Rarraba ilimin kayan polymer

1. Nau'in tsufa na kayan polymer

Abubuwan polymer a cikin tsari na sarrafawa, ajiya da amfani, saboda cikakken aikin abubuwan ciki da na waje, kaddarorinsa suna raguwa a hankali, don haka asarar ƙimar amfani ta ƙarshe, wannan sabon abu yana da tsufa na kayan polymer.

Wannan ba wai kawai yana haifar da almubazzaranci ba, har ma yana haifar da manyan hatsarori saboda gazawar aikin sa, kuma rugujewar kayan da tsufansa ke haifarwa na iya gurbata muhalli.

Saboda nau'in polymer daban-daban da yanayin amfani daban-daban, akwai abubuwan tsufa da halaye daban-daban.Gabaɗaya, ana iya rarraba tsufa na kayan polymer zuwa nau'ikan canje-canje huɗu masu zuwa:

Canje-canje a cikin bayyanar

Akwai tabo, tarkace, layin azurfa, fasa, sanyi, foda, gashi, warping, fisheye, wrinkling, shrinkage, ƙonawa, murɗawar gani da canje-canje a launi na gani.

Canje-canje a cikin kaddarorin jiki

Ciki har da solubility, kumburi, rheological Properties da sanyi juriya, zafi juriya, ruwa permeability, iska permeability da sauran kaddarorin canji.

Canje-canje a cikin kayan aikin injiniya

Ƙarfin ƙarfi, ƙarfin lanƙwasa, ƙarfin ƙarfi, ƙarfin tasiri, haɓaka dangi, shakatawa na damuwa, da dai sauransu.

Canje-canje a cikin kayan lantarki

Irin su juriya na ƙasa, juriya ƙara, dielectric akai-akai, ƙarfin rushewar wutar lantarki.

2. Abubuwan da ke haifar da tsufa na kayan polymer

Domin a cikin sarrafa polymer, tsarin amfani, zai shafi zafi, oxygen, ruwa, haske, microorganism da abubuwan muhalli kamar matsakaicin sinadarai hade da sinadaran da tsarinsa na iya haifar da jerin canje-canje, daidaitattun kaddarorin jiki, irin su. kamar yadda gashi mai tauri, karyewa, mai danko, canza launi, rashin ƙarfi da sauransu, waɗannan canje-canjen da al'amuran ana kiransu tsufa.

Babban polymer a ƙarƙashin aikin zafi ko haske zai samar da kwayoyin halitta masu farin ciki, lokacin da makamashi ya isa sosai, sarkar kwayar halitta za ta karya don samar da radicals kyauta, free radicals na iya haifar da wani nau'i na sarkar a cikin polymer, ci gaba da haifar da lalacewa, kuma zai iya haifar da lalacewa. haɗe-haɗe.

Idan oxygen ko ozone ya kasance a cikin yanayi, za a iya haifar da jerin halayen oxygenation don samar da hydroperoxides (ROOH), wanda za'a iya kara lalacewa zuwa ƙungiyoyin carbonyl.

Idan akwai ragowar ion ƙarfe masu haɓakawa a cikin polymer, ko ions ƙarfe kamar jan ƙarfe, ƙarfe, manganese da cobalt ana shigar da su cikin polymer yayin aiki da amfani, za a ƙara haɓaka halayen lalatawar oxidation na polymer.

3. Hanyoyin rigakafin tsufa na kayan polymer

A halin yanzu, manyan hanyoyin haɓakawa da haɓaka abubuwan rigakafin tsufa na kayan polymer sune kamar haka:

Tsufa na kayan polymer, musamman tsufa na photooxygen, na farko yana farawa daga saman kayan ko samfurin, wanda aka bayyana a matsayin discoloration, foda, fatattaka, raguwa mai sheki, sannan a hankali zuwa ciki.

Kayayyakin bakin ciki suna da yuwuwar gazawa a baya fiye da samfuran kauri, don haka rayuwar sabis na samfuran za'a iya tsawaita samfuran ta hanyar kauri.

