Polypropylene yog cov thermoplastic polymer ntawm propene. Nws yog tau los ntawm cov cuab yeej ntawm propylene polymerization siv hlau complex catalysts. Cov kev txwv rau kev tsim cov khoom siv no zoo ib yam li cov khoom tsim cov polyethylene tsawg-density.
Nyob ntawm seb cov catalyst siv, txhua hom polymer lossis sib tov ntawm no tuaj yeem tau txais. Lub melting point ntawm polypropylene yog ib qho ntawm cov yam ntxwv tseem ceeb ntawm cov khoom no. Nws muaj daim ntawv ntawm cov hmoov dawb los yog granules, qhov loj ntawm qhov sib txawv ntawm 0.5 g / cm³. Cov khoom piav qhia tuaj yeem dyed, stabilized lossis undyed.
Specifications: molecular qauv
Raws li cov qauv molecular, polypropylene tau muab faib ua ntau hom, ntawm lawv:
- isotactic;
- atactic;
- syndiotactic.
Stereoisomers ntawm cov khoom sib txawv ntawm lub cev,mechanical thiab chemical yam ntxwv. Piv txwv li, atactic polypropylene muaj qhov zoo ntawm cov khoom siv roj hmab, uas yog tus cwj pwm los ntawm kev muaj dej ntau. Lub melting kub ntawm polypropylene rau extrusion nyob rau hauv cov ntaub ntawv no yog kwv yees li 80 ° C, thaum lub ceev yuav ncav cuag 850 kg / m³.
Cov khoom no dissolves zoo heev hauv diethyl ether. Cov khoom ntawm isotactic polypropylene txawv ntawm cov lus piav qhia saum toj no thiab muaj cov qauv siab ntawm elasticity, nws qhov ceev ncav cuag 910 kg / m³, thaum lub melting point ntawm 165 txog 170 ° C. Hauv ntau yam no, polypropylene yog tus cwj pwm los ntawm kev ua haujlwm zoo rau cov tshuaj.
Lub cev thiab cov cuab yeej cuab tam
Hnub no, kev siv cov polypropylene ntau heev. Lub melting point ntawm cov khoom no txawv nyob rau hauv ib tug neeg ntau yam. Feem ntau nws tau muab piv nrog polyethylene, tab sis polypropylene tsis muaj qhov ntom ntom ntom, nws yog 0.91 g / cm³. Tsis tas li ntawd, polypropylene yog ib qho nyuaj, abrasion resistant, thiab kub resistant.
Nws qib softening pib ntawm ib ncig ntawm 140 ° C, thaum lub melting point mus txog 175 ° C. Cov khoom siv tsis raug rau corrosion cracking. Nws tiv taus cov pa oxygen thiab lub teeb, tab sis qhov rhiab heev no txo qis yog tias cov stabilizers ntxiv rau cov khoom xyaw hauv kev tsim cov polypropylene.
Ntau ntau yam ntawm polypropylene tau siv ntau yam kev lag luam niaj hnub no. Kubmelting ntawm cov khoom no nthuav dav. Elongation ntawm kev tawg raws li feem pua ntawm qhov sib txawv ntawm 200 txog 800%. Lub zog tensile tawm los yog sib npaug ntawm qhov txwv ntawm 250 txog 350 kgf / cm². Qhov kev cuam tshuam lub zog sib txawv ntawm 33 txog 80 kgf cm / cm², thaum Brinell hardness ranges ntawm 6 txog 6.5 kgf / mm².
Basic chemical properties
Yog tias koj npaj yuav yuav qee yam khoom ua los ntawm polypropylene, koj yuav tsum paub qhov melting point ntawm cov khoom no. Nws yog tham nyob rau hauv tsab xov xwm. Los ntawm nws koj tuaj yeem kawm lwm yam tshuaj lom neeg. Piv txwv li, cov khoom yog chemically ruaj khov, thiab nyob rau hauv cov organic solvents nws swells me ntsis. Yog hais tias qhov kub nce mus txog 100 ° C, cov khoom yuav yaj nyob rau hauv aromatic hydrocarbons. Hauv qhov no, peb tab tom tham txog toluene thiab benzene.
Vim tias polypropylene muaj tertiary carbon atoms, nws tiv taus oxygen, hluav taws xob ultraviolet thiab kub siab. Qhov no ua rau muaj kev nyiam rau kev laus piv rau polyethylene. Raws li kev cuam tshuam ntawm ib puag ncig nruj, polypropylene tsis tawg ntau npaum li polyethylene ua. Nws muaj peev xwm ua tiav qhov kev ntsuam xyuas tawg txawm tias muaj kev ntxhov siab.
Melting point ntawm polypropylene kav
Ntau zaus, cov neeg siv khoom niaj hnub no txaus siab rau qhov kub thiab txias ntawm polypropylene. cev osiv yog tias koj npaj yuav ua tiav qhov kev npaj ntawm cov cua sov. Thaum raug kub ntawm 140 ° C, cov khoom yuav muag muag, thaum nws poob nws cov duab. Yog hais tias qhov kub nce mus txog 170 ° C, ces lub melting theem yuav pib. Nyob rau tib lub sijhawm, nws yuav tsis nyuaj thiab yuav plam lub peev xwm los tswj nws cov yam ntxwv thiab cov duab.
Cov tshuab cua sov tsis yog tsim los rau qhov ntsuas kub zoo li no, yog li ntawd, cov kav dej polypropylene tsim nyog rau kev muab dej rau lub cev. Cov neeg tsim khoom feem ntau hais tias qhov kub siab tshaj plaws rau cov kav dej polypropylene yog 95 ° C. Cov khoom muaj peev xwm tiv taus qhov kub thiab txias, tab sis rau lub sijhawm luv luv. Yog tias cov kav dej siv tau ntev ntev ntawm qhov kub siab tshaj 100 ° C, ces lawv lub neej kev pab yuav txo qis.
Thaum kub hloov pauv, polypropylene yuav hloov loj. Thaum rhuab, nws yuav nthuav, thiab thaum txias, nws yuav shrink. Raws li qhov kub ntawm qhov kub, cov kav dej yuav pib sag nruab nrab ntawm cov fasteners, thiab koj yuav pom o nyob rau hauv txheej txheej.
Cov nuances ntawm kev siv cov kav dej polypropylene
Koj tuaj yeem siv cov khoom siv polypropylene. Lub melting kub ntawm cov kav dej no tuaj yeem sib txawv. Qhov no yuav tsum tau coj mus rau hauv tus account yog tias koj muaj cov khoom ntawm PN20 hom nyob rau hauv pem hauv ntej ntawm koj. Hauv qhov no, peb tab tom tham txog cov yeeb nkab uas nws qhov kev ua haujlwm kub txog 60 ° C. Tab sis yog tias peb tab tom tham txog cov khoom lag luam PN25, qhov no qhia tau hais tias nws yuav tuaj yeem tiv taus kub txog 95 ° C.
Zoo kawg
Speb tuaj yeem hais nrog qhov tseeb tias tso polypropylene nyob ze ntawm cov pa luam yeeb tau tso cai. Lub melting point ntawm polypropylene, txawm li cas los xij, tsis qhia tias cov kav dej yuav tsum tsis txhob tiv thaiv. Cov kws tshaj lij pom zoo kom yuav cov khoom siv ntxiv uas tsis tshua muaj kev cuam tshuam rau deformation thaum raug kub siab. Yog li ntawd, cov kav dej yuav tsum tau muaj kev tiv thaiv ntxiv los ntawm kev rwb thaiv tsev thiab muaj cov fiberglass sab hauv lossis aluminium txheej. Qhov no yuav tiv thaiv cov kav dej los ntawm kev nthuav dav thiab ua rau lawv lub neej ua haujlwm ntev.
