I-Polyacrylonitrile (PAN) ikhampasi esetshenzisiwe yekhabhoni izwakala ilula ngekhwalithi, incane endaweni ethile yokushisa, ithambile ngokuthungwa, inobuhle obusezingeni eliphezulu futhi ilula ekusebenzeni, okungonga amandla amakhulu. Ngakho-ke, ukufakwa okushisayo kwesisekelo se-polyacrylonitrile kuphakame kakhulu endaweni ye-vacuum noma ye-inert, ikakhulukazi, ukusebenza kwesisekelo se-polyacrylonitrile kuzinzile ngaphansi kwezimo zokushisa eziphakeme, futhi kungumbhalo omuhle kakhulu wokufakelwa kwe-Vacuum Furnace.