Polycarbonatezaum ntawm kwv yees li 1.20 txog 1.22 g / cm³-ib daim duab uas tsis rub cov xov xwm tab sis ntsiag to txiav txim siab seb koj lub tsom iav kev nyab xeeb puas muaj kev cuam tshuam, seb lub qhov rais dav hlau tuav ntawm qhov siab, thiab seb lub xov tooj smartphone puas tiv thaiv dab tsi. Cov thermoplastic qhov ntom ntom no qhia txog nws qhov kev ntim khoom molecular, kev nruj ntawm bisphenol A units txuas los ntawm carbonate pawg. Engineers tsis xaiv polycarbonate rau nws glamour. Lawv xaiv nws vim qhov tshwj xeeb qhov ceev no - rau - kev ua tau zoo piv daws teeb meem lwm cov yas kov tsis tau.
Cov lej tom qab cov khoom siv
Cov neeg feem ntau saib ntawm qhov ceev specifications thiab txav mus. Ncaj ncees txaus. Tab sis ntawm no yog dab tsi uas 1.2 g / cm³ txhais tau tias nyob rau hauv cov ntsiab lus tswv yim.
Muab piv rau acrylic ntawm 1.18 g / cm³. NW nyuam qhuav muaj qhov sib txawv, txoj cai? Txawm li cas los xij, polycarbonate tuav cov khoom cuam tshuam uas yuav ua rau acrylic tawg rau hauv cov khoom txaus ntshai. Qhov ntom ntom zoo sib xws npog tag nrho cov cwj pwm sib txawv ntawm cov molecular hauv kev ntxhov siab. Polycarbonate's chains tuaj yeem nqus tau lub zog los ntawm kev txav molecular- lawv swb, lawv ncab, lawv rov faib zog. Acrylic xwb... tawg.
iav khiav ncig 2.5 g / cm³. Yog li polycarbonate muab koj kwv yees li ib nrab ntawm qhov hnyav nrog kev cuam tshuam zoo heev. Kev lag luam -offs muaj, pom tseeb. Scratch kuj tsis zoo. UV stability yuav tsum tau additives. Tab sis rau cov ntawv thov uas qhov hnyav hnyav thiab tsis ua haujlwm tsis yog ib qho kev xaiv, qhov ntom ntom kom zoo dua sib txuas thoob plaws txhua square meter ntawm cov khoom.
Qhov hnyav suav tau tiag
Kuv tau saib cov engineers siv sij hawm rau qhov hnyav pob nyiaj siv rau cov khoom siv hauv aerospace. Txhua gram suav thaum koj tawm tsam lub ntiajteb txawj nqus. Polycarbonate qhov ceev cia koj xam cov luj vaj huam sib luag nrog qhov tsim nyog precision:
Ib daim ntawv ntsuas 1 meter × 1 meter × 6mm tuab hnyav kwv yees li 7.2 kg. Hloov qhov ntawd rau iav ntawm qhov sib npaug optical clarity? Koj saib 15 kg. Rau ib lub vaj huam sib luag. Tam sim no muab faib thoob plaws ib lub dav hlau dav hlau lossis tsev cog khoom installation.
Lub tshuab hluav taws xob tau ntes tau mus rau qhov no ntau xyoo dhau los. Panoramic sunroofs, headlight lenses, sab hauv Cheebtsam -polycarbonate shaved hnyav yam tsis muaj kev cuam tshuam cov txheej txheem. Txawm hais tias ncaj ncees, qee cov tuam txhab lag luam tau thawb cov khoom dhau ntawm nws cov kev txwv hauv kev siv thaum ntxov. Kev kawm nkhaus muaj.
Molecular Density thiab Impact Performance
Qhov kev sib txuas no tsis tau sib tham txaus sab nraum lub voj voog.
Polycarbonate qhov ntom ntom qhia tau li cas nws cov saw hlau polymer ntim ua ke hauv lub xeev ruaj khov. Tsis crystalline -polycarbonate nyob twj ywm amorphous, txhais tau tias tsis muaj cov qauv siv lead ua. Cov chains tangle thiab interweave me ntsis random. Qhov no amorphous qauv, ntawm qhov tshwj xeeb ntom, tsim ib yam dab tsi zoo kawg li: lub peev xwm los tawm los ua ntej tawg.
Thaum ib yam dab tsi hits polycarbonate nto, cov khoom deforms. Lub zog kis tau los ntawm kev txav ntawm cov saw hlau es tsis yog tsom rau ntawm cov ntsiab lus tawg. Qhov ceev tseem ceeb txiav txim siab npaum li cas cov khoom muaj nyob rau nqus lub zog ntawm ib chav tsev ntim.
Cov qauv ntsuas zoo li ANSI Z87.1 rau cov looj tsom iav muaj kev nyab xeeb muaj ib feem vim tias polycarbonate ua rau siab - cuam tshuam kev tiv thaiv kev lag luam. Ua ntej polycarbonate tau dhau los ua ib qho, tsom iav kev nyab xeeb txhais tau tias iav hnyav nrog kev tiv thaiv tsawg lossis cov yas flimsy uas ua tsis tau thaum koj xav tau tiag tiag.
Thermal Behavior Ties Rov qab mus rau qhov ntom ntom
Cua sov polycarbonate hloov txhua yam txog nws qhov ntom. Tsis zoo heev-peb tab tom tham txog feem pua ntawm ib feem pua -tab sis txaus los cuam tshuam rau cov ntawv thov raug.
Ntawm chav tsev kub: ~ 1.20 g / cm³. Tshav kub rau nws cov iav hloov pauv kub ntawm 147 degree, thiab molecular zog nce. Chains xav tau chaw ntxiv. Qhov ntom ntom me ntsis. Qhov kev nthuav dav thermal no yuav tsum tau tsim nyob ib puag ncig hauv cov ntawv thov uas muaj qhov kub thiab txias.
Kev teeb tsa sab nraum zoov hauv cov huab cua hauv suab puam pom qhov ntsuas kub txhua hnub ntawm 40℃lossis ntau dua. Mounting systems yuav tsum tau raws li qhov tshwm sim ntawm qhov kev hloov pauv. Rigid mounting ua rau kev nyuaj siab buildup, nws thiaj li tawg, tsis ua hauj lwm ntxov ntxov. Qhov tshwj xeeb ntom ntom ib leeg tsis ntes qhov no - koj xav tau thermal expansion coefficients ib yam nkaus -tab sis lawv tau sib txuas nrog kev coj tus cwj pwm molecular.
Kev txiav txim siab ceev ceev
Txhaj tshuaj molders mob siab txog polycarbonate ntom, tab sis yog vim li cas tej zaum yuav tsis pom tseeb.
Melt density txawv ntawm cov khoom ntom ntom. Thaum polycarbonate ntws los ntawm kev txhaj tshuaj molding tshuab ntawm 280-320 degree, nws nthuav. Xam qhov ntau thiab tsawg ntawm txhaj tshuaj, tswj lub qhov rooj khov, kwv yees shrinkage-tag nrho cov no nyob ntawm kev nkag siab txog kev hloov pauv li cas los ntawm kev ua.
Ib txwm shrinkage khiav 0.5-0.7% rau polycarbonate unfilled. Ntxiv cov iav fibers thiab koj hloov qhov sib npaug ntawm qhov sib npaug nkaus. Cov qib iav ntim tau ntaus 1.35-1.52 g / cm³ nyob ntawm qib thauj khoom. Txawv shrinkage qauv. Sib txawv warpage tendencies. Txawv txhua yam.
Moulders uas tsis quav ntsej txog qhov ceev no -txoj kev coj cwj pwm tsim cov khoom uas tsis ua raws li qhov loj me. Los yog phem dua, qhov chaw uas ua tau raws li qhov loj me tab sis warp dhau lub sij hawm raws li residual stresses so.
Filled Versus Unfilled: A Density Story
Iav fiber reinforcement transforms polycarbonate cov khoom zoo heev uas nws yuav luag dhau los ua cov khoom sib txawv.
| Qib Hom | Hom ntom ntom | Key Trade- tawm |
|---|---|---|
| Tsis muaj PC | 1.20 g / cm³ | Qhov zoo tshaj plaws optical clarity, siab tshaj qhov cuam tshuam |
| 10% iav- puv | 1.28 g / cm³ | Txhim kho qhov tawv nqaij, txo ductility |
| 20% iav- puv | 1.35 g / cm³ | Qhov tseem ceeb tawv nce, anisotropic zog |
| 30% iav- puv | 1.43 g / cm³ | Nyob ze ntawm cov qauv muaj peev xwm, txwv elongation |
Qhov ceev nce vim iav khiav txog 2.5 g / cm³. Cov kev cai sib xyaw yooj yim siv tau, kwv yees. Dab tsi tsis ua raws li cov cai yooj yim: cov cuab yeej cuab tam hloov pauv. Cov iav fibers tsim kom muaj kev ntxhov siab. Kev cuam tshuam tsis kam poob, qee zaum kev puas tsuaj. Txoj kev zoo nkauj zoo nkauj tsis ua haujlwm ntawm polycarbonate tsis ua tiav muab txoj hauv kev rau tus cwj pwm nkig.
Kuv tau pom cov neeg tsim qauv qhia cov iav- tau ntim cov polycarbonate rau cov ntawv thov cuam tshuam vim "polycarbonate txhais tau tias cuam tshuam." Nws tsis yog ib txwm ua haujlwm li ntawd.
Specific Gravity Versus Density-Ib qho tangent tsim nyog
Cov ntsiab lus no tau siv sib hloov. Lawv yuav tsum tsis yog.
Qhov ceev muaj units: g / cm³, kg / m³, lb / ft³. Lub ntiajteb txawj nqus tshwj xeeb yog dimensionless-nws yog ib qho piv txwv piv cov khoom qhov ntom ntom rau cov dej ntom ntom ntawm qhov ntsuas kub. Rau polycarbonate, ob tus lej tshwm sim sib npaug li 1.20 vim tias cov dej ntom ntom ntawm cov txheej txheem yog qhov tseem ceeb 1.0 g / cm³.
Qhov tsis meej pem tsis tshua muaj teeb meem rau cov yas denser dua dej. Tab sis nws tsim teeb meem thaum sib piv cov ntaub ntawv thoob plaws hauv chav tsev, los yog thaum cov lus qhia meej yuav tsum muaj qhov tseeb loj -ib - ntim qhov tseem ceeb es tsis yog qhov sib piv.
Cov ntawv txheeb xyuas cov ntaub ntawv qee zaum qhia txog lub ntiajteb txawj nqus, qee zaum ceev, qee zaum ob qho tib si. Nco ntsoov xyuas cov units. Ib txwm txheeb xyuas cov xwm txheej siv.
Floatation thiab Density Test
Kev ntsuas ceev ceev rau cov khoom zoo: nws puas nyob hauv dej?
Polycarbonate ntawm 1.20 g / cm³ dab dej. Yog tias koj tus qauv "polycarbonate" ntab, koj muaj teeb meem. Txawm hais tias nws tsis yog polycarbonate, los yog nws muaj cov voids tseem ceeb, los yog ib tug neeg dag txog cov khoom specifications. Qhov kev sim float yooj yim no ntes tau qhov yuam kev tag nrho tab sis yuav tsis pom qhov hloov pauv hloov pauv hloov pauv hauv cov kev txwv tshwj xeeb.
Rau kev ntsuas qhov ceev, cov kab gradient lossis pycnometers muab kev daws teeb meem zoo dua. Incoming inspection programs at serious manufacturers include density verification for exactly this reason-density variations can signal molecular weight differences, contamination, or degradation.
Optical Applications Demand Density Consistency
Cov tsom iav tsom iav, cov lus qhia teeb pom kev zoo, kho qhov muag discs- cov ntawv thov no zam yuav luag tsis muaj qhov sib txawv ntawm qhov sib txawv vim qhov kev hloov pauv cuam tshuam nrog cov teeb meem kho qhov muag.
Density inconsistencies in polycarbonate typically mean one of several problems: moisture contamination during processing, thermal degradation creating volatile byproducts, incomplete melting leaving unincorporated material, or contamination from other polymers. Txhua tus tsim optical distortions. Ib txhia tsim haze. Qee qhov tsim qhov ntsuas qhov ntsuas qhov ntsuas hauv cheeb tsam sib txawv uas tshwm sim raws li cov khoom siv pom txawv txawv.
The original compact disc specification required polycarbonate meeting tight density tolerances precisely because optical storage depends on consistent light transmission. DVD thiab Blu-ray thawb cov kev xav tau nruj dua.
Dab tsi ceev yuav tsis qhia koj
Ntawm no yog qhov hais txog specifications. Qhov ntom ntom yog ib tus lej. Cov khoom lag luam ua tiav lossis tsis ua tiav raws li ntau ntau ntawm cov khoom sib cuam tshuam.
Qhov ntom ntom tsis kwv yees UV tsis kam. Polycarbonate degrades nyob rau hauv ultraviolet raug, yellowing thiab ua nkig dhau sij hawm tsis muaj stabilizers. Tib qhov ceev ua ntej thiab tom qab degradation (kwv yees), kev ua haujlwm sib txawv kiag li.
Qhov ntom tsis kwv yees cov tshuaj tiv thaiv. Polycarbonate yaj nyob rau hauv ntau cov kuab tshuaj-acetone yog tus piv txwv nto moo uas ua rau tib neeg xav tsis thoob. Aromatic hydrocarbons ua rau muaj kev ntxhov siab tawg. Tsis muaj qhov no tshwm sim hauv kev ntsuas qhov ceev.
Qhov ntom ntom tsis kwv yees ntev ntev - tus cwj pwm nkag mus, lub neej qaug zog, lossis ib puag ncig kev ntxhov siab tawg tsis kam. Cov no yuav tsum muaj kev sim cais, cais cov kev qhia tshwj xeeb, cais cov kws tshaj lij.
Environmental Angles
Polycarbonate qhov ntom ntom tsim cov teeb meem rov ua dua tshiab uas tsis tau txais kev saib xyuas txaus.
Ntawm 1.20 g / cm³, polycarbonate dab dej hauv dej-raws li kev sib cais, tsaws hauv tib seem li PET (1.38 g / cm³) thiab lwm yam "hnyav" plastics. Kev txheeb cov thev naus laus zis yuav tsum siv txoj hauv kev ntxiv -infrared spectroscopy, electrostatic sib cais, phau ntawv txheeb xyuas -kom cais cov polycarbonate los ntawm cov kwj sib xyaw.
Kev lag luam feem ntau tsis ua haujlwm. Virgin polycarbonate tsis yog tshwj xeeb yog pheej yig, tab sis nws pheej yig txaus uas cov khoom siv rov ua dua tawm tsam kev sib tw, tshwj xeeb tshaj yog thaum cov kev xav tau purity rau kev siv kho qhov muag lossis kev nyab xeeb tshem tawm feem ntau tshaj tawm - cov neeg siv khoom.
Kev suav cov ntaub ntawv ntom ntom rau hauv lub neej- kev ntsuas lub voj voog ib yam nkaus. Shipping cov ntaub ntawv sib zog txhais tau hais tias kev thauj mus los qis dua ib chav ua haujlwm, piv txwv li kev ua haujlwm sib npaug. Polycarbonate qhov nruab nrab ntom ntom pab ntawm no piv rau iav, mob piv rau qis dua - ntom ntom polymers zoo li polypropylene.
Kaw Kev xav ntawm ib tug Mundane -Sounding Specification
Qhov ntom ntom zoo li zoo li cov cuab yeej yooj yim. Nws tsuas yog loj muab faib los ntawm ntim. Thawj - xyoo physics.
Tab sis tus lej no txuas rau ze li txhua yam uas ua rau polycarbonate pab tau. Impact resistance kab mus rau molecular packing. Qhov hnyav txuag taug qab rau qhov ntom ntom zoo dua iav. Kev coj tus cwj pwm ua raws li qhov ceev npaum li cas hloov nrog qhov kub thiab txias. Kev tswj kom zoo ib yam rau kev ntsuas qhov ntom ntom raws li kev kuaj pom muaj kab mob.
Cov engineers uas ua hauj lwm nrog polycarbonate txhua hnub feem ntau tsis xav txog qhov ceev ceev. Nws dhau los ua kev paub keeb kwm yav dhau los, xav tias tsis yog xav txog. Tej zaum qhov ntawd yog qhov tsim nyog rau cov kws tshaj lij. Tab sis rau leej twg sim nkag siab tias yog vim li cas polycarbonate tshwm nyob rau hauv lub qhov rais bulletproof, aircraft canopies, thiab riot shields -thiab tsis yog nyob rau hauv cov khoom pheej yig daim ntawv thov- ntom yog qhov chaw pib piav qhia.
Tsis xaus. Pib.