PMMA Yas: Nws yog dab tsi?

1. PMMA yas yog dab tsi?

PMMA yas sawv cev rau Poly Methyl Methacrylate. Nws yog ib hom ntawmengineering yasuas yog pob tshab, paub txog nws qhov yooj, thiab yog siv los hloov iav. Thaum rhuab mus rau qhov kub siab, cov yas softens mus rau hauv lub xeev ua kua. Txawm li cas los xij, thaum txias, nws tuaj yeem ua kom rov qab sai dua.

PMMA cov khoom siv yas kuj tseem paub los ntawm lwm lub npe xws li plexiglass lossis Mica yas. Nyob ntawm qhov kev npaj siv thiab kev xav txog nyiaj txiag, koj tuaj yeem xaiv hom khoom tsim nyog tshaj plaws.

 

2. Cov qauv ntawm PMMA yas

PMMA yas yog tsim los ntawm cov txheej txheem polymerization ntawm methyl methacrylate (MMA) monomers. MMA monomer muaj cov qauv molecular ntawm C5H8O2 lossis CH2=CCH3COOCH3. Nws muaj ib tug fibrous molecular qauv, teem nyob rau hauv ib tug spatial network. Cov qauv no txhawb nqa PMMA lub zog txhua yam, siab tawv tawv, thiab ua haujlwm zoo heev rau kev puas tsuaj.

PMMA yog linear polymer, qhov twg MMA monomers txuas ua ke los ntawm ester bonds. Cov ester daim ntawv cog lus no muaj zog heev thiab kub-resistant.

 

3. PMMA ua li cas?

PMMA, tseem hu ua acrylic lossis plexiglass, yog cov thermoplastic polymer tsim los ntawm polymerizing methyl methacrylate (MMA). MMA yog cov monomer siv hauv kev tsim PMMA. MMA yog ib qho organic compound nrog cov tshuaj formula CH2=C(CH3)COOCH3. Nws yog cov kua uas tsis muaj xim, tsis muaj ntxhiab tsw. MMA yog tsim los ntawm copolymerization ntawm acryloyl chloride nrog methanol.

Lub polymerization ntawm MMA tuaj yeem ua tiav siv ntau txoj hauv kev, suav nrog:

-Thermal Polymerization: Qhov no yog txoj hauv kev zoo tshaj plaws los tsim PMMA. MMA yog cua sov kom sov, feem ntau nyob ib ncig ntawm 100-150 degree . Ntawm qhov kub no, MMA molecules pib sib xyaw ua ke los tsim cov saw hlau polymer.

-Catalytic Polymerization: Txoj kev no siv cov catalyst los pib txheej txheem polymerization. Cov catalyst tshaj plaws yog benzoyl peroxide.

-Radiation Polymerization: Txoj kev no siv ultraviolet lossis X-ray hluav taws xob los ua cov txheej txheem polymerization.

 

4. PMMA yas khoom

PMMA yas yog dav siv nyob rau hauv ntau yam teb vim nws txawv qhov zoo. Hauv qab no yog cov yam ntxwv tseem ceeb ntawm PMMA:

-PMMA yas yog kwv yees li 40% sib zog dua iav thiab ntau dua 10 npaug zog dua li iav.

-Nws muaj kev tiv thaiv rau kev puas tsuaj, thiab huab cua puag, nrog rau kev tiv thaiv rau dilute acids, alkalis, ntsev, thiab cov kuab tshuaj organic.

-PMMA polymer muaj qhov ntsuas qhov taw qhia ntawm 1.49, muab lub teeb kis tau zoo. Ib daim ntawv PMMA tso cai rau 92% ntawm lub teeb hla, ntau dua li iav lossis lwm yam yas.

-PMMA yas muaj cov cua kub tsis tshua muaj zog, tuaj yeem tiv taus qhov kub ntawm 60 txog 80 degrees.

-Celsius yog cov yam ntxwv ntawm ntau cov yas, thiab PMMA tsis muaj qhov tshwj xeeb.

-Nws yog resistant rau ultraviolet hluav taws xob thiab muaj qis infrared kis tau tus mob piv rau iav.

-PMMA tsis cuam tshuam los ntawm cov dej ntsev thiab cov tshuaj alkaline.

-Nws muaj cov khoom siv hluav taws xob zoo insulating, tshwj xeeb tshaj yog nyob rau tsawg zaus.

-Txawm li cas los xij, PMMA muaj qhov cuam tshuam rau kev puas tsuaj thiab o thaum sib cuag nrog qee cov kuab tshuaj xws li H2O2, Acetone, thiab Cawv ...

-PMMA yog ib qho tawv, ruaj, thiab lub teeb yuag thermoplastic. Qhov ceev ntawm acrylic yog li ntawm 1.17 mus rau 1.20 g / cm3, uas yog tsawg tshaj li ib nrab ntawm iav.

-Nws muaj kev khawb zoo heev thaum piv rau lwm cov pob tshab polymers zoo li Polycarbonate tab sis tsis muaj khawb-resistant dua iav.

-PMMA muaj peev xwm nqus dej tsawg thiab nqus dej, ua kom cov khoom tsim los ntawm PMMA tswj qhov zoo ntawm qhov ntev.

 

5. Sib piv PMMA thiab PC

Ob leeg PMMA thiab PC yog cov thermoplastic polymers, txhais tau tias lawv tuaj yeem ua kom sov thiab hloov kho ntau zaus yam tsis muaj kev puas tsuaj. Lawv ob leeg muaj kev ua haujlwm siab thiab muaj kev cuam tshuam zoo, thiab lawv kuj tuaj yeem ua rau huab cua tsis zoo.
PMMA thiab PC yog ob hom thermoplastic polymers dav siv hauv ntau daim ntawv thov. Txawm li cas los xij, muaj qee qhov sib txawv ntawm cov yas no.

-Transparency: PMMA yog pob tshab dua li PC. Qhov no ua rau PMMA qhov kev xaiv zoo dua rau cov ntawv thov uas xav tau qhov pom tseeb, xws li tsom iav, tsom iav, thiab kos npe.

-Heat Resistance: PMMA muaj cua sov siab dua li PC. Qhov no txhais tau tias PMMA tuaj yeem tiv taus qhov kub siab dua yam tsis muaj deforming lossis puas.

-Corrosion Resistance: PMMA muaj corrosion kuj zoo dua li PC. Qhov no ua rau PMMA qhov kev xaiv zoo dua rau cov ntawv thov hauv ib puag ncig hnyav, xws li kev lag luam tshuaj.

-Tus nqi: PMMA feem ntau kim dua li PC.

Qhov kev xaiv ntawm cov yas no nyob ntawm cov kev cai tshwj xeeb ntawm daim ntawv thov. Yog tias pob tshab, tiv thaiv tshav kub, lossis tiv thaiv corrosion yog qhov tseem ceeb, ces PMMA yog qhov kev xaiv zoo dua. Yog tias tus nqi yog qhov tseem ceeb, ces lub PC yog qhov kev xaiv zoo dua.