Polycarbonate(PC) ili ndi magulu a carbonate mu unyolo wa maselo. Malinga ndi magulu osiyanasiyana a ester mu kapangidwe ka maselo, amatha kugawidwa m'magulu a aliphatic, alicyclic ndi onunkhira. Pakati pawo, gulu lonunkhira ndilofunika kwambiri. Chofunikira kwambiri ndi bisphenol A polycarbonate, yokhala ndi kulemera kwake kwa molekyulu (MW) ya 200000 mpaka 100000.

Polycarbonate ili ndi zinthu zabwino zonse, monga mphamvu, kulimba, kuwonekera, kukana kutentha ndi kukana kuzizira, kukonza kosavuta komanso kuchedwa kwamoto. Magawo akuluakulu akumunsi ogwiritsira ntchito ndi zida zamagetsi, zitsulo zamapepala ndi magalimoto. Mafakitale atatuwa amatenga pafupifupi 80% yamafuta a polycarbonate. Minda ina imagwiritsidwanso ntchito kwambiri pamakina amakina, ma CD, zonyamula, zida zamaofesi, chithandizo chamankhwala, filimu, zosangalatsa ndi zida zodzitetezera, ndipo akhala amodzi mwamagulu omwe akukula mwachangu apulasitiki asanu a engineering.
Ndi kupita patsogolo kwaukadaulo wakumaloko, kukhazikitsidwa kwamakampani aku China PC kwakula kwambiri m'zaka zaposachedwa. Pofika kumapeto kwa 2022, kukula kwamakampani a PC aku China kudapitilira matani 2.5 miliyoni / chaka, ndipo zotulutsa zake ndi pafupifupi matani 1.4 miliyoni. Pakali pano, mabizinesi akuluakulu aku China akuphatikizapo Kesichuang (matani 600000/chaka), Zhejiang Petrochemical (matani 520000/chaka), Luxi Chemical (matani 300000/chaka) ndi Zhongsha Tianjin (matani 260000/chaka).
Phindu la njira zitatu za PC
Pali njira zitatu zopangira PC: njira yopanda phosgene, njira ya transesterification ndi interfacial polycondensation phosgene process. Pali kusiyana koonekeratu kwa zipangizo ndi ndalama zomwe zimagwiritsidwa ntchito popanga. Njira zitatu zosiyana zimabweretsa mapindu osiyanasiyana a PC.
M'zaka zisanu zapitazi, phindu la PC yaku China linafika pamlingo wapamwamba kwambiri mu 2018, kufika pafupifupi 6500 yuan/ton. Pambuyo pake, mlingo wa phindu unatsika chaka ndi chaka. M'chaka cha 2020 ndi 2021, chifukwa cha kuchepa kwa kuchuluka kwa anthu omwe amamwa mowa chifukwa cha mliriwu, phindu lidachepa kwambiri, ndipo njira ya condensation phosgene ndi njira yopanda phosgene idatayika kwambiri.
Pofika kumapeto kwa 2022, phindu la njira ya transesterification pakupanga PC yaku China ndilapamwamba kwambiri, kufika 2092 yuan/tani, kutsatiridwa ndi njira ya polycondensation phosgene, ndi phindu pa 1592 yuan/tani, pomwe phindu lopanga mwaukadaulo la njira yopanda phosgene. ndi 292 yuan/ton. M'zaka zisanu zapitazi, njira ya transesterification nthawi zonse yakhala yopindulitsa kwambiri pakupanga ma PC aku China, pomwe njira yopanda phosgene imakhala ndi phindu lochepa kwambiri.
Kusanthula kwazinthu zomwe zimakhudza phindu la PC
Choyamba, kusinthasintha kwamtengo wa bisphenol A ndi DMC kumakhudza mwachindunji mtengo wa PC, makamaka kusinthasintha kwa mtengo wa bisphenol A, komwe kumakhala ndi kulemera kwake kuposa 50% pa mtengo wa PC.
Chachiwiri, kusinthasintha kwa msika wa ogula, makamaka kusinthasintha kwachuma, kumakhudza kwambiri msika wa ogula pa PC. Mwachitsanzo, muzaka za 2020 ndi 2021, mliri ukakhudza, kuchuluka kwa msika wa ogula pama PC kwatsika, zomwe zidapangitsa kutsika kwakukulu kwamitengo ya PC ndikukhudzidwa mwachindunji paphindu la msika wa PC.
Mu 2022, zotsatira za mliriwu zidzakhala zowopsa. Mtengo wa mafuta osapsa upitilirabe kutsika, ndipo msika wa ogula udzakhala wosauka. Mankhwala ambiri aku China sanafikire malire a phindu. Pamene mtengo wa bisphenol A umakhalabe wotsika, mtengo wopangira PC ndi wotsika. Kuonjezera apo, kutsika kwatsikirako kwabwereranso kumlingo wakutiwakuti, kotero mitengo yamitundu yosiyanasiyana yopangira ma PC yakhalabe yopindulitsa kwambiri, ndipo phindu likupita patsogolo pang'onopang'ono. Ndi chinthu chosowa chochita bwino kwambiri m'makampani opanga mankhwala aku China. M'tsogolomu, msika wa bisphenol A udzapitirira kukhala waulesi, ndipo Chikondwerero cha Spring chikuyandikira. Ngati kuwongolera mliri kumatulutsidwa mwadongosolo, kufunikira kwa ogula kumatha kukulirakulira, ndipo malo opindulitsa a PC angapitirize kukula.