Polyethylene Terephthalate (Pet) ndi ma crystalline polimmer okhala ndi kukana bwino mankhwala, sungunulani kuyenda komanso kusiyanitsa. Polymer amapangidwa ndi mayunitsi obwereza monga momwe chithunzi 1. Chigawo chilichonse chokhala ndi kutalika kwa 1.09 nm ndi kulemera kwa ~ 200. Ikapangidwa kuchokera ku terephthalic acid ndi ethylene glycol, imagunda kumanzere kwa H- ndi Ufulu wa -O. Polymerization imatero ndikupanga madzi omwe amachotsedwa pansi pa kutentha kwa kutentha ndi vacuum. Momwemonso kukhalapo kwa madzi mu boma losungunula lidzagwetsa mofulumira kapangidwe kake kuti kuyanika kwa polymer musanasungunuke ndi ulusi.

Mphete yowoneka bwino yophatikizidwa ndi chingwe chofupika chimapangitsa polymer molekyulu yolimba poyerekeza ndi ma polymefic ena monga polyyalefin kapena polyalefin. Kuperewera kwa matenda ang'onoang'ono mu maunyolo a polymer kumapangitsa kukhala kukhazikika kwamphamvu kwambiri. Polymer yolemba ndalama idzakhala ndi maofesi a 100 obwereza kotero kuti kutalika kwakutali kwa unyolo wa polymer ndi pafupifupi 100nm ndi zolemetsa zonenepa 20,000. Mitundu yapamwamba ya polymerization imatulutsa mphamvu zapamwamba koma kusungunuka ndikusungunuka komanso kukhazikika kwa kusungunuka mpaka kuchuluka kwa chinyezi kumapangitsa kuwonongeka kwa hydroly. Kukula kwa ma digiri ya polymerization kumachitika ndi mafayilo osungunuka (poyesa kupanikizikawo akuponyera orliction ovomerezeka) kapena mamasukidwe a polymer yosiyanasiyana. Zomaliza ndizofanana ndi kutalika kwa polymer uscket yotchedwa chidwi kapena iv ndi mtengo wa place grade polymer ndi 60/4 w0/40 w / w matrachloroene solvent. IV yolumikizira imakhudzana ndi MV (ma viscence pafupifupi olemera) a polymer polic ndi chizindikiro cha Markenk equan equation (equation 1).