Foaming yas ntawv hla ntu ua npuas tawg lossis los ntawm cov npuas ntawm ob yam:
Ⅰ. lub yaj nws tus kheej lub zog hauv zos yog tsawg dhau, tawg npuas yog tsim los ntawm sab nraud mus rau sab hauv.
Ⅱ. lub siab nyob ib ncig ntawm lub yaj yog me me, lub zos expansion ntawm lub npuas qhov tshwm sim, lub zog yog tsis muaj zog, lub npuas yog tsim los ntawm sab hauv tawm.
Hauv kev xyaum ntau lawm, tsis muaj qhov sib txawv ntawm ob lub luag haujlwm, yuav muaj nyob rau tib lub sijhawm, feem ntau ntawm cov qhov tawg yog qhov tsis sib xws ntawm cov vesicles hauv zos, lub zog yaj yog txo vim. Lub yaj nws tus kheej yog lub zog tsawg dhau thiab lub siab nyob ib puag ncig lub yaj yog me me ntau yam, hauv cov ntsiab lus, muaj ntau yam.
Ua ntej, qhov hnyav molecular lossis polymerization tsawg dhau. pvc resin tuaj yeem muab faib ua peb hom raws li nws txoj kev polymerization, uas yog, txoj kev emulsion pvc thiab ncua kev kawm pvc thiab lub cev pvc. Kev tsim cov khoom siv PVC ua npuas ncauj nruj, xws li emulsion txoj kev ntawm PVC resin tuaj yeem tau txais npuas sib xws, cov khoom siv du, tab sis qhov ruaj khov ntawm cov khoom yog qhov nyuaj rau kev tswj; thiab emulsion txoj kev ntawm PVC cob cov nqi ntau dua; Yog hais tias txoj kev ncua kev kawm ntawv ntawm PVC resin, cov tsos ntawm qhov zoo ntawm cov khoom thiab cov uniformity ntawm lub npuas yog me ntsis zuj zus.
Cov txheej txheem dav dav, tus nqi thiab kev ua haujlwm, thiab lwm yam, nws yog qhov tsim nyog los sib tov ob ntawm ib qho piv txwv, qhov piv yuav yog 80/20-20/80. Phaj tsim ib qhov dav dav hla ntu ntu, los ntawm lub taub hau extruder mus rau hauv lub qhov ncauj ntawm cov pwm kom muab faib mus rau qhov dav sib npaug li 1.3 m. Txhawm rau kom tau txais cov khoom siv roj hmab tsawg, cov khoom siv hluav taws xob siv yuav tsum tsis txhob muaj kev cuam tshuam ntau dhau los, hauv kev sib koom tes tag nrho ntawm cov kev xav tau ntawm cov kev xav tau ntawm lub suab nrov. Yog hais tias PVC resin viscosity siab dhau lawm, lub melt fluidity tsis zoo, nws yog ib qho nyuaj los xyuas kom meej lub flatness ntawm lub phaj, lub npuas qhov yuav tsis yooj yim rau nthuav, uas ua rau ib tug tsawg foaming lub sij hawm; ntawm qhov tsis sib xws, yog tias PVC resin viscosity tsawg dhau, nws yuav ua rau lub zog yaj yog qhov tsawg, yooj yim los ua npuas.
Kev tsim cov ntawv ua npuas ncauj yas yuav tsum siv SC-7 resin, sim tsis txhob siv SC-8 cob, lossis siv SC-8 resin tov nrog SC-5 lossis SC{{ 4}} cov.
Ⅲ. Tsis zoo thermal stability ntawm cov yaj, qhov chaw tsis raug lossis tswj qhov kub ntawm extrusion.
Zoo plasticization ntawm cov yaj yog ib qho yuav tsum tau ua ua ntej rau cov khoom siv yas foamed. Yog hais tias muaj teeb meem nrog lub tshav kub stabilizer, lub extrusion kub yog siab dhau, lub yaj yog nquag mus rau lub zos degradation thiab yuav torn vim qhov txo ntawm yaj lub zog, lub npuas yog loj heev; extrusion kub yog tsawg heev, yaj tsis yog plasticised, lub zog yog tsawg heev, tib yam yuav tawg npuas. Foaming yas daim ntawv ntau lawm, yuav tsum tsis tu ncua nyob rau hauv lub stabilizer 180 ~ 200 degrees ntawm stability test, tsis ua raws li cov stability ntawm raw cov ntaub ntawv yuav tsum tsis txhob siv los yog kho cov koob tshuaj, tom qab dhau qhov kev xeem thiab ces siv.
Ntxiv nrog rau xyuas kom meej tias cov yaj tsis degrade nyob rau hauv cov txheej txheem extrusion, lub stabilizer tseem muaj lub luag haujlwm tseem ceeb, uas yog, tswj qhov kub ntawm qhov decomposition ntawm tus neeg sawv cev tshuab. Yog hais tias tus nqi ntawm stabilizer ntau dhau los yog tsawg dhau, qhov decomposition kub ntawm tus neeg sawv cev tshuab yog tsawg dhau los yog siab dhau, uas tsis tsim nyog rau foaming. Stabilizer yuav tsum tau kho raws li qib ntawm resin siv, xws li kev siv ntawm 8- hom resin, plasticising kub yog tsawg, lub stabilizer yuav tsum tau nce kom tsim nyog, kom cov khoom plasticising kub thiab decomposition kub ntawm lub tshuab tshuab kom phim. Txawm li cas los xij, yog tias cov stabilizer ntxiv ntau dhau los yog qhov kub ntawm qhov kub siab dhau lawm, nws yuav ua rau kom ntxov decomposition ntawm tus neeg sawv cev ntawm lub tshuab extruder, uas ua rau cov roj foaming khiav tawm ntawm lub qhov them nyiaj thiab lub tshuab nqus tsev, yog tias ntxiv stabilizer. tsawg dhau los yog qhov kev khiav hauj lwm kub tsawg dhau, nws yuav ua rau cov foaming tsis tiav.
Kev ua haujlwm extrusion, ntxiv rau kom ntseeg tau tias cov yaj zoo plasticisation, cov yaj kub hauv lub extruder yuav tsum qis dua qhov kub ntawm cov tshuab tshuab, kom tsis txhob muaj kev puas tsuaj ntxov ntawm tus neeg sawv cev tshuab hauv lub tshuab; lub melting kub ntawm qhov tawm pwm yuav tsum mus txog qhov decomposition kub ntawm lub tshuab nqus tsev neeg sawv cev cheeb tsam, nyob rau hauv thiaj li yuav pab tau rau tag nrho cov foaming. Qhov chaw thiab tswj ntawm extrusion kub yuav tsum tau kho nyob rau hauv lub sij hawm raws li lub tshuab nqus tsev cov ntaub ntawv thiab cov yaj molding daim ntawv thaum lub tshuab yog switched. Xyuas kom meej tias cov khoom siv los ntawm lub qhov cua yog cov txiv kab ntxwv tev lub xeev, hauv qab ntawm cov ntsia hlau yuav tsum tsis txhob ua hmoov av; yaj extrusion los ntawm lub qhov ncauj ntawm cov pwm nto yuav tsum du, nrog ib tug tej yam kev mob ntawm elasticity, yuav tsum tsis txhob yog ib tug tawm pwm nyob rau hauv lub sagging los yog cross-section ntawm crystalline ntxhib.
Ⅳ. tsis tsim nyog ntxiv ntawm foaming agent.
Foaming yas ntawv ntau lawm feem ntau siv cov cua sov hom, cua sov-absorbing hom los yog tshav kub-absorbing, exothermic composite tshuav ntawm peb txawv tshuab. Ammonium azodicarboxylate, tseem hu ua AC, belongs rau azodyne activator, AC foaming tus neeg sawv cev decomposition kub yog siab, mus txog 232 degree, deb tshaj PVC ua kub, kev siv decomposition kub yuav tsum tau txo.
Exothermic foaming agent foaming tus nqi yog siab, txog 190-260ml / g, decomposition ceev, exothermic zoo, tab sis lub sij hawm foaming luv luv, suddenness kuj muaj zog. Yog li ntawd, thaum AC tshuab tus neeg saib xyuas ntau npaum li cas, cov roj tsim ntau dhau lawm, nws yuav ua rau lub siab hauv cov npuas loj hlob sai, qhov loj ntawm lub qhov npuas loj loj heev, cov pa roj tawm tawm sai heev, yog li ntawd, qhov loj ntawm lub qhov npuas npuas loj heev, cov pa roj tawm tawm sai heev, yog li ntawd, qhov loj ntawm lub qhov npuas npuas loj heev, cov pa roj tso tawm sai heev. cov qauv ntawm lub qhov npuas yog puas, qhov loj ntawm lub qhov npuas tsis sib npaug, thiab txawm tias qhov tsim ntawm lub qhov qhib qhov qauv, uas yuav tsim cov npuas loj thiab cov kab noj hniav hauv cheeb tsam.
Kev tsim cov khoom siv yas foamed, exothermic blowing agent AC yuav tsum tsis txhob siv ib leeg, yuav tsum tau siv nrog rau cov cua sov-absorbing tus neeg saib xyuas los yog siv cov cua sov thiab exothermic tshuav nyiaj li cas ntawm composite tshuaj tshuab tshuab. Inorganic foaming tus neeg saib xyuas - sodium bicarbonate (NaHCO3) yog cov cua sov-absorbing tus neeg sawv cev, txawm tias tus nqi foaming tsawg, tab sis lub sij hawm foaming yog ntev, thiab AC-hom foaming agent sib xyaw, tuaj yeem ua lub luag haujlwm sib luag thiab sib npaug. Exothermic foaming tus neeg saib xyuas los txhim kho cov cua sov-absorbing foaming tus neeg sawv cev ntawm cov roj tsim muaj peev xwm, cov cua sov-absorbing foaming tus neeg saib xyuas thiab cov qub cua txias, stabilizing nws decomposition thiab balanced tso pa roj, inhibit overheating degradation ntawm sab hauv ntawm lub phaj tuab kom txo tau cov nag lossis daus. ntawm residues, muaj cov nyhuv whitening.
Nyob rau hauv qhov kev pom zoo tsis cuam tshuam rau tus nqi foaming, nws yog qhov tsim nyog los ntxiv cov cua sov-absorbing tus neeg sawv cev los hloov qee cov exothermic blowing agent, txhawm rau tiv thaiv qhov sib ntxiv ntawm exothermic blowing agent tshwm sim los ntawm kev tawg ntawm cov npuas.1232 los yog BLA-616 tshuab tshuab yog ib qho exothermic thiab kub-absorbing sib npaug tshuab tshuab, decomposition ntawm lub sij hawm uas tsis yog inductive, tus nqi ntawm decomposition yog ceev, 10 feeb los yog li kom ncav cuag tus nqi siab tshaj ntawm cov roj, qeeb deflation, tsis muaj tawg ntawm cov pa roj, qhov siab tshaj plaws ntawm cov roj mus txog 156mL. Nws decomposition kub ntawm PVC ua kub ntau yam, yuav siv tau rau qhov loj ntawm thicker, complex zoo ntawm cov khoom dynamic molding txheej txheem, thiaj li yuav tshem tawm cov npuas tawg, kom lub stability ntawm foaming kev ua tau zoo.
Ⅴ. tsis zoo los yog tsis txaus noj cov txheej txheem txias.
Cov khoom nyob rau hauv cov txheej txheem foaming, lub decomposition ntawm lub tshuab cua tus neeg sawv cev nyob rau hauv lub yaj los ua npuas. Cov npuas no muaj nyob rau hauv lub ntim me me ntawm lub qhov npuas mus rau qhov loj ntim ntawm qhov npuas qhov nthuav dav. Qhov loj thiab tus naj npawb ntawm npuas tsis yog tsuas yog cuam tshuam nrog tus nqi ntawm cov tshuab tshuab ntxiv, tab sis kuj muaj feem xyuam rau lub zog ntawm cov polymer yaj. Lub zog muaj zog tsawg dhau, cov roj diffusion mus rau qhov chaw yaj yog yooj yim rau kev khiav tawm, cov npuas me me sib koom ua ke los tsim cov npuas loj. Qhov ntev molecular saw ntawm lub foaming regulator yog entangled thiab adheres rau cov molecular saw ntawm PVC, tsim ib tug tej yam network qauv. Ntawm qhov tod tes, nws txhawb cov plasticization ntawm cov khoom, ntawm qhov tod tes, nws txhim kho lub zog ntawm PVC yaj, kom cov phab ntsa ntawm cov npuas npuas tuaj yeem tiv taus lub siab ntawm cov roj hauv cov npuas hauv cov txheej txheem foaming, thiab yuav tsis tawg vim tsis muaj zog. Foaming regulator tuaj yeem ua rau cov khoom npuas qhov me me thiab ntau dua, cov qauv ntawm lub qhov npuas yog ntau dua, tsim nyog, txo qhov ntom ntawm lub cev foaming. Tsis zoo los yog tsis txaus npaum li cas ntawm foaming regulator yuav ua rau tsis muaj zog ntawm foaming lub cev, tawg npuas los yog hlua npuas.
Nws yuav tsum tau taw qhia tias qhov hnyav molecular thiab viscosity ntawm foam regulator tsim los ntawm cov tuam txhab sib txawv txawv heev, thaum cov khoom ua npuas ncauj tau tawg npuas lossis cascade npuas, thiab lwm txoj kev kho mob tsis zoo, kev hloov pauv ntawm cov khoom ua npuas ncauj lossis cov npuas dej. qhov tsim nyog nce ntau npaum li cas, feem ntau yuav tsim cov txiaj ntsig tseem ceeb. Txawm li cas los xij, kev nce lossis hloov cov foaming regulator nrog qhov hnyav dua molecular yuav ua rau kom qhov ntom ntawm cov khoom vim tias cov viscosity loj dhau, uas ua rau cov cua npuas hauv cov yaj tsis tuaj yeem nthuav dav. Thiab vim tias cov viscosity ntawm cov yaj yog loj heev, lub fluidity yuav tsis zoo, ua rau lub qhov ncauj ntawm cov pwm tawm ntawm cov khoom tsis sib xws, cuam tshuam lub flatness ntawm lub rooj tsavxwm, thiab txawm lub sij hawm ntau lawm tsis ntev, lub qhov ncauj fuzzy. cov khoom tsis ua hauj lwm tshwm sim, tshwj xeeb tshaj yog thaum cov khoom ntawm 10 hli tuab los yog tsawg tshaj li lub phaj yog feem ntau tshwm sim.
Kev tsim cov thicknesses sib txawv ntawm cov phaj, cov txheej txheem tswj cov koob tshuaj yuav tsum sib txawv nyob ntawm qhov xwm txheej, tib lub mis, nyias phaj tsis muaj npuas qhov, tuab phaj npuas qhov, nws tsim nyog ntxiv 0.{{1 } }.5 qhov chaw ntawm cov txheej txheem kev tswj hwm, tsuas yog tshem tawm cov npuas ua lub hauv paus rau micro-additive, tsis txhob recklessly, blindly ntxiv ntxiv, thiaj li tsis ua rau kom qhov ntom ntawm cov khoom, cuam tshuam rau lub sijhawm ua haujlwm zoo.
Ⅵ. calcium carbonate ntau dhau, qhov loj me me, ua haujlwm tsis zoo.
CaCO3 ntxiv ntau dhau, txawm hais tias nws tuaj yeem tsim muaj npuas ntau, tab sis yog tias calcium carbonate ntxiv ntau dhau los yog loj heev, cov haujlwm tsis zoo, tsim cov agglomerates, dispersed nyob rau hauv cov resin los yog resin cross-section nrog ib tug phem. kev sib xyaw ua ke, ua rau txo qis hauv lub zog ntawm cov yaj, cov yaj yog ib qho yooj yim los tsim npuas expansion npuas.
Foamed yas ntawv ntau lawm yuav tsum nruj me ntsis tswj cov calcium carbonate koob, particle loj thiab kev ua. Thaum cov calcium carbonate ntau dhau lawm, lub tshuab ua npuas dej yuav tsum tau nce ntxiv.
Ⅶ. kev siv cov pwm tsis raug.
Crust ua npuas ncauj yas ntawv ntau lawm, raws li lub thickness ntawm cov khoom yog txawv, configuration ntawm lub qhov ncauj ntawm pwm ncaj seem ntev thiab compression piv kuj txawv. Cov phaj tuab lub qhov ncauj pwm vim cov npuas npuas yog thicker, muaj qhov elastic deformation qhov chaw, qhov dav dav tsim ntawm lub qhov ncauj ntawm cov pwm ncaj seem yog ntev dua, compression piv yog loj, thiaj li yuav txhim kho cov yaj siab thiab foaming multiplier; nyias phaj lub qhov ncauj pwm vim tias cov npuas dej yog nyias, qhov chaw elastic yog me me, rigidity loj dua, cov qauv tsim ntawm lub qhov ncauj ntawm cov pwm ncaj yog luv dua, compression ratio me dua, txhawm rau tiv thaiv kom tsis txhob muaj ntau dhau ntawm cov pwm vim yog yaj. Yog tias tsis siv kom zoo, kev tsim cov phaj nyias, kev siv tsis zoo ntawm cov phaj tuab lub qhov ncauj pwm, vim qhov tawm ntawm cov pwm cov khoom ntws tawm tuaj yeem nce, cov khoom siv tsis sib xws, ua rau qhov tsis sib xws, yaj lub zog yog txo, thiab txawm tias lub phaj raug rub tawm. , lub voj voog ntau lawm yog luv; kev tsim cov phaj tuab, kev siv tsis zoo ntawm nyias phaj lub qhov ncauj pwm, yuav yog vim qhov tawm ntawm cov pwm melting siab yog me me, kom cov npuas qhov nce thiab ua rau tawg ntawm cov npuas. Txawv thickness ntawm crust foam yas ntawv ntau lawm, yuav tsum yog qhov kev xaiv ntawm lub qhov ncauj pwm.
Ⅷ. phaj cross-section foaming lossis cov khoom tsis sib xws, hauv zos tsis muaj cov khoom siv.
Sheet cross-section ua npuas ncauj los yog cov khoom tsis sib xws, hauv zos tsis muaj cov khoom siv cuam tshuam ntau yam, thoob plaws hauv kev sib xyaw thiab extrusion ntawm tag nrho cov txheej txheem. Piv txwv li, cov khoom siv mis tsis tsim nyog, cov ntaub ntawv sab nrauv yog me me, qhov kub ntawm qhov extruder 5 yog ib qho yooj yim rau overheat, uas ua rau kub kub ntawm cov tub ntxhais sib xyaw ua ke, nruab nrab ntawm cov phaj tau pom cov npuas loj, cov hlua ua npuas, yellowing, phaj nto roughness thiab lwm yam tsis xws luag; ib lub lauj kaub sib tov ntau dhau lawm, qhov sib tov kub tsawg dhau, sib tov lub sij hawm luv luv, lub hauv pliaj yog ntxiv me ntsis, yooj yim rau kev sib xyaw ntawm cov khoom sib cais tsis sib xws.
Kev txav mus los tsis zoo thiab extrusion txheej txheem ntawm lub qhov ncauj pwm kub los yog ntsia liaj qhov rooj tsis raug kho, yuav ua rau yaj extrusion los ntawm lub qhov ncauj pwm, cov khoom tsis sib xws, tsis muaj cov khoom siv hauv zos, tshwm sim los ntawm cov npuas dej los ntawm cov kev sib txuas tsis muaj zog hauv lub qhov ncauj. expansion thiab tawg npuas. Yog li ntawd, nyob rau hauv kev sib tov thiab extrusion ntau lawm txheej txheem, peb yuav tsum ua raws li cov qauv thiab cov txheej txheem kev khiav hauj lwm cov txheej txheem, thiab cov coj tsom xam ntawm tawg npuas, feem, siv ntau txoj kev los daws. Yog tias cov npuas tawg tau raug kho nyob rau hauv tib txoj hauj lwm, nws txhais tau hais tias lub siab yaj nyob rau hauv qhov no yog tsawg heev, thiab nws yuav daws tau los ntawm kev siv cov kev hloov kho ntawm lub qhov ncauj pwm bolt los yog kub. Ntxiv nrog rau cov kev ntsuas saum toj no, kev kho qhov sib txawv ntawm txhua ntu ntawm cov qauv shaping kuj muaj qee yam cuam tshuam rau kev tshem tawm cov npuas qhov. Yog hais tias qhov sib txawv ntawm thawj shaping phaj thiab thib ob shaping phaj yog loj heev, lub yaj yuav tsum nruj nreem nruj nreem nyob rau hauv lub siab ntawm lub shaping template vim tsis txaus cua txias, uas ua rau ib tug nce nyob rau hauv ntom thiab yuav ua rau tawg npuas;
Yog tias tus qauv thib peb thiab qhov sib txawv ntawm qhov thib plaub yog qhov sib txawv loj heev, tom qab txaus txias txias, cov qauv tsis muaj chaw rau compression deformation, uas ua rau plaub tus qauv yog qhov nyuaj rau muab tso rau hauv qhov chaw, phaj thickness nce. Qhov tsim nyog nce nyob rau hauv qhov sib txawv ntawm qhov thib ob thiab thib peb template sib txawv, ntawm ib sab, tuaj yeem tiv thaiv cov npuas yaj ua ntej qhov txias tshwm sim ua ntej npuas, ntawm qhov tod tes, tus qauv thib peb ntawm qhov kub thiab txias, tab sis kuj tuaj yeem nias rau hauv. qhov chaw los tiv thaiv qhov nce ntawm phaj thickness.
Thib ob, thaum tsim cov phaj tuab, txo cov ntsia hlau kub, lub qhov ncauj pwm roj kub, thawj qhov thaiv shaping ntaus ntawv txias dej kub, thiab lwm yam., kuj muaj cov txiaj ntsig zoo ntawm kev tshem tawm cov npuas tawg.
