Qhov txawv ntawm LDPE thiab LLDPE Cov Ntaub Ntawv

Tsawg ntom ntom polyethylene degree polyethylene (LDPE) yog ib cov khoom yas uas tsim rau ntau yam molding kev ua haujlwm ntawm thermoplastic molding thiab muaj moldability zoo. LDPE yog siv rau cov khoom siv yeeb yaj duab, tseem siv tshuaj molding cov khoom, cov khoom kho mob, pharmaceuticals thiab zaub mov ntim khoom, tshuab moulding hollow molding khoom.

Cov kab uas tsis tshua muaj Polyethylene (LLDPE) yog ethylene nrog cov me me dua alpha-olefins (xws li butene-1, hexene-1, octene-1, tetramethylpentene-1, etc.) nyob rau hauv kev kub siab los sis ib lub siab luv polymerized copolymer density ntawm 0.915 rau 0.9 rau qhov tsawg ntom polyethylene daim ntaub ntawv ntawm 40 g / cm3. Lub qauv molecular ntawm cov pa LLDPE yog tus cwj pwm los ntawm nws txoj kab saw loj, nrog me ntsis los yog tsis ntev ceg ntoo, tab sis nrog qee ceg luv. Tsis ntev ntev cov branching, cov crystallinity ntawm lub polymer ntau dua.

Cov khoom siv LLDPE yog cov khoom tsis zoo, cov khoom noj, tsis muaj ntxhiab thiab muaj cov cwj pwm dawb. Sib piv nrog LDPE, nws muaj qhov ua tau zoo ntawm lub zog, lub zog toughness, muaj zog rigidity, kub ua haujlwm, txias ua haujlwm, thiab lwm yam. Nws kuj muaj kev tiv thaiv tsis zoo rau kev puag ncig kev nyuaj siab, rhuav lub zog, thiab tiv taus acids, alkalis, organic solvents, lwm yam zoo li

Ob lub LDPE thiab LLDPE muaj kev nqhis dej zoo los yog yaj tsuab. LLDPE muaj tsawg dua shear nws vim hais tias nws muaj ib qho nqaim nyhav rau lub cev thiab cov ceg ntoo luv luv.

Thaum lub sij hawm shearing (eg, extrusion), LLDPE tswj cov viscosity ntau dua thiab yog vim li ntawd nyuaj rau txheej txheem dua LDPE nrog tib lub cim index. Nyob rau hauv extrusion, qhov txo shear rhiab heev ntawm LLDPE ua rau kev nyuaj siab so ntawm polymer molecular chains sai dua, thiab yog li cov rhiab heev ntawm lub cev khoom rau kev hloov hauv tshuab tawg-nqi.

Hauv kev ncua ntev, LLDPE feem ntau muaj qis viscosity ntawm ntau cov nqi. Qhov no txhais tau hais tias nws yuav tsis tau sib zog ua tawv tawv thaum ncav tes zoo li LDPE. Nrog rau cov nqi ntawm cov ntaub pua plag polyethylene tau nce. LDPE qhia tau hais tias yog ib qho ua rau kev xav ua kom sib haum, uas yog los ntawm daim ntawv thov molecular chain entanglement kom tsis tshua muaj kab mob polyethylene.