Kev txau ntawm cov polymers uas twb muaj lawm feem ntau siv rau kev npaj ntawm cov ntaub ntawv tshiab. Tau ntau xyoo, ntau lub tshuab tau tsim kho thiab ua lag luam.
Qhov loj ntawm polymeric blends yog raws li polyolefins, uas yog cov tshuaj siv ntau tshaj los siv polymers hauv kev lag luam.Low-ntuag polyethylenes (LDPEs) feem ntau siv hauv kev lag luam. Lawv muaj qhov cuam tshuam zoo zog, tsis tshua muaj brittleness kub, yoog raws, zaj duab xis pob tshab thiab zoo nkauj hluav taws xob-rwb thaiv tsev. Cov kev lag luam loj yog nyob hauv cov khoom lag luam ntim khoom noj, cov ntawv ntim khoom lag luam thiab lub hnab ntim khoom pov tseg.
Cov nplaim hluavtaws (Fischer – Tropsch synthesis) yog cov xim dawb, translucent, tsis qab thiab tsis hnov ntxhiab uas muaj qhov sib xyaw ntawm cov roj hydrocarbons ntawm lub cev hnyav. Lawv tsis soluble nyob rau hauv ntau cov kuab tshuaj vim lawv lub siab khov, tab sis lawv yaj hauv dej xylene, xws li LDPE. Lawv siv, inter alia, rau qhov
npaj cov tswm ciab, ntawv txheej, tiv thaiv kev tiv thaiv rau cov khoom lag luam thiab dej haus, biodegradable mulch, nres rau cov kua txiv acid, hluav taws xob rwb thaiv tsev thiab lwm yam. Lawv muaj yaj tsis qab viscosity thiab lub siab ncaj ncaj hydrocarbon saw cim.
npaj cov tswm ciab, ntawv txheej, tiv thaiv kev tiv thaiv rau cov khoom lag luam thiab dej haus, biodegradable mulch, nres rau cov kua txiv acid, hluav taws xob rwb thaiv tsev thiab lwm yam. Lawv muaj yaj tsis qab viscosity thiab lub siab ncaj ncaj hydrocarbon saw cim.
Kev sib hla sib txuas yog txoj kev siv dav siv rau kev hloov pauv ntawm cov khoom polymer. Cov txheej txheem no cuam tshuam nrog kev tsim cov kab ua peb-txheej, cov gels, ua rau muaj kev hloov pauv ntau yam hauv cov khoom siv.Qhov txheej txheem yuav raug siv rau kev pib ua ntawm polyolefin sib txuas sib txuas. Ib ntawm lawv yog raws kev tsim macroradical ntawm thermal decomposition ntawm cov organic peroxides.A cov ncauj lus kom ntxaws ntawm ntau cov txheej txheem pib tau muab nyob rau hauv kev tshuaj xyuas txhua yam los ntawm Lazar et al.
Hauv daim ntawv no peb yuav tsum tham txog qee qhov thermal thaj chaw xws li melting temperature, crystallization temperature, nrog rau tshwj xeeb melting thiab crystallization enthalpies ntawm cross-linked LDPE / siv quav ciab thiab lawv txoj kev cia siab rau qhov kev xa khoom ntawm tus neeg sawv cev sib txuas (dicumyl peroxide) thiab ciab cov ntsiab lus. Raws li kev siv ntau yam ntawm LDPE / siv quav ciab blends muaj kev txhawj xeeb, qis viscosity ntawm yaj (ntawm qhov kub qis dua qhov ua tau zoo-kev sib txuas ua haujlwm kub) thiab dej tsis zoo tuaj yeem xav tau.
Yog hais tias cov ciab ntsiab lus nce, cov ntsiab lus ntawm gel tom qab kev sib txuas sib txuas txo, vim tias siv quav ciab xav tau ntau dua qhov kev xav ntawm peroxide rau kev sib txuas thiab yog li ntawd tsuas yog nyob rau theem PE sib txuas sib txuas. Kev sib txuas sib txuas nrog 2% ntawm DCP yog qhov muaj txiaj ntsig ntau dua, tab sis tseem tsuas yog qib PE ntawm qhov kev sib txuas.
DSC nkhaus rau ob leeg 0.5% DCP thiab 2% DCP qhia tsuas yog ib qhov kawg ntawm lub ntsej muag rau cov kev sib tov nrog 5 thiab 10% ciab, txawm tias qhov tseeb tias siv quav ciab ntshiab muaj peb qhov siab tshaj. Cov lus piav qhia tshwm sim yog LDPE thiab siv quav ciab yog qhov tsis zoo nyob hauv qib crystalline theem12 hauv cheeb tsam thaj chaw no. Lub ntsiab ntawm qhov xaus endothermic kawg yog nyob ntawm 100 ° C thiab qhov pom muaj ciab tsis cuam tshuam rau nws txoj haujlwm. Los ntawm 20% ciab peb saib ib pliag thib ob, dav ncov ntawm kwv yees li 80 ° C. Lub ncov no tej zaum ua ib feem ntawm qhov ciab melting endotherm. Qhov no txhais tau tias LDPE thiab siv quav ciab tsuas yog qee qhov kev ua haujlwm tsis zoo nyob hauv thaj chaw no.