻopili lākou me nā hoʻoponopono kaiapuni hou aʻe e hoʻonui ana i ka pono hana, e hōʻemi ana i ka downtime, a me ka hoʻomaikaʻi ʻana i ka maikaʻi o ka huahana holoʻokoʻa. Hāʻawi ka SILIKE's PFAS-free PPA i nā pōmaikaʻi i ka huahana hope loa, me ka hoʻopau ʻana i ka melt fracture (sharkskin), hoʻomaikaʻi ʻia ka maʻalahi, a me ka maikaʻi o ka ʻili.

Inā ʻoe e hakakā nei me ka hopena o ka pāpā fluoropolymer a i ʻole ka nele o ka PTFE i kāu kaʻina extrusion polymer, hāʻawi ʻo SILIKE.nā mea ʻē aʻe i ka fluoropolymer PPAs/PTFE, Nā mea hoʻohui ʻole PFAS no ka hana kiʻiʻoniʻonii hoʻopili ʻia e hoʻokō i kāu mau pono, me ka hoʻololi ʻole o ke kaʻina hana.