I-PolyethYlene Terephthalate (Pet) iyi-semi crystalline polymer enokumelana kahle kwamakhemikhali, ukuncibilika kokuhamba nokuwohloka. I-polymer yakhiwa amayunithi aphindaphindwayo njengoba kukhonjisiwe ku-Sim 1. Iyunithi ngalinye elinobude obungaphezulu kwe-1.09 nm kanye nesisindo se-molecular of ~ 200. Lapho kukhiqizwa kusukela ekuphendukelweni kwe-terephthalic acid kanye ne-ethylene glycol, kufakwe kwesobunxele ngakwesobunxele ngu-h- kwesokudla ngu-loh. I-polymerization ihambisana nokukhiqizwa kwamanzi okususwa ngaphansi kwezinga lokushisa eliphakeme kanye ne-vacuum. Ngakho-ke ubukhona bamanzi ku-molten state buzoshesha ngokushesha lesakhiwo ukuze ukomiswa ngokuphelele kwe-polymer ngaphambi kokuncibilika kwemicu kuyadingeka.

Indandatho ephunyukayo ehambisana ne-aliphatic chain emfushane yenza i-polymer ibe yi-molecule elukhuni ngokuqhathaniswa namanye ama-aliphatic polymers afana ne-polyolefit noma i-polyamide. Ukuntuleka kokuhamba kwesendlali emakhethini we-polymer kuphumela ekuzinweni okuphezulu okushisayo. I-polymer ye-Textile ye-Textermer izoba nenombolo ephakathi yamayunithi aphindaphindwe ngama-molecule nge-molecule ngayinye ukuze ubude be-polymer chain bubalelwa ku-100,000. Higher levels of polymerization produces higher strength fibers but the melt viscosity and stability of the melt to even tiny amounts of moisture causes hydrolytic degradation. Ukulinganiswa kwezilinganiso eziphakathi kwe-polymerization kwenziwa kungaba yi-viscosity ebiwe (ngokulinganisa ukwehla kwengcindezi nge-orifice evuthayo) noma i-viscosity ye-polymer exutshisiwe kwi-solvent efanelekile. Lesi sakamuva sisilinganiso sobude be-polymer chain ezaziwa ngokuthi i-intellingsic viscosity noma i-IV kanye nenani le-fiber grade grade polymer ngu-0.6 dl / g ngo-60/40 inhlanganisela ye-phenol ne-tetrachlorohoethane solvent. I-IV ku-solvent yokugcina ihlobene ne-MV (I-Viscosity Isisindo Molecular isisindo) se-polymer nge-Mark Holimpic Equation (equation 1).