Don sauƙi ga samfuran tsufa, ana iya shafa su a saman ko kuma a rufe shi da wani nau'in murfin juriya mai kyau, ko kuma a cikin ɓangaren waje na samfurin haɗe-haɗe na kayan juriya mai kyau, ta yadda fuskar samfurin a haɗe zuwa Layer. na Layer na kariya, don jinkirta tsarin tsufa.

A cikin tsarin hadawa ko shirye-shirye, yawancin kayan kuma suna da matsalar tsufa.Alal misali, sakamakon zafi a cikin tsarin polymerization, thermal oxygen tsufa a cikin tsarin aiki da sauransu.Dangane da haka, ana iya rage tasirin iskar oxygen ta ƙara na'urorin deoxygenation ko na'urori masu ɓoyewa a cikin polymerization ko tsarin sarrafawa.

Koyaya, wannan hanyar zata iya ba da garantin aikin kayan aiki ne kawai a cikin masana'anta, kuma ana iya aiwatar da wannan hanyar ne kawai daga tushen shirye-shiryen kayan, ba za a iya magance matsalar tsufa ba a cikin tsarin sake sarrafawa da amfani.

Akwai ƙungiyoyi waɗanda suke da sauƙin tsufa a cikin tsarin kwayoyin halitta na kayan aikin polymer da yawa, don haka ta hanyar tsarin tsarin kwayoyin halitta na kayan aiki, maye gurbin ƙungiyoyin da ba su da sauƙin tsufa tare da ƙungiyoyi masu sauƙi na iya sau da yawa suna yin tasiri mai kyau.

Ko kuma gabatar da ƙungiyoyi masu aiki ko tsarin tare da tasirin tsufa akan sarkar kwayoyin halitta ta polymer ta hanyar grafting ko hanyar copolymerization, ba da kayan kanta da kyakkyawan aikin rigakafin tsufa, kuma hanya ce da masu bincike suka saba amfani da su, amma farashin yana da yawa. kuma ba zai iya cimma manyan samarwa da aikace-aikace ba.

A halin yanzu, hanyar da ta dace da kuma hanyar da aka saba amfani da ita don inganta juriya na tsufa na kayan polymer shine don ƙara abubuwan da ake amfani da su na tsufa, wanda aka yi amfani da shi sosai saboda ƙananan farashi kuma babu buƙatar canza tsarin samar da kayan aiki.Akwai manyan hanyoyi guda biyu don ƙara waɗannan additives anti-tsufa:

Direct Bugu da kari na Additives: anti-tsufa Additives (foda ko ruwa) da guduro da sauran albarkatun kasa kai tsaye gauraye da zuga bayan extrusion granulation ko allura gyare-gyare, da dai sauransu Saboda da sauki, wannan hanyar ƙara ne yadu amfani a da yawa famfo da kuma yin amfani da shi. allura gyare-gyare masana'antu.

Hanyar ƙarin tsufa na masterbatch: A cikin masana'antun da ke da buƙatu masu girma don ingancin samfur da kwanciyar hankali, ya fi zama gama gari don ƙara masterbatch na rigakafin tsufa a cikin samarwa.

Anti-tsufa masterbatch dace guduro a matsayin mai ɗauka, gauraye da iri-iri na tasiri anti-tsufa Additives, sa'an nan ta hanyar twin-dunƙule extruder co-extrusion granulation, da aikace-aikace abũbuwan amfãni ta'allaka ne a anti-tsufa Additives a kan aiwatar da shirya masterbatch farko aiwatar. da tarwatsa, don haka marigayi a kan aiwatar da kayan aiki, anti-tsufa wakili samu sakandare watsawa, Don cimma manufar uniform watsawa auxiliaries a cikin polymer abu matrix, ba kawai don tabbatar da ingancin samfurin kwanciyar hankali, amma kuma don kauce wa. gurɓataccen ƙura a lokacin samarwa, yana sa samar da ƙarin kore da kare muhalli.