Pipe (rau Irrigation)

High-density polyethylene, lub npe lus Askiv yog "High Density Polyethylene", lossis "HDPE" luv luv.HDPE yog crystalline heev, uas tsis yog-polar thermoplastic cob.Cov tsos ntawm thawj HDPE yog milky dawb, thiab cov seem nyias yog translucent rau qee yam.PE muaj kev tiv thaiv zoo rau feem ntau cov tshuaj hauv tsev thiab kev lag luam.Qee hom tshuaj muaj peev xwm ua rau cov tshuaj corrosion, xws li corrosive oxidants (concentrated nitric acid), aromatic hydrocarbons (xylene) thiab halogenated hydrocarbons (carbon tetrachloride).Lub polymer yog non-hygroscopic thiab muaj dej vapor tsis kam, thiab tuaj yeem siv rau lub hom phiaj ntim.HDPE muaj cov khoom siv hluav taws xob zoo, tshwj xeeb tshaj yog lub zog dielectric siab ntawm rwb thaiv tsev, ua rau nws zoo heev rau cov xov hlau thiab cables.Cov qib nruab nrab mus rau qib siab molecular hnyav muaj qhov cuam tshuam zoo heev, txawm tias nyob hauv chav tsev kub thiab txawm tias qhov kub ntawm -40F.

HDPE yog cov thermoplastic polyolefin ua los ntawm copolymerization ntawm ethylene.Txawm hais tias HDPE tau tsim tawm hauv xyoo 1956, cov yas no tseem tsis tau mus txog qib kev paub tab.Cov khoom siv dav dav no niaj hnub tsim nws cov kev siv tshiab thiab kev lag luam.

Cov yam ntxwv tseem ceeb

HDPE yog non-polar thermoplastic resin nrog siab crystallinity.Cov tsos ntawm thawj HDPE yog milky dawb, thiab cov seem nyias yog translucent rau qee yam.PE muaj kev tiv thaiv zoo rau feem ntau cov tshuaj hauv tsev thiab kev lag luam.Qee hom tshuaj muaj peev xwm ua rau cov tshuaj corrosion, xws li corrosive oxidants (concentrated nitric acid), aromatic hydrocarbons (xylene) thiab halogenated hydrocarbons (carbon tetrachloride).Lub polymer yog non-hygroscopic thiab muaj dej vapor tsis kam, thiab tuaj yeem siv rau lub hom phiaj ntim.HDPE muaj cov khoom siv hluav taws xob zoo, tshwj xeeb tshaj yog lub zog dielectric siab ntawm rwb thaiv tsev, ua rau nws zoo heev rau cov xov hlau thiab cables.Cov qib nruab nrab mus rau qib siab molecular hnyav muaj qhov cuam tshuam zoo heev, txawm tias nyob hauv chav tsev kub thiab txawm tias qhov kub ntawm -40F.Cov yam ntxwv tshwj xeeb ntawm ntau qib ntawm HDPE yog kev sib xyaw ua ke ntawm plaub qhov sib txawv: qhov ntom ntom, qhov hnyav molecular, molecular hnyav faib thiab cov khoom ntxiv.Cov catalysts sib txawv yog siv los tsim cov polymers customized nrog cov khoom tshwj xeeb.Kev sib xyaw ua ke ntawm cov kev hloov pauv no tsim cov qib HDPE rau ntau lub hom phiaj;ua tiav qhov sib npaug zoo tshaj plaws hauv kev ua haujlwm.

ceev

Qhov no yog qhov sib txawv tseem ceeb uas txiav txim siab cov yam ntxwv ntawm HDPE, txawm hais tias plaub qhov sib txawv tau hais los cuam tshuam ib leeg.Ethylene yog cov khoom siv tseem ceeb ntawm polyethylene.Ob peb lwm cov comonomers, xws li 1-butene, 1-hexene los yog 1-octene, kuj feem ntau siv los txhim kho polymer kev ua tau zoo.Rau HDPE, cov ntsiab lus ntawm ob peb monomers saum toj no feem ntau tsis tshaj 1% -2%.Qhov sib ntxiv ntawm comonomer me ntsis txo cov crystallinity ntawm cov polymer.Qhov kev hloov no feem ntau ntsuas los ntawm qhov ceev, uas muaj kev sib raug zoo nrog crystallinity.Kev faib tawm dav dav ntawm Tebchaws Meskas yog raws li ASTM D1248, thiab qhov ceev ntawm HDPE yog 0.940g / .Saum C;Qhov ceev ntawm MDPE yog 0.926 ~ 0.940g / CC.Lwm qhov kev faib tawm qee zaum faib MDPE li HDPE lossis LLDPE.Homopolers muaj qhov ceev siab tshaj plaws, lub siab tawv tshaj plaws, zoo tshaj plaws permeability thiab feem ntau muaj kev ntxhov siab ib puag ncig kev ntxhov siab (escr).ESCR yog lub peev xwm ntawm PE tiv thaiv kev tawg los ntawm kev siv tshuab lossis tshuaj lom neeg.Ntau dua qhov tseem ceeb heev txhim kho cov neeg kho zog zog, xws li lub zog tensile, txhav txhav, thiab lub hardness;thermal zog xws li softening point kub thiab kub distortion kub;thiab impermeability, xws li huab cua permeability lossis dej vapor permeability.Qhov ntom ntom qis txhim kho nws qhov cuam tshuam lub zog thiab E-SCR.Polymer density feem ntau cuam tshuam los ntawm kev sib ntxiv ntawm comonomers, tab sis kom tsawg dua los ntawm qhov hnyav molecular.Qhov siab molecular hnyav feem pua ​​txo qhov ntom me ntsis.Piv txwv li, homopolymers muaj qhov sib txawv ntawm qhov sib txawv ntawm qhov hnyav molecular.

Kev tsim khoom thiab catalyst

Cov txheej txheem ntau lawm ntawm PE yog los ntawm slurry lossis roj theem ua, thiab ob peb yog tsim los ntawm cov txheej txheem kev daws teeb meem.Tag nrho cov txheej txheem no yog exothermic cov tshuaj tiv thaiv nrog ethylene monomer, a-olefin monomer, catalyst system (tej zaum yuav muaj ntau tshaj ib qho kev sib xyaw) thiab ntau hom hydrocarbon diluents.Hydrogen thiab qee cov catalysts yog siv los tswj qhov hnyav molecular.Lub slurry reactor feem ntau yog ib lub tank stirred los yog ntau dua siv loj-scale voj reactor nyob rau hauv uas cov slurry yuav tsum circulated thiab stirred.Thaum ethylene thiab comonomer (raws li xav tau) tuaj rau hauv kev sib cuag nrog cov catalyst, polyethylene hais yog tsim.Tom qab tshem tawm cov diluent, cov polyethylene granules los yog hmoov granules yog qhuav thiab cov additives yog ntxiv raws li ntau npaum li cas los tsim pellets.Cov kab ntau lawm niaj hnub nrog cov reactors loj nrog ntxaib ntsia hlau extruders tuaj yeem tsim ntau tshaj 40,000 phaus PE ib teev.Txoj kev loj hlob ntawm cov catalysts tshiab pab txhawb kev txhim kho cov qib tshiab ntawm HDPE.Ob hom catalysts feem ntau yog Philips 'chromium oxide-based catalysts thiab titanium compound-alkyl aluminium catalysts.HDPE tsim los ntawm Phillips catalyst muaj qhov nruab nrab-dav qhov hnyav molecular faib;titanium-alkyl aluminium catalyst muaj qhov nqaim molecular hnyav faib.Cov catalyst siv nyob rau hauv zus tau tej cov nqaim MDW polymers nyob rau hauv ib tug dual reactor kuj yuav siv tau los tsim dav MDW qib.Piv txwv li, ob lub reactors hauv series uas tsim cov khoom hnyav molecular sib txawv tuaj yeem tsim bimodal molecular hnyav polymers uas muaj ntau yam ntawm cov khoom hnyav molecular.PE yeeb nkab fittings

Molecular hnyav

Qhov hnyav dua molecular ua rau muaj viscosity ntawm polymer ntau dua, tab sis viscosity kuj tseem cuam tshuam nrog qhov kub thiab txias ntawm qhov siv hauv qhov ntsuas.Rheology lossis ntsuas qhov hnyav molecular yog siv los ntsuas qhov hnyav molecular ntawm cov khoom.Cov qib HDPE feem ntau muaj qhov hnyav molecular ntau ntawm 40 000 txog 300 000, thiab qhov hnyav nruab nrab molecular hnyav kwv yees sib piv rau qhov ntsuas qhov ntsuas kub, uas yog, los ntawm 100 txog 0. 029/10min.Feem ntau, siab dua MW (qis melt index MI) txhim khu lub zog yaj, zoo dua toughness thiab ESCR, tab sis siab dua MW ua rau kev ua.

Cov txheej txheem nyuaj dua los yog xav tau siab dua lossis kub.

Molecular weight tis (MWD): Lub WD ntawm PE txawv ntawm nqaim mus rau dav nyob ntawm tus catalyst siv thiab cov txheej txheem ua.

Qhov feem ntau siv MWD ntsuas ntsuas yog qhov ntsuas qhov tsis sib xws (HI), uas yog sib npaug rau qhov hnyav nruab nrab molecular hnyav (MW) muab faib los ntawm tus lej nruab nrab molecular hnyav (Mn).Qhov ntsuas qhov ntsuas no rau txhua qib HDPE yog 4-30.Qhov nqaim MWD muab kev ua tsov rog tsawg thiab muaj kev cuam tshuam loj thaum lub sij hawm molding txheej txheem.Qhov nruab nrab mus rau dav MWD muab cov txheej txheem rau feem ntau cov txheej txheem extrusion.Wide MWD kuj tuaj yeem txhim kho lub zog yaj thiab nkag mus.

tshuaj ntxiv

Qhov sib ntxiv ntawm cov tshuaj antioxidants tuaj yeem tiv thaiv kev degradation ntawm cov polymer thaum ua thiab tiv thaiv oxidation ntawm cov khoom tiav thaum siv.Antistatic additives yog siv nyob rau hauv ntau qib ntim los txo cov adhesion ntawm fwj los yog ntim rau plua plav thiab av.Cov ntawv thov tshwj xeeb yuav tsum muaj cov tshuaj ntxiv tshwj xeeb, xws li tooj liab inhibitors ntsig txog cov ntawv thov hlau thiab cable.Cov huab cua zoo heev thiab tiv thaiv ultraviolet (lossis tshav ntuj) tuaj yeem ua tiav los ntawm kev ntxiv cov tshuaj tiv thaiv UV.Yog tsis muaj qhov sib ntxiv ntawm UV-resistant lossis carbon dub PE, nws raug nquahu kom tsis txhob siv sab nraum zoov ntxiv.High-qib carbon dub pigments muab kev tiv thaiv UV zoo heev thiab feem ntau siv rau sab nraum zoov, xws li xov hlau, cables, tank txheej lossis kav dej.

kev ua

PE tuaj yeem tsim nyob rau hauv ntau hom kev sib txawv.Siv ethylene ua cov khoom siv tseem ceeb, propylene, 1-butene, thiab hexene li copolymer, nyob rau hauv qhov kev txiav txim ntawm catalyst, slurry polymerization los yog roj theem polymerization txheej txheem yog saws, thiab cov polymerization tau flashed, sib cais, qhuav, granulated. , thiab lwm yam txheej txheem kom tau cov khoom tiav nrog cov khoom sib xws.Xws li cov ntawv extrusion, zaj duab xis extrusion, yeeb nkab lossis profile extrusion, tshuab moulding, txhaj tshuaj molding thiab rotational molding.

▲ Extrusion: Cov qib siv rau extrusion ntau lawm feem ntau muaj qhov ntsuas yaj tsawg dua 1 thiab qhov nruab nrab-rau-dav MWD.Thaum ua tiav, qis MI tuaj yeem tau txais lub zog yaj tsim nyog.Cov qib MWD dav dua yog qhov tsim nyog rau extrusion vim tias lawv muaj kev tsim khoom ntau dua, txo qis kev tuag thiab txo cov pob txha tawg.

PE muaj ntau yam kev siv extrusion, xws li xov hlau, cables, hoses, kav thiab profiles.Kev siv yeeb nkab muaj ntau yam los ntawm cov kav dej me me rau cov pa roj rau cov kav dej tuab-walled dub nrog txoj kab uas hla ntawm 48in rau cov kav dej hauv nroog thiab hauv nroog.Kev siv cov kav dej loj-ntev hollow-phab ntsa los hloov cov kav dej los nag ua los ntawm cov pob zeb thiab lwm cov kav dej phwj tuaj loj hlob sai.

Sheet thiab thermoforming: Cov thermoforming hauv ob sab phlu ntawm ntau lub tub yees loj picnic yog ua los ntawm PE, uas yog tawv, lub teeb thiab ruaj khov.Lwm cov ntaub ntawv thiab cov khoom siv thermoformed muaj xws li mudguards, tank liners, pan guards, shipping thawv thiab tso tsheb hlau luam.Feem ntau ntawm daim ntawv thov kev loj hlob sai yog cov mulch lossis cov pas dej hauv qab cov zos, uas yog nyob ntawm qhov toughness, tshuaj tiv thaiv thiab impermeability ntawm MDPE.

▲ Tshuab moulding: Ntau tshaj 1/3 ntawm HDPE muag hauv Tebchaws Meskas yog siv rau tshuab moulding.Cov no muaj xws li los ntawm cov fwj uas muaj tshuaj dawb, roj cav, tshuaj ntxuav tes, mis nyuj thiab dej distilled mus rau lub tub yees loj, tsheb roj tank thiab canisters.Cov yam ntxwv ntawm cov tshuab moulding qib, xws li yaj lub zog, ES-CR thiab toughness, zoo ib yam li cov siv rau daim ntawv thiab thermoforming, yog li cov qib zoo sib xws tuaj yeem siv tau.

Kev txhaj tshuaj molding feem ntau yog siv los ua cov thawv me me (tsawg dua 16oz) rau ntim tshuaj, tshuaj zawv plaub hau thiab tshuaj pleev ib ce.Ib qho ntawm qhov zoo ntawm cov txheej txheem no yog tias cov fwj ntau lawm tau txiav txiav, tsis tas yuav tsum tau ua cov kauj ruam tom qab ua tiav zoo li kev tshuab molding.Txawm hais tias qee qhov nqaim MWD qib tau siv los txhim kho qhov chaw tiav, cov qib nruab nrab mus rau dav MWD feem ntau yog siv.

▲ Txhaj tshuaj molding: HDPE muaj ntau daim ntawv thov, xws li rov qab siv dua cov khob dej qab zib rau 5-gsl cov kaus poom, uas haus 1/5 ntawm HDPE hauv tsev.Cov qib txhaj tshuaj molding feem ntau muaj qhov ntsuas ntawm 5-10.Muaj cov qib nrog toughness thiab qis fluidity thiab ntau dua fluidity qib nrog processability.Kev siv suav nrog cov khoom siv niaj hnub thiab cov khoom noj uas nyias nyias ntim;Cov khoom noj tawv thiab ruaj khov thiab cov xim pleev xim;siab tsis kam mus rau ib puag ncig kev ntxhov siab tawg daim ntaub ntawv, xws li lub cav me me roj tso tsheb hlau luam thiab 90-gal khib nyiab cov kaus poom.

▲ Rotational molding: Cov ntaub ntawv siv txoj kev ua no feem ntau crushed rau hauv cov ntaub ntawv hmoov, uas yog melted thiab ntws nyob rau hauv lub thermal voj voog.Rotomolding siv ob hom PE: dav dav thiab sib txuas.General-purpose MDPE / HDPE feem ntau muaj qhov ceev ntawm 0.935 mus rau 0.945g / CC, nrog rau qhov nqaim MWD, kom cov khoom muaj kev cuam tshuam thiab tsis tshua muaj kev sib ntaus sib tua, thiab nws qhov Performance index yog feem ntau nyob rau hauv thaj tsam ntawm 3-8.Cov qib siab dua MI feem ntau tsis haum vim tias lawv tsis muaj qhov cuam tshuam thiab ib puag ncig kev ntxhov siab tawg ua rau cov khoom siv rotomolded.

Kev ua haujlwm siab rotational molding daim ntawv thov siv cov khoom tshwj xeeb ntawm nws cov qib sib txuas sib txuas.Cov qib no muaj qhov zoo fluidity nyob rau hauv thawj feem ntawm lub voj voog molding, thiab tom qab ntawd crosslink los tsim lawv qhov zoo tshaj plaws ib puag ncig kev ntxhov siab tawg thiab toughness.Hnav tsis kam thiab huab cua tsis kam.Cross-linkable PE tsuas yog tsim rau cov thawv loj, xws li 500-gal tanks rau thauj ntau yam tshuaj mus rau 20,000-gal cov tank ua liaj ua teb.

▲ Zaj duab xis: PE zaj duab xis ua feem ntau yog siv cov tshuab cua tshuab zoo tib yam lossis kev ua vaj huam sib luag.PE feem ntau yog siv rau zaj duab xis, dav dav PE (LDPE) lossis linear low-density PE (LLDPE) muaj.HDPE zaj duab xis qib feem ntau yog siv qhov twg superior stretchability thiab zoo heev impermeability yuav tsum tau.Piv txwv li, HDPE zaj duab xis feem ntau yog siv rau cov hnab ntim khoom, hnab ntim khoom noj thiab ntim khoom noj.

Khoom ua haujlwm

High-density polyethylene yog non-toxic, tasteless, thiab odorless dawb hais nrog ib tug melting point ntawm txog 130 ° C thiab ib tug txheeb ze ntom ntawm 0.941 rau 0.960.Nws muaj cov cua kub zoo thiab ua haujlwm txias, tshuaj lom neeg ruaj khov, siab rigidity thiab toughness, thiab zoo mechanical zog.Dielectric zog thiab ib puag ncig kev ntxhov siab tawg kuj zoo.

Ntim thiab khaws cia

Khaws kom deb ntawm qhov hluav taws kub thiab rwb thaiv tsev kub thaum khaws cia.Lub warehouse yuav tsum qhuav thiab huv si.Nws yog nruj me ntsis txwv tsis pub sib tov nyob rau hauv tej impurities, tshav ntuj thiab los nag.Kev thauj mus los yuav tsum tau muab khaws cia rau hauv qhov chaw huv, qhuav, npog cov tsheb lossis cov cab, thiab yuav tsum tsis txhob muaj cov khoom ntse xws li cov ntsia hlau hlau.Kev thauj mus los sib xyaw nrog cov nplaim hluav taws uas muaj ntxhiab hydrocarbons, halogenated hydrocarbons thiab lwm cov kuab tshuaj organic yog txwv nruj.

rov siv dua thiab rov siv dua

HDPE yog qhov loj tshaj plaws ntawm kev lag luam yas rov ua dua tshiab.Qhov no feem ntau yog vim nws qhov yooj yim reprocessing, tsawg degradation yam ntxwv thiab nws cov ntaub ntawv loj rau lub hom phiaj ntim.Qhov tseem ceeb ntawm kev rov ua dua tshiab yog rov ua dua 25% ntawm cov khoom siv rov ua dua tshiab, xws li cov khoom siv rov qab siv dua tshiab (PCR), nrog HDPE ntshiab los ua lub raj mis uas tsis sib cuag nrog cov khoom noj.

PE kav dej rau dej yog cov khoom siv hloov cov kav dej ib txwm siv thiab cov kav dej PVC.