High-density polyethylene (HDPE) yog crystalline thermoplastic resin polymerized los ntawm ethylene monomers nyob rau hauv kev sib koom tes los yog Ziegler-Natta catalysis. Nws cov yam ntxwv tshwj xeeb yog tsim los ntawm nws cov qauv tsim qauv zoo heev thiab cov crystallinity siab, uas tso cai rau cov khoom siv nrog cov khoom muaj txiaj ntsig zoo hauv cov khoom siv kho tshuab, kev tiv thaiv ib puag ncig, thiab kev ua kom haum, ua rau nws cov ntawv thov dav hauv ntau lub teb chaws thiab pej xeem.
Los ntawm cov qauv molecular foundations, HDPE lub ntsiab saw yog feem ntau linearly teem, nrog ob peb thiab luv ceg. Cov saw hlau molecular tau yooj yim ntim ua ke los tsim cov cheeb tsam crystalline, nrog cov crystallinity feem ntau tshaj 80%. This structural feature directly results in its high density (0.941–0.965 g/cm³), significantly higher than low-density polyethylene (LDPE). High crystallinity tsis tsuas yog txhim kho cov khoom rigidity, hardness, thiab tensile lub zog (feem ntau 20-35 MPa), tab sis kuj txhim khu creep kuj, tso cai rau cov khoom kom tswj cov duab thiab seem stability nyob rau hauv ntev - lub sij hawm load tej yam kev mob.
Nyob rau hauv cov nqe lus ntawm txhua yam khoom, HDPE ua ke zoo toughness thiab cuam tshuam tsis kam, tuav lub zog muaj zog txawm nyob rau hauv qis kub. Nws qhov kev cuam tshuam lub zog qhia tau hais tias qhov hloov pauv me me nrog qhov kub thiab txias, ua kom pom kev ua haujlwm zoo rau kev tawg tawg. Nws cov ntsiab lus melting yog kwv yees li 120-130 degree, thiab nws cov Vicat softening point yog siab dua 110 degree, tso cai rau nws tswj cov txheej txheem kev ncaj ncees thiab txhim khu kev qha kev ua tau zoo tshaj qhov kub ntau, ua rau nws haum rau siab - bearing, heat-resistant, thiab ntev - siv sab nraum zoov.
Cov tshuaj tiv thaiv corrosion yog lwm yam tseem ceeb ntawm HDPE. Nws cov saw hlau molecular muaj cov qauv saturated hydrocarbon, nthuav tawm qhov ua haujlwm zoo rau feem ntau cov kua qaub, alkalis, ntsev tov, thiab polar organic solvents. Nws yog insoluble nyob rau hauv cov kuab tshuaj uas tsis yog dej thiab aliphatic hydrocarbons nyob rau hauv chav tsev kub, ua kom pom kev ruaj khov muaj peev xwm nyob rau hauv chemical ntim, pipelines, thiab corrosion-cov khoom tiv thaiv. Tib lub sijhawm, HDPE muaj cov khoom siv hluav taws xob zoo thiab tsis muaj dielectric poob, ua rau nws tsim nyog rau cov hluav taws xob sheathing thiab rwb thaiv tsev.
Nyob rau hauv cov nqe lus ntawm kev ua tau zoo, HDPE yaj viscosity yog nruab nrab thiab nws flowability yog zoo, ua rau nws haum rau ntau yam molding txheej txheem xws li tshuab molding, extrusion, txhaj molding, thiab rotational molding. Tshuab moulding ua tau zoo rau kev tsim cov khoom hollow xws li lub raj mis, cov kaus poom, thiab cov thoob; extrusion yog tsim rau kev tsim khoom txuas ntxiv ntawm cov kav dej, cov ntawv, thiab cov profiles, tshwj xeeb tshaj yog rau cov kav dej hauv nroog thiab cov kav dej thiab cov kav dej xa hluav taws xob; Kev txhaj tshuaj molding tuaj yeem tsim cov khoom nrog cov duab nyuaj thiab qhov tseeb qhov tseeb, xws li cov thawv ntim khoom, pallets, thiab cov khoom lag luam; rotational molding tuaj yeem ua rau pwm loj seamless cia tso tsheb hlau luam thiab ntim khoom, nrog rau kev ua haujlwm zoo rau ib puag ncig kev ntxhov siab tawg.
Hais txog kev hloov pauv ib puag ncig, HDPE tuaj yeem ua ke nrog cov tshuaj tua kab mob antioxidant thiab lub teeb stabilizers txhawm rau txhim kho huab cua tsis kam, tswj kev ua haujlwm ruaj khov txawm tias tom qab siv sijhawm ntev - sab nraum zoov. Nws cov khoom yog recyclable thiab reusable; los ntawm lub cev rov tsim dua tshiab lossis tshuaj depolymerization thiab repolymerization, cov peev txheej rov ua dua tshiab tuaj yeem ua tiav, ua tau raws li qhov yuav tsum tau muaj ntawm kev txhim kho kom ruaj khov.
Hauv cov ntsiab lus, HDPE, nrog nws cov qauv tsis tu ncua, crystallinity siab, thiab cov khoom zoo tshaj plaws, tsim cov yam ntxwv tshwj xeeb. Nws muaj cov txiaj ntsig tseem ceeb hauv lub zog, tiv thaiv corrosion, tiv thaiv tshav kub, thiab kev ua haujlwm ntau yam, ua rau nws yog ib tus neeg sawv cev tseem ceeb ntawm cov ntaub ntawv polymer niaj hnub uas ua ke nrog kev ntseeg siab thiab kev lag luam. Nws cov yam ntxwv ua haujlwm muab lub hauv paus ruaj khov rau kev txhim kho thiab siv ntau yam khoom siv siab -kev ua tau zoo.
