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Gabatarwa zuwa Polyolefins da Fitar Fim

Polyolefins, nau'in kayan macromolecular da aka haɗa daga olefin monomers kamar ethylene da propylene, sune robobi da aka fi samarwa da amfani da su a duniya. Yaɗuwar su ya samo asali ne daga keɓaɓɓen haɗin kaddarorin, gami da ƙarancin farashi, kyakkyawan tsari, ingantaccen kwanciyar hankali, da halaye na zahiri. Daga cikin aikace-aikacen daban-daban na polyolefins, samfuran fim suna riƙe matsayi mai mahimmanci, suna ba da ayyuka masu mahimmanci a cikin kayan abinci, suturar noma, marufi na masana'antu, samfuran kiwon lafiya da tsabta, da kayan masarufi na yau da kullun. Mafi yawan polyolefin resins da aka yi amfani da su don samar da fina-finai sun hada da polyethylene (PE) - wanda ya ƙunshi Linear Low-Density Polyethylene (LLDPE), Low-Density Polyethylene (LDPE), da High-Density Polyethylene (HDPE) - da polypropylene (PP).

Kera fina-finai na polyolefin da farko ya dogara da fasahar extrusion, tare da Blown Film Extrusion da Cast Film Extrusion kasancewa manyan matakai guda biyu.

1. Blown Fim Fitar Tsari

Fitar da fim ɗin busa shine ɗayan hanyoyin da aka fi sani don samar da fina-finan polyolefin. Mahimmin ƙa'idar ta ƙunshi fitar da narkakkar polymer zuwa sama ta hanyar mutuwa ta shekara-shekara, ta samar da parison tubular siriri. Bayan haka, ana shigar da iskar da ke danne a cikin cikin wannan parison, wanda hakan ya sa ta taso cikin kumfa mai diamita mai girma fiye da na mutu. Yayin da kumfa ke hawa, ana sanya shi da karfi da ƙarfi ta hanyar zoben iska na waje. Kumfa mai sanyaya sai a ruguje shi da saitin rollers na nip (sau da yawa ta hanyar firam mai rugujewa ko A-frame) sannan a zana shi ta hanyar abin nadi kafin a raunata a kan nadi. Tsarin fim ɗin da aka busa yawanci yana samar da fina-finai tare da daidaitawar biaxial, ma'ana suna nuna ma'auni mai kyau na kayan aikin injiniya a cikin injin injin (MD) da kuma madaidaiciyar hanya (TD), kamar ƙarfin juriya, juriya, da ƙarfin tasiri. Za a iya sarrafa kauri na fim da kaddarorin inji ta hanyar daidaita ma'aunin busawa (BUR - Rabo na diamita na kumfa don mutu diamita) da ma'aunin zana-saukar (DDR - rabon saurin ɗaukar sama zuwa saurin extrusion).

2. Tsarin Fitar Fina-Finan Fim

Fitar da fim ɗin wani muhimmin tsari ne na samarwa don fina-finai na polyolefin, musamman dacewa don masana'antar fina-finai waɗanda ke buƙatar ingantattun kaddarorin gani (misali, babban haske, babban sheki) da ingantacciyar kauri iri ɗaya. A cikin wannan tsari, ana fitar da narkakkar polymer ɗin a kwance ta hanyar lebur, nau'in T-die mai ramin ramuka, yana samar da narkakken gidan yanar gizo. Ana zana wannan gidan yanar gizon da sauri zuwa saman saman juzu'i ɗaya ko fiye da sanyi mai sanyi a ciki. Narke yana daɗa ƙarfi da sauri akan tuntuɓar saman nadi mai sanyi. Fina-finan ɗimbin yawa gabaɗaya suna da kyawawan kaddarorin gani, taushin yanayi, da kyakkyawan yanayin rufe zafi. Madaidaicin iko akan ratar leɓen mutu, sanyin juyi, da saurin juyawa yana ba da damar ingantaccen tsari na kaurin fim da ingancin saman.

Manyan Kalubalen Fitar Fina-Finan Polyolefin guda 6

Duk da balaga da fasahar extrusion, masana'antun akai-akai suna fuskantar matsaloli na sarrafawa a aikace na samar da fina-finai na polyolefin, musamman lokacin da suke ƙoƙarin samun fitarwa mai girma, inganci, ma'auni mafi ƙarancin ƙarfi, da lokacin amfani da sabbin resins masu girma. Waɗannan batutuwa ba kawai suna shafar kwanciyar hankali na samarwa ba har ma suna tasiri kai tsaye ingancin samfurin ƙarshe da farashi. Mahimman ƙalubalen sun haɗa da:

1. Melt Fracture (Sharkskin): Wannan yana daya daga cikin mafi yawan lahani a cikin extrusion fim din polyolefin. A macroscopically, yana bayyana a matsayin ripples na lokaci-lokaci ko wani wuri mara kyau akan fim ɗin, ko kuma a lokuta masu tsanani, ƙara bayyana murdiya. Karyewar narkewa da farko yana faruwa ne lokacin da adadin juzu'in narkar da polymer ke fita daga mutuwa ya zarce ƙima mai mahimmanci, wanda ke haifar da jujjuyawar igiya tsakanin bangon mutun da narke mai girma, ko lokacin da tsawaitawa a wurin mutuwa ya zarce ƙarfin narkewa. Wannan lahani yana yin tasiri sosai ga kayan gani na fim (tsaranci, mai sheki), santsin saman, kuma yana iya ƙasƙantar da kayan aikin injinsa da shingen shinge.

2. Die Drool / Die Gina-up: Wannan yana nufin a hankali tarawa na polymer lalata kayayyakin, low kwayoyin nauyi juzu'i, talauci tarwatsa Additives (misali, pigments, antistatic jamiái, zamewa jamiái), ko gels daga guduro a mutu lebe gefuna ko a cikin mutu kogon. Wadannan adibas na iya raguwa a lokacin samarwa, gurɓata fuskar fim da haifar da lahani kamar gels, streaks, ko scratches, ta haka yana shafar bayyanar samfurin da inganci. A cikin lokuta masu tsanani, haɓakawar mutuƙar na iya toshe fitar da mutu, wanda ke haifar da bambance-bambancen ma'auni, yage fim, kuma a ƙarshe tilasta rufe layin samarwa don tsaftacewar mutu, yana haifar da hasara mai yawa a cikin ingantaccen samarwa da ɓarnatar albarkatun ƙasa.

3. Babban matsin lamba da canzawa: A karkashin wasu halaye, musamman lokacin aiwatar da gonsin mai girma ko amfani da karami a cikin tsarin da ya mutu (musamman a kan hanyar wuta) na iya zama mai wuce gona da iri. Babban matsin lamba ba kawai yana ƙara yawan kuzari ba har ma yana haifar da haɗari ga tsawon kayan aiki (misali, dunƙule, ganga, mutu) da aminci. Bugu da ƙari kuma, rashin daidaituwa a cikin matsa lamba na extrusion kai tsaye yana haifar da bambance-bambance a cikin fitarwa na narkewa, wanda ke haifar da kauri na fim mara kyau.

4. Ƙimar Ƙarfin Ƙarfi: Don hana ko rage al'amurran da suka shafi kamar narke karaya da kuma mutuwa ginawa, masana'antun sau da yawa ana tilasta su rage gudun dunƙule extruder, game da shi iyakance samar line ta fitarwa. Wannan kai tsaye yana tasiri ingancin samarwa da farashin masana'anta a kowace naúrar samfur, yana mai da wahala a iya biyan buƙatun kasuwa na manyan sikelin, fina-finai masu rahusa.

5. Wahala a Ma'auni Control: Rashin zaman lafiya a cikin narke kwarara, ba Uniform zazzabi rarraba fadin mutuwa, da kuma mutu gina-up iya duk iya ba da gudummawa ga bambance-bambance a cikin fim kauri, duka transversely da longitudinally. Wannan yana rinjayar aikin sarrafa fim na gaba da halayen amfani na ƙarshe.

6. Wuyawar Resin Canjin: Lokacin canzawa tsakanin nau'ikan daban-daban ko maki na resins na polyolefin, ko kuma lokacin canza manyan nau'ikan launi, sauran kayan da suka rage daga gudu na baya galibi yana da wahala a share gaba ɗaya daga mai fitar da su kuma su mutu. Wannan yana haifar da haɗuwa da tsofaffi da sababbin kayan, samar da kayan canja wuri, tsawaita lokutan canji, da ƙara yawan tarkace.

Waɗannan ƙalubalen sarrafawa na gama gari suna ƙuntata ƙoƙarin masana'antun fina-finai na polyolefin don haɓaka ingancin samfura da ingancin samarwa, kuma suna haifar da shinge ga ɗaukar sabbin kayan aiki da dabarun sarrafa ci gaba. Don haka, neman ingantattun mafita don shawo kan waɗannan ƙalubalen yana da mahimmanci ga ci gaba mai dorewa da lafiya na duk masana'antar extrusion fim ɗin polyolefin.

Magani don Tsarin Fitar da Fina-Finan Polyolefin: Abubuwan Taimako na Processing Polymer (PPAs)

Polymer Processing Aids (PPAs) additives ne na aiki waɗanda ainihin ƙimar su ta ta'allaka ne da haɓaka halayen rheological na polymer narke yayin extrusion da canza hulɗar su tare da saman kayan aiki, ta haka ne ke shawo kan kewayon matsalolin sarrafawa da haɓaka haɓaka samarwa da ingancin samfur.

1. PPAs na tushen Fluoropolymer

Siffar Sinadarai da Halaye: Waɗannan a halin yanzu an fi amfani da su, balagagge na fasaha, da kuma nuna tasiri na PPAs. Suna yawanci homopolymers ko copolymers bisa ga monomers fluoroolefin kamar su vinylidene fluoride (VDF), hexafluoropropylene (HFP), da tetrafluoroethylene (TFE), tare da fluoroelastomers sune mafi wakilci. Sarƙoƙin ƙwayoyin cuta na waɗannan PPAs suna da wadata a cikin ƙarfin haɗin gwiwa, ƙarancin ƙarfi na CF shaidu, waɗanda ke ba da kaddarorin physicochemical na musamman: ƙarancin ƙarfi mai ƙarancin ƙarfi (kamar polytetrafluoroethylene/Teflon®), kyakkyawan kwanciyar hankali na thermal, da rashin kuzarin sinadarai. Mahimmanci, PPAs na fluoropolymer gabaɗaya suna nuna rashin daidaituwa tare da matrices polyolefin mara iyaka (kamar PE, PP). Wannan rashin daidaituwa shine babban abin da ake buƙata don ƙaura mai inganci zuwa saman ƙarfe na mutu, inda suke samar da murfin mai mai ƙarfi.

Samfuran Wakilai: Manyan samfuran a kasuwannin duniya don PPAs na fluoropolymer sun haɗa da Chemours' Viton ™ FreeFlow ™ jerin da jerin Dynamar 3M na 3M, waɗanda ke ba da umarnin babban rabon kasuwa. Bugu da ƙari, wasu makin fluoropolymer daga Arkema (Jerin Kynar®) da Solvay (Tecnoflon®) ana kuma amfani da su azaman, ko mahimman abubuwan haɗin gwiwa a cikin, ƙirar PPA.

2. Silicone-based Processing Aids (PPAs)

Tsarin Kemikal da Halaye: Babban abubuwan da ke aiki a cikin wannan aji na PPA sune polysiloxanes, waɗanda aka fi sani da silicones. Kashin baya na polysiloxane ya ƙunshi musanya siliki da atom ɗin oxygen (-Si-O-), tare da ƙungiyoyin kwayoyin halitta (yawanci methyl) waɗanda ke haɗe da ƙwayoyin silicon. Wannan tsari na musamman na kwayoyin halitta yana ba da kayan silicone tare da ƙananan tashin hankali, kyakkyawan kwanciyar hankali na thermal, sassauci mai kyau, da kaddarorin marasa mannewa ga abubuwa da yawa. Mai kama da Fluoropolymer PPAs, PPAs na tushen silicone yana aiki ta hanyar ƙaura zuwa saman saman ƙarfe na kayan aiki don samar da Layer mai mai.

Siffofin aikace-aikacen: Kodayake PPAs na fluoropolymer sun mamaye sashin extrusion na fim na polyolefin, PPAs na tushen silicone na iya nuna fa'idodi na musamman ko ƙirƙirar tasirin daidaitawa lokacin amfani da takamaiman yanayin aikace-aikacen ko tare da tsarin resin musamman. Misali, ana iya la'akari da su don aikace-aikacen da ke buƙatar ƙarancin ƙididdiga na juzu'i ko kuma inda ake son takamaiman halaye na samfurin ƙarshe.

Ana fuskantar Bans na Fluoropolymer ko Kalubalen Samar da PTFE?

Warware Kalubalen Fitar Fim na Polyolefin tare da Maganin PPA-Free na PFAS-SILIKE's Fluorine Free Polymer Additives

SILIKE yana ɗaukar hanya mai fa'ida tare da samfuran samfuran sa na SILIMER, yana ba da sabbin abubuwaKayan aikin sarrafa polymer kyauta na PFAS (PPAs). Wannan ingantaccen layin samfurin yana fasalta 100% tsarkakakken PFAS-free PPAs,Abubuwan ƙari na PPA Polymer marasa fluorine, kumaPFAS-kyauta & PPA masterbatches marasa fluorine.Takawar da buƙatar abubuwan da ake amfani da su na fluorine, Wadannan kayan aiki na kayan aiki suna haɓaka tsarin masana'antu don LLDPE, LDPE, HDPE, mLLDPE, PP, da kuma matakai daban-daban na polyolefin. Suna daidaitawa tare da sabbin ƙa'idodin muhalli yayin da suke haɓaka haɓakar samarwa, rage raguwar lokaci, da haɓaka ingancin samfur gabaɗaya. SILIKE's PFAS-free PPAs yana kawo fa'idodi ga samfurin ƙarshe, gami da kawar da karyewar narkewa (sharkskin), ingantaccen santsi, da ingantaccen ingancin saman.

Idan kuna kokawa da tasirin bans na fluoropolymer ko ƙarancin PTFE a cikin ayyukan extrusion ɗin ku na polymer, SILIKE yana bayarwa.madadin zuwa fluoropolymer PPAs/PTFE, Abubuwan da ba su da PFAS don masana'antar fimwaɗanda aka keɓance don biyan bukatunku, ba tare da canjin tsari da ake buƙata ba